/* Common target dependent code for GDB on ARM systems.
Copyright (C) 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1998, 1999, 2000,
- 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
Free Software Foundation, Inc.
This file is part of GDB.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
-#include <ctype.h> /* XXX for isupper () */
+#include <ctype.h> /* XXX for isupper (). */
#include "defs.h"
#include "frame.h"
#include "gdbcmd.h"
#include "gdbcore.h"
#include "gdb_string.h"
-#include "dis-asm.h" /* For register styles. */
+#include "dis-asm.h" /* For register styles. */
#include "regcache.h"
+#include "reggroups.h"
#include "doublest.h"
#include "value.h"
#include "arch-utils.h"
#include "prologue-value.h"
#include "target-descriptions.h"
#include "user-regs.h"
+#include "observer.h"
#include "arm-tdep.h"
#include "gdb/sim-arm.h"
#include "gdb_assert.h"
#include "vec.h"
+#include "features/arm-with-m.c"
+#include "features/arm-with-iwmmxt.c"
+#include "features/arm-with-vfpv2.c"
+#include "features/arm-with-vfpv3.c"
+#include "features/arm-with-neon.c"
+
static int arm_debug;
/* Macros for setting and testing a bit in a minimal symbol that marks
MSYMBOL_SET_SPECIAL Actually sets the "special" bit.
MSYMBOL_IS_SPECIAL Tests the "special" bit in a minimal symbol. */
-#define MSYMBOL_SET_SPECIAL(msym) \
+#define MSYMBOL_SET_SPECIAL(msym) \
MSYMBOL_TARGET_FLAG_1 (msym) = 1
#define MSYMBOL_IS_SPECIAL(msym) \
{
"auto",
"arm",
- "thumb"
+ "thumb",
+ NULL
};
static const char *arm_fallback_mode_string = "auto";
static const char *arm_force_mode_string = "auto";
+/* Internal override of the execution mode. -1 means no override,
+ 0 means override to ARM mode, 1 means override to Thumb mode.
+ The effect is the same as if arm_force_mode has been set by the
+ user (except the internal override has precedence over a user's
+ arm_force_mode override). */
+static int arm_override_mode = -1;
+
/* Number of different reg name sets (options). */
static int num_disassembly_options;
-/* The standard register names, and all the valid aliases for them. */
+/* The standard register names, and all the valid aliases for them. Note
+ that `fp', `sp' and `pc' are not added in this alias list, because they
+ have been added as builtin user registers in
+ std-regs.c:_initialize_frame_reg. */
static const struct
{
const char *name;
{ "tr", 9 },
/* Special names. */
{ "ip", 12 },
- { "sp", 13 },
{ "lr", 14 },
- { "pc", 15 },
/* Names used by GCC (not listed in the ARM EABI). */
{ "sl", 10 },
- { "fp", 11 },
/* A special name from the older ATPCS. */
{ "wr", 7 },
};
static void convert_to_extended (const struct floatformat *, void *,
const void *, int);
-static void arm_neon_quad_read (struct gdbarch *gdbarch,
- struct regcache *regcache,
- int regnum, gdb_byte *buf);
+static enum register_status arm_neon_quad_read (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int regnum, gdb_byte *buf);
static void arm_neon_quad_write (struct gdbarch *gdbarch,
struct regcache *regcache,
int regnum, const gdb_byte *buf);
+static int thumb_insn_size (unsigned short inst1);
+
struct arm_prologue_cache
{
/* The stack pointer at the time this frame was created; i.e. the
int arm_apcs_32 = 1;
+/* Return the bit mask in ARM_PS_REGNUM that indicates Thumb mode. */
+
+int
+arm_psr_thumb_bit (struct gdbarch *gdbarch)
+{
+ if (gdbarch_tdep (gdbarch)->is_m)
+ return XPSR_T;
+ else
+ return CPSR_T;
+}
+
/* Determine if FRAME is executing in Thumb mode. */
-static int
+int
arm_frame_is_thumb (struct frame_info *frame)
{
CORE_ADDR cpsr;
+ ULONGEST t_bit = arm_psr_thumb_bit (get_frame_arch (frame));
/* Every ARM frame unwinder can unwind the T bit of the CPSR, either
directly (from a signal frame or dummy frame) or by interpreting
trust the unwinders. */
cpsr = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
- return (cpsr & CPSR_T) != 0;
+ return (cpsr & t_bit) != 0;
}
/* Callback for VEC_lower_bound. */
return 0;
}
-static CORE_ADDR arm_get_next_pc_raw (struct frame_info *frame,
- CORE_ADDR pc, int insert_bkpt);
-
/* Determine if the program counter specified in MEMADDR is in a Thumb
function. This function should be called for addresses unrelated to
any executing frame; otherwise, prefer arm_frame_is_thumb. */
-static int
-arm_pc_is_thumb (CORE_ADDR memaddr)
+int
+arm_pc_is_thumb (struct gdbarch *gdbarch, CORE_ADDR memaddr)
{
struct obj_section *sec;
struct minimal_symbol *sym;
char type;
+ struct displaced_step_closure* dsc
+ = get_displaced_step_closure_by_addr(memaddr);
+
+ /* If checking the mode of displaced instruction in copy area, the mode
+ should be determined by instruction on the original address. */
+ if (dsc)
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: check mode of %.8lx instead of %.8lx\n",
+ (unsigned long) dsc->insn_addr,
+ (unsigned long) memaddr);
+ memaddr = dsc->insn_addr;
+ }
/* If bit 0 of the address is set, assume this is a Thumb address. */
if (IS_THUMB_ADDR (memaddr))
return 1;
+ /* Respect internal mode override if active. */
+ if (arm_override_mode != -1)
+ return arm_override_mode;
+
/* If the user wants to override the symbol table, let him. */
if (strcmp (arm_force_mode_string, "arm") == 0)
return 0;
if (strcmp (arm_force_mode_string, "thumb") == 0)
return 1;
+ /* ARM v6-M and v7-M are always in Thumb mode. */
+ if (gdbarch_tdep (gdbarch)->is_m)
+ return 1;
+
/* If there are mapping symbols, consult them. */
type = arm_find_mapping_symbol (memaddr, NULL);
if (type)
target, then trust the current value of $cpsr. This lets
"display/i $pc" always show the correct mode (though if there is
a symbol table we will not reach here, so it still may not be
- displayed in the mode it will be executed).
-
- As a further heuristic if we detect that we are doing a single-step we
- see what state executing the current instruction ends up with us being
- in. */
+ displayed in the mode it will be executed). */
if (target_has_registers)
- {
- struct frame_info *current_frame = get_current_frame ();
- CORE_ADDR current_pc = get_frame_pc (current_frame);
- int is_thumb = arm_frame_is_thumb (current_frame);
- CORE_ADDR next_pc;
- if (memaddr == current_pc)
- return is_thumb;
- else
- {
- struct gdbarch *gdbarch = get_frame_arch (current_frame);
- next_pc = arm_get_next_pc_raw (current_frame, current_pc, FALSE);
- if (memaddr == gdbarch_addr_bits_remove (gdbarch, next_pc))
- return IS_THUMB_ADDR (next_pc);
- else
- return is_thumb;
- }
- }
+ return arm_frame_is_thumb (get_current_frame ());
/* Otherwise we're out of luck; we assume ARM. */
return 0;
}
/* Return 1 if PC is the start of a compiler helper function which
- can be safely ignored during prologue skipping. */
+ can be safely ignored during prologue skipping. IS_THUMB is true
+ if the function is known to be a Thumb function due to the way it
+ is being called. */
static int
-skip_prologue_function (CORE_ADDR pc)
+skip_prologue_function (struct gdbarch *gdbarch, CORE_ADDR pc, int is_thumb)
{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
struct minimal_symbol *msym;
- const char *name;
msym = lookup_minimal_symbol_by_pc (pc);
- if (msym == NULL || SYMBOL_VALUE_ADDRESS (msym) != pc)
- return 0;
+ if (msym != NULL
+ && SYMBOL_VALUE_ADDRESS (msym) == pc
+ && SYMBOL_LINKAGE_NAME (msym) != NULL)
+ {
+ const char *name = SYMBOL_LINKAGE_NAME (msym);
- name = SYMBOL_LINKAGE_NAME (msym);
- if (name == NULL)
- return 0;
+ /* The GNU linker's Thumb call stub to foo is named
+ __foo_from_thumb. */
+ if (strstr (name, "_from_thumb") != NULL)
+ name += 2;
- /* The GNU linker's Thumb call stub to foo is named
- __foo_from_thumb. */
- if (strstr (name, "_from_thumb") != NULL)
- name += 2;
+ /* On soft-float targets, __truncdfsf2 is called to convert promoted
+ arguments to their argument types in non-prototyped
+ functions. */
+ if (strncmp (name, "__truncdfsf2", strlen ("__truncdfsf2")) == 0)
+ return 1;
+ if (strncmp (name, "__aeabi_d2f", strlen ("__aeabi_d2f")) == 0)
+ return 1;
- /* On soft-float targets, __truncdfsf2 is called to convert promoted
- arguments to their argument types in non-prototyped
- functions. */
- if (strncmp (name, "__truncdfsf2", strlen ("__truncdfsf2")) == 0)
- return 1;
- if (strncmp (name, "__aeabi_d2f", strlen ("__aeabi_d2f")) == 0)
- return 1;
+ /* Internal functions related to thread-local storage. */
+ if (strncmp (name, "__tls_get_addr", strlen ("__tls_get_addr")) == 0)
+ return 1;
+ if (strncmp (name, "__aeabi_read_tp", strlen ("__aeabi_read_tp")) == 0)
+ return 1;
+ }
+ else
+ {
+ /* If we run against a stripped glibc, we may be unable to identify
+ special functions by name. Check for one important case,
+ __aeabi_read_tp, by comparing the *code* against the default
+ implementation (this is hand-written ARM assembler in glibc). */
+
+ if (!is_thumb
+ && read_memory_unsigned_integer (pc, 4, byte_order_for_code)
+ == 0xe3e00a0f /* mov r0, #0xffff0fff */
+ && read_memory_unsigned_integer (pc + 4, 4, byte_order_for_code)
+ == 0xe240f01f) /* sub pc, r0, #31 */
+ return 1;
+ }
return 0;
}
#define BranchDest(addr,instr) \
((CORE_ADDR) (((long) (addr)) + 8 + (sbits (instr, 0, 23) << 2)))
+/* Extract the immediate from instruction movw/movt of encoding T. INSN1 is
+ the first 16-bit of instruction, and INSN2 is the second 16-bit of
+ instruction. */
+#define EXTRACT_MOVW_MOVT_IMM_T(insn1, insn2) \
+ ((bits ((insn1), 0, 3) << 12) \
+ | (bits ((insn1), 10, 10) << 11) \
+ | (bits ((insn2), 12, 14) << 8) \
+ | bits ((insn2), 0, 7))
+
+/* Extract the immediate from instruction movw/movt of encoding A. INSN is
+ the 32-bit instruction. */
+#define EXTRACT_MOVW_MOVT_IMM_A(insn) \
+ ((bits ((insn), 16, 19) << 12) \
+ | bits ((insn), 0, 11))
+
+/* Decode immediate value; implements ThumbExpandImmediate pseudo-op. */
+
+static unsigned int
+thumb_expand_immediate (unsigned int imm)
+{
+ unsigned int count = imm >> 7;
+
+ if (count < 8)
+ switch (count / 2)
+ {
+ case 0:
+ return imm & 0xff;
+ case 1:
+ return (imm & 0xff) | ((imm & 0xff) << 16);
+ case 2:
+ return ((imm & 0xff) << 8) | ((imm & 0xff) << 24);
+ case 3:
+ return (imm & 0xff) | ((imm & 0xff) << 8)
+ | ((imm & 0xff) << 16) | ((imm & 0xff) << 24);
+ }
+
+ return (0x80 | (imm & 0x7f)) << (32 - count);
+}
+
+/* Return 1 if the 16-bit Thumb instruction INST might change
+ control flow, 0 otherwise. */
+
+static int
+thumb_instruction_changes_pc (unsigned short inst)
+{
+ if ((inst & 0xff00) == 0xbd00) /* pop {rlist, pc} */
+ return 1;
+
+ if ((inst & 0xf000) == 0xd000) /* conditional branch */
+ return 1;
+
+ if ((inst & 0xf800) == 0xe000) /* unconditional branch */
+ return 1;
+
+ if ((inst & 0xff00) == 0x4700) /* bx REG, blx REG */
+ return 1;
+
+ if ((inst & 0xff87) == 0x4687) /* mov pc, REG */
+ return 1;
+
+ if ((inst & 0xf500) == 0xb100) /* CBNZ or CBZ. */
+ return 1;
+
+ return 0;
+}
+
+/* Return 1 if the 32-bit Thumb instruction in INST1 and INST2
+ might change control flow, 0 otherwise. */
+
+static int
+thumb2_instruction_changes_pc (unsigned short inst1, unsigned short inst2)
+{
+ if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000)
+ {
+ /* Branches and miscellaneous control instructions. */
+
+ if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000)
+ {
+ /* B, BL, BLX. */
+ return 1;
+ }
+ else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00)
+ {
+ /* SUBS PC, LR, #imm8. */
+ return 1;
+ }
+ else if ((inst2 & 0xd000) == 0x8000 && (inst1 & 0x0380) != 0x0380)
+ {
+ /* Conditional branch. */
+ return 1;
+ }
+
+ return 0;
+ }
+
+ if ((inst1 & 0xfe50) == 0xe810)
+ {
+ /* Load multiple or RFE. */
+
+ if (bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* LDMIA or POP */
+ if (bit (inst2, 15))
+ return 1;
+ }
+ else if (!bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* LDMDB */
+ if (bit (inst2, 15))
+ return 1;
+ }
+ else if (bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* RFEIA */
+ return 1;
+ }
+ else if (!bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* RFEDB */
+ return 1;
+ }
+
+ return 0;
+ }
+
+ if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00)
+ {
+ /* MOV PC or MOVS PC. */
+ return 1;
+ }
+
+ if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000)
+ {
+ /* LDR PC. */
+ if (bits (inst1, 0, 3) == 15)
+ return 1;
+ if (bit (inst1, 7))
+ return 1;
+ if (bit (inst2, 11))
+ return 1;
+ if ((inst2 & 0x0fc0) == 0x0000)
+ return 1;
+
+ return 0;
+ }
+
+ if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000)
+ {
+ /* TBB. */
+ return 1;
+ }
+
+ if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf010)
+ {
+ /* TBH. */
+ return 1;
+ }
+
+ return 0;
+}
+
/* Analyze a Thumb prologue, looking for a recognizable stack frame
and frame pointer. Scan until we encounter a store that could
clobber the stack frame unexpectedly, or an unknown instruction.
struct pv_area *stack;
struct cleanup *back_to;
CORE_ADDR offset;
+ CORE_ADDR unrecognized_pc = 0;
for (i = 0; i < 16; i++)
regs[i] = pv_register (i, 0);
constant = read_memory_unsigned_integer (loc, 4, byte_order);
regs[bits (insn, 8, 10)] = pv_constant (constant);
}
- else if ((insn & 0xe000) == 0xe000 && cache == NULL)
+ else if (thumb_insn_size (insn) == 4) /* 32-bit Thumb-2 instructions. */
{
- /* Only recognize 32-bit instructions for prologue skipping. */
unsigned short inst2;
inst2 = read_memory_unsigned_integer (start + 2, 2,
if (bit (inst2, 12) == 0)
nextpc = nextpc & 0xfffffffc;
- if (!skip_prologue_function (nextpc))
+ if (!skip_prologue_function (gdbarch, nextpc,
+ bit (inst2, 12) != 0))
+ break;
+ }
+
+ else if ((insn & 0xffd0) == 0xe900 /* stmdb Rn{!},
+ { registers } */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ {
+ pv_t addr = regs[bits (insn, 0, 3)];
+ int regno;
+
+ if (pv_area_store_would_trash (stack, addr))
+ break;
+
+ /* Calculate offsets of saved registers. */
+ for (regno = ARM_LR_REGNUM; regno >= 0; regno--)
+ if (inst2 & (1 << regno))
+ {
+ addr = pv_add_constant (addr, -4);
+ pv_area_store (stack, addr, 4, regs[regno]);
+ }
+
+ if (insn & 0x0020)
+ regs[bits (insn, 0, 3)] = addr;
+ }
+
+ else if ((insn & 0xff50) == 0xe940 /* strd Rt, Rt2,
+ [Rn, #+/-imm]{!} */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ {
+ int regno1 = bits (inst2, 12, 15);
+ int regno2 = bits (inst2, 8, 11);
+ pv_t addr = regs[bits (insn, 0, 3)];
+
+ offset = inst2 & 0xff;
+ if (insn & 0x0080)
+ addr = pv_add_constant (addr, offset);
+ else
+ addr = pv_add_constant (addr, -offset);
+
+ if (pv_area_store_would_trash (stack, addr))
+ break;
+
+ pv_area_store (stack, addr, 4, regs[regno1]);
+ pv_area_store (stack, pv_add_constant (addr, 4),
+ 4, regs[regno2]);
+
+ if (insn & 0x0020)
+ regs[bits (insn, 0, 3)] = addr;
+ }
+
+ else if ((insn & 0xfff0) == 0xf8c0 /* str Rt,[Rn,+/-#imm]{!} */
+ && (inst2 & 0x0c00) == 0x0c00
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ {
+ int regno = bits (inst2, 12, 15);
+ pv_t addr = regs[bits (insn, 0, 3)];
+
+ offset = inst2 & 0xff;
+ if (inst2 & 0x0200)
+ addr = pv_add_constant (addr, offset);
+ else
+ addr = pv_add_constant (addr, -offset);
+
+ if (pv_area_store_would_trash (stack, addr))
+ break;
+
+ pv_area_store (stack, addr, 4, regs[regno]);
+
+ if (inst2 & 0x0100)
+ regs[bits (insn, 0, 3)] = addr;
+ }
+
+ else if ((insn & 0xfff0) == 0xf8c0 /* str.w Rt,[Rn,#imm] */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ {
+ int regno = bits (inst2, 12, 15);
+ pv_t addr;
+
+ offset = inst2 & 0xfff;
+ addr = pv_add_constant (regs[bits (insn, 0, 3)], offset);
+
+ if (pv_area_store_would_trash (stack, addr))
break;
+
+ pv_area_store (stack, addr, 4, regs[regno]);
}
- else if ((insn & 0xfe50) == 0xe800 /* stm{db,ia} Rn[!], { registers } */
+
+ else if ((insn & 0xffd0) == 0xf880 /* str{bh}.w Rt,[Rn,#imm] */
&& pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Ignore stores of argument registers to the stack. */
;
- else if ((insn & 0xfe50) == 0xe840 /* strd Rt, Rt2, [Rn, #imm] */
+
+ else if ((insn & 0xffd0) == 0xf800 /* str{bh} Rt,[Rn,#+/-imm] */
+ && (inst2 & 0x0d00) == 0x0c00
&& pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Ignore stores of argument registers to the stack. */
;
- else if ((insn & 0xffd0) == 0xe890 /* ldmia Rn[!], { registers } */
- && (inst2 & 0x8000) == 0x0000
- && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+
+ else if ((insn & 0xffd0) == 0xe890 /* ldmia Rn[!],
+ { registers } */
+ && (inst2 & 0x8000) == 0x0000
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Ignore block loads from the stack, potentially copying
+ parameters from memory. */
;
- else if ((insn & 0xfbf0) == 0xf100 /* add.w Rd, Rn, #imm */
- && (inst2 & 0x8000) == 0x0000)
- /* Since we only recognize this for prologue skipping, do not bother
- to compute the constant. */
- regs[bits (inst2, 8, 11)] = regs[bits (insn, 0, 3)];
- else if ((insn & 0xfbf0) == 0xf1a0 /* sub.w Rd, Rn, #imm12 */
- && (inst2 & 0x8000) == 0x0000)
- /* Since we only recognize this for prologue skipping, do not bother
- to compute the constant. */
- regs[bits (inst2, 8, 11)] = regs[bits (insn, 0, 3)];
- else if ((insn & 0xfbf0) == 0xf2a0 /* sub.w Rd, Rn, #imm8 */
- && (inst2 & 0x8000) == 0x0000)
- /* Since we only recognize this for prologue skipping, do not bother
- to compute the constant. */
- regs[bits (inst2, 8, 11)] = regs[bits (insn, 0, 3)];
- else if ((insn & 0xff50) == 0xf850 /* ldr.w Rd, [Rn, #imm]{!} */
+
+ else if ((insn & 0xffb0) == 0xe950 /* ldrd Rt, Rt2,
+ [Rn, #+/-imm] */
&& pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Similarly ignore dual loads from the stack. */
;
- else if ((insn & 0xff50) == 0xe950 /* ldrd Rt, Rt2, [Rn, #imm]{!} */
+
+ else if ((insn & 0xfff0) == 0xf850 /* ldr Rt,[Rn,#+/-imm] */
+ && (inst2 & 0x0d00) == 0x0c00
&& pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Similarly ignore single loads from the stack. */
;
- else if ((insn & 0xff50) == 0xf800 /* strb.w or strh.w */
+
+ else if ((insn & 0xfff0) == 0xf8d0 /* ldr.w Rt,[Rn,#imm] */
&& pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Similarly ignore single loads from the stack. */
;
- else
+
+ else if ((insn & 0xfbf0) == 0xf100 /* add.w Rd, Rn, #imm */
+ && (inst2 & 0x8000) == 0x0000)
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_add_constant (regs[bits (insn, 0, 3)],
+ thumb_expand_immediate (imm));
+ }
+
+ else if ((insn & 0xfbf0) == 0xf200 /* addw Rd, Rn, #imm */
+ && (inst2 & 0x8000) == 0x0000)
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_add_constant (regs[bits (insn, 0, 3)], imm);
+ }
+
+ else if ((insn & 0xfbf0) == 0xf1a0 /* sub.w Rd, Rn, #imm */
+ && (inst2 & 0x8000) == 0x0000)
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_add_constant (regs[bits (insn, 0, 3)],
+ - (CORE_ADDR) thumb_expand_immediate (imm));
+ }
+
+ else if ((insn & 0xfbf0) == 0xf2a0 /* subw Rd, Rn, #imm */
+ && (inst2 & 0x8000) == 0x0000)
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_add_constant (regs[bits (insn, 0, 3)], - (CORE_ADDR) imm);
+ }
+
+ else if ((insn & 0xfbff) == 0xf04f) /* mov.w Rd, #const */
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_constant (thumb_expand_immediate (imm));
+ }
+
+ else if ((insn & 0xfbf0) == 0xf240) /* movw Rd, #const */
+ {
+ unsigned int imm
+ = EXTRACT_MOVW_MOVT_IMM_T (insn, inst2);
+
+ regs[bits (inst2, 8, 11)] = pv_constant (imm);
+ }
+
+ else if (insn == 0xea5f /* mov.w Rd,Rm */
+ && (inst2 & 0xf0f0) == 0)
+ {
+ int dst_reg = (inst2 & 0x0f00) >> 8;
+ int src_reg = inst2 & 0xf;
+ regs[dst_reg] = regs[src_reg];
+ }
+
+ else if ((insn & 0xff7f) == 0xf85f) /* ldr.w Rt,<label> */
+ {
+ /* Constant pool loads. */
+ unsigned int constant;
+ CORE_ADDR loc;
+
+ offset = bits (insn, 0, 11);
+ if (insn & 0x0080)
+ loc = start + 4 + offset;
+ else
+ loc = start + 4 - offset;
+
+ constant = read_memory_unsigned_integer (loc, 4, byte_order);
+ regs[bits (inst2, 12, 15)] = pv_constant (constant);
+ }
+
+ else if ((insn & 0xff7f) == 0xe95f) /* ldrd Rt,Rt2,<label> */
{
- /* We don't know what this instruction is. We're finished
- scanning. NOTE: Recognizing more safe-to-ignore
- instructions here will improve support for optimized
- code. */
+ /* Constant pool loads. */
+ unsigned int constant;
+ CORE_ADDR loc;
+
+ offset = bits (insn, 0, 7) << 2;
+ if (insn & 0x0080)
+ loc = start + 4 + offset;
+ else
+ loc = start + 4 - offset;
+
+ constant = read_memory_unsigned_integer (loc, 4, byte_order);
+ regs[bits (inst2, 12, 15)] = pv_constant (constant);
+
+ constant = read_memory_unsigned_integer (loc + 4, 4, byte_order);
+ regs[bits (inst2, 8, 11)] = pv_constant (constant);
+ }
+
+ else if (thumb2_instruction_changes_pc (insn, inst2))
+ {
+ /* Don't scan past anything that might change control flow. */
break;
}
+ else
+ {
+ /* The optimizer might shove anything into the prologue,
+ so we just skip what we don't recognize. */
+ unrecognized_pc = start;
+ }
start += 2;
}
- else
+ else if (thumb_instruction_changes_pc (insn))
{
- /* We don't know what this instruction is. We're finished
- scanning. NOTE: Recognizing more safe-to-ignore
- instructions here will improve support for optimized
- code. */
+ /* Don't scan past anything that might change control flow. */
break;
}
+ else
+ {
+ /* The optimizer might shove anything into the prologue,
+ so we just skip what we don't recognize. */
+ unrecognized_pc = start;
+ }
start += 2;
}
fprintf_unfiltered (gdb_stdlog, "Prologue scan stopped at %s\n",
paddress (gdbarch, start));
+ if (unrecognized_pc == 0)
+ unrecognized_pc = start;
+
if (cache == NULL)
{
do_cleanups (back_to);
- return start;
+ return unrecognized_pc;
}
if (pv_is_register (regs[ARM_FP_REGNUM], ARM_SP_REGNUM))
cache->saved_regs[i].addr = offset;
do_cleanups (back_to);
- return start;
+ return unrecognized_pc;
}
-/* Advance the PC across any function entry prologue instructions to
- reach some "real" code.
-
- The APCS (ARM Procedure Call Standard) defines the following
- prologue:
- mov ip, sp
- [stmfd sp!, {a1,a2,a3,a4}]
- stmfd sp!, {...,fp,ip,lr,pc}
- [stfe f7, [sp, #-12]!]
- [stfe f6, [sp, #-12]!]
- [stfe f5, [sp, #-12]!]
- [stfe f4, [sp, #-12]!]
- sub fp, ip, #nn @@ nn == 20 or 4 depending on second insn */
+/* Try to analyze the instructions starting from PC, which load symbol
+ __stack_chk_guard. Return the address of instruction after loading this
+ symbol, set the dest register number to *BASEREG, and set the size of
+ instructions for loading symbol in OFFSET. Return 0 if instructions are
+ not recognized. */
static CORE_ADDR
-arm_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
+arm_analyze_load_stack_chk_guard(CORE_ADDR pc, struct gdbarch *gdbarch,
+ unsigned int *destreg, int *offset)
{
enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
- unsigned long inst;
- CORE_ADDR skip_pc;
- CORE_ADDR func_addr, limit_pc;
- struct symtab_and_line sal;
+ int is_thumb = arm_pc_is_thumb (gdbarch, pc);
+ unsigned int low, high, address;
- /* See if we can determine the end of the prologue via the symbol table.
- If so, then return either PC, or the PC after the prologue, whichever
- is greater. */
- if (find_pc_partial_function (pc, NULL, &func_addr, NULL))
+ address = 0;
+ if (is_thumb)
+ {
+ unsigned short insn1
+ = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
+
+ if ((insn1 & 0xf800) == 0x4800) /* ldr Rd, #immed */
+ {
+ *destreg = bits (insn1, 8, 10);
+ *offset = 2;
+ address = bits (insn1, 0, 7);
+ }
+ else if ((insn1 & 0xfbf0) == 0xf240) /* movw Rd, #const */
+ {
+ unsigned short insn2
+ = read_memory_unsigned_integer (pc + 2, 2, byte_order_for_code);
+
+ low = EXTRACT_MOVW_MOVT_IMM_T (insn1, insn2);
+
+ insn1
+ = read_memory_unsigned_integer (pc + 4, 2, byte_order_for_code);
+ insn2
+ = read_memory_unsigned_integer (pc + 6, 2, byte_order_for_code);
+
+ /* movt Rd, #const */
+ if ((insn1 & 0xfbc0) == 0xf2c0)
+ {
+ high = EXTRACT_MOVW_MOVT_IMM_T (insn1, insn2);
+ *destreg = bits (insn2, 8, 11);
+ *offset = 8;
+ address = (high << 16 | low);
+ }
+ }
+ }
+ else
+ {
+ unsigned int insn
+ = read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+
+ if ((insn & 0x0e5f0000) == 0x041f0000) /* ldr Rd, #immed */
+ {
+ address = bits (insn, 0, 11);
+ *destreg = bits (insn, 12, 15);
+ *offset = 4;
+ }
+ else if ((insn & 0x0ff00000) == 0x03000000) /* movw Rd, #const */
+ {
+ low = EXTRACT_MOVW_MOVT_IMM_A (insn);
+
+ insn
+ = read_memory_unsigned_integer (pc + 4, 4, byte_order_for_code);
+
+ if ((insn & 0x0ff00000) == 0x03400000) /* movt Rd, #const */
+ {
+ high = EXTRACT_MOVW_MOVT_IMM_A (insn);
+ *destreg = bits (insn, 12, 15);
+ *offset = 8;
+ address = (high << 16 | low);
+ }
+ }
+ }
+
+ return address;
+}
+
+/* Try to skip a sequence of instructions used for stack protector. If PC
+ points to the first instruction of this sequence, return the address of
+ first instruction after this sequence, otherwise, return original PC.
+
+ On arm, this sequence of instructions is composed of mainly three steps,
+ Step 1: load symbol __stack_chk_guard,
+ Step 2: load from address of __stack_chk_guard,
+ Step 3: store it to somewhere else.
+
+ Usually, instructions on step 2 and step 3 are the same on various ARM
+ architectures. On step 2, it is one instruction 'ldr Rx, [Rn, #0]', and
+ on step 3, it is also one instruction 'str Rx, [r7, #immd]'. However,
+ instructions in step 1 vary from different ARM architectures. On ARMv7,
+ they are,
+
+ movw Rn, #:lower16:__stack_chk_guard
+ movt Rn, #:upper16:__stack_chk_guard
+
+ On ARMv5t, it is,
+
+ ldr Rn, .Label
+ ....
+ .Lable:
+ .word __stack_chk_guard
+
+ Since ldr/str is a very popular instruction, we can't use them as
+ 'fingerprint' or 'signature' of stack protector sequence. Here we choose
+ sequence {movw/movt, ldr}/ldr/str plus symbol __stack_chk_guard, if not
+ stripped, as the 'fingerprint' of a stack protector cdoe sequence. */
+
+static CORE_ADDR
+arm_skip_stack_protector(CORE_ADDR pc, struct gdbarch *gdbarch)
+{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned int address, basereg;
+ struct minimal_symbol *stack_chk_guard;
+ int offset;
+ int is_thumb = arm_pc_is_thumb (gdbarch, pc);
+ CORE_ADDR addr;
+
+ /* Try to parse the instructions in Step 1. */
+ addr = arm_analyze_load_stack_chk_guard (pc, gdbarch,
+ &basereg, &offset);
+ if (!addr)
+ return pc;
+
+ stack_chk_guard = lookup_minimal_symbol_by_pc (addr);
+ /* If name of symbol doesn't start with '__stack_chk_guard', this
+ instruction sequence is not for stack protector. If symbol is
+ removed, we conservatively think this sequence is for stack protector. */
+ if (stack_chk_guard
+ && strncmp (SYMBOL_LINKAGE_NAME (stack_chk_guard), "__stack_chk_guard",
+ strlen ("__stack_chk_guard")) != 0)
+ return pc;
+
+ if (is_thumb)
+ {
+ unsigned int destreg;
+ unsigned short insn
+ = read_memory_unsigned_integer (pc + offset, 2, byte_order_for_code);
+
+ /* Step 2: ldr Rd, [Rn, #immed], encoding T1. */
+ if ((insn & 0xf800) != 0x6800)
+ return pc;
+ if (bits (insn, 3, 5) != basereg)
+ return pc;
+ destreg = bits (insn, 0, 2);
+
+ insn = read_memory_unsigned_integer (pc + offset + 2, 2,
+ byte_order_for_code);
+ /* Step 3: str Rd, [Rn, #immed], encoding T1. */
+ if ((insn & 0xf800) != 0x6000)
+ return pc;
+ if (destreg != bits (insn, 0, 2))
+ return pc;
+ }
+ else
+ {
+ unsigned int destreg;
+ unsigned int insn
+ = read_memory_unsigned_integer (pc + offset, 4, byte_order_for_code);
+
+ /* Step 2: ldr Rd, [Rn, #immed], encoding A1. */
+ if ((insn & 0x0e500000) != 0x04100000)
+ return pc;
+ if (bits (insn, 16, 19) != basereg)
+ return pc;
+ destreg = bits (insn, 12, 15);
+ /* Step 3: str Rd, [Rn, #immed], encoding A1. */
+ insn = read_memory_unsigned_integer (pc + offset + 4,
+ 4, byte_order_for_code);
+ if ((insn & 0x0e500000) != 0x04000000)
+ return pc;
+ if (bits (insn, 12, 15) != destreg)
+ return pc;
+ }
+ /* The size of total two instructions ldr/str is 4 on Thumb-2, while 8
+ on arm. */
+ if (is_thumb)
+ return pc + offset + 4;
+ else
+ return pc + offset + 8;
+}
+
+/* Advance the PC across any function entry prologue instructions to
+ reach some "real" code.
+
+ The APCS (ARM Procedure Call Standard) defines the following
+ prologue:
+
+ mov ip, sp
+ [stmfd sp!, {a1,a2,a3,a4}]
+ stmfd sp!, {...,fp,ip,lr,pc}
+ [stfe f7, [sp, #-12]!]
+ [stfe f6, [sp, #-12]!]
+ [stfe f5, [sp, #-12]!]
+ [stfe f4, [sp, #-12]!]
+ sub fp, ip, #nn @@ nn == 20 or 4 depending on second insn. */
+
+static CORE_ADDR
+arm_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned long inst;
+ CORE_ADDR skip_pc;
+ CORE_ADDR func_addr, limit_pc;
+ struct symtab_and_line sal;
+
+ /* See if we can determine the end of the prologue via the symbol table.
+ If so, then return either PC, or the PC after the prologue, whichever
+ is greater. */
+ if (find_pc_partial_function (pc, NULL, &func_addr, NULL))
{
CORE_ADDR post_prologue_pc
= skip_prologue_using_sal (gdbarch, func_addr);
struct symtab *s = find_pc_symtab (func_addr);
+ if (post_prologue_pc)
+ post_prologue_pc
+ = arm_skip_stack_protector (post_prologue_pc, gdbarch);
+
+
/* GCC always emits a line note before the prologue and another
one after, even if the two are at the same address or on the
same line. Take advantage of this so that we do not need to
associate prologue code with the opening brace; so this
lets us skip the first line if we think it is the opening
brace. */
- if (arm_pc_is_thumb (func_addr))
+ if (arm_pc_is_thumb (gdbarch, func_addr))
analyzed_limit = thumb_analyze_prologue (gdbarch, func_addr,
post_prologue_pc, NULL);
else
/* Find an upper limit on the function prologue using the debug
information. If the debug information could not be used to provide
that bound, then use an arbitrary large number as the upper bound. */
- /* Like arm_scan_prologue, stop no later than pc + 64. */
+ /* Like arm_scan_prologue, stop no later than pc + 64. */
limit_pc = skip_prologue_using_sal (gdbarch, pc);
if (limit_pc == 0)
limit_pc = pc + 64; /* Magic. */
/* Check if this is Thumb code. */
- if (arm_pc_is_thumb (pc))
+ if (arm_pc_is_thumb (gdbarch, pc))
return thumb_analyze_prologue (gdbarch, pc, limit_pc, NULL);
for (skip_pc = pc; skip_pc < limit_pc; skip_pc += 4)
break;
}
- return skip_pc; /* End of prologue */
+ return skip_pc; /* End of prologue. */
}
/* *INDENT-OFF* */
R7 -> 0 local variables (16 bytes)
SP -> -12 additional stack space (12 bytes)
The frame size would thus be 36 bytes, and the frame offset would be
- 12 bytes. The frame register is R7.
+ 12 bytes. The frame register is R7.
The comments for thumb_skip_prolog() describe the algorithm we use
to detect the end of the prolog. */
if (find_pc_partial_function (block_addr, NULL, &prologue_start,
&prologue_end))
{
- struct symtab_and_line sal = find_pc_line (prologue_start, 0);
-
- if (sal.line == 0) /* no line info, use current PC */
- prologue_end = prev_pc;
- else if (sal.end < prologue_end) /* next line begins after fn end */
- prologue_end = sal.end; /* (probably means no prologue) */
+ /* See comment in arm_scan_prologue for an explanation of
+ this heuristics. */
+ if (prologue_end > prologue_start + 64)
+ {
+ prologue_end = prologue_start + 64;
+ }
}
else
/* We're in the boondocks: we have no idea where the start of the
return 0;
default:
- internal_error (__FILE__, __LINE__, "bad value in switch");
+ internal_error (__FILE__, __LINE__, _("bad value in switch"));
}
}
regs[rd] = pv_add_constant (regs[bits (insn, 16, 19)], -imm);
continue;
}
- else if ((insn & 0xffff0fff) == 0xe52d0004) /* str Rd, [sp, #-4]! */
+ else if ((insn & 0xffff0fff) == 0xe52d0004) /* str Rd,
+ [sp, #-4]! */
{
if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM]))
break;
for (regno = ARM_PC_REGNUM; regno >= 0; regno--)
if (mask & (1 << regno))
{
- regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -4);
+ regs[ARM_SP_REGNUM]
+ = pv_add_constant (regs[ARM_SP_REGNUM], -4);
pv_area_store (stack, regs[ARM_SP_REGNUM], 4, regs[regno]);
}
}
/* No need to add this to saved_regs -- it's just an arg reg. */
continue;
}
- else if ((insn & 0xfff00000) == 0xe8800000 /* stm Rn, { registers } */
+ else if ((insn & 0xfff00000) == 0xe8800000 /* stm Rn,
+ { registers } */
&& pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
{
/* No need to add this to saved_regs -- it's just arg regs. */
imm = (imm >> rot) | (imm << (32 - rot));
regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -imm);
}
- else if ((insn & 0xffff7fff) == 0xed6d0103 /* stfe f?, [sp, -#c]! */
+ else if ((insn & 0xffff7fff) == 0xed6d0103 /* stfe f?,
+ [sp, -#c]! */
&& gdbarch_tdep (gdbarch)->have_fpa_registers)
{
if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM]))
regno = ARM_F0_REGNUM + ((insn >> 12) & 0x07);
pv_area_store (stack, regs[ARM_SP_REGNUM], 12, regs[regno]);
}
- else if ((insn & 0xffbf0fff) == 0xec2d0200 /* sfmfd f0, 4, [sp!] */
+ else if ((insn & 0xffbf0fff) == 0xec2d0200 /* sfmfd f0, 4,
+ [sp!] */
&& gdbarch_tdep (gdbarch)->have_fpa_registers)
{
int n_saved_fp_regs;
the stack. */
CORE_ADDR dest = BranchDest (current_pc, insn);
- if (skip_prologue_function (dest))
+ if (skip_prologue_function (gdbarch, dest, 0))
continue;
else
break;
}
else if ((insn & 0xf0000000) != 0xe0000000)
- break; /* Condition not true, exit early */
+ break; /* Condition not true, exit early. */
else if (arm_instruction_changes_pc (insn))
/* Don't scan past anything that might change control flow. */
break;
- else if ((insn & 0xfe500000) == 0xe8100000) /* ldm */
- {
- /* Ignore block loads from the stack, potentially copying
- parameters from memory. */
- if (pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
- continue;
- else
- break;
- }
- else if ((insn & 0xfc500000) == 0xe4100000)
- {
- /* Similarly ignore single loads from the stack. */
- if (pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
- continue;
- else
- break;
- }
+ else if ((insn & 0xfe500000) == 0xe8100000 /* ldm */
+ && pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
+ /* Ignore block loads from the stack, potentially copying
+ parameters from memory. */
+ continue;
+ else if ((insn & 0xfc500000) == 0xe4100000
+ && pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
+ /* Similarly ignore single loads from the stack. */
+ continue;
else if ((insn & 0xffff0ff0) == 0xe1a00000)
/* MOV Rd, Rm. Skip register copies, i.e. saves to another
register instead of the stack. */
if (cache->prev_sp == 0)
return;
+ /* Use function start address as part of the frame ID. If we cannot
+ identify the start address (due to missing symbol information),
+ fall back to just using the current PC. */
func = get_frame_func (this_frame);
+ if (!func)
+ func = pc;
+
id = frame_id_build (cache->prev_sp, func);
*this_id = id;
}
if (prev_regnum == ARM_PS_REGNUM)
{
CORE_ADDR lr, cpsr;
+ ULONGEST t_bit = arm_psr_thumb_bit (gdbarch);
cpsr = get_frame_register_unsigned (this_frame, prev_regnum);
lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
if (IS_THUMB_ADDR (lr))
- cpsr |= CPSR_T;
+ cpsr |= t_bit;
else
- cpsr &= ~CPSR_T;
+ cpsr &= ~t_bit;
return frame_unwind_got_constant (this_frame, prev_regnum, cpsr);
}
struct frame_unwind arm_prologue_unwind = {
NORMAL_FRAME,
+ default_frame_unwind_stop_reason,
arm_prologue_this_id,
arm_prologue_prev_register,
NULL,
default_frame_sniffer
};
-static struct arm_prologue_cache *
-arm_make_stub_cache (struct frame_info *this_frame)
-{
- struct arm_prologue_cache *cache;
-
- cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache);
- cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
+/* Maintain a list of ARM exception table entries per objfile, similar to the
+ list of mapping symbols. We only cache entries for standard ARM-defined
+ personality routines; the cache will contain only the frame unwinding
+ instructions associated with the entry (not the descriptors). */
- cache->prev_sp = get_frame_register_unsigned (this_frame, ARM_SP_REGNUM);
+static const struct objfile_data *arm_exidx_data_key;
- return cache;
-}
+struct arm_exidx_entry
+{
+ bfd_vma addr;
+ gdb_byte *entry;
+};
+typedef struct arm_exidx_entry arm_exidx_entry_s;
+DEF_VEC_O(arm_exidx_entry_s);
-/* Our frame ID for a stub frame is the current SP and LR. */
+struct arm_exidx_data
+{
+ VEC(arm_exidx_entry_s) **section_maps;
+};
static void
-arm_stub_this_id (struct frame_info *this_frame,
- void **this_cache,
- struct frame_id *this_id)
+arm_exidx_data_free (struct objfile *objfile, void *arg)
{
- struct arm_prologue_cache *cache;
-
- if (*this_cache == NULL)
- *this_cache = arm_make_stub_cache (this_frame);
- cache = *this_cache;
+ struct arm_exidx_data *data = arg;
+ unsigned int i;
- *this_id = frame_id_build (cache->prev_sp, get_frame_pc (this_frame));
+ for (i = 0; i < objfile->obfd->section_count; i++)
+ VEC_free (arm_exidx_entry_s, data->section_maps[i]);
}
-static int
-arm_stub_unwind_sniffer (const struct frame_unwind *self,
- struct frame_info *this_frame,
- void **this_prologue_cache)
+static inline int
+arm_compare_exidx_entries (const struct arm_exidx_entry *lhs,
+ const struct arm_exidx_entry *rhs)
{
- CORE_ADDR addr_in_block;
- char dummy[4];
-
- addr_in_block = get_frame_address_in_block (this_frame);
- if (in_plt_section (addr_in_block, NULL)
- /* We also use the stub winder if the target memory is unreadable
- to avoid having the prologue unwinder trying to read it. */
- || target_read_memory (get_frame_pc (this_frame), dummy, 4) != 0)
- return 1;
-
- return 0;
+ return lhs->addr < rhs->addr;
}
-struct frame_unwind arm_stub_unwind = {
- NORMAL_FRAME,
- arm_stub_this_id,
- arm_prologue_prev_register,
- NULL,
- arm_stub_unwind_sniffer
-};
-
-static CORE_ADDR
-arm_normal_frame_base (struct frame_info *this_frame, void **this_cache)
+static struct obj_section *
+arm_obj_section_from_vma (struct objfile *objfile, bfd_vma vma)
{
- struct arm_prologue_cache *cache;
-
- if (*this_cache == NULL)
- *this_cache = arm_make_prologue_cache (this_frame);
- cache = *this_cache;
-
- return cache->prev_sp - cache->framesize;
-}
+ struct obj_section *osect;
-struct frame_base arm_normal_base = {
- &arm_prologue_unwind,
- arm_normal_frame_base,
- arm_normal_frame_base,
- arm_normal_frame_base
-};
+ ALL_OBJFILE_OSECTIONS (objfile, osect)
+ if (bfd_get_section_flags (objfile->obfd,
+ osect->the_bfd_section) & SEC_ALLOC)
+ {
+ bfd_vma start, size;
+ start = bfd_get_section_vma (objfile->obfd, osect->the_bfd_section);
+ size = bfd_get_section_size (osect->the_bfd_section);
-/* Assuming THIS_FRAME is a dummy, return the frame ID of that
- dummy frame. The frame ID's base needs to match the TOS value
- saved by save_dummy_frame_tos() and returned from
- arm_push_dummy_call, and the PC needs to match the dummy frame's
- breakpoint. */
+ if (start <= vma && vma < start + size)
+ return osect;
+ }
-static struct frame_id
-arm_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
-{
- return frame_id_build (get_frame_register_unsigned (this_frame, ARM_SP_REGNUM),
- get_frame_pc (this_frame));
+ return NULL;
}
-/* Given THIS_FRAME, find the previous frame's resume PC (which will
- be used to construct the previous frame's ID, after looking up the
- containing function). */
-
-static CORE_ADDR
-arm_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame)
-{
- CORE_ADDR pc;
- pc = frame_unwind_register_unsigned (this_frame, ARM_PC_REGNUM);
- return arm_addr_bits_remove (gdbarch, pc);
-}
+/* Parse contents of exception table and exception index sections
+ of OBJFILE, and fill in the exception table entry cache.
-static CORE_ADDR
-arm_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
-{
- return frame_unwind_register_unsigned (this_frame, ARM_SP_REGNUM);
-}
+ For each entry that refers to a standard ARM-defined personality
+ routine, extract the frame unwinding instructions (from either
+ the index or the table section). The unwinding instructions
+ are normalized by:
+ - extracting them from the rest of the table data
+ - converting to host endianness
+ - appending the implicit 0xb0 ("Finish") code
-static struct value *
-arm_dwarf2_prev_register (struct frame_info *this_frame, void **this_cache,
- int regnum)
-{
- struct gdbarch * gdbarch = get_frame_arch (this_frame);
- CORE_ADDR lr, cpsr;
+ The extracted and normalized instructions are stored for later
+ retrieval by the arm_find_exidx_entry routine. */
+
+static void
+arm_exidx_new_objfile (struct objfile *objfile)
+{
+ struct cleanup *cleanups;
+ struct arm_exidx_data *data;
+ asection *exidx, *extab;
+ bfd_vma exidx_vma = 0, extab_vma = 0;
+ bfd_size_type exidx_size = 0, extab_size = 0;
+ gdb_byte *exidx_data = NULL, *extab_data = NULL;
+ LONGEST i;
+
+ /* If we've already touched this file, do nothing. */
+ if (!objfile || objfile_data (objfile, arm_exidx_data_key) != NULL)
+ return;
+ cleanups = make_cleanup (null_cleanup, NULL);
- switch (regnum)
+ /* Read contents of exception table and index. */
+ exidx = bfd_get_section_by_name (objfile->obfd, ".ARM.exidx");
+ if (exidx)
{
- case ARM_PC_REGNUM:
- /* The PC is normally copied from the return column, which
- describes saves of LR. However, that version may have an
- extra bit set to indicate Thumb state. The bit is not
- part of the PC. */
- lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
- return frame_unwind_got_constant (this_frame, regnum,
- arm_addr_bits_remove (gdbarch, lr));
+ exidx_vma = bfd_section_vma (objfile->obfd, exidx);
+ exidx_size = bfd_get_section_size (exidx);
+ exidx_data = xmalloc (exidx_size);
+ make_cleanup (xfree, exidx_data);
- case ARM_PS_REGNUM:
- /* Reconstruct the T bit; see arm_prologue_prev_register for details. */
- cpsr = get_frame_register_unsigned (this_frame, regnum);
- lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
- if (IS_THUMB_ADDR (lr))
- cpsr |= CPSR_T;
- else
- cpsr &= ~CPSR_T;
- return frame_unwind_got_constant (this_frame, regnum, cpsr);
-
- default:
- internal_error (__FILE__, __LINE__,
- _("Unexpected register %d"), regnum);
+ if (!bfd_get_section_contents (objfile->obfd, exidx,
+ exidx_data, 0, exidx_size))
+ {
+ do_cleanups (cleanups);
+ return;
+ }
}
-}
-static void
-arm_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
- struct dwarf2_frame_state_reg *reg,
- struct frame_info *this_frame)
-{
- switch (regnum)
+ extab = bfd_get_section_by_name (objfile->obfd, ".ARM.extab");
+ if (extab)
{
- case ARM_PC_REGNUM:
- case ARM_PS_REGNUM:
- reg->how = DWARF2_FRAME_REG_FN;
- reg->loc.fn = arm_dwarf2_prev_register;
- break;
- case ARM_SP_REGNUM:
- reg->how = DWARF2_FRAME_REG_CFA;
- break;
+ extab_vma = bfd_section_vma (objfile->obfd, extab);
+ extab_size = bfd_get_section_size (extab);
+ extab_data = xmalloc (extab_size);
+ make_cleanup (xfree, extab_data);
+
+ if (!bfd_get_section_contents (objfile->obfd, extab,
+ extab_data, 0, extab_size))
+ {
+ do_cleanups (cleanups);
+ return;
+ }
}
-}
-/* When arguments must be pushed onto the stack, they go on in reverse
- order. The code below implements a FILO (stack) to do this. */
+ /* Allocate exception table data structure. */
+ data = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct arm_exidx_data);
+ set_objfile_data (objfile, arm_exidx_data_key, data);
+ data->section_maps = OBSTACK_CALLOC (&objfile->objfile_obstack,
+ objfile->obfd->section_count,
+ VEC(arm_exidx_entry_s) *);
-struct stack_item
-{
- int len;
- struct stack_item *prev;
- void *data;
-};
+ /* Fill in exception table. */
+ for (i = 0; i < exidx_size / 8; i++)
+ {
+ struct arm_exidx_entry new_exidx_entry;
+ bfd_vma idx = bfd_h_get_32 (objfile->obfd, exidx_data + i * 8);
+ bfd_vma val = bfd_h_get_32 (objfile->obfd, exidx_data + i * 8 + 4);
+ bfd_vma addr = 0, word = 0;
+ int n_bytes = 0, n_words = 0;
+ struct obj_section *sec;
+ gdb_byte *entry = NULL;
-static struct stack_item *
-push_stack_item (struct stack_item *prev, void *contents, int len)
-{
- struct stack_item *si;
- si = xmalloc (sizeof (struct stack_item));
- si->data = xmalloc (len);
- si->len = len;
- si->prev = prev;
- memcpy (si->data, contents, len);
- return si;
-}
-
-static struct stack_item *
-pop_stack_item (struct stack_item *si)
-{
- struct stack_item *dead = si;
- si = si->prev;
- xfree (dead->data);
- xfree (dead);
- return si;
-}
+ /* Extract address of start of function. */
+ idx = ((idx & 0x7fffffff) ^ 0x40000000) - 0x40000000;
+ idx += exidx_vma + i * 8;
+ /* Find section containing function and compute section offset. */
+ sec = arm_obj_section_from_vma (objfile, idx);
+ if (sec == NULL)
+ continue;
+ idx -= bfd_get_section_vma (objfile->obfd, sec->the_bfd_section);
-/* Return the alignment (in bytes) of the given type. */
+ /* Determine address of exception table entry. */
+ if (val == 1)
+ {
+ /* EXIDX_CANTUNWIND -- no exception table entry present. */
+ }
+ else if ((val & 0xff000000) == 0x80000000)
+ {
+ /* Exception table entry embedded in .ARM.exidx
+ -- must be short form. */
+ word = val;
+ n_bytes = 3;
+ }
+ else if (!(val & 0x80000000))
+ {
+ /* Exception table entry in .ARM.extab. */
+ addr = ((val & 0x7fffffff) ^ 0x40000000) - 0x40000000;
+ addr += exidx_vma + i * 8 + 4;
-static int
-arm_type_align (struct type *t)
-{
- int n;
- int align;
- int falign;
+ if (addr >= extab_vma && addr + 4 <= extab_vma + extab_size)
+ {
+ word = bfd_h_get_32 (objfile->obfd,
+ extab_data + addr - extab_vma);
+ addr += 4;
- t = check_typedef (t);
- switch (TYPE_CODE (t))
- {
- default:
- /* Should never happen. */
- internal_error (__FILE__, __LINE__, _("unknown type alignment"));
- return 4;
+ if ((word & 0xff000000) == 0x80000000)
+ {
+ /* Short form. */
+ n_bytes = 3;
+ }
+ else if ((word & 0xff000000) == 0x81000000
+ || (word & 0xff000000) == 0x82000000)
+ {
+ /* Long form. */
+ n_bytes = 2;
+ n_words = ((word >> 16) & 0xff);
+ }
+ else if (!(word & 0x80000000))
+ {
+ bfd_vma pers;
+ struct obj_section *pers_sec;
+ int gnu_personality = 0;
+
+ /* Custom personality routine. */
+ pers = ((word & 0x7fffffff) ^ 0x40000000) - 0x40000000;
+ pers = UNMAKE_THUMB_ADDR (pers + addr - 4);
+
+ /* Check whether we've got one of the variants of the
+ GNU personality routines. */
+ pers_sec = arm_obj_section_from_vma (objfile, pers);
+ if (pers_sec)
+ {
+ static const char *personality[] =
+ {
+ "__gcc_personality_v0",
+ "__gxx_personality_v0",
+ "__gcj_personality_v0",
+ "__gnu_objc_personality_v0",
+ NULL
+ };
+
+ CORE_ADDR pc = pers + obj_section_offset (pers_sec);
+ int k;
+
+ for (k = 0; personality[k]; k++)
+ if (lookup_minimal_symbol_by_pc_name
+ (pc, personality[k], objfile))
+ {
+ gnu_personality = 1;
+ break;
+ }
+ }
- case TYPE_CODE_PTR:
- case TYPE_CODE_ENUM:
- case TYPE_CODE_INT:
- case TYPE_CODE_FLT:
- case TYPE_CODE_SET:
- case TYPE_CODE_RANGE:
- case TYPE_CODE_BITSTRING:
- case TYPE_CODE_REF:
- case TYPE_CODE_CHAR:
- case TYPE_CODE_BOOL:
- return TYPE_LENGTH (t);
+ /* If so, the next word contains a word count in the high
+ byte, followed by the same unwind instructions as the
+ pre-defined forms. */
+ if (gnu_personality
+ && addr + 4 <= extab_vma + extab_size)
+ {
+ word = bfd_h_get_32 (objfile->obfd,
+ extab_data + addr - extab_vma);
+ addr += 4;
+ n_bytes = 3;
+ n_words = ((word >> 24) & 0xff);
+ }
+ }
+ }
+ }
- case TYPE_CODE_ARRAY:
- case TYPE_CODE_COMPLEX:
- /* TODO: What about vector types? */
- return arm_type_align (TYPE_TARGET_TYPE (t));
+ /* Sanity check address. */
+ if (n_words)
+ if (addr < extab_vma || addr + 4 * n_words > extab_vma + extab_size)
+ n_words = n_bytes = 0;
- case TYPE_CODE_STRUCT:
- case TYPE_CODE_UNION:
- align = 1;
- for (n = 0; n < TYPE_NFIELDS (t); n++)
+ /* The unwind instructions reside in WORD (only the N_BYTES least
+ significant bytes are valid), followed by N_WORDS words in the
+ extab section starting at ADDR. */
+ if (n_bytes || n_words)
{
- falign = arm_type_align (TYPE_FIELD_TYPE (t, n));
- if (falign > align)
- align = falign;
- }
- return align;
- }
-}
+ gdb_byte *p = entry = obstack_alloc (&objfile->objfile_obstack,
+ n_bytes + n_words * 4 + 1);
-/* Possible base types for a candidate for passing and returning in
- VFP registers. */
+ while (n_bytes--)
+ *p++ = (gdb_byte) ((word >> (8 * n_bytes)) & 0xff);
-enum arm_vfp_cprc_base_type
-{
- VFP_CPRC_UNKNOWN,
- VFP_CPRC_SINGLE,
- VFP_CPRC_DOUBLE,
- VFP_CPRC_VEC64,
- VFP_CPRC_VEC128
-};
+ while (n_words--)
+ {
+ word = bfd_h_get_32 (objfile->obfd,
+ extab_data + addr - extab_vma);
+ addr += 4;
+
+ *p++ = (gdb_byte) ((word >> 24) & 0xff);
+ *p++ = (gdb_byte) ((word >> 16) & 0xff);
+ *p++ = (gdb_byte) ((word >> 8) & 0xff);
+ *p++ = (gdb_byte) (word & 0xff);
+ }
-/* The length of one element of base type B. */
+ /* Implied "Finish" to terminate the list. */
+ *p++ = 0xb0;
+ }
-static unsigned
-arm_vfp_cprc_unit_length (enum arm_vfp_cprc_base_type b)
-{
- switch (b)
- {
- case VFP_CPRC_SINGLE:
- return 4;
- case VFP_CPRC_DOUBLE:
- return 8;
- case VFP_CPRC_VEC64:
- return 8;
- case VFP_CPRC_VEC128:
- return 16;
- default:
- internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."),
- (int) b);
+ /* Push entry onto vector. They are guaranteed to always
+ appear in order of increasing addresses. */
+ new_exidx_entry.addr = idx;
+ new_exidx_entry.entry = entry;
+ VEC_safe_push (arm_exidx_entry_s,
+ data->section_maps[sec->the_bfd_section->index],
+ &new_exidx_entry);
}
+
+ do_cleanups (cleanups);
}
-/* The character ('s', 'd' or 'q') for the type of VFP register used
- for passing base type B. */
+/* Search for the exception table entry covering MEMADDR. If one is found,
+ return a pointer to its data. Otherwise, return 0. If START is non-NULL,
+ set *START to the start of the region covered by this entry. */
-static int
-arm_vfp_cprc_reg_char (enum arm_vfp_cprc_base_type b)
+static gdb_byte *
+arm_find_exidx_entry (CORE_ADDR memaddr, CORE_ADDR *start)
{
- switch (b)
+ struct obj_section *sec;
+
+ sec = find_pc_section (memaddr);
+ if (sec != NULL)
{
- case VFP_CPRC_SINGLE:
- return 's';
- case VFP_CPRC_DOUBLE:
- return 'd';
- case VFP_CPRC_VEC64:
- return 'd';
- case VFP_CPRC_VEC128:
- return 'q';
- default:
- internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."),
- (int) b);
+ struct arm_exidx_data *data;
+ VEC(arm_exidx_entry_s) *map;
+ struct arm_exidx_entry map_key = { memaddr - obj_section_addr (sec), 0 };
+ unsigned int idx;
+
+ data = objfile_data (sec->objfile, arm_exidx_data_key);
+ if (data != NULL)
+ {
+ map = data->section_maps[sec->the_bfd_section->index];
+ if (!VEC_empty (arm_exidx_entry_s, map))
+ {
+ struct arm_exidx_entry *map_sym;
+
+ idx = VEC_lower_bound (arm_exidx_entry_s, map, &map_key,
+ arm_compare_exidx_entries);
+
+ /* VEC_lower_bound finds the earliest ordered insertion
+ point. If the following symbol starts at this exact
+ address, we use that; otherwise, the preceding
+ exception table entry covers this address. */
+ if (idx < VEC_length (arm_exidx_entry_s, map))
+ {
+ map_sym = VEC_index (arm_exidx_entry_s, map, idx);
+ if (map_sym->addr == map_key.addr)
+ {
+ if (start)
+ *start = map_sym->addr + obj_section_addr (sec);
+ return map_sym->entry;
+ }
+ }
+
+ if (idx > 0)
+ {
+ map_sym = VEC_index (arm_exidx_entry_s, map, idx - 1);
+ if (start)
+ *start = map_sym->addr + obj_section_addr (sec);
+ return map_sym->entry;
+ }
+ }
+ }
}
+
+ return NULL;
}
-/* Determine whether T may be part of a candidate for passing and
- returning in VFP registers, ignoring the limit on the total number
- of components. If *BASE_TYPE is VFP_CPRC_UNKNOWN, set it to the
- classification of the first valid component found; if it is not
- VFP_CPRC_UNKNOWN, all components must have the same classification
- as *BASE_TYPE. If it is found that T contains a type not permitted
- for passing and returning in VFP registers, a type differently
- classified from *BASE_TYPE, or two types differently classified
- from each other, return -1, otherwise return the total number of
- base-type elements found (possibly 0 in an empty structure or
- array). Vectors and complex types are not currently supported,
- matching the generic AAPCS support. */
+/* Given the current frame THIS_FRAME, and its associated frame unwinding
+ instruction list from the ARM exception table entry ENTRY, allocate and
+ return a prologue cache structure describing how to unwind this frame.
-static int
-arm_vfp_cprc_sub_candidate (struct type *t,
- enum arm_vfp_cprc_base_type *base_type)
+ Return NULL if the unwinding instruction list contains a "spare",
+ "reserved" or "refuse to unwind" instruction as defined in section
+ "9.3 Frame unwinding instructions" of the "Exception Handling ABI
+ for the ARM Architecture" document. */
+
+static struct arm_prologue_cache *
+arm_exidx_fill_cache (struct frame_info *this_frame, gdb_byte *entry)
{
- t = check_typedef (t);
- switch (TYPE_CODE (t))
+ CORE_ADDR vsp = 0;
+ int vsp_valid = 0;
+
+ struct arm_prologue_cache *cache;
+ cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache);
+ cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
+
+ for (;;)
{
- case TYPE_CODE_FLT:
- switch (TYPE_LENGTH (t))
+ gdb_byte insn;
+
+ /* Whenever we reload SP, we actually have to retrieve its
+ actual value in the current frame. */
+ if (!vsp_valid)
{
- case 4:
- if (*base_type == VFP_CPRC_UNKNOWN)
- *base_type = VFP_CPRC_SINGLE;
- else if (*base_type != VFP_CPRC_SINGLE)
- return -1;
- return 1;
+ if (trad_frame_realreg_p (cache->saved_regs, ARM_SP_REGNUM))
+ {
+ int reg = cache->saved_regs[ARM_SP_REGNUM].realreg;
+ vsp = get_frame_register_unsigned (this_frame, reg);
+ }
+ else
+ {
+ CORE_ADDR addr = cache->saved_regs[ARM_SP_REGNUM].addr;
+ vsp = get_frame_memory_unsigned (this_frame, addr, 4);
+ }
- case 8:
- if (*base_type == VFP_CPRC_UNKNOWN)
- *base_type = VFP_CPRC_DOUBLE;
- else if (*base_type != VFP_CPRC_DOUBLE)
- return -1;
- return 1;
+ vsp_valid = 1;
+ }
- default:
- return -1;
+ /* Decode next unwind instruction. */
+ insn = *entry++;
+
+ if ((insn & 0xc0) == 0)
+ {
+ int offset = insn & 0x3f;
+ vsp += (offset << 2) + 4;
}
- break;
+ else if ((insn & 0xc0) == 0x40)
+ {
+ int offset = insn & 0x3f;
+ vsp -= (offset << 2) + 4;
+ }
+ else if ((insn & 0xf0) == 0x80)
+ {
+ int mask = ((insn & 0xf) << 8) | *entry++;
+ int i;
+
+ /* The special case of an all-zero mask identifies
+ "Refuse to unwind". We return NULL to fall back
+ to the prologue analyzer. */
+ if (mask == 0)
+ return NULL;
+
+ /* Pop registers r4..r15 under mask. */
+ for (i = 0; i < 12; i++)
+ if (mask & (1 << i))
+ {
+ cache->saved_regs[4 + i].addr = vsp;
+ vsp += 4;
+ }
- case TYPE_CODE_ARRAY:
- {
- int count;
- unsigned unitlen;
- count = arm_vfp_cprc_sub_candidate (TYPE_TARGET_TYPE (t), base_type);
- if (count == -1)
- return -1;
- if (TYPE_LENGTH (t) == 0)
- {
- gdb_assert (count == 0);
- return 0;
- }
- else if (count == 0)
- return -1;
- unitlen = arm_vfp_cprc_unit_length (*base_type);
- gdb_assert ((TYPE_LENGTH (t) % unitlen) == 0);
- return TYPE_LENGTH (t) / unitlen;
- }
- break;
+ /* Special-case popping SP -- we need to reload vsp. */
+ if (mask & (1 << (ARM_SP_REGNUM - 4)))
+ vsp_valid = 0;
+ }
+ else if ((insn & 0xf0) == 0x90)
+ {
+ int reg = insn & 0xf;
- case TYPE_CODE_STRUCT:
- {
- int count = 0;
- unsigned unitlen;
- int i;
- for (i = 0; i < TYPE_NFIELDS (t); i++)
- {
- int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i),
- base_type);
- if (sub_count == -1)
- return -1;
- count += sub_count;
- }
- if (TYPE_LENGTH (t) == 0)
- {
- gdb_assert (count == 0);
- return 0;
- }
- else if (count == 0)
- return -1;
- unitlen = arm_vfp_cprc_unit_length (*base_type);
- if (TYPE_LENGTH (t) != unitlen * count)
- return -1;
- return count;
- }
+ /* Reserved cases. */
+ if (reg == ARM_SP_REGNUM || reg == ARM_PC_REGNUM)
+ return NULL;
- case TYPE_CODE_UNION:
- {
- int count = 0;
- unsigned unitlen;
- int i;
- for (i = 0; i < TYPE_NFIELDS (t); i++)
- {
- int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i),
- base_type);
- if (sub_count == -1)
- return -1;
- count = (count > sub_count ? count : sub_count);
- }
- if (TYPE_LENGTH (t) == 0)
- {
- gdb_assert (count == 0);
- return 0;
- }
- else if (count == 0)
- return -1;
- unitlen = arm_vfp_cprc_unit_length (*base_type);
- if (TYPE_LENGTH (t) != unitlen * count)
- return -1;
- return count;
- }
+ /* Set SP from another register and mark VSP for reload. */
+ cache->saved_regs[ARM_SP_REGNUM] = cache->saved_regs[reg];
+ vsp_valid = 0;
+ }
+ else if ((insn & 0xf0) == 0xa0)
+ {
+ int count = insn & 0x7;
+ int pop_lr = (insn & 0x8) != 0;
+ int i;
- default:
- break;
- }
+ /* Pop r4..r[4+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[4 + i].addr = vsp;
+ vsp += 4;
+ }
- return -1;
-}
+ /* If indicated by flag, pop LR as well. */
+ if (pop_lr)
+ {
+ cache->saved_regs[ARM_LR_REGNUM].addr = vsp;
+ vsp += 4;
+ }
+ }
+ else if (insn == 0xb0)
+ {
+ /* We could only have updated PC by popping into it; if so, it
+ will show up as address. Otherwise, copy LR into PC. */
+ if (!trad_frame_addr_p (cache->saved_regs, ARM_PC_REGNUM))
+ cache->saved_regs[ARM_PC_REGNUM]
+ = cache->saved_regs[ARM_LR_REGNUM];
-/* Determine whether T is a VFP co-processor register candidate (CPRC)
- if passed to or returned from a non-variadic function with the VFP
- ABI in effect. Return 1 if it is, 0 otherwise. If it is, set
- *BASE_TYPE to the base type for T and *COUNT to the number of
- elements of that base type before returning. */
+ /* We're done. */
+ break;
+ }
+ else if (insn == 0xb1)
+ {
+ int mask = *entry++;
+ int i;
-static int
-arm_vfp_call_candidate (struct type *t, enum arm_vfp_cprc_base_type *base_type,
- int *count)
-{
- enum arm_vfp_cprc_base_type b = VFP_CPRC_UNKNOWN;
- int c = arm_vfp_cprc_sub_candidate (t, &b);
- if (c <= 0 || c > 4)
- return 0;
- *base_type = b;
- *count = c;
- return 1;
-}
+ /* All-zero mask and mask >= 16 is "spare". */
+ if (mask == 0 || mask >= 16)
+ return NULL;
-/* Return 1 if the VFP ABI should be used for passing arguments to and
- returning values from a function of type FUNC_TYPE, 0
- otherwise. */
+ /* Pop r0..r3 under mask. */
+ for (i = 0; i < 4; i++)
+ if (mask & (1 << i))
+ {
+ cache->saved_regs[i].addr = vsp;
+ vsp += 4;
+ }
+ }
+ else if (insn == 0xb2)
+ {
+ ULONGEST offset = 0;
+ unsigned shift = 0;
-static int
-arm_vfp_abi_for_function (struct gdbarch *gdbarch, struct type *func_type)
-{
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- /* Variadic functions always use the base ABI. Assume that functions
- without debug info are not variadic. */
- if (func_type && TYPE_VARARGS (check_typedef (func_type)))
- return 0;
- /* The VFP ABI is only supported as a variant of AAPCS. */
- if (tdep->arm_abi != ARM_ABI_AAPCS)
- return 0;
- return gdbarch_tdep (gdbarch)->fp_model == ARM_FLOAT_VFP;
-}
+ do
+ {
+ offset |= (*entry & 0x7f) << shift;
+ shift += 7;
+ }
+ while (*entry++ & 0x80);
-/* We currently only support passing parameters in integer registers, which
- conforms with GCC's default model, and VFP argument passing following
- the VFP variant of AAPCS. Several other variants exist and
- we should probably support some of them based on the selected ABI. */
+ vsp += 0x204 + (offset << 2);
+ }
+ else if (insn == 0xb3)
+ {
+ int start = *entry >> 4;
+ int count = (*entry++) & 0xf;
+ int i;
-static CORE_ADDR
-arm_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
- struct regcache *regcache, CORE_ADDR bp_addr, int nargs,
- struct value **args, CORE_ADDR sp, int struct_return,
- CORE_ADDR struct_addr)
-{
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- int argnum;
- int argreg;
- int nstack;
- struct stack_item *si = NULL;
- int use_vfp_abi;
- struct type *ftype;
- unsigned vfp_regs_free = (1 << 16) - 1;
+ /* Only registers D0..D15 are valid here. */
+ if (start + count >= 16)
+ return NULL;
- /* Determine the type of this function and whether the VFP ABI
- applies. */
- ftype = check_typedef (value_type (function));
- if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
- ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
- use_vfp_abi = arm_vfp_abi_for_function (gdbarch, ftype);
+ /* Pop VFP double-precision registers D[start]..D[start+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_D0_REGNUM + start + i].addr = vsp;
+ vsp += 8;
+ }
- /* Set the return address. For the ARM, the return breakpoint is
- always at BP_ADDR. */
- if (arm_pc_is_thumb (bp_addr))
- bp_addr |= 1;
- regcache_cooked_write_unsigned (regcache, ARM_LR_REGNUM, bp_addr);
+ /* Add an extra 4 bytes for FSTMFDX-style stack. */
+ vsp += 4;
+ }
+ else if ((insn & 0xf8) == 0xb8)
+ {
+ int count = insn & 0x7;
+ int i;
- /* Walk through the list of args and determine how large a temporary
- stack is required. Need to take care here as structs may be
- passed on the stack, and we have to to push them. */
- nstack = 0;
+ /* Pop VFP double-precision registers D[8]..D[8+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_D0_REGNUM + 8 + i].addr = vsp;
+ vsp += 8;
+ }
- argreg = ARM_A1_REGNUM;
- nstack = 0;
+ /* Add an extra 4 bytes for FSTMFDX-style stack. */
+ vsp += 4;
+ }
+ else if (insn == 0xc6)
+ {
+ int start = *entry >> 4;
+ int count = (*entry++) & 0xf;
+ int i;
- /* The struct_return pointer occupies the first parameter
- passing register. */
- if (struct_return)
- {
- if (arm_debug)
- fprintf_unfiltered (gdb_stdlog, "struct return in %s = %s\n",
- gdbarch_register_name (gdbarch, argreg),
- paddress (gdbarch, struct_addr));
- regcache_cooked_write_unsigned (regcache, argreg, struct_addr);
- argreg++;
- }
+ /* Only registers WR0..WR15 are valid. */
+ if (start + count >= 16)
+ return NULL;
- for (argnum = 0; argnum < nargs; argnum++)
- {
- int len;
- struct type *arg_type;
- struct type *target_type;
- enum type_code typecode;
- bfd_byte *val;
- int align;
- enum arm_vfp_cprc_base_type vfp_base_type;
- int vfp_base_count;
- int may_use_core_reg = 1;
+ /* Pop iwmmx registers WR[start]..WR[start+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_WR0_REGNUM + start + i].addr = vsp;
+ vsp += 8;
+ }
+ }
+ else if (insn == 0xc7)
+ {
+ int mask = *entry++;
+ int i;
- arg_type = check_typedef (value_type (args[argnum]));
- len = TYPE_LENGTH (arg_type);
- target_type = TYPE_TARGET_TYPE (arg_type);
- typecode = TYPE_CODE (arg_type);
- val = value_contents_writeable (args[argnum]);
+ /* All-zero mask and mask >= 16 is "spare". */
+ if (mask == 0 || mask >= 16)
+ return NULL;
- align = arm_type_align (arg_type);
- /* Round alignment up to a whole number of words. */
- align = (align + INT_REGISTER_SIZE - 1) & ~(INT_REGISTER_SIZE - 1);
- /* Different ABIs have different maximum alignments. */
- if (gdbarch_tdep (gdbarch)->arm_abi == ARM_ABI_APCS)
- {
- /* The APCS ABI only requires word alignment. */
- align = INT_REGISTER_SIZE;
+ /* Pop iwmmx general-purpose registers WCGR0..WCGR3 under mask. */
+ for (i = 0; i < 4; i++)
+ if (mask & (1 << i))
+ {
+ cache->saved_regs[ARM_WCGR0_REGNUM + i].addr = vsp;
+ vsp += 4;
+ }
}
- else
+ else if ((insn & 0xf8) == 0xc0)
{
- /* The AAPCS requires at most doubleword alignment. */
- if (align > INT_REGISTER_SIZE * 2)
- align = INT_REGISTER_SIZE * 2;
- }
+ int count = insn & 0x7;
+ int i;
- if (use_vfp_abi
- && arm_vfp_call_candidate (arg_type, &vfp_base_type,
- &vfp_base_count))
+ /* Pop iwmmx registers WR[10]..WR[10+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_WR0_REGNUM + 10 + i].addr = vsp;
+ vsp += 8;
+ }
+ }
+ else if (insn == 0xc8)
{
- int regno;
- int unit_length;
- int shift;
- unsigned mask;
-
- /* Because this is a CPRC it cannot go in a core register or
- cause a core register to be skipped for alignment.
- Either it goes in VFP registers and the rest of this loop
- iteration is skipped for this argument, or it goes on the
- stack (and the stack alignment code is correct for this
- case). */
- may_use_core_reg = 0;
+ int start = *entry >> 4;
+ int count = (*entry++) & 0xf;
+ int i;
- unit_length = arm_vfp_cprc_unit_length (vfp_base_type);
- shift = unit_length / 4;
- mask = (1 << (shift * vfp_base_count)) - 1;
- for (regno = 0; regno < 16; regno += shift)
- if (((vfp_regs_free >> regno) & mask) == mask)
- break;
+ /* Only registers D0..D31 are valid. */
+ if (start + count >= 16)
+ return NULL;
- if (regno < 16)
+ /* Pop VFP double-precision registers
+ D[16+start]..D[16+start+count]. */
+ for (i = 0; i <= count; i++)
{
- int reg_char;
- int reg_scaled;
- int i;
-
- vfp_regs_free &= ~(mask << regno);
- reg_scaled = regno / shift;
- reg_char = arm_vfp_cprc_reg_char (vfp_base_type);
- for (i = 0; i < vfp_base_count; i++)
- {
- char name_buf[4];
- int regnum;
- if (reg_char == 'q')
- arm_neon_quad_write (gdbarch, regcache, reg_scaled + i,
- val + i * unit_length);
- else
- {
- sprintf (name_buf, "%c%d", reg_char, reg_scaled + i);
- regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
- strlen (name_buf));
- regcache_cooked_write (regcache, regnum,
- val + i * unit_length);
- }
- }
- continue;
+ cache->saved_regs[ARM_D0_REGNUM + 16 + start + i].addr = vsp;
+ vsp += 8;
}
- else
+ }
+ else if (insn == 0xc9)
+ {
+ int start = *entry >> 4;
+ int count = (*entry++) & 0xf;
+ int i;
+
+ /* Pop VFP double-precision registers D[start]..D[start+count]. */
+ for (i = 0; i <= count; i++)
{
- /* This CPRC could not go in VFP registers, so all VFP
- registers are now marked as used. */
- vfp_regs_free = 0;
+ cache->saved_regs[ARM_D0_REGNUM + start + i].addr = vsp;
+ vsp += 8;
}
}
-
- /* Push stack padding for dowubleword alignment. */
- if (nstack & (align - 1))
+ else if ((insn & 0xf8) == 0xd0)
{
- si = push_stack_item (si, val, INT_REGISTER_SIZE);
- nstack += INT_REGISTER_SIZE;
- }
-
- /* Doubleword aligned quantities must go in even register pairs. */
- if (may_use_core_reg
- && argreg <= ARM_LAST_ARG_REGNUM
- && align > INT_REGISTER_SIZE
- && argreg & 1)
- argreg++;
+ int count = insn & 0x7;
+ int i;
- /* If the argument is a pointer to a function, and it is a
- Thumb function, create a LOCAL copy of the value and set
- the THUMB bit in it. */
- if (TYPE_CODE_PTR == typecode
- && target_type != NULL
- && TYPE_CODE_FUNC == TYPE_CODE (target_type))
- {
- CORE_ADDR regval = extract_unsigned_integer (val, len, byte_order);
- if (arm_pc_is_thumb (regval))
+ /* Pop VFP double-precision registers D[8]..D[8+count]. */
+ for (i = 0; i <= count; i++)
{
- val = alloca (len);
- store_unsigned_integer (val, len, byte_order,
- MAKE_THUMB_ADDR (regval));
+ cache->saved_regs[ARM_D0_REGNUM + 8 + i].addr = vsp;
+ vsp += 8;
}
}
-
- /* Copy the argument to general registers or the stack in
- register-sized pieces. Large arguments are split between
- registers and stack. */
- while (len > 0)
+ else
{
- int partial_len = len < INT_REGISTER_SIZE ? len : INT_REGISTER_SIZE;
+ /* Everything else is "spare". */
+ return NULL;
+ }
+ }
- if (may_use_core_reg && argreg <= ARM_LAST_ARG_REGNUM)
- {
- /* The argument is being passed in a general purpose
- register. */
- CORE_ADDR regval
- = extract_unsigned_integer (val, partial_len, byte_order);
- if (byte_order == BFD_ENDIAN_BIG)
- regval <<= (INT_REGISTER_SIZE - partial_len) * 8;
- if (arm_debug)
- fprintf_unfiltered (gdb_stdlog, "arg %d in %s = 0x%s\n",
- argnum,
- gdbarch_register_name
- (gdbarch, argreg),
- phex (regval, INT_REGISTER_SIZE));
- regcache_cooked_write_unsigned (regcache, argreg, regval);
- argreg++;
- }
- else
- {
- /* Push the arguments onto the stack. */
- if (arm_debug)
- fprintf_unfiltered (gdb_stdlog, "arg %d @ sp + %d\n",
- argnum, nstack);
- si = push_stack_item (si, val, INT_REGISTER_SIZE);
- nstack += INT_REGISTER_SIZE;
- }
-
- len -= partial_len;
- val += partial_len;
- }
- }
- /* If we have an odd number of words to push, then decrement the stack
- by one word now, so first stack argument will be dword aligned. */
- if (nstack & 4)
- sp -= 4;
+ /* If we restore SP from a register, assume this was the frame register.
+ Otherwise just fall back to SP as frame register. */
+ if (trad_frame_realreg_p (cache->saved_regs, ARM_SP_REGNUM))
+ cache->framereg = cache->saved_regs[ARM_SP_REGNUM].realreg;
+ else
+ cache->framereg = ARM_SP_REGNUM;
- while (si)
- {
- sp -= si->len;
- write_memory (sp, si->data, si->len);
- si = pop_stack_item (si);
- }
+ /* Determine offset to previous frame. */
+ cache->framesize
+ = vsp - get_frame_register_unsigned (this_frame, cache->framereg);
- /* Finally, update teh SP register. */
- regcache_cooked_write_unsigned (regcache, ARM_SP_REGNUM, sp);
+ /* We already got the previous SP. */
+ cache->prev_sp = vsp;
- return sp;
+ return cache;
}
+/* Unwinding via ARM exception table entries. Note that the sniffer
+ already computes a filled-in prologue cache, which is then used
+ with the same arm_prologue_this_id and arm_prologue_prev_register
+ routines also used for prologue-parsing based unwinding. */
-/* Always align the frame to an 8-byte boundary. This is required on
- some platforms and harmless on the rest. */
-
-static CORE_ADDR
-arm_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
+static int
+arm_exidx_unwind_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_prologue_cache)
{
- /* Align the stack to eight bytes. */
- return sp & ~ (CORE_ADDR) 7;
-}
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ CORE_ADDR addr_in_block, exidx_region, func_start;
+ struct arm_prologue_cache *cache;
+ gdb_byte *entry;
-static void
-print_fpu_flags (int flags)
-{
- if (flags & (1 << 0))
- fputs ("IVO ", stdout);
- if (flags & (1 << 1))
- fputs ("DVZ ", stdout);
- if (flags & (1 << 2))
- fputs ("OFL ", stdout);
- if (flags & (1 << 3))
- fputs ("UFL ", stdout);
- if (flags & (1 << 4))
- fputs ("INX ", stdout);
- putchar ('\n');
-}
+ /* See if we have an ARM exception table entry covering this address. */
+ addr_in_block = get_frame_address_in_block (this_frame);
+ entry = arm_find_exidx_entry (addr_in_block, &exidx_region);
+ if (!entry)
+ return 0;
-/* Print interesting information about the floating point processor
- (if present) or emulator. */
-static void
-arm_print_float_info (struct gdbarch *gdbarch, struct ui_file *file,
- struct frame_info *frame, const char *args)
-{
- unsigned long status = get_frame_register_unsigned (frame, ARM_FPS_REGNUM);
- int type;
+ /* The ARM exception table does not describe unwind information
+ for arbitrary PC values, but is guaranteed to be correct only
+ at call sites. We have to decide here whether we want to use
+ ARM exception table information for this frame, or fall back
+ to using prologue parsing. (Note that if we have DWARF CFI,
+ this sniffer isn't even called -- CFI is always preferred.)
+
+ Before we make this decision, however, we check whether we
+ actually have *symbol* information for the current frame.
+ If not, prologue parsing would not work anyway, so we might
+ as well use the exception table and hope for the best. */
+ if (find_pc_partial_function (addr_in_block, NULL, &func_start, NULL))
+ {
+ int exc_valid = 0;
+
+ /* If the next frame is "normal", we are at a call site in this
+ frame, so exception information is guaranteed to be valid. */
+ if (get_next_frame (this_frame)
+ && get_frame_type (get_next_frame (this_frame)) == NORMAL_FRAME)
+ exc_valid = 1;
+
+ /* We also assume exception information is valid if we're currently
+ blocked in a system call. The system library is supposed to
+ ensure this, so that e.g. pthread cancellation works. */
+ if (arm_frame_is_thumb (this_frame))
+ {
+ LONGEST insn;
- type = (status >> 24) & 127;
- if (status & (1 << 31))
- printf (_("Hardware FPU type %d\n"), type);
- else
- printf (_("Software FPU type %d\n"), type);
- /* i18n: [floating point unit] mask */
- fputs (_("mask: "), stdout);
- print_fpu_flags (status >> 16);
- /* i18n: [floating point unit] flags */
- fputs (_("flags: "), stdout);
- print_fpu_flags (status);
-}
+ if (safe_read_memory_integer (get_frame_pc (this_frame) - 2, 2,
+ byte_order_for_code, &insn)
+ && (insn & 0xff00) == 0xdf00 /* svc */)
+ exc_valid = 1;
+ }
+ else
+ {
+ LONGEST insn;
-/* Construct the ARM extended floating point type. */
-static struct type *
-arm_ext_type (struct gdbarch *gdbarch)
-{
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ if (safe_read_memory_integer (get_frame_pc (this_frame) - 4, 4,
+ byte_order_for_code, &insn)
+ && (insn & 0x0f000000) == 0x0f000000 /* svc */)
+ exc_valid = 1;
+ }
+
+ /* Bail out if we don't know that exception information is valid. */
+ if (!exc_valid)
+ return 0;
- if (!tdep->arm_ext_type)
- tdep->arm_ext_type
- = arch_float_type (gdbarch, -1, "builtin_type_arm_ext",
- floatformats_arm_ext);
+ /* The ARM exception index does not mark the *end* of the region
+ covered by the entry, and some functions will not have any entry.
+ To correctly recognize the end of the covered region, the linker
+ should have inserted dummy records with a CANTUNWIND marker.
+
+ Unfortunately, current versions of GNU ld do not reliably do
+ this, and thus we may have found an incorrect entry above.
+ As a (temporary) sanity check, we only use the entry if it
+ lies *within* the bounds of the function. Note that this check
+ might reject perfectly valid entries that just happen to cover
+ multiple functions; therefore this check ought to be removed
+ once the linker is fixed. */
+ if (func_start > exidx_region)
+ return 0;
+ }
- return tdep->arm_ext_type;
+ /* Decode the list of unwinding instructions into a prologue cache.
+ Note that this may fail due to e.g. a "refuse to unwind" code. */
+ cache = arm_exidx_fill_cache (this_frame, entry);
+ if (!cache)
+ return 0;
+
+ *this_prologue_cache = cache;
+ return 1;
}
-static struct type *
-arm_neon_double_type (struct gdbarch *gdbarch)
-{
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+struct frame_unwind arm_exidx_unwind = {
+ NORMAL_FRAME,
+ default_frame_unwind_stop_reason,
+ arm_prologue_this_id,
+ arm_prologue_prev_register,
+ NULL,
+ arm_exidx_unwind_sniffer
+};
- if (tdep->neon_double_type == NULL)
- {
- struct type *t, *elem;
+static struct arm_prologue_cache *
+arm_make_stub_cache (struct frame_info *this_frame)
+{
+ struct arm_prologue_cache *cache;
- t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_d",
- TYPE_CODE_UNION);
- elem = builtin_type (gdbarch)->builtin_uint8;
- append_composite_type_field (t, "u8", init_vector_type (elem, 8));
- elem = builtin_type (gdbarch)->builtin_uint16;
- append_composite_type_field (t, "u16", init_vector_type (elem, 4));
- elem = builtin_type (gdbarch)->builtin_uint32;
- append_composite_type_field (t, "u32", init_vector_type (elem, 2));
- elem = builtin_type (gdbarch)->builtin_uint64;
- append_composite_type_field (t, "u64", elem);
- elem = builtin_type (gdbarch)->builtin_float;
- append_composite_type_field (t, "f32", init_vector_type (elem, 2));
- elem = builtin_type (gdbarch)->builtin_double;
- append_composite_type_field (t, "f64", elem);
+ cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache);
+ cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
- TYPE_VECTOR (t) = 1;
- TYPE_NAME (t) = "neon_d";
- tdep->neon_double_type = t;
- }
+ cache->prev_sp = get_frame_register_unsigned (this_frame, ARM_SP_REGNUM);
- return tdep->neon_double_type;
+ return cache;
}
-/* FIXME: The vector types are not correctly ordered on big-endian
- targets. Just as s0 is the low bits of d0, d0[0] is also the low
- bits of d0 - regardless of what unit size is being held in d0. So
- the offset of the first uint8 in d0 is 7, but the offset of the
- first float is 4. This code works as-is for little-endian
- targets. */
+/* Our frame ID for a stub frame is the current SP and LR. */
-static struct type *
-arm_neon_quad_type (struct gdbarch *gdbarch)
+static void
+arm_stub_this_id (struct frame_info *this_frame,
+ void **this_cache,
+ struct frame_id *this_id)
{
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ struct arm_prologue_cache *cache;
- if (tdep->neon_quad_type == NULL)
- {
- struct type *t, *elem;
+ if (*this_cache == NULL)
+ *this_cache = arm_make_stub_cache (this_frame);
+ cache = *this_cache;
- t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_q",
- TYPE_CODE_UNION);
- elem = builtin_type (gdbarch)->builtin_uint8;
- append_composite_type_field (t, "u8", init_vector_type (elem, 16));
- elem = builtin_type (gdbarch)->builtin_uint16;
- append_composite_type_field (t, "u16", init_vector_type (elem, 8));
- elem = builtin_type (gdbarch)->builtin_uint32;
- append_composite_type_field (t, "u32", init_vector_type (elem, 4));
- elem = builtin_type (gdbarch)->builtin_uint64;
- append_composite_type_field (t, "u64", init_vector_type (elem, 2));
- elem = builtin_type (gdbarch)->builtin_float;
- append_composite_type_field (t, "f32", init_vector_type (elem, 4));
- elem = builtin_type (gdbarch)->builtin_double;
- append_composite_type_field (t, "f64", init_vector_type (elem, 2));
+ *this_id = frame_id_build (cache->prev_sp, get_frame_pc (this_frame));
+}
- TYPE_VECTOR (t) = 1;
- TYPE_NAME (t) = "neon_q";
- tdep->neon_quad_type = t;
- }
+static int
+arm_stub_unwind_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_prologue_cache)
+{
+ CORE_ADDR addr_in_block;
+ char dummy[4];
- return tdep->neon_quad_type;
+ addr_in_block = get_frame_address_in_block (this_frame);
+ if (in_plt_section (addr_in_block, NULL)
+ /* We also use the stub winder if the target memory is unreadable
+ to avoid having the prologue unwinder trying to read it. */
+ || target_read_memory (get_frame_pc (this_frame), dummy, 4) != 0)
+ return 1;
+
+ return 0;
}
-/* Return the GDB type object for the "standard" data type of data in
- register N. */
+struct frame_unwind arm_stub_unwind = {
+ NORMAL_FRAME,
+ default_frame_unwind_stop_reason,
+ arm_stub_this_id,
+ arm_prologue_prev_register,
+ NULL,
+ arm_stub_unwind_sniffer
+};
-static struct type *
-arm_register_type (struct gdbarch *gdbarch, int regnum)
+static CORE_ADDR
+arm_normal_frame_base (struct frame_info *this_frame, void **this_cache)
{
- int num_regs = gdbarch_num_regs (gdbarch);
-
- if (gdbarch_tdep (gdbarch)->have_vfp_pseudos
- && regnum >= num_regs && regnum < num_regs + 32)
- return builtin_type (gdbarch)->builtin_float;
+ struct arm_prologue_cache *cache;
- if (gdbarch_tdep (gdbarch)->have_neon_pseudos
- && regnum >= num_regs + 32 && regnum < num_regs + 32 + 16)
- return arm_neon_quad_type (gdbarch);
+ if (*this_cache == NULL)
+ *this_cache = arm_make_prologue_cache (this_frame);
+ cache = *this_cache;
- /* If the target description has register information, we are only
- in this function so that we can override the types of
- double-precision registers for NEON. */
- if (tdesc_has_registers (gdbarch_target_desc (gdbarch)))
- {
- struct type *t = tdesc_register_type (gdbarch, regnum);
+ return cache->prev_sp - cache->framesize;
+}
- if (regnum >= ARM_D0_REGNUM && regnum < ARM_D0_REGNUM + 32
- && TYPE_CODE (t) == TYPE_CODE_FLT
- && gdbarch_tdep (gdbarch)->have_neon)
- return arm_neon_double_type (gdbarch);
- else
- return t;
- }
+struct frame_base arm_normal_base = {
+ &arm_prologue_unwind,
+ arm_normal_frame_base,
+ arm_normal_frame_base,
+ arm_normal_frame_base
+};
- if (regnum >= ARM_F0_REGNUM && regnum < ARM_F0_REGNUM + NUM_FREGS)
- {
- if (!gdbarch_tdep (gdbarch)->have_fpa_registers)
- return builtin_type (gdbarch)->builtin_void;
+/* Assuming THIS_FRAME is a dummy, return the frame ID of that
+ dummy frame. The frame ID's base needs to match the TOS value
+ saved by save_dummy_frame_tos() and returned from
+ arm_push_dummy_call, and the PC needs to match the dummy frame's
+ breakpoint. */
- return arm_ext_type (gdbarch);
+static struct frame_id
+arm_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
+{
+ return frame_id_build (get_frame_register_unsigned (this_frame,
+ ARM_SP_REGNUM),
+ get_frame_pc (this_frame));
+}
+
+/* Given THIS_FRAME, find the previous frame's resume PC (which will
+ be used to construct the previous frame's ID, after looking up the
+ containing function). */
+
+static CORE_ADDR
+arm_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame)
+{
+ CORE_ADDR pc;
+ pc = frame_unwind_register_unsigned (this_frame, ARM_PC_REGNUM);
+ return arm_addr_bits_remove (gdbarch, pc);
+}
+
+static CORE_ADDR
+arm_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
+{
+ return frame_unwind_register_unsigned (this_frame, ARM_SP_REGNUM);
+}
+
+static struct value *
+arm_dwarf2_prev_register (struct frame_info *this_frame, void **this_cache,
+ int regnum)
+{
+ struct gdbarch * gdbarch = get_frame_arch (this_frame);
+ CORE_ADDR lr, cpsr;
+ ULONGEST t_bit = arm_psr_thumb_bit (gdbarch);
+
+ switch (regnum)
+ {
+ case ARM_PC_REGNUM:
+ /* The PC is normally copied from the return column, which
+ describes saves of LR. However, that version may have an
+ extra bit set to indicate Thumb state. The bit is not
+ part of the PC. */
+ lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
+ return frame_unwind_got_constant (this_frame, regnum,
+ arm_addr_bits_remove (gdbarch, lr));
+
+ case ARM_PS_REGNUM:
+ /* Reconstruct the T bit; see arm_prologue_prev_register for details. */
+ cpsr = get_frame_register_unsigned (this_frame, regnum);
+ lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
+ if (IS_THUMB_ADDR (lr))
+ cpsr |= t_bit;
+ else
+ cpsr &= ~t_bit;
+ return frame_unwind_got_constant (this_frame, regnum, cpsr);
+
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("Unexpected register %d"), regnum);
}
- else if (regnum == ARM_SP_REGNUM)
- return builtin_type (gdbarch)->builtin_data_ptr;
- else if (regnum == ARM_PC_REGNUM)
- return builtin_type (gdbarch)->builtin_func_ptr;
- else if (regnum >= ARRAY_SIZE (arm_register_names))
- /* These registers are only supported on targets which supply
- an XML description. */
- return builtin_type (gdbarch)->builtin_int0;
- else
- return builtin_type (gdbarch)->builtin_uint32;
}
-/* Map a DWARF register REGNUM onto the appropriate GDB register
- number. */
+static void
+arm_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
+ struct dwarf2_frame_state_reg *reg,
+ struct frame_info *this_frame)
+{
+ switch (regnum)
+ {
+ case ARM_PC_REGNUM:
+ case ARM_PS_REGNUM:
+ reg->how = DWARF2_FRAME_REG_FN;
+ reg->loc.fn = arm_dwarf2_prev_register;
+ break;
+ case ARM_SP_REGNUM:
+ reg->how = DWARF2_FRAME_REG_CFA;
+ break;
+ }
+}
+
+/* Return true if we are in the function's epilogue, i.e. after the
+ instruction that destroyed the function's stack frame. */
static int
-arm_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg)
+thumb_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
{
- /* Core integer regs. */
- if (reg >= 0 && reg <= 15)
- return reg;
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned int insn, insn2;
+ int found_return = 0, found_stack_adjust = 0;
+ CORE_ADDR func_start, func_end;
+ CORE_ADDR scan_pc;
+ gdb_byte buf[4];
- /* Legacy FPA encoding. These were once used in a way which
- overlapped with VFP register numbering, so their use is
- discouraged, but GDB doesn't support the ARM toolchain
- which used them for VFP. */
- if (reg >= 16 && reg <= 23)
- return ARM_F0_REGNUM + reg - 16;
+ if (!find_pc_partial_function (pc, NULL, &func_start, &func_end))
+ return 0;
- /* New assignments for the FPA registers. */
- if (reg >= 96 && reg <= 103)
- return ARM_F0_REGNUM + reg - 96;
+ /* The epilogue is a sequence of instructions along the following lines:
- /* WMMX register assignments. */
- if (reg >= 104 && reg <= 111)
- return ARM_WCGR0_REGNUM + reg - 104;
+ - add stack frame size to SP or FP
+ - [if frame pointer used] restore SP from FP
+ - restore registers from SP [may include PC]
+ - a return-type instruction [if PC wasn't already restored]
- if (reg >= 112 && reg <= 127)
- return ARM_WR0_REGNUM + reg - 112;
+ In a first pass, we scan forward from the current PC and verify the
+ instructions we find as compatible with this sequence, ending in a
+ return instruction.
- if (reg >= 192 && reg <= 199)
- return ARM_WC0_REGNUM + reg - 192;
+ However, this is not sufficient to distinguish indirect function calls
+ within a function from indirect tail calls in the epilogue in some cases.
+ Therefore, if we didn't already find any SP-changing instruction during
+ forward scan, we add a backward scanning heuristic to ensure we actually
+ are in the epilogue. */
- /* VFP v2 registers. A double precision value is actually
- in d1 rather than s2, but the ABI only defines numbering
- for the single precision registers. This will "just work"
- in GDB for little endian targets (we'll read eight bytes,
- starting in s0 and then progressing to s1), but will be
- reversed on big endian targets with VFP. This won't
- be a problem for the new Neon quad registers; you're supposed
- to use DW_OP_piece for those. */
- if (reg >= 64 && reg <= 95)
+ scan_pc = pc;
+ while (scan_pc < func_end && !found_return)
{
- char name_buf[4];
+ if (target_read_memory (scan_pc, buf, 2))
+ break;
- sprintf (name_buf, "s%d", reg - 64);
- return user_reg_map_name_to_regnum (gdbarch, name_buf,
- strlen (name_buf));
+ scan_pc += 2;
+ insn = extract_unsigned_integer (buf, 2, byte_order_for_code);
+
+ if ((insn & 0xff80) == 0x4700) /* bx <Rm> */
+ found_return = 1;
+ else if (insn == 0x46f7) /* mov pc, lr */
+ found_return = 1;
+ else if (insn == 0x46bd) /* mov sp, r7 */
+ found_stack_adjust = 1;
+ else if ((insn & 0xff00) == 0xb000) /* add sp, imm or sub sp, imm */
+ found_stack_adjust = 1;
+ else if ((insn & 0xfe00) == 0xbc00) /* pop <registers> */
+ {
+ found_stack_adjust = 1;
+ if (insn & 0x0100) /* <registers> include PC. */
+ found_return = 1;
+ }
+ else if (thumb_insn_size (insn) == 4) /* 32-bit Thumb-2 instruction */
+ {
+ if (target_read_memory (scan_pc, buf, 2))
+ break;
+
+ scan_pc += 2;
+ insn2 = extract_unsigned_integer (buf, 2, byte_order_for_code);
+
+ if (insn == 0xe8bd) /* ldm.w sp!, <registers> */
+ {
+ found_stack_adjust = 1;
+ if (insn2 & 0x8000) /* <registers> include PC. */
+ found_return = 1;
+ }
+ else if (insn == 0xf85d /* ldr.w <Rt>, [sp], #4 */
+ && (insn2 & 0x0fff) == 0x0b04)
+ {
+ found_stack_adjust = 1;
+ if ((insn2 & 0xf000) == 0xf000) /* <Rt> is PC. */
+ found_return = 1;
+ }
+ else if ((insn & 0xffbf) == 0xecbd /* vldm sp!, <list> */
+ && (insn2 & 0x0e00) == 0x0a00)
+ found_stack_adjust = 1;
+ else
+ break;
+ }
+ else
+ break;
}
- /* VFP v3 / Neon registers. This range is also used for VFP v2
- registers, except that it now describes d0 instead of s0. */
- if (reg >= 256 && reg <= 287)
+ if (!found_return)
+ return 0;
+
+ /* Since any instruction in the epilogue sequence, with the possible
+ exception of return itself, updates the stack pointer, we need to
+ scan backwards for at most one instruction. Try either a 16-bit or
+ a 32-bit instruction. This is just a heuristic, so we do not worry
+ too much about false positives. */
+
+ if (!found_stack_adjust)
{
- char name_buf[4];
+ if (pc - 4 < func_start)
+ return 0;
+ if (target_read_memory (pc - 4, buf, 4))
+ return 0;
- sprintf (name_buf, "d%d", reg - 256);
- return user_reg_map_name_to_regnum (gdbarch, name_buf,
- strlen (name_buf));
+ insn = extract_unsigned_integer (buf, 2, byte_order_for_code);
+ insn2 = extract_unsigned_integer (buf + 2, 2, byte_order_for_code);
+
+ if (insn2 == 0x46bd) /* mov sp, r7 */
+ found_stack_adjust = 1;
+ else if ((insn2 & 0xff00) == 0xb000) /* add sp, imm or sub sp, imm */
+ found_stack_adjust = 1;
+ else if ((insn2 & 0xff00) == 0xbc00) /* pop <registers> without PC */
+ found_stack_adjust = 1;
+ else if (insn == 0xe8bd) /* ldm.w sp!, <registers> */
+ found_stack_adjust = 1;
+ else if (insn == 0xf85d /* ldr.w <Rt>, [sp], #4 */
+ && (insn2 & 0x0fff) == 0x0b04)
+ found_stack_adjust = 1;
+ else if ((insn & 0xffbf) == 0xecbd /* vldm sp!, <list> */
+ && (insn2 & 0x0e00) == 0x0a00)
+ found_stack_adjust = 1;
}
- return -1;
+ return found_stack_adjust;
}
-/* Map GDB internal REGNUM onto the Arm simulator register numbers. */
+/* Return true if we are in the function's epilogue, i.e. after the
+ instruction that destroyed the function's stack frame. */
+
static int
-arm_register_sim_regno (struct gdbarch *gdbarch, int regnum)
+arm_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
{
- int reg = regnum;
- gdb_assert (reg >= 0 && reg < gdbarch_num_regs (gdbarch));
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned int insn;
+ int found_return, found_stack_adjust;
+ CORE_ADDR func_start, func_end;
- if (regnum >= ARM_WR0_REGNUM && regnum <= ARM_WR15_REGNUM)
- return regnum - ARM_WR0_REGNUM + SIM_ARM_IWMMXT_COP0R0_REGNUM;
+ if (arm_pc_is_thumb (gdbarch, pc))
+ return thumb_in_function_epilogue_p (gdbarch, pc);
- if (regnum >= ARM_WC0_REGNUM && regnum <= ARM_WC7_REGNUM)
- return regnum - ARM_WC0_REGNUM + SIM_ARM_IWMMXT_COP1R0_REGNUM;
+ if (!find_pc_partial_function (pc, NULL, &func_start, &func_end))
+ return 0;
- if (regnum >= ARM_WCGR0_REGNUM && regnum <= ARM_WCGR7_REGNUM)
- return regnum - ARM_WCGR0_REGNUM + SIM_ARM_IWMMXT_COP1R8_REGNUM;
+ /* We are in the epilogue if the previous instruction was a stack
+ adjustment and the next instruction is a possible return (bx, mov
+ pc, or pop). We could have to scan backwards to find the stack
+ adjustment, or forwards to find the return, but this is a decent
+ approximation. First scan forwards. */
- if (reg < NUM_GREGS)
- return SIM_ARM_R0_REGNUM + reg;
- reg -= NUM_GREGS;
+ found_return = 0;
+ insn = read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+ if (bits (insn, 28, 31) != INST_NV)
+ {
+ if ((insn & 0x0ffffff0) == 0x012fff10)
+ /* BX. */
+ found_return = 1;
+ else if ((insn & 0x0ffffff0) == 0x01a0f000)
+ /* MOV PC. */
+ found_return = 1;
+ else if ((insn & 0x0fff0000) == 0x08bd0000
+ && (insn & 0x0000c000) != 0)
+ /* POP (LDMIA), including PC or LR. */
+ found_return = 1;
+ }
- if (reg < NUM_FREGS)
- return SIM_ARM_FP0_REGNUM + reg;
- reg -= NUM_FREGS;
+ if (!found_return)
+ return 0;
- if (reg < NUM_SREGS)
- return SIM_ARM_FPS_REGNUM + reg;
- reg -= NUM_SREGS;
+ /* Scan backwards. This is just a heuristic, so do not worry about
+ false positives from mode changes. */
- internal_error (__FILE__, __LINE__, _("Bad REGNUM %d"), regnum);
+ if (pc < func_start + 4)
+ return 0;
+
+ found_stack_adjust = 0;
+ insn = read_memory_unsigned_integer (pc - 4, 4, byte_order_for_code);
+ if (bits (insn, 28, 31) != INST_NV)
+ {
+ if ((insn & 0x0df0f000) == 0x0080d000)
+ /* ADD SP (register or immediate). */
+ found_stack_adjust = 1;
+ else if ((insn & 0x0df0f000) == 0x0040d000)
+ /* SUB SP (register or immediate). */
+ found_stack_adjust = 1;
+ else if ((insn & 0x0ffffff0) == 0x01a0d000)
+ /* MOV SP. */
+ found_stack_adjust = 1;
+ else if ((insn & 0x0fff0000) == 0x08bd0000)
+ /* POP (LDMIA). */
+ found_stack_adjust = 1;
+ }
+
+ if (found_stack_adjust)
+ return 1;
+
+ return 0;
}
-/* NOTE: cagney/2001-08-20: Both convert_from_extended() and
- convert_to_extended() use floatformat_arm_ext_littlebyte_bigword.
- It is thought that this is is the floating-point register format on
- little-endian systems. */
-static void
-convert_from_extended (const struct floatformat *fmt, const void *ptr,
- void *dbl, int endianess)
+/* When arguments must be pushed onto the stack, they go on in reverse
+ order. The code below implements a FILO (stack) to do this. */
+
+struct stack_item
{
- DOUBLEST d;
+ int len;
+ struct stack_item *prev;
+ void *data;
+};
- if (endianess == BFD_ENDIAN_BIG)
- floatformat_to_doublest (&floatformat_arm_ext_big, ptr, &d);
- else
- floatformat_to_doublest (&floatformat_arm_ext_littlebyte_bigword,
- ptr, &d);
- floatformat_from_doublest (fmt, &d, dbl);
+static struct stack_item *
+push_stack_item (struct stack_item *prev, const void *contents, int len)
+{
+ struct stack_item *si;
+ si = xmalloc (sizeof (struct stack_item));
+ si->data = xmalloc (len);
+ si->len = len;
+ si->prev = prev;
+ memcpy (si->data, contents, len);
+ return si;
}
-static void
-convert_to_extended (const struct floatformat *fmt, void *dbl, const void *ptr,
- int endianess)
+static struct stack_item *
+pop_stack_item (struct stack_item *si)
{
- DOUBLEST d;
-
- floatformat_to_doublest (fmt, ptr, &d);
- if (endianess == BFD_ENDIAN_BIG)
- floatformat_from_doublest (&floatformat_arm_ext_big, &d, dbl);
- else
- floatformat_from_doublest (&floatformat_arm_ext_littlebyte_bigword,
- &d, dbl);
+ struct stack_item *dead = si;
+ si = si->prev;
+ xfree (dead->data);
+ xfree (dead);
+ return si;
}
+
+/* Return the alignment (in bytes) of the given type. */
+
static int
-condition_true (unsigned long cond, unsigned long status_reg)
+arm_type_align (struct type *t)
{
- if (cond == INST_AL || cond == INST_NV)
- return 1;
+ int n;
+ int align;
+ int falign;
- switch (cond)
+ t = check_typedef (t);
+ switch (TYPE_CODE (t))
{
- case INST_EQ:
- return ((status_reg & FLAG_Z) != 0);
- case INST_NE:
- return ((status_reg & FLAG_Z) == 0);
- case INST_CS:
+ default:
+ /* Should never happen. */
+ internal_error (__FILE__, __LINE__, _("unknown type alignment"));
+ return 4;
+
+ case TYPE_CODE_PTR:
+ case TYPE_CODE_ENUM:
+ case TYPE_CODE_INT:
+ case TYPE_CODE_FLT:
+ case TYPE_CODE_SET:
+ case TYPE_CODE_RANGE:
+ case TYPE_CODE_BITSTRING:
+ case TYPE_CODE_REF:
+ case TYPE_CODE_CHAR:
+ case TYPE_CODE_BOOL:
+ return TYPE_LENGTH (t);
+
+ case TYPE_CODE_ARRAY:
+ case TYPE_CODE_COMPLEX:
+ /* TODO: What about vector types? */
+ return arm_type_align (TYPE_TARGET_TYPE (t));
+
+ case TYPE_CODE_STRUCT:
+ case TYPE_CODE_UNION:
+ align = 1;
+ for (n = 0; n < TYPE_NFIELDS (t); n++)
+ {
+ falign = arm_type_align (TYPE_FIELD_TYPE (t, n));
+ if (falign > align)
+ align = falign;
+ }
+ return align;
+ }
+}
+
+/* Possible base types for a candidate for passing and returning in
+ VFP registers. */
+
+enum arm_vfp_cprc_base_type
+{
+ VFP_CPRC_UNKNOWN,
+ VFP_CPRC_SINGLE,
+ VFP_CPRC_DOUBLE,
+ VFP_CPRC_VEC64,
+ VFP_CPRC_VEC128
+};
+
+/* The length of one element of base type B. */
+
+static unsigned
+arm_vfp_cprc_unit_length (enum arm_vfp_cprc_base_type b)
+{
+ switch (b)
+ {
+ case VFP_CPRC_SINGLE:
+ return 4;
+ case VFP_CPRC_DOUBLE:
+ return 8;
+ case VFP_CPRC_VEC64:
+ return 8;
+ case VFP_CPRC_VEC128:
+ return 16;
+ default:
+ internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."),
+ (int) b);
+ }
+}
+
+/* The character ('s', 'd' or 'q') for the type of VFP register used
+ for passing base type B. */
+
+static int
+arm_vfp_cprc_reg_char (enum arm_vfp_cprc_base_type b)
+{
+ switch (b)
+ {
+ case VFP_CPRC_SINGLE:
+ return 's';
+ case VFP_CPRC_DOUBLE:
+ return 'd';
+ case VFP_CPRC_VEC64:
+ return 'd';
+ case VFP_CPRC_VEC128:
+ return 'q';
+ default:
+ internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."),
+ (int) b);
+ }
+}
+
+/* Determine whether T may be part of a candidate for passing and
+ returning in VFP registers, ignoring the limit on the total number
+ of components. If *BASE_TYPE is VFP_CPRC_UNKNOWN, set it to the
+ classification of the first valid component found; if it is not
+ VFP_CPRC_UNKNOWN, all components must have the same classification
+ as *BASE_TYPE. If it is found that T contains a type not permitted
+ for passing and returning in VFP registers, a type differently
+ classified from *BASE_TYPE, or two types differently classified
+ from each other, return -1, otherwise return the total number of
+ base-type elements found (possibly 0 in an empty structure or
+ array). Vectors and complex types are not currently supported,
+ matching the generic AAPCS support. */
+
+static int
+arm_vfp_cprc_sub_candidate (struct type *t,
+ enum arm_vfp_cprc_base_type *base_type)
+{
+ t = check_typedef (t);
+ switch (TYPE_CODE (t))
+ {
+ case TYPE_CODE_FLT:
+ switch (TYPE_LENGTH (t))
+ {
+ case 4:
+ if (*base_type == VFP_CPRC_UNKNOWN)
+ *base_type = VFP_CPRC_SINGLE;
+ else if (*base_type != VFP_CPRC_SINGLE)
+ return -1;
+ return 1;
+
+ case 8:
+ if (*base_type == VFP_CPRC_UNKNOWN)
+ *base_type = VFP_CPRC_DOUBLE;
+ else if (*base_type != VFP_CPRC_DOUBLE)
+ return -1;
+ return 1;
+
+ default:
+ return -1;
+ }
+ break;
+
+ case TYPE_CODE_ARRAY:
+ {
+ int count;
+ unsigned unitlen;
+ count = arm_vfp_cprc_sub_candidate (TYPE_TARGET_TYPE (t), base_type);
+ if (count == -1)
+ return -1;
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ gdb_assert ((TYPE_LENGTH (t) % unitlen) == 0);
+ return TYPE_LENGTH (t) / unitlen;
+ }
+ break;
+
+ case TYPE_CODE_STRUCT:
+ {
+ int count = 0;
+ unsigned unitlen;
+ int i;
+ for (i = 0; i < TYPE_NFIELDS (t); i++)
+ {
+ int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i),
+ base_type);
+ if (sub_count == -1)
+ return -1;
+ count += sub_count;
+ }
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ if (TYPE_LENGTH (t) != unitlen * count)
+ return -1;
+ return count;
+ }
+
+ case TYPE_CODE_UNION:
+ {
+ int count = 0;
+ unsigned unitlen;
+ int i;
+ for (i = 0; i < TYPE_NFIELDS (t); i++)
+ {
+ int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i),
+ base_type);
+ if (sub_count == -1)
+ return -1;
+ count = (count > sub_count ? count : sub_count);
+ }
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ if (TYPE_LENGTH (t) != unitlen * count)
+ return -1;
+ return count;
+ }
+
+ default:
+ break;
+ }
+
+ return -1;
+}
+
+/* Determine whether T is a VFP co-processor register candidate (CPRC)
+ if passed to or returned from a non-variadic function with the VFP
+ ABI in effect. Return 1 if it is, 0 otherwise. If it is, set
+ *BASE_TYPE to the base type for T and *COUNT to the number of
+ elements of that base type before returning. */
+
+static int
+arm_vfp_call_candidate (struct type *t, enum arm_vfp_cprc_base_type *base_type,
+ int *count)
+{
+ enum arm_vfp_cprc_base_type b = VFP_CPRC_UNKNOWN;
+ int c = arm_vfp_cprc_sub_candidate (t, &b);
+ if (c <= 0 || c > 4)
+ return 0;
+ *base_type = b;
+ *count = c;
+ return 1;
+}
+
+/* Return 1 if the VFP ABI should be used for passing arguments to and
+ returning values from a function of type FUNC_TYPE, 0
+ otherwise. */
+
+static int
+arm_vfp_abi_for_function (struct gdbarch *gdbarch, struct type *func_type)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ /* Variadic functions always use the base ABI. Assume that functions
+ without debug info are not variadic. */
+ if (func_type && TYPE_VARARGS (check_typedef (func_type)))
+ return 0;
+ /* The VFP ABI is only supported as a variant of AAPCS. */
+ if (tdep->arm_abi != ARM_ABI_AAPCS)
+ return 0;
+ return gdbarch_tdep (gdbarch)->fp_model == ARM_FLOAT_VFP;
+}
+
+/* We currently only support passing parameters in integer registers, which
+ conforms with GCC's default model, and VFP argument passing following
+ the VFP variant of AAPCS. Several other variants exist and
+ we should probably support some of them based on the selected ABI. */
+
+static CORE_ADDR
+arm_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
+ struct regcache *regcache, CORE_ADDR bp_addr, int nargs,
+ struct value **args, CORE_ADDR sp, int struct_return,
+ CORE_ADDR struct_addr)
+{
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int argnum;
+ int argreg;
+ int nstack;
+ struct stack_item *si = NULL;
+ int use_vfp_abi;
+ struct type *ftype;
+ unsigned vfp_regs_free = (1 << 16) - 1;
+
+ /* Determine the type of this function and whether the VFP ABI
+ applies. */
+ ftype = check_typedef (value_type (function));
+ if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
+ ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
+ use_vfp_abi = arm_vfp_abi_for_function (gdbarch, ftype);
+
+ /* Set the return address. For the ARM, the return breakpoint is
+ always at BP_ADDR. */
+ if (arm_pc_is_thumb (gdbarch, bp_addr))
+ bp_addr |= 1;
+ regcache_cooked_write_unsigned (regcache, ARM_LR_REGNUM, bp_addr);
+
+ /* Walk through the list of args and determine how large a temporary
+ stack is required. Need to take care here as structs may be
+ passed on the stack, and we have to push them. */
+ nstack = 0;
+
+ argreg = ARM_A1_REGNUM;
+ nstack = 0;
+
+ /* The struct_return pointer occupies the first parameter
+ passing register. */
+ if (struct_return)
+ {
+ if (arm_debug)
+ fprintf_unfiltered (gdb_stdlog, "struct return in %s = %s\n",
+ gdbarch_register_name (gdbarch, argreg),
+ paddress (gdbarch, struct_addr));
+ regcache_cooked_write_unsigned (regcache, argreg, struct_addr);
+ argreg++;
+ }
+
+ for (argnum = 0; argnum < nargs; argnum++)
+ {
+ int len;
+ struct type *arg_type;
+ struct type *target_type;
+ enum type_code typecode;
+ const bfd_byte *val;
+ int align;
+ enum arm_vfp_cprc_base_type vfp_base_type;
+ int vfp_base_count;
+ int may_use_core_reg = 1;
+
+ arg_type = check_typedef (value_type (args[argnum]));
+ len = TYPE_LENGTH (arg_type);
+ target_type = TYPE_TARGET_TYPE (arg_type);
+ typecode = TYPE_CODE (arg_type);
+ val = value_contents (args[argnum]);
+
+ align = arm_type_align (arg_type);
+ /* Round alignment up to a whole number of words. */
+ align = (align + INT_REGISTER_SIZE - 1) & ~(INT_REGISTER_SIZE - 1);
+ /* Different ABIs have different maximum alignments. */
+ if (gdbarch_tdep (gdbarch)->arm_abi == ARM_ABI_APCS)
+ {
+ /* The APCS ABI only requires word alignment. */
+ align = INT_REGISTER_SIZE;
+ }
+ else
+ {
+ /* The AAPCS requires at most doubleword alignment. */
+ if (align > INT_REGISTER_SIZE * 2)
+ align = INT_REGISTER_SIZE * 2;
+ }
+
+ if (use_vfp_abi
+ && arm_vfp_call_candidate (arg_type, &vfp_base_type,
+ &vfp_base_count))
+ {
+ int regno;
+ int unit_length;
+ int shift;
+ unsigned mask;
+
+ /* Because this is a CPRC it cannot go in a core register or
+ cause a core register to be skipped for alignment.
+ Either it goes in VFP registers and the rest of this loop
+ iteration is skipped for this argument, or it goes on the
+ stack (and the stack alignment code is correct for this
+ case). */
+ may_use_core_reg = 0;
+
+ unit_length = arm_vfp_cprc_unit_length (vfp_base_type);
+ shift = unit_length / 4;
+ mask = (1 << (shift * vfp_base_count)) - 1;
+ for (regno = 0; regno < 16; regno += shift)
+ if (((vfp_regs_free >> regno) & mask) == mask)
+ break;
+
+ if (regno < 16)
+ {
+ int reg_char;
+ int reg_scaled;
+ int i;
+
+ vfp_regs_free &= ~(mask << regno);
+ reg_scaled = regno / shift;
+ reg_char = arm_vfp_cprc_reg_char (vfp_base_type);
+ for (i = 0; i < vfp_base_count; i++)
+ {
+ char name_buf[4];
+ int regnum;
+ if (reg_char == 'q')
+ arm_neon_quad_write (gdbarch, regcache, reg_scaled + i,
+ val + i * unit_length);
+ else
+ {
+ sprintf (name_buf, "%c%d", reg_char, reg_scaled + i);
+ regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ regcache_cooked_write (regcache, regnum,
+ val + i * unit_length);
+ }
+ }
+ continue;
+ }
+ else
+ {
+ /* This CPRC could not go in VFP registers, so all VFP
+ registers are now marked as used. */
+ vfp_regs_free = 0;
+ }
+ }
+
+ /* Push stack padding for dowubleword alignment. */
+ if (nstack & (align - 1))
+ {
+ si = push_stack_item (si, val, INT_REGISTER_SIZE);
+ nstack += INT_REGISTER_SIZE;
+ }
+
+ /* Doubleword aligned quantities must go in even register pairs. */
+ if (may_use_core_reg
+ && argreg <= ARM_LAST_ARG_REGNUM
+ && align > INT_REGISTER_SIZE
+ && argreg & 1)
+ argreg++;
+
+ /* If the argument is a pointer to a function, and it is a
+ Thumb function, create a LOCAL copy of the value and set
+ the THUMB bit in it. */
+ if (TYPE_CODE_PTR == typecode
+ && target_type != NULL
+ && TYPE_CODE_FUNC == TYPE_CODE (check_typedef (target_type)))
+ {
+ CORE_ADDR regval = extract_unsigned_integer (val, len, byte_order);
+ if (arm_pc_is_thumb (gdbarch, regval))
+ {
+ bfd_byte *copy = alloca (len);
+ store_unsigned_integer (copy, len, byte_order,
+ MAKE_THUMB_ADDR (regval));
+ val = copy;
+ }
+ }
+
+ /* Copy the argument to general registers or the stack in
+ register-sized pieces. Large arguments are split between
+ registers and stack. */
+ while (len > 0)
+ {
+ int partial_len = len < INT_REGISTER_SIZE ? len : INT_REGISTER_SIZE;
+
+ if (may_use_core_reg && argreg <= ARM_LAST_ARG_REGNUM)
+ {
+ /* The argument is being passed in a general purpose
+ register. */
+ CORE_ADDR regval
+ = extract_unsigned_integer (val, partial_len, byte_order);
+ if (byte_order == BFD_ENDIAN_BIG)
+ regval <<= (INT_REGISTER_SIZE - partial_len) * 8;
+ if (arm_debug)
+ fprintf_unfiltered (gdb_stdlog, "arg %d in %s = 0x%s\n",
+ argnum,
+ gdbarch_register_name
+ (gdbarch, argreg),
+ phex (regval, INT_REGISTER_SIZE));
+ regcache_cooked_write_unsigned (regcache, argreg, regval);
+ argreg++;
+ }
+ else
+ {
+ /* Push the arguments onto the stack. */
+ if (arm_debug)
+ fprintf_unfiltered (gdb_stdlog, "arg %d @ sp + %d\n",
+ argnum, nstack);
+ si = push_stack_item (si, val, INT_REGISTER_SIZE);
+ nstack += INT_REGISTER_SIZE;
+ }
+
+ len -= partial_len;
+ val += partial_len;
+ }
+ }
+ /* If we have an odd number of words to push, then decrement the stack
+ by one word now, so first stack argument will be dword aligned. */
+ if (nstack & 4)
+ sp -= 4;
+
+ while (si)
+ {
+ sp -= si->len;
+ write_memory (sp, si->data, si->len);
+ si = pop_stack_item (si);
+ }
+
+ /* Finally, update teh SP register. */
+ regcache_cooked_write_unsigned (regcache, ARM_SP_REGNUM, sp);
+
+ return sp;
+}
+
+
+/* Always align the frame to an 8-byte boundary. This is required on
+ some platforms and harmless on the rest. */
+
+static CORE_ADDR
+arm_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
+{
+ /* Align the stack to eight bytes. */
+ return sp & ~ (CORE_ADDR) 7;
+}
+
+static void
+print_fpu_flags (int flags)
+{
+ if (flags & (1 << 0))
+ fputs ("IVO ", stdout);
+ if (flags & (1 << 1))
+ fputs ("DVZ ", stdout);
+ if (flags & (1 << 2))
+ fputs ("OFL ", stdout);
+ if (flags & (1 << 3))
+ fputs ("UFL ", stdout);
+ if (flags & (1 << 4))
+ fputs ("INX ", stdout);
+ putchar ('\n');
+}
+
+/* Print interesting information about the floating point processor
+ (if present) or emulator. */
+static void
+arm_print_float_info (struct gdbarch *gdbarch, struct ui_file *file,
+ struct frame_info *frame, const char *args)
+{
+ unsigned long status = get_frame_register_unsigned (frame, ARM_FPS_REGNUM);
+ int type;
+
+ type = (status >> 24) & 127;
+ if (status & (1 << 31))
+ printf (_("Hardware FPU type %d\n"), type);
+ else
+ printf (_("Software FPU type %d\n"), type);
+ /* i18n: [floating point unit] mask */
+ fputs (_("mask: "), stdout);
+ print_fpu_flags (status >> 16);
+ /* i18n: [floating point unit] flags */
+ fputs (_("flags: "), stdout);
+ print_fpu_flags (status);
+}
+
+/* Construct the ARM extended floating point type. */
+static struct type *
+arm_ext_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (!tdep->arm_ext_type)
+ tdep->arm_ext_type
+ = arch_float_type (gdbarch, -1, "builtin_type_arm_ext",
+ floatformats_arm_ext);
+
+ return tdep->arm_ext_type;
+}
+
+static struct type *
+arm_neon_double_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->neon_double_type == NULL)
+ {
+ struct type *t, *elem;
+
+ t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_d",
+ TYPE_CODE_UNION);
+ elem = builtin_type (gdbarch)->builtin_uint8;
+ append_composite_type_field (t, "u8", init_vector_type (elem, 8));
+ elem = builtin_type (gdbarch)->builtin_uint16;
+ append_composite_type_field (t, "u16", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_uint32;
+ append_composite_type_field (t, "u32", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_uint64;
+ append_composite_type_field (t, "u64", elem);
+ elem = builtin_type (gdbarch)->builtin_float;
+ append_composite_type_field (t, "f32", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_double;
+ append_composite_type_field (t, "f64", elem);
+
+ TYPE_VECTOR (t) = 1;
+ TYPE_NAME (t) = "neon_d";
+ tdep->neon_double_type = t;
+ }
+
+ return tdep->neon_double_type;
+}
+
+/* FIXME: The vector types are not correctly ordered on big-endian
+ targets. Just as s0 is the low bits of d0, d0[0] is also the low
+ bits of d0 - regardless of what unit size is being held in d0. So
+ the offset of the first uint8 in d0 is 7, but the offset of the
+ first float is 4. This code works as-is for little-endian
+ targets. */
+
+static struct type *
+arm_neon_quad_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->neon_quad_type == NULL)
+ {
+ struct type *t, *elem;
+
+ t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_q",
+ TYPE_CODE_UNION);
+ elem = builtin_type (gdbarch)->builtin_uint8;
+ append_composite_type_field (t, "u8", init_vector_type (elem, 16));
+ elem = builtin_type (gdbarch)->builtin_uint16;
+ append_composite_type_field (t, "u16", init_vector_type (elem, 8));
+ elem = builtin_type (gdbarch)->builtin_uint32;
+ append_composite_type_field (t, "u32", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_uint64;
+ append_composite_type_field (t, "u64", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_float;
+ append_composite_type_field (t, "f32", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_double;
+ append_composite_type_field (t, "f64", init_vector_type (elem, 2));
+
+ TYPE_VECTOR (t) = 1;
+ TYPE_NAME (t) = "neon_q";
+ tdep->neon_quad_type = t;
+ }
+
+ return tdep->neon_quad_type;
+}
+
+/* Return the GDB type object for the "standard" data type of data in
+ register N. */
+
+static struct type *
+arm_register_type (struct gdbarch *gdbarch, int regnum)
+{
+ int num_regs = gdbarch_num_regs (gdbarch);
+
+ if (gdbarch_tdep (gdbarch)->have_vfp_pseudos
+ && regnum >= num_regs && regnum < num_regs + 32)
+ return builtin_type (gdbarch)->builtin_float;
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos
+ && regnum >= num_regs + 32 && regnum < num_regs + 32 + 16)
+ return arm_neon_quad_type (gdbarch);
+
+ /* If the target description has register information, we are only
+ in this function so that we can override the types of
+ double-precision registers for NEON. */
+ if (tdesc_has_registers (gdbarch_target_desc (gdbarch)))
+ {
+ struct type *t = tdesc_register_type (gdbarch, regnum);
+
+ if (regnum >= ARM_D0_REGNUM && regnum < ARM_D0_REGNUM + 32
+ && TYPE_CODE (t) == TYPE_CODE_FLT
+ && gdbarch_tdep (gdbarch)->have_neon)
+ return arm_neon_double_type (gdbarch);
+ else
+ return t;
+ }
+
+ if (regnum >= ARM_F0_REGNUM && regnum < ARM_F0_REGNUM + NUM_FREGS)
+ {
+ if (!gdbarch_tdep (gdbarch)->have_fpa_registers)
+ return builtin_type (gdbarch)->builtin_void;
+
+ return arm_ext_type (gdbarch);
+ }
+ else if (regnum == ARM_SP_REGNUM)
+ return builtin_type (gdbarch)->builtin_data_ptr;
+ else if (regnum == ARM_PC_REGNUM)
+ return builtin_type (gdbarch)->builtin_func_ptr;
+ else if (regnum >= ARRAY_SIZE (arm_register_names))
+ /* These registers are only supported on targets which supply
+ an XML description. */
+ return builtin_type (gdbarch)->builtin_int0;
+ else
+ return builtin_type (gdbarch)->builtin_uint32;
+}
+
+/* Map a DWARF register REGNUM onto the appropriate GDB register
+ number. */
+
+static int
+arm_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg)
+{
+ /* Core integer regs. */
+ if (reg >= 0 && reg <= 15)
+ return reg;
+
+ /* Legacy FPA encoding. These were once used in a way which
+ overlapped with VFP register numbering, so their use is
+ discouraged, but GDB doesn't support the ARM toolchain
+ which used them for VFP. */
+ if (reg >= 16 && reg <= 23)
+ return ARM_F0_REGNUM + reg - 16;
+
+ /* New assignments for the FPA registers. */
+ if (reg >= 96 && reg <= 103)
+ return ARM_F0_REGNUM + reg - 96;
+
+ /* WMMX register assignments. */
+ if (reg >= 104 && reg <= 111)
+ return ARM_WCGR0_REGNUM + reg - 104;
+
+ if (reg >= 112 && reg <= 127)
+ return ARM_WR0_REGNUM + reg - 112;
+
+ if (reg >= 192 && reg <= 199)
+ return ARM_WC0_REGNUM + reg - 192;
+
+ /* VFP v2 registers. A double precision value is actually
+ in d1 rather than s2, but the ABI only defines numbering
+ for the single precision registers. This will "just work"
+ in GDB for little endian targets (we'll read eight bytes,
+ starting in s0 and then progressing to s1), but will be
+ reversed on big endian targets with VFP. This won't
+ be a problem for the new Neon quad registers; you're supposed
+ to use DW_OP_piece for those. */
+ if (reg >= 64 && reg <= 95)
+ {
+ char name_buf[4];
+
+ sprintf (name_buf, "s%d", reg - 64);
+ return user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ }
+
+ /* VFP v3 / Neon registers. This range is also used for VFP v2
+ registers, except that it now describes d0 instead of s0. */
+ if (reg >= 256 && reg <= 287)
+ {
+ char name_buf[4];
+
+ sprintf (name_buf, "d%d", reg - 256);
+ return user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ }
+
+ return -1;
+}
+
+/* Map GDB internal REGNUM onto the Arm simulator register numbers. */
+static int
+arm_register_sim_regno (struct gdbarch *gdbarch, int regnum)
+{
+ int reg = regnum;
+ gdb_assert (reg >= 0 && reg < gdbarch_num_regs (gdbarch));
+
+ if (regnum >= ARM_WR0_REGNUM && regnum <= ARM_WR15_REGNUM)
+ return regnum - ARM_WR0_REGNUM + SIM_ARM_IWMMXT_COP0R0_REGNUM;
+
+ if (regnum >= ARM_WC0_REGNUM && regnum <= ARM_WC7_REGNUM)
+ return regnum - ARM_WC0_REGNUM + SIM_ARM_IWMMXT_COP1R0_REGNUM;
+
+ if (regnum >= ARM_WCGR0_REGNUM && regnum <= ARM_WCGR7_REGNUM)
+ return regnum - ARM_WCGR0_REGNUM + SIM_ARM_IWMMXT_COP1R8_REGNUM;
+
+ if (reg < NUM_GREGS)
+ return SIM_ARM_R0_REGNUM + reg;
+ reg -= NUM_GREGS;
+
+ if (reg < NUM_FREGS)
+ return SIM_ARM_FP0_REGNUM + reg;
+ reg -= NUM_FREGS;
+
+ if (reg < NUM_SREGS)
+ return SIM_ARM_FPS_REGNUM + reg;
+ reg -= NUM_SREGS;
+
+ internal_error (__FILE__, __LINE__, _("Bad REGNUM %d"), regnum);
+}
+
+/* NOTE: cagney/2001-08-20: Both convert_from_extended() and
+ convert_to_extended() use floatformat_arm_ext_littlebyte_bigword.
+ It is thought that this is is the floating-point register format on
+ little-endian systems. */
+
+static void
+convert_from_extended (const struct floatformat *fmt, const void *ptr,
+ void *dbl, int endianess)
+{
+ DOUBLEST d;
+
+ if (endianess == BFD_ENDIAN_BIG)
+ floatformat_to_doublest (&floatformat_arm_ext_big, ptr, &d);
+ else
+ floatformat_to_doublest (&floatformat_arm_ext_littlebyte_bigword,
+ ptr, &d);
+ floatformat_from_doublest (fmt, &d, dbl);
+}
+
+static void
+convert_to_extended (const struct floatformat *fmt, void *dbl, const void *ptr,
+ int endianess)
+{
+ DOUBLEST d;
+
+ floatformat_to_doublest (fmt, ptr, &d);
+ if (endianess == BFD_ENDIAN_BIG)
+ floatformat_from_doublest (&floatformat_arm_ext_big, &d, dbl);
+ else
+ floatformat_from_doublest (&floatformat_arm_ext_littlebyte_bigword,
+ &d, dbl);
+}
+
+static int
+condition_true (unsigned long cond, unsigned long status_reg)
+{
+ if (cond == INST_AL || cond == INST_NV)
+ return 1;
+
+ switch (cond)
+ {
+ case INST_EQ:
+ return ((status_reg & FLAG_Z) != 0);
+ case INST_NE:
+ return ((status_reg & FLAG_Z) == 0);
+ case INST_CS:
return ((status_reg & FLAG_C) != 0);
case INST_CC:
return ((status_reg & FLAG_C) == 0);
|| (((status_reg & FLAG_N) == 0)
!= ((status_reg & FLAG_V) == 0)));
}
- return 1;
+ return 1;
+}
+
+static unsigned long
+shifted_reg_val (struct frame_info *frame, unsigned long inst, int carry,
+ unsigned long pc_val, unsigned long status_reg)
+{
+ unsigned long res, shift;
+ int rm = bits (inst, 0, 3);
+ unsigned long shifttype = bits (inst, 5, 6);
+
+ if (bit (inst, 4))
+ {
+ int rs = bits (inst, 8, 11);
+ shift = (rs == 15 ? pc_val + 8
+ : get_frame_register_unsigned (frame, rs)) & 0xFF;
+ }
+ else
+ shift = bits (inst, 7, 11);
+
+ res = (rm == ARM_PC_REGNUM
+ ? (pc_val + (bit (inst, 4) ? 12 : 8))
+ : get_frame_register_unsigned (frame, rm));
+
+ switch (shifttype)
+ {
+ case 0: /* LSL */
+ res = shift >= 32 ? 0 : res << shift;
+ break;
+
+ case 1: /* LSR */
+ res = shift >= 32 ? 0 : res >> shift;
+ break;
+
+ case 2: /* ASR */
+ if (shift >= 32)
+ shift = 31;
+ res = ((res & 0x80000000L)
+ ? ~((~res) >> shift) : res >> shift);
+ break;
+
+ case 3: /* ROR/RRX */
+ shift &= 31;
+ if (shift == 0)
+ res = (res >> 1) | (carry ? 0x80000000L : 0);
+ else
+ res = (res >> shift) | (res << (32 - shift));
+ break;
+ }
+
+ return res & 0xffffffff;
+}
+
+/* Return number of 1-bits in VAL. */
+
+static int
+bitcount (unsigned long val)
+{
+ int nbits;
+ for (nbits = 0; val != 0; nbits++)
+ val &= val - 1; /* Delete rightmost 1-bit in val. */
+ return nbits;
+}
+
+/* Return the size in bytes of the complete Thumb instruction whose
+ first halfword is INST1. */
+
+static int
+thumb_insn_size (unsigned short inst1)
+{
+ if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0)
+ return 4;
+ else
+ return 2;
+}
+
+static int
+thumb_advance_itstate (unsigned int itstate)
+{
+ /* Preserve IT[7:5], the first three bits of the condition. Shift
+ the upcoming condition flags left by one bit. */
+ itstate = (itstate & 0xe0) | ((itstate << 1) & 0x1f);
+
+ /* If we have finished the IT block, clear the state. */
+ if ((itstate & 0x0f) == 0)
+ itstate = 0;
+
+ return itstate;
+}
+
+/* Find the next PC after the current instruction executes. In some
+ cases we can not statically determine the answer (see the IT state
+ handling in this function); in that case, a breakpoint may be
+ inserted in addition to the returned PC, which will be used to set
+ another breakpoint by our caller. */
+
+static CORE_ADDR
+thumb_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct address_space *aspace = get_frame_address_space (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */
+ unsigned short inst1;
+ CORE_ADDR nextpc = pc + 2; /* Default is next instruction. */
+ unsigned long offset;
+ ULONGEST status, itstate;
+
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+ pc_val = MAKE_THUMB_ADDR (pc_val);
+
+ inst1 = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
+
+ /* Thumb-2 conditional execution support. There are eight bits in
+ the CPSR which describe conditional execution state. Once
+ reconstructed (they're in a funny order), the low five bits
+ describe the low bit of the condition for each instruction and
+ how many instructions remain. The high three bits describe the
+ base condition. One of the low four bits will be set if an IT
+ block is active. These bits read as zero on earlier
+ processors. */
+ status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
+ itstate = ((status >> 8) & 0xfc) | ((status >> 25) & 0x3);
+
+ /* If-Then handling. On GNU/Linux, where this routine is used, we
+ use an undefined instruction as a breakpoint. Unlike BKPT, IT
+ can disable execution of the undefined instruction. So we might
+ miss the breakpoint if we set it on a skipped conditional
+ instruction. Because conditional instructions can change the
+ flags, affecting the execution of further instructions, we may
+ need to set two breakpoints. */
+
+ if (gdbarch_tdep (gdbarch)->thumb2_breakpoint != NULL)
+ {
+ if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
+ {
+ /* An IT instruction. Because this instruction does not
+ modify the flags, we can accurately predict the next
+ executed instruction. */
+ itstate = inst1 & 0x00ff;
+ pc += thumb_insn_size (inst1);
+
+ while (itstate != 0 && ! condition_true (itstate >> 4, status))
+ {
+ inst1 = read_memory_unsigned_integer (pc, 2,
+ byte_order_for_code);
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+ }
+
+ return MAKE_THUMB_ADDR (pc);
+ }
+ else if (itstate != 0)
+ {
+ /* We are in a conditional block. Check the condition. */
+ if (! condition_true (itstate >> 4, status))
+ {
+ /* Advance to the next executed instruction. */
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+
+ while (itstate != 0 && ! condition_true (itstate >> 4, status))
+ {
+ inst1 = read_memory_unsigned_integer (pc, 2,
+ byte_order_for_code);
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+ }
+
+ return MAKE_THUMB_ADDR (pc);
+ }
+ else if ((itstate & 0x0f) == 0x08)
+ {
+ /* This is the last instruction of the conditional
+ block, and it is executed. We can handle it normally
+ because the following instruction is not conditional,
+ and we must handle it normally because it is
+ permitted to branch. Fall through. */
+ }
+ else
+ {
+ int cond_negated;
+
+ /* There are conditional instructions after this one.
+ If this instruction modifies the flags, then we can
+ not predict what the next executed instruction will
+ be. Fortunately, this instruction is architecturally
+ forbidden to branch; we know it will fall through.
+ Start by skipping past it. */
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+
+ /* Set a breakpoint on the following instruction. */
+ gdb_assert ((itstate & 0x0f) != 0);
+ arm_insert_single_step_breakpoint (gdbarch, aspace,
+ MAKE_THUMB_ADDR (pc));
+ cond_negated = (itstate >> 4) & 1;
+
+ /* Skip all following instructions with the same
+ condition. If there is a later instruction in the IT
+ block with the opposite condition, set the other
+ breakpoint there. If not, then set a breakpoint on
+ the instruction after the IT block. */
+ do
+ {
+ inst1 = read_memory_unsigned_integer (pc, 2,
+ byte_order_for_code);
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+ }
+ while (itstate != 0 && ((itstate >> 4) & 1) == cond_negated);
+
+ return MAKE_THUMB_ADDR (pc);
+ }
+ }
+ }
+ else if (itstate & 0x0f)
+ {
+ /* We are in a conditional block. Check the condition. */
+ int cond = itstate >> 4;
+
+ if (! condition_true (cond, status))
+ /* Advance to the next instruction. All the 32-bit
+ instructions share a common prefix. */
+ return MAKE_THUMB_ADDR (pc + thumb_insn_size (inst1));
+
+ /* Otherwise, handle the instruction normally. */
+ }
+
+ if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */
+ {
+ CORE_ADDR sp;
+
+ /* Fetch the saved PC from the stack. It's stored above
+ all of the other registers. */
+ offset = bitcount (bits (inst1, 0, 7)) * INT_REGISTER_SIZE;
+ sp = get_frame_register_unsigned (frame, ARM_SP_REGNUM);
+ nextpc = read_memory_unsigned_integer (sp + offset, 4, byte_order);
+ }
+ else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
+ {
+ unsigned long cond = bits (inst1, 8, 11);
+ if (cond == 0x0f) /* 0x0f = SWI */
+ {
+ struct gdbarch_tdep *tdep;
+ tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->syscall_next_pc != NULL)
+ nextpc = tdep->syscall_next_pc (frame);
+
+ }
+ else if (cond != 0x0f && condition_true (cond, status))
+ nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
+ }
+ else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */
+ {
+ nextpc = pc_val + (sbits (inst1, 0, 10) << 1);
+ }
+ else if (thumb_insn_size (inst1) == 4) /* 32-bit instruction */
+ {
+ unsigned short inst2;
+ inst2 = read_memory_unsigned_integer (pc + 2, 2, byte_order_for_code);
+
+ /* Default to the next instruction. */
+ nextpc = pc + 4;
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+
+ if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000)
+ {
+ /* Branches and miscellaneous control instructions. */
+
+ if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000)
+ {
+ /* B, BL, BLX. */
+ int j1, j2, imm1, imm2;
+
+ imm1 = sbits (inst1, 0, 10);
+ imm2 = bits (inst2, 0, 10);
+ j1 = bit (inst2, 13);
+ j2 = bit (inst2, 11);
+
+ offset = ((imm1 << 12) + (imm2 << 1));
+ offset ^= ((!j2) << 22) | ((!j1) << 23);
+
+ nextpc = pc_val + offset;
+ /* For BLX make sure to clear the low bits. */
+ if (bit (inst2, 12) == 0)
+ nextpc = nextpc & 0xfffffffc;
+ }
+ else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00)
+ {
+ /* SUBS PC, LR, #imm8. */
+ nextpc = get_frame_register_unsigned (frame, ARM_LR_REGNUM);
+ nextpc -= inst2 & 0x00ff;
+ }
+ else if ((inst2 & 0xd000) == 0x8000 && (inst1 & 0x0380) != 0x0380)
+ {
+ /* Conditional branch. */
+ if (condition_true (bits (inst1, 6, 9), status))
+ {
+ int sign, j1, j2, imm1, imm2;
+
+ sign = sbits (inst1, 10, 10);
+ imm1 = bits (inst1, 0, 5);
+ imm2 = bits (inst2, 0, 10);
+ j1 = bit (inst2, 13);
+ j2 = bit (inst2, 11);
+
+ offset = (sign << 20) + (j2 << 19) + (j1 << 18);
+ offset += (imm1 << 12) + (imm2 << 1);
+
+ nextpc = pc_val + offset;
+ }
+ }
+ }
+ else if ((inst1 & 0xfe50) == 0xe810)
+ {
+ /* Load multiple or RFE. */
+ int rn, offset, load_pc = 1;
+
+ rn = bits (inst1, 0, 3);
+ if (bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* LDMIA or POP */
+ if (!bit (inst2, 15))
+ load_pc = 0;
+ offset = bitcount (inst2) * 4 - 4;
+ }
+ else if (!bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* LDMDB */
+ if (!bit (inst2, 15))
+ load_pc = 0;
+ offset = -4;
+ }
+ else if (bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* RFEIA */
+ offset = 0;
+ }
+ else if (!bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* RFEDB */
+ offset = -8;
+ }
+ else
+ load_pc = 0;
+
+ if (load_pc)
+ {
+ CORE_ADDR addr = get_frame_register_unsigned (frame, rn);
+ nextpc = get_frame_memory_unsigned (frame, addr + offset, 4);
+ }
+ }
+ else if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00)
+ {
+ /* MOV PC or MOVS PC. */
+ nextpc = get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+ }
+ else if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000)
+ {
+ /* LDR PC. */
+ CORE_ADDR base;
+ int rn, load_pc = 1;
+
+ rn = bits (inst1, 0, 3);
+ base = get_frame_register_unsigned (frame, rn);
+ if (rn == ARM_PC_REGNUM)
+ {
+ base = (base + 4) & ~(CORE_ADDR) 0x3;
+ if (bit (inst1, 7))
+ base += bits (inst2, 0, 11);
+ else
+ base -= bits (inst2, 0, 11);
+ }
+ else if (bit (inst1, 7))
+ base += bits (inst2, 0, 11);
+ else if (bit (inst2, 11))
+ {
+ if (bit (inst2, 10))
+ {
+ if (bit (inst2, 9))
+ base += bits (inst2, 0, 7);
+ else
+ base -= bits (inst2, 0, 7);
+ }
+ }
+ else if ((inst2 & 0x0fc0) == 0x0000)
+ {
+ int shift = bits (inst2, 4, 5), rm = bits (inst2, 0, 3);
+ base += get_frame_register_unsigned (frame, rm) << shift;
+ }
+ else
+ /* Reserved. */
+ load_pc = 0;
+
+ if (load_pc)
+ nextpc = get_frame_memory_unsigned (frame, base, 4);
+ }
+ else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000)
+ {
+ /* TBB. */
+ CORE_ADDR tbl_reg, table, offset, length;
+
+ tbl_reg = bits (inst1, 0, 3);
+ if (tbl_reg == 0x0f)
+ table = pc + 4; /* Regcache copy of PC isn't right yet. */
+ else
+ table = get_frame_register_unsigned (frame, tbl_reg);
+
+ offset = get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ length = 2 * get_frame_memory_unsigned (frame, table + offset, 1);
+ nextpc = pc_val + length;
+ }
+ else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf010)
+ {
+ /* TBH. */
+ CORE_ADDR tbl_reg, table, offset, length;
+
+ tbl_reg = bits (inst1, 0, 3);
+ if (tbl_reg == 0x0f)
+ table = pc + 4; /* Regcache copy of PC isn't right yet. */
+ else
+ table = get_frame_register_unsigned (frame, tbl_reg);
+
+ offset = 2 * get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ length = 2 * get_frame_memory_unsigned (frame, table + offset, 2);
+ nextpc = pc_val + length;
+ }
+ }
+ else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
+ {
+ if (bits (inst1, 3, 6) == 0x0f)
+ nextpc = pc_val;
+ else
+ nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6));
+ }
+ else if ((inst1 & 0xff87) == 0x4687) /* mov pc, REG */
+ {
+ if (bits (inst1, 3, 6) == 0x0f)
+ nextpc = pc_val;
+ else
+ nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6));
+
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+ }
+ else if ((inst1 & 0xf500) == 0xb100)
+ {
+ /* CBNZ or CBZ. */
+ int imm = (bit (inst1, 9) << 6) + (bits (inst1, 3, 7) << 1);
+ ULONGEST reg = get_frame_register_unsigned (frame, bits (inst1, 0, 2));
+
+ if (bit (inst1, 11) && reg != 0)
+ nextpc = pc_val + imm;
+ else if (!bit (inst1, 11) && reg == 0)
+ nextpc = pc_val + imm;
+ }
+ return nextpc;
+}
+
+/* Get the raw next address. PC is the current program counter, in
+ FRAME, which is assumed to be executing in ARM mode.
+
+ The value returned has the execution state of the next instruction
+ encoded in it. Use IS_THUMB_ADDR () to see whether the instruction is
+ in Thumb-State, and gdbarch_addr_bits_remove () to get the plain memory
+ address. */
+
+static CORE_ADDR
+arm_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned long pc_val;
+ unsigned long this_instr;
+ unsigned long status;
+ CORE_ADDR nextpc;
+
+ pc_val = (unsigned long) pc;
+ this_instr = read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+
+ status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
+ nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
+
+ if (bits (this_instr, 28, 31) == INST_NV)
+ switch (bits (this_instr, 24, 27))
+ {
+ case 0xa:
+ case 0xb:
+ {
+ /* Branch with Link and change to Thumb. */
+ nextpc = BranchDest (pc, this_instr);
+ nextpc |= bit (this_instr, 24) << 1;
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+ break;
+ }
+ case 0xc:
+ case 0xd:
+ case 0xe:
+ /* Coprocessor register transfer. */
+ if (bits (this_instr, 12, 15) == 15)
+ error (_("Invalid update to pc in instruction"));
+ break;
+ }
+ else if (condition_true (bits (this_instr, 28, 31), status))
+ {
+ switch (bits (this_instr, 24, 27))
+ {
+ case 0x0:
+ case 0x1: /* data processing */
+ case 0x2:
+ case 0x3:
+ {
+ unsigned long operand1, operand2, result = 0;
+ unsigned long rn;
+ int c;
+
+ if (bits (this_instr, 12, 15) != 15)
+ break;
+
+ if (bits (this_instr, 22, 25) == 0
+ && bits (this_instr, 4, 7) == 9) /* multiply */
+ error (_("Invalid update to pc in instruction"));
+
+ /* BX <reg>, BLX <reg> */
+ if (bits (this_instr, 4, 27) == 0x12fff1
+ || bits (this_instr, 4, 27) == 0x12fff3)
+ {
+ rn = bits (this_instr, 0, 3);
+ nextpc = ((rn == ARM_PC_REGNUM)
+ ? (pc_val + 8)
+ : get_frame_register_unsigned (frame, rn));
+
+ return nextpc;
+ }
+
+ /* Multiply into PC. */
+ c = (status & FLAG_C) ? 1 : 0;
+ rn = bits (this_instr, 16, 19);
+ operand1 = ((rn == ARM_PC_REGNUM)
+ ? (pc_val + 8)
+ : get_frame_register_unsigned (frame, rn));
+
+ if (bit (this_instr, 25))
+ {
+ unsigned long immval = bits (this_instr, 0, 7);
+ unsigned long rotate = 2 * bits (this_instr, 8, 11);
+ operand2 = ((immval >> rotate) | (immval << (32 - rotate)))
+ & 0xffffffff;
+ }
+ else /* operand 2 is a shifted register. */
+ operand2 = shifted_reg_val (frame, this_instr, c,
+ pc_val, status);
+
+ switch (bits (this_instr, 21, 24))
+ {
+ case 0x0: /*and */
+ result = operand1 & operand2;
+ break;
+
+ case 0x1: /*eor */
+ result = operand1 ^ operand2;
+ break;
+
+ case 0x2: /*sub */
+ result = operand1 - operand2;
+ break;
+
+ case 0x3: /*rsb */
+ result = operand2 - operand1;
+ break;
+
+ case 0x4: /*add */
+ result = operand1 + operand2;
+ break;
+
+ case 0x5: /*adc */
+ result = operand1 + operand2 + c;
+ break;
+
+ case 0x6: /*sbc */
+ result = operand1 - operand2 + c;
+ break;
+
+ case 0x7: /*rsc */
+ result = operand2 - operand1 + c;
+ break;
+
+ case 0x8:
+ case 0x9:
+ case 0xa:
+ case 0xb: /* tst, teq, cmp, cmn */
+ result = (unsigned long) nextpc;
+ break;
+
+ case 0xc: /*orr */
+ result = operand1 | operand2;
+ break;
+
+ case 0xd: /*mov */
+ /* Always step into a function. */
+ result = operand2;
+ break;
+
+ case 0xe: /*bic */
+ result = operand1 & ~operand2;
+ break;
+
+ case 0xf: /*mvn */
+ result = ~operand2;
+ break;
+ }
+
+ /* In 26-bit APCS the bottom two bits of the result are
+ ignored, and we always end up in ARM state. */
+ if (!arm_apcs_32)
+ nextpc = arm_addr_bits_remove (gdbarch, result);
+ else
+ nextpc = result;
+
+ break;
+ }
+
+ case 0x4:
+ case 0x5: /* data transfer */
+ case 0x6:
+ case 0x7:
+ if (bit (this_instr, 20))
+ {
+ /* load */
+ if (bits (this_instr, 12, 15) == 15)
+ {
+ /* rd == pc */
+ unsigned long rn;
+ unsigned long base;
+
+ if (bit (this_instr, 22))
+ error (_("Invalid update to pc in instruction"));
+
+ /* byte write to PC */
+ rn = bits (this_instr, 16, 19);
+ base = ((rn == ARM_PC_REGNUM)
+ ? (pc_val + 8)
+ : get_frame_register_unsigned (frame, rn));
+
+ if (bit (this_instr, 24))
+ {
+ /* pre-indexed */
+ int c = (status & FLAG_C) ? 1 : 0;
+ unsigned long offset =
+ (bit (this_instr, 25)
+ ? shifted_reg_val (frame, this_instr, c, pc_val, status)
+ : bits (this_instr, 0, 11));
+
+ if (bit (this_instr, 23))
+ base += offset;
+ else
+ base -= offset;
+ }
+ nextpc =
+ (CORE_ADDR) read_memory_unsigned_integer ((CORE_ADDR) base,
+ 4, byte_order);
+ }
+ }
+ break;
+
+ case 0x8:
+ case 0x9: /* block transfer */
+ if (bit (this_instr, 20))
+ {
+ /* LDM */
+ if (bit (this_instr, 15))
+ {
+ /* loading pc */
+ int offset = 0;
+ unsigned long rn_val
+ = get_frame_register_unsigned (frame,
+ bits (this_instr, 16, 19));
+
+ if (bit (this_instr, 23))
+ {
+ /* up */
+ unsigned long reglist = bits (this_instr, 0, 14);
+ offset = bitcount (reglist) * 4;
+ if (bit (this_instr, 24)) /* pre */
+ offset += 4;
+ }
+ else if (bit (this_instr, 24))
+ offset = -4;
+
+ nextpc =
+ (CORE_ADDR) read_memory_unsigned_integer ((CORE_ADDR)
+ (rn_val + offset),
+ 4, byte_order);
+ }
+ }
+ break;
+
+ case 0xb: /* branch & link */
+ case 0xa: /* branch */
+ {
+ nextpc = BranchDest (pc, this_instr);
+ break;
+ }
+
+ case 0xc:
+ case 0xd:
+ case 0xe: /* coproc ops */
+ break;
+ case 0xf: /* SWI */
+ {
+ struct gdbarch_tdep *tdep;
+ tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->syscall_next_pc != NULL)
+ nextpc = tdep->syscall_next_pc (frame);
+
+ }
+ break;
+
+ default:
+ fprintf_filtered (gdb_stderr, _("Bad bit-field extraction\n"));
+ return (pc);
+ }
+ }
+
+ return nextpc;
+}
+
+/* Determine next PC after current instruction executes. Will call either
+ arm_get_next_pc_raw or thumb_get_next_pc_raw. Error out if infinite
+ loop is detected. */
+
+CORE_ADDR
+arm_get_next_pc (struct frame_info *frame, CORE_ADDR pc)
+{
+ CORE_ADDR nextpc;
+
+ if (arm_frame_is_thumb (frame))
+ {
+ nextpc = thumb_get_next_pc_raw (frame, pc);
+ if (nextpc == MAKE_THUMB_ADDR (pc))
+ error (_("Infinite loop detected"));
+ }
+ else
+ {
+ nextpc = arm_get_next_pc_raw (frame, pc);
+ if (nextpc == pc)
+ error (_("Infinite loop detected"));
+ }
+
+ return nextpc;
+}
+
+/* Like insert_single_step_breakpoint, but make sure we use a breakpoint
+ of the appropriate mode (as encoded in the PC value), even if this
+ differs from what would be expected according to the symbol tables. */
+
+void
+arm_insert_single_step_breakpoint (struct gdbarch *gdbarch,
+ struct address_space *aspace,
+ CORE_ADDR pc)
+{
+ struct cleanup *old_chain
+ = make_cleanup_restore_integer (&arm_override_mode);
+
+ arm_override_mode = IS_THUMB_ADDR (pc);
+ pc = gdbarch_addr_bits_remove (gdbarch, pc);
+
+ insert_single_step_breakpoint (gdbarch, aspace, pc);
+
+ do_cleanups (old_chain);
+}
+
+/* single_step() is called just before we want to resume the inferior,
+ if we want to single-step it but there is no hardware or kernel
+ single-step support. We find the target of the coming instruction
+ and breakpoint it. */
+
+int
+arm_software_single_step (struct frame_info *frame)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct address_space *aspace = get_frame_address_space (frame);
+ CORE_ADDR next_pc = arm_get_next_pc (frame, get_frame_pc (frame));
+
+ arm_insert_single_step_breakpoint (gdbarch, aspace, next_pc);
+
+ return 1;
+}
+
+/* Given BUF, which is OLD_LEN bytes ending at ENDADDR, expand
+ the buffer to be NEW_LEN bytes ending at ENDADDR. Return
+ NULL if an error occurs. BUF is freed. */
+
+static gdb_byte *
+extend_buffer_earlier (gdb_byte *buf, CORE_ADDR endaddr,
+ int old_len, int new_len)
+{
+ gdb_byte *new_buf, *middle;
+ int bytes_to_read = new_len - old_len;
+
+ new_buf = xmalloc (new_len);
+ memcpy (new_buf + bytes_to_read, buf, old_len);
+ xfree (buf);
+ if (target_read_memory (endaddr - new_len, new_buf, bytes_to_read) != 0)
+ {
+ xfree (new_buf);
+ return NULL;
+ }
+ return new_buf;
+}
+
+/* An IT block is at most the 2-byte IT instruction followed by
+ four 4-byte instructions. The furthest back we must search to
+ find an IT block that affects the current instruction is thus
+ 2 + 3 * 4 == 14 bytes. */
+#define MAX_IT_BLOCK_PREFIX 14
+
+/* Use a quick scan if there are more than this many bytes of
+ code. */
+#define IT_SCAN_THRESHOLD 32
+
+/* Adjust a breakpoint's address to move breakpoints out of IT blocks.
+ A breakpoint in an IT block may not be hit, depending on the
+ condition flags. */
+static CORE_ADDR
+arm_adjust_breakpoint_address (struct gdbarch *gdbarch, CORE_ADDR bpaddr)
+{
+ gdb_byte *buf;
+ char map_type;
+ CORE_ADDR boundary, func_start;
+ int buf_len, buf2_len;
+ enum bfd_endian order = gdbarch_byte_order_for_code (gdbarch);
+ int i, any, last_it, last_it_count;
+
+ /* If we are using BKPT breakpoints, none of this is necessary. */
+ if (gdbarch_tdep (gdbarch)->thumb2_breakpoint == NULL)
+ return bpaddr;
+
+ /* ARM mode does not have this problem. */
+ if (!arm_pc_is_thumb (gdbarch, bpaddr))
+ return bpaddr;
+
+ /* We are setting a breakpoint in Thumb code that could potentially
+ contain an IT block. The first step is to find how much Thumb
+ code there is; we do not need to read outside of known Thumb
+ sequences. */
+ map_type = arm_find_mapping_symbol (bpaddr, &boundary);
+ if (map_type == 0)
+ /* Thumb-2 code must have mapping symbols to have a chance. */
+ return bpaddr;
+
+ bpaddr = gdbarch_addr_bits_remove (gdbarch, bpaddr);
+
+ if (find_pc_partial_function (bpaddr, NULL, &func_start, NULL)
+ && func_start > boundary)
+ boundary = func_start;
+
+ /* Search for a candidate IT instruction. We have to do some fancy
+ footwork to distinguish a real IT instruction from the second
+ half of a 32-bit instruction, but there is no need for that if
+ there's no candidate. */
+ buf_len = min (bpaddr - boundary, MAX_IT_BLOCK_PREFIX);
+ if (buf_len == 0)
+ /* No room for an IT instruction. */
+ return bpaddr;
+
+ buf = xmalloc (buf_len);
+ if (target_read_memory (bpaddr - buf_len, buf, buf_len) != 0)
+ return bpaddr;
+ any = 0;
+ for (i = 0; i < buf_len; i += 2)
+ {
+ unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
+ if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
+ {
+ any = 1;
+ break;
+ }
+ }
+ if (any == 0)
+ {
+ xfree (buf);
+ return bpaddr;
+ }
+
+ /* OK, the code bytes before this instruction contain at least one
+ halfword which resembles an IT instruction. We know that it's
+ Thumb code, but there are still two possibilities. Either the
+ halfword really is an IT instruction, or it is the second half of
+ a 32-bit Thumb instruction. The only way we can tell is to
+ scan forwards from a known instruction boundary. */
+ if (bpaddr - boundary > IT_SCAN_THRESHOLD)
+ {
+ int definite;
+
+ /* There's a lot of code before this instruction. Start with an
+ optimistic search; it's easy to recognize halfwords that can
+ not be the start of a 32-bit instruction, and use that to
+ lock on to the instruction boundaries. */
+ buf = extend_buffer_earlier (buf, bpaddr, buf_len, IT_SCAN_THRESHOLD);
+ if (buf == NULL)
+ return bpaddr;
+ buf_len = IT_SCAN_THRESHOLD;
+
+ definite = 0;
+ for (i = 0; i < buf_len - sizeof (buf) && ! definite; i += 2)
+ {
+ unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
+ if (thumb_insn_size (inst1) == 2)
+ {
+ definite = 1;
+ break;
+ }
+ }
+
+ /* At this point, if DEFINITE, BUF[I] is the first place we
+ are sure that we know the instruction boundaries, and it is far
+ enough from BPADDR that we could not miss an IT instruction
+ affecting BPADDR. If ! DEFINITE, give up - start from a
+ known boundary. */
+ if (! definite)
+ {
+ buf = extend_buffer_earlier (buf, bpaddr, buf_len,
+ bpaddr - boundary);
+ if (buf == NULL)
+ return bpaddr;
+ buf_len = bpaddr - boundary;
+ i = 0;
+ }
+ }
+ else
+ {
+ buf = extend_buffer_earlier (buf, bpaddr, buf_len, bpaddr - boundary);
+ if (buf == NULL)
+ return bpaddr;
+ buf_len = bpaddr - boundary;
+ i = 0;
+ }
+
+ /* Scan forwards. Find the last IT instruction before BPADDR. */
+ last_it = -1;
+ last_it_count = 0;
+ while (i < buf_len)
+ {
+ unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
+ last_it_count--;
+ if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
+ {
+ last_it = i;
+ if (inst1 & 0x0001)
+ last_it_count = 4;
+ else if (inst1 & 0x0002)
+ last_it_count = 3;
+ else if (inst1 & 0x0004)
+ last_it_count = 2;
+ else
+ last_it_count = 1;
+ }
+ i += thumb_insn_size (inst1);
+ }
+
+ xfree (buf);
+
+ if (last_it == -1)
+ /* There wasn't really an IT instruction after all. */
+ return bpaddr;
+
+ if (last_it_count < 1)
+ /* It was too far away. */
+ return bpaddr;
+
+ /* This really is a trouble spot. Move the breakpoint to the IT
+ instruction. */
+ return bpaddr - buf_len + last_it;
+}
+
+/* ARM displaced stepping support.
+
+ Generally ARM displaced stepping works as follows:
+
+ 1. When an instruction is to be single-stepped, it is first decoded by
+ arm_process_displaced_insn (called from arm_displaced_step_copy_insn).
+ Depending on the type of instruction, it is then copied to a scratch
+ location, possibly in a modified form. The copy_* set of functions
+ performs such modification, as necessary. A breakpoint is placed after
+ the modified instruction in the scratch space to return control to GDB.
+ Note in particular that instructions which modify the PC will no longer
+ do so after modification.
+
+ 2. The instruction is single-stepped, by setting the PC to the scratch
+ location address, and resuming. Control returns to GDB when the
+ breakpoint is hit.
+
+ 3. A cleanup function (cleanup_*) is called corresponding to the copy_*
+ function used for the current instruction. This function's job is to
+ put the CPU/memory state back to what it would have been if the
+ instruction had been executed unmodified in its original location. */
+
+/* NOP instruction (mov r0, r0). */
+#define ARM_NOP 0xe1a00000
+#define THUMB_NOP 0x4600
+
+/* Helper for register reads for displaced stepping. In particular, this
+ returns the PC as it would be seen by the instruction at its original
+ location. */
+
+ULONGEST
+displaced_read_reg (struct regcache *regs, struct displaced_step_closure *dsc,
+ int regno)
+{
+ ULONGEST ret;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (regno == ARM_PC_REGNUM)
+ {
+ /* Compute pipeline offset:
+ - When executing an ARM instruction, PC reads as the address of the
+ current instruction plus 8.
+ - When executing a Thumb instruction, PC reads as the address of the
+ current instruction plus 4. */
+
+ if (!dsc->is_thumb)
+ from += 8;
+ else
+ from += 4;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: read pc value %.8lx\n",
+ (unsigned long) from);
+ return (ULONGEST) from;
+ }
+ else
+ {
+ regcache_cooked_read_unsigned (regs, regno, &ret);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: read r%d value %.8lx\n",
+ regno, (unsigned long) ret);
+ return ret;
+ }
+}
+
+static int
+displaced_in_arm_mode (struct regcache *regs)
+{
+ ULONGEST ps;
+ ULONGEST t_bit = arm_psr_thumb_bit (get_regcache_arch (regs));
+
+ regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps);
+
+ return (ps & t_bit) == 0;
+}
+
+/* Write to the PC as from a branch instruction. */
+
+static void
+branch_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+ ULONGEST val)
+{
+ if (!dsc->is_thumb)
+ /* Note: If bits 0/1 are set, this branch would be unpredictable for
+ architecture versions < 6. */
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM,
+ val & ~(ULONGEST) 0x3);
+ else
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM,
+ val & ~(ULONGEST) 0x1);
+}
+
+/* Write to the PC as from a branch-exchange instruction. */
+
+static void
+bx_write_pc (struct regcache *regs, ULONGEST val)
+{
+ ULONGEST ps;
+ ULONGEST t_bit = arm_psr_thumb_bit (get_regcache_arch (regs));
+
+ regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps);
+
+ if ((val & 1) == 1)
+ {
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps | t_bit);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffe);
+ }
+ else if ((val & 2) == 0)
+ {
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps & ~t_bit);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val);
+ }
+ else
+ {
+ /* Unpredictable behaviour. Try to do something sensible (switch to ARM
+ mode, align dest to 4 bytes). */
+ warning (_("Single-stepping BX to non-word-aligned ARM instruction."));
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps & ~t_bit);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffc);
+ }
}
-static unsigned long
-shifted_reg_val (struct frame_info *frame, unsigned long inst, int carry,
- unsigned long pc_val, unsigned long status_reg)
+/* Write to the PC as if from a load instruction. */
+
+static void
+load_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+ ULONGEST val)
{
- unsigned long res, shift;
- int rm = bits (inst, 0, 3);
- unsigned long shifttype = bits (inst, 5, 6);
+ if (DISPLACED_STEPPING_ARCH_VERSION >= 5)
+ bx_write_pc (regs, val);
+ else
+ branch_write_pc (regs, dsc, val);
+}
- if (bit (inst, 4))
+/* Write to the PC as if from an ALU instruction. */
+
+static void
+alu_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+ ULONGEST val)
+{
+ if (DISPLACED_STEPPING_ARCH_VERSION >= 7 && !dsc->is_thumb)
+ bx_write_pc (regs, val);
+ else
+ branch_write_pc (regs, dsc, val);
+}
+
+/* Helper for writing to registers for displaced stepping. Writing to the PC
+ has a varying effects depending on the instruction which does the write:
+ this is controlled by the WRITE_PC argument. */
+
+void
+displaced_write_reg (struct regcache *regs, struct displaced_step_closure *dsc,
+ int regno, ULONGEST val, enum pc_write_style write_pc)
+{
+ if (regno == ARM_PC_REGNUM)
{
- int rs = bits (inst, 8, 11);
- shift = (rs == 15 ? pc_val + 8
- : get_frame_register_unsigned (frame, rs)) & 0xFF;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing pc %.8lx\n",
+ (unsigned long) val);
+ switch (write_pc)
+ {
+ case BRANCH_WRITE_PC:
+ branch_write_pc (regs, dsc, val);
+ break;
+
+ case BX_WRITE_PC:
+ bx_write_pc (regs, val);
+ break;
+
+ case LOAD_WRITE_PC:
+ load_write_pc (regs, dsc, val);
+ break;
+
+ case ALU_WRITE_PC:
+ alu_write_pc (regs, dsc, val);
+ break;
+
+ case CANNOT_WRITE_PC:
+ warning (_("Instruction wrote to PC in an unexpected way when "
+ "single-stepping"));
+ break;
+
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("Invalid argument to displaced_write_reg"));
+ }
+
+ dsc->wrote_to_pc = 1;
}
else
- shift = bits (inst, 7, 11);
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing r%d value %.8lx\n",
+ regno, (unsigned long) val);
+ regcache_cooked_write_unsigned (regs, regno, val);
+ }
+}
- res = (rm == 15
- ? (pc_val + (bit (inst, 4) ? 12 : 8))
- : get_frame_register_unsigned (frame, rm));
+/* This function is used to concisely determine if an instruction INSN
+ references PC. Register fields of interest in INSN should have the
+ corresponding fields of BITMASK set to 0b1111. The function
+ returns return 1 if any of these fields in INSN reference the PC
+ (also 0b1111, r15), else it returns 0. */
- switch (shifttype)
+static int
+insn_references_pc (uint32_t insn, uint32_t bitmask)
+{
+ uint32_t lowbit = 1;
+
+ while (bitmask != 0)
{
- case 0: /* LSL */
- res = shift >= 32 ? 0 : res << shift;
- break;
+ uint32_t mask;
+
+ for (; lowbit && (bitmask & lowbit) == 0; lowbit <<= 1)
+ ;
+
+ if (!lowbit)
+ break;
+
+ mask = lowbit * 0xf;
+
+ if ((insn & mask) == mask)
+ return 1;
+
+ bitmask &= ~mask;
+ }
+
+ return 0;
+}
+
+/* The simplest copy function. Many instructions have the same effect no
+ matter what address they are executed at: in those cases, use this. */
+
+static int
+arm_copy_unmodified (struct gdbarch *gdbarch, uint32_t insn,
+ const char *iname, struct displaced_step_closure *dsc)
+{
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.8lx, "
+ "opcode/class '%s' unmodified\n", (unsigned long) insn,
+ iname);
+
+ dsc->modinsn[0] = insn;
+
+ return 0;
+}
+
+static int
+thumb_copy_unmodified_32bit (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, const char *iname,
+ struct displaced_step_closure *dsc)
+{
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.4x %.4x, "
+ "opcode/class '%s' unmodified\n", insn1, insn2,
+ iname);
+
+ dsc->modinsn[0] = insn1;
+ dsc->modinsn[1] = insn2;
+ dsc->numinsns = 2;
+
+ return 0;
+}
+
+/* Copy 16-bit Thumb(Thumb and 16-bit Thumb-2) instruction without any
+ modification. */
+static int
+thumb_copy_unmodified_16bit (struct gdbarch *gdbarch, unsigned int insn,
+ const char *iname,
+ struct displaced_step_closure *dsc)
+{
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.4x, "
+ "opcode/class '%s' unmodified\n", insn,
+ iname);
+
+ dsc->modinsn[0] = insn;
+
+ return 0;
+}
+
+/* Preload instructions with immediate offset. */
+
+static void
+cleanup_preload (struct gdbarch *gdbarch,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (!dsc->u.preload.immed)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+}
+
+static void
+install_preload (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc, unsigned int rn)
+{
+ ULONGEST rn_val;
+ /* Preload instructions:
+
+ {pli/pld} [rn, #+/-imm]
+ ->
+ {pli/pld} [r0, #+/-imm]. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+ dsc->u.preload.immed = 1;
+
+ dsc->cleanup = &cleanup_preload;
+}
+
+static int
+arm_copy_preload (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+
+ if (!insn_references_pc (insn, 0x000f0000ul))
+ return arm_copy_unmodified (gdbarch, insn, "preload", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n",
+ (unsigned long) insn);
+
+ dsc->modinsn[0] = insn & 0xfff0ffff;
+
+ install_preload (gdbarch, regs, dsc, rn);
+
+ return 0;
+}
+
+static int
+thumb2_copy_preload (struct gdbarch *gdbarch, uint16_t insn1, uint16_t insn2,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn1, 0, 3);
+ unsigned int u_bit = bit (insn1, 7);
+ int imm12 = bits (insn2, 0, 11);
+ ULONGEST pc_val;
+
+ if (rn != ARM_PC_REGNUM)
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2, "preload", dsc);
+
+ /* PC is only allowed to use in PLI (immediate,literal) Encoding T3, and
+ PLD (literal) Encoding T1. */
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying pld/pli pc (0x%x) %c imm12 %.4x\n",
+ (unsigned int) dsc->insn_addr, u_bit ? '+' : '-',
+ imm12);
+
+ if (!u_bit)
+ imm12 = -1 * imm12;
+
+ /* Rewrite instruction {pli/pld} PC imm12 into:
+ Prepare: tmp[0] <- r0, tmp[1] <- r1, r0 <- pc, r1 <- imm12
+
+ {pli/pld} [r0, r1]
+
+ Cleanup: r0 <- tmp[0], r1 <- tmp[1]. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+
+ pc_val = displaced_read_reg (regs, dsc, ARM_PC_REGNUM);
+
+ displaced_write_reg (regs, dsc, 0, pc_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, imm12, CANNOT_WRITE_PC);
+ dsc->u.preload.immed = 0;
+
+ /* {pli/pld} [r0, r1] */
+ dsc->modinsn[0] = insn1 & 0xfff0;
+ dsc->modinsn[1] = 0xf001;
+ dsc->numinsns = 2;
+
+ dsc->cleanup = &cleanup_preload;
+ return 0;
+}
+
+/* Preload instructions with register offset. */
+
+static void
+install_preload_reg(struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc, unsigned int rn,
+ unsigned int rm)
+{
+ ULONGEST rn_val, rm_val;
+
+ /* Preload register-offset instructions:
+
+ {pli/pld} [rn, rm {, shift}]
+ ->
+ {pli/pld} [r0, r1 {, shift}]. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rm_val = displaced_read_reg (regs, dsc, rm);
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rm_val, CANNOT_WRITE_PC);
+ dsc->u.preload.immed = 0;
+
+ dsc->cleanup = &cleanup_preload;
+}
+
+static int
+arm_copy_preload_reg (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+
- case 1: /* LSR */
- res = shift >= 32 ? 0 : res >> shift;
- break;
+ if (!insn_references_pc (insn, 0x000f000ful))
+ return arm_copy_unmodified (gdbarch, insn, "preload reg", dsc);
- case 2: /* ASR */
- if (shift >= 32)
- shift = 31;
- res = ((res & 0x80000000L)
- ? ~((~res) >> shift) : res >> shift);
- break;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n",
+ (unsigned long) insn);
- case 3: /* ROR/RRX */
- shift &= 31;
- if (shift == 0)
- res = (res >> 1) | (carry ? 0x80000000L : 0);
- else
- res = (res >> shift) | (res << (32 - shift));
- break;
- }
+ dsc->modinsn[0] = (insn & 0xfff0fff0) | 0x1;
- return res & 0xffffffff;
+ install_preload_reg (gdbarch, regs, dsc, rn, rm);
+ return 0;
}
-/* Return number of 1-bits in VAL. */
+/* Copy/cleanup coprocessor load and store instructions. */
-static int
-bitcount (unsigned long val)
+static void
+cleanup_copro_load_store (struct gdbarch *gdbarch,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- int nbits;
- for (nbits = 0; val != 0; nbits++)
- val &= val - 1; /* delete rightmost 1-bit in val */
- return nbits;
-}
+ ULONGEST rn_val = displaced_read_reg (regs, dsc, 0);
-/* Return the size in bytes of the complete Thumb instruction whose
- first halfword is INST1. */
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
-static int
-thumb_insn_size (unsigned short inst1)
-{
- if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0)
- return 4;
- else
- return 2;
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, LOAD_WRITE_PC);
}
-static int
-thumb_advance_itstate (unsigned int itstate)
+static void
+install_copro_load_store (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc,
+ int writeback, unsigned int rn)
{
- /* Preserve IT[7:5], the first three bits of the condition. Shift
- the upcoming condition flags left by one bit. */
- itstate = (itstate & 0xe0) | ((itstate << 1) & 0x1f);
+ ULONGEST rn_val;
- /* If we have finished the IT block, clear the state. */
- if ((itstate & 0x0f) == 0)
- itstate = 0;
+ /* Coprocessor load/store instructions:
- return itstate;
-}
+ {stc/stc2} [<Rn>, #+/-imm] (and other immediate addressing modes)
+ ->
+ {stc/stc2} [r0, #+/-imm].
-/* Find the next PC after the current instruction executes. In some
- cases we can not statically determine the answer (see the IT state
- handling in this function); in that case, a breakpoint may be
- inserted in addition to the returned PC, which will be used to set
- another breakpoint by our caller. */
+ ldc/ldc2 are handled identically. */
-static CORE_ADDR
-thumb_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt)
-{
- struct gdbarch *gdbarch = get_frame_arch (frame);
- struct address_space *aspace = get_frame_address_space (frame);
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
- unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */
- unsigned short inst1;
- CORE_ADDR nextpc = pc + 2; /* default is next instruction */
- unsigned long offset;
- ULONGEST status, itstate;
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ /* PC should be 4-byte aligned. */
+ rn_val = rn_val & 0xfffffffc;
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
- nextpc = MAKE_THUMB_ADDR (nextpc);
- pc_val = MAKE_THUMB_ADDR (pc_val);
+ dsc->u.ldst.writeback = writeback;
+ dsc->u.ldst.rn = rn;
- inst1 = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
+ dsc->cleanup = &cleanup_copro_load_store;
+}
- /* Thumb-2 conditional execution support. There are eight bits in
- the CPSR which describe conditional execution state. Once
- reconstructed (they're in a funny order), the low five bits
- describe the low bit of the condition for each instruction and
- how many instructions remain. The high three bits describe the
- base condition. One of the low four bits will be set if an IT
- block is active. These bits read as zero on earlier
- processors. */
- status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
- itstate = ((status >> 8) & 0xfc) | ((status >> 25) & 0x3);
+static int
+arm_copy_copro_load_store (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
- /* If-Then handling. On GNU/Linux, where this routine is used, we
- use an undefined instruction as a breakpoint. Unlike BKPT, IT
- can disable execution of the undefined instruction. So we might
- miss the breakpoint if we set it on a skipped conditional
- instruction. Because conditional instructions can change the
- flags, affecting the execution of further instructions, we may
- need to set two breakpoints. */
+ if (!insn_references_pc (insn, 0x000f0000ul))
+ return arm_copy_unmodified (gdbarch, insn, "copro load/store", dsc);
- if (gdbarch_tdep (gdbarch)->thumb2_breakpoint != NULL)
- {
- if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
- {
- /* An IT instruction. Because this instruction does not
- modify the flags, we can accurately predict the next
- executed instruction. */
- itstate = inst1 & 0x00ff;
- pc += thumb_insn_size (inst1);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying coprocessor "
+ "load/store insn %.8lx\n", (unsigned long) insn);
- while (itstate != 0 && ! condition_true (itstate >> 4, status))
- {
- inst1 = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
- pc += thumb_insn_size (inst1);
- itstate = thumb_advance_itstate (itstate);
- }
+ dsc->modinsn[0] = insn & 0xfff0ffff;
- return MAKE_THUMB_ADDR (pc);
- }
- else if (itstate != 0)
- {
- /* We are in a conditional block. Check the condition. */
- if (! condition_true (itstate >> 4, status))
- {
- /* Advance to the next executed instruction. */
- pc += thumb_insn_size (inst1);
- itstate = thumb_advance_itstate (itstate);
+ install_copro_load_store (gdbarch, regs, dsc, bit (insn, 25), rn);
- while (itstate != 0 && ! condition_true (itstate >> 4, status))
- {
- inst1 = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
- pc += thumb_insn_size (inst1);
- itstate = thumb_advance_itstate (itstate);
- }
+ return 0;
+}
- return MAKE_THUMB_ADDR (pc);
- }
- else if ((itstate & 0x0f) == 0x08)
- {
- /* This is the last instruction of the conditional
- block, and it is executed. We can handle it normally
- because the following instruction is not conditional,
- and we must handle it normally because it is
- permitted to branch. Fall through. */
- }
- else
- {
- int cond_negated;
+static int
+thumb2_copy_copro_load_store (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn1, 0, 3);
- /* There are conditional instructions after this one.
- If this instruction modifies the flags, then we can
- not predict what the next executed instruction will
- be. Fortunately, this instruction is architecturally
- forbidden to branch; we know it will fall through.
- Start by skipping past it. */
- pc += thumb_insn_size (inst1);
- itstate = thumb_advance_itstate (itstate);
+ if (rn != ARM_PC_REGNUM)
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "copro load/store", dsc);
- /* Set a breakpoint on the following instruction. */
- gdb_assert ((itstate & 0x0f) != 0);
- if (insert_bkpt)
- insert_single_step_breakpoint (gdbarch, aspace, pc);
- cond_negated = (itstate >> 4) & 1;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying coprocessor "
+ "load/store insn %.4x%.4x\n", insn1, insn2);
- /* Skip all following instructions with the same
- condition. If there is a later instruction in the IT
- block with the opposite condition, set the other
- breakpoint there. If not, then set a breakpoint on
- the instruction after the IT block. */
- do
- {
- inst1 = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
- pc += thumb_insn_size (inst1);
- itstate = thumb_advance_itstate (itstate);
- }
- while (itstate != 0 && ((itstate >> 4) & 1) == cond_negated);
+ dsc->modinsn[0] = insn1 & 0xfff0;
+ dsc->modinsn[1] = insn2;
+ dsc->numinsns = 2;
- return MAKE_THUMB_ADDR (pc);
- }
- }
- }
- else if (itstate & 0x0f)
- {
- /* We are in a conditional block. Check the condition. */
- int cond = itstate >> 4;
+ /* This function is called for copying instruction LDC/LDC2/VLDR, which
+ doesn't support writeback, so pass 0. */
+ install_copro_load_store (gdbarch, regs, dsc, 0, rn);
- if (! condition_true (cond, status))
- {
- /* Advance to the next instruction. All the 32-bit
- instructions share a common prefix. */
- if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0)
- return MAKE_THUMB_ADDR (pc + 4);
- else
- return MAKE_THUMB_ADDR (pc + 2);
- }
+ return 0;
+}
- /* Otherwise, handle the instruction normally. */
- }
+/* Clean up branch instructions (actually perform the branch, by setting
+ PC). */
- if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */
- {
- CORE_ADDR sp;
+static void
+cleanup_branch (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
+ int branch_taken = condition_true (dsc->u.branch.cond, status);
+ enum pc_write_style write_pc = dsc->u.branch.exchange
+ ? BX_WRITE_PC : BRANCH_WRITE_PC;
- /* Fetch the saved PC from the stack. It's stored above
- all of the other registers. */
- offset = bitcount (bits (inst1, 0, 7)) * INT_REGISTER_SIZE;
- sp = get_frame_register_unsigned (frame, ARM_SP_REGNUM);
- nextpc = read_memory_unsigned_integer (sp + offset, 4, byte_order);
- }
- else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
- {
- unsigned long cond = bits (inst1, 8, 11);
- if (cond != 0x0f && condition_true (cond, status)) /* 0x0f = SWI */
- nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
- }
- else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */
- {
- nextpc = pc_val + (sbits (inst1, 0, 10) << 1);
- }
- else if ((inst1 & 0xe000) == 0xe000) /* 32-bit instruction */
+ if (!branch_taken)
+ return;
+
+ if (dsc->u.branch.link)
{
- unsigned short inst2;
- inst2 = read_memory_unsigned_integer (pc + 2, 2, byte_order_for_code);
+ /* The value of LR should be the next insn of current one. In order
+ not to confuse logic hanlding later insn `bx lr', if current insn mode
+ is Thumb, the bit 0 of LR value should be set to 1. */
+ ULONGEST next_insn_addr = dsc->insn_addr + dsc->insn_size;
- /* Default to the next instruction. */
- nextpc = pc + 4;
- nextpc = MAKE_THUMB_ADDR (nextpc);
+ if (dsc->is_thumb)
+ next_insn_addr |= 0x1;
- if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000)
- {
- /* Branches and miscellaneous control instructions. */
+ displaced_write_reg (regs, dsc, ARM_LR_REGNUM, next_insn_addr,
+ CANNOT_WRITE_PC);
+ }
- if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000)
- {
- /* B, BL, BLX. */
- int j1, j2, imm1, imm2;
+ displaced_write_reg (regs, dsc, ARM_PC_REGNUM, dsc->u.branch.dest, write_pc);
+}
- imm1 = sbits (inst1, 0, 10);
- imm2 = bits (inst2, 0, 10);
- j1 = bit (inst2, 13);
- j2 = bit (inst2, 11);
+/* Copy B/BL/BLX instructions with immediate destinations. */
- offset = ((imm1 << 12) + (imm2 << 1));
- offset ^= ((!j2) << 22) | ((!j1) << 23);
+static void
+install_b_bl_blx (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc,
+ unsigned int cond, int exchange, int link, long offset)
+{
+ /* Implement "BL<cond> <label>" as:
+
+ Preparation: cond <- instruction condition
+ Insn: mov r0, r0 (nop)
+ Cleanup: if (condition true) { r14 <- pc; pc <- label }.
- nextpc = pc_val + offset;
- /* For BLX make sure to clear the low bits. */
- if (bit (inst2, 12) == 0)
- nextpc = nextpc & 0xfffffffc;
- }
- else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00)
- {
- /* SUBS PC, LR, #imm8. */
- nextpc = get_frame_register_unsigned (frame, ARM_LR_REGNUM);
- nextpc -= inst2 & 0x00ff;
- }
- else if ((inst2 & 0xd000) == 0x8000 && (inst1 & 0x0380) != 0x0380)
- {
- /* Conditional branch. */
- if (condition_true (bits (inst1, 6, 9), status))
- {
- int sign, j1, j2, imm1, imm2;
+ B<cond> similar, but don't set r14 in cleanup. */
- sign = sbits (inst1, 10, 10);
- imm1 = bits (inst1, 0, 5);
- imm2 = bits (inst2, 0, 10);
- j1 = bit (inst2, 13);
- j2 = bit (inst2, 11);
+ dsc->u.branch.cond = cond;
+ dsc->u.branch.link = link;
+ dsc->u.branch.exchange = exchange;
- offset = (sign << 20) + (j2 << 19) + (j1 << 18);
- offset += (imm1 << 12) + (imm2 << 1);
+ dsc->u.branch.dest = dsc->insn_addr;
+ if (link && exchange)
+ /* For BLX, offset is computed from the Align (PC, 4). */
+ dsc->u.branch.dest = dsc->u.branch.dest & 0xfffffffc;
- nextpc = pc_val + offset;
- }
- }
- }
- else if ((inst1 & 0xfe50) == 0xe810)
- {
- /* Load multiple or RFE. */
- int rn, offset, load_pc = 1;
+ if (dsc->is_thumb)
+ dsc->u.branch.dest += 4 + offset;
+ else
+ dsc->u.branch.dest += 8 + offset;
- rn = bits (inst1, 0, 3);
- if (bit (inst1, 7) && !bit (inst1, 8))
- {
- /* LDMIA or POP */
- if (!bit (inst2, 15))
- load_pc = 0;
- offset = bitcount (inst2) * 4 - 4;
- }
- else if (!bit (inst1, 7) && bit (inst1, 8))
- {
- /* LDMDB */
- if (!bit (inst2, 15))
- load_pc = 0;
- offset = -4;
- }
- else if (bit (inst1, 7) && bit (inst1, 8))
- {
- /* RFEIA */
- offset = 0;
- }
- else if (!bit (inst1, 7) && !bit (inst1, 8))
- {
- /* RFEDB */
- offset = -8;
- }
- else
- load_pc = 0;
+ dsc->cleanup = &cleanup_branch;
+}
+static int
+arm_copy_b_bl_blx (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int cond = bits (insn, 28, 31);
+ int exchange = (cond == 0xf);
+ int link = exchange || bit (insn, 24);
+ long offset;
- if (load_pc)
- {
- CORE_ADDR addr = get_frame_register_unsigned (frame, rn);
- nextpc = get_frame_memory_unsigned (frame, addr + offset, 4);
- }
- }
- else if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00)
- {
- /* MOV PC or MOVS PC. */
- nextpc = get_frame_register_unsigned (frame, bits (inst2, 0, 3));
- nextpc = MAKE_THUMB_ADDR (nextpc);
- }
- else if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000)
- {
- /* LDR PC. */
- CORE_ADDR base;
- int rn, load_pc = 1;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s immediate insn "
+ "%.8lx\n", (exchange) ? "blx" : (link) ? "bl" : "b",
+ (unsigned long) insn);
+ if (exchange)
+ /* For BLX, set bit 0 of the destination. The cleanup_branch function will
+ then arrange the switch into Thumb mode. */
+ offset = (bits (insn, 0, 23) << 2) | (bit (insn, 24) << 1) | 1;
+ else
+ offset = bits (insn, 0, 23) << 2;
- rn = bits (inst1, 0, 3);
- base = get_frame_register_unsigned (frame, rn);
- if (rn == 15)
- {
- base = (base + 4) & ~(CORE_ADDR) 0x3;
- if (bit (inst1, 7))
- base += bits (inst2, 0, 11);
- else
- base -= bits (inst2, 0, 11);
- }
- else if (bit (inst1, 7))
- base += bits (inst2, 0, 11);
- else if (bit (inst2, 11))
- {
- if (bit (inst2, 10))
- {
- if (bit (inst2, 9))
- base += bits (inst2, 0, 7);
- else
- base -= bits (inst2, 0, 7);
- }
- }
- else if ((inst2 & 0x0fc0) == 0x0000)
- {
- int shift = bits (inst2, 4, 5), rm = bits (inst2, 0, 3);
- base += get_frame_register_unsigned (frame, rm) << shift;
- }
- else
- /* Reserved. */
- load_pc = 0;
+ if (bit (offset, 25))
+ offset = offset | ~0x3ffffff;
- if (load_pc)
- nextpc = get_frame_memory_unsigned (frame, base, 4);
- }
- else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000)
- {
- /* TBB. */
- CORE_ADDR tbl_reg, table, offset, length;
+ dsc->modinsn[0] = ARM_NOP;
- tbl_reg = bits (inst1, 0, 3);
- if (tbl_reg == 0x0f)
- table = pc + 4; /* Regcache copy of PC isn't right yet. */
- else
- table = get_frame_register_unsigned (frame, tbl_reg);
+ install_b_bl_blx (gdbarch, regs, dsc, cond, exchange, link, offset);
+ return 0;
+}
- offset = get_frame_register_unsigned (frame, bits (inst2, 0, 3));
- length = 2 * get_frame_memory_unsigned (frame, table + offset, 1);
- nextpc = pc_val + length;
+static int
+thumb2_copy_b_bl_blx (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ int link = bit (insn2, 14);
+ int exchange = link && !bit (insn2, 12);
+ int cond = INST_AL;
+ long offset = 0;
+ int j1 = bit (insn2, 13);
+ int j2 = bit (insn2, 11);
+ int s = sbits (insn1, 10, 10);
+ int i1 = !(j1 ^ bit (insn1, 10));
+ int i2 = !(j2 ^ bit (insn1, 10));
+
+ if (!link && !exchange) /* B */
+ {
+ offset = (bits (insn2, 0, 10) << 1);
+ if (bit (insn2, 12)) /* Encoding T4 */
+ {
+ offset |= (bits (insn1, 0, 9) << 12)
+ | (i2 << 22)
+ | (i1 << 23)
+ | (s << 24);
+ cond = INST_AL;
}
- else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf010)
+ else /* Encoding T3 */
{
- /* TBH. */
- CORE_ADDR tbl_reg, table, offset, length;
-
- tbl_reg = bits (inst1, 0, 3);
- if (tbl_reg == 0x0f)
- table = pc + 4; /* Regcache copy of PC isn't right yet. */
- else
- table = get_frame_register_unsigned (frame, tbl_reg);
-
- offset = 2 * get_frame_register_unsigned (frame, bits (inst2, 0, 3));
- length = 2 * get_frame_memory_unsigned (frame, table + offset, 2);
- nextpc = pc_val + length;
+ offset |= (bits (insn1, 0, 5) << 12)
+ | (j1 << 18)
+ | (j2 << 19)
+ | (s << 20);
+ cond = bits (insn1, 6, 9);
}
}
- else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
+ else
{
- if (bits (inst1, 3, 6) == 0x0f)
- nextpc = pc_val;
- else
- nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6));
+ offset = (bits (insn1, 0, 9) << 12);
+ offset |= ((i2 << 22) | (i1 << 23) | (s << 24));
+ offset |= exchange ?
+ (bits (insn2, 1, 10) << 2) : (bits (insn2, 0, 10) << 1);
}
- else if ((inst1 & 0xf500) == 0xb100)
- {
- /* CBNZ or CBZ. */
- int imm = (bit (inst1, 9) << 6) + (bits (inst1, 3, 7) << 1);
- ULONGEST reg = get_frame_register_unsigned (frame, bits (inst1, 0, 2));
- if (bit (inst1, 11) && reg != 0)
- nextpc = pc_val + imm;
- else if (!bit (inst1, 11) && reg == 0)
- nextpc = pc_val + imm;
- }
- return nextpc;
-}
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s insn "
+ "%.4x %.4x with offset %.8lx\n",
+ link ? (exchange) ? "blx" : "bl" : "b",
+ insn1, insn2, offset);
-/* Get the raw next address. PC is the current program counter, in
- FRAME. INSERT_BKPT should be TRUE if we want a breakpoint set on
- the alternative next instruction if there are two options.
+ dsc->modinsn[0] = THUMB_NOP;
- The value returned has the execution state of the next instruction
- encoded in it. Use IS_THUMB_ADDR () to see whether the instruction is
- in Thumb-State, and gdbarch_addr_bits_remove () to get the plain memory
- address.
-*/
-static CORE_ADDR
-arm_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt)
+ install_b_bl_blx (gdbarch, regs, dsc, cond, exchange, link, offset);
+ return 0;
+}
+
+/* Copy B Thumb instructions. */
+static int
+thumb_copy_b (struct gdbarch *gdbarch, unsigned short insn,
+ struct displaced_step_closure *dsc)
{
- struct gdbarch *gdbarch = get_frame_arch (frame);
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
- unsigned long pc_val;
- unsigned long this_instr;
- unsigned long status;
- CORE_ADDR nextpc;
+ unsigned int cond = 0;
+ int offset = 0;
+ unsigned short bit_12_15 = bits (insn, 12, 15);
+ CORE_ADDR from = dsc->insn_addr;
- if (arm_frame_is_thumb (frame))
- return thumb_get_next_pc_raw (frame, pc, insert_bkpt);
+ if (bit_12_15 == 0xd)
+ {
+ /* offset = SignExtend (imm8:0, 32) */
+ offset = sbits ((insn << 1), 0, 8);
+ cond = bits (insn, 8, 11);
+ }
+ else if (bit_12_15 == 0xe) /* Encoding T2 */
+ {
+ offset = sbits ((insn << 1), 0, 11);
+ cond = INST_AL;
+ }
- pc_val = (unsigned long) pc;
- this_instr = read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying b immediate insn %.4x "
+ "with offset %d\n", insn, offset);
- status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
- nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
+ dsc->u.branch.cond = cond;
+ dsc->u.branch.link = 0;
+ dsc->u.branch.exchange = 0;
+ dsc->u.branch.dest = from + 4 + offset;
- if (bits (this_instr, 28, 31) == INST_NV)
- switch (bits (this_instr, 24, 27))
- {
- case 0xa:
- case 0xb:
- {
- /* Branch with Link and change to Thumb. */
- nextpc = BranchDest (pc, this_instr);
- nextpc |= bit (this_instr, 24) << 1;
- nextpc = MAKE_THUMB_ADDR (nextpc);
- break;
- }
- case 0xc:
- case 0xd:
- case 0xe:
- /* Coprocessor register transfer. */
- if (bits (this_instr, 12, 15) == 15)
- error (_("Invalid update to pc in instruction"));
- break;
- }
- else if (condition_true (bits (this_instr, 28, 31), status))
- {
- switch (bits (this_instr, 24, 27))
- {
- case 0x0:
- case 0x1: /* data processing */
- case 0x2:
- case 0x3:
- {
- unsigned long operand1, operand2, result = 0;
- unsigned long rn;
- int c;
+ dsc->modinsn[0] = THUMB_NOP;
- if (bits (this_instr, 12, 15) != 15)
- break;
+ dsc->cleanup = &cleanup_branch;
- if (bits (this_instr, 22, 25) == 0
- && bits (this_instr, 4, 7) == 9) /* multiply */
- error (_("Invalid update to pc in instruction"));
+ return 0;
+}
+
+/* Copy BX/BLX with register-specified destinations. */
- /* BX <reg>, BLX <reg> */
- if (bits (this_instr, 4, 27) == 0x12fff1
- || bits (this_instr, 4, 27) == 0x12fff3)
- {
- rn = bits (this_instr, 0, 3);
- nextpc = (rn == 15) ? pc_val + 8
- : get_frame_register_unsigned (frame, rn);
- return nextpc;
- }
+static void
+install_bx_blx_reg (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc, int link,
+ unsigned int cond, unsigned int rm)
+{
+ /* Implement {BX,BLX}<cond> <reg>" as:
- /* Multiply into PC */
- c = (status & FLAG_C) ? 1 : 0;
- rn = bits (this_instr, 16, 19);
- operand1 = (rn == 15) ? pc_val + 8
- : get_frame_register_unsigned (frame, rn);
+ Preparation: cond <- instruction condition
+ Insn: mov r0, r0 (nop)
+ Cleanup: if (condition true) { r14 <- pc; pc <- dest; }.
- if (bit (this_instr, 25))
- {
- unsigned long immval = bits (this_instr, 0, 7);
- unsigned long rotate = 2 * bits (this_instr, 8, 11);
- operand2 = ((immval >> rotate) | (immval << (32 - rotate)))
- & 0xffffffff;
- }
- else /* operand 2 is a shifted register */
- operand2 = shifted_reg_val (frame, this_instr, c, pc_val, status);
+ Don't set r14 in cleanup for BX. */
- switch (bits (this_instr, 21, 24))
- {
- case 0x0: /*and */
- result = operand1 & operand2;
- break;
+ dsc->u.branch.dest = displaced_read_reg (regs, dsc, rm);
- case 0x1: /*eor */
- result = operand1 ^ operand2;
- break;
+ dsc->u.branch.cond = cond;
+ dsc->u.branch.link = link;
- case 0x2: /*sub */
- result = operand1 - operand2;
- break;
+ dsc->u.branch.exchange = 1;
- case 0x3: /*rsb */
- result = operand2 - operand1;
- break;
+ dsc->cleanup = &cleanup_branch;
+}
- case 0x4: /*add */
- result = operand1 + operand2;
- break;
+static int
+arm_copy_bx_blx_reg (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int cond = bits (insn, 28, 31);
+ /* BX: x12xxx1x
+ BLX: x12xxx3x. */
+ int link = bit (insn, 5);
+ unsigned int rm = bits (insn, 0, 3);
- case 0x5: /*adc */
- result = operand1 + operand2 + c;
- break;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.8lx",
+ (unsigned long) insn);
- case 0x6: /*sbc */
- result = operand1 - operand2 + c;
- break;
+ dsc->modinsn[0] = ARM_NOP;
- case 0x7: /*rsc */
- result = operand2 - operand1 + c;
- break;
+ install_bx_blx_reg (gdbarch, regs, dsc, link, cond, rm);
+ return 0;
+}
- case 0x8:
- case 0x9:
- case 0xa:
- case 0xb: /* tst, teq, cmp, cmn */
- result = (unsigned long) nextpc;
- break;
+static int
+thumb_copy_bx_blx_reg (struct gdbarch *gdbarch, uint16_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ int link = bit (insn, 7);
+ unsigned int rm = bits (insn, 3, 6);
- case 0xc: /*orr */
- result = operand1 | operand2;
- break;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.4x",
+ (unsigned short) insn);
- case 0xd: /*mov */
- /* Always step into a function. */
- result = operand2;
- break;
+ dsc->modinsn[0] = THUMB_NOP;
- case 0xe: /*bic */
- result = operand1 & ~operand2;
- break;
+ install_bx_blx_reg (gdbarch, regs, dsc, link, INST_AL, rm);
- case 0xf: /*mvn */
- result = ~operand2;
- break;
- }
+ return 0;
+}
- /* In 26-bit APCS the bottom two bits of the result are
- ignored, and we always end up in ARM state. */
- if (!arm_apcs_32)
- nextpc = arm_addr_bits_remove (gdbarch, result);
- else
- nextpc = result;
- break;
- }
+/* Copy/cleanup arithmetic/logic instruction with immediate RHS. */
- case 0x4:
- case 0x5: /* data transfer */
- case 0x6:
- case 0x7:
- if (bit (this_instr, 20))
- {
- /* load */
- if (bits (this_instr, 12, 15) == 15)
- {
- /* rd == pc */
- unsigned long rn;
- unsigned long base;
+static void
+cleanup_alu_imm (struct gdbarch *gdbarch,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ ULONGEST rd_val = displaced_read_reg (regs, dsc, 0);
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
- if (bit (this_instr, 22))
- error (_("Invalid update to pc in instruction"));
+static int
+arm_copy_alu_imm (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rd = bits (insn, 12, 15);
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd);
+ ULONGEST rd_val, rn_val;
- /* byte write to PC */
- rn = bits (this_instr, 16, 19);
- base = (rn == 15) ? pc_val + 8
- : get_frame_register_unsigned (frame, rn);
- if (bit (this_instr, 24))
- {
- /* pre-indexed */
- int c = (status & FLAG_C) ? 1 : 0;
- unsigned long offset =
- (bit (this_instr, 25)
- ? shifted_reg_val (frame, this_instr, c, pc_val, status)
- : bits (this_instr, 0, 11));
+ if (!insn_references_pc (insn, 0x000ff000ul))
+ return arm_copy_unmodified (gdbarch, insn, "ALU immediate", dsc);
- if (bit (this_instr, 23))
- base += offset;
- else
- base -= offset;
- }
- nextpc = (CORE_ADDR) read_memory_integer ((CORE_ADDR) base,
- 4, byte_order);
- }
- }
- break;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying immediate %s insn "
+ "%.8lx\n", is_mov ? "move" : "ALU",
+ (unsigned long) insn);
- case 0x8:
- case 0x9: /* block transfer */
- if (bit (this_instr, 20))
- {
- /* LDM */
- if (bit (this_instr, 15))
- {
- /* loading pc */
- int offset = 0;
+ /* Instruction is of form:
- if (bit (this_instr, 23))
- {
- /* up */
- unsigned long reglist = bits (this_instr, 0, 14);
- offset = bitcount (reglist) * 4;
- if (bit (this_instr, 24)) /* pre */
- offset += 4;
- }
- else if (bit (this_instr, 24))
- offset = -4;
+ <op><cond> rd, [rn,] #imm
- {
- unsigned long rn_val =
- get_frame_register_unsigned (frame,
- bits (this_instr, 16, 19));
- nextpc =
- (CORE_ADDR) read_memory_integer ((CORE_ADDR) (rn_val
- + offset),
- 4, byte_order);
- }
- }
- }
- break;
+ Rewrite as:
- case 0xb: /* branch & link */
- case 0xa: /* branch */
- {
- nextpc = BranchDest (pc, this_instr);
- break;
- }
+ Preparation: tmp1, tmp2 <- r0, r1;
+ r0, r1 <- rd, rn
+ Insn: <op><cond> r0, r1, #imm
+ Cleanup: rd <- r0; r0 <- tmp1; r1 <- tmp2
+ */
- case 0xc:
- case 0xd:
- case 0xe: /* coproc ops */
- case 0xf: /* SWI */
- break;
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rd_val = displaced_read_reg (regs, dsc, rd);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
- default:
- fprintf_filtered (gdb_stderr, _("Bad bit-field extraction\n"));
- return (pc);
- }
- }
+ if (is_mov)
+ dsc->modinsn[0] = insn & 0xfff00fff;
+ else
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x10000;
- return nextpc;
+ dsc->cleanup = &cleanup_alu_imm;
+
+ return 0;
}
-CORE_ADDR
-arm_get_next_pc (struct frame_info *frame, CORE_ADDR pc)
+static int
+thumb2_copy_alu_imm (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- struct gdbarch *gdbarch = get_frame_arch (frame);
- CORE_ADDR nextpc =
- gdbarch_addr_bits_remove (gdbarch,
- arm_get_next_pc_raw (frame, pc, TRUE));
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- return nextpc;
-}
+ unsigned int op = bits (insn1, 5, 8);
+ unsigned int rn, rm, rd;
+ ULONGEST rd_val, rn_val;
-/* single_step() is called just before we want to resume the inferior,
- if we want to single-step it but there is no hardware or kernel
- single-step support. We find the target of the coming instruction
- and breakpoint it. */
+ rn = bits (insn1, 0, 3); /* Rn */
+ rm = bits (insn2, 0, 3); /* Rm */
+ rd = bits (insn2, 8, 11); /* Rd */
-int
-arm_software_single_step (struct frame_info *frame)
-{
- struct gdbarch *gdbarch = get_frame_arch (frame);
- struct address_space *aspace = get_frame_address_space (frame);
+ /* This routine is only called for instruction MOV. */
+ gdb_assert (op == 0x2 && rn == 0xf);
- /* NOTE: This may insert the wrong breakpoint instruction when
- single-stepping over a mode-changing instruction, if the
- CPSR heuristics are used. */
+ if (rm != ARM_PC_REGNUM && rd != ARM_PC_REGNUM)
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2, "ALU imm", dsc);
- CORE_ADDR next_pc = arm_get_next_pc (frame, get_frame_pc (frame));
- insert_single_step_breakpoint (gdbarch, aspace, next_pc);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying reg %s insn %.4x%.4x\n",
+ "ALU", insn1, insn2);
- return 1;
+ /* Instruction is of form:
+
+ <op><cond> rd, [rn,] #imm
+
+ Rewrite as:
+
+ Preparation: tmp1, tmp2 <- r0, r1;
+ r0, r1 <- rd, rn
+ Insn: <op><cond> r0, r1, #imm
+ Cleanup: rd <- r0; r0 <- tmp1; r1 <- tmp2
+ */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rd_val = displaced_read_reg (regs, dsc, rd);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
+
+ dsc->modinsn[0] = insn1;
+ dsc->modinsn[1] = ((insn2 & 0xf0f0) | 0x1);
+ dsc->numinsns = 2;
+
+ dsc->cleanup = &cleanup_alu_imm;
+
+ return 0;
}
-/* Given BUF, which is OLD_LEN bytes ending at ENDADDR, expand
- the buffer to be NEW_LEN bytes ending at ENDADDR. Return
- NULL if an error occurs. BUF is freed. */
+/* Copy/cleanup arithmetic/logic insns with register RHS. */
-static gdb_byte *
-extend_buffer_earlier (gdb_byte *buf, CORE_ADDR endaddr,
- int old_len, int new_len)
+static void
+cleanup_alu_reg (struct gdbarch *gdbarch,
+ struct regcache *regs, struct displaced_step_closure *dsc)
{
- gdb_byte *new_buf, *middle;
- int bytes_to_read = new_len - old_len;
+ ULONGEST rd_val;
+ int i;
- new_buf = xmalloc (new_len);
- memcpy (new_buf + bytes_to_read, buf, old_len);
- xfree (buf);
- if (target_read_memory (endaddr - new_len, new_buf, bytes_to_read) != 0)
- {
- xfree (new_buf);
- return NULL;
- }
- return new_buf;
-}
+ rd_val = displaced_read_reg (regs, dsc, 0);
-/* An IT block is at most the 2-byte IT instruction followed by
- four 4-byte instructions. The furthest back we must search to
- find an IT block that affects the current instruction is thus
- 2 + 3 * 4 == 14 bytes. */
-#define MAX_IT_BLOCK_PREFIX 14
+ for (i = 0; i < 3; i++)
+ displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC);
-/* Use a quick scan if there are more than this many bytes of
- code. */
-#define IT_SCAN_THRESHOLD 32
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
-/* Adjust a breakpoint's address to move breakpoints out of IT blocks.
- A breakpoint in an IT block may not be hit, depending on the
- condition flags. */
-static CORE_ADDR
-arm_adjust_breakpoint_address (struct gdbarch *gdbarch, CORE_ADDR bpaddr)
+static void
+install_alu_reg (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc,
+ unsigned int rd, unsigned int rn, unsigned int rm)
{
- gdb_byte *buf;
- char map_type;
- CORE_ADDR boundary, func_start;
- int buf_len, buf2_len;
- enum bfd_endian order = gdbarch_byte_order_for_code (gdbarch);
- int i, any, last_it, last_it_count;
-
- /* If we are using BKPT breakpoints, none of this is necessary. */
- if (gdbarch_tdep (gdbarch)->thumb2_breakpoint == NULL)
- return bpaddr;
+ ULONGEST rd_val, rn_val, rm_val;
- /* ARM mode does not have this problem. */
- if (!arm_pc_is_thumb (bpaddr))
- return bpaddr;
+ /* Instruction is of form:
- /* We are setting a breakpoint in Thumb code that could potentially
- contain an IT block. The first step is to find how much Thumb
- code there is; we do not need to read outside of known Thumb
- sequences. */
- map_type = arm_find_mapping_symbol (bpaddr, &boundary);
- if (map_type == 0)
- /* Thumb-2 code must have mapping symbols to have a chance. */
- return bpaddr;
+ <op><cond> rd, [rn,] rm [, <shift>]
- bpaddr = gdbarch_addr_bits_remove (gdbarch, bpaddr);
+ Rewrite as:
- if (find_pc_partial_function (bpaddr, NULL, &func_start, NULL)
- && func_start > boundary)
- boundary = func_start;
+ Preparation: tmp1, tmp2, tmp3 <- r0, r1, r2;
+ r0, r1, r2 <- rd, rn, rm
+ Insn: <op><cond> r0, r1, r2 [, <shift>]
+ Cleanup: rd <- r0; r0, r1, r2 <- tmp1, tmp2, tmp3
+ */
- /* Search for a candidate IT instruction. We have to do some fancy
- footwork to distinguish a real IT instruction from the second
- half of a 32-bit instruction, but there is no need for that if
- there's no candidate. */
- buf_len = min (bpaddr - boundary, MAX_IT_BLOCK_PREFIX);
- if (buf_len == 0)
- /* No room for an IT instruction. */
- return bpaddr;
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ dsc->tmp[2] = displaced_read_reg (regs, dsc, 2);
+ rd_val = displaced_read_reg (regs, dsc, rd);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rm_val = displaced_read_reg (regs, dsc, rm);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
- buf = xmalloc (buf_len);
- if (target_read_memory (bpaddr - buf_len, buf, buf_len) != 0)
- return bpaddr;
- any = 0;
- for (i = 0; i < buf_len; i += 2)
- {
- unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
- if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
- {
- any = 1;
- break;
- }
- }
- if (any == 0)
- {
- xfree (buf);
- return bpaddr;
- }
+ dsc->cleanup = &cleanup_alu_reg;
+}
- /* OK, the code bytes before this instruction contain at least one
- halfword which resembles an IT instruction. We know that it's
- Thumb code, but there are still two possibilities. Either the
- halfword really is an IT instruction, or it is the second half of
- a 32-bit Thumb instruction. The only way we can tell is to
- scan forwards from a known instruction boundary. */
- if (bpaddr - boundary > IT_SCAN_THRESHOLD)
- {
- int definite;
+static int
+arm_copy_alu_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd);
- /* There's a lot of code before this instruction. Start with an
- optimistic search; it's easy to recognize halfwords that can
- not be the start of a 32-bit instruction, and use that to
- lock on to the instruction boundaries. */
- buf = extend_buffer_earlier (buf, bpaddr, buf_len, IT_SCAN_THRESHOLD);
- if (buf == NULL)
- return bpaddr;
- buf_len = IT_SCAN_THRESHOLD;
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return arm_copy_unmodified (gdbarch, insn, "ALU reg", dsc);
- definite = 0;
- for (i = 0; i < buf_len - sizeof (buf) && ! definite; i += 2)
- {
- unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
- if (thumb_insn_size (inst1) == 2)
- {
- definite = 1;
- break;
- }
- }
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying reg %s insn %.8lx\n",
+ is_mov ? "move" : "ALU", (unsigned long) insn);
- /* At this point, if DEFINITE, BUF[I] is the first place we
- are sure that we know the instruction boundaries, and it is far
- enough from BPADDR that we could not miss an IT instruction
- affecting BPADDR. If ! DEFINITE, give up - start from a
- known boundary. */
- if (! definite)
- {
- buf = extend_buffer_earlier (buf, bpaddr, buf_len, bpaddr - boundary);
- if (buf == NULL)
- return bpaddr;
- buf_len = bpaddr - boundary;
- i = 0;
- }
- }
+ if (is_mov)
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x2;
else
- {
- buf = extend_buffer_earlier (buf, bpaddr, buf_len, bpaddr - boundary);
- if (buf == NULL)
- return bpaddr;
- buf_len = bpaddr - boundary;
- i = 0;
- }
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x10002;
- /* Scan forwards. Find the last IT instruction before BPADDR. */
- last_it = -1;
- last_it_count = 0;
- while (i < buf_len)
- {
- unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
- last_it_count--;
- if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
- {
- last_it = i;
- if (inst1 & 0x0001)
- last_it_count = 4;
- else if (inst1 & 0x0002)
- last_it_count = 3;
- else if (inst1 & 0x0004)
- last_it_count = 2;
- else
- last_it_count = 1;
- }
- i += thumb_insn_size (inst1);
- }
+ install_alu_reg (gdbarch, regs, dsc, bits (insn, 12, 15), bits (insn, 16, 19),
+ bits (insn, 0, 3));
+ return 0;
+}
- xfree (buf);
+static int
+thumb_copy_alu_reg (struct gdbarch *gdbarch, uint16_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned rn, rm, rd;
- if (last_it == -1)
- /* There wasn't really an IT instruction after all. */
- return bpaddr;
+ rd = bits (insn, 3, 6);
+ rn = (bit (insn, 7) << 3) | bits (insn, 0, 2);
+ rm = 2;
- if (last_it_count < 1)
- /* It was too far away. */
- return bpaddr;
+ if (rd != ARM_PC_REGNUM && rn != ARM_PC_REGNUM)
+ return thumb_copy_unmodified_16bit (gdbarch, insn, "ALU reg", dsc);
- /* This really is a trouble spot. Move the breakpoint to the IT
- instruction. */
- return bpaddr - buf_len + last_it;
-}
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying reg %s insn %.4x\n",
+ "ALU", (unsigned short) insn);
-/* ARM displaced stepping support.
+ dsc->modinsn[0] = ((insn & 0xff00) | 0x08);
- Generally ARM displaced stepping works as follows:
+ install_alu_reg (gdbarch, regs, dsc, rd, rn, rm);
- 1. When an instruction is to be single-stepped, it is first decoded by
- arm_process_displaced_insn (called from arm_displaced_step_copy_insn).
- Depending on the type of instruction, it is then copied to a scratch
- location, possibly in a modified form. The copy_* set of functions
- performs such modification, as necessary. A breakpoint is placed after
- the modified instruction in the scratch space to return control to GDB.
- Note in particular that instructions which modify the PC will no longer
- do so after modification.
+ return 0;
+}
- 2. The instruction is single-stepped, by setting the PC to the scratch
- location address, and resuming. Control returns to GDB when the
- breakpoint is hit.
+/* Cleanup/copy arithmetic/logic insns with shifted register RHS. */
- 3. A cleanup function (cleanup_*) is called corresponding to the copy_*
- function used for the current instruction. This function's job is to
- put the CPU/memory state back to what it would have been if the
- instruction had been executed unmodified in its original location. */
+static void
+cleanup_alu_shifted_reg (struct gdbarch *gdbarch,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST rd_val = displaced_read_reg (regs, dsc, 0);
+ int i;
-/* NOP instruction (mov r0, r0). */
-#define ARM_NOP 0xe1a00000
+ for (i = 0; i < 4; i++)
+ displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC);
-/* Helper for register reads for displaced stepping. In particular, this
- returns the PC as it would be seen by the instruction at its original
- location. */
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
-ULONGEST
-displaced_read_reg (struct regcache *regs, CORE_ADDR from, int regno)
+static void
+install_alu_shifted_reg (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc,
+ unsigned int rd, unsigned int rn, unsigned int rm,
+ unsigned rs)
{
- ULONGEST ret;
+ int i;
+ ULONGEST rd_val, rn_val, rm_val, rs_val;
- if (regno == 15)
- {
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: read pc value %.8lx\n",
- (unsigned long) from + 8);
- return (ULONGEST) from + 8; /* Pipeline offset. */
- }
- else
- {
- regcache_cooked_read_unsigned (regs, regno, &ret);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: read r%d value %.8lx\n",
- regno, (unsigned long) ret);
- return ret;
- }
+ /* Instruction is of form:
+
+ <op><cond> rd, [rn,] rm, <shift> rs
+
+ Rewrite as:
+
+ Preparation: tmp1, tmp2, tmp3, tmp4 <- r0, r1, r2, r3
+ r0, r1, r2, r3 <- rd, rn, rm, rs
+ Insn: <op><cond> r0, r1, r2, <shift> r3
+ Cleanup: tmp5 <- r0
+ r0, r1, r2, r3 <- tmp1, tmp2, tmp3, tmp4
+ rd <- tmp5
+ */
+
+ for (i = 0; i < 4; i++)
+ dsc->tmp[i] = displaced_read_reg (regs, dsc, i);
+
+ rd_val = displaced_read_reg (regs, dsc, rd);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rm_val = displaced_read_reg (regs, dsc, rm);
+ rs_val = displaced_read_reg (regs, dsc, rs);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 3, rs_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
+ dsc->cleanup = &cleanup_alu_shifted_reg;
}
static int
-displaced_in_arm_mode (struct regcache *regs)
+arm_copy_alu_shifted_reg (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- ULONGEST ps;
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd);
+ unsigned int rd, rn, rm, rs;
- regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps);
+ if (!insn_references_pc (insn, 0x000fff0ful))
+ return arm_copy_unmodified (gdbarch, insn, "ALU shifted reg", dsc);
- return (ps & CPSR_T) == 0;
-}
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying shifted reg %s insn "
+ "%.8lx\n", is_mov ? "move" : "ALU",
+ (unsigned long) insn);
-/* Write to the PC as from a branch instruction. */
+ rn = bits (insn, 16, 19);
+ rm = bits (insn, 0, 3);
+ rs = bits (insn, 8, 11);
+ rd = bits (insn, 12, 15);
-static void
-branch_write_pc (struct regcache *regs, ULONGEST val)
-{
- if (displaced_in_arm_mode (regs))
- /* Note: If bits 0/1 are set, this branch would be unpredictable for
- architecture versions < 6. */
- regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & ~(ULONGEST) 0x3);
+ if (is_mov)
+ dsc->modinsn[0] = (insn & 0xfff000f0) | 0x302;
else
- regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & ~(ULONGEST) 0x1);
+ dsc->modinsn[0] = (insn & 0xfff000f0) | 0x10302;
+
+ install_alu_shifted_reg (gdbarch, regs, dsc, rd, rn, rm, rs);
+
+ return 0;
}
-/* Write to the PC as from a branch-exchange instruction. */
+/* Clean up load instructions. */
static void
-bx_write_pc (struct regcache *regs, ULONGEST val)
+cleanup_load (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- ULONGEST ps;
+ ULONGEST rt_val, rt_val2 = 0, rn_val;
- regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps);
+ rt_val = displaced_read_reg (regs, dsc, 0);
+ if (dsc->u.ldst.xfersize == 8)
+ rt_val2 = displaced_read_reg (regs, dsc, 1);
+ rn_val = displaced_read_reg (regs, dsc, 2);
- if ((val & 1) == 1)
- {
- regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps | CPSR_T);
- regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffe);
- }
- else if ((val & 2) == 0)
- {
- regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM,
- ps & ~(ULONGEST) CPSR_T);
- regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val);
- }
- else
- {
- /* Unpredictable behaviour. Try to do something sensible (switch to ARM
- mode, align dest to 4 bytes). */
- warning (_("Single-stepping BX to non-word-aligned ARM instruction."));
- regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM,
- ps & ~(ULONGEST) CPSR_T);
- regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffc);
- }
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (dsc->u.ldst.xfersize > 4)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.immed)
+ displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC);
+
+ /* Handle register writeback. */
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC);
+ /* Put result in right place. */
+ displaced_write_reg (regs, dsc, dsc->rd, rt_val, LOAD_WRITE_PC);
+ if (dsc->u.ldst.xfersize == 8)
+ displaced_write_reg (regs, dsc, dsc->rd + 1, rt_val2, LOAD_WRITE_PC);
}
-/* Write to the PC as if from a load instruction. */
+/* Clean up store instructions. */
static void
-load_write_pc (struct regcache *regs, ULONGEST val)
+cleanup_store (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- if (DISPLACED_STEPPING_ARCH_VERSION >= 5)
- bx_write_pc (regs, val);
- else
- branch_write_pc (regs, val);
-}
+ ULONGEST rn_val = displaced_read_reg (regs, dsc, 2);
-/* Write to the PC as if from an ALU instruction. */
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (dsc->u.ldst.xfersize > 4)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.immed)
+ displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.restore_r4)
+ displaced_write_reg (regs, dsc, 4, dsc->tmp[4], CANNOT_WRITE_PC);
-static void
-alu_write_pc (struct regcache *regs, ULONGEST val)
-{
- if (DISPLACED_STEPPING_ARCH_VERSION >= 7 && displaced_in_arm_mode (regs))
- bx_write_pc (regs, val);
- else
- branch_write_pc (regs, val);
+ /* Writeback. */
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC);
}
-/* Helper for writing to registers for displaced stepping. Writing to the PC
- has a varying effects depending on the instruction which does the write:
- this is controlled by the WRITE_PC argument. */
+/* Copy "extra" load/store instructions. These are halfword/doubleword
+ transfers, which have a different encoding to byte/word transfers. */
-void
-displaced_write_reg (struct regcache *regs, struct displaced_step_closure *dsc,
- int regno, ULONGEST val, enum pc_write_style write_pc)
+static int
+arm_copy_extra_ld_st (struct gdbarch *gdbarch, uint32_t insn, int unpriveleged,
+ struct regcache *regs, struct displaced_step_closure *dsc)
{
- if (regno == 15)
- {
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: writing pc %.8lx\n",
- (unsigned long) val);
- switch (write_pc)
- {
- case BRANCH_WRITE_PC:
- branch_write_pc (regs, val);
- break;
+ unsigned int op1 = bits (insn, 20, 24);
+ unsigned int op2 = bits (insn, 5, 6);
+ unsigned int rt = bits (insn, 12, 15);
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ char load[12] = {0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1};
+ char bytesize[12] = {2, 2, 2, 2, 8, 1, 8, 1, 8, 2, 8, 2};
+ int immed = (op1 & 0x4) != 0;
+ int opcode;
+ ULONGEST rt_val, rt_val2 = 0, rn_val, rm_val = 0;
- case BX_WRITE_PC:
- bx_write_pc (regs, val);
- break;
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return arm_copy_unmodified (gdbarch, insn, "extra load/store", dsc);
- case LOAD_WRITE_PC:
- load_write_pc (regs, val);
- break;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %sextra load/store "
+ "insn %.8lx\n", unpriveleged ? "unpriveleged " : "",
+ (unsigned long) insn);
- case ALU_WRITE_PC:
- alu_write_pc (regs, val);
- break;
+ opcode = ((op2 << 2) | (op1 & 0x1) | ((op1 & 0x4) >> 1)) - 4;
- case CANNOT_WRITE_PC:
- warning (_("Instruction wrote to PC in an unexpected way when "
- "single-stepping"));
- break;
+ if (opcode < 0)
+ internal_error (__FILE__, __LINE__,
+ _("copy_extra_ld_st: instruction decode error"));
- default:
- internal_error (__FILE__, __LINE__,
- _("Invalid argument to displaced_write_reg"));
- }
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ dsc->tmp[2] = displaced_read_reg (regs, dsc, 2);
+ if (!immed)
+ dsc->tmp[3] = displaced_read_reg (regs, dsc, 3);
- dsc->wrote_to_pc = 1;
- }
+ rt_val = displaced_read_reg (regs, dsc, rt);
+ if (bytesize[opcode] == 8)
+ rt_val2 = displaced_read_reg (regs, dsc, rt + 1);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ if (!immed)
+ rm_val = displaced_read_reg (regs, dsc, rm);
+
+ displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC);
+ if (bytesize[opcode] == 8)
+ displaced_write_reg (regs, dsc, 1, rt_val2, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC);
+ if (!immed)
+ displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC);
+
+ dsc->rd = rt;
+ dsc->u.ldst.xfersize = bytesize[opcode];
+ dsc->u.ldst.rn = rn;
+ dsc->u.ldst.immed = immed;
+ dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0;
+ dsc->u.ldst.restore_r4 = 0;
+
+ if (immed)
+ /* {ldr,str}<width><cond> rt, [rt2,] [rn, #imm]
+ ->
+ {ldr,str}<width><cond> r0, [r1,] [r2, #imm]. */
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000;
else
- {
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: writing r%d value %.8lx\n",
- regno, (unsigned long) val);
- regcache_cooked_write_unsigned (regs, regno, val);
- }
+ /* {ldr,str}<width><cond> rt, [rt2,] [rn, +/-rm]
+ ->
+ {ldr,str}<width><cond> r0, [r1,] [r2, +/-r3]. */
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003;
+
+ dsc->cleanup = load[opcode] ? &cleanup_load : &cleanup_store;
+
+ return 0;
}
-/* This function is used to concisely determine if an instruction INSN
- references PC. Register fields of interest in INSN should have the
- corresponding fields of BITMASK set to 0b1111. The function returns return 1
- if any of these fields in INSN reference the PC (also 0b1111, r15), else it
- returns 0. */
+/* Copy byte/half word/word loads and stores. */
-static int
-insn_references_pc (uint32_t insn, uint32_t bitmask)
+static void
+install_load_store (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc, int load,
+ int immed, int writeback, int size, int usermode,
+ int rt, int rm, int rn)
{
- uint32_t lowbit = 1;
+ ULONGEST rt_val, rn_val, rm_val = 0;
- while (bitmask != 0)
- {
- uint32_t mask;
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[2] = displaced_read_reg (regs, dsc, 2);
+ if (!immed)
+ dsc->tmp[3] = displaced_read_reg (regs, dsc, 3);
+ if (!load)
+ dsc->tmp[4] = displaced_read_reg (regs, dsc, 4);
- for (; lowbit && (bitmask & lowbit) == 0; lowbit <<= 1)
- ;
+ rt_val = displaced_read_reg (regs, dsc, rt);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ if (!immed)
+ rm_val = displaced_read_reg (regs, dsc, rm);
- if (!lowbit)
- break;
+ displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC);
+ if (!immed)
+ displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC);
+ dsc->rd = rt;
+ dsc->u.ldst.xfersize = size;
+ dsc->u.ldst.rn = rn;
+ dsc->u.ldst.immed = immed;
+ dsc->u.ldst.writeback = writeback;
- mask = lowbit * 0xf;
+ /* To write PC we can do:
- if ((insn & mask) == mask)
- return 1;
+ Before this sequence of instructions:
+ r0 is the PC value got from displaced_read_reg, so r0 = from + 8;
+ r2 is the Rn value got from dispalced_read_reg.
- bitmask &= ~mask;
- }
+ Insn1: push {pc} Write address of STR instruction + offset on stack
+ Insn2: pop {r4} Read it back from stack, r4 = addr(Insn1) + offset
+ Insn3: sub r4, r4, pc r4 = addr(Insn1) + offset - pc
+ = addr(Insn1) + offset - addr(Insn3) - 8
+ = offset - 16
+ Insn4: add r4, r4, #8 r4 = offset - 8
+ Insn5: add r0, r0, r4 r0 = from + 8 + offset - 8
+ = from + offset
+ Insn6: str r0, [r2, #imm] (or str r0, [r2, r3])
- return 0;
+ Otherwise we don't know what value to write for PC, since the offset is
+ architecture-dependent (sometimes PC+8, sometimes PC+12). More details
+ of this can be found in Section "Saving from r15" in
+ http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0204g/Cihbjifh.html */
+
+ dsc->cleanup = load ? &cleanup_load : &cleanup_store;
}
-/* The simplest copy function. Many instructions have the same effect no
- matter what address they are executed at: in those cases, use this. */
static int
-copy_unmodified (struct gdbarch *gdbarch, uint32_t insn,
- const char *iname, struct displaced_step_closure *dsc)
+thumb2_copy_load_literal (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc, int size)
{
+ unsigned int u_bit = bit (insn1, 7);
+ unsigned int rt = bits (insn2, 12, 15);
+ int imm12 = bits (insn2, 0, 11);
+ ULONGEST pc_val;
+
if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.8lx, "
- "opcode/class '%s' unmodified\n", (unsigned long) insn,
- iname);
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying ldr pc (0x%x) R%d %c imm12 %.4x\n",
+ (unsigned int) dsc->insn_addr, rt, u_bit ? '+' : '-',
+ imm12);
- dsc->modinsn[0] = insn;
+ if (!u_bit)
+ imm12 = -1 * imm12;
- return 0;
-}
+ /* Rewrite instruction LDR Rt imm12 into:
-/* Preload instructions with immediate offset. */
+ Prepare: tmp[0] <- r0, tmp[1] <- r2, tmp[2] <- r3, r2 <- pc, r3 <- imm12
-static void
-cleanup_preload (struct gdbarch *gdbarch,
- struct regcache *regs, struct displaced_step_closure *dsc)
-{
- displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
- if (!dsc->u.preload.immed)
- displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ LDR R0, R2, R3,
+
+ Cleanup: rt <- r0, r0 <- tmp[0], r2 <- tmp[1], r3 <- tmp[2]. */
+
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[2] = displaced_read_reg (regs, dsc, 2);
+ dsc->tmp[3] = displaced_read_reg (regs, dsc, 3);
+
+ pc_val = displaced_read_reg (regs, dsc, ARM_PC_REGNUM);
+
+ pc_val = pc_val & 0xfffffffc;
+
+ displaced_write_reg (regs, dsc, 2, pc_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 3, imm12, CANNOT_WRITE_PC);
+
+ dsc->rd = rt;
+
+ dsc->u.ldst.xfersize = size;
+ dsc->u.ldst.immed = 0;
+ dsc->u.ldst.writeback = 0;
+ dsc->u.ldst.restore_r4 = 0;
+
+ /* LDR R0, R2, R3 */
+ dsc->modinsn[0] = 0xf852;
+ dsc->modinsn[1] = 0x3;
+ dsc->numinsns = 2;
+
+ dsc->cleanup = &cleanup_load;
+
+ return 0;
}
static int
-copy_preload (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
- struct displaced_step_closure *dsc)
+thumb2_copy_load_reg_imm (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc,
+ int writeback, int immed)
{
- unsigned int rn = bits (insn, 16, 19);
- ULONGEST rn_val;
- CORE_ADDR from = dsc->insn_addr;
+ unsigned int rt = bits (insn2, 12, 15);
+ unsigned int rn = bits (insn1, 0, 3);
+ unsigned int rm = bits (insn2, 0, 3); /* Only valid if !immed. */
+ /* In LDR (register), there is also a register Rm, which is not allowed to
+ be PC, so we don't have to check it. */
- if (!insn_references_pc (insn, 0x000f0000ul))
- return copy_unmodified (gdbarch, insn, "preload", dsc);
+ if (rt != ARM_PC_REGNUM && rn != ARM_PC_REGNUM)
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2, "load",
+ dsc);
if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n",
- (unsigned long) insn);
-
- /* Preload instructions:
-
- {pli/pld} [rn, #+/-imm]
- ->
- {pli/pld} [r0, #+/-imm]. */
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying ldr r%d [r%d] insn %.4x%.4x\n",
+ rt, rn, insn1, insn2);
- dsc->tmp[0] = displaced_read_reg (regs, from, 0);
- rn_val = displaced_read_reg (regs, from, rn);
- displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+ install_load_store (gdbarch, regs, dsc, 1, immed, writeback, 4,
+ 0, rt, rm, rn);
- dsc->u.preload.immed = 1;
+ dsc->u.ldst.restore_r4 = 0;
- dsc->modinsn[0] = insn & 0xfff0ffff;
+ if (immed)
+ /* ldr[b]<cond> rt, [rn, #imm], etc.
+ ->
+ ldr[b]<cond> r0, [r2, #imm]. */
+ {
+ dsc->modinsn[0] = (insn1 & 0xfff0) | 0x2;
+ dsc->modinsn[1] = insn2 & 0x0fff;
+ }
+ else
+ /* ldr[b]<cond> rt, [rn, rm], etc.
+ ->
+ ldr[b]<cond> r0, [r2, r3]. */
+ {
+ dsc->modinsn[0] = (insn1 & 0xfff0) | 0x2;
+ dsc->modinsn[1] = (insn2 & 0x0ff0) | 0x3;
+ }
- dsc->cleanup = &cleanup_preload;
+ dsc->numinsns = 2;
return 0;
}
-/* Preload instructions with register offset. */
static int
-copy_preload_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
- struct displaced_step_closure *dsc)
+arm_copy_ldr_str_ldrb_strb (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc,
+ int load, int size, int usermode)
{
+ int immed = !bit (insn, 25);
+ int writeback = (bit (insn, 24) == 0 || bit (insn, 21) != 0);
+ unsigned int rt = bits (insn, 12, 15);
unsigned int rn = bits (insn, 16, 19);
- unsigned int rm = bits (insn, 0, 3);
- ULONGEST rn_val, rm_val;
- CORE_ADDR from = dsc->insn_addr;
+ unsigned int rm = bits (insn, 0, 3); /* Only valid if !immed. */
- if (!insn_references_pc (insn, 0x000f000ful))
- return copy_unmodified (gdbarch, insn, "preload reg", dsc);
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return arm_copy_unmodified (gdbarch, insn, "load/store", dsc);
if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n",
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying %s%s r%d [r%d] insn %.8lx\n",
+ load ? (size == 1 ? "ldrb" : "ldr")
+ : (size == 1 ? "strb" : "str"), usermode ? "t" : "",
+ rt, rn,
(unsigned long) insn);
- /* Preload register-offset instructions:
+ install_load_store (gdbarch, regs, dsc, load, immed, writeback, size,
+ usermode, rt, rm, rn);
- {pli/pld} [rn, rm {, shift}]
- ->
- {pli/pld} [r0, r1 {, shift}]. */
+ if (load || rt != ARM_PC_REGNUM)
+ {
+ dsc->u.ldst.restore_r4 = 0;
- dsc->tmp[0] = displaced_read_reg (regs, from, 0);
- dsc->tmp[1] = displaced_read_reg (regs, from, 1);
- rn_val = displaced_read_reg (regs, from, rn);
- rm_val = displaced_read_reg (regs, from, rm);
- displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 1, rm_val, CANNOT_WRITE_PC);
+ if (immed)
+ /* {ldr,str}[b]<cond> rt, [rn, #imm], etc.
+ ->
+ {ldr,str}[b]<cond> r0, [r2, #imm]. */
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000;
+ else
+ /* {ldr,str}[b]<cond> rt, [rn, rm], etc.
+ ->
+ {ldr,str}[b]<cond> r0, [r2, r3]. */
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003;
+ }
+ else
+ {
+ /* We need to use r4 as scratch. Make sure it's restored afterwards. */
+ dsc->u.ldst.restore_r4 = 1;
+ dsc->modinsn[0] = 0xe92d8000; /* push {pc} */
+ dsc->modinsn[1] = 0xe8bd0010; /* pop {r4} */
+ dsc->modinsn[2] = 0xe044400f; /* sub r4, r4, pc. */
+ dsc->modinsn[3] = 0xe2844008; /* add r4, r4, #8. */
+ dsc->modinsn[4] = 0xe0800004; /* add r0, r0, r4. */
- dsc->u.preload.immed = 0;
+ /* As above. */
+ if (immed)
+ dsc->modinsn[5] = (insn & 0xfff00fff) | 0x20000;
+ else
+ dsc->modinsn[5] = (insn & 0xfff00ff0) | 0x20003;
- dsc->modinsn[0] = (insn & 0xfff0fff0) | 0x1;
+ dsc->numinsns = 6;
+ }
- dsc->cleanup = &cleanup_preload;
+ dsc->cleanup = load ? &cleanup_load : &cleanup_store;
return 0;
}
-/* Copy/cleanup coprocessor load and store instructions. */
+/* Cleanup LDM instructions with fully-populated register list. This is an
+ unfortunate corner case: it's impossible to implement correctly by modifying
+ the instruction. The issue is as follows: we have an instruction,
-static void
-cleanup_copro_load_store (struct gdbarch *gdbarch,
- struct regcache *regs,
- struct displaced_step_closure *dsc)
-{
- ULONGEST rn_val = displaced_read_reg (regs, dsc->insn_addr, 0);
+ ldm rN, {r0-r15}
- displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ which we must rewrite to avoid loading PC. A possible solution would be to
+ do the load in two halves, something like (with suitable cleanup
+ afterwards):
- if (dsc->u.ldst.writeback)
- displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, LOAD_WRITE_PC);
-}
+ mov r8, rN
+ ldm[id][ab] r8!, {r0-r7}
+ str r7, <temp>
+ ldm[id][ab] r8, {r7-r14}
+ <bkpt>
-static int
-copy_copro_load_store (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs,
- struct displaced_step_closure *dsc)
+ but at present there's no suitable place for <temp>, since the scratch space
+ is overwritten before the cleanup routine is called. For now, we simply
+ emulate the instruction. */
+
+static void
+cleanup_block_load_all (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned int rn = bits (insn, 16, 19);
- ULONGEST rn_val;
- CORE_ADDR from = dsc->insn_addr;
+ int inc = dsc->u.block.increment;
+ int bump_before = dsc->u.block.before ? (inc ? 4 : -4) : 0;
+ int bump_after = dsc->u.block.before ? 0 : (inc ? 4 : -4);
+ uint32_t regmask = dsc->u.block.regmask;
+ int regno = inc ? 0 : 15;
+ CORE_ADDR xfer_addr = dsc->u.block.xfer_addr;
+ int exception_return = dsc->u.block.load && dsc->u.block.user
+ && (regmask & 0x8000) != 0;
+ uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
+ int do_transfer = condition_true (dsc->u.block.cond, status);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- if (!insn_references_pc (insn, 0x000f0000ul))
- return copy_unmodified (gdbarch, insn, "copro load/store", dsc);
+ if (!do_transfer)
+ return;
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying coprocessor "
- "load/store insn %.8lx\n", (unsigned long) insn);
+ /* If the instruction is ldm rN, {...pc}^, I don't think there's anything
+ sensible we can do here. Complain loudly. */
+ if (exception_return)
+ error (_("Cannot single-step exception return"));
- /* Coprocessor load/store instructions:
+ /* We don't handle any stores here for now. */
+ gdb_assert (dsc->u.block.load != 0);
- {stc/stc2} [<Rn>, #+/-imm] (and other immediate addressing modes)
- ->
- {stc/stc2} [r0, #+/-imm].
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: emulating block transfer: "
+ "%s %s %s\n", dsc->u.block.load ? "ldm" : "stm",
+ dsc->u.block.increment ? "inc" : "dec",
+ dsc->u.block.before ? "before" : "after");
- ldc/ldc2 are handled identically. */
+ while (regmask)
+ {
+ uint32_t memword;
- dsc->tmp[0] = displaced_read_reg (regs, from, 0);
- rn_val = displaced_read_reg (regs, from, rn);
- displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+ if (inc)
+ while (regno <= ARM_PC_REGNUM && (regmask & (1 << regno)) == 0)
+ regno++;
+ else
+ while (regno >= 0 && (regmask & (1 << regno)) == 0)
+ regno--;
- dsc->u.ldst.writeback = bit (insn, 25);
- dsc->u.ldst.rn = rn;
+ xfer_addr += bump_before;
- dsc->modinsn[0] = insn & 0xfff0ffff;
+ memword = read_memory_unsigned_integer (xfer_addr, 4, byte_order);
+ displaced_write_reg (regs, dsc, regno, memword, LOAD_WRITE_PC);
- dsc->cleanup = &cleanup_copro_load_store;
+ xfer_addr += bump_after;
- return 0;
+ regmask &= ~(1 << regno);
+ }
+
+ if (dsc->u.block.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.block.rn, xfer_addr,
+ CANNOT_WRITE_PC);
}
-/* Clean up branch instructions (actually perform the branch, by setting
- PC). */
+/* Clean up an STM which included the PC in the register list. */
static void
-cleanup_branch (struct gdbarch *gdbarch, struct regcache *regs,
- struct displaced_step_closure *dsc)
+cleanup_block_store_pc (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- ULONGEST from = dsc->insn_addr;
- uint32_t status = displaced_read_reg (regs, from, ARM_PS_REGNUM);
- int branch_taken = condition_true (dsc->u.branch.cond, status);
- enum pc_write_style write_pc = dsc->u.branch.exchange
- ? BX_WRITE_PC : BRANCH_WRITE_PC;
+ uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
+ int store_executed = condition_true (dsc->u.block.cond, status);
+ CORE_ADDR pc_stored_at, transferred_regs = bitcount (dsc->u.block.regmask);
+ CORE_ADDR stm_insn_addr;
+ uint32_t pc_val;
+ long offset;
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- if (!branch_taken)
+ /* If condition code fails, there's nothing else to do. */
+ if (!store_executed)
return;
- if (dsc->u.branch.link)
+ if (dsc->u.block.increment)
+ {
+ pc_stored_at = dsc->u.block.xfer_addr + 4 * transferred_regs;
+
+ if (dsc->u.block.before)
+ pc_stored_at += 4;
+ }
+ else
{
- ULONGEST pc = displaced_read_reg (regs, from, 15);
- displaced_write_reg (regs, dsc, 14, pc - 4, CANNOT_WRITE_PC);
+ pc_stored_at = dsc->u.block.xfer_addr;
+
+ if (dsc->u.block.before)
+ pc_stored_at -= 4;
}
- displaced_write_reg (regs, dsc, 15, dsc->u.branch.dest, write_pc);
+ pc_val = read_memory_unsigned_integer (pc_stored_at, 4, byte_order);
+ stm_insn_addr = dsc->scratch_base;
+ offset = pc_val - stm_insn_addr;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: detected PC offset %.8lx for "
+ "STM instruction\n", offset);
+
+ /* Rewrite the stored PC to the proper value for the non-displaced original
+ instruction. */
+ write_memory_unsigned_integer (pc_stored_at, 4, byte_order,
+ dsc->insn_addr + offset);
}
-/* Copy B/BL/BLX instructions with immediate destinations. */
+/* Clean up an LDM which includes the PC in the register list. We clumped all
+ the registers in the transferred list into a contiguous range r0...rX (to
+ avoid loading PC directly and losing control of the debugged program), so we
+ must undo that here. */
-static int
-copy_b_bl_blx (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs, struct displaced_step_closure *dsc)
+static void
+cleanup_block_load_pc (struct gdbarch *gdbarch,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned int cond = bits (insn, 28, 31);
- int exchange = (cond == 0xf);
- int link = exchange || bit (insn, 24);
- CORE_ADDR from = dsc->insn_addr;
- long offset;
+ uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
+ int load_executed = condition_true (dsc->u.block.cond, status), i;
+ unsigned int mask = dsc->u.block.regmask, write_reg = ARM_PC_REGNUM;
+ unsigned int regs_loaded = bitcount (mask);
+ unsigned int num_to_shuffle = regs_loaded, clobbered;
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying %s immediate insn "
- "%.8lx\n", (exchange) ? "blx" : (link) ? "bl" : "b",
- (unsigned long) insn);
+ /* The method employed here will fail if the register list is fully populated
+ (we need to avoid loading PC directly). */
+ gdb_assert (num_to_shuffle < 16);
- /* Implement "BL<cond> <label>" as:
+ if (!load_executed)
+ return;
- Preparation: cond <- instruction condition
- Insn: mov r0, r0 (nop)
- Cleanup: if (condition true) { r14 <- pc; pc <- label }.
+ clobbered = (1 << num_to_shuffle) - 1;
+
+ while (num_to_shuffle > 0)
+ {
+ if ((mask & (1 << write_reg)) != 0)
+ {
+ unsigned int read_reg = num_to_shuffle - 1;
+
+ if (read_reg != write_reg)
+ {
+ ULONGEST rval = displaced_read_reg (regs, dsc, read_reg);
+ displaced_write_reg (regs, dsc, write_reg, rval, LOAD_WRITE_PC);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: move "
+ "loaded register r%d to r%d\n"), read_reg,
+ write_reg);
+ }
+ else if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: register "
+ "r%d already in the right place\n"),
+ write_reg);
- B<cond> similar, but don't set r14 in cleanup. */
+ clobbered &= ~(1 << write_reg);
- if (exchange)
- /* For BLX, set bit 0 of the destination. The cleanup_branch function will
- then arrange the switch into Thumb mode. */
- offset = (bits (insn, 0, 23) << 2) | (bit (insn, 24) << 1) | 1;
- else
- offset = bits (insn, 0, 23) << 2;
+ num_to_shuffle--;
+ }
- if (bit (offset, 25))
- offset = offset | ~0x3ffffff;
+ write_reg--;
+ }
- dsc->u.branch.cond = cond;
- dsc->u.branch.link = link;
- dsc->u.branch.exchange = exchange;
- dsc->u.branch.dest = from + 8 + offset;
+ /* Restore any registers we scribbled over. */
+ for (write_reg = 0; clobbered != 0; write_reg++)
+ {
+ if ((clobbered & (1 << write_reg)) != 0)
+ {
+ displaced_write_reg (regs, dsc, write_reg, dsc->tmp[write_reg],
+ CANNOT_WRITE_PC);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: restored "
+ "clobbered register r%d\n"), write_reg);
+ clobbered &= ~(1 << write_reg);
+ }
+ }
- dsc->modinsn[0] = ARM_NOP;
+ /* Perform register writeback manually. */
+ if (dsc->u.block.writeback)
+ {
+ ULONGEST new_rn_val = dsc->u.block.xfer_addr;
- dsc->cleanup = &cleanup_branch;
+ if (dsc->u.block.increment)
+ new_rn_val += regs_loaded * 4;
+ else
+ new_rn_val -= regs_loaded * 4;
- return 0;
+ displaced_write_reg (regs, dsc, dsc->u.block.rn, new_rn_val,
+ CANNOT_WRITE_PC);
+ }
}
-/* Copy BX/BLX with register-specified destinations. */
+/* Handle ldm/stm, apart from some tricky cases which are unlikely to occur
+ in user-level code (in particular exception return, ldm rn, {...pc}^). */
static int
-copy_bx_blx_reg (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs, struct displaced_step_closure *dsc)
+arm_copy_block_xfer (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned int cond = bits (insn, 28, 31);
- /* BX: x12xxx1x
- BLX: x12xxx3x. */
- int link = bit (insn, 5);
- unsigned int rm = bits (insn, 0, 3);
- CORE_ADDR from = dsc->insn_addr;
+ int load = bit (insn, 20);
+ int user = bit (insn, 22);
+ int increment = bit (insn, 23);
+ int before = bit (insn, 24);
+ int writeback = bit (insn, 21);
+ int rn = bits (insn, 16, 19);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying %s register insn "
- "%.8lx\n", (link) ? "blx" : "bx", (unsigned long) insn);
+ /* Block transfers which don't mention PC can be run directly
+ out-of-line. */
+ if (rn != ARM_PC_REGNUM && (insn & 0x8000) == 0)
+ return arm_copy_unmodified (gdbarch, insn, "ldm/stm", dsc);
- /* Implement {BX,BLX}<cond> <reg>" as:
+ if (rn == ARM_PC_REGNUM)
+ {
+ warning (_("displaced: Unpredictable LDM or STM with "
+ "base register r15"));
+ return arm_copy_unmodified (gdbarch, insn, "unpredictable ldm/stm", dsc);
+ }
- Preparation: cond <- instruction condition
- Insn: mov r0, r0 (nop)
- Cleanup: if (condition true) { r14 <- pc; pc <- dest; }.
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying block transfer insn "
+ "%.8lx\n", (unsigned long) insn);
- Don't set r14 in cleanup for BX. */
+ dsc->u.block.xfer_addr = displaced_read_reg (regs, dsc, rn);
+ dsc->u.block.rn = rn;
- dsc->u.branch.dest = displaced_read_reg (regs, from, rm);
+ dsc->u.block.load = load;
+ dsc->u.block.user = user;
+ dsc->u.block.increment = increment;
+ dsc->u.block.before = before;
+ dsc->u.block.writeback = writeback;
+ dsc->u.block.cond = bits (insn, 28, 31);
- dsc->u.branch.cond = cond;
- dsc->u.branch.link = link;
- dsc->u.branch.exchange = 1;
+ dsc->u.block.regmask = insn & 0xffff;
- dsc->modinsn[0] = ARM_NOP;
+ if (load)
+ {
+ if ((insn & 0xffff) == 0xffff)
+ {
+ /* LDM with a fully-populated register list. This case is
+ particularly tricky. Implement for now by fully emulating the
+ instruction (which might not behave perfectly in all cases, but
+ these instructions should be rare enough for that not to matter
+ too much). */
+ dsc->modinsn[0] = ARM_NOP;
- dsc->cleanup = &cleanup_branch;
+ dsc->cleanup = &cleanup_block_load_all;
+ }
+ else
+ {
+ /* LDM of a list of registers which includes PC. Implement by
+ rewriting the list of registers to be transferred into a
+ contiguous chunk r0...rX before doing the transfer, then shuffling
+ registers into the correct places in the cleanup routine. */
+ unsigned int regmask = insn & 0xffff;
+ unsigned int num_in_list = bitcount (regmask), new_regmask, bit = 1;
+ unsigned int to = 0, from = 0, i, new_rn;
- return 0;
-}
+ for (i = 0; i < num_in_list; i++)
+ dsc->tmp[i] = displaced_read_reg (regs, dsc, i);
-/* Copy/cleanup arithmetic/logic instruction with immediate RHS. */
+ /* Writeback makes things complicated. We need to avoid clobbering
+ the base register with one of the registers in our modified
+ register list, but just using a different register can't work in
+ all cases, e.g.:
-static void
-cleanup_alu_imm (struct gdbarch *gdbarch,
- struct regcache *regs, struct displaced_step_closure *dsc)
-{
- ULONGEST rd_val = displaced_read_reg (regs, dsc->insn_addr, 0);
- displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
-}
+ ldm r14!, {r0-r13,pc}
-static int
-copy_alu_imm (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
- struct displaced_step_closure *dsc)
-{
- unsigned int rn = bits (insn, 16, 19);
- unsigned int rd = bits (insn, 12, 15);
- unsigned int op = bits (insn, 21, 24);
- int is_mov = (op == 0xd);
- ULONGEST rd_val, rn_val;
- CORE_ADDR from = dsc->insn_addr;
+ which would need to be rewritten as:
- if (!insn_references_pc (insn, 0x000ff000ul))
- return copy_unmodified (gdbarch, insn, "ALU immediate", dsc);
+ ldm rN!, {r0-r14}
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying immediate %s insn "
- "%.8lx\n", is_mov ? "move" : "ALU",
- (unsigned long) insn);
+ but that can't work, because there's no free register for N.
- /* Instruction is of form:
+ Solve this by turning off the writeback bit, and emulating
+ writeback manually in the cleanup routine. */
- <op><cond> rd, [rn,] #imm
+ if (writeback)
+ insn &= ~(1 << 21);
- Rewrite as:
+ new_regmask = (1 << num_in_list) - 1;
- Preparation: tmp1, tmp2 <- r0, r1;
- r0, r1 <- rd, rn
- Insn: <op><cond> r0, r1, #imm
- Cleanup: rd <- r0; r0 <- tmp1; r1 <- tmp2
- */
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM r%d%s, "
+ "{..., pc}: original reg list %.4x, modified "
+ "list %.4x\n"), rn, writeback ? "!" : "",
+ (int) insn & 0xffff, new_regmask);
- dsc->tmp[0] = displaced_read_reg (regs, from, 0);
- dsc->tmp[1] = displaced_read_reg (regs, from, 1);
- rn_val = displaced_read_reg (regs, from, rn);
- rd_val = displaced_read_reg (regs, from, rd);
- displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
- dsc->rd = rd;
+ dsc->modinsn[0] = (insn & ~0xffff) | (new_regmask & 0xffff);
- if (is_mov)
- dsc->modinsn[0] = insn & 0xfff00fff;
+ dsc->cleanup = &cleanup_block_load_pc;
+ }
+ }
else
- dsc->modinsn[0] = (insn & 0xfff00fff) | 0x10000;
+ {
+ /* STM of a list of registers which includes PC. Run the instruction
+ as-is, but out of line: this will store the wrong value for the PC,
+ so we must manually fix up the memory in the cleanup routine.
+ Doing things this way has the advantage that we can auto-detect
+ the offset of the PC write (which is architecture-dependent) in
+ the cleanup routine. */
+ dsc->modinsn[0] = insn;
- dsc->cleanup = &cleanup_alu_imm;
+ dsc->cleanup = &cleanup_block_store_pc;
+ }
return 0;
}
-/* Copy/cleanup arithmetic/logic insns with register RHS. */
-
-static void
-cleanup_alu_reg (struct gdbarch *gdbarch,
- struct regcache *regs, struct displaced_step_closure *dsc)
+static int
+thumb2_copy_block_xfer (struct gdbarch *gdbarch, uint16_t insn1, uint16_t insn2,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- ULONGEST rd_val;
- int i;
+ int rn = bits (insn1, 0, 3);
+ int load = bit (insn1, 4);
+ int writeback = bit (insn1, 5);
- rd_val = displaced_read_reg (regs, dsc->insn_addr, 0);
+ /* Block transfers which don't mention PC can be run directly
+ out-of-line. */
+ if (rn != ARM_PC_REGNUM && (insn2 & 0x8000) == 0)
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2, "ldm/stm", dsc);
- for (i = 0; i < 3; i++)
- displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC);
+ if (rn == ARM_PC_REGNUM)
+ {
+ warning (_("displaced: Unpredictable LDM or STM with "
+ "base register r15"));
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "unpredictable ldm/stm", dsc);
+ }
- displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
-}
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying block transfer insn "
+ "%.4x%.4x\n", insn1, insn2);
-static int
-copy_alu_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
- struct displaced_step_closure *dsc)
-{
- unsigned int rn = bits (insn, 16, 19);
- unsigned int rm = bits (insn, 0, 3);
- unsigned int rd = bits (insn, 12, 15);
- unsigned int op = bits (insn, 21, 24);
- int is_mov = (op == 0xd);
- ULONGEST rd_val, rn_val, rm_val;
- CORE_ADDR from = dsc->insn_addr;
+ /* Clear bit 13, since it should be always zero. */
+ dsc->u.block.regmask = (insn2 & 0xdfff);
+ dsc->u.block.rn = rn;
- if (!insn_references_pc (insn, 0x000ff00ful))
- return copy_unmodified (gdbarch, insn, "ALU reg", dsc);
+ dsc->u.block.load = load;
+ dsc->u.block.user = 0;
+ dsc->u.block.increment = bit (insn1, 7);
+ dsc->u.block.before = bit (insn1, 8);
+ dsc->u.block.writeback = writeback;
+ dsc->u.block.cond = INST_AL;
+ dsc->u.block.xfer_addr = displaced_read_reg (regs, dsc, rn);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying reg %s insn %.8lx\n",
- is_mov ? "move" : "ALU", (unsigned long) insn);
+ if (load)
+ {
+ if (dsc->u.block.regmask == 0xffff)
+ {
+ /* This branch is impossible to happen. */
+ gdb_assert (0);
+ }
+ else
+ {
+ unsigned int regmask = dsc->u.block.regmask;
+ unsigned int num_in_list = bitcount (regmask), new_regmask, bit = 1;
+ unsigned int to = 0, from = 0, i, new_rn;
- /* Instruction is of form:
+ for (i = 0; i < num_in_list; i++)
+ dsc->tmp[i] = displaced_read_reg (regs, dsc, i);
- <op><cond> rd, [rn,] rm [, <shift>]
+ if (writeback)
+ insn1 &= ~(1 << 5);
- Rewrite as:
+ new_regmask = (1 << num_in_list) - 1;
- Preparation: tmp1, tmp2, tmp3 <- r0, r1, r2;
- r0, r1, r2 <- rd, rn, rm
- Insn: <op><cond> r0, r1, r2 [, <shift>]
- Cleanup: rd <- r0; r0, r1, r2 <- tmp1, tmp2, tmp3
- */
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM r%d%s, "
+ "{..., pc}: original reg list %.4x, modified "
+ "list %.4x\n"), rn, writeback ? "!" : "",
+ (int) dsc->u.block.regmask, new_regmask);
- dsc->tmp[0] = displaced_read_reg (regs, from, 0);
- dsc->tmp[1] = displaced_read_reg (regs, from, 1);
- dsc->tmp[2] = displaced_read_reg (regs, from, 2);
- rd_val = displaced_read_reg (regs, from, rd);
- rn_val = displaced_read_reg (regs, from, rn);
- rm_val = displaced_read_reg (regs, from, rm);
- displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC);
- dsc->rd = rd;
+ dsc->modinsn[0] = insn1;
+ dsc->modinsn[1] = (new_regmask & 0xffff);
+ dsc->numinsns = 2;
- if (is_mov)
- dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x2;
+ dsc->cleanup = &cleanup_block_load_pc;
+ }
+ }
else
- dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x10002;
-
- dsc->cleanup = &cleanup_alu_reg;
-
+ {
+ dsc->modinsn[0] = insn1;
+ dsc->modinsn[1] = insn2;
+ dsc->numinsns = 2;
+ dsc->cleanup = &cleanup_block_store_pc;
+ }
return 0;
}
-/* Cleanup/copy arithmetic/logic insns with shifted register RHS. */
+/* Cleanup/copy SVC (SWI) instructions. These two functions are overridden
+ for Linux, where some SVC instructions must be treated specially. */
static void
-cleanup_alu_shifted_reg (struct gdbarch *gdbarch,
- struct regcache *regs,
- struct displaced_step_closure *dsc)
+cleanup_svc (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- ULONGEST rd_val = displaced_read_reg (regs, dsc->insn_addr, 0);
- int i;
+ CORE_ADDR resume_addr = dsc->insn_addr + dsc->insn_size;
- for (i = 0; i < 4; i++)
- displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: cleanup for svc, resume at "
+ "%.8lx\n", (unsigned long) resume_addr);
- displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+ displaced_write_reg (regs, dsc, ARM_PC_REGNUM, resume_addr, BRANCH_WRITE_PC);
}
+
+/* Common copy routine for svc instruciton. */
+
static int
-copy_alu_shifted_reg (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs, struct displaced_step_closure *dsc)
+install_svc (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned int rn = bits (insn, 16, 19);
- unsigned int rm = bits (insn, 0, 3);
- unsigned int rd = bits (insn, 12, 15);
- unsigned int rs = bits (insn, 8, 11);
- unsigned int op = bits (insn, 21, 24);
- int is_mov = (op == 0xd), i;
- ULONGEST rd_val, rn_val, rm_val, rs_val;
- CORE_ADDR from = dsc->insn_addr;
+ /* Preparation: none.
+ Insn: unmodified svc.
+ Cleanup: pc <- insn_addr + insn_size. */
- if (!insn_references_pc (insn, 0x000fff0ful))
- return copy_unmodified (gdbarch, insn, "ALU shifted reg", dsc);
+ /* Pretend we wrote to the PC, so cleanup doesn't set PC to the next
+ instruction. */
+ dsc->wrote_to_pc = 1;
+
+ /* Allow OS-specific code to override SVC handling. */
+ if (dsc->u.svc.copy_svc_os)
+ return dsc->u.svc.copy_svc_os (gdbarch, regs, dsc);
+ else
+ {
+ dsc->cleanup = &cleanup_svc;
+ return 0;
+ }
+}
+
+static int
+arm_copy_svc (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying shifted reg %s insn "
- "%.8lx\n", is_mov ? "move" : "ALU",
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying svc insn %.8lx\n",
(unsigned long) insn);
- /* Instruction is of form:
+ dsc->modinsn[0] = insn;
- <op><cond> rd, [rn,] rm, <shift> rs
+ return install_svc (gdbarch, regs, dsc);
+}
- Rewrite as:
+static int
+thumb_copy_svc (struct gdbarch *gdbarch, uint16_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
- Preparation: tmp1, tmp2, tmp3, tmp4 <- r0, r1, r2, r3
- r0, r1, r2, r3 <- rd, rn, rm, rs
- Insn: <op><cond> r0, r1, r2, <shift> r3
- Cleanup: tmp5 <- r0
- r0, r1, r2, r3 <- tmp1, tmp2, tmp3, tmp4
- rd <- tmp5
- */
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying svc insn %.4x\n",
+ insn);
- for (i = 0; i < 4; i++)
- dsc->tmp[i] = displaced_read_reg (regs, from, i);
+ dsc->modinsn[0] = insn;
- rd_val = displaced_read_reg (regs, from, rd);
- rn_val = displaced_read_reg (regs, from, rn);
- rm_val = displaced_read_reg (regs, from, rm);
- rs_val = displaced_read_reg (regs, from, rs);
- displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 3, rs_val, CANNOT_WRITE_PC);
- dsc->rd = rd;
+ return install_svc (gdbarch, regs, dsc);
+}
- if (is_mov)
- dsc->modinsn[0] = (insn & 0xfff000f0) | 0x302;
- else
- dsc->modinsn[0] = (insn & 0xfff000f0) | 0x10302;
+/* Copy undefined instructions. */
- dsc->cleanup = &cleanup_alu_shifted_reg;
+static int
+arm_copy_undef (struct gdbarch *gdbarch, uint32_t insn,
+ struct displaced_step_closure *dsc)
+{
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying undefined insn %.8lx\n",
+ (unsigned long) insn);
+
+ dsc->modinsn[0] = insn;
return 0;
}
-/* Clean up load instructions. */
-
-static void
-cleanup_load (struct gdbarch *gdbarch, struct regcache *regs,
- struct displaced_step_closure *dsc)
+static int
+thumb_32bit_copy_undef (struct gdbarch *gdbarch, uint16_t insn1, uint16_t insn2,
+ struct displaced_step_closure *dsc)
{
- ULONGEST rt_val, rt_val2 = 0, rn_val;
- CORE_ADDR from = dsc->insn_addr;
- rt_val = displaced_read_reg (regs, from, 0);
- if (dsc->u.ldst.xfersize == 8)
- rt_val2 = displaced_read_reg (regs, from, 1);
- rn_val = displaced_read_reg (regs, from, 2);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying undefined insn "
+ "%.4x %.4x\n", (unsigned short) insn1,
+ (unsigned short) insn2);
- displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
- if (dsc->u.ldst.xfersize > 4)
- displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC);
- if (!dsc->u.ldst.immed)
- displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC);
+ dsc->modinsn[0] = insn1;
+ dsc->modinsn[1] = insn2;
+ dsc->numinsns = 2;
- /* Handle register writeback. */
- if (dsc->u.ldst.writeback)
- displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC);
- /* Put result in right place. */
- displaced_write_reg (regs, dsc, dsc->rd, rt_val, LOAD_WRITE_PC);
- if (dsc->u.ldst.xfersize == 8)
- displaced_write_reg (regs, dsc, dsc->rd + 1, rt_val2, LOAD_WRITE_PC);
+ return 0;
}
-/* Clean up store instructions. */
+/* Copy unpredictable instructions. */
-static void
-cleanup_store (struct gdbarch *gdbarch, struct regcache *regs,
- struct displaced_step_closure *dsc)
+static int
+arm_copy_unpred (struct gdbarch *gdbarch, uint32_t insn,
+ struct displaced_step_closure *dsc)
{
- CORE_ADDR from = dsc->insn_addr;
- ULONGEST rn_val = displaced_read_reg (regs, from, 2);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying unpredictable insn "
+ "%.8lx\n", (unsigned long) insn);
- displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
- if (dsc->u.ldst.xfersize > 4)
- displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC);
- if (!dsc->u.ldst.immed)
- displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC);
- if (!dsc->u.ldst.restore_r4)
- displaced_write_reg (regs, dsc, 4, dsc->tmp[4], CANNOT_WRITE_PC);
+ dsc->modinsn[0] = insn;
- /* Writeback. */
- if (dsc->u.ldst.writeback)
- displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC);
+ return 0;
}
-/* Copy "extra" load/store instructions. These are halfword/doubleword
- transfers, which have a different encoding to byte/word transfers. */
+/* The decode_* functions are instruction decoding helpers. They mostly follow
+ the presentation in the ARM ARM. */
static int
-copy_extra_ld_st (struct gdbarch *gdbarch, uint32_t insn, int unpriveleged,
- struct regcache *regs, struct displaced_step_closure *dsc)
+arm_decode_misc_memhint_neon (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned int op1 = bits (insn, 20, 24);
- unsigned int op2 = bits (insn, 5, 6);
- unsigned int rt = bits (insn, 12, 15);
+ unsigned int op1 = bits (insn, 20, 26), op2 = bits (insn, 4, 7);
unsigned int rn = bits (insn, 16, 19);
- unsigned int rm = bits (insn, 0, 3);
- char load[12] = {0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1};
- char bytesize[12] = {2, 2, 2, 2, 8, 1, 8, 1, 8, 2, 8, 2};
- int immed = (op1 & 0x4) != 0;
- int opcode;
- ULONGEST rt_val, rt_val2 = 0, rn_val, rm_val = 0;
- CORE_ADDR from = dsc->insn_addr;
- if (!insn_references_pc (insn, 0x000ff00ful))
- return copy_unmodified (gdbarch, insn, "extra load/store", dsc);
-
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying %sextra load/store "
- "insn %.8lx\n", unpriveleged ? "unpriveleged " : "",
- (unsigned long) insn);
-
- opcode = ((op2 << 2) | (op1 & 0x1) | ((op1 & 0x4) >> 1)) - 4;
-
- if (opcode < 0)
- internal_error (__FILE__, __LINE__,
- _("copy_extra_ld_st: instruction decode error"));
-
- dsc->tmp[0] = displaced_read_reg (regs, from, 0);
- dsc->tmp[1] = displaced_read_reg (regs, from, 1);
- dsc->tmp[2] = displaced_read_reg (regs, from, 2);
- if (!immed)
- dsc->tmp[3] = displaced_read_reg (regs, from, 3);
+ if (op1 == 0x10 && (op2 & 0x2) == 0x0 && (rn & 0xe) == 0x0)
+ return arm_copy_unmodified (gdbarch, insn, "cps", dsc);
+ else if (op1 == 0x10 && op2 == 0x0 && (rn & 0xe) == 0x1)
+ return arm_copy_unmodified (gdbarch, insn, "setend", dsc);
+ else if ((op1 & 0x60) == 0x20)
+ return arm_copy_unmodified (gdbarch, insn, "neon dataproc", dsc);
+ else if ((op1 & 0x71) == 0x40)
+ return arm_copy_unmodified (gdbarch, insn, "neon elt/struct load/store",
+ dsc);
+ else if ((op1 & 0x77) == 0x41)
+ return arm_copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc);
+ else if ((op1 & 0x77) == 0x45)
+ return arm_copy_preload (gdbarch, insn, regs, dsc); /* pli. */
+ else if ((op1 & 0x77) == 0x51)
+ {
+ if (rn != 0xf)
+ return arm_copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */
+ else
+ return arm_copy_unpred (gdbarch, insn, dsc);
+ }
+ else if ((op1 & 0x77) == 0x55)
+ return arm_copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */
+ else if (op1 == 0x57)
+ switch (op2)
+ {
+ case 0x1: return arm_copy_unmodified (gdbarch, insn, "clrex", dsc);
+ case 0x4: return arm_copy_unmodified (gdbarch, insn, "dsb", dsc);
+ case 0x5: return arm_copy_unmodified (gdbarch, insn, "dmb", dsc);
+ case 0x6: return arm_copy_unmodified (gdbarch, insn, "isb", dsc);
+ default: return arm_copy_unpred (gdbarch, insn, dsc);
+ }
+ else if ((op1 & 0x63) == 0x43)
+ return arm_copy_unpred (gdbarch, insn, dsc);
+ else if ((op2 & 0x1) == 0x0)
+ switch (op1 & ~0x80)
+ {
+ case 0x61:
+ return arm_copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc);
+ case 0x65:
+ return arm_copy_preload_reg (gdbarch, insn, regs, dsc); /* pli reg. */
+ case 0x71: case 0x75:
+ /* pld/pldw reg. */
+ return arm_copy_preload_reg (gdbarch, insn, regs, dsc);
+ case 0x63: case 0x67: case 0x73: case 0x77:
+ return arm_copy_unpred (gdbarch, insn, dsc);
+ default:
+ return arm_copy_undef (gdbarch, insn, dsc);
+ }
+ else
+ return arm_copy_undef (gdbarch, insn, dsc); /* Probably unreachable. */
+}
- rt_val = displaced_read_reg (regs, from, rt);
- if (bytesize[opcode] == 8)
- rt_val2 = displaced_read_reg (regs, from, rt + 1);
- rn_val = displaced_read_reg (regs, from, rn);
- if (!immed)
- rm_val = displaced_read_reg (regs, from, rm);
+static int
+arm_decode_unconditional (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ if (bit (insn, 27) == 0)
+ return arm_decode_misc_memhint_neon (gdbarch, insn, regs, dsc);
+ /* Switch on bits: 0bxxxxx321xxx0xxxxxxxxxxxxxxxxxxxx. */
+ else switch (((insn & 0x7000000) >> 23) | ((insn & 0x100000) >> 20))
+ {
+ case 0x0: case 0x2:
+ return arm_copy_unmodified (gdbarch, insn, "srs", dsc);
- displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC);
- if (bytesize[opcode] == 8)
- displaced_write_reg (regs, dsc, 1, rt_val2, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC);
- if (!immed)
- displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC);
+ case 0x1: case 0x3:
+ return arm_copy_unmodified (gdbarch, insn, "rfe", dsc);
- dsc->rd = rt;
- dsc->u.ldst.xfersize = bytesize[opcode];
- dsc->u.ldst.rn = rn;
- dsc->u.ldst.immed = immed;
- dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0;
- dsc->u.ldst.restore_r4 = 0;
+ case 0x4: case 0x5: case 0x6: case 0x7:
+ return arm_copy_b_bl_blx (gdbarch, insn, regs, dsc);
- if (immed)
- /* {ldr,str}<width><cond> rt, [rt2,] [rn, #imm]
- ->
- {ldr,str}<width><cond> r0, [r1,] [r2, #imm]. */
- dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000;
- else
- /* {ldr,str}<width><cond> rt, [rt2,] [rn, +/-rm]
- ->
- {ldr,str}<width><cond> r0, [r1,] [r2, +/-r3]. */
- dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003;
+ case 0x8:
+ switch ((insn & 0xe00000) >> 21)
+ {
+ case 0x1: case 0x3: case 0x4: case 0x5: case 0x6: case 0x7:
+ /* stc/stc2. */
+ return arm_copy_copro_load_store (gdbarch, insn, regs, dsc);
- dsc->cleanup = load[opcode] ? &cleanup_load : &cleanup_store;
+ case 0x2:
+ return arm_copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc);
- return 0;
-}
+ default:
+ return arm_copy_undef (gdbarch, insn, dsc);
+ }
-/* Copy byte/word loads and stores. */
+ case 0x9:
+ {
+ int rn_f = (bits (insn, 16, 19) == 0xf);
+ switch ((insn & 0xe00000) >> 21)
+ {
+ case 0x1: case 0x3:
+ /* ldc/ldc2 imm (undefined for rn == pc). */
+ return rn_f ? arm_copy_undef (gdbarch, insn, dsc)
+ : arm_copy_copro_load_store (gdbarch, insn, regs, dsc);
-static int
-copy_ldr_str_ldrb_strb (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs,
- struct displaced_step_closure *dsc, int load, int byte,
- int usermode)
-{
- int immed = !bit (insn, 25);
- unsigned int rt = bits (insn, 12, 15);
- unsigned int rn = bits (insn, 16, 19);
- unsigned int rm = bits (insn, 0, 3); /* Only valid if !immed. */
- ULONGEST rt_val, rn_val, rm_val = 0;
- CORE_ADDR from = dsc->insn_addr;
+ case 0x2:
+ return arm_copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc);
- if (!insn_references_pc (insn, 0x000ff00ful))
- return copy_unmodified (gdbarch, insn, "load/store", dsc);
+ case 0x4: case 0x5: case 0x6: case 0x7:
+ /* ldc/ldc2 lit (undefined for rn != pc). */
+ return rn_f ? arm_copy_copro_load_store (gdbarch, insn, regs, dsc)
+ : arm_copy_undef (gdbarch, insn, dsc);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying %s%s insn %.8lx\n",
- load ? (byte ? "ldrb" : "ldr")
- : (byte ? "strb" : "str"), usermode ? "t" : "",
- (unsigned long) insn);
+ default:
+ return arm_copy_undef (gdbarch, insn, dsc);
+ }
+ }
- dsc->tmp[0] = displaced_read_reg (regs, from, 0);
- dsc->tmp[2] = displaced_read_reg (regs, from, 2);
- if (!immed)
- dsc->tmp[3] = displaced_read_reg (regs, from, 3);
- if (!load)
- dsc->tmp[4] = displaced_read_reg (regs, from, 4);
+ case 0xa:
+ return arm_copy_unmodified (gdbarch, insn, "stc/stc2", dsc);
- rt_val = displaced_read_reg (regs, from, rt);
- rn_val = displaced_read_reg (regs, from, rn);
- if (!immed)
- rm_val = displaced_read_reg (regs, from, rm);
+ case 0xb:
+ if (bits (insn, 16, 19) == 0xf)
+ /* ldc/ldc2 lit. */
+ return arm_copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else
+ return arm_copy_undef (gdbarch, insn, dsc);
- displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC);
- displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC);
- if (!immed)
- displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC);
+ case 0xc:
+ if (bit (insn, 4))
+ return arm_copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc);
+ else
+ return arm_copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
- dsc->rd = rt;
- dsc->u.ldst.xfersize = byte ? 1 : 4;
- dsc->u.ldst.rn = rn;
- dsc->u.ldst.immed = immed;
- dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0;
+ case 0xd:
+ if (bit (insn, 4))
+ return arm_copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc);
+ else
+ return arm_copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
- /* To write PC we can do:
+ default:
+ return arm_copy_undef (gdbarch, insn, dsc);
+ }
+}
- scratch+0: str pc, temp (*temp = scratch + 8 + offset)
- scratch+4: ldr r4, temp
- scratch+8: sub r4, r4, pc (r4 = scratch + 8 + offset - scratch - 8 - 8)
- scratch+12: add r4, r4, #8 (r4 = offset)
- scratch+16: add r0, r0, r4
- scratch+20: str r0, [r2, #imm] (or str r0, [r2, r3])
- scratch+24: <temp>
+/* Decode miscellaneous instructions in dp/misc encoding space. */
- Otherwise we don't know what value to write for PC, since the offset is
- architecture-dependent (sometimes PC+8, sometimes PC+12). */
+static int
+arm_decode_miscellaneous (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int op2 = bits (insn, 4, 6);
+ unsigned int op = bits (insn, 21, 22);
+ unsigned int op1 = bits (insn, 16, 19);
- if (load || rt != 15)
+ switch (op2)
{
- dsc->u.ldst.restore_r4 = 0;
+ case 0x0:
+ return arm_copy_unmodified (gdbarch, insn, "mrs/msr", dsc);
- if (immed)
- /* {ldr,str}[b]<cond> rt, [rn, #imm], etc.
- ->
- {ldr,str}[b]<cond> r0, [r2, #imm]. */
- dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000;
+ case 0x1:
+ if (op == 0x1) /* bx. */
+ return arm_copy_bx_blx_reg (gdbarch, insn, regs, dsc);
+ else if (op == 0x3)
+ return arm_copy_unmodified (gdbarch, insn, "clz", dsc);
else
- /* {ldr,str}[b]<cond> rt, [rn, rm], etc.
- ->
- {ldr,str}[b]<cond> r0, [r2, r3]. */
- dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003;
- }
- else
- {
- /* We need to use r4 as scratch. Make sure it's restored afterwards. */
- dsc->u.ldst.restore_r4 = 1;
-
- dsc->modinsn[0] = 0xe58ff014; /* str pc, [pc, #20]. */
- dsc->modinsn[1] = 0xe59f4010; /* ldr r4, [pc, #16]. */
- dsc->modinsn[2] = 0xe044400f; /* sub r4, r4, pc. */
- dsc->modinsn[3] = 0xe2844008; /* add r4, r4, #8. */
- dsc->modinsn[4] = 0xe0800004; /* add r0, r0, r4. */
+ return arm_copy_undef (gdbarch, insn, dsc);
- /* As above. */
- if (immed)
- dsc->modinsn[5] = (insn & 0xfff00fff) | 0x20000;
+ case 0x2:
+ if (op == 0x1)
+ /* Not really supported. */
+ return arm_copy_unmodified (gdbarch, insn, "bxj", dsc);
else
- dsc->modinsn[5] = (insn & 0xfff00ff0) | 0x20003;
+ return arm_copy_undef (gdbarch, insn, dsc);
- dsc->modinsn[6] = 0x0; /* breakpoint location. */
- dsc->modinsn[7] = 0x0; /* scratch space. */
+ case 0x3:
+ if (op == 0x1)
+ return arm_copy_bx_blx_reg (gdbarch, insn,
+ regs, dsc); /* blx register. */
+ else
+ return arm_copy_undef (gdbarch, insn, dsc);
- dsc->numinsns = 6;
- }
+ case 0x5:
+ return arm_copy_unmodified (gdbarch, insn, "saturating add/sub", dsc);
- dsc->cleanup = load ? &cleanup_load : &cleanup_store;
+ case 0x7:
+ if (op == 0x1)
+ return arm_copy_unmodified (gdbarch, insn, "bkpt", dsc);
+ else if (op == 0x3)
+ /* Not really supported. */
+ return arm_copy_unmodified (gdbarch, insn, "smc", dsc);
- return 0;
+ default:
+ return arm_copy_undef (gdbarch, insn, dsc);
+ }
}
-/* Cleanup LDM instructions with fully-populated register list. This is an
- unfortunate corner case: it's impossible to implement correctly by modifying
- the instruction. The issue is as follows: we have an instruction,
+static int
+arm_decode_dp_misc (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ if (bit (insn, 25))
+ switch (bits (insn, 20, 24))
+ {
+ case 0x10:
+ return arm_copy_unmodified (gdbarch, insn, "movw", dsc);
- ldm rN, {r0-r15}
+ case 0x14:
+ return arm_copy_unmodified (gdbarch, insn, "movt", dsc);
- which we must rewrite to avoid loading PC. A possible solution would be to
- do the load in two halves, something like (with suitable cleanup
- afterwards):
+ case 0x12: case 0x16:
+ return arm_copy_unmodified (gdbarch, insn, "msr imm", dsc);
- mov r8, rN
- ldm[id][ab] r8!, {r0-r7}
- str r7, <temp>
- ldm[id][ab] r8, {r7-r14}
- <bkpt>
+ default:
+ return arm_copy_alu_imm (gdbarch, insn, regs, dsc);
+ }
+ else
+ {
+ uint32_t op1 = bits (insn, 20, 24), op2 = bits (insn, 4, 7);
- but at present there's no suitable place for <temp>, since the scratch space
- is overwritten before the cleanup routine is called. For now, we simply
- emulate the instruction. */
+ if ((op1 & 0x19) != 0x10 && (op2 & 0x1) == 0x0)
+ return arm_copy_alu_reg (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) != 0x10 && (op2 & 0x9) == 0x1)
+ return arm_copy_alu_shifted_reg (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) == 0x10 && (op2 & 0x8) == 0x0)
+ return arm_decode_miscellaneous (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) == 0x10 && (op2 & 0x9) == 0x8)
+ return arm_copy_unmodified (gdbarch, insn, "halfword mul/mla", dsc);
+ else if ((op1 & 0x10) == 0x00 && op2 == 0x9)
+ return arm_copy_unmodified (gdbarch, insn, "mul/mla", dsc);
+ else if ((op1 & 0x10) == 0x10 && op2 == 0x9)
+ return arm_copy_unmodified (gdbarch, insn, "synch", dsc);
+ else if (op2 == 0xb || (op2 & 0xd) == 0xd)
+ /* 2nd arg means "unpriveleged". */
+ return arm_copy_extra_ld_st (gdbarch, insn, (op1 & 0x12) == 0x02, regs,
+ dsc);
+ }
-static void
-cleanup_block_load_all (struct gdbarch *gdbarch, struct regcache *regs,
- struct displaced_step_closure *dsc)
+ /* Should be unreachable. */
+ return 1;
+}
+
+static int
+arm_decode_ld_st_word_ubyte (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- ULONGEST from = dsc->insn_addr;
- int inc = dsc->u.block.increment;
- int bump_before = dsc->u.block.before ? (inc ? 4 : -4) : 0;
- int bump_after = dsc->u.block.before ? 0 : (inc ? 4 : -4);
- uint32_t regmask = dsc->u.block.regmask;
- int regno = inc ? 0 : 15;
- CORE_ADDR xfer_addr = dsc->u.block.xfer_addr;
- int exception_return = dsc->u.block.load && dsc->u.block.user
- && (regmask & 0x8000) != 0;
- uint32_t status = displaced_read_reg (regs, from, ARM_PS_REGNUM);
- int do_transfer = condition_true (dsc->u.block.cond, status);
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int a = bit (insn, 25), b = bit (insn, 4);
+ uint32_t op1 = bits (insn, 20, 24);
+ int rn_f = bits (insn, 16, 19) == 0xf;
- if (!do_transfer)
- return;
+ if ((!a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02)
+ || (a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02 && !b))
+ return arm_copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 4, 0);
+ else if ((!a && (op1 & 0x17) == 0x02)
+ || (a && (op1 & 0x17) == 0x02 && !b))
+ return arm_copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 4, 1);
+ else if ((!a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03)
+ || (a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03 && !b))
+ return arm_copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 4, 0);
+ else if ((!a && (op1 & 0x17) == 0x03)
+ || (a && (op1 & 0x17) == 0x03 && !b))
+ return arm_copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 4, 1);
+ else if ((!a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06)
+ || (a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06 && !b))
+ return arm_copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 0);
+ else if ((!a && (op1 & 0x17) == 0x06)
+ || (a && (op1 & 0x17) == 0x06 && !b))
+ return arm_copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 1);
+ else if ((!a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07)
+ || (a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07 && !b))
+ return arm_copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 0);
+ else if ((!a && (op1 & 0x17) == 0x07)
+ || (a && (op1 & 0x17) == 0x07 && !b))
+ return arm_copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 1);
- /* If the instruction is ldm rN, {...pc}^, I don't think there's anything
- sensible we can do here. Complain loudly. */
- if (exception_return)
- error (_("Cannot single-step exception return"));
+ /* Should be unreachable. */
+ return 1;
+}
- /* We don't handle any stores here for now. */
- gdb_assert (dsc->u.block.load != 0);
+static int
+arm_decode_media (struct gdbarch *gdbarch, uint32_t insn,
+ struct displaced_step_closure *dsc)
+{
+ switch (bits (insn, 20, 24))
+ {
+ case 0x00: case 0x01: case 0x02: case 0x03:
+ return arm_copy_unmodified (gdbarch, insn, "parallel add/sub signed", dsc);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: emulating block transfer: "
- "%s %s %s\n", dsc->u.block.load ? "ldm" : "stm",
- dsc->u.block.increment ? "inc" : "dec",
- dsc->u.block.before ? "before" : "after");
+ case 0x04: case 0x05: case 0x06: case 0x07:
+ return arm_copy_unmodified (gdbarch, insn, "parallel add/sub unsigned", dsc);
- while (regmask)
- {
- uint32_t memword;
+ case 0x08: case 0x09: case 0x0a: case 0x0b:
+ case 0x0c: case 0x0d: case 0x0e: case 0x0f:
+ return arm_copy_unmodified (gdbarch, insn,
+ "decode/pack/unpack/saturate/reverse", dsc);
- if (inc)
- while (regno <= 15 && (regmask & (1 << regno)) == 0)
- regno++;
+ case 0x18:
+ if (bits (insn, 5, 7) == 0) /* op2. */
+ {
+ if (bits (insn, 12, 15) == 0xf)
+ return arm_copy_unmodified (gdbarch, insn, "usad8", dsc);
+ else
+ return arm_copy_unmodified (gdbarch, insn, "usada8", dsc);
+ }
else
- while (regno >= 0 && (regmask & (1 << regno)) == 0)
- regno--;
-
- xfer_addr += bump_before;
+ return arm_copy_undef (gdbarch, insn, dsc);
- memword = read_memory_unsigned_integer (xfer_addr, 4, byte_order);
- displaced_write_reg (regs, dsc, regno, memword, LOAD_WRITE_PC);
+ case 0x1a: case 0x1b:
+ if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */
+ return arm_copy_unmodified (gdbarch, insn, "sbfx", dsc);
+ else
+ return arm_copy_undef (gdbarch, insn, dsc);
- xfer_addr += bump_after;
+ case 0x1c: case 0x1d:
+ if (bits (insn, 5, 6) == 0x0) /* op2[1:0]. */
+ {
+ if (bits (insn, 0, 3) == 0xf)
+ return arm_copy_unmodified (gdbarch, insn, "bfc", dsc);
+ else
+ return arm_copy_unmodified (gdbarch, insn, "bfi", dsc);
+ }
+ else
+ return arm_copy_undef (gdbarch, insn, dsc);
- regmask &= ~(1 << regno);
+ case 0x1e: case 0x1f:
+ if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */
+ return arm_copy_unmodified (gdbarch, insn, "ubfx", dsc);
+ else
+ return arm_copy_undef (gdbarch, insn, dsc);
}
- if (dsc->u.block.writeback)
- displaced_write_reg (regs, dsc, dsc->u.block.rn, xfer_addr,
- CANNOT_WRITE_PC);
+ /* Should be unreachable. */
+ return 1;
}
-/* Clean up an STM which included the PC in the register list. */
-
-static void
-cleanup_block_store_pc (struct gdbarch *gdbarch, struct regcache *regs,
+static int
+arm_decode_b_bl_ldmstm (struct gdbarch *gdbarch, int32_t insn,
+ struct regcache *regs,
struct displaced_step_closure *dsc)
{
- ULONGEST from = dsc->insn_addr;
- uint32_t status = displaced_read_reg (regs, from, ARM_PS_REGNUM);
- int store_executed = condition_true (dsc->u.block.cond, status);
- CORE_ADDR pc_stored_at, transferred_regs = bitcount (dsc->u.block.regmask);
- CORE_ADDR stm_insn_addr;
- uint32_t pc_val;
- long offset;
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
-
- /* If condition code fails, there's nothing else to do. */
- if (!store_executed)
- return;
+ if (bit (insn, 25))
+ return arm_copy_b_bl_blx (gdbarch, insn, regs, dsc);
+ else
+ return arm_copy_block_xfer (gdbarch, insn, regs, dsc);
+}
- if (dsc->u.block.increment)
- {
- pc_stored_at = dsc->u.block.xfer_addr + 4 * transferred_regs;
+static int
+arm_decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int opcode = bits (insn, 20, 24);
- if (dsc->u.block.before)
- pc_stored_at += 4;
- }
- else
+ switch (opcode)
{
- pc_stored_at = dsc->u.block.xfer_addr;
+ case 0x04: case 0x05: /* VFP/Neon mrrc/mcrr. */
+ return arm_copy_unmodified (gdbarch, insn, "vfp/neon mrrc/mcrr", dsc);
- if (dsc->u.block.before)
- pc_stored_at -= 4;
- }
+ case 0x08: case 0x0a: case 0x0c: case 0x0e:
+ case 0x12: case 0x16:
+ return arm_copy_unmodified (gdbarch, insn, "vfp/neon vstm/vpush", dsc);
- pc_val = read_memory_unsigned_integer (pc_stored_at, 4, byte_order);
- stm_insn_addr = dsc->scratch_base;
- offset = pc_val - stm_insn_addr;
+ case 0x09: case 0x0b: case 0x0d: case 0x0f:
+ case 0x13: case 0x17:
+ return arm_copy_unmodified (gdbarch, insn, "vfp/neon vldm/vpop", dsc);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: detected PC offset %.8lx for "
- "STM instruction\n", offset);
+ case 0x10: case 0x14: case 0x18: case 0x1c: /* vstr. */
+ case 0x11: case 0x15: case 0x19: case 0x1d: /* vldr. */
+ /* Note: no writeback for these instructions. Bit 25 will always be
+ zero though (via caller), so the following works OK. */
+ return arm_copy_copro_load_store (gdbarch, insn, regs, dsc);
+ }
- /* Rewrite the stored PC to the proper value for the non-displaced original
- instruction. */
- write_memory_unsigned_integer (pc_stored_at, 4, byte_order,
- dsc->insn_addr + offset);
+ /* Should be unreachable. */
+ return 1;
}
-/* Clean up an LDM which includes the PC in the register list. We clumped all
- the registers in the transferred list into a contiguous range r0...rX (to
- avoid loading PC directly and losing control of the debugged program), so we
- must undo that here. */
+/* Decode shifted register instructions. */
-static void
-cleanup_block_load_pc (struct gdbarch *gdbarch,
- struct regcache *regs,
- struct displaced_step_closure *dsc)
+static int
+thumb2_decode_dp_shift_reg (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- ULONGEST from = dsc->insn_addr;
- uint32_t status = displaced_read_reg (regs, from, ARM_PS_REGNUM);
- int load_executed = condition_true (dsc->u.block.cond, status), i;
- unsigned int mask = dsc->u.block.regmask, write_reg = 15;
- unsigned int regs_loaded = bitcount (mask);
- unsigned int num_to_shuffle = regs_loaded, clobbered;
-
- /* The method employed here will fail if the register list is fully populated
- (we need to avoid loading PC directly). */
- gdb_assert (num_to_shuffle < 16);
+ /* PC is only allowed to be used in instruction MOV. */
- if (!load_executed)
- return;
+ unsigned int op = bits (insn1, 5, 8);
+ unsigned int rn = bits (insn1, 0, 3);
- clobbered = (1 << num_to_shuffle) - 1;
+ if (op == 0x2 && rn == 0xf) /* MOV */
+ return thumb2_copy_alu_imm (gdbarch, insn1, insn2, regs, dsc);
+ else
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "dp (shift reg)", dsc);
+}
- while (num_to_shuffle > 0)
- {
- if ((mask & (1 << write_reg)) != 0)
- {
- unsigned int read_reg = num_to_shuffle - 1;
- if (read_reg != write_reg)
- {
- ULONGEST rval = displaced_read_reg (regs, from, read_reg);
- displaced_write_reg (regs, dsc, write_reg, rval, LOAD_WRITE_PC);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: move "
- "loaded register r%d to r%d\n"), read_reg,
- write_reg);
- }
- else if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: register "
- "r%d already in the right place\n"),
- write_reg);
+/* Decode extension register load/store. Exactly the same as
+ arm_decode_ext_reg_ld_st. */
- clobbered &= ~(1 << write_reg);
+static int
+thumb2_decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int opcode = bits (insn1, 4, 8);
- num_to_shuffle--;
- }
+ switch (opcode)
+ {
+ case 0x04: case 0x05:
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "vfp/neon vmov", dsc);
+
+ case 0x08: case 0x0c: /* 01x00 */
+ case 0x0a: case 0x0e: /* 01x10 */
+ case 0x12: case 0x16: /* 10x10 */
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "vfp/neon vstm/vpush", dsc);
+
+ case 0x09: case 0x0d: /* 01x01 */
+ case 0x0b: case 0x0f: /* 01x11 */
+ case 0x13: case 0x17: /* 10x11 */
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "vfp/neon vldm/vpop", dsc);
- write_reg--;
+ case 0x10: case 0x14: case 0x18: case 0x1c: /* vstr. */
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "vstr", dsc);
+ case 0x11: case 0x15: case 0x19: case 0x1d: /* vldr. */
+ return thumb2_copy_copro_load_store (gdbarch, insn1, insn2, regs, dsc);
}
- /* Restore any registers we scribbled over. */
- for (write_reg = 0; clobbered != 0; write_reg++)
- {
- if ((clobbered & (1 << write_reg)) != 0)
- {
- displaced_write_reg (regs, dsc, write_reg, dsc->tmp[write_reg],
- CANNOT_WRITE_PC);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: restored "
- "clobbered register r%d\n"), write_reg);
- clobbered &= ~(1 << write_reg);
- }
- }
+ /* Should be unreachable. */
+ return 1;
+}
- /* Perform register writeback manually. */
- if (dsc->u.block.writeback)
- {
- ULONGEST new_rn_val = dsc->u.block.xfer_addr;
+static int
+arm_decode_svc_copro (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int op1 = bits (insn, 20, 25);
+ int op = bit (insn, 4);
+ unsigned int coproc = bits (insn, 8, 11);
+ unsigned int rn = bits (insn, 16, 19);
- if (dsc->u.block.increment)
- new_rn_val += regs_loaded * 4;
+ if ((op1 & 0x20) == 0x00 && (op1 & 0x3a) != 0x00 && (coproc & 0xe) == 0xa)
+ return arm_decode_ext_reg_ld_st (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x21) == 0x00 && (op1 & 0x3a) != 0x00
+ && (coproc & 0xe) != 0xa)
+ /* stc/stc2. */
+ return arm_copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x21) == 0x01 && (op1 & 0x3a) != 0x00
+ && (coproc & 0xe) != 0xa)
+ /* ldc/ldc2 imm/lit. */
+ return arm_copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x3e) == 0x00)
+ return arm_copy_undef (gdbarch, insn, dsc);
+ else if ((op1 & 0x3e) == 0x04 && (coproc & 0xe) == 0xa)
+ return arm_copy_unmodified (gdbarch, insn, "neon 64bit xfer", dsc);
+ else if (op1 == 0x04 && (coproc & 0xe) != 0xa)
+ return arm_copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc);
+ else if (op1 == 0x05 && (coproc & 0xe) != 0xa)
+ return arm_copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc);
+ else if ((op1 & 0x30) == 0x20 && !op)
+ {
+ if ((coproc & 0xe) == 0xa)
+ return arm_copy_unmodified (gdbarch, insn, "vfp dataproc", dsc);
else
- new_rn_val -= regs_loaded * 4;
-
- displaced_write_reg (regs, dsc, dsc->u.block.rn, new_rn_val,
- CANNOT_WRITE_PC);
+ return arm_copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
}
+ else if ((op1 & 0x30) == 0x20 && op)
+ return arm_copy_unmodified (gdbarch, insn, "neon 8/16/32 bit xfer", dsc);
+ else if ((op1 & 0x31) == 0x20 && op && (coproc & 0xe) != 0xa)
+ return arm_copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc);
+ else if ((op1 & 0x31) == 0x21 && op && (coproc & 0xe) != 0xa)
+ return arm_copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc);
+ else if ((op1 & 0x30) == 0x30)
+ return arm_copy_svc (gdbarch, insn, regs, dsc);
+ else
+ return arm_copy_undef (gdbarch, insn, dsc); /* Possibly unreachable. */
}
-/* Handle ldm/stm, apart from some tricky cases which are unlikely to occur
- in user-level code (in particular exception return, ldm rn, {...pc}^). */
-
static int
-copy_block_xfer (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
- struct displaced_step_closure *dsc)
+thumb2_decode_svc_copro (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- int load = bit (insn, 20);
- int user = bit (insn, 22);
- int increment = bit (insn, 23);
- int before = bit (insn, 24);
- int writeback = bit (insn, 21);
- int rn = bits (insn, 16, 19);
- CORE_ADDR from = dsc->insn_addr;
+ unsigned int coproc = bits (insn2, 8, 11);
+ unsigned int op1 = bits (insn1, 4, 9);
+ unsigned int bit_5_8 = bits (insn1, 5, 8);
+ unsigned int bit_9 = bit (insn1, 9);
+ unsigned int bit_4 = bit (insn1, 4);
+ unsigned int rn = bits (insn1, 0, 3);
- /* Block transfers which don't mention PC can be run directly out-of-line. */
- if (rn != 15 && (insn & 0x8000) == 0)
- return copy_unmodified (gdbarch, insn, "ldm/stm", dsc);
-
- if (rn == 15)
+ if (bit_9 == 0)
{
- warning (_("displaced: Unpredictable LDM or STM with base register r15"));
- return copy_unmodified (gdbarch, insn, "unpredictable ldm/stm", dsc);
+ if (bit_5_8 == 2)
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "neon 64bit xfer/mrrc/mrrc2/mcrr/mcrr2",
+ dsc);
+ else if (bit_5_8 == 0) /* UNDEFINED. */
+ return thumb_32bit_copy_undef (gdbarch, insn1, insn2, dsc);
+ else
+ {
+ /*coproc is 101x. SIMD/VFP, ext registers load/store. */
+ if ((coproc & 0xe) == 0xa)
+ return thumb2_decode_ext_reg_ld_st (gdbarch, insn1, insn2, regs,
+ dsc);
+ else /* coproc is not 101x. */
+ {
+ if (bit_4 == 0) /* STC/STC2. */
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "stc/stc2", dsc);
+ else /* LDC/LDC2 {literal, immeidate}. */
+ return thumb2_copy_copro_load_store (gdbarch, insn1, insn2,
+ regs, dsc);
+ }
+ }
}
+ else
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2, "coproc", dsc);
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying block transfer insn "
- "%.8lx\n", (unsigned long) insn);
-
- dsc->u.block.xfer_addr = displaced_read_reg (regs, from, rn);
- dsc->u.block.rn = rn;
-
- dsc->u.block.load = load;
- dsc->u.block.user = user;
- dsc->u.block.increment = increment;
- dsc->u.block.before = before;
- dsc->u.block.writeback = writeback;
- dsc->u.block.cond = bits (insn, 28, 31);
-
- dsc->u.block.regmask = insn & 0xffff;
+ return 0;
+}
- if (load)
- {
- if ((insn & 0xffff) == 0xffff)
- {
- /* LDM with a fully-populated register list. This case is
- particularly tricky. Implement for now by fully emulating the
- instruction (which might not behave perfectly in all cases, but
- these instructions should be rare enough for that not to matter
- too much). */
- dsc->modinsn[0] = ARM_NOP;
+static void
+install_pc_relative (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc, int rd)
+{
+ /* ADR Rd, #imm
- dsc->cleanup = &cleanup_block_load_all;
- }
- else
- {
- /* LDM of a list of registers which includes PC. Implement by
- rewriting the list of registers to be transferred into a
- contiguous chunk r0...rX before doing the transfer, then shuffling
- registers into the correct places in the cleanup routine. */
- unsigned int regmask = insn & 0xffff;
- unsigned int num_in_list = bitcount (regmask), new_regmask, bit = 1;
- unsigned int to = 0, from = 0, i, new_rn;
+ Rewrite as:
- for (i = 0; i < num_in_list; i++)
- dsc->tmp[i] = displaced_read_reg (regs, from, i);
+ Preparation: Rd <- PC
+ Insn: ADD Rd, #imm
+ Cleanup: Null.
+ */
- /* Writeback makes things complicated. We need to avoid clobbering
- the base register with one of the registers in our modified
- register list, but just using a different register can't work in
- all cases, e.g.:
+ /* Rd <- PC */
+ int val = displaced_read_reg (regs, dsc, ARM_PC_REGNUM);
+ displaced_write_reg (regs, dsc, rd, val, CANNOT_WRITE_PC);
+}
- ldm r14!, {r0-r13,pc}
+static int
+thumb_copy_pc_relative_16bit (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc,
+ int rd, unsigned int imm)
+{
- which would need to be rewritten as:
+ /* Encoding T2: ADDS Rd, #imm */
+ dsc->modinsn[0] = (0x3000 | (rd << 8) | imm);
- ldm rN!, {r0-r14}
+ install_pc_relative (gdbarch, regs, dsc, rd);
- but that can't work, because there's no free register for N.
+ return 0;
+}
- Solve this by turning off the writeback bit, and emulating
- writeback manually in the cleanup routine. */
+static int
+thumb_decode_pc_relative_16bit (struct gdbarch *gdbarch, uint16_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rd = bits (insn, 8, 10);
+ unsigned int imm8 = bits (insn, 0, 7);
- if (writeback)
- insn &= ~(1 << 21);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying thumb adr r%d, #%d insn %.4x\n",
+ rd, imm8, insn);
- new_regmask = (1 << num_in_list) - 1;
+ return thumb_copy_pc_relative_16bit (gdbarch, regs, dsc, rd, imm8);
+}
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, _("displaced: LDM r%d%s, "
- "{..., pc}: original reg list %.4x, modified "
- "list %.4x\n"), rn, writeback ? "!" : "",
- (int) insn & 0xffff, new_regmask);
+static int
+thumb_copy_pc_relative_32bit (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rd = bits (insn2, 8, 11);
+ /* Since immediate has the same encoding in ADR ADD and SUB, so we simply
+ extract raw immediate encoding rather than computing immediate. When
+ generating ADD or SUB instruction, we can simply perform OR operation to
+ set immediate into ADD. */
+ unsigned int imm_3_8 = insn2 & 0x70ff;
+ unsigned int imm_i = insn1 & 0x0400; /* Clear all bits except bit 10. */
- dsc->modinsn[0] = (insn & ~0xffff) | (new_regmask & 0xffff);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying thumb adr r%d, #%d:%d insn %.4x%.4x\n",
+ rd, imm_i, imm_3_8, insn1, insn2);
- dsc->cleanup = &cleanup_block_load_pc;
- }
+ if (bit (insn1, 7)) /* Encoding T2 */
+ {
+ /* Encoding T3: SUB Rd, Rd, #imm */
+ dsc->modinsn[0] = (0xf1a0 | rd | imm_i);
+ dsc->modinsn[1] = ((rd << 8) | imm_3_8);
}
- else
+ else /* Encoding T3 */
{
- /* STM of a list of registers which includes PC. Run the instruction
- as-is, but out of line: this will store the wrong value for the PC,
- so we must manually fix up the memory in the cleanup routine.
- Doing things this way has the advantage that we can auto-detect
- the offset of the PC write (which is architecture-dependent) in
- the cleanup routine. */
- dsc->modinsn[0] = insn;
-
- dsc->cleanup = &cleanup_block_store_pc;
+ /* Encoding T3: ADD Rd, Rd, #imm */
+ dsc->modinsn[0] = (0xf100 | rd | imm_i);
+ dsc->modinsn[1] = ((rd << 8) | imm_3_8);
}
+ dsc->numinsns = 2;
+
+ install_pc_relative (gdbarch, regs, dsc, rd);
return 0;
}
-/* Cleanup/copy SVC (SWI) instructions. These two functions are overridden
- for Linux, where some SVC instructions must be treated specially. */
-
-static void
-cleanup_svc (struct gdbarch *gdbarch, struct regcache *regs,
- struct displaced_step_closure *dsc)
+static int
+thumb_copy_16bit_ldr_literal (struct gdbarch *gdbarch, unsigned short insn1,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
+ unsigned int rt = bits (insn1, 8, 10);
+ unsigned int pc;
+ int imm8 = (bits (insn1, 0, 7) << 2);
CORE_ADDR from = dsc->insn_addr;
- CORE_ADDR resume_addr = from + 4;
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: cleanup for svc, resume at "
- "%.8lx\n", (unsigned long) resume_addr);
+ /* LDR Rd, #imm8
- displaced_write_reg (regs, dsc, ARM_PC_REGNUM, resume_addr, BRANCH_WRITE_PC);
-}
+ Rwrite as:
-static int
-copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
- struct regcache *regs, struct displaced_step_closure *dsc)
-{
- CORE_ADDR from = dsc->insn_addr;
+ Preparation: tmp0 <- R0, tmp2 <- R2, tmp3 <- R3, R2 <- PC, R3 <- #imm8;
- /* Allow OS-specific code to override SVC handling. */
- if (dsc->u.svc.copy_svc_os)
- return dsc->u.svc.copy_svc_os (gdbarch, insn, to, regs, dsc);
+ Insn: LDR R0, [R2, R3];
+ Cleanup: R2 <- tmp2, R3 <- tmp3, Rd <- R0, R0 <- tmp0 */
if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying svc insn %.8lx\n",
- (unsigned long) insn);
-
- /* Preparation: none.
- Insn: unmodified svc.
- Cleanup: pc <- insn_addr + 4. */
-
- dsc->modinsn[0] = insn;
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying thumb ldr r%d [pc #%d]\n"
+ , rt, imm8);
- dsc->cleanup = &cleanup_svc;
- /* Pretend we wrote to the PC, so cleanup doesn't set PC to the next
- instruction. */
- dsc->wrote_to_pc = 1;
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[2] = displaced_read_reg (regs, dsc, 2);
+ dsc->tmp[3] = displaced_read_reg (regs, dsc, 3);
+ pc = displaced_read_reg (regs, dsc, ARM_PC_REGNUM);
+ /* The assembler calculates the required value of the offset from the
+ Align(PC,4) value of this instruction to the label. */
+ pc = pc & 0xfffffffc;
- return 0;
-}
+ displaced_write_reg (regs, dsc, 2, pc, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 3, imm8, CANNOT_WRITE_PC);
-/* Copy undefined instructions. */
+ dsc->rd = rt;
+ dsc->u.ldst.xfersize = 4;
+ dsc->u.ldst.rn = 0;
+ dsc->u.ldst.immed = 0;
+ dsc->u.ldst.writeback = 0;
+ dsc->u.ldst.restore_r4 = 0;
-static int
-copy_undef (struct gdbarch *gdbarch, uint32_t insn,
- struct displaced_step_closure *dsc)
-{
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying undefined insn %.8lx\n",
- (unsigned long) insn);
+ dsc->modinsn[0] = 0x58d0; /* ldr r0, [r2, r3]*/
- dsc->modinsn[0] = insn;
+ dsc->cleanup = &cleanup_load;
return 0;
}
-/* Copy unpredictable instructions. */
+/* Copy Thumb cbnz/cbz insruction. */
static int
-copy_unpred (struct gdbarch *gdbarch, uint32_t insn,
- struct displaced_step_closure *dsc)
+thumb_copy_cbnz_cbz (struct gdbarch *gdbarch, uint16_t insn1,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
+ int non_zero = bit (insn1, 11);
+ unsigned int imm5 = (bit (insn1, 9) << 6) | (bits (insn1, 3, 7) << 1);
+ CORE_ADDR from = dsc->insn_addr;
+ int rn = bits (insn1, 0, 2);
+ int rn_val = displaced_read_reg (regs, dsc, rn);
+
+ dsc->u.branch.cond = (rn_val && non_zero) || (!rn_val && !non_zero);
+ /* CBNZ and CBZ do not affect the condition flags. If condition is true,
+ set it INST_AL, so cleanup_branch will know branch is taken, otherwise,
+ condition is false, let it be, cleanup_branch will do nothing. */
+ if (dsc->u.branch.cond)
+ {
+ dsc->u.branch.cond = INST_AL;
+ dsc->u.branch.dest = from + 4 + imm5;
+ }
+ else
+ dsc->u.branch.dest = from + 2;
+
+ dsc->u.branch.link = 0;
+ dsc->u.branch.exchange = 0;
+
if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: copying unpredictable insn "
- "%.8lx\n", (unsigned long) insn);
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s [r%d = 0x%x]"
+ " insn %.4x to %.8lx\n", non_zero ? "cbnz" : "cbz",
+ rn, rn_val, insn1, dsc->u.branch.dest);
- dsc->modinsn[0] = insn;
+ dsc->modinsn[0] = THUMB_NOP;
+ dsc->cleanup = &cleanup_branch;
return 0;
}
-/* The decode_* functions are instruction decoding helpers. They mostly follow
- the presentation in the ARM ARM. */
-
+/* Copy Table Branch Byte/Halfword */
static int
-decode_misc_memhint_neon (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs,
+thumb2_copy_table_branch (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
struct displaced_step_closure *dsc)
{
- unsigned int op1 = bits (insn, 20, 26), op2 = bits (insn, 4, 7);
- unsigned int rn = bits (insn, 16, 19);
+ ULONGEST rn_val, rm_val;
+ int is_tbh = bit (insn2, 4);
+ CORE_ADDR halfwords = 0;
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- if (op1 == 0x10 && (op2 & 0x2) == 0x0 && (rn & 0xe) == 0x0)
- return copy_unmodified (gdbarch, insn, "cps", dsc);
- else if (op1 == 0x10 && op2 == 0x0 && (rn & 0xe) == 0x1)
- return copy_unmodified (gdbarch, insn, "setend", dsc);
- else if ((op1 & 0x60) == 0x20)
- return copy_unmodified (gdbarch, insn, "neon dataproc", dsc);
- else if ((op1 & 0x71) == 0x40)
- return copy_unmodified (gdbarch, insn, "neon elt/struct load/store", dsc);
- else if ((op1 & 0x77) == 0x41)
- return copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc);
- else if ((op1 & 0x77) == 0x45)
- return copy_preload (gdbarch, insn, regs, dsc); /* pli. */
- else if ((op1 & 0x77) == 0x51)
+ rn_val = displaced_read_reg (regs, dsc, bits (insn1, 0, 3));
+ rm_val = displaced_read_reg (regs, dsc, bits (insn2, 0, 3));
+
+ if (is_tbh)
{
- if (rn != 0xf)
- return copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */
- else
- return copy_unpred (gdbarch, insn, dsc);
+ gdb_byte buf[2];
+
+ target_read_memory (rn_val + 2 * rm_val, buf, 2);
+ halfwords = extract_unsigned_integer (buf, 2, byte_order);
}
- else if ((op1 & 0x77) == 0x55)
- return copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */
- else if (op1 == 0x57)
- switch (op2)
- {
- case 0x1: return copy_unmodified (gdbarch, insn, "clrex", dsc);
- case 0x4: return copy_unmodified (gdbarch, insn, "dsb", dsc);
- case 0x5: return copy_unmodified (gdbarch, insn, "dmb", dsc);
- case 0x6: return copy_unmodified (gdbarch, insn, "isb", dsc);
- default: return copy_unpred (gdbarch, insn, dsc);
- }
- else if ((op1 & 0x63) == 0x43)
- return copy_unpred (gdbarch, insn, dsc);
- else if ((op2 & 0x1) == 0x0)
- switch (op1 & ~0x80)
- {
- case 0x61:
- return copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc);
- case 0x65:
- return copy_preload_reg (gdbarch, insn, regs, dsc); /* pli reg. */
- case 0x71: case 0x75:
- /* pld/pldw reg. */
- return copy_preload_reg (gdbarch, insn, regs, dsc);
- case 0x63: case 0x67: case 0x73: case 0x77:
- return copy_unpred (gdbarch, insn, dsc);
- default:
- return copy_undef (gdbarch, insn, dsc);
- }
else
- return copy_undef (gdbarch, insn, dsc); /* Probably unreachable. */
-}
-
-static int
-decode_unconditional (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs, struct displaced_step_closure *dsc)
-{
- if (bit (insn, 27) == 0)
- return decode_misc_memhint_neon (gdbarch, insn, regs, dsc);
- /* Switch on bits: 0bxxxxx321xxx0xxxxxxxxxxxxxxxxxxxx. */
- else switch (((insn & 0x7000000) >> 23) | ((insn & 0x100000) >> 20))
{
- case 0x0: case 0x2:
- return copy_unmodified (gdbarch, insn, "srs", dsc);
+ gdb_byte buf[1];
- case 0x1: case 0x3:
- return copy_unmodified (gdbarch, insn, "rfe", dsc);
-
- case 0x4: case 0x5: case 0x6: case 0x7:
- return copy_b_bl_blx (gdbarch, insn, regs, dsc);
-
- case 0x8:
- switch ((insn & 0xe00000) >> 21)
- {
- case 0x1: case 0x3: case 0x4: case 0x5: case 0x6: case 0x7:
- /* stc/stc2. */
- return copy_copro_load_store (gdbarch, insn, regs, dsc);
-
- case 0x2:
- return copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc);
-
- default:
- return copy_undef (gdbarch, insn, dsc);
- }
-
- case 0x9:
- {
- int rn_f = (bits (insn, 16, 19) == 0xf);
- switch ((insn & 0xe00000) >> 21)
- {
- case 0x1: case 0x3:
- /* ldc/ldc2 imm (undefined for rn == pc). */
- return rn_f ? copy_undef (gdbarch, insn, dsc)
- : copy_copro_load_store (gdbarch, insn, regs, dsc);
+ target_read_memory (rn_val + rm_val, buf, 1);
+ halfwords = extract_unsigned_integer (buf, 1, byte_order);
+ }
- case 0x2:
- return copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: %s base 0x%x offset 0x%x"
+ " offset 0x%x\n", is_tbh ? "tbh" : "tbb",
+ (unsigned int) rn_val, (unsigned int) rm_val,
+ (unsigned int) halfwords);
- case 0x4: case 0x5: case 0x6: case 0x7:
- /* ldc/ldc2 lit (undefined for rn != pc). */
- return rn_f ? copy_copro_load_store (gdbarch, insn, regs, dsc)
- : copy_undef (gdbarch, insn, dsc);
+ dsc->u.branch.cond = INST_AL;
+ dsc->u.branch.link = 0;
+ dsc->u.branch.exchange = 0;
+ dsc->u.branch.dest = dsc->insn_addr + 4 + 2 * halfwords;
- default:
- return copy_undef (gdbarch, insn, dsc);
- }
- }
+ dsc->cleanup = &cleanup_branch;
- case 0xa:
- return copy_unmodified (gdbarch, insn, "stc/stc2", dsc);
+ return 0;
+}
- case 0xb:
- if (bits (insn, 16, 19) == 0xf)
- /* ldc/ldc2 lit. */
- return copy_copro_load_store (gdbarch, insn, regs, dsc);
- else
- return copy_undef (gdbarch, insn, dsc);
+static void
+cleanup_pop_pc_16bit_all (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ /* PC <- r7 */
+ int val = displaced_read_reg (regs, dsc, 7);
+ displaced_write_reg (regs, dsc, ARM_PC_REGNUM, val, BX_WRITE_PC);
- case 0xc:
- if (bit (insn, 4))
- return copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc);
- else
- return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
+ /* r7 <- r8 */
+ val = displaced_read_reg (regs, dsc, 8);
+ displaced_write_reg (regs, dsc, 7, val, CANNOT_WRITE_PC);
- case 0xd:
- if (bit (insn, 4))
- return copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc);
- else
- return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
+ /* r8 <- tmp[0] */
+ displaced_write_reg (regs, dsc, 8, dsc->tmp[0], CANNOT_WRITE_PC);
- default:
- return copy_undef (gdbarch, insn, dsc);
- }
}
-/* Decode miscellaneous instructions in dp/misc encoding space. */
-
static int
-decode_miscellaneous (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs, struct displaced_step_closure *dsc)
+thumb_copy_pop_pc_16bit (struct gdbarch *gdbarch, unsigned short insn1,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned int op2 = bits (insn, 4, 6);
- unsigned int op = bits (insn, 21, 22);
- unsigned int op1 = bits (insn, 16, 19);
-
- switch (op2)
- {
- case 0x0:
- return copy_unmodified (gdbarch, insn, "mrs/msr", dsc);
+ dsc->u.block.regmask = insn1 & 0x00ff;
- case 0x1:
- if (op == 0x1) /* bx. */
- return copy_bx_blx_reg (gdbarch, insn, regs, dsc);
- else if (op == 0x3)
- return copy_unmodified (gdbarch, insn, "clz", dsc);
- else
- return copy_undef (gdbarch, insn, dsc);
+ /* Rewrite instruction: POP {rX, rY, ...,rZ, PC}
+ to :
- case 0x2:
- if (op == 0x1)
- /* Not really supported. */
- return copy_unmodified (gdbarch, insn, "bxj", dsc);
- else
- return copy_undef (gdbarch, insn, dsc);
+ (1) register list is full, that is, r0-r7 are used.
+ Prepare: tmp[0] <- r8
- case 0x3:
- if (op == 0x1)
- return copy_bx_blx_reg (gdbarch, insn, regs, dsc); /* blx register. */
- else
- return copy_undef (gdbarch, insn, dsc);
+ POP {r0, r1, ...., r6, r7}; remove PC from reglist
+ MOV r8, r7; Move value of r7 to r8;
+ POP {r7}; Store PC value into r7.
- case 0x5:
- return copy_unmodified (gdbarch, insn, "saturating add/sub", dsc);
+ Cleanup: PC <- r7, r7 <- r8, r8 <-tmp[0]
- case 0x7:
- if (op == 0x1)
- return copy_unmodified (gdbarch, insn, "bkpt", dsc);
- else if (op == 0x3)
- /* Not really supported. */
- return copy_unmodified (gdbarch, insn, "smc", dsc);
+ (2) register list is not full, supposing there are N registers in
+ register list (except PC, 0 <= N <= 7).
+ Prepare: for each i, 0 - N, tmp[i] <- ri.
- default:
- return copy_undef (gdbarch, insn, dsc);
- }
-}
+ POP {r0, r1, ...., rN};
-static int
-decode_dp_misc (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
- struct displaced_step_closure *dsc)
-{
- if (bit (insn, 25))
- switch (bits (insn, 20, 24))
- {
- case 0x10:
- return copy_unmodified (gdbarch, insn, "movw", dsc);
+ Cleanup: Set registers in original reglist from r0 - rN. Restore r0 - rN
+ from tmp[] properly.
+ */
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying thumb pop {%.8x, pc} insn %.4x\n",
+ dsc->u.block.regmask, insn1);
- case 0x14:
- return copy_unmodified (gdbarch, insn, "movt", dsc);
+ if (dsc->u.block.regmask == 0xff)
+ {
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 8);
- case 0x12: case 0x16:
- return copy_unmodified (gdbarch, insn, "msr imm", dsc);
+ dsc->modinsn[0] = (insn1 & 0xfeff); /* POP {r0,r1,...,r6, r7} */
+ dsc->modinsn[1] = 0x46b8; /* MOV r8, r7 */
+ dsc->modinsn[2] = 0xbc80; /* POP {r7} */
- default:
- return copy_alu_imm (gdbarch, insn, regs, dsc);
- }
+ dsc->numinsns = 3;
+ dsc->cleanup = &cleanup_pop_pc_16bit_all;
+ }
else
{
- uint32_t op1 = bits (insn, 20, 24), op2 = bits (insn, 4, 7);
+ unsigned int num_in_list = bitcount (dsc->u.block.regmask);
+ unsigned int new_regmask, bit = 1;
+ unsigned int to = 0, from = 0, i, new_rn;
- if ((op1 & 0x19) != 0x10 && (op2 & 0x1) == 0x0)
- return copy_alu_reg (gdbarch, insn, regs, dsc);
- else if ((op1 & 0x19) != 0x10 && (op2 & 0x9) == 0x1)
- return copy_alu_shifted_reg (gdbarch, insn, regs, dsc);
- else if ((op1 & 0x19) == 0x10 && (op2 & 0x8) == 0x0)
- return decode_miscellaneous (gdbarch, insn, regs, dsc);
- else if ((op1 & 0x19) == 0x10 && (op2 & 0x9) == 0x8)
- return copy_unmodified (gdbarch, insn, "halfword mul/mla", dsc);
- else if ((op1 & 0x10) == 0x00 && op2 == 0x9)
- return copy_unmodified (gdbarch, insn, "mul/mla", dsc);
- else if ((op1 & 0x10) == 0x10 && op2 == 0x9)
- return copy_unmodified (gdbarch, insn, "synch", dsc);
- else if (op2 == 0xb || (op2 & 0xd) == 0xd)
- /* 2nd arg means "unpriveleged". */
- return copy_extra_ld_st (gdbarch, insn, (op1 & 0x12) == 0x02, regs,
- dsc);
- }
+ for (i = 0; i < num_in_list + 1; i++)
+ dsc->tmp[i] = displaced_read_reg (regs, dsc, i);
- /* Should be unreachable. */
- return 1;
-}
+ new_regmask = (1 << (num_in_list + 1)) - 1;
-static int
-decode_ld_st_word_ubyte (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs,
- struct displaced_step_closure *dsc)
-{
- int a = bit (insn, 25), b = bit (insn, 4);
- uint32_t op1 = bits (insn, 20, 24);
- int rn_f = bits (insn, 16, 19) == 0xf;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: POP "
+ "{..., pc}: original reg list %.4x,"
+ " modified list %.4x\n"),
+ (int) dsc->u.block.regmask, new_regmask);
- if ((!a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02)
- || (a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02 && !b))
- return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 0, 0);
- else if ((!a && (op1 & 0x17) == 0x02)
- || (a && (op1 & 0x17) == 0x02 && !b))
- return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 0, 1);
- else if ((!a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03)
- || (a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03 && !b))
- return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 0, 0);
- else if ((!a && (op1 & 0x17) == 0x03)
- || (a && (op1 & 0x17) == 0x03 && !b))
- return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 0, 1);
- else if ((!a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06)
- || (a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06 && !b))
- return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 0);
- else if ((!a && (op1 & 0x17) == 0x06)
- || (a && (op1 & 0x17) == 0x06 && !b))
- return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 1);
- else if ((!a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07)
- || (a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07 && !b))
- return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 0);
- else if ((!a && (op1 & 0x17) == 0x07)
- || (a && (op1 & 0x17) == 0x07 && !b))
- return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 1);
+ dsc->u.block.regmask |= 0x8000;
+ dsc->u.block.writeback = 0;
+ dsc->u.block.cond = INST_AL;
- /* Should be unreachable. */
- return 1;
-}
+ dsc->modinsn[0] = (insn1 & ~0x1ff) | (new_regmask & 0xff);
-static int
-decode_media (struct gdbarch *gdbarch, uint32_t insn,
- struct displaced_step_closure *dsc)
-{
- switch (bits (insn, 20, 24))
- {
- case 0x00: case 0x01: case 0x02: case 0x03:
- return copy_unmodified (gdbarch, insn, "parallel add/sub signed", dsc);
+ dsc->cleanup = &cleanup_block_load_pc;
+ }
- case 0x04: case 0x05: case 0x06: case 0x07:
- return copy_unmodified (gdbarch, insn, "parallel add/sub unsigned", dsc);
+ return 0;
+}
- case 0x08: case 0x09: case 0x0a: case 0x0b:
- case 0x0c: case 0x0d: case 0x0e: case 0x0f:
- return copy_unmodified (gdbarch, insn,
- "decode/pack/unpack/saturate/reverse", dsc);
+static void
+thumb_process_displaced_16bit_insn (struct gdbarch *gdbarch, uint16_t insn1,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned short op_bit_12_15 = bits (insn1, 12, 15);
+ unsigned short op_bit_10_11 = bits (insn1, 10, 11);
+ int err = 0;
- case 0x18:
- if (bits (insn, 5, 7) == 0) /* op2. */
- {
- if (bits (insn, 12, 15) == 0xf)
- return copy_unmodified (gdbarch, insn, "usad8", dsc);
- else
- return copy_unmodified (gdbarch, insn, "usada8", dsc);
+ /* 16-bit thumb instructions. */
+ switch (op_bit_12_15)
+ {
+ /* Shift (imme), add, subtract, move and compare. */
+ case 0: case 1: case 2: case 3:
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1,
+ "shift/add/sub/mov/cmp",
+ dsc);
+ break;
+ case 4:
+ switch (op_bit_10_11)
+ {
+ case 0: /* Data-processing */
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1,
+ "data-processing",
+ dsc);
+ break;
+ case 1: /* Special data instructions and branch and exchange. */
+ {
+ unsigned short op = bits (insn1, 7, 9);
+ if (op == 6 || op == 7) /* BX or BLX */
+ err = thumb_copy_bx_blx_reg (gdbarch, insn1, regs, dsc);
+ else if (bits (insn1, 6, 7) != 0) /* ADD/MOV/CMP high registers. */
+ err = thumb_copy_alu_reg (gdbarch, insn1, regs, dsc);
+ else
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "special data",
+ dsc);
+ }
+ break;
+ default: /* LDR (literal) */
+ err = thumb_copy_16bit_ldr_literal (gdbarch, insn1, regs, dsc);
}
+ break;
+ case 5: case 6: case 7: case 8: case 9: /* Load/Store single data item */
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "ldr/str", dsc);
+ break;
+ case 10:
+ if (op_bit_10_11 < 2) /* Generate PC-relative address */
+ err = thumb_decode_pc_relative_16bit (gdbarch, insn1, regs, dsc);
+ else /* Generate SP-relative address */
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "sp-relative", dsc);
+ break;
+ case 11: /* Misc 16-bit instructions */
+ {
+ switch (bits (insn1, 8, 11))
+ {
+ case 1: case 3: case 9: case 11: /* CBNZ, CBZ */
+ err = thumb_copy_cbnz_cbz (gdbarch, insn1, regs, dsc);
+ break;
+ case 12: case 13: /* POP */
+ if (bit (insn1, 8)) /* PC is in register list. */
+ err = thumb_copy_pop_pc_16bit (gdbarch, insn1, regs, dsc);
+ else
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "pop", dsc);
+ break;
+ case 15: /* If-Then, and hints */
+ if (bits (insn1, 0, 3))
+ /* If-Then makes up to four following instructions conditional.
+ IT instruction itself is not conditional, so handle it as a
+ common unmodified instruction. */
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "If-Then",
+ dsc);
+ else
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "hints", dsc);
+ break;
+ default:
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "misc", dsc);
+ }
+ }
+ break;
+ case 12:
+ if (op_bit_10_11 < 2) /* Store multiple registers */
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "stm", dsc);
+ else /* Load multiple registers */
+ err = thumb_copy_unmodified_16bit (gdbarch, insn1, "ldm", dsc);
+ break;
+ case 13: /* Conditional branch and supervisor call */
+ if (bits (insn1, 9, 11) != 7) /* conditional branch */
+ err = thumb_copy_b (gdbarch, insn1, dsc);
else
- return copy_undef (gdbarch, insn, dsc);
+ err = thumb_copy_svc (gdbarch, insn1, regs, dsc);
+ break;
+ case 14: /* Unconditional branch */
+ err = thumb_copy_b (gdbarch, insn1, dsc);
+ break;
+ default:
+ err = 1;
+ }
- case 0x1a: case 0x1b:
- if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */
- return copy_unmodified (gdbarch, insn, "sbfx", dsc);
- else
- return copy_undef (gdbarch, insn, dsc);
+ if (err)
+ internal_error (__FILE__, __LINE__,
+ _("thumb_process_displaced_16bit_insn: Instruction decode error"));
+}
+
+static int
+decode_thumb_32bit_ld_mem_hints (struct gdbarch *gdbarch,
+ uint16_t insn1, uint16_t insn2,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ int rt = bits (insn2, 12, 15);
+ int rn = bits (insn1, 0, 3);
+ int op1 = bits (insn1, 7, 8);
+ int err = 0;
- case 0x1c: case 0x1d:
- if (bits (insn, 5, 6) == 0x0) /* op2[1:0]. */
- {
- if (bits (insn, 0, 3) == 0xf)
- return copy_unmodified (gdbarch, insn, "bfc", dsc);
+ switch (bits (insn1, 5, 6))
+ {
+ case 0: /* Load byte and memory hints */
+ if (rt == 0xf) /* PLD/PLI */
+ {
+ if (rn == 0xf)
+ /* PLD literal or Encoding T3 of PLI(immediate, literal). */
+ return thumb2_copy_preload (gdbarch, insn1, insn2, regs, dsc);
else
- return copy_unmodified (gdbarch, insn, "bfi", dsc);
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "pli/pld", dsc);
}
else
- return copy_undef (gdbarch, insn, dsc);
+ {
+ if (rn == 0xf) /* LDRB/LDRSB (literal) */
+ return thumb2_copy_load_literal (gdbarch, insn1, insn2, regs, dsc,
+ 1);
+ else
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "ldrb{reg, immediate}/ldrbt",
+ dsc);
+ }
- case 0x1e: case 0x1f:
- if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */
- return copy_unmodified (gdbarch, insn, "ubfx", dsc);
+ break;
+ case 1: /* Load halfword and memory hints. */
+ if (rt == 0xf) /* PLD{W} and Unalloc memory hint. */
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "pld/unalloc memhint", dsc);
else
- return copy_undef (gdbarch, insn, dsc);
+ {
+ if (rn == 0xf)
+ return thumb2_copy_load_literal (gdbarch, insn1, insn2, regs, dsc,
+ 2);
+ else
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "ldrh/ldrht", dsc);
+ }
+ break;
+ case 2: /* Load word */
+ {
+ int insn2_bit_8_11 = bits (insn2, 8, 11);
+
+ if (rn == 0xf)
+ return thumb2_copy_load_literal (gdbarch, insn1, insn2, regs, dsc, 4);
+ else if (op1 == 0x1) /* Encoding T3 */
+ return thumb2_copy_load_reg_imm (gdbarch, insn1, insn2, regs, dsc,
+ 0, 1);
+ else /* op1 == 0x0 */
+ {
+ if (insn2_bit_8_11 == 0xc || (insn2_bit_8_11 & 0x9) == 0x9)
+ /* LDR (immediate) */
+ return thumb2_copy_load_reg_imm (gdbarch, insn1, insn2, regs,
+ dsc, bit (insn2, 8), 1);
+ else if (insn2_bit_8_11 == 0xe) /* LDRT */
+ return thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "ldrt", dsc);
+ else
+ /* LDR (register) */
+ return thumb2_copy_load_reg_imm (gdbarch, insn1, insn2, regs,
+ dsc, 0, 0);
+ }
+ break;
+ }
+ default:
+ return thumb_32bit_copy_undef (gdbarch, insn1, insn2, dsc);
+ break;
}
-
- /* Should be unreachable. */
- return 1;
-}
-
-static int
-decode_b_bl_ldmstm (struct gdbarch *gdbarch, int32_t insn,
- struct regcache *regs, struct displaced_step_closure *dsc)
-{
- if (bit (insn, 25))
- return copy_b_bl_blx (gdbarch, insn, regs, dsc);
- else
- return copy_block_xfer (gdbarch, insn, regs, dsc);
+ return 0;
}
-static int
-decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint32_t insn,
- struct regcache *regs, struct displaced_step_closure *dsc)
+static void
+thumb_process_displaced_32bit_insn (struct gdbarch *gdbarch, uint16_t insn1,
+ uint16_t insn2, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned int opcode = bits (insn, 20, 24);
+ int err = 0;
+ unsigned short op = bit (insn2, 15);
+ unsigned int op1 = bits (insn1, 11, 12);
- switch (opcode)
+ switch (op1)
{
- case 0x04: case 0x05: /* VFP/Neon mrrc/mcrr. */
- return copy_unmodified (gdbarch, insn, "vfp/neon mrrc/mcrr", dsc);
-
- case 0x08: case 0x0a: case 0x0c: case 0x0e:
- case 0x12: case 0x16:
- return copy_unmodified (gdbarch, insn, "vfp/neon vstm/vpush", dsc);
-
- case 0x09: case 0x0b: case 0x0d: case 0x0f:
- case 0x13: case 0x17:
- return copy_unmodified (gdbarch, insn, "vfp/neon vldm/vpop", dsc);
+ case 1:
+ {
+ switch (bits (insn1, 9, 10))
+ {
+ case 0:
+ if (bit (insn1, 6))
+ {
+ /* Load/store {dual, execlusive}, table branch. */
+ if (bits (insn1, 7, 8) == 1 && bits (insn1, 4, 5) == 1
+ && bits (insn2, 5, 7) == 0)
+ err = thumb2_copy_table_branch (gdbarch, insn1, insn2, regs,
+ dsc);
+ else
+ /* PC is not allowed to use in load/store {dual, exclusive}
+ instructions. */
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "load/store dual/ex", dsc);
+ }
+ else /* load/store multiple */
+ {
+ switch (bits (insn1, 7, 8))
+ {
+ case 0: case 3: /* SRS, RFE */
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "srs/rfe", dsc);
+ break;
+ case 1: case 2: /* LDM/STM/PUSH/POP */
+ err = thumb2_copy_block_xfer (gdbarch, insn1, insn2, regs, dsc);
+ break;
+ }
+ }
+ break;
- case 0x10: case 0x14: case 0x18: case 0x1c: /* vstr. */
- case 0x11: case 0x15: case 0x19: case 0x1d: /* vldr. */
- /* Note: no writeback for these instructions. Bit 25 will always be
- zero though (via caller), so the following works OK. */
- return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ case 1:
+ /* Data-processing (shift register). */
+ err = thumb2_decode_dp_shift_reg (gdbarch, insn1, insn2, regs,
+ dsc);
+ break;
+ default: /* Coprocessor instructions. */
+ err = thumb2_decode_svc_copro (gdbarch, insn1, insn2, regs, dsc);
+ break;
+ }
+ break;
+ }
+ case 2: /* op1 = 2 */
+ if (op) /* Branch and misc control. */
+ {
+ if (bit (insn2, 14) /* BLX/BL */
+ || bit (insn2, 12) /* Unconditional branch */
+ || (bits (insn1, 7, 9) != 0x7)) /* Conditional branch */
+ err = thumb2_copy_b_bl_blx (gdbarch, insn1, insn2, regs, dsc);
+ else
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "misc ctrl", dsc);
+ }
+ else
+ {
+ if (bit (insn1, 9)) /* Data processing (plain binary imm). */
+ {
+ int op = bits (insn1, 4, 8);
+ int rn = bits (insn1, 0, 3);
+ if ((op == 0 || op == 0xa) && rn == 0xf)
+ err = thumb_copy_pc_relative_32bit (gdbarch, insn1, insn2,
+ regs, dsc);
+ else
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "dp/pb", dsc);
+ }
+ else /* Data processing (modified immeidate) */
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "dp/mi", dsc);
+ }
+ break;
+ case 3: /* op1 = 3 */
+ switch (bits (insn1, 9, 10))
+ {
+ case 0:
+ if (bit (insn1, 4))
+ err = decode_thumb_32bit_ld_mem_hints (gdbarch, insn1, insn2,
+ regs, dsc);
+ else /* NEON Load/Store and Store single data item */
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "neon elt/struct load/store",
+ dsc);
+ break;
+ case 1: /* op1 = 3, bits (9, 10) == 1 */
+ switch (bits (insn1, 7, 8))
+ {
+ case 0: case 1: /* Data processing (register) */
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "dp(reg)", dsc);
+ break;
+ case 2: /* Multiply and absolute difference */
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "mul/mua/diff", dsc);
+ break;
+ case 3: /* Long multiply and divide */
+ err = thumb_copy_unmodified_32bit (gdbarch, insn1, insn2,
+ "lmul/lmua", dsc);
+ break;
+ }
+ break;
+ default: /* Coprocessor instructions */
+ err = thumb2_decode_svc_copro (gdbarch, insn1, insn2, regs, dsc);
+ break;
+ }
+ break;
+ default:
+ err = 1;
}
- /* Should be unreachable. */
- return 1;
+ if (err)
+ internal_error (__FILE__, __LINE__,
+ _("thumb_process_displaced_32bit_insn: Instruction decode error"));
+
}
-static int
-decode_svc_copro (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
- struct regcache *regs, struct displaced_step_closure *dsc)
+static void
+thumb_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
+ CORE_ADDR to, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned int op1 = bits (insn, 20, 25);
- int op = bit (insn, 4);
- unsigned int coproc = bits (insn, 8, 11);
- unsigned int rn = bits (insn, 16, 19);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ uint16_t insn1
+ = read_memory_unsigned_integer (from, 2, byte_order_for_code);
- if ((op1 & 0x20) == 0x00 && (op1 & 0x3a) != 0x00 && (coproc & 0xe) == 0xa)
- return decode_ext_reg_ld_st (gdbarch, insn, regs, dsc);
- else if ((op1 & 0x21) == 0x00 && (op1 & 0x3a) != 0x00
- && (coproc & 0xe) != 0xa)
- /* stc/stc2. */
- return copy_copro_load_store (gdbarch, insn, regs, dsc);
- else if ((op1 & 0x21) == 0x01 && (op1 & 0x3a) != 0x00
- && (coproc & 0xe) != 0xa)
- /* ldc/ldc2 imm/lit. */
- return copy_copro_load_store (gdbarch, insn, regs, dsc);
- else if ((op1 & 0x3e) == 0x00)
- return copy_undef (gdbarch, insn, dsc);
- else if ((op1 & 0x3e) == 0x04 && (coproc & 0xe) == 0xa)
- return copy_unmodified (gdbarch, insn, "neon 64bit xfer", dsc);
- else if (op1 == 0x04 && (coproc & 0xe) != 0xa)
- return copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc);
- else if (op1 == 0x05 && (coproc & 0xe) != 0xa)
- return copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc);
- else if ((op1 & 0x30) == 0x20 && !op)
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: process thumb insn %.4x "
+ "at %.8lx\n", insn1, (unsigned long) from);
+
+ dsc->is_thumb = 1;
+ dsc->insn_size = thumb_insn_size (insn1);
+ if (thumb_insn_size (insn1) == 4)
{
- if ((coproc & 0xe) == 0xa)
- return copy_unmodified (gdbarch, insn, "vfp dataproc", dsc);
- else
- return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
+ uint16_t insn2
+ = read_memory_unsigned_integer (from + 2, 2, byte_order_for_code);
+ thumb_process_displaced_32bit_insn (gdbarch, insn1, insn2, regs, dsc);
}
- else if ((op1 & 0x30) == 0x20 && op)
- return copy_unmodified (gdbarch, insn, "neon 8/16/32 bit xfer", dsc);
- else if ((op1 & 0x31) == 0x20 && op && (coproc & 0xe) != 0xa)
- return copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc);
- else if ((op1 & 0x31) == 0x21 && op && (coproc & 0xe) != 0xa)
- return copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc);
- else if ((op1 & 0x30) == 0x30)
- return copy_svc (gdbarch, insn, to, regs, dsc);
else
- return copy_undef (gdbarch, insn, dsc); /* Possibly unreachable. */
+ thumb_process_displaced_16bit_insn (gdbarch, insn1, regs, dsc);
}
void
-arm_process_displaced_insn (struct gdbarch *gdbarch, uint32_t insn,
- CORE_ADDR from, CORE_ADDR to, struct regcache *regs,
+arm_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
+ CORE_ADDR to, struct regcache *regs,
struct displaced_step_closure *dsc)
{
int err = 0;
-
- if (!displaced_in_arm_mode (regs))
- error (_("Displaced stepping is only supported in ARM mode"));
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ uint32_t insn;
/* Most displaced instructions use a 1-instruction scratch space, so set this
here and override below if/when necessary. */
dsc->cleanup = NULL;
dsc->wrote_to_pc = 0;
+ if (!displaced_in_arm_mode (regs))
+ return thumb_process_displaced_insn (gdbarch, from, to, regs, dsc);
+
+ dsc->is_thumb = 0;
+ dsc->insn_size = 4;
+ insn = read_memory_unsigned_integer (from, 4, byte_order_for_code);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: stepping insn %.8lx "
+ "at %.8lx\n", (unsigned long) insn,
+ (unsigned long) from);
+
if ((insn & 0xf0000000) == 0xf0000000)
- err = decode_unconditional (gdbarch, insn, regs, dsc);
+ err = arm_decode_unconditional (gdbarch, insn, regs, dsc);
else switch (((insn & 0x10) >> 4) | ((insn & 0xe000000) >> 24))
{
case 0x0: case 0x1: case 0x2: case 0x3:
- err = decode_dp_misc (gdbarch, insn, regs, dsc);
+ err = arm_decode_dp_misc (gdbarch, insn, regs, dsc);
break;
case 0x4: case 0x5: case 0x6:
- err = decode_ld_st_word_ubyte (gdbarch, insn, regs, dsc);
+ err = arm_decode_ld_st_word_ubyte (gdbarch, insn, regs, dsc);
break;
case 0x7:
- err = decode_media (gdbarch, insn, dsc);
+ err = arm_decode_media (gdbarch, insn, dsc);
break;
case 0x8: case 0x9: case 0xa: case 0xb:
- err = decode_b_bl_ldmstm (gdbarch, insn, regs, dsc);
+ err = arm_decode_b_bl_ldmstm (gdbarch, insn, regs, dsc);
break;
case 0xc: case 0xd: case 0xe: case 0xf:
- err = decode_svc_copro (gdbarch, insn, to, regs, dsc);
+ err = arm_decode_svc_copro (gdbarch, insn, to, regs, dsc);
break;
}
CORE_ADDR to, struct displaced_step_closure *dsc)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- unsigned int i;
+ unsigned int i, len, offset;
enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ int size = dsc->is_thumb? 2 : 4;
+ const unsigned char *bkp_insn;
+ offset = 0;
/* Poke modified instruction(s). */
for (i = 0; i < dsc->numinsns; i++)
{
if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: writing insn %.8lx at "
- "%.8lx\n", (unsigned long) dsc->modinsn[i],
- (unsigned long) to + i * 4);
- write_memory_unsigned_integer (to + i * 4, 4, byte_order_for_code,
+ {
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing insn ");
+ if (size == 4)
+ fprintf_unfiltered (gdb_stdlog, "%.8lx",
+ dsc->modinsn[i]);
+ else if (size == 2)
+ fprintf_unfiltered (gdb_stdlog, "%.4x",
+ (unsigned short)dsc->modinsn[i]);
+
+ fprintf_unfiltered (gdb_stdlog, " at %.8lx\n",
+ (unsigned long) to + offset);
+
+ }
+ write_memory_unsigned_integer (to + offset, size,
+ byte_order_for_code,
dsc->modinsn[i]);
+ offset += size;
+ }
+
+ /* Choose the correct breakpoint instruction. */
+ if (dsc->is_thumb)
+ {
+ bkp_insn = tdep->thumb_breakpoint;
+ len = tdep->thumb_breakpoint_size;
+ }
+ else
+ {
+ bkp_insn = tdep->arm_breakpoint;
+ len = tdep->arm_breakpoint_size;
}
/* Put breakpoint afterwards. */
- write_memory (to + dsc->numinsns * 4, tdep->arm_breakpoint,
- tdep->arm_breakpoint_size);
+ write_memory (to + offset, bkp_insn, len);
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog, "displaced: copy %s->%s: ",
{
struct displaced_step_closure *dsc
= xmalloc (sizeof (struct displaced_step_closure));
- enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
- uint32_t insn = read_memory_unsigned_integer (from, 4, byte_order_for_code);
-
- if (debug_displaced)
- fprintf_unfiltered (gdb_stdlog, "displaced: stepping insn %.8lx "
- "at %.8lx\n", (unsigned long) insn,
- (unsigned long) from);
-
- arm_process_displaced_insn (gdbarch, insn, from, to, regs, dsc);
+ arm_process_displaced_insn (gdbarch, from, to, regs, dsc);
arm_displaced_init_closure (gdbarch, from, to, dsc);
return dsc;
dsc->cleanup (gdbarch, regs, dsc);
if (!dsc->wrote_to_pc)
- regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, dsc->insn_addr + 4);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM,
+ dsc->insn_addr + dsc->insn_size);
+
}
#include "bfd-in2.h"
static int
gdb_print_insn_arm (bfd_vma memaddr, disassemble_info *info)
{
- if (arm_pc_is_thumb (memaddr))
+ struct gdbarch *gdbarch = info->application_data;
+
+ if (arm_pc_is_thumb (gdbarch, memaddr))
{
static asymbol *asym;
static combined_entry_type ce;
1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
C C C C 0 1 1 x x x x x x x x x x x x x x x x x x x x 1 x x x x
- Even this may only true if the condition predicate is true. The
+ Even this may only true if the condition predicate is true. The
following use a condition predicate of ALWAYS so it is always TRUE.
There are other ways of forcing a breakpoint. GNU/Linux, RISC iX,
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
- if (arm_pc_is_thumb (*pcptr))
+ if (arm_pc_is_thumb (gdbarch, *pcptr))
{
*pcptr = UNMAKE_THUMB_ADDR (*pcptr);
{
unsigned short inst1;
inst1 = extract_unsigned_integer (buf, 2, byte_order_for_code);
- if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0)
+ if (thumb_insn_size (inst1) == 4)
{
*lenptr = tdep->thumb2_breakpoint_size;
return tdep->thumb2_breakpoint;
arm_breakpoint_from_pc (gdbarch, pcptr, kindptr);
- if (arm_pc_is_thumb (*pcptr) && *kindptr == 4)
+ if (arm_pc_is_thumb (gdbarch, *pcptr) && *kindptr == 4)
/* The documented magic value for a 32-bit Thumb-2 breakpoint, so
that this is not confused with a 32-bit ARM breakpoint. */
*kindptr = 3;
break;
default:
- internal_error
- (__FILE__, __LINE__,
- _("arm_extract_return_value: Floating point model not supported"));
+ internal_error (__FILE__, __LINE__,
+ _("arm_extract_return_value: "
+ "Floating point model not supported"));
break;
}
}
|| TYPE_CODE (type) == TYPE_CODE_REF
|| TYPE_CODE (type) == TYPE_CODE_ENUM)
{
- /* If the the type is a plain integer, then the access is
- straight-forward. Otherwise we have to play around a bit more. */
+ /* If the type is a plain integer, then the access is
+ straight-forward. Otherwise we have to play around a bit
+ more. */
int len = TYPE_LENGTH (type);
int regno = ARM_A1_REGNUM;
ULONGEST tmp;
for (i = 0; i < TYPE_NFIELDS (type); i++)
{
enum type_code field_type_code;
- field_type_code = TYPE_CODE (check_typedef (TYPE_FIELD_TYPE (type, i)));
+ field_type_code = TYPE_CODE (check_typedef (TYPE_FIELD_TYPE (type,
+ i)));
/* Is it a floating point type field? */
if (field_type_code == TYPE_CODE_FLT)
break;
default:
- internal_error
- (__FILE__, __LINE__,
- _("arm_store_return_value: Floating point model not supported"));
+ internal_error (__FILE__, __LINE__,
+ _("arm_store_return_value: Floating "
+ "point model not supported"));
break;
}
}
gdbarch_info_init (&info);
if (!gdbarch_update_p (info))
- internal_error (__FILE__, __LINE__, "could not update architecture");
+ internal_error (__FILE__, __LINE__, _("could not update architecture"));
}
static void
{
struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
- fprintf_filtered (file, _("\
-The current execution mode assumed (when symbols are unavailable) is \"%s\".\n"),
+ fprintf_filtered (file,
+ _("The current execution mode assumed "
+ "(when symbols are unavailable) is \"%s\".\n"),
arm_fallback_mode_string);
}
{
struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
- fprintf_filtered (file, _("\
-The current execution mode assumed (even when symbols are available) is \"%s\".\n"),
+ fprintf_filtered (file,
+ _("The current execution mode assumed "
+ "(even when symbols are available) is \"%s\".\n"),
arm_force_mode_string);
}
static void
arm_elf_make_msymbol_special(asymbol *sym, struct minimal_symbol *msym)
{
- /* Thumb symbols are of type STT_LOPROC, (synonymous with
- STT_ARM_TFUNC). */
- if (ELF_ST_TYPE (((elf_symbol_type *)sym)->internal_elf_sym.st_info)
- == STT_LOPROC)
+ if (ARM_SYM_BRANCH_TYPE (&((elf_symbol_type *)sym)->internal_elf_sym)
+ == ST_BRANCH_TO_THUMB)
MSYMBOL_SET_SPECIAL (msym);
}
static void
arm_write_pc (struct regcache *regcache, CORE_ADDR pc)
{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
regcache_cooked_write_unsigned (regcache, ARM_PC_REGNUM, pc);
/* If necessary, set the T bit. */
if (arm_apcs_32)
{
- ULONGEST val;
+ ULONGEST val, t_bit;
regcache_cooked_read_unsigned (regcache, ARM_PS_REGNUM, &val);
- if (arm_pc_is_thumb (pc))
- regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM, val | CPSR_T);
+ t_bit = arm_psr_thumb_bit (gdbarch);
+ if (arm_pc_is_thumb (gdbarch, pc))
+ regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM,
+ val | t_bit);
else
regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM,
- val & ~(ULONGEST) CPSR_T);
+ val & ~t_bit);
}
}
ABI, even if a NEON unit is not present. REGNUM is the index of
the quad register, in [0, 15]. */
-static void
+static enum register_status
arm_neon_quad_read (struct gdbarch *gdbarch, struct regcache *regcache,
int regnum, gdb_byte *buf)
{
char name_buf[4];
gdb_byte reg_buf[8];
int offset, double_regnum;
+ enum register_status status;
sprintf (name_buf, "d%d", regnum << 1);
double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
else
offset = 0;
- regcache_raw_read (regcache, double_regnum, reg_buf);
+ status = regcache_raw_read (regcache, double_regnum, reg_buf);
+ if (status != REG_VALID)
+ return status;
memcpy (buf + offset, reg_buf, 8);
offset = 8 - offset;
- regcache_raw_read (regcache, double_regnum + 1, reg_buf);
+ status = regcache_raw_read (regcache, double_regnum + 1, reg_buf);
+ if (status != REG_VALID)
+ return status;
memcpy (buf + offset, reg_buf, 8);
+
+ return REG_VALID;
}
-static void
+static enum register_status
arm_pseudo_read (struct gdbarch *gdbarch, struct regcache *regcache,
int regnum, gdb_byte *buf)
{
if (gdbarch_tdep (gdbarch)->have_neon_pseudos && regnum >= 32 && regnum < 48)
/* Quad-precision register. */
- arm_neon_quad_read (gdbarch, regcache, regnum - 32, buf);
+ return arm_neon_quad_read (gdbarch, regcache, regnum - 32, buf);
else
{
+ enum register_status status;
+
/* Single-precision register. */
gdb_assert (regnum < 32);
double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
strlen (name_buf));
- regcache_raw_read (regcache, double_regnum, reg_buf);
- memcpy (buf, reg_buf + offset, 4);
+ status = regcache_raw_read (regcache, double_regnum, reg_buf);
+ if (status == REG_VALID)
+ memcpy (buf, reg_buf + offset, 4);
+ return status;
}
}
}
}
-static struct value *
-value_of_arm_user_reg (struct frame_info *frame, const void *baton)
-{
- const int *reg_p = baton;
- return value_of_register (*reg_p, frame);
-}
-\f
-static enum gdb_osabi
-arm_elf_osabi_sniffer (bfd *abfd)
-{
- unsigned int elfosabi;
- enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
+static struct value *
+value_of_arm_user_reg (struct frame_info *frame, const void *baton)
+{
+ const int *reg_p = baton;
+ return value_of_register (*reg_p, frame);
+}
+\f
+static enum gdb_osabi
+arm_elf_osabi_sniffer (bfd *abfd)
+{
+ unsigned int elfosabi;
+ enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
+
+ elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
+
+ if (elfosabi == ELFOSABI_ARM)
+ /* GNU tools use this value. Check note sections in this case,
+ as well. */
+ bfd_map_over_sections (abfd,
+ generic_elf_osabi_sniff_abi_tag_sections,
+ &osabi);
+
+ /* Anything else will be handled by the generic ELF sniffer. */
+ return osabi;
+}
+
+static int
+arm_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
+ struct reggroup *group)
+{
+ /* FPS register's type is INT, but belongs to float_reggroup. Beside
+ this, FPS register belongs to save_regroup, restore_reggroup, and
+ all_reggroup, of course. */
+ if (regnum == ARM_FPS_REGNUM)
+ return (group == float_reggroup
+ || group == save_reggroup
+ || group == restore_reggroup
+ || group == all_reggroup);
+ else
+ return default_register_reggroup_p (gdbarch, regnum, group);
+}
+
+\f
+/* Initialize the current architecture based on INFO. If possible,
+ re-use an architecture from ARCHES, which is a list of
+ architectures already created during this debugging session.
+
+ Called e.g. at program startup, when reading a core file, and when
+ reading a binary file. */
+
+static struct gdbarch *
+arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
+{
+ struct gdbarch_tdep *tdep;
+ struct gdbarch *gdbarch;
+ struct gdbarch_list *best_arch;
+ enum arm_abi_kind arm_abi = arm_abi_global;
+ enum arm_float_model fp_model = arm_fp_model;
+ struct tdesc_arch_data *tdesc_data = NULL;
+ int i, is_m = 0;
+ int have_vfp_registers = 0, have_vfp_pseudos = 0, have_neon_pseudos = 0;
+ int have_neon = 0;
+ int have_fpa_registers = 1;
+ const struct target_desc *tdesc = info.target_desc;
+
+ /* If we have an object to base this architecture on, try to determine
+ its ABI. */
+
+ if (arm_abi == ARM_ABI_AUTO && info.abfd != NULL)
+ {
+ int ei_osabi, e_flags;
+
+ switch (bfd_get_flavour (info.abfd))
+ {
+ case bfd_target_aout_flavour:
+ /* Assume it's an old APCS-style ABI. */
+ arm_abi = ARM_ABI_APCS;
+ break;
+
+ case bfd_target_coff_flavour:
+ /* Assume it's an old APCS-style ABI. */
+ /* XXX WinCE? */
+ arm_abi = ARM_ABI_APCS;
+ break;
+
+ case bfd_target_elf_flavour:
+ ei_osabi = elf_elfheader (info.abfd)->e_ident[EI_OSABI];
+ e_flags = elf_elfheader (info.abfd)->e_flags;
+
+ if (ei_osabi == ELFOSABI_ARM)
+ {
+ /* GNU tools used to use this value, but do not for EABI
+ objects. There's nowhere to tag an EABI version
+ anyway, so assume APCS. */
+ arm_abi = ARM_ABI_APCS;
+ }
+ else if (ei_osabi == ELFOSABI_NONE)
+ {
+ int eabi_ver = EF_ARM_EABI_VERSION (e_flags);
+ int attr_arch, attr_profile;
+
+ switch (eabi_ver)
+ {
+ case EF_ARM_EABI_UNKNOWN:
+ /* Assume GNU tools. */
+ arm_abi = ARM_ABI_APCS;
+ break;
+
+ case EF_ARM_EABI_VER4:
+ case EF_ARM_EABI_VER5:
+ arm_abi = ARM_ABI_AAPCS;
+ /* EABI binaries default to VFP float ordering.
+ They may also contain build attributes that can
+ be used to identify if the VFP argument-passing
+ ABI is in use. */
+ if (fp_model == ARM_FLOAT_AUTO)
+ {
+#ifdef HAVE_ELF
+ switch (bfd_elf_get_obj_attr_int (info.abfd,
+ OBJ_ATTR_PROC,
+ Tag_ABI_VFP_args))
+ {
+ case 0:
+ /* "The user intended FP parameter/result
+ passing to conform to AAPCS, base
+ variant". */
+ fp_model = ARM_FLOAT_SOFT_VFP;
+ break;
+ case 1:
+ /* "The user intended FP parameter/result
+ passing to conform to AAPCS, VFP
+ variant". */
+ fp_model = ARM_FLOAT_VFP;
+ break;
+ case 2:
+ /* "The user intended FP parameter/result
+ passing to conform to tool chain-specific
+ conventions" - we don't know any such
+ conventions, so leave it as "auto". */
+ break;
+ default:
+ /* Attribute value not mentioned in the
+ October 2008 ABI, so leave it as
+ "auto". */
+ break;
+ }
+#else
+ fp_model = ARM_FLOAT_SOFT_VFP;
+#endif
+ }
+ break;
+
+ default:
+ /* Leave it as "auto". */
+ warning (_("unknown ARM EABI version 0x%x"), eabi_ver);
+ break;
+ }
- elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
+#ifdef HAVE_ELF
+ /* Detect M-profile programs. This only works if the
+ executable file includes build attributes; GCC does
+ copy them to the executable, but e.g. RealView does
+ not. */
+ attr_arch = bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_PROC,
+ Tag_CPU_arch);
+ attr_profile = bfd_elf_get_obj_attr_int (info.abfd,
+ OBJ_ATTR_PROC,
+ Tag_CPU_arch_profile);
+ /* GCC specifies the profile for v6-M; RealView only
+ specifies the profile for architectures starting with
+ V7 (as opposed to architectures with a tag
+ numerically greater than TAG_CPU_ARCH_V7). */
+ if (!tdesc_has_registers (tdesc)
+ && (attr_arch == TAG_CPU_ARCH_V6_M
+ || attr_arch == TAG_CPU_ARCH_V6S_M
+ || attr_profile == 'M'))
+ tdesc = tdesc_arm_with_m;
+#endif
+ }
- if (elfosabi == ELFOSABI_ARM)
- /* GNU tools use this value. Check note sections in this case,
- as well. */
- bfd_map_over_sections (abfd,
- generic_elf_osabi_sniff_abi_tag_sections,
- &osabi);
+ if (fp_model == ARM_FLOAT_AUTO)
+ {
+ int e_flags = elf_elfheader (info.abfd)->e_flags;
- /* Anything else will be handled by the generic ELF sniffer. */
- return osabi;
-}
+ switch (e_flags & (EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT))
+ {
+ case 0:
+ /* Leave it as "auto". Strictly speaking this case
+ means FPA, but almost nobody uses that now, and
+ many toolchains fail to set the appropriate bits
+ for the floating-point model they use. */
+ break;
+ case EF_ARM_SOFT_FLOAT:
+ fp_model = ARM_FLOAT_SOFT_FPA;
+ break;
+ case EF_ARM_VFP_FLOAT:
+ fp_model = ARM_FLOAT_VFP;
+ break;
+ case EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT:
+ fp_model = ARM_FLOAT_SOFT_VFP;
+ break;
+ }
+ }
-\f
-/* Initialize the current architecture based on INFO. If possible,
- re-use an architecture from ARCHES, which is a list of
- architectures already created during this debugging session.
+ if (e_flags & EF_ARM_BE8)
+ info.byte_order_for_code = BFD_ENDIAN_LITTLE;
- Called e.g. at program startup, when reading a core file, and when
- reading a binary file. */
+ break;
-static struct gdbarch *
-arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
-{
- struct gdbarch_tdep *tdep;
- struct gdbarch *gdbarch;
- struct gdbarch_list *best_arch;
- enum arm_abi_kind arm_abi = arm_abi_global;
- enum arm_float_model fp_model = arm_fp_model;
- struct tdesc_arch_data *tdesc_data = NULL;
- int i;
- int have_vfp_registers = 0, have_vfp_pseudos = 0, have_neon_pseudos = 0;
- int have_neon = 0;
- int have_fpa_registers = 1;
+ default:
+ /* Leave it as "auto". */
+ break;
+ }
+ }
/* Check any target description for validity. */
- if (tdesc_has_registers (info.target_desc))
+ if (tdesc_has_registers (tdesc))
{
/* For most registers we require GDB's default names; but also allow
the numeric names for sp / lr / pc, as a convenience. */
const struct tdesc_feature *feature;
int valid_p;
- feature = tdesc_find_feature (info.target_desc,
+ feature = tdesc_find_feature (tdesc,
"org.gnu.gdb.arm.core");
if (feature == NULL)
- return NULL;
+ {
+ feature = tdesc_find_feature (tdesc,
+ "org.gnu.gdb.arm.m-profile");
+ if (feature == NULL)
+ return NULL;
+ else
+ is_m = 1;
+ }
tdesc_data = tdesc_data_alloc ();
valid_p &= tdesc_numbered_register_choices (feature, tdesc_data,
ARM_PC_REGNUM,
arm_pc_names);
- valid_p &= tdesc_numbered_register (feature, tdesc_data,
- ARM_PS_REGNUM, "cpsr");
+ if (is_m)
+ valid_p &= tdesc_numbered_register (feature, tdesc_data,
+ ARM_PS_REGNUM, "xpsr");
+ else
+ valid_p &= tdesc_numbered_register (feature, tdesc_data,
+ ARM_PS_REGNUM, "cpsr");
if (!valid_p)
{
return NULL;
}
- feature = tdesc_find_feature (info.target_desc,
+ feature = tdesc_find_feature (tdesc,
"org.gnu.gdb.arm.fpa");
if (feature != NULL)
{
else
have_fpa_registers = 0;
- feature = tdesc_find_feature (info.target_desc,
+ feature = tdesc_find_feature (tdesc,
"org.gnu.gdb.xscale.iwmmxt");
if (feature != NULL)
{
/* If we have a VFP unit, check whether the single precision registers
are present. If not, then we will synthesize them as pseudo
registers. */
- feature = tdesc_find_feature (info.target_desc,
+ feature = tdesc_find_feature (tdesc,
"org.gnu.gdb.arm.vfp");
if (feature != NULL)
{
if (!valid_p)
break;
}
+ if (!valid_p && i == 16)
+ valid_p = 1;
- if (!valid_p && i != 16)
+ /* Also require FPSCR. */
+ valid_p &= tdesc_numbered_register (feature, tdesc_data,
+ ARM_FPSCR_REGNUM, "fpscr");
+ if (!valid_p)
{
tdesc_data_cleanup (tdesc_data);
return NULL;
/* If we have VFP, also check for NEON. The architecture allows
NEON without VFP (integer vector operations only), but GDB
does not support that. */
- feature = tdesc_find_feature (info.target_desc,
+ feature = tdesc_find_feature (tdesc,
"org.gnu.gdb.arm.neon");
if (feature != NULL)
{
}
}
- /* If we have an object to base this architecture on, try to determine
- its ABI. */
-
- if (arm_abi == ARM_ABI_AUTO && info.abfd != NULL)
- {
- int ei_osabi, e_flags;
-
- switch (bfd_get_flavour (info.abfd))
- {
- case bfd_target_aout_flavour:
- /* Assume it's an old APCS-style ABI. */
- arm_abi = ARM_ABI_APCS;
- break;
-
- case bfd_target_coff_flavour:
- /* Assume it's an old APCS-style ABI. */
- /* XXX WinCE? */
- arm_abi = ARM_ABI_APCS;
- break;
-
- case bfd_target_elf_flavour:
- ei_osabi = elf_elfheader (info.abfd)->e_ident[EI_OSABI];
- e_flags = elf_elfheader (info.abfd)->e_flags;
-
- if (ei_osabi == ELFOSABI_ARM)
- {
- /* GNU tools used to use this value, but do not for EABI
- objects. There's nowhere to tag an EABI version
- anyway, so assume APCS. */
- arm_abi = ARM_ABI_APCS;
- }
- else if (ei_osabi == ELFOSABI_NONE)
- {
- int eabi_ver = EF_ARM_EABI_VERSION (e_flags);
-
- switch (eabi_ver)
- {
- case EF_ARM_EABI_UNKNOWN:
- /* Assume GNU tools. */
- arm_abi = ARM_ABI_APCS;
- break;
-
- case EF_ARM_EABI_VER4:
- case EF_ARM_EABI_VER5:
- arm_abi = ARM_ABI_AAPCS;
- /* EABI binaries default to VFP float ordering.
- They may also contain build attributes that can
- be used to identify if the VFP argument-passing
- ABI is in use. */
- if (fp_model == ARM_FLOAT_AUTO)
- {
-#ifdef HAVE_ELF
- switch (bfd_elf_get_obj_attr_int (info.abfd,
- OBJ_ATTR_PROC,
- Tag_ABI_VFP_args))
- {
- case 0:
- /* "The user intended FP parameter/result
- passing to conform to AAPCS, base
- variant". */
- fp_model = ARM_FLOAT_SOFT_VFP;
- break;
- case 1:
- /* "The user intended FP parameter/result
- passing to conform to AAPCS, VFP
- variant". */
- fp_model = ARM_FLOAT_VFP;
- break;
- case 2:
- /* "The user intended FP parameter/result
- passing to conform to tool chain-specific
- conventions" - we don't know any such
- conventions, so leave it as "auto". */
- break;
- default:
- /* Attribute value not mentioned in the
- October 2008 ABI, so leave it as
- "auto". */
- break;
- }
-#else
- fp_model = ARM_FLOAT_SOFT_VFP;
-#endif
- }
- break;
-
- default:
- /* Leave it as "auto". */
- warning (_("unknown ARM EABI version 0x%x"), eabi_ver);
- break;
- }
- }
-
- if (fp_model == ARM_FLOAT_AUTO)
- {
- int e_flags = elf_elfheader (info.abfd)->e_flags;
-
- switch (e_flags & (EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT))
- {
- case 0:
- /* Leave it as "auto". Strictly speaking this case
- means FPA, but almost nobody uses that now, and
- many toolchains fail to set the appropriate bits
- for the floating-point model they use. */
- break;
- case EF_ARM_SOFT_FLOAT:
- fp_model = ARM_FLOAT_SOFT_FPA;
- break;
- case EF_ARM_VFP_FLOAT:
- fp_model = ARM_FLOAT_VFP;
- break;
- case EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT:
- fp_model = ARM_FLOAT_SOFT_VFP;
- break;
- }
- }
-
- if (e_flags & EF_ARM_BE8)
- info.byte_order_for_code = BFD_ENDIAN_LITTLE;
-
- break;
-
- default:
- /* Leave it as "auto". */
- break;
- }
- }
-
/* If there is already a candidate, use it. */
for (best_arch = gdbarch_list_lookup_by_info (arches, &info);
best_arch != NULL;
since gdbarches with a different target description are
automatically disqualified. */
+ /* Do check is_m, though, since it might come from the binary. */
+ if (is_m != gdbarch_tdep (best_arch->gdbarch)->is_m)
+ continue;
+
/* Found a match. */
break;
}
These are gdbarch discriminators, like the OSABI. */
tdep->arm_abi = arm_abi;
tdep->fp_model = fp_model;
+ tdep->is_m = is_m;
tdep->have_fpa_registers = have_fpa_registers;
tdep->have_vfp_registers = have_vfp_registers;
tdep->have_vfp_pseudos = have_vfp_pseudos;
/* Advance PC across function entry code. */
set_gdbarch_skip_prologue (gdbarch, arm_skip_prologue);
+ /* Detect whether PC is in function epilogue. */
+ set_gdbarch_in_function_epilogue_p (gdbarch, arm_in_function_epilogue_p);
+
/* Skip trampolines. */
set_gdbarch_skip_trampoline_code (gdbarch, arm_skip_stub);
arm_remote_breakpoint_from_pc);
/* Information about registers, etc. */
- set_gdbarch_deprecated_fp_regnum (gdbarch, ARM_FP_REGNUM); /* ??? */
set_gdbarch_sp_regnum (gdbarch, ARM_SP_REGNUM);
set_gdbarch_pc_regnum (gdbarch, ARM_PC_REGNUM);
set_gdbarch_num_regs (gdbarch, ARM_NUM_REGS);
set_gdbarch_register_type (gdbarch, arm_register_type);
+ set_gdbarch_register_reggroup_p (gdbarch, arm_register_reggroup_p);
/* This "info float" is FPA-specific. Use the generic version if we
do not have FPA. */
/* Add some default predicates. */
frame_unwind_append_unwinder (gdbarch, &arm_stub_unwind);
dwarf2_append_unwinders (gdbarch);
+ frame_unwind_append_unwinder (gdbarch, &arm_exidx_unwind);
frame_unwind_append_unwinder (gdbarch, &arm_prologue_unwind);
/* Now we have tuned the configuration, set a few final things,
if (tdep->arm_abi == ARM_ABI_AUTO)
tdep->arm_abi = ARM_ABI_APCS;
+ /* Watchpoints are not steppable. */
+ set_gdbarch_have_nonsteppable_watchpoint (gdbarch, 1);
+
/* We used to default to FPA for generic ARM, but almost nobody
uses that now, and we now provide a way for the user to force
the model. So default to the most useful variant. */
{
set_tdesc_pseudo_register_name (gdbarch, arm_register_name);
- tdesc_use_registers (gdbarch, info.target_desc, tdesc_data);
+ tdesc_use_registers (gdbarch, tdesc, tdesc_data);
/* Override tdesc_register_type to adjust the types of VFP
registers for NEON. */
arm_objfile_data_key
= register_objfile_data_with_cleanup (NULL, arm_objfile_data_free);
+ /* Add ourselves to objfile event chain. */
+ observer_attach_new_objfile (arm_exidx_new_objfile);
+ arm_exidx_data_key
+ = register_objfile_data_with_cleanup (NULL, arm_exidx_data_free);
+
/* Register an ELF OS ABI sniffer for ARM binaries. */
gdbarch_register_osabi_sniffer (bfd_arch_arm,
bfd_target_elf_flavour,
arm_elf_osabi_sniffer);
+ /* Initialize the standard target descriptions. */
+ initialize_tdesc_arm_with_m ();
+ initialize_tdesc_arm_with_iwmmxt ();
+ initialize_tdesc_arm_with_vfpv2 ();
+ initialize_tdesc_arm_with_vfpv3 ();
+ initialize_tdesc_arm_with_neon ();
+
/* Get the number of possible sets of register names defined in opcodes. */
num_disassembly_options = get_arm_regname_num_options ();
_("Show the disassembly style."),
helptext,
set_disassembly_style_sfunc,
- NULL, /* FIXME: i18n: The disassembly style is \"%s\". */
+ NULL, /* FIXME: i18n: The disassembly style is
+ \"%s\". */
&setarmcmdlist, &showarmcmdlist);
add_setshow_boolean_cmd ("apcs32", no_class, &arm_apcs_32,
_("Show usage of ARM 32-bit mode."),
_("When off, a 26-bit PC will be used."),
NULL,
- NULL, /* FIXME: i18n: Usage of ARM 32-bit mode is %s. */
+ NULL, /* FIXME: i18n: Usage of ARM 32-bit
+ mode is %s. */
&setarmcmdlist, &showarmcmdlist);
/* Add a command to allow the user to force the FPU model. */
projects / deliverable / binutils-gdb.git / blobdiff