/* Common target dependent code for GDB on ARM systems.
- Copyright 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1997, 1998, 1999, 2000
- Free Software Foundation, Inc.
+ Copyright 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1998, 1999, 2000,
+ 2001 Free Software Foundation, Inc.
This file is part of GDB.
#include "symfile.h"
#include "gdb_string.h"
#include "coff/internal.h" /* Internal format of COFF symbols in BFD */
+#include "dis-asm.h" /* For register flavors. */
+#include <ctype.h> /* for isupper () */
+#include "regcache.h"
+
+/* Each OS has a different mechanism for accessing the various
+ registers stored in the sigcontext structure.
+
+ SIGCONTEXT_REGISTER_ADDRESS should be defined to the name (or
+ function pointer) which may be used to determine the addresses
+ of the various saved registers in the sigcontext structure.
+
+ For the ARM target, there are three parameters to this function.
+ The first is the pc value of the frame under consideration, the
+ second the stack pointer of this frame, and the last is the
+ register number to fetch.
+
+ If the tm.h file does not define this macro, then it's assumed that
+ no mechanism is needed and we define SIGCONTEXT_REGISTER_ADDRESS to
+ be 0.
+
+ When it comes time to multi-arching this code, see the identically
+ named machinery in ia64-tdep.c for an example of how it could be
+ done. It should not be necessary to modify the code below where
+ this macro is used. */
+
+#ifdef SIGCONTEXT_REGISTER_ADDRESS
+#ifndef SIGCONTEXT_REGISTER_ADDRESS_P
+#define SIGCONTEXT_REGISTER_ADDRESS_P() 1
+#endif
+#else
+#define SIGCONTEXT_REGISTER_ADDRESS(SP,PC,REG) 0
+#define SIGCONTEXT_REGISTER_ADDRESS_P() 0
+#endif
extern void _initialize_arm_tdep (void);
-/*
- The following macros are actually wrong. Neither arm nor thumb can
- or should set the lsb on addr.
- The thumb addresses are mod 2, so (addr & 2) would be a good heuristic
- to use when checking for thumb (see arm_pc_is_thumb() below).
- Unfortunately, something else depends on these (incorrect) macros, so
- fixing them actually breaks gdb. I didn't have time to investigate. Z.R.
- */
-/* Thumb function addresses are odd (bit 0 is set). Here are some
- macros to test, set, or clear bit 0 of addresses. */
-#define IS_THUMB_ADDR(addr) ((addr) & 1)
-#define MAKE_THUMB_ADDR(addr) ((addr) | 1)
-#define UNMAKE_THUMB_ADDR(addr) ((addr) & ~1)
+/* Number of different reg name sets (options). */
+static int num_flavor_options;
-/* Default register names as specified by APCS. */
-static char * atpcs_register_names[] =
-{"a1", "a2", "a3", "a4", /* 0 1 2 3 */
- "v1", "v2", "v3", "v4", /* 4 5 6 7 */
- "v5", "v6", "v7", "v8", /* 8 9 10 11 */
- "IP", "SP", "LR", "PC", /* 12 13 14 15 */
- "f0", "f1", "f2", "f3", /* 16 17 18 19 */
- "f4", "f5", "f6", "f7", /* 20 21 22 23 */
- "FPS", "PS" }; /* 24 25 */
-
-/* Alternate set of registers names used by GCC. */
-static char * additional_register_names[] =
+/* We have more registers than the disassembler as gdb can print the value
+ of special registers as well.
+ The general register names are overwritten by whatever is being used by
+ the disassembler at the moment. We also adjust the case of cpsr and fps. */
+
+/* Initial value: Register names used in ARM's ISA documentation. */
+static char * arm_register_name_strings[] =
{"r0", "r1", "r2", "r3", /* 0 1 2 3 */
"r4", "r5", "r6", "r7", /* 4 5 6 7 */
"r8", "r9", "r10", "r11", /* 8 9 10 11 */
"r12", "sp", "lr", "pc", /* 12 13 14 15 */
"f0", "f1", "f2", "f3", /* 16 17 18 19 */
"f4", "f5", "f6", "f7", /* 20 21 22 23 */
- "fps", "ps" }; /* 24 25 */
-
-/* This is the variable that is set with "set disassembly-flavor".
- By default use the APCS registers names. */
-char ** arm_register_names = atpcs_register_names;
+ "fps", "cpsr" }; /* 24 25 */
+char **arm_register_names = arm_register_name_strings;
-/* Valid register name flavours. */
-static char apcs_flavor[] = "apcs";
-static char r_prefix_flavor[] = "r-prefix";
-static char * valid_flavors[] =
-{
- apcs_flavor,
- r_prefix_flavor,
- NULL
-};
+/* Valid register name flavors. */
+static const char **valid_flavors;
-/* Disassembly flavor to use. */
-static char *disassembly_flavor = apcs_flavor;
+/* Disassembly flavor to use. Default to "std" register names. */
+static const char *disassembly_flavor;
+static int current_option; /* Index to that option in the opcodes table. */
/* This is used to keep the bfd arch_info in sync with the disassembly
flavor. */
int framereg;
};
+/* Addresses for calling Thumb functions have the bit 0 set.
+ Here are some macros to test, set, or clear bit 0 of addresses. */
+#define IS_THUMB_ADDR(addr) ((addr) & 1)
+#define MAKE_THUMB_ADDR(addr) ((addr) | 1)
+#define UNMAKE_THUMB_ADDR(addr) ((addr) & ~1)
+
#define SWAP_TARGET_AND_HOST(buffer,len) \
do \
{ \
function. */
int
-arm_pc_is_thumb (bfd_vma memaddr)
+arm_pc_is_thumb (CORE_ADDR memaddr)
{
struct minimal_symbol *sym;
dummy being called from a Thumb function. */
int
-arm_pc_is_thumb_dummy (bfd_vma memaddr)
+arm_pc_is_thumb_dummy (CORE_ADDR memaddr)
{
CORE_ADDR sp = read_sp ();
- CORE_ADDR fp = read_fp ();
- if (PC_IN_CALL_DUMMY (memaddr, sp, fp))
+ /* FIXME: Until we switch for the new call dummy macros, this heuristic
+ is the best we can do. We are trying to determine if the pc is on
+ the stack, which (hopefully) will only happen in a call dummy.
+ We hope the current stack pointer is not so far alway from the dummy
+ frame location (true if we have not pushed large data structures or
+ gone too many levels deep) and that our 1024 is not enough to consider
+ code regions as part of the stack (true for most practical purposes) */
+ if (PC_IN_CALL_DUMMY (memaddr, sp, sp + 1024))
return caller_is_thumb;
else
return 0;
*/
static CORE_ADDR
-thumb_skip_prologue (CORE_ADDR pc)
+thumb_skip_prologue (CORE_ADDR pc, CORE_ADDR func_end)
{
CORE_ADDR current_pc;
int findmask = 0; /* findmask:
bit 2 - sub sp, #simm OR add sp, #simm (adjusting of sp)
*/
- for (current_pc = pc; current_pc < pc + 40; current_pc += 2)
+ for (current_pc = pc; current_pc + 2 < func_end && current_pc < pc + 40; current_pc += 2)
{
unsigned short insn = read_memory_unsigned_integer (current_pc, 2);
/* Check if this is Thumb code. */
if (arm_pc_is_thumb (pc))
- return thumb_skip_prologue (pc);
+ return thumb_skip_prologue (pc, func_end);
/* Can't find the prologue end in the symbol table, try it the hard way
by disassembling the instructions. */
fi->framereg = prologue_cache.framereg;
fi->framesize = prologue_cache.framesize;
fi->frameoffset = prologue_cache.frameoffset;
- for (i = 0; i <= NUM_REGS; i++)
+ for (i = 0; i < NUM_REGS; i++)
fi->fsr.regs[i] = prologue_cache.fsr.regs[i];
return 1;
}
prologue_cache.framesize = fi->framesize;
prologue_cache.frameoffset = fi->frameoffset;
- for (i = 0; i <= NUM_REGS; i++)
+ for (i = 0; i < NUM_REGS; i++)
prologue_cache.fsr.regs[i] = fi->fsr.regs[i];
}
the symbol table, peek in the stack frame to find the PC. */
if (find_pc_partial_function (fi->pc, NULL, &prologue_start, &prologue_end))
{
- /* Assume the prologue is everything between the first instruction
- in the function and the first source line. */
- struct symtab_and_line sal = find_pc_line (prologue_start, 0);
-
- if (sal.line == 0) /* no line info, use current PC */
- prologue_end = fi->pc;
- else if (sal.end < prologue_end) /* next line begins after fn end */
- prologue_end = sal.end; /* (probably means no prologue) */
+ /* One way to find the end of the prologue (which works well
+ for unoptimized code) is to do the following:
+
+ struct symtab_and_line sal = find_pc_line (prologue_start, 0);
+
+ if (sal.line == 0)
+ prologue_end = fi->pc;
+ else if (sal.end < prologue_end)
+ prologue_end = sal.end;
+
+ This mechanism is very accurate so long as the optimizer
+ doesn't move any instructions from the function body into the
+ prologue. If this happens, sal.end will be the last
+ instruction in the first hunk of prologue code just before
+ the first instruction that the scheduler has moved from
+ the body to the prologue.
+
+ In order to make sure that we scan all of the prologue
+ instructions, we use a slightly less accurate mechanism which
+ may scan more than necessary. To help compensate for this
+ lack of accuracy, the prologue scanning loop below contains
+ several clauses which'll cause the loop to terminate early if
+ an implausible prologue instruction is encountered.
+
+ The expression
+
+ prologue_start + 64
+
+ is a suitable endpoint since it accounts for the largest
+ possible prologue plus up to five instructions inserted by
+ the scheduler. */
+
+ if (prologue_end > prologue_start + 64)
+ {
+ prologue_end = prologue_start + 64; /* See above. */
+ }
}
else
{
PC is the address of the stmfd + 8. */
prologue_start = ADDR_BITS_REMOVE (read_memory_integer (fi->frame, 4))
- 8;
- prologue_end = prologue_start + 64; /* This is all the insn's
- that could be in the prologue,
- plus room for 5 insn's inserted
- by the scheduler. */
+ prologue_end = prologue_start + 64; /* See above. */
}
/* Now search the prologue looking for instructions that set up the
fi->fsr.regs[fp_start_reg++] = sp_offset;
}
}
+ else if ((insn & 0xf0000000) != 0xe0000000)
+ break; /* Condition not true, exit early */
+ else if ((insn & 0xfe200000) == 0xe8200000) /* ldm? */
+ break; /* Don't scan past a block load */
else
/* The optimizer might shove anything into the prologue,
so we just skip what we don't recognize. */
}
else
#endif
+
+ /* Determine whether or not we're in a sigtramp frame.
+ Unfortunately, it isn't sufficient to test
+ fi->signal_handler_caller because this value is sometimes set
+ after invoking INIT_EXTRA_FRAME_INFO. So we test *both*
+ fi->signal_handler_caller and IN_SIGTRAMP to determine if we need
+ to use the sigcontext addresses for the saved registers.
+
+ Note: If an ARM IN_SIGTRAMP method ever needs to compare against
+ the name of the function, the code below will have to be changed
+ to first fetch the name of the function and then pass this name
+ to IN_SIGTRAMP. */
+
+ if (SIGCONTEXT_REGISTER_ADDRESS_P ()
+ && (fi->signal_handler_caller || IN_SIGTRAMP (fi->pc, 0)))
+ {
+ CORE_ADDR sp;
+
+ if (!fi->next)
+ sp = read_sp();
+ else
+ sp = fi->next->frame - fi->next->frameoffset + fi->next->framesize;
+
+ for (reg = 0; reg < NUM_REGS; reg++)
+ fi->fsr.regs[reg] = SIGCONTEXT_REGISTER_ADDRESS (sp, fi->pc, reg);
+
+ /* FIXME: What about thumb mode? */
+ fi->framereg = SP_REGNUM;
+ fi->frame = read_memory_integer (fi->fsr.regs[fi->framereg], 4);
+ fi->framesize = 0;
+ fi->frameoffset = 0;
+
+ }
+ else
{
arm_scan_prologue (fi);
print_fpu_flags (status);
}
-/* If the disassembly mode is APCS, we have to also switch the
- bfd mach_type. This function is run in the set disassembly_flavor
- command, and does that. */
-
-static void
-set_disassembly_flavor_sfunc (char *args, int from_tty,
- struct cmd_list_element *c)
-{
- set_disassembly_flavor ();
-}
-
-static void
-set_disassembly_flavor (void)
-{
- if (disassembly_flavor == apcs_flavor)
- {
- parse_arm_disassembler_option ("reg-names-atpcs");
- arm_register_names = atpcs_register_names;
- }
- else if (disassembly_flavor == r_prefix_flavor)
- {
- parse_arm_disassembler_option ("reg-names-std");
- arm_register_names = additional_register_names;
- }
-}
-
-/* arm_othernames implements the "othernames" command. This is kind
- of hacky, and I prefer the set-show disassembly-flavor which is
- also used for the x86 gdb. I will keep this around, however, in
- case anyone is actually using it. */
-
-static void
-arm_othernames (char *names, int n)
-{
- if (disassembly_flavor == r_prefix_flavor)
- {
- disassembly_flavor = apcs_flavor;
- set_disassembly_flavor ();
- }
- else
- {
- disassembly_flavor = r_prefix_flavor;
- set_disassembly_flavor ();
- }
-}
-
#if 0
/* FIXME: The generated assembler works but sucks. Instead of using
r0, r1 it pushes them on the stack, then loads them into r3, r4 and
return 0; /* not a stub */
}
+/* If the user changes the register disassembly flavor used for info register
+ and other commands, we have to also switch the flavor used in opcodes
+ for disassembly output.
+ This function is run in the set disassembly_flavor command, and does that. */
+
+static void
+set_disassembly_flavor_sfunc (char *args, int from_tty,
+ struct cmd_list_element *c)
+{
+ set_disassembly_flavor ();
+}
+\f
+static void
+set_disassembly_flavor (void)
+{
+ const char *setname, *setdesc, **regnames;
+ int numregs, j;
+
+ /* Find the flavor that the user wants in the opcodes table. */
+ int current = 0;
+ numregs = get_arm_regnames (current, &setname, &setdesc, ®names);
+ while ((disassembly_flavor != setname)
+ && (current < num_flavor_options))
+ get_arm_regnames (++current, &setname, &setdesc, ®names);
+ current_option = current;
+
+ /* Fill our copy. */
+ for (j = 0; j < numregs; j++)
+ arm_register_names[j] = (char *) regnames[j];
+
+ /* Adjust case. */
+ if (isupper (*regnames[PC_REGNUM]))
+ {
+ arm_register_names[FPS_REGNUM] = "FPS";
+ arm_register_names[PS_REGNUM] = "CPSR";
+ }
+ else
+ {
+ arm_register_names[FPS_REGNUM] = "fps";
+ arm_register_names[PS_REGNUM] = "cpsr";
+ }
+
+ /* Synchronize the disassembler. */
+ set_arm_regname_option (current);
+}
+
+/* arm_othernames implements the "othernames" command. This is kind
+ of hacky, and I prefer the set-show disassembly-flavor which is
+ also used for the x86 gdb. I will keep this around, however, in
+ case anyone is actually using it. */
+
+static void
+arm_othernames (char *names, int n)
+{
+ /* Circle through the various flavors. */
+ current_option = (current_option + 1) % num_flavor_options;
+
+ disassembly_flavor = valid_flavors[current_option];
+ set_disassembly_flavor ();
+}
+
void
_initialize_arm_tdep (void)
{
+ struct ui_file *stb;
+ long length;
struct cmd_list_element *new_cmd;
+ const char *setname;
+ const char *setdesc;
+ const char **regnames;
+ int numregs, i, j;
+ static char *helptext;
tm_print_insn = gdb_print_insn_arm;
+ /* Get the number of possible sets of register names defined in opcodes. */
+ num_flavor_options = get_arm_regname_num_options ();
+
/* Sync the opcode insn printer with our register viewer: */
- parse_arm_disassembler_option ("reg-names-atpcs");
+ parse_arm_disassembler_option ("reg-names-std");
- /* Add the deprecated "othernames" command */
+ /* Begin creating the help text. */
+ stb = mem_fileopen ();
+ fprintf_unfiltered (stb, "Set the disassembly flavor.\n\
+The valid values are:\n");
- add_com ("othernames", class_obscure, arm_othernames,
- "Switch to the other set of register names.");
+ /* Initialize the array that will be passed to add_set_enum_cmd(). */
+ valid_flavors = xmalloc ((num_flavor_options + 1) * sizeof (char *));
+ for (i = 0; i < num_flavor_options; i++)
+ {
+ numregs = get_arm_regnames (i, &setname, &setdesc, ®names);
+ valid_flavors[i] = setname;
+ fprintf_unfiltered (stb, "%s - %s\n", setname,
+ setdesc);
+ /* Copy the default names (if found) and synchronize disassembler. */
+ if (!strcmp (setname, "std"))
+ {
+ disassembly_flavor = setname;
+ current_option = i;
+ for (j = 0; j < numregs; j++)
+ arm_register_names[j] = (char *) regnames[j];
+ set_arm_regname_option (i);
+ }
+ }
+ /* Mark the end of valid options. */
+ valid_flavors[num_flavor_options] = NULL;
- /* Add the disassembly-flavor command */
+ /* Finish the creation of the help text. */
+ fprintf_unfiltered (stb, "The default is \"std\".");
+ helptext = ui_file_xstrdup (stb, &length);
+ ui_file_delete (stb);
+ /* Add the disassembly-flavor command */
new_cmd = add_set_enum_cmd ("disassembly-flavor", no_class,
valid_flavors,
- (char *) &disassembly_flavor,
- "Set the disassembly flavor, \
-the valid values are \"apcs\" and \"r-prefix\", \
-and the default value is \"apcs\".",
+ &disassembly_flavor,
+ helptext,
&setlist);
new_cmd->function.sfunc = set_disassembly_flavor_sfunc;
add_show_from_set (new_cmd, &showlist);
"Set usage of ARM 32-bit mode.\n", &setlist),
&showlist);
+ /* Add the deprecated "othernames" command */
+
+ add_com ("othernames", class_obscure, arm_othernames,
+ "Switch to the next set of register names.");
}
/* Test whether the coff symbol specific value corresponds to a Thumb
projects / deliverable / binutils-gdb.git / blobdiff