Boston, MA 02111-1307, USA. */
#include "defs.h"
-#include "gdb_string.h"
+#include "arch-utils.h"
+#include "command.h"
+#include "dummy-frame.h"
+#include "dwarf2-frame.h"
+#include "doublest.h"
+#include "floatformat.h"
#include "frame.h"
+#include "frame-base.h"
+#include "frame-unwind.h"
#include "inferior.h"
+#include "gdbcmd.h"
#include "gdbcore.h"
#include "objfiles.h"
-#include "target.h"
-#include "floatformat.h"
+#include "osabi.h"
+#include "regcache.h"
+#include "reggroups.h"
#include "symfile.h"
#include "symtab.h"
-#include "gdbcmd.h"
-#include "command.h"
-#include "arch-utils.h"
-#include "regcache.h"
-#include "doublest.h"
+#include "target.h"
#include "value.h"
+#include "dis-asm.h"
+
#include "gdb_assert.h"
-#include "reggroups.h"
-#include "dummy-frame.h"
-#include "osabi.h"
+#include "gdb_string.h"
#include "i386-tdep.h"
#include "i387-tdep.h"
const char *
i386_register_name (int reg)
{
- if (reg >= 0 && reg < i386_num_register_names)
- return i386_register_names[reg];
-
if (i386_mmx_regnum_p (reg))
return i386_mmx_names[reg - MM0_REGNUM];
+ if (reg >= 0 && reg < i386_num_register_names)
+ return i386_register_names[reg];
+
return NULL;
}
/* This implements what GCC calls the "default" register map. */
if (reg >= 0 && reg <= 7)
{
- /* General registers. */
+ /* General-purpose registers. */
return reg;
}
else if (reg >= 12 && reg <= 19)
numbers the floating point registers differently. */
if (reg >= 0 && reg <= 9)
{
- /* General registers. */
+ /* General-purpose registers. */
return reg;
}
else if (reg >= 11 && reg <= 18)
NULL
};
static const char *disassembly_flavor = att_flavor;
+\f
-/* Stdio style buffering was used to minimize calls to ptrace, but
- this buffering did not take into account that the code section
- being accessed may not be an even number of buffers long (even if
- the buffer is only sizeof(int) long). In cases where the code
- section size happened to be a non-integral number of buffers long,
- attempting to read the last buffer would fail. Simply using
- target_read_memory and ignoring errors, rather than read_memory, is
- not the correct solution, since legitimate access errors would then
- be totally ignored. To properly handle this situation and continue
- to use buffering would require that this code be able to determine
- the minimum code section size granularity (not the alignment of the
- section itself, since the actual failing case that pointed out this
- problem had a section alignment of 4 but was not a multiple of 4
- bytes long), on a target by target basis, and then adjust it's
- buffer size accordingly. This is messy, but potentially feasible.
- It probably needs the bfd library's help and support. For now, the
- buffer size is set to 1. (FIXME -fnf) */
-
-#define CODESTREAM_BUFSIZ 1 /* Was sizeof(int), see note above. */
-static CORE_ADDR codestream_next_addr;
-static CORE_ADDR codestream_addr;
-static unsigned char codestream_buf[CODESTREAM_BUFSIZ];
-static int codestream_off;
-static int codestream_cnt;
-
-#define codestream_tell() (codestream_addr + codestream_off)
-#define codestream_peek() \
- (codestream_cnt == 0 ? \
- codestream_fill(1) : codestream_buf[codestream_off])
-#define codestream_get() \
- (codestream_cnt-- == 0 ? \
- codestream_fill(0) : codestream_buf[codestream_off++])
-
-static unsigned char
-codestream_fill (int peek_flag)
-{
- codestream_addr = codestream_next_addr;
- codestream_next_addr += CODESTREAM_BUFSIZ;
- codestream_off = 0;
- codestream_cnt = CODESTREAM_BUFSIZ;
- read_memory (codestream_addr, (char *) codestream_buf, CODESTREAM_BUFSIZ);
-
- if (peek_flag)
- return (codestream_peek ());
- else
- return (codestream_get ());
-}
+/* Use the program counter to determine the contents and size of a
+ breakpoint instruction. Return a pointer to a string of bytes that
+ encode a breakpoint instruction, store the length of the string in
+ *LEN and optionally adjust *PC to point to the correct memory
+ location for inserting the breakpoint.
-static void
-codestream_seek (CORE_ADDR place)
-{
- codestream_next_addr = place / CODESTREAM_BUFSIZ;
- codestream_next_addr *= CODESTREAM_BUFSIZ;
- codestream_cnt = 0;
- codestream_fill (1);
- while (codestream_tell () != place)
- codestream_get ();
-}
+ On the i386 we have a single breakpoint that fits in a single byte
+ and can be inserted anywhere.
-static void
-codestream_read (unsigned char *buf, int count)
+ This function is 64-bit safe. */
+
+static const unsigned char *
+i386_breakpoint_from_pc (CORE_ADDR *pc, int *len)
{
- unsigned char *p;
- int i;
- p = buf;
- for (i = 0; i < count; i++)
- *p++ = codestream_get ();
+ static unsigned char break_insn[] = { 0xcc }; /* int 3 */
+
+ *len = sizeof (break_insn);
+ return break_insn;
}
\f
+#ifdef I386_REGNO_TO_SYMMETRY
+#error "The Sequent Symmetry is no longer supported."
+#endif
-/* If the next instruction is a jump, move to its target. */
+/* According to the System V ABI, the registers %ebp, %ebx, %edi, %esi
+ and %esp "belong" to the calling function. Therefore these
+ registers should be saved if they're going to be modified. */
-static void
-i386_follow_jump (void)
+/* The maximum number of saved registers. This should include all
+ registers mentioned above, and %eip. */
+#define I386_NUM_SAVED_REGS I386_NUM_GREGS
+
+struct i386_frame_cache
{
- unsigned char buf[4];
- long delta;
+ /* Base address. */
+ CORE_ADDR base;
+ CORE_ADDR sp_offset;
+ CORE_ADDR pc;
+
+ /* Saved registers. */
+ CORE_ADDR saved_regs[I386_NUM_SAVED_REGS];
+ CORE_ADDR saved_sp;
+ int pc_in_eax;
+
+ /* Stack space reserved for local variables. */
+ long locals;
+};
+
+/* Allocate and initialize a frame cache. */
+
+static struct i386_frame_cache *
+i386_alloc_frame_cache (void)
+{
+ struct i386_frame_cache *cache;
+ int i;
+
+ cache = FRAME_OBSTACK_ZALLOC (struct i386_frame_cache);
+
+ /* Base address. */
+ cache->base = 0;
+ cache->sp_offset = -4;
+ cache->pc = 0;
- int data16;
- CORE_ADDR pos;
+ /* Saved registers. We initialize these to -1 since zero is a valid
+ offset (that's where %ebp is supposed to be stored). */
+ for (i = 0; i < I386_NUM_SAVED_REGS; i++)
+ cache->saved_regs[i] = -1;
+ cache->saved_sp = 0;
+ cache->pc_in_eax = 0;
- pos = codestream_tell ();
+ /* Frameless until proven otherwise. */
+ cache->locals = -1;
- data16 = 0;
- if (codestream_peek () == 0x66)
+ return cache;
+}
+
+/* If the instruction at PC is a jump, return the address of its
+ target. Otherwise, return PC. */
+
+static CORE_ADDR
+i386_follow_jump (CORE_ADDR pc)
+{
+ unsigned char op;
+ long delta = 0;
+ int data16 = 0;
+
+ op = read_memory_unsigned_integer (pc, 1);
+ if (op == 0x66)
{
- codestream_get ();
data16 = 1;
+ op = read_memory_unsigned_integer (pc + 1, 1);
}
- switch (codestream_get ())
+ switch (op)
{
case 0xe9:
/* Relative jump: if data16 == 0, disp32, else disp16. */
if (data16)
{
- codestream_read (buf, 2);
- delta = extract_signed_integer (buf, 2);
+ delta = read_memory_integer (pc + 2, 2);
/* Include the size of the jmp instruction (including the
0x66 prefix). */
- pos += delta + 4;
+ delta += 4;
}
else
{
- codestream_read (buf, 4);
- delta = extract_signed_integer (buf, 4);
+ delta = read_memory_integer (pc + 1, 4);
- pos += delta + 5;
+ /* Include the size of the jmp instruction. */
+ delta += 5;
}
break;
case 0xeb:
/* Relative jump, disp8 (ignore data16). */
- codestream_read (buf, 1);
- /* Sign-extend it. */
- delta = extract_signed_integer (buf, 1);
+ delta = read_memory_integer (pc + data16 + 1, 1);
- pos += delta + 2;
+ delta += data16 + 2;
break;
}
- codestream_seek (pos);
-}
-/* Find & return the amount a local space allocated, and advance the
- codestream to the first register push (if any).
+ return pc + delta;
+}
- If the entry sequence doesn't make sense, return -1, and leave
- codestream pointer at a random spot. */
+/* Check whether PC points at a prologue for a function returning a
+ structure or union. If so, it updates CACHE and returns the
+ address of the first instruction after the code sequence that
+ removes the "hidden" argument from the stack or CURRENT_PC,
+ whichever is smaller. Otherwise, return PC. */
-static long
-i386_get_frame_setup (CORE_ADDR pc)
+static CORE_ADDR
+i386_analyze_struct_return (CORE_ADDR pc, CORE_ADDR current_pc,
+ struct i386_frame_cache *cache)
{
+ /* Functions that return a structure or union start with:
+
+ popl %eax 0x58
+ xchgl %eax, (%esp) 0x87 0x04 0x24
+ or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00
+
+ (the System V compiler puts out the second `xchg' instruction,
+ and the assembler doesn't try to optimize it, so the 'sib' form
+ gets generated). This sequence is used to get the address of the
+ return buffer for a function that returns a structure. */
+ static unsigned char proto1[3] = { 0x87, 0x04, 0x24 };
+ static unsigned char proto2[4] = { 0x87, 0x44, 0x24, 0x00 };
+ unsigned char buf[4];
unsigned char op;
- codestream_seek (pc);
+ if (current_pc <= pc)
+ return pc;
+
+ op = read_memory_unsigned_integer (pc, 1);
- i386_follow_jump ();
+ if (op != 0x58) /* popl %eax */
+ return pc;
- op = codestream_get ();
+ read_memory (pc + 1, buf, 4);
+ if (memcmp (buf, proto1, 3) != 0 && memcmp (buf, proto2, 4) != 0)
+ return pc;
- if (op == 0x58) /* popl %eax */
+ if (current_pc == pc)
{
- /* This function must start with
-
- popl %eax 0x58
- xchgl %eax, (%esp) 0x87 0x04 0x24
- or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00
-
- (the System V compiler puts out the second `xchg'
- instruction, and the assembler doesn't try to optimize it, so
- the 'sib' form gets generated). This sequence is used to get
- the address of the return buffer for a function that returns
- a structure. */
- int pos;
- unsigned char buf[4];
- static unsigned char proto1[3] = { 0x87, 0x04, 0x24 };
- static unsigned char proto2[4] = { 0x87, 0x44, 0x24, 0x00 };
-
- pos = codestream_tell ();
- codestream_read (buf, 4);
- if (memcmp (buf, proto1, 3) == 0)
- pos += 3;
- else if (memcmp (buf, proto2, 4) == 0)
- pos += 4;
-
- codestream_seek (pos);
- op = codestream_get (); /* Update next opcode. */
+ cache->sp_offset += 4;
+ return current_pc;
}
- if (op == 0x68 || op == 0x6a)
+ if (current_pc == pc + 1)
{
- /* This function may start with
+ cache->pc_in_eax = 1;
+ return current_pc;
+ }
+
+ if (buf[1] == proto1[1])
+ return pc + 4;
+ else
+ return pc + 5;
+}
+
+static CORE_ADDR
+i386_skip_probe (CORE_ADDR pc)
+{
+ /* A function may start with
- pushl constant
- call _probe
- addl $4, %esp
+ pushl constant
+ call _probe
+ addl $4, %esp
- followed by
+ followed by
- pushl %ebp
+ pushl %ebp
- etc. */
- int pos;
- unsigned char buf[8];
+ etc. */
+ unsigned char buf[8];
+ unsigned char op;
+
+ op = read_memory_unsigned_integer (pc, 1);
+
+ if (op == 0x68 || op == 0x6a)
+ {
+ int delta;
- /* Skip past the `pushl' instruction; it has either a one-byte
- or a four-byte operand, depending on the opcode. */
- pos = codestream_tell ();
+ /* Skip past the `pushl' instruction; it has either a one-byte or a
+ four-byte operand, depending on the opcode. */
if (op == 0x68)
- pos += 4;
+ delta = 5;
else
- pos += 1;
- codestream_seek (pos);
+ delta = 2;
- /* Read the following 8 bytes, which should be "call _probe" (6
- bytes) followed by "addl $4,%esp" (2 bytes). */
- codestream_read (buf, sizeof (buf));
+ /* Read the following 8 bytes, which should be `call _probe' (6
+ bytes) followed by `addl $4,%esp' (2 bytes). */
+ read_memory (pc + delta, buf, sizeof (buf));
if (buf[0] == 0xe8 && buf[6] == 0xc4 && buf[7] == 0x4)
- pos += sizeof (buf);
- codestream_seek (pos);
- op = codestream_get (); /* Update next opcode. */
+ pc += delta + sizeof (buf);
}
+ return pc;
+}
+
+/* Check whether PC points at a code that sets up a new stack frame.
+ If so, it updates CACHE and returns the address of the first
+ instruction after the sequence that sets removes the "hidden"
+ argument from the stack or CURRENT_PC, whichever is smaller.
+ Otherwise, return PC. */
+
+static CORE_ADDR
+i386_analyze_frame_setup (CORE_ADDR pc, CORE_ADDR current_pc,
+ struct i386_frame_cache *cache)
+{
+ unsigned char op;
+ int skip = 0;
+
+ if (current_pc <= pc)
+ return current_pc;
+
+ op = read_memory_unsigned_integer (pc, 1);
+
if (op == 0x55) /* pushl %ebp */
{
- /* Check for "movl %esp, %ebp" -- can be written in two ways. */
- switch (codestream_get ())
+ /* Take into account that we've executed the `pushl %ebp' that
+ starts this instruction sequence. */
+ cache->saved_regs[I386_EBP_REGNUM] = 0;
+ cache->sp_offset += 4;
+
+ /* If that's all, return now. */
+ if (current_pc <= pc + 1)
+ return current_pc;
+
+ op = read_memory_unsigned_integer (pc + 1, 1);
+
+ /* Check for some special instructions that might be migrated
+ by GCC into the prologue. We check for
+
+ xorl %ebx, %ebx
+ xorl %ecx, %ecx
+ xorl %edx, %edx
+
+ and the equivalent
+
+ subl %ebx, %ebx
+ subl %ecx, %ecx
+ subl %edx, %edx
+
+ Make sure we only skip these instructions if we later see the
+ `movl %esp, %ebp' that actually sets up the frame. */
+ while (op == 0x29 || op == 0x31)
+ {
+ op = read_memory_unsigned_integer (pc + skip + 2, 1);
+ switch (op)
+ {
+ case 0xdb: /* %ebx */
+ case 0xc9: /* %ecx */
+ case 0xd2: /* %edx */
+ skip += 2;
+ break;
+ default:
+ return pc + 1;
+ }
+
+ op = read_memory_unsigned_integer (pc + skip + 1, 1);
+ }
+
+ /* Check for `movl %esp, %ebp' -- can be written in two ways. */
+ switch (op)
{
case 0x8b:
- if (codestream_get () != 0xec)
- return -1;
+ if (read_memory_unsigned_integer (pc + skip + 2, 1) != 0xec)
+ return pc + 1;
break;
case 0x89:
- if (codestream_get () != 0xe5)
- return -1;
+ if (read_memory_unsigned_integer (pc + skip + 2, 1) != 0xe5)
+ return pc + 1;
break;
default:
- return -1;
+ return pc + 1;
}
+
+ /* OK, we actually have a frame. We just don't know how large
+ it is yet. Set its size to zero. We'll adjust it if
+ necessary. We also now commit to skipping the special
+ instructions mentioned before. */
+ cache->locals = 0;
+ pc += skip;
+
+ /* If that's all, return now. */
+ if (current_pc <= pc + 3)
+ return current_pc;
+
/* Check for stack adjustment
- subl $XXX, %esp
+ subl $XXX, %esp
NOTE: You can't subtract a 16 bit immediate from a 32 bit
reg, so we don't have to worry about a data16 prefix. */
- op = codestream_peek ();
+ op = read_memory_unsigned_integer (pc + 3, 1);
if (op == 0x83)
{
/* `subl' with 8 bit immediate. */
- codestream_get ();
- if (codestream_get () != 0xec)
+ if (read_memory_unsigned_integer (pc + 4, 1) != 0xec)
/* Some instruction starting with 0x83 other than `subl'. */
- {
- codestream_seek (codestream_tell () - 2);
- return 0;
- }
- /* `subl' with signed byte immediate (though it wouldn't
- make sense to be negative). */
- return (codestream_get ());
+ return pc + 3;
+
+ /* `subl' with signed byte immediate (though it wouldn't make
+ sense to be negative). */
+ cache->locals = read_memory_integer (pc + 5, 1);
+ return pc + 6;
}
else if (op == 0x81)
{
- char buf[4];
/* Maybe it is `subl' with a 32 bit immedediate. */
- codestream_get ();
- if (codestream_get () != 0xec)
+ if (read_memory_unsigned_integer (pc + 4, 1) != 0xec)
/* Some instruction starting with 0x81 other than `subl'. */
- {
- codestream_seek (codestream_tell () - 2);
- return 0;
- }
+ return pc + 3;
+
/* It is `subl' with a 32 bit immediate. */
- codestream_read ((unsigned char *) buf, 4);
- return extract_signed_integer (buf, 4);
+ cache->locals = read_memory_integer (pc + 5, 4);
+ return pc + 9;
}
else
{
- return 0;
+ /* Some instruction other than `subl'. */
+ return pc + 3;
}
}
- else if (op == 0xc8)
+ else if (op == 0xc8) /* enter $XXX */
{
- char buf[2];
- /* `enter' with 16 bit unsigned immediate. */
- codestream_read ((unsigned char *) buf, 2);
- codestream_get (); /* Flush final byte of enter instruction. */
- return extract_unsigned_integer (buf, 2);
+ cache->locals = read_memory_unsigned_integer (pc + 1, 2);
+ return pc + 4;
}
- return (-1);
-}
-
-/* Signal trampolines don't have a meaningful frame. The frame
- pointer value we use is actually the frame pointer of the calling
- frame -- that is, the frame which was in progress when the signal
- trampoline was entered. GDB mostly treats this frame pointer value
- as a magic cookie. We detect the case of a signal trampoline by
- testing for get_frame_type() == SIGTRAMP_FRAME, which is set based
- on PC_IN_SIGTRAMP.
-
- When a signal trampoline is invoked from a frameless function, we
- essentially have two frameless functions in a row. In this case,
- we use the same magic cookie for three frames in a row. We detect
- this case by seeing whether the next frame is a SIGTRAMP_FRAME,
- and, if it does, checking whether the current frame is actually
- frameless. In this case, we need to get the PC by looking at the
- SP register value stored in the signal context.
-
- This should work in most cases except in horrible situations where
- a signal occurs just as we enter a function but before the frame
- has been set up. Incidentally, that's just what happens when we
- call a function from GDB with a signal pending (there's a test in
- the testsuite that makes this happen). Therefore we pretend that
- we have a frameless function if we're stopped at the start of a
- function. */
-
-/* Return non-zero if we're dealing with a frameless signal, that is,
- a signal trampoline invoked from a frameless function. */
-int
-i386_frameless_signal_p (struct frame_info *frame)
-{
- return (get_next_frame (frame)
- && get_frame_type (get_next_frame (frame)) == SIGTRAMP_FRAME
- && (frameless_look_for_prologue (frame)
- || get_frame_pc (frame) == get_frame_func (frame)));
+ return pc;
}
-/* Return the chain-pointer for FRAME. In the case of the i386, the
- frame's nominal address is the address of a 4-byte word containing
- the calling frame's address. */
+/* Check whether PC points at code that saves registers on the stack.
+ If so, it updates CACHE and returns the address of the first
+ instruction after the register saves or CURRENT_PC, whichever is
+ smaller. Otherwise, return PC. */
static CORE_ADDR
-i386_frame_chain (struct frame_info *frame)
+i386_analyze_register_saves (CORE_ADDR pc, CORE_ADDR current_pc,
+ struct i386_frame_cache *cache)
{
- if (pc_in_dummy_frame (get_frame_pc (frame)))
- return get_frame_base (frame);
-
- if (get_frame_type (frame) == SIGTRAMP_FRAME
- || i386_frameless_signal_p (frame))
- return get_frame_base (frame);
-
- if (! inside_entry_file (get_frame_pc (frame)))
- return read_memory_unsigned_integer (get_frame_base (frame), 4);
-
- return 0;
-}
-
-/* Determine whether the function invocation represented by FRAME does
- not have a from on the stack associated with it. If it does not,
- return non-zero, otherwise return zero. */
-
-static int
-i386_frameless_function_invocation (struct frame_info *frame)
-{
- if (get_frame_type (frame) == SIGTRAMP_FRAME)
- return 0;
-
- return frameless_look_for_prologue (frame);
-}
-
-/* Assuming FRAME is for a sigtramp routine, return the saved program
- counter. */
-
-static CORE_ADDR
-i386_sigtramp_saved_pc (struct frame_info *frame)
-{
- struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
- CORE_ADDR addr;
-
- addr = tdep->sigcontext_addr (frame);
- return read_memory_unsigned_integer (addr + tdep->sc_pc_offset, 4);
-}
-
-/* Assuming FRAME is for a sigtramp routine, return the saved stack
- pointer. */
-
-static CORE_ADDR
-i386_sigtramp_saved_sp (struct frame_info *frame)
-{
- struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
- CORE_ADDR addr;
-
- addr = tdep->sigcontext_addr (frame);
- return read_memory_unsigned_integer (addr + tdep->sc_sp_offset, 4);
-}
-
-/* Return the saved program counter for FRAME. */
+ CORE_ADDR offset = 0;
+ unsigned char op;
+ int i;
-static CORE_ADDR
-i386_frame_saved_pc (struct frame_info *frame)
-{
- if (pc_in_dummy_frame (get_frame_pc (frame)))
+ if (cache->locals > 0)
+ offset -= cache->locals;
+ for (i = 0; i < 8 && pc < current_pc; i++)
{
- ULONGEST pc;
-
- frame_unwind_unsigned_register (frame, PC_REGNUM, &pc);
- return pc;
- }
-
- if (get_frame_type (frame) == SIGTRAMP_FRAME)
- return i386_sigtramp_saved_pc (frame);
+ op = read_memory_unsigned_integer (pc, 1);
+ if (op < 0x50 || op > 0x57)
+ break;
- if (i386_frameless_signal_p (frame))
- {
- CORE_ADDR sp = i386_sigtramp_saved_sp (get_next_frame (frame));
- return read_memory_unsigned_integer (sp, 4);
+ offset -= 4;
+ cache->saved_regs[op - 0x50] = offset;
+ cache->sp_offset += 4;
+ pc++;
}
- return read_memory_unsigned_integer (get_frame_base (frame) + 4, 4);
+ return pc;
}
-/* Immediately after a function call, return the saved pc. */
-
-static CORE_ADDR
-i386_saved_pc_after_call (struct frame_info *frame)
-{
- if (get_frame_type (frame) == SIGTRAMP_FRAME)
- return i386_sigtramp_saved_pc (frame);
-
- return read_memory_unsigned_integer (read_register (SP_REGNUM), 4);
-}
+/* Do a full analysis of the prologue at PC and update CACHE
+ accordingly. Bail out early if CURRENT_PC is reached. Return the
+ address where the analysis stopped.
-/* Parse the first few instructions the function to see what registers
- were stored.
-
We handle these cases:
The startup sequence can be at the start of the function, or the
If the setup sequence is at the end of the function, then the next
instruction will be a branch back to the start. */
-static void
-i386_frame_init_saved_regs (struct frame_info *fip)
+static CORE_ADDR
+i386_analyze_prologue (CORE_ADDR pc, CORE_ADDR current_pc,
+ struct i386_frame_cache *cache)
{
- long locals = -1;
- unsigned char op;
- CORE_ADDR addr;
- CORE_ADDR pc;
- int i;
-
- if (get_frame_saved_regs (fip))
- return;
-
- frame_saved_regs_zalloc (fip);
-
- pc = get_frame_func (fip);
- if (pc != 0)
- locals = i386_get_frame_setup (pc);
-
- if (locals >= 0)
- {
- addr = get_frame_base (fip) - 4 - locals;
- for (i = 0; i < 8; i++)
- {
- op = codestream_get ();
- if (op < 0x50 || op > 0x57)
- break;
-#ifdef I386_REGNO_TO_SYMMETRY
- /* Dynix uses different internal numbering. Ick. */
- get_frame_saved_regs (fip)[I386_REGNO_TO_SYMMETRY (op - 0x50)] = addr;
-#else
- get_frame_saved_regs (fip)[op - 0x50] = addr;
-#endif
- addr -= 4;
- }
- }
-
- get_frame_saved_regs (fip)[PC_REGNUM] = get_frame_base (fip) + 4;
- get_frame_saved_regs (fip)[DEPRECATED_FP_REGNUM] = get_frame_base (fip);
+ pc = i386_follow_jump (pc);
+ pc = i386_analyze_struct_return (pc, current_pc, cache);
+ pc = i386_skip_probe (pc);
+ pc = i386_analyze_frame_setup (pc, current_pc, cache);
+ return i386_analyze_register_saves (pc, current_pc, cache);
}
/* Return PC of first real instruction. */
static CORE_ADDR
-i386_skip_prologue (CORE_ADDR pc)
+i386_skip_prologue (CORE_ADDR start_pc)
{
- unsigned char op;
- int i;
static unsigned char pic_pat[6] =
- { 0xe8, 0, 0, 0, 0, /* call 0x0 */
- 0x5b, /* popl %ebx */
+ {
+ 0xe8, 0, 0, 0, 0, /* call 0x0 */
+ 0x5b, /* popl %ebx */
};
- CORE_ADDR pos;
-
- if (i386_get_frame_setup (pc) < 0)
- return (pc);
+ struct i386_frame_cache cache;
+ CORE_ADDR pc;
+ unsigned char op;
+ int i;
- /* Found valid frame setup -- codestream now points to start of push
- instructions for saving registers. */
+ cache.locals = -1;
+ pc = i386_analyze_prologue (start_pc, 0xffffffff, &cache);
+ if (cache.locals < 0)
+ return start_pc;
- /* Skip over register saves. */
- for (i = 0; i < 8; i++)
- {
- op = codestream_peek ();
- /* Break if not `pushl' instrunction. */
- if (op < 0x50 || op > 0x57)
- break;
- codestream_get ();
- }
+ /* Found valid frame setup. */
/* The native cc on SVR4 in -K PIC mode inserts the following code
to get the address of the global offset table (GOT) into register
- %ebx
-
+ %ebx:
+
call 0x0
popl %ebx
movl %ebx,x(%ebp) (optional)
function), so we have to skip it to get to the first real
instruction at the start of the function. */
- pos = codestream_tell ();
for (i = 0; i < 6; i++)
{
- op = codestream_get ();
+ op = read_memory_unsigned_integer (pc + i, 1);
if (pic_pat[i] != op)
break;
}
if (i == 6)
{
- unsigned char buf[4];
- long delta = 6;
+ int delta = 6;
+
+ op = read_memory_unsigned_integer (pc + delta, 1);
- op = codestream_get ();
if (op == 0x89) /* movl %ebx, x(%ebp) */
{
- op = codestream_get ();
+ op = read_memory_unsigned_integer (pc + delta + 1, 1);
+
if (op == 0x5d) /* One byte offset from %ebp. */
- {
- delta += 3;
- codestream_read (buf, 1);
- }
+ delta += 3;
else if (op == 0x9d) /* Four byte offset from %ebp. */
- {
- delta += 6;
- codestream_read (buf, 4);
- }
+ delta += 6;
else /* Unexpected instruction. */
- delta = -1;
- op = codestream_get ();
+ delta = 0;
+
+ op = read_memory_unsigned_integer (pc + delta, 1);
}
+
/* addl y,%ebx */
- if (delta > 0 && op == 0x81 && codestream_get () == 0xc3)
+ if (delta > 0 && op == 0x81
+ && read_memory_unsigned_integer (pc + delta + 1, 1) == 0xc3);
{
- pos += delta + 6;
+ pc += delta + 6;
}
}
- codestream_seek (pos);
-
- i386_follow_jump ();
- return (codestream_tell ());
+ return i386_follow_jump (pc);
}
-/* Use the program counter to determine the contents and size of a
- breakpoint instruction. Return a pointer to a string of bytes that
- encode a breakpoint instruction, store the length of the string in
- *LEN and optionally adjust *PC to point to the correct memory
- location for inserting the breakpoint.
+/* This function is 64-bit safe. */
- On the i386 we have a single breakpoint that fits in a single byte
- and can be inserted anywhere. */
-
-static const unsigned char *
-i386_breakpoint_from_pc (CORE_ADDR *pc, int *len)
+static CORE_ADDR
+i386_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
{
- static unsigned char break_insn[] = { 0xcc }; /* int 3 */
-
- *len = sizeof (break_insn);
- return break_insn;
+ char buf[8];
+
+ frame_unwind_register (next_frame, PC_REGNUM, buf);
+ return extract_typed_address (buf, builtin_type_void_func_ptr);
}
+\f
-/* Push the return address (pointing to the call dummy) onto the stack
- and return the new value for the stack pointer. */
+/* Normal frames. */
-static CORE_ADDR
-i386_push_return_address (CORE_ADDR pc, CORE_ADDR sp)
+static struct i386_frame_cache *
+i386_frame_cache (struct frame_info *next_frame, void **this_cache)
{
+ struct i386_frame_cache *cache;
char buf[4];
+ int i;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = i386_alloc_frame_cache ();
+ *this_cache = cache;
+
+ /* In principle, for normal frames, %ebp holds the frame pointer,
+ which holds the base address for the current stack frame.
+ However, for functions that don't need it, the frame pointer is
+ optional. For these "frameless" functions the frame pointer is
+ actually the frame pointer of the calling frame. Signal
+ trampolines are just a special case of a "frameless" function.
+ They (usually) share their frame pointer with the frame that was
+ in progress when the signal occurred. */
- store_unsigned_integer (buf, 4, CALL_DUMMY_ADDRESS ());
- write_memory (sp - 4, buf, 4);
- return sp - 4;
+ frame_unwind_register (next_frame, I386_EBP_REGNUM, buf);
+ cache->base = extract_unsigned_integer (buf, 4);
+ if (cache->base == 0)
+ return cache;
+
+ /* For normal frames, %eip is stored at 4(%ebp). */
+ cache->saved_regs[I386_EIP_REGNUM] = 4;
+
+ cache->pc = frame_func_unwind (next_frame);
+ if (cache->pc != 0)
+ i386_analyze_prologue (cache->pc, frame_pc_unwind (next_frame), cache);
+
+ if (cache->locals < 0)
+ {
+ /* We didn't find a valid frame, which means that CACHE->base
+ currently holds the frame pointer for our calling frame. If
+ we're at the start of a function, or somewhere half-way its
+ prologue, the function's frame probably hasn't been fully
+ setup yet. Try to reconstruct the base address for the stack
+ frame by looking at the stack pointer. For truly "frameless"
+ functions this might work too. */
+
+ frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
+ cache->base = extract_unsigned_integer (buf, 4) + cache->sp_offset;
+ }
+
+ /* Now that we have the base address for the stack frame we can
+ calculate the value of %esp in the calling frame. */
+ cache->saved_sp = cache->base + 8;
+
+ /* Adjust all the saved registers such that they contain addresses
+ instead of offsets. */
+ for (i = 0; i < I386_NUM_SAVED_REGS; i++)
+ if (cache->saved_regs[i] != -1)
+ cache->saved_regs[i] += cache->base;
+
+ return cache;
}
static void
-i386_do_pop_frame (struct frame_info *frame)
+i386_frame_this_id (struct frame_info *next_frame, void **this_cache,
+ struct frame_id *this_id)
{
- CORE_ADDR fp;
- int regnum;
- char regbuf[I386_MAX_REGISTER_SIZE];
+ struct i386_frame_cache *cache = i386_frame_cache (next_frame, this_cache);
+
+ /* This marks the outermost frame. */
+ if (cache->base == 0)
+ return;
+
+ /* See the end of i386_push_dummy_call. */
+ (*this_id) = frame_id_build (cache->base + 8, cache->pc);
+}
+
+static void
+i386_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)
+{
+ struct i386_frame_cache *cache = i386_frame_cache (next_frame, this_cache);
+
+ gdb_assert (regnum >= 0);
+
+ /* The System V ABI says that:
+
+ "The flags register contains the system flags, such as the
+ direction flag and the carry flag. The direction flag must be
+ set to the forward (that is, zero) direction before entry and
+ upon exit from a function. Other user flags have no specified
+ role in the standard calling sequence and are not preserved."
+
+ To guarantee the "upon exit" part of that statement we fake a
+ saved flags register that has its direction flag cleared.
+
+ Note that GCC doesn't seem to rely on the fact that the direction
+ flag is cleared after a function return; it always explicitly
+ clears the flag before operations where it matters.
+
+ FIXME: kettenis/20030316: I'm not quite sure whether this is the
+ right thing to do. The way we fake the flags register here makes
+ it impossible to change it. */
+
+ if (regnum == I386_EFLAGS_REGNUM)
+ {
+ *optimizedp = 0;
+ *lvalp = not_lval;
+ *addrp = 0;
+ *realnump = -1;
+ if (valuep)
+ {
+ ULONGEST val;
- fp = get_frame_base (frame);
- i386_frame_init_saved_regs (frame);
+ /* Clear the direction flag. */
+ val = frame_unwind_register_unsigned (next_frame,
+ I386_EFLAGS_REGNUM);
+ val &= ~(1 << 10);
+ store_unsigned_integer (valuep, 4, val);
+ }
+
+ return;
+ }
+
+ if (regnum == I386_EIP_REGNUM && cache->pc_in_eax)
+ {
+ frame_register_unwind (next_frame, I386_EAX_REGNUM,
+ optimizedp, lvalp, addrp, realnump, valuep);
+ return;
+ }
+
+ if (regnum == I386_ESP_REGNUM && cache->saved_sp)
+ {
+ *optimizedp = 0;
+ *lvalp = not_lval;
+ *addrp = 0;
+ *realnump = -1;
+ if (valuep)
+ {
+ /* Store the value. */
+ store_unsigned_integer (valuep, 4, cache->saved_sp);
+ }
+ return;
+ }
- for (regnum = 0; regnum < NUM_REGS; regnum++)
+ if (regnum < I386_NUM_SAVED_REGS && cache->saved_regs[regnum] != -1)
{
- CORE_ADDR addr;
- addr = get_frame_saved_regs (frame)[regnum];
- if (addr)
+ *optimizedp = 0;
+ *lvalp = lval_memory;
+ *addrp = cache->saved_regs[regnum];
+ *realnump = -1;
+ if (valuep)
{
- read_memory (addr, regbuf, REGISTER_RAW_SIZE (regnum));
- deprecated_write_register_gen (regnum, regbuf);
+ /* Read the value in from memory. */
+ read_memory (*addrp, valuep,
+ register_size (current_gdbarch, regnum));
}
+ return;
}
- write_register (DEPRECATED_FP_REGNUM, read_memory_integer (fp, 4));
- write_register (PC_REGNUM, read_memory_integer (fp + 4, 4));
- write_register (SP_REGNUM, fp + 8);
- flush_cached_frames ();
+
+ frame_register_unwind (next_frame, regnum,
+ optimizedp, lvalp, addrp, realnump, valuep);
+}
+
+static const struct frame_unwind i386_frame_unwind =
+{
+ NORMAL_FRAME,
+ i386_frame_this_id,
+ i386_frame_prev_register
+};
+
+static const struct frame_unwind *
+i386_frame_sniffer (struct frame_info *next_frame)
+{
+ return &i386_frame_unwind;
+}
+\f
+
+/* Signal trampolines. */
+
+static struct i386_frame_cache *
+i386_sigtramp_frame_cache (struct frame_info *next_frame, void **this_cache)
+{
+ struct i386_frame_cache *cache;
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ CORE_ADDR addr;
+ char buf[4];
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = i386_alloc_frame_cache ();
+
+ frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
+ cache->base = extract_unsigned_integer (buf, 4) - 4;
+
+ addr = tdep->sigcontext_addr (next_frame);
+ if (tdep->sc_reg_offset)
+ {
+ int i;
+
+ gdb_assert (tdep->sc_num_regs <= I386_NUM_SAVED_REGS);
+
+ for (i = 0; i < tdep->sc_num_regs; i++)
+ if (tdep->sc_reg_offset[i] != -1)
+ cache->saved_regs[i] = addr + tdep->sc_reg_offset[i];
+ }
+ else
+ {
+ cache->saved_regs[I386_EIP_REGNUM] = addr + tdep->sc_pc_offset;
+ cache->saved_regs[I386_ESP_REGNUM] = addr + tdep->sc_sp_offset;
+ }
+
+ *this_cache = cache;
+ return cache;
+}
+
+static void
+i386_sigtramp_frame_this_id (struct frame_info *next_frame, void **this_cache,
+ struct frame_id *this_id)
+{
+ struct i386_frame_cache *cache =
+ i386_sigtramp_frame_cache (next_frame, this_cache);
+
+ /* See the end of i386_push_dummy_call. */
+ (*this_id) = frame_id_build (cache->base + 8, frame_pc_unwind (next_frame));
}
static void
-i386_pop_frame (void)
+i386_sigtramp_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)
{
- generic_pop_current_frame (i386_do_pop_frame);
+ /* Make sure we've initialized the cache. */
+ i386_sigtramp_frame_cache (next_frame, this_cache);
+
+ i386_frame_prev_register (next_frame, this_cache, regnum,
+ optimizedp, lvalp, addrp, realnump, valuep);
+}
+
+static const struct frame_unwind i386_sigtramp_frame_unwind =
+{
+ SIGTRAMP_FRAME,
+ i386_sigtramp_frame_this_id,
+ i386_sigtramp_frame_prev_register
+};
+
+static const struct frame_unwind *
+i386_sigtramp_frame_sniffer (struct frame_info *next_frame)
+{
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ char *name;
+
+ /* We shouldn't even bother to try if the OSABI didn't register
+ a sigcontext_addr handler. */
+ if (!gdbarch_tdep (current_gdbarch)->sigcontext_addr)
+ return NULL;
+
+ find_pc_partial_function (pc, &name, NULL, NULL);
+ if (PC_IN_SIGTRAMP (pc, name))
+ return &i386_sigtramp_frame_unwind;
+
+ return NULL;
+}
+\f
+
+static CORE_ADDR
+i386_frame_base_address (struct frame_info *next_frame, void **this_cache)
+{
+ struct i386_frame_cache *cache = i386_frame_cache (next_frame, this_cache);
+
+ return cache->base;
+}
+
+static const struct frame_base i386_frame_base =
+{
+ &i386_frame_unwind,
+ i386_frame_base_address,
+ i386_frame_base_address,
+ i386_frame_base_address
+};
+
+static struct frame_id
+i386_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ char buf[4];
+ CORE_ADDR fp;
+
+ frame_unwind_register (next_frame, I386_EBP_REGNUM, buf);
+ fp = extract_unsigned_integer (buf, 4);
+
+ /* See the end of i386_push_dummy_call. */
+ return frame_id_build (fp + 8, frame_pc_unwind (next_frame));
}
\f
stack. We expect the first arg to be a pointer to the jmp_buf
structure from which we extract the address that we will land at.
This address is copied into PC. This routine returns non-zero on
- success. */
+ success.
+
+ This function is 64-bit safe. */
static int
i386_get_longjmp_target (CORE_ADDR *pc)
if (jb_pc_offset == -1)
return 0;
- sp = read_register (SP_REGNUM);
+ /* Don't use I386_ESP_REGNUM here, since this function is also used
+ for AMD64. */
+ regcache_cooked_read (current_regcache, SP_REGNUM, buf);
+ sp = extract_typed_address (buf, builtin_type_void_data_ptr);
if (target_read_memory (sp + len, buf, len))
return 0;
- jb_addr = extract_typed_address (buf, builtin_type_void_func_ptr);
+ jb_addr = extract_typed_address (buf, builtin_type_void_data_ptr);
if (target_read_memory (jb_addr + jb_pc_offset, buf, len))
return 0;
\f
static CORE_ADDR
-i386_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
- int struct_return, CORE_ADDR struct_addr)
+i386_push_dummy_call (struct gdbarch *gdbarch, CORE_ADDR func_addr,
+ struct regcache *regcache, CORE_ADDR bp_addr, int nargs,
+ struct value **args, CORE_ADDR sp, int struct_return,
+ CORE_ADDR struct_addr)
{
- sp = legacy_push_arguments (nargs, args, sp, struct_return, struct_addr);
-
- if (struct_return)
+ char buf[4];
+ int i;
+
+ /* Push arguments in reverse order. */
+ for (i = nargs - 1; i >= 0; i--)
{
- char buf[4];
+ int len = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args[i]));
+
+ /* The System V ABI says that:
+
+ "An argument's size is increased, if necessary, to make it a
+ multiple of [32-bit] words. This may require tail padding,
+ depending on the size of the argument."
+
+ This makes sure the stack says word-aligned. */
+ sp -= (len + 3) & ~3;
+ write_memory (sp, VALUE_CONTENTS_ALL (args[i]), len);
+ }
+ /* Push value address. */
+ if (struct_return)
+ {
sp -= 4;
- store_address (buf, 4, struct_addr);
+ store_unsigned_integer (buf, 4, struct_addr);
write_memory (sp, buf, 4);
}
- return sp;
+ /* Store return address. */
+ sp -= 4;
+ store_unsigned_integer (buf, 4, bp_addr);
+ write_memory (sp, buf, 4);
+
+ /* Finally, update the stack pointer... */
+ store_unsigned_integer (buf, 4, sp);
+ regcache_cooked_write (regcache, I386_ESP_REGNUM, buf);
+
+ /* ...and fake a frame pointer. */
+ regcache_cooked_write (regcache, I386_EBP_REGNUM, buf);
+
+ /* MarkK wrote: This "+ 8" is all over the place:
+ (i386_frame_this_id, i386_sigtramp_frame_this_id,
+ i386_unwind_dummy_id). It's there, since all frame unwinders for
+ a given target have to agree (within a certain margin) on the
+ defenition of the stack address of a frame. Otherwise
+ frame_id_inner() won't work correctly. Since DWARF2/GCC uses the
+ stack address *before* the function call as a frame's CFA. On
+ the i386, when %ebp is used as a frame pointer, the offset
+ between the contents %ebp and the CFA as defined by GCC. */
+ return sp + 8;
}
/* These registers are used for returning integers (and on some
targets also for returning `struct' and `union' values when their
size and alignment match an integer type). */
-#define LOW_RETURN_REGNUM 0 /* %eax */
-#define HIGH_RETURN_REGNUM 2 /* %edx */
+#define LOW_RETURN_REGNUM I386_EAX_REGNUM /* %eax */
+#define HIGH_RETURN_REGNUM I386_EDX_REGNUM /* %edx */
/* Extract from an array REGBUF containing the (raw) register state, a
function return value of TYPE, and copy that, in virtual format,
its contents to the desired type. This is probably not
exactly how it would happen on the target itself, but it is
the best we can do. */
- regcache_raw_read (regcache, FP0_REGNUM, buf);
+ regcache_raw_read (regcache, I386_ST0_REGNUM, buf);
convert_typed_floating (buf, builtin_type_i387_ext, valbuf, type);
}
else
{
- int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM);
- int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM);
+ int low_size = register_size (current_gdbarch, LOW_RETURN_REGNUM);
+ int high_size = register_size (current_gdbarch, HIGH_RETURN_REGNUM);
if (len <= low_size)
{
not exactly how it would happen on the target itself, but
it is the best we can do. */
convert_typed_floating (valbuf, type, buf, builtin_type_i387_ext);
- regcache_raw_write (regcache, FP0_REGNUM, buf);
+ regcache_raw_write (regcache, I386_ST0_REGNUM, buf);
/* Set the top of the floating-point register stack to 7. The
actual value doesn't really matter, but 7 is what a normal
}
else
{
- int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM);
- int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM);
+ int low_size = register_size (current_gdbarch, LOW_RETURN_REGNUM);
+ int high_size = register_size (current_gdbarch, HIGH_RETURN_REGNUM);
if (len <= low_size)
regcache_raw_write_part (regcache, LOW_RETURN_REGNUM, 0, len, valbuf);
static CORE_ADDR
i386_extract_struct_value_address (struct regcache *regcache)
{
- ULONGEST addr;
+ char buf[4];
- regcache_raw_read_unsigned (regcache, LOW_RETURN_REGNUM, &addr);
- return addr;
+ regcache_cooked_read (regcache, I386_EAX_REGNUM, buf);
+ return extract_unsigned_integer (buf, 4);
}
\f
static struct type *
i386_register_type (struct gdbarch *gdbarch, int regnum)
{
- if (regnum == PC_REGNUM || regnum == DEPRECATED_FP_REGNUM || regnum == SP_REGNUM)
+ if (regnum == I386_EIP_REGNUM
+ || regnum == I386_EBP_REGNUM || regnum == I386_ESP_REGNUM)
return lookup_pointer_type (builtin_type_void);
if (i386_fp_regnum_p (regnum))
}
/* Map a cooked register onto a raw register or memory. For the i386,
- the MMX registers need to be mapped onto floating-point registers. */
+ the MMX registers need to be mapped onto floating point registers. */
static int
i386_mmx_regnum_to_fp_regnum (struct regcache *regcache, int regnum)
{
if (i386_mmx_regnum_p (regnum))
{
- char *mmx_buf = alloca (MAX_REGISTER_RAW_SIZE);
+ char mmx_buf[MAX_REGISTER_SIZE];
int fpnum = i386_mmx_regnum_to_fp_regnum (regcache, regnum);
/* Extract (always little endian). */
regcache_raw_read (regcache, fpnum, mmx_buf);
- memcpy (buf, mmx_buf, REGISTER_RAW_SIZE (regnum));
+ memcpy (buf, mmx_buf, register_size (gdbarch, regnum));
}
else
regcache_raw_read (regcache, regnum, buf);
{
if (i386_mmx_regnum_p (regnum))
{
- char *mmx_buf = alloca (MAX_REGISTER_RAW_SIZE);
+ char mmx_buf[MAX_REGISTER_SIZE];
int fpnum = i386_mmx_regnum_to_fp_regnum (regcache, regnum);
/* Read ... */
regcache_raw_read (regcache, fpnum, mmx_buf);
/* ... Modify ... (always little endian). */
- memcpy (mmx_buf, buf, REGISTER_RAW_SIZE (regnum));
+ memcpy (mmx_buf, buf, register_size (gdbarch, regnum));
/* ... Write. */
regcache_raw_write (regcache, fpnum, mmx_buf);
}
else
regcache_raw_write (regcache, regnum, buf);
}
+\f
+
+/* These registers don't have pervasive standard uses. Move them to
+ i386-tdep.h if necessary. */
+
+#define I386_EBX_REGNUM 3 /* %ebx */
+#define I386_ECX_REGNUM 1 /* %ecx */
+#define I386_ESI_REGNUM 6 /* %esi */
+#define I386_EDI_REGNUM 7 /* %edi */
-/* Return true iff register REGNUM's virtual format is different from
- its raw format. Note that this definition assumes that the host
- supports IEEE 32-bit floats, since it doesn't say that SSE
- registers need conversion. Even if we can't find a counterexample,
- this is still sloppy. */
+/* Return the register number of the register allocated by GCC after
+ REGNUM, or -1 if there is no such register. */
static int
-i386_register_convertible (int regnum)
+i386_next_regnum (int regnum)
{
+ /* GCC allocates the registers in the order:
+
+ %eax, %edx, %ecx, %ebx, %esi, %edi, %ebp, %esp, ...
+
+ Since storing a variable in %esp doesn't make any sense we return
+ -1 for %ebp and for %esp itself. */
+ static int next_regnum[] =
+ {
+ I386_EDX_REGNUM, /* Slot for %eax. */
+ I386_EBX_REGNUM, /* Slot for %ecx. */
+ I386_ECX_REGNUM, /* Slot for %edx. */
+ I386_ESI_REGNUM, /* Slot for %ebx. */
+ -1, -1, /* Slots for %esp and %ebp. */
+ I386_EDI_REGNUM, /* Slot for %esi. */
+ I386_EBP_REGNUM /* Slot for %edi. */
+ };
+
+ if (regnum >= 0 && regnum < sizeof (next_regnum) / sizeof (next_regnum[0]))
+ return next_regnum[regnum];
+
+ return -1;
+}
+
+/* Return nonzero if a value of type TYPE stored in register REGNUM
+ needs any special handling. */
+
+static int
+i386_convert_register_p (int regnum, struct type *type)
+{
+ int len = TYPE_LENGTH (type);
+
+ /* Values may be spread across multiple registers. Most debugging
+ formats aren't expressive enough to specify the locations, so
+ some heuristics is involved. Right now we only handle types that
+ have a length that is a multiple of the word size, since GCC
+ doesn't seem to put any other types into registers. */
+ if (len > 4 && len % 4 == 0)
+ {
+ int last_regnum = regnum;
+
+ while (len > 4)
+ {
+ last_regnum = i386_next_regnum (last_regnum);
+ len -= 4;
+ }
+
+ if (last_regnum != -1)
+ return 1;
+ }
+
return i386_fp_regnum_p (regnum);
}
-/* Convert data from raw format for register REGNUM in buffer FROM to
- virtual format with type TYPE in buffer TO. */
+/* Read a value of type TYPE from register REGNUM in frame FRAME, and
+ return its contents in TO. */
static void
-i386_register_convert_to_virtual (int regnum, struct type *type,
- char *from, char *to)
+i386_register_to_value (struct frame_info *frame, int regnum,
+ struct type *type, void *to)
{
- gdb_assert (i386_fp_regnum_p (regnum));
+ int len = TYPE_LENGTH (type);
+ char *buf = to;
+
+ /* FIXME: kettenis/20030609: What should we do if REGNUM isn't
+ available in FRAME (i.e. if it wasn't saved)? */
- /* We only support floating-point values. */
- if (TYPE_CODE (type) != TYPE_CODE_FLT)
+ if (i386_fp_regnum_p (regnum))
{
- warning ("Cannot convert floating-point register value "
- "to non-floating-point type.");
- memset (to, 0, TYPE_LENGTH (type));
+ i387_register_to_value (frame, regnum, type, to);
return;
}
- /* Convert to TYPE. This should be a no-op if TYPE is equivalent to
- the extended floating-point format used by the FPU. */
- convert_typed_floating (from, builtin_type_i387_ext, to, type);
+ /* Read a value spread accross multiple registers. */
+
+ gdb_assert (len > 4 && len % 4 == 0);
+
+ while (len > 0)
+ {
+ gdb_assert (regnum != -1);
+ gdb_assert (register_size (current_gdbarch, regnum) == 4);
+
+ get_frame_register (frame, regnum, buf);
+ regnum = i386_next_regnum (regnum);
+ len -= 4;
+ buf += 4;
+ }
}
-/* Convert data from virtual format with type TYPE in buffer FROM to
- raw format for register REGNUM in buffer TO. */
+/* Write the contents FROM of a value of type TYPE into register
+ REGNUM in frame FRAME. */
static void
-i386_register_convert_to_raw (struct type *type, int regnum,
- char *from, char *to)
+i386_value_to_register (struct frame_info *frame, int regnum,
+ struct type *type, const void *from)
{
- gdb_assert (i386_fp_regnum_p (regnum));
+ int len = TYPE_LENGTH (type);
+ const char *buf = from;
- /* We only support floating-point values. */
- if (TYPE_CODE (type) != TYPE_CODE_FLT)
+ if (i386_fp_regnum_p (regnum))
{
- warning ("Cannot convert non-floating-point type "
- "to floating-point register value.");
- memset (to, 0, TYPE_LENGTH (type));
+ i387_value_to_register (frame, regnum, type, from);
return;
}
- /* Convert from TYPE. This should be a no-op if TYPE is equivalent
- to the extended floating-point format used by the FPU. */
- convert_typed_floating (from, type, to, builtin_type_i387_ext);
+ /* Write a value spread accross multiple registers. */
+
+ gdb_assert (len > 4 && len % 4 == 0);
+
+ while (len > 0)
+ {
+ gdb_assert (regnum != -1);
+ gdb_assert (register_size (current_gdbarch, regnum) == 4);
+
+ put_frame_register (frame, regnum, buf);
+ regnum = i386_next_regnum (regnum);
+ len -= 4;
+ buf += 4;
+ }
}
-\f
+\f
+
#ifdef STATIC_TRANSFORM_NAME
/* SunPRO encodes the static variables. This is not related to C++
deals with switching between those. */
static int
-i386_print_insn (bfd_vma pc, disassemble_info *info)
+i386_print_insn (bfd_vma pc, struct disassemble_info *info)
{
gdb_assert (disassembly_flavor == att_flavor
|| disassembly_flavor == intel_flavor);
static int
i386_svr4_pc_in_sigtramp (CORE_ADDR pc, char *name)
{
+ /* UnixWare uses _sigacthandler. The origin of the other symbols is
+ currently unknown. */
return (name && (strcmp ("_sigreturn", name) == 0
|| strcmp ("_sigacthandler", name) == 0
|| strcmp ("sigvechandler", name) == 0));
}
-/* Get address of the pushed ucontext (sigcontext) on the stack for
- all three variants of SVR4 sigtramps. */
+/* Assuming NEXT_FRAME is for a frame following a SVR4 sigtramp
+ routine, return the address of the associated sigcontext (ucontext)
+ structure. */
static CORE_ADDR
-i386_svr4_sigcontext_addr (struct frame_info *frame)
+i386_svr4_sigcontext_addr (struct frame_info *next_frame)
{
- int sigcontext_offset = -1;
- char *name = NULL;
-
- find_pc_partial_function (get_frame_pc (frame), &name, NULL, NULL);
- if (name)
- {
- if (strcmp (name, "_sigreturn") == 0)
- sigcontext_offset = 132;
- else if (strcmp (name, "_sigacthandler") == 0)
- sigcontext_offset = 80;
- else if (strcmp (name, "sigvechandler") == 0)
- sigcontext_offset = 120;
- }
+ char buf[4];
+ CORE_ADDR sp;
- gdb_assert (sigcontext_offset != -1);
+ frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
+ sp = extract_unsigned_integer (buf, 4);
- if (get_next_frame (frame))
- return get_frame_base (get_next_frame (frame)) + sigcontext_offset;
- return read_register (SP_REGNUM) + sigcontext_offset;
+ return read_memory_unsigned_integer (sp + 8, 4);
}
\f
set_gdbarch_pc_in_sigtramp (gdbarch, i386_svr4_pc_in_sigtramp);
tdep->sigcontext_addr = i386_svr4_sigcontext_addr;
- tdep->sc_pc_offset = 14 * 4;
- tdep->sc_sp_offset = 7 * 4;
+ tdep->sc_pc_offset = 36 + 14 * 4;
+ tdep->sc_sp_offset = 36 + 17 * 4;
tdep->jb_pc_offset = 20;
}
int fp_regnum_p = (i386_fp_regnum_p (regnum)
|| i386_fpc_regnum_p (regnum));
int mmx_regnum_p = (i386_mmx_regnum_p (regnum));
+
if (group == i386_mmx_reggroup)
return mmx_regnum_p;
if (group == i386_sse_reggroup)
return fp_regnum_p;
if (group == general_reggroup)
return (!fp_regnum_p && !mmx_regnum_p && !sse_regnum_p);
+
return default_register_reggroup_p (gdbarch, regnum, group);
}
+\f
+
+/* Get the ARGIth function argument for the current function. */
+
+static CORE_ADDR
+i386_fetch_pointer_argument (struct frame_info *frame, int argi,
+ struct type *type)
+{
+ CORE_ADDR sp = get_frame_register_unsigned (frame, I386_ESP_REGNUM);
+ return read_memory_unsigned_integer (sp + (4 * (argi + 1)), 4);
+}
\f
static struct gdbarch *
tdep = XMALLOC (struct gdbarch_tdep);
gdbarch = gdbarch_alloc (&info, tdep);
- /* NOTE: cagney/2002-12-06: This can be deleted when this arch is
- ready to unwind the PC first (see frame.c:get_prev_frame()). */
- set_gdbarch_deprecated_init_frame_pc (gdbarch, init_frame_pc_default);
+ /* The i386 default settings now include the SSE registers.
+ I386_NUM_XREGS includes mxcsr, and we don't want to count
+ this as one of the xmm regs -- which is why we subtract one.
+
+ Note: kevinb/2003-07-14: Whatever Mark's concerns are about the
+ FPU registers in the FIXME below apply to the SSE registers as well.
+ The only problem that I see is that these registers will show up
+ in "info all-registers" even on CPUs where they don't exist. IMO,
+ however, if it's a choice between printing them always (even when
+ they don't exist) or never showing them to the user (even when they
+ do exist), I prefer the former over the latter. Ideally, of course,
+ we'd somehow autodetect that we have them (or not) and display them
+ when we have them and suppress them when we don't.
- /* The i386 default settings don't include the SSE registers.
FIXME: kettenis/20020614: They do include the FPU registers for
now, which probably is not quite right. */
- tdep->num_xmm_regs = 0;
+ tdep->num_xmm_regs = I386_NUM_XREGS - 1;
tdep->jb_pc_offset = -1;
tdep->struct_return = pcc_struct_return;
tdep->sigtramp_start = 0;
tdep->sigtramp_end = 0;
tdep->sigcontext_addr = NULL;
+ tdep->sc_reg_offset = NULL;
tdep->sc_pc_offset = -1;
tdep->sc_sp_offset = -1;
alignment. */
set_gdbarch_long_double_bit (gdbarch, 96);
- /* NOTE: tm-i386aix.h, tm-i386bsd.h, tm-i386os9k.h, tm-ptx.h,
- tm-symmetry.h currently override this. Sigh. */
- set_gdbarch_num_regs (gdbarch, I386_NUM_GREGS + I386_NUM_FREGS);
+ /* The default ABI includes general-purpose registers,
+ floating-point registers, and the SSE registers. */
+ set_gdbarch_num_regs (gdbarch, I386_SSE_NUM_REGS);
+ set_gdbarch_register_name (gdbarch, i386_register_name);
+ set_gdbarch_register_type (gdbarch, i386_register_type);
- set_gdbarch_sp_regnum (gdbarch, 4); /* %esp */
- set_gdbarch_deprecated_fp_regnum (gdbarch, 5); /* %ebp */
- set_gdbarch_pc_regnum (gdbarch, 8); /* %eip */
- set_gdbarch_ps_regnum (gdbarch, 9); /* %eflags */
- set_gdbarch_fp0_regnum (gdbarch, 16); /* %st(0) */
+ /* Register numbers of various important registers. */
+ set_gdbarch_sp_regnum (gdbarch, I386_ESP_REGNUM); /* %esp */
+ set_gdbarch_pc_regnum (gdbarch, I386_EIP_REGNUM); /* %eip */
+ set_gdbarch_ps_regnum (gdbarch, I386_EFLAGS_REGNUM); /* %eflags */
+ set_gdbarch_fp0_regnum (gdbarch, I386_ST0_REGNUM); /* %st(0) */
/* Use the "default" register numbering scheme for stabs and COFF. */
set_gdbarch_stab_reg_to_regnum (gdbarch, i386_stab_reg_to_regnum);
/* We don't define ECOFF_REG_TO_REGNUM, since ECOFF doesn't seem to
be in use on any of the supported i386 targets. */
- set_gdbarch_register_name (gdbarch, i386_register_name);
- set_gdbarch_deprecated_register_size (gdbarch, 4);
- set_gdbarch_register_bytes (gdbarch, I386_SIZEOF_GREGS + I386_SIZEOF_FREGS);
- set_gdbarch_register_type (gdbarch, i386_register_type);
-
set_gdbarch_print_float_info (gdbarch, i387_print_float_info);
set_gdbarch_get_longjmp_target (gdbarch, i386_get_longjmp_target);
/* Call dummy code. */
- set_gdbarch_deprecated_call_dummy_words (gdbarch, NULL);
- set_gdbarch_deprecated_sizeof_call_dummy_words (gdbarch, 0);
-
- set_gdbarch_register_convertible (gdbarch, i386_register_convertible);
- set_gdbarch_register_convert_to_virtual (gdbarch,
- i386_register_convert_to_virtual);
- set_gdbarch_register_convert_to_raw (gdbarch, i386_register_convert_to_raw);
+ set_gdbarch_push_dummy_call (gdbarch, i386_push_dummy_call);
- /* "An argument's size is increased, if necessary, to make it a
- multiple of [32-bit] words. This may require tail padding,
- depending on the size of the argument" -- from the x86 ABI. */
- set_gdbarch_parm_boundary (gdbarch, 32);
+ set_gdbarch_convert_register_p (gdbarch, i386_convert_register_p);
+ set_gdbarch_register_to_value (gdbarch, i386_register_to_value);
+ set_gdbarch_value_to_register (gdbarch, i386_value_to_register);
set_gdbarch_extract_return_value (gdbarch, i386_extract_return_value);
- set_gdbarch_deprecated_push_arguments (gdbarch, i386_push_arguments);
- set_gdbarch_deprecated_push_return_address (gdbarch, i386_push_return_address);
- set_gdbarch_deprecated_pop_frame (gdbarch, i386_pop_frame);
set_gdbarch_store_return_value (gdbarch, i386_store_return_value);
set_gdbarch_extract_struct_value_address (gdbarch,
i386_extract_struct_value_address);
set_gdbarch_use_struct_convention (gdbarch, i386_use_struct_convention);
- set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, i386_frame_init_saved_regs);
set_gdbarch_skip_prologue (gdbarch, i386_skip_prologue);
/* Stack grows downward. */
set_gdbarch_decr_pc_after_break (gdbarch, 1);
set_gdbarch_function_start_offset (gdbarch, 0);
- /* The following redefines make backtracing through sigtramp work.
- They manufacture a fake sigtramp frame and obtain the saved pc in
- sigtramp from the sigcontext structure which is pushed by the
- kernel on the user stack, along with a pointer to it. */
-
set_gdbarch_frame_args_skip (gdbarch, 8);
- set_gdbarch_frameless_function_invocation (gdbarch,
- i386_frameless_function_invocation);
- set_gdbarch_deprecated_frame_chain (gdbarch, i386_frame_chain);
- set_gdbarch_deprecated_frame_saved_pc (gdbarch, i386_frame_saved_pc);
- set_gdbarch_deprecated_saved_pc_after_call (gdbarch, i386_saved_pc_after_call);
- set_gdbarch_frame_num_args (gdbarch, frame_num_args_unknown);
set_gdbarch_pc_in_sigtramp (gdbarch, i386_pc_in_sigtramp);
/* Wire in the MMX registers. */
set_gdbarch_print_insn (gdbarch, i386_print_insn);
+ set_gdbarch_unwind_dummy_id (gdbarch, i386_unwind_dummy_id);
+
+ set_gdbarch_unwind_pc (gdbarch, i386_unwind_pc);
+
/* Add the i386 register groups. */
i386_add_reggroups (gdbarch);
set_gdbarch_register_reggroup_p (gdbarch, i386_register_reggroup_p);
- /* Should be using push_dummy_call. */
- set_gdbarch_deprecated_dummy_write_sp (gdbarch, generic_target_write_sp);
+ /* Helper for function argument information. */
+ set_gdbarch_fetch_pointer_argument (gdbarch, i386_fetch_pointer_argument);
+
+ /* Hook in the DWARF CFI frame unwinder. */
+ frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer);
+
+ frame_base_set_default (gdbarch, &i386_frame_base);
/* Hook in ABI-specific overrides, if they have been registered. */
gdbarch_init_osabi (info, gdbarch);
+ frame_unwind_append_sniffer (gdbarch, i386_sigtramp_frame_sniffer);
+ frame_unwind_append_sniffer (gdbarch, i386_frame_sniffer);
+
return gdbarch;
}
projects / binutils.git / blobdiff