/* Frame unwinder for frames with DWARF Call Frame Information.
- Copyright 2003 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2007, 2008 Free Software Foundation, Inc.
Contributed by Mark Kettenis.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "dwarf2expr.h"
#include "symtab.h"
#include "objfiles.h"
#include "regcache.h"
+#include "value.h"
#include "gdb_assert.h"
#include "gdb_string.h"
#include "complaints.h"
#include "dwarf2-frame.h"
+struct comp_unit;
+
/* Call Frame Information (CFI). */
/* Common Information Entry (CIE). */
struct dwarf2_cie
{
+ /* Computation Unit for this CIE. */
+ struct comp_unit *unit;
+
/* Offset into the .debug_frame section where this CIE was found.
Used to identify this CIE. */
ULONGEST cie_pointer;
ULONGEST return_address_register;
/* Instruction sequence to initialize a register set. */
- unsigned char *initial_instructions;
- unsigned char *end;
+ gdb_byte *initial_instructions;
+ gdb_byte *end;
+
+ /* Saved augmentation, in case it's needed later. */
+ char *augmentation;
/* Encoding of addresses. */
- unsigned char encoding;
+ gdb_byte encoding;
+
+ /* Target address size in bytes. */
+ int addr_size;
/* True if a 'z' augmentation existed. */
unsigned char saw_z_augmentation;
+ /* True if an 'S' augmentation existed. */
+ unsigned char signal_frame;
+
+ /* The version recorded in the CIE. */
+ unsigned char version;
+
struct dwarf2_cie *next;
};
CORE_ADDR address_range;
/* Instruction sequence. */
- unsigned char *instructions;
- unsigned char *end;
+ gdb_byte *instructions;
+ gdb_byte *end;
+
+ /* True if this FDE is read from a .eh_frame instead of a .debug_frame
+ section. */
+ unsigned char eh_frame_p;
struct dwarf2_fde *next;
};
+/* A minimal decoding of DWARF2 compilation units. We only decode
+ what's needed to get to the call frame information. */
+
+struct comp_unit
+{
+ /* Keep the bfd convenient. */
+ bfd *abfd;
+
+ struct objfile *objfile;
+
+ /* Linked list of CIEs for this object. */
+ struct dwarf2_cie *cie;
+
+ /* Pointer to the .debug_frame section loaded into memory. */
+ gdb_byte *dwarf_frame_buffer;
+
+ /* Length of the loaded .debug_frame section. */
+ unsigned long dwarf_frame_size;
+
+ /* Pointer to the .debug_frame section. */
+ asection *dwarf_frame_section;
+
+ /* Base for DW_EH_PE_datarel encodings. */
+ bfd_vma dbase;
+
+ /* Base for DW_EH_PE_textrel encodings. */
+ bfd_vma tbase;
+};
+
static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc);
+
+static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum,
+ int eh_frame_p);
+
+static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding,
+ int ptr_len, gdb_byte *buf,
+ unsigned int *bytes_read_ptr,
+ CORE_ADDR func_base);
\f
/* Structure describing a frame state. */
another register, or a location expression. */
struct dwarf2_frame_state_reg_info
{
- struct dwarf2_frame_state_reg
- {
- union {
- LONGEST offset;
- ULONGEST reg;
- unsigned char *exp;
- } loc;
- ULONGEST exp_len;
- enum {
- REG_UNSAVED,
- REG_SAVED_OFFSET,
- REG_SAVED_REG,
- REG_SAVED_EXP,
- REG_UNMODIFIED
- } how;
- } *reg;
+ struct dwarf2_frame_state_reg *reg;
int num_regs;
/* Used to implement DW_CFA_remember_state. */
LONGEST cfa_offset;
ULONGEST cfa_reg;
- unsigned char *cfa_exp;
+ gdb_byte *cfa_exp;
enum {
CFA_UNSET,
CFA_REG_OFFSET,
LONGEST data_align;
ULONGEST code_align;
ULONGEST retaddr_column;
+
+ /* Flags for known producer quirks. */
+
+ /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa
+ and DW_CFA_def_cfa_offset takes a factored offset. */
+ int armcc_cfa_offsets_sf;
+
+ /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that
+ the CFA is defined as REG - OFFSET rather than REG + OFFSET. */
+ int armcc_cfa_offsets_reversed;
};
/* Store the length the expression for the CFA in the `cfa_reg' field,
which is unused in that case. */
#define cfa_exp_len cfa_reg
-/* Assert that the register set RS is large enough to store NUM_REGS
+/* Assert that the register set RS is large enough to store gdbarch_num_regs
columns. If necessary, enlarge the register set. */
static void
static struct dwarf2_frame_state_reg *
dwarf2_frame_state_copy_regs (struct dwarf2_frame_state_reg_info *rs)
{
- size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg_info);
+ size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg);
struct dwarf2_frame_state_reg *reg;
reg = (struct dwarf2_frame_state_reg *) xmalloc (size);
static CORE_ADDR
read_reg (void *baton, int reg)
{
- struct frame_info *next_frame = (struct frame_info *) baton;
+ struct frame_info *this_frame = (struct frame_info *) baton;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
int regnum;
- char *buf;
+ gdb_byte *buf;
- regnum = DWARF2_REG_TO_REGNUM (reg);
+ regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg);
- buf = (char *) alloca (register_size (current_gdbarch, regnum));
- frame_unwind_register (next_frame, regnum, buf);
- return extract_typed_address (buf, builtin_type_void_data_ptr);
+ buf = alloca (register_size (gdbarch, regnum));
+ get_frame_register (this_frame, regnum, buf);
+
+ /* Convert the register to an integer. This returns a LONGEST
+ rather than a CORE_ADDR, but unpack_pointer does the same thing
+ under the covers, and this makes more sense for non-pointer
+ registers. Maybe read_reg and the associated interfaces should
+ deal with "struct value" instead of CORE_ADDR. */
+ return unpack_long (register_type (gdbarch, regnum), buf);
}
static void
-read_mem (void *baton, char *buf, CORE_ADDR addr, size_t len)
+read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len)
{
read_memory (addr, buf, len);
}
static void
-no_get_frame_base (void *baton, unsigned char **start, size_t *length)
+no_get_frame_base (void *baton, gdb_byte **start, size_t *length)
{
internal_error (__FILE__, __LINE__,
- "Support for DW_OP_fbreg is unimplemented");
+ _("Support for DW_OP_fbreg is unimplemented"));
}
static CORE_ADDR
no_get_tls_address (void *baton, CORE_ADDR offset)
{
internal_error (__FILE__, __LINE__,
- "Support for DW_OP_GNU_push_tls_address is unimplemented");
+ _("Support for DW_OP_GNU_push_tls_address is unimplemented"));
+}
+
+/* Execute the required actions for both the DW_CFA_restore and
+DW_CFA_restore_extended instructions. */
+static void
+dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num,
+ struct dwarf2_frame_state *fs, int eh_frame_p)
+{
+ ULONGEST reg;
+
+ gdb_assert (fs->initial.reg);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p);
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+
+ /* Check if this register was explicitly initialized in the
+ CIE initial instructions. If not, default the rule to
+ UNSPECIFIED. */
+ if (reg < fs->initial.num_regs)
+ fs->regs.reg[reg] = fs->initial.reg[reg];
+ else
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED;
+
+ if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED)
+ complaint (&symfile_complaints, _("\
+incomplete CFI data; DW_CFA_restore unspecified\n\
+register %s (#%d) at 0x%s"),
+ gdbarch_register_name
+ (gdbarch, gdbarch_dwarf2_reg_to_regnum (gdbarch, reg)),
+ gdbarch_dwarf2_reg_to_regnum (gdbarch, reg),
+ paddr (fs->pc));
}
static CORE_ADDR
-execute_stack_op (unsigned char *exp, ULONGEST len,
- struct frame_info *next_frame, CORE_ADDR initial)
+execute_stack_op (gdb_byte *exp, ULONGEST len, int addr_size,
+ struct frame_info *this_frame, CORE_ADDR initial)
{
struct dwarf_expr_context *ctx;
CORE_ADDR result;
ctx = new_dwarf_expr_context ();
- ctx->baton = next_frame;
+ ctx->gdbarch = get_frame_arch (this_frame);
+ ctx->addr_size = addr_size;
+ ctx->baton = this_frame;
ctx->read_reg = read_reg;
ctx->read_mem = read_mem;
ctx->get_frame_base = no_get_frame_base;
result = dwarf_expr_fetch (ctx, 0);
if (ctx->in_reg)
- result = read_reg (next_frame, result);
+ result = read_reg (this_frame, result);
free_dwarf_expr_context (ctx);
\f
static void
-execute_cfa_program (unsigned char *insn_ptr, unsigned char *insn_end,
- struct frame_info *next_frame,
+execute_cfa_program (struct dwarf2_fde *fde, gdb_byte *insn_ptr,
+ gdb_byte *insn_end, struct frame_info *this_frame,
struct dwarf2_frame_state *fs)
{
- CORE_ADDR pc = frame_pc_unwind (next_frame);
+ int eh_frame_p = fde->eh_frame_p;
+ CORE_ADDR pc = get_frame_pc (this_frame);
int bytes_read;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
while (insn_ptr < insn_end && fs->pc <= pc)
{
- unsigned char insn = *insn_ptr++;
+ gdb_byte insn = *insn_ptr++;
ULONGEST utmp, reg;
LONGEST offset;
else if ((insn & 0xc0) == DW_CFA_offset)
{
reg = insn & 0x3f;
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
offset = utmp * fs->data_align;
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
- fs->regs.reg[reg].how = REG_SAVED_OFFSET;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
fs->regs.reg[reg].loc.offset = offset;
}
else if ((insn & 0xc0) == DW_CFA_restore)
{
- gdb_assert (fs->initial.reg);
reg = insn & 0x3f;
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
- fs->regs.reg[reg] = fs->initial.reg[reg];
+ dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p);
}
else
{
switch (insn)
{
case DW_CFA_set_loc:
- fs->pc = dwarf2_read_address (insn_ptr, insn_end, &bytes_read);
+ fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding,
+ fde->cie->addr_size, insn_ptr,
+ &bytes_read, fde->initial_location);
+ /* Apply the objfile offset for relocatable objects. */
+ fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets,
+ SECT_OFF_TEXT (fde->cie->unit->objfile));
insn_ptr += bytes_read;
break;
case DW_CFA_offset_extended:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
offset = utmp * fs->data_align;
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
- fs->regs.reg[reg].how = REG_SAVED_OFFSET;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
fs->regs.reg[reg].loc.offset = offset;
break;
case DW_CFA_restore_extended:
- gdb_assert (fs->initial.reg);
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
- fs->regs.reg[reg] = fs->initial.reg[reg];
+ dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p);
break;
case DW_CFA_undefined:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
- fs->regs.reg[reg].how = REG_UNSAVED;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED;
break;
case DW_CFA_same_value:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
- fs->regs.reg[reg].how = REG_UNMODIFIED;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE;
break;
case DW_CFA_register:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p);
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG;
fs->regs.reg[reg].loc.reg = utmp;
break;
{
struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev;
- gdb_assert (old_rs);
-
- xfree (fs->regs.reg);
- fs->regs = *old_rs;
- xfree (old_rs);
+ if (old_rs == NULL)
+ {
+ complaint (&symfile_complaints, _("\
+bad CFI data; mismatched DW_CFA_restore_state at 0x%s"), paddr (fs->pc));
+ }
+ else
+ {
+ xfree (fs->regs.reg);
+ fs->regs = *old_rs;
+ xfree (old_rs);
+ }
}
break;
case DW_CFA_def_cfa:
insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+
+ if (fs->armcc_cfa_offsets_sf)
+ utmp *= fs->data_align;
+
fs->cfa_offset = utmp;
fs->cfa_how = CFA_REG_OFFSET;
break;
case DW_CFA_def_cfa_register:
insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg);
+ fs->cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, fs->cfa_reg,
+ eh_frame_p);
fs->cfa_how = CFA_REG_OFFSET;
break;
case DW_CFA_def_cfa_offset:
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_offset);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+
+ if (fs->armcc_cfa_offsets_sf)
+ utmp *= fs->data_align;
+
+ fs->cfa_offset = utmp;
/* cfa_how deliberately not set. */
break;
+ case DW_CFA_nop:
+ break;
+
case DW_CFA_def_cfa_expression:
insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_exp_len);
fs->cfa_exp = insn_ptr;
case DW_CFA_expression:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
fs->regs.reg[reg].loc.exp = insn_ptr;
fs->regs.reg[reg].exp_len = utmp;
- fs->regs.reg[reg].how = REG_SAVED_EXP;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP;
insn_ptr += utmp;
break;
- case DW_CFA_nop:
+ case DW_CFA_offset_extended_sf:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
+ offset *= fs->data_align;
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
+ fs->regs.reg[reg].loc.offset = offset;
+ break;
+
+ case DW_CFA_val_offset:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ offset = utmp * fs->data_align;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET;
+ fs->regs.reg[reg].loc.offset = offset;
+ break;
+
+ case DW_CFA_val_offset_sf:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
+ offset *= fs->data_align;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET;
+ fs->regs.reg[reg].loc.offset = offset;
+ break;
+
+ case DW_CFA_val_expression:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ fs->regs.reg[reg].loc.exp = insn_ptr;
+ fs->regs.reg[reg].exp_len = utmp;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP;
+ insn_ptr += utmp;
+ break;
+
+ case DW_CFA_def_cfa_sf:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg);
+ fs->cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, fs->cfa_reg,
+ eh_frame_p);
+ insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
+ fs->cfa_offset = offset * fs->data_align;
+ fs->cfa_how = CFA_REG_OFFSET;
+ break;
+
+ case DW_CFA_def_cfa_offset_sf:
+ insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
+ fs->cfa_offset = offset * fs->data_align;
+ /* cfa_how deliberately not set. */
+ break;
+
+ case DW_CFA_GNU_window_save:
+ /* This is SPARC-specific code, and contains hard-coded
+ constants for the register numbering scheme used by
+ GCC. Rather than having a architecture-specific
+ operation that's only ever used by a single
+ architecture, we provide the implementation here.
+ Incidentally that's what GCC does too in its
+ unwinder. */
+ {
+ int size = register_size (gdbarch, 0);
+ dwarf2_frame_state_alloc_regs (&fs->regs, 32);
+ for (reg = 8; reg < 16; reg++)
+ {
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG;
+ fs->regs.reg[reg].loc.reg = reg + 16;
+ }
+ for (reg = 16; reg < 32; reg++)
+ {
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
+ fs->regs.reg[reg].loc.offset = (reg - 16) * size;
+ }
+ }
break;
case DW_CFA_GNU_args_size:
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
break;
+ case DW_CFA_GNU_negative_offset_extended:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &offset);
+ offset *= fs->data_align;
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
+ fs->regs.reg[reg].loc.offset = -offset;
+ break;
+
default:
- internal_error (__FILE__, __LINE__, "Unknown CFI encountered.");
+ internal_error (__FILE__, __LINE__, _("Unknown CFI encountered."));
}
}
}
dwarf2_frame_state_free_regs (fs->regs.prev);
fs->regs.prev = NULL;
}
+\f
+
+/* Architecture-specific operations. */
+
+/* Per-architecture data key. */
+static struct gdbarch_data *dwarf2_frame_data;
+
+struct dwarf2_frame_ops
+{
+ /* Pre-initialize the register state REG for register REGNUM. */
+ void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *,
+ struct frame_info *);
+
+ /* Check whether the THIS_FRAME is a signal trampoline. */
+ int (*signal_frame_p) (struct gdbarch *, struct frame_info *);
+
+ /* Convert .eh_frame register number to DWARF register number, or
+ adjust .debug_frame register number. */
+ int (*adjust_regnum) (struct gdbarch *, int, int);
+};
+
+/* Default architecture-specific register state initialization
+ function. */
+
+static void
+dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum,
+ struct dwarf2_frame_state_reg *reg,
+ struct frame_info *this_frame)
+{
+ /* If we have a register that acts as a program counter, mark it as
+ a destination for the return address. If we have a register that
+ serves as the stack pointer, arrange for it to be filled with the
+ call frame address (CFA). The other registers are marked as
+ unspecified.
+
+ We copy the return address to the program counter, since many
+ parts in GDB assume that it is possible to get the return address
+ by unwinding the program counter register. However, on ISA's
+ with a dedicated return address register, the CFI usually only
+ contains information to unwind that return address register.
+
+ The reason we're treating the stack pointer special here is
+ because in many cases GCC doesn't emit CFI for the stack pointer
+ and implicitly assumes that it is equal to the CFA. This makes
+ some sense since the DWARF specification (version 3, draft 8,
+ p. 102) says that:
+
+ "Typically, the CFA is defined to be the value of the stack
+ pointer at the call site in the previous frame (which may be
+ different from its value on entry to the current frame)."
+
+ However, this isn't true for all platforms supported by GCC
+ (e.g. IBM S/390 and zSeries). Those architectures should provide
+ their own architecture-specific initialization function. */
+
+ if (regnum == gdbarch_pc_regnum (gdbarch))
+ reg->how = DWARF2_FRAME_REG_RA;
+ else if (regnum == gdbarch_sp_regnum (gdbarch))
+ reg->how = DWARF2_FRAME_REG_CFA;
+}
+
+/* Return a default for the architecture-specific operations. */
+
+static void *
+dwarf2_frame_init (struct obstack *obstack)
+{
+ struct dwarf2_frame_ops *ops;
+
+ ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops);
+ ops->init_reg = dwarf2_frame_default_init_reg;
+ return ops;
+}
+
+/* Set the architecture-specific register state initialization
+ function for GDBARCH to INIT_REG. */
+
+void
+dwarf2_frame_set_init_reg (struct gdbarch *gdbarch,
+ void (*init_reg) (struct gdbarch *, int,
+ struct dwarf2_frame_state_reg *,
+ struct frame_info *))
+{
+ struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ ops->init_reg = init_reg;
+}
+
+/* Pre-initialize the register state REG for register REGNUM. */
+
+static void
+dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
+ struct dwarf2_frame_state_reg *reg,
+ struct frame_info *this_frame)
+{
+ struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ ops->init_reg (gdbarch, regnum, reg, this_frame);
+}
+
+/* Set the architecture-specific signal trampoline recognition
+ function for GDBARCH to SIGNAL_FRAME_P. */
+
+void
+dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch,
+ int (*signal_frame_p) (struct gdbarch *,
+ struct frame_info *))
+{
+ struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ ops->signal_frame_p = signal_frame_p;
+}
+
+/* Query the architecture-specific signal frame recognizer for
+ THIS_FRAME. */
+
+static int
+dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch,
+ struct frame_info *this_frame)
+{
+ struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ if (ops->signal_frame_p == NULL)
+ return 0;
+ return ops->signal_frame_p (gdbarch, this_frame);
+}
+
+/* Set the architecture-specific adjustment of .eh_frame and .debug_frame
+ register numbers. */
+
+void
+dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch,
+ int (*adjust_regnum) (struct gdbarch *,
+ int, int))
+{
+ struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ ops->adjust_regnum = adjust_regnum;
+}
+
+/* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame
+ register. */
+
+static int
+dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, int eh_frame_p)
+{
+ struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ if (ops->adjust_regnum == NULL)
+ return regnum;
+ return ops->adjust_regnum (gdbarch, regnum, eh_frame_p);
+}
+
+static void
+dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs,
+ struct dwarf2_fde *fde)
+{
+ static const char *arm_idents[] = {
+ "ARM C Compiler, ADS",
+ "Thumb C Compiler, ADS",
+ "ARM C++ Compiler, ADS",
+ "Thumb C++ Compiler, ADS",
+ "ARM/Thumb C/C++ Compiler, RVCT"
+ };
+ int i;
+
+ struct symtab *s;
+
+ s = find_pc_symtab (fs->pc);
+ if (s == NULL || s->producer == NULL)
+ return;
+
+ for (i = 0; i < ARRAY_SIZE (arm_idents); i++)
+ if (strncmp (s->producer, arm_idents[i], strlen (arm_idents[i])) == 0)
+ {
+ if (fde->cie->version == 1)
+ fs->armcc_cfa_offsets_sf = 1;
+
+ if (fde->cie->version == 1)
+ fs->armcc_cfa_offsets_reversed = 1;
+
+ /* The reversed offset problem is present in some compilers
+ using DWARF3, but it was eventually fixed. Check the ARM
+ defined augmentations, which are in the format "armcc" followed
+ by a list of one-character options. The "+" option means
+ this problem is fixed (no quirk needed). If the armcc
+ augmentation is missing, the quirk is needed. */
+ if (fde->cie->version == 3
+ && (strncmp (fde->cie->augmentation, "armcc", 5) != 0
+ || strchr (fde->cie->augmentation + 5, '+') == NULL))
+ fs->armcc_cfa_offsets_reversed = 1;
+
+ return;
+ }
+}
+\f
struct dwarf2_frame_cache
{
/* DWARF Call Frame Address. */
CORE_ADDR cfa;
+ /* Set if the return address column was marked as undefined. */
+ int undefined_retaddr;
+
/* Saved registers, indexed by GDB register number, not by DWARF
register number. */
struct dwarf2_frame_state_reg *reg;
+
+ /* Return address register. */
+ struct dwarf2_frame_state_reg retaddr_reg;
+
+ /* Target address size in bytes. */
+ int addr_size;
};
static struct dwarf2_frame_cache *
-dwarf2_frame_cache (struct frame_info *next_frame, void **this_cache)
+dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache)
{
struct cleanup *old_chain;
- int num_regs = NUM_REGS + NUM_PSEUDO_REGS;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ const int num_regs = gdbarch_num_regs (gdbarch)
+ + gdbarch_num_pseudo_regs (gdbarch);
struct dwarf2_frame_cache *cache;
struct dwarf2_frame_state *fs;
struct dwarf2_fde *fde;
- int reg;
if (*this_cache)
return *this_cache;
/* Unwind the PC.
- Note that if NEXT_FRAME is never supposed to return (i.e. a call
+ Note that if the next frame is never supposed to return (i.e. a call
to abort), the compiler might optimize away the instruction at
- NEXT_FRAME's return address. As a result the return address will
+ its return address. As a result the return address will
point at some random instruction, and the CFI for that
- instruction is probably wortless to us. GCC's unwinder solves
+ instruction is probably worthless to us. GCC's unwinder solves
this problem by substracting 1 from the return address to get an
address in the middle of a presumed call instruction (or the
instruction in the associated delay slot). This should only be
done for "normal" frames and not for resume-type frames (signal
- handlers, sentinel frames, dummy frames).
-
- We don't do what GCC's does here (yet). It's not clear how
- reliable the method is. There's also a problem with finding the
- right FDE; see the comment in dwarf_frame_p. If dwarf_frame_p
- selected this frame unwinder because it found the FDE for the
- next function, using the adjusted return address might not yield
- a FDE at all. The problem isn't specific to DWARF CFI; other
- unwinders loose in similar ways. Therefore it's probably
- acceptable to leave things slightly broken for now. */
- fs->pc = frame_pc_unwind (next_frame);
+ handlers, sentinel frames, dummy frames). The function
+ get_frame_address_in_block does just this. It's not clear how
+ reliable the method is though; there is the potential for the
+ register state pre-call being different to that on return. */
+ fs->pc = get_frame_address_in_block (this_frame);
/* Find the correct FDE. */
fde = dwarf2_frame_find_fde (&fs->pc);
fs->data_align = fde->cie->data_alignment_factor;
fs->code_align = fde->cie->code_alignment_factor;
fs->retaddr_column = fde->cie->return_address_register;
+ cache->addr_size = fde->cie->addr_size;
+
+ /* Check for "quirks" - known bugs in producers. */
+ dwarf2_frame_find_quirks (fs, fde);
/* First decode all the insns in the CIE. */
- execute_cfa_program (fde->cie->initial_instructions,
- fde->cie->end, next_frame, fs);
+ execute_cfa_program (fde, fde->cie->initial_instructions,
+ fde->cie->end, this_frame, fs);
/* Save the initialized register set. */
fs->initial = fs->regs;
fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs);
/* Then decode the insns in the FDE up to our target PC. */
- execute_cfa_program (fde->instructions, fde->end, next_frame, fs);
+ execute_cfa_program (fde, fde->instructions, fde->end, this_frame, fs);
- /* Caclulate the CFA. */
+ /* Calculate the CFA. */
switch (fs->cfa_how)
{
case CFA_REG_OFFSET:
- cache->cfa = read_reg (next_frame, fs->cfa_reg);
- cache->cfa += fs->cfa_offset;
+ cache->cfa = read_reg (this_frame, fs->cfa_reg);
+ if (fs->armcc_cfa_offsets_reversed)
+ cache->cfa -= fs->cfa_offset;
+ else
+ cache->cfa += fs->cfa_offset;
break;
case CFA_EXP:
cache->cfa =
- execute_stack_op (fs->cfa_exp, fs->cfa_exp_len, next_frame, 0);
+ execute_stack_op (fs->cfa_exp, fs->cfa_exp_len,
+ cache->addr_size, this_frame, 0);
break;
default:
- internal_error (__FILE__, __LINE__, "Unknown CFA rule.");
+ internal_error (__FILE__, __LINE__, _("Unknown CFA rule."));
}
- /* Save the register info in the cache. */
- for (reg = 0; reg < fs->regs.num_regs; reg++)
- {
- int regnum;
-
- /* Skip the return address column. */
- if (reg == fs->retaddr_column)
- /* NOTE: cagney/2003-06-07: Is this right? What if the
- RETADDR_COLUM corresponds to a real register (and, worse,
- that isn't the PC_REGNUM)? I'm guessing that the PC_REGNUM
- further down is trying to handle this. That can't be right
- though - PC_REGNUM may not be valid (it can be -ve). I
- think, instead when RETADDR_COLUM isn't a real register, it
- should map itself onto frame_pc_unwind. */
- continue;
+ /* Initialize the register state. */
+ {
+ int regnum;
+
+ for (regnum = 0; regnum < num_regs; regnum++)
+ dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame);
+ }
+
+ /* Go through the DWARF2 CFI generated table and save its register
+ location information in the cache. Note that we don't skip the
+ return address column; it's perfectly all right for it to
+ correspond to a real register. If it doesn't correspond to a
+ real register, or if we shouldn't treat it as such,
+ gdbarch_dwarf2_reg_to_regnum should be defined to return a number outside
+ the range [0, gdbarch_num_regs). */
+ {
+ int column; /* CFI speak for "register number". */
- /* Use the GDB register number as index. */
- regnum = DWARF2_REG_TO_REGNUM (reg);
+ for (column = 0; column < fs->regs.num_regs; column++)
+ {
+ /* Use the GDB register number as the destination index. */
+ int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, column);
- if (regnum >= 0 && regnum < num_regs)
- cache->reg[regnum] = fs->regs.reg[reg];
- }
+ /* If there's no corresponding GDB register, ignore it. */
+ if (regnum < 0 || regnum >= num_regs)
+ continue;
+
+ /* NOTE: cagney/2003-09-05: CFI should specify the disposition
+ of all debug info registers. If it doesn't, complain (but
+ not too loudly). It turns out that GCC assumes that an
+ unspecified register implies "same value" when CFI (draft
+ 7) specifies nothing at all. Such a register could equally
+ be interpreted as "undefined". Also note that this check
+ isn't sufficient; it only checks that all registers in the
+ range [0 .. max column] are specified, and won't detect
+ problems when a debug info register falls outside of the
+ table. We need a way of iterating through all the valid
+ DWARF2 register numbers. */
+ if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED)
+ {
+ if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED)
+ complaint (&symfile_complaints, _("\
+incomplete CFI data; unspecified registers (e.g., %s) at 0x%s"),
+ gdbarch_register_name (gdbarch, regnum),
+ paddr_nz (fs->pc));
+ }
+ else
+ cache->reg[regnum] = fs->regs.reg[column];
+ }
+ }
+
+ /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information
+ we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */
+ {
+ int regnum;
+
+ for (regnum = 0; regnum < num_regs; regnum++)
+ {
+ if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA
+ || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET)
+ {
+ struct dwarf2_frame_state_reg *retaddr_reg =
+ &fs->regs.reg[fs->retaddr_column];
+
+ /* It seems rather bizarre to specify an "empty" column as
+ the return adress column. However, this is exactly
+ what GCC does on some targets. It turns out that GCC
+ assumes that the return address can be found in the
+ register corresponding to the return address column.
+ Incidentally, that's how we should treat a return
+ address column specifying "same value" too. */
+ if (fs->retaddr_column < fs->regs.num_regs
+ && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED
+ && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE)
+ {
+ if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA)
+ cache->reg[regnum] = *retaddr_reg;
+ else
+ cache->retaddr_reg = *retaddr_reg;
+ }
+ else
+ {
+ if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA)
+ {
+ cache->reg[regnum].loc.reg = fs->retaddr_column;
+ cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG;
+ }
+ else
+ {
+ cache->retaddr_reg.loc.reg = fs->retaddr_column;
+ cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG;
+ }
+ }
+ }
+ }
+ }
- /* Store the location of the return addess. If the return address
- column (adjusted) is not the same as gdb's PC_REGNUM, then this
- implies a copy from the ra column register. */
if (fs->retaddr_column < fs->regs.num_regs
- && fs->regs.reg[fs->retaddr_column].how != REG_UNSAVED)
- {
- /* See comment above about a possibly -ve PC_REGNUM. If this
- assertion fails, it's a problem with this code and not the
- architecture. */
- gdb_assert (PC_REGNUM >= 0);
- cache->reg[PC_REGNUM] = fs->regs.reg[fs->retaddr_column];
- }
- else
- {
- reg = DWARF2_REG_TO_REGNUM (fs->retaddr_column);
- if (reg != PC_REGNUM)
- {
- /* See comment above about PC_REGNUM being -ve. If this
- assertion fails, it's a problem with this code and not
- the architecture. */
- gdb_assert (PC_REGNUM >= 0);
- cache->reg[PC_REGNUM].loc.reg = reg;
- cache->reg[PC_REGNUM].how = REG_SAVED_REG;
- }
- }
+ && fs->regs.reg[fs->retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED)
+ cache->undefined_retaddr = 1;
do_cleanups (old_chain);
}
static void
-dwarf2_frame_this_id (struct frame_info *next_frame, void **this_cache,
+dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache,
struct frame_id *this_id)
{
struct dwarf2_frame_cache *cache =
- dwarf2_frame_cache (next_frame, this_cache);
+ dwarf2_frame_cache (this_frame, this_cache);
- (*this_id) = frame_id_build (cache->cfa, frame_func_unwind (next_frame));
+ if (cache->undefined_retaddr)
+ return;
+
+ (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame));
}
-static void
-dwarf2_frame_prev_register (struct frame_info *next_frame, void **this_cache,
- int regnum, int *optimizedp,
- enum lval_type *lvalp, CORE_ADDR *addrp,
- int *realnump, void *valuep)
+static struct value *
+dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache,
+ int regnum)
{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct dwarf2_frame_cache *cache =
- dwarf2_frame_cache (next_frame, this_cache);
+ dwarf2_frame_cache (this_frame, this_cache);
+ CORE_ADDR addr;
+ int realnum;
switch (cache->reg[regnum].how)
{
- case REG_UNSAVED:
- *optimizedp = 1;
- *lvalp = not_lval;
- *addrp = 0;
- *realnump = -1;
- if (regnum == SP_REGNUM)
- {
- /* GCC defines the CFA as the value of the stack pointer
- just before the call instruction is executed. Do other
- compilers use the same definition? */
- /* DWARF V3 Draft 7 p102: Typically, the CFA is defined to
- be the value of the stack pointer at the call site in the
- previous frame (which may be different from its value on
- entry to the current frame). */
- /* DWARF V3 Draft 7 p103: The first column of the rules
- defines the rule which computes the CFA value; it may be
- either a register and a signed offset that are added
- together or a DWARF expression that is evaluated. */
- /* FIXME: cagney/2003-07-07: I don't understand this. The
- CFI info should have provided unwind information for the
- SP register and then pointed ->cfa_reg at it, not the
- reverse. Assuming that SP_REGNUM is !-ve, there is a
- very real posibility that CFA is an offset from some
- other register, having nothing to do with the unwound SP
- value. */
- *optimizedp = 0;
- if (valuep)
- {
- /* Store the value. */
- store_typed_address (valuep, builtin_type_void_data_ptr,
- cache->cfa);
- }
- }
- else if (valuep)
- {
- /* In some cases, for example %eflags on the i386, we have
- to provide a sane value, even though this register wasn't
- saved. Assume we can get it from NEXT_FRAME. */
- frame_unwind_register (next_frame, regnum, valuep);
- }
- break;
+ case DWARF2_FRAME_REG_UNDEFINED:
+ /* If CFI explicitly specified that the value isn't defined,
+ mark it as optimized away; the value isn't available. */
+ return frame_unwind_got_optimized (this_frame, regnum);
+
+ case DWARF2_FRAME_REG_SAVED_OFFSET:
+ addr = cache->cfa + cache->reg[regnum].loc.offset;
+ return frame_unwind_got_memory (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_SAVED_REG:
+ realnum
+ = gdbarch_dwarf2_reg_to_regnum (gdbarch, cache->reg[regnum].loc.reg);
+ return frame_unwind_got_register (this_frame, regnum, realnum);
+
+ case DWARF2_FRAME_REG_SAVED_EXP:
+ addr = execute_stack_op (cache->reg[regnum].loc.exp,
+ cache->reg[regnum].exp_len,
+ cache->addr_size, this_frame, cache->cfa);
+ return frame_unwind_got_memory (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_SAVED_VAL_OFFSET:
+ addr = cache->cfa + cache->reg[regnum].loc.offset;
+ return frame_unwind_got_constant (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_SAVED_VAL_EXP:
+ addr = execute_stack_op (cache->reg[regnum].loc.exp,
+ cache->reg[regnum].exp_len,
+ cache->addr_size, this_frame, cache->cfa);
+ return frame_unwind_got_constant (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_UNSPECIFIED:
+ /* GCC, in its infinite wisdom decided to not provide unwind
+ information for registers that are "same value". Since
+ DWARF2 (3 draft 7) doesn't define such behavior, said
+ registers are actually undefined (which is different to CFI
+ "undefined"). Code above issues a complaint about this.
+ Here just fudge the books, assume GCC, and that the value is
+ more inner on the stack. */
+ return frame_unwind_got_register (this_frame, regnum, regnum);
+
+ case DWARF2_FRAME_REG_SAME_VALUE:
+ return frame_unwind_got_register (this_frame, regnum, regnum);
+
+ case DWARF2_FRAME_REG_CFA:
+ return frame_unwind_got_address (this_frame, regnum, cache->cfa);
+
+ case DWARF2_FRAME_REG_CFA_OFFSET:
+ addr = cache->cfa + cache->reg[regnum].loc.offset;
+ return frame_unwind_got_address (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_RA_OFFSET:
+ addr = cache->reg[regnum].loc.offset;
+ regnum = gdbarch_dwarf2_reg_to_regnum
+ (gdbarch, cache->retaddr_reg.loc.reg);
+ addr += get_frame_register_unsigned (this_frame, regnum);
+ return frame_unwind_got_address (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_FN:
+ return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum);
- case REG_SAVED_OFFSET:
- *optimizedp = 0;
- *lvalp = lval_memory;
- *addrp = cache->cfa + cache->reg[regnum].loc.offset;
- *realnump = -1;
- if (valuep)
- {
- /* Read the value in from memory. */
- read_memory (*addrp, valuep,
- register_size (current_gdbarch, regnum));
- }
- break;
+ default:
+ internal_error (__FILE__, __LINE__, _("Unknown register rule."));
+ }
+}
- case REG_SAVED_REG:
- regnum = DWARF2_REG_TO_REGNUM (cache->reg[regnum].loc.reg);
- frame_register_unwind (next_frame, regnum,
- optimizedp, lvalp, addrp, realnump, valuep);
- break;
+static int
+dwarf2_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame, void **this_cache)
+{
+ /* Grab an address that is guarenteed to reside somewhere within the
+ function. get_frame_pc(), with a no-return next function, can
+ end up returning something past the end of this function's body.
+ If the frame we're sniffing for is a signal frame whose start
+ address is placed on the stack by the OS, its FDE must
+ extend one byte before its start address or we could potentially
+ select the FDE of the previous function. */
+ CORE_ADDR block_addr = get_frame_address_in_block (this_frame);
+ struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr);
+ if (!fde)
+ return 0;
- case REG_SAVED_EXP:
- *optimizedp = 0;
- *lvalp = lval_memory;
- *addrp = execute_stack_op (cache->reg[regnum].loc.exp,
- cache->reg[regnum].exp_len,
- next_frame, cache->cfa);
- *realnump = -1;
- if (valuep)
- {
- /* Read the value in from memory. */
- read_memory (*addrp, valuep,
- register_size (current_gdbarch, regnum));
- }
- break;
+ /* On some targets, signal trampolines may have unwind information.
+ We need to recognize them so that we set the frame type
+ correctly. */
- case REG_UNMODIFIED:
- frame_register_unwind (next_frame, regnum,
- optimizedp, lvalp, addrp, realnump, valuep);
- break;
+ if (fde->cie->signal_frame
+ || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame),
+ this_frame))
+ return self->type == SIGTRAMP_FRAME;
- default:
- internal_error (__FILE__, __LINE__, "Unknown register rule.");
- }
+ return self->type != SIGTRAMP_FRAME;
}
static const struct frame_unwind dwarf2_frame_unwind =
{
NORMAL_FRAME,
dwarf2_frame_this_id,
- dwarf2_frame_prev_register
+ dwarf2_frame_prev_register,
+ NULL,
+ dwarf2_frame_sniffer
};
-const struct frame_unwind *
-dwarf2_frame_p (CORE_ADDR pc)
+static const struct frame_unwind dwarf2_signal_frame_unwind =
{
- /* The way GDB works, this function can be called with PC just after
- the last instruction of the function we're supposed to return the
- unwind methods for. In that case we won't find the correct FDE;
- instead we find the FDE for the next function, or we won't find
- an FDE at all. There is a possible solution (see the comment in
- dwarf2_frame_cache), GDB doesn't pass us enough information to
- implement it. */
- if (dwarf2_frame_find_fde (&pc))
- return &dwarf2_frame_unwind;
+ SIGTRAMP_FRAME,
+ dwarf2_frame_this_id,
+ dwarf2_frame_prev_register,
+ NULL,
+ dwarf2_frame_sniffer
+};
- return NULL;
+/* Append the DWARF-2 frame unwinders to GDBARCH's list. */
+
+void
+dwarf2_append_unwinders (struct gdbarch *gdbarch)
+{
+ frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind);
+ frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind);
}
\f
response to the "info frame" command. */
static CORE_ADDR
-dwarf2_frame_base_address (struct frame_info *next_frame, void **this_cache)
+dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache)
{
struct dwarf2_frame_cache *cache =
- dwarf2_frame_cache (next_frame, this_cache);
+ dwarf2_frame_cache (this_frame, this_cache);
return cache->cfa;
}
};
const struct frame_base *
-dwarf2_frame_base_p (CORE_ADDR pc)
+dwarf2_frame_base_sniffer (struct frame_info *this_frame)
{
- if (dwarf2_frame_find_fde (&pc))
+ CORE_ADDR block_addr = get_frame_address_in_block (this_frame);
+ if (dwarf2_frame_find_fde (&block_addr))
return &dwarf2_frame_base;
return NULL;
}
\f
-/* A minimal decoding of DWARF2 compilation units. We only decode
- what's needed to get to the call frame information. */
-
-struct comp_unit
-{
- /* Keep the bfd convenient. */
- bfd *abfd;
-
- struct objfile *objfile;
-
- /* Linked list of CIEs for this object. */
- struct dwarf2_cie *cie;
-
- /* Address size for this unit - from unit header. */
- unsigned char addr_size;
-
- /* Pointer to the .debug_frame section loaded into memory. */
- char *dwarf_frame_buffer;
-
- /* Length of the loaded .debug_frame section. */
- unsigned long dwarf_frame_size;
-
- /* Pointer to the .debug_frame section. */
- asection *dwarf_frame_section;
-
- /* Base for DW_EH_PE_datarel encodings. */
- bfd_vma dbase;
-};
+const struct objfile_data *dwarf2_frame_objfile_data;
static unsigned int
-read_1_byte (bfd *bfd, char *buf)
+read_1_byte (bfd *abfd, gdb_byte *buf)
{
- return bfd_get_8 (abfd, (bfd_byte *) buf);
+ return bfd_get_8 (abfd, buf);
}
static unsigned int
-read_4_bytes (bfd *abfd, char *buf)
+read_4_bytes (bfd *abfd, gdb_byte *buf)
{
- return bfd_get_32 (abfd, (bfd_byte *) buf);
+ return bfd_get_32 (abfd, buf);
}
static ULONGEST
-read_8_bytes (bfd *abfd, char *buf)
+read_8_bytes (bfd *abfd, gdb_byte *buf)
{
- return bfd_get_64 (abfd, (bfd_byte *) buf);
+ return bfd_get_64 (abfd, buf);
}
static ULONGEST
-read_unsigned_leb128 (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
+read_unsigned_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
ULONGEST result;
unsigned int num_read;
int shift;
- unsigned char byte;
+ gdb_byte byte;
result = 0;
shift = 0;
}
static LONGEST
-read_signed_leb128 (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
+read_signed_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
LONGEST result;
int shift;
unsigned int num_read;
- unsigned char byte;
+ gdb_byte byte;
result = 0;
shift = 0;
}
while (byte & 0x80);
- if ((shift < 32) && (byte & 0x40))
- result |= -(1 << shift);
+ if (shift < 8 * sizeof (result) && (byte & 0x40))
+ result |= -(((LONGEST)1) << shift);
*bytes_read_ptr = num_read;
}
static ULONGEST
-read_initial_length (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
+read_initial_length (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
LONGEST result;
- result = bfd_get_32 (abfd, (bfd_byte *) buf);
+ result = bfd_get_32 (abfd, buf);
if (result == 0xffffffff)
{
- result = bfd_get_64 (abfd, (bfd_byte *) buf + 4);
+ result = bfd_get_64 (abfd, buf + 4);
*bytes_read_ptr = 12;
}
else
position in the FDE, ...). Bit 7, indicates that the address
should be dereferenced. */
-static unsigned char
+static gdb_byte
encoding_for_size (unsigned int size)
{
switch (size)
case 8:
return DW_EH_PE_udata8;
default:
- internal_error (__FILE__, __LINE__, "Unsupported address size");
- }
-}
-
-static unsigned int
-size_of_encoded_value (unsigned char encoding)
-{
- if (encoding == DW_EH_PE_omit)
- return 0;
-
- switch (encoding & 0x07)
- {
- case DW_EH_PE_absptr:
- return TYPE_LENGTH (builtin_type_void_data_ptr);
- case DW_EH_PE_udata2:
- return 2;
- case DW_EH_PE_udata4:
- return 4;
- case DW_EH_PE_udata8:
- return 8;
- default:
- internal_error (__FILE__, __LINE__, "Invalid or unsupported encoding");
+ internal_error (__FILE__, __LINE__, _("Unsupported address size"));
}
}
static CORE_ADDR
-read_encoded_value (struct comp_unit *unit, unsigned char encoding,
- char *buf, unsigned int *bytes_read_ptr)
+read_encoded_value (struct comp_unit *unit, gdb_byte encoding,
+ int ptr_len, gdb_byte *buf, unsigned int *bytes_read_ptr,
+ CORE_ADDR func_base)
{
+ ptrdiff_t offset;
CORE_ADDR base;
/* GCC currently doesn't generate DW_EH_PE_indirect encodings for
FDE's. */
if (encoding & DW_EH_PE_indirect)
internal_error (__FILE__, __LINE__,
- "Unsupported encoding: DW_EH_PE_indirect");
+ _("Unsupported encoding: DW_EH_PE_indirect"));
+
+ *bytes_read_ptr = 0;
switch (encoding & 0x70)
{
base = 0;
break;
case DW_EH_PE_pcrel:
- base = bfd_get_section_vma (unit->bfd, unit->dwarf_frame_section);
+ base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section);
base += (buf - unit->dwarf_frame_buffer);
break;
case DW_EH_PE_datarel:
base = unit->dbase;
break;
+ case DW_EH_PE_textrel:
+ base = unit->tbase;
+ break;
+ case DW_EH_PE_funcrel:
+ base = func_base;
+ break;
+ case DW_EH_PE_aligned:
+ base = 0;
+ offset = buf - unit->dwarf_frame_buffer;
+ if ((offset % ptr_len) != 0)
+ {
+ *bytes_read_ptr = ptr_len - (offset % ptr_len);
+ buf += *bytes_read_ptr;
+ }
+ break;
default:
- internal_error (__FILE__, __LINE__, "Invalid or unsupported encoding");
+ internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding"));
}
- if ((encoding & 0x0f) == 0x00)
- encoding |= encoding_for_size (TYPE_LENGTH(builtin_type_void_data_ptr));
+ if ((encoding & 0x07) == 0x00)
+ {
+ encoding |= encoding_for_size (ptr_len);
+ if (bfd_get_sign_extend_vma (unit->abfd))
+ encoding |= DW_EH_PE_signed;
+ }
switch (encoding & 0x0f)
{
+ case DW_EH_PE_uleb128:
+ {
+ ULONGEST value;
+ gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7;
+ *bytes_read_ptr += read_uleb128 (buf, end_buf, &value) - buf;
+ return base + value;
+ }
case DW_EH_PE_udata2:
- *bytes_read_ptr = 2;
+ *bytes_read_ptr += 2;
return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf));
case DW_EH_PE_udata4:
- *bytes_read_ptr = 4;
+ *bytes_read_ptr += 4;
return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf));
case DW_EH_PE_udata8:
- *bytes_read_ptr = 8;
+ *bytes_read_ptr += 8;
return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf));
+ case DW_EH_PE_sleb128:
+ {
+ LONGEST value;
+ gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7;
+ *bytes_read_ptr += read_sleb128 (buf, end_buf, &value) - buf;
+ return base + value;
+ }
case DW_EH_PE_sdata2:
- *bytes_read_ptr = 2;
+ *bytes_read_ptr += 2;
return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf));
case DW_EH_PE_sdata4:
- *bytes_read_ptr = 4;
+ *bytes_read_ptr += 4;
return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf));
case DW_EH_PE_sdata8:
- *bytes_read_ptr = 8;
+ *bytes_read_ptr += 8;
return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf));
default:
- internal_error (__FILE__, __LINE__, "Invalid or unsupported encoding");
+ internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding"));
}
}
\f
{
cie->next = unit->cie;
unit->cie = cie;
+ cie->unit = unit;
}
/* Find the FDE for *PC. Return a pointer to the FDE, and store the
struct dwarf2_fde *fde;
CORE_ADDR offset;
+ fde = objfile_data (objfile, dwarf2_frame_objfile_data);
+ if (fde == NULL)
+ continue;
+
+ gdb_assert (objfile->section_offsets);
offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
-
- fde = objfile->sym_private;
+
while (fde)
{
if (*pc >= fde->initial_location + offset
static void
add_fde (struct comp_unit *unit, struct dwarf2_fde *fde)
{
- fde->next = unit->objfile->sym_private;
- unit->objfile->sym_private = fde;
+ fde->next = objfile_data (unit->objfile, dwarf2_frame_objfile_data);
+ set_objfile_data (unit->objfile, dwarf2_frame_objfile_data, fde);
}
#ifdef CC_HAS_LONG_LONG
#define DW64_CIE_ID ~0
#endif
-static char *decode_frame_entry (struct comp_unit *unit, char *start,
- int eh_frame_p);
+static gdb_byte *decode_frame_entry (struct comp_unit *unit, gdb_byte *start,
+ int eh_frame_p);
/* Decode the next CIE or FDE. Return NULL if invalid input, otherwise
the next byte to be processed. */
-static char *
-decode_frame_entry_1 (struct comp_unit *unit, char *start, int eh_frame_p)
+static gdb_byte *
+decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p)
{
- char *buf;
+ struct gdbarch *gdbarch = get_objfile_arch (unit->objfile);
+ gdb_byte *buf, *end;
LONGEST length;
unsigned int bytes_read;
int dwarf64_p;
ULONGEST cie_id;
ULONGEST cie_pointer;
- char *end;
buf = start;
length = read_initial_length (unit->abfd, buf, &bytes_read);
/* This is a CIE. */
struct dwarf2_cie *cie;
char *augmentation;
+ unsigned int cie_version;
/* Record the offset into the .debug_frame section of this CIE. */
cie_pointer = start - unit->dwarf_frame_buffer;
return end;
cie = (struct dwarf2_cie *)
- obstack_alloc (&unit->objfile->psymbol_obstack,
+ obstack_alloc (&unit->objfile->objfile_obstack,
sizeof (struct dwarf2_cie));
cie->initial_instructions = NULL;
cie->cie_pointer = cie_pointer;
/* The encoding for FDE's in a normal .debug_frame section
- depends on the target address size as specified in the
- Compilation Unit Header. */
- cie->encoding = encoding_for_size (unit->addr_size);
+ depends on the target address size. */
+ cie->encoding = DW_EH_PE_absptr;
+
+ /* The target address size. For .eh_frame FDEs this is considered
+ equal to the size of a target pointer. For .dwarf_frame FDEs,
+ this is supposed to be the target address size from the associated
+ CU header. FIXME: We do not have a good way to determine the
+ latter. Always use the target pointer size for now. */
+ cie->addr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT;
+
+ /* We'll determine the final value later, but we need to
+ initialize it conservatively. */
+ cie->signal_frame = 0;
/* Check version number. */
- if (read_1_byte (unit->abfd, buf) != DW_CIE_VERSION)
+ cie_version = read_1_byte (unit->abfd, buf);
+ if (cie_version != 1 && cie_version != 3)
return NULL;
+ cie->version = cie_version;
buf += 1;
/* Interpret the interesting bits of the augmentation. */
- augmentation = buf;
- buf = augmentation + strlen (augmentation) + 1;
+ cie->augmentation = augmentation = (char *) buf;
+ buf += (strlen (augmentation) + 1);
+
+ /* Ignore armcc augmentations. We only use them for quirks,
+ and that doesn't happen until later. */
+ if (strncmp (augmentation, "armcc", 5) == 0)
+ augmentation += strlen (augmentation);
/* The GCC 2.x "eh" augmentation has a pointer immediately
following the augmentation string, so it must be handled
if (augmentation[0] == 'e' && augmentation[1] == 'h')
{
/* Skip. */
- buf += TYPE_LENGTH (builtin_type_void_data_ptr);
+ buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT;
augmentation += 2;
}
read_signed_leb128 (unit->abfd, buf, &bytes_read);
buf += bytes_read;
- cie->return_address_register = read_1_byte (unit->abfd, buf);
- buf += 1;
+ if (cie_version == 1)
+ {
+ cie->return_address_register = read_1_byte (unit->abfd, buf);
+ bytes_read = 1;
+ }
+ else
+ cie->return_address_register = read_unsigned_leb128 (unit->abfd, buf,
+ &bytes_read);
+ cie->return_address_register
+ = dwarf2_frame_adjust_regnum (gdbarch,
+ cie->return_address_register,
+ eh_frame_p);
+
+ buf += bytes_read;
cie->saw_z_augmentation = (*augmentation == 'z');
if (cie->saw_z_augmentation)
/* "P" indicates a personality routine in the CIE augmentation. */
else if (*augmentation == 'P')
{
- /* Skip. */
- buf += size_of_encoded_value (*buf++);
+ /* Skip. Avoid indirection since we throw away the result. */
+ gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect;
+ read_encoded_value (unit, encoding, cie->addr_size,
+ buf, &bytes_read, 0);
+ buf += bytes_read;
augmentation++;
}
- /* Otherwise we have an unknown augmentation.
- Bail out unless we saw a 'z' prefix. */
- else
+ /* "S" indicates a signal frame, such that the return
+ address must not be decremented to locate the call frame
+ info for the previous frame; it might even be the first
+ instruction of a function, so decrementing it would take
+ us to a different function. */
+ else if (*augmentation == 'S')
{
- if (cie->initial_instructions == NULL)
- return end;
+ cie->signal_frame = 1;
+ augmentation++;
+ }
- /* Skip unknown augmentations. */
- buf = cie->initial_instructions;
+ /* Otherwise we have an unknown augmentation. Assume that either
+ there is no augmentation data, or we saw a 'z' prefix. */
+ else
+ {
+ if (cie->initial_instructions)
+ buf = cie->initial_instructions;
break;
}
}
return NULL;
fde = (struct dwarf2_fde *)
- obstack_alloc (&unit->objfile->psymbol_obstack,
+ obstack_alloc (&unit->objfile->objfile_obstack,
sizeof (struct dwarf2_fde));
fde->cie = find_cie (unit, cie_pointer);
if (fde->cie == NULL)
gdb_assert (fde->cie != NULL);
fde->initial_location =
- read_encoded_value (unit, fde->cie->encoding, buf, &bytes_read);
+ read_encoded_value (unit, fde->cie->encoding, fde->cie->addr_size,
+ buf, &bytes_read, 0);
buf += bytes_read;
fde->address_range =
- read_encoded_value (unit, fde->cie->encoding & 0x0f, buf, &bytes_read);
+ read_encoded_value (unit, fde->cie->encoding & 0x0f,
+ fde->cie->addr_size, buf, &bytes_read, 0);
buf += bytes_read;
/* A 'z' augmentation in the CIE implies the presence of an
fde->instructions = buf;
fde->end = end;
+ fde->eh_frame_p = eh_frame_p;
+
add_fde (unit, fde);
}
}
/* Read a CIE or FDE in BUF and decode it. */
-static char *
-decode_frame_entry (struct comp_unit *unit, char *start, int eh_frame_p)
+static gdb_byte *
+decode_frame_entry (struct comp_unit *unit, gdb_byte *start, int eh_frame_p)
{
enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE;
- char *ret;
+ gdb_byte *ret;
const char *msg;
ptrdiff_t start_offset;
case ALIGN4:
complaint (&symfile_complaints,
- "Corrupt data in %s:%s; align 4 workaround apparently succeeded",
+ _("Corrupt data in %s:%s; align 4 workaround apparently succeeded"),
unit->dwarf_frame_section->owner->filename,
unit->dwarf_frame_section->name);
break;
case ALIGN8:
complaint (&symfile_complaints,
- "Corrupt data in %s:%s; align 8 workaround apparently succeeded",
+ _("Corrupt data in %s:%s; align 8 workaround apparently succeeded"),
unit->dwarf_frame_section->owner->filename,
unit->dwarf_frame_section->name);
break;
default:
complaint (&symfile_complaints,
- "Corrupt data in %s:%s",
+ _("Corrupt data in %s:%s"),
unit->dwarf_frame_section->owner->filename,
unit->dwarf_frame_section->name);
break;
return ret;
}
-
\f
/* FIXME: kettenis/20030504: This still needs to be integrated with
dwarf2read.c in a better way. */
/* Imported from dwarf2read.c. */
-extern file_ptr dwarf_frame_offset;
-extern unsigned int dwarf_frame_size;
extern asection *dwarf_frame_section;
-extern file_ptr dwarf_eh_frame_offset;
-extern unsigned int dwarf_eh_frame_size;
extern asection *dwarf_eh_frame_section;
/* Imported from dwarf2read.c. */
-extern char *dwarf2_read_section (struct objfile *objfile, file_ptr offset,
- unsigned int size, asection *sectp);
+extern gdb_byte *dwarf2_read_section (struct objfile *objfile, asection *sectp);
void
dwarf2_build_frame_info (struct objfile *objfile)
{
- struct comp_unit unit;
- char *frame_ptr;
+ struct comp_unit *unit;
+ gdb_byte *frame_ptr;
/* Build a minimal decoding of the DWARF2 compilation unit. */
- unit.abfd = objfile->obfd;
- unit.objfile = objfile;
- unit.addr_size = objfile->obfd->arch_info->bits_per_address / 8;
- unit.dbase = 0;
+ unit = (struct comp_unit *) obstack_alloc (&objfile->objfile_obstack,
+ sizeof (struct comp_unit));
+ unit->abfd = objfile->obfd;
+ unit->objfile = objfile;
+ unit->dbase = 0;
+ unit->tbase = 0;
/* First add the information from the .eh_frame section. That way,
the FDEs from that section are searched last. */
- if (dwarf_eh_frame_offset)
+ if (dwarf_eh_frame_section)
{
- asection *got;
+ asection *got, *txt;
- unit.cie = NULL;
- unit.dwarf_frame_buffer = dwarf2_read_section (objfile,
- dwarf_eh_frame_offset,
- dwarf_eh_frame_size,
- dwarf_eh_frame_section);
+ unit->cie = NULL;
+ unit->dwarf_frame_buffer = dwarf2_read_section (objfile,
+ dwarf_eh_frame_section);
- unit.dwarf_frame_size = dwarf_eh_frame_size;
- unit.dwarf_frame_section = dwarf_eh_frame_section;
+ unit->dwarf_frame_size = bfd_get_section_size (dwarf_eh_frame_section);
+ unit->dwarf_frame_section = dwarf_eh_frame_section;
/* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base
- that for the i386/amd64 target, which currently is the only
- target in GCC that supports/uses the DW_EH_PE_datarel
- encoding. */
- got = bfd_get_section_by_name (unit.abfd, ".got");
+ that is used for the i386/amd64 target, which currently is
+ the only target in GCC that supports/uses the
+ DW_EH_PE_datarel encoding. */
+ got = bfd_get_section_by_name (unit->abfd, ".got");
if (got)
- unit.dbase = got->vma;
+ unit->dbase = got->vma;
- frame_ptr = unit.dwarf_frame_buffer;
- while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size)
- frame_ptr = decode_frame_entry (&unit, frame_ptr, 1);
+ /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64
+ so far. */
+ txt = bfd_get_section_by_name (unit->abfd, ".text");
+ if (txt)
+ unit->tbase = txt->vma;
+
+ frame_ptr = unit->dwarf_frame_buffer;
+ while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size)
+ frame_ptr = decode_frame_entry (unit, frame_ptr, 1);
}
- if (dwarf_frame_offset)
+ if (dwarf_frame_section)
{
- unit.cie = NULL;
- unit.dwarf_frame_buffer = dwarf2_read_section (objfile,
- dwarf_frame_offset,
- dwarf_frame_size,
- dwarf_frame_section);
- unit.dwarf_frame_size = dwarf_frame_size;
- unit.dwarf_frame_section = dwarf_frame_section;
-
- frame_ptr = unit.dwarf_frame_buffer;
- while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size)
- frame_ptr = decode_frame_entry (&unit, frame_ptr, 0);
+ unit->cie = NULL;
+ unit->dwarf_frame_buffer = dwarf2_read_section (objfile,
+ dwarf_frame_section);
+ unit->dwarf_frame_size = bfd_get_section_size (dwarf_frame_section);
+ unit->dwarf_frame_section = dwarf_frame_section;
+
+ frame_ptr = unit->dwarf_frame_buffer;
+ while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size)
+ frame_ptr = decode_frame_entry (unit, frame_ptr, 0);
}
}
+
+/* Provide a prototype to silence -Wmissing-prototypes. */
+void _initialize_dwarf2_frame (void);
+
+void
+_initialize_dwarf2_frame (void)
+{
+ dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init);
+ dwarf2_frame_objfile_data = register_objfile_data ();
+}
projects / deliverable / binutils-gdb.git / blobdiff