1696 lines
49 KiB
C
1696 lines
49 KiB
C
/* Intel 386 target-dependent stuff.
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Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
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1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include "defs.h"
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#include "gdb_string.h"
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#include "frame.h"
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#include "inferior.h"
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#include "gdbcore.h"
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#include "objfiles.h"
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#include "target.h"
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#include "floatformat.h"
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#include "symfile.h"
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#include "symtab.h"
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#include "gdbcmd.h"
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#include "command.h"
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#include "arch-utils.h"
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#include "regcache.h"
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#include "doublest.h"
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#include "value.h"
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#include "gdb_assert.h"
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#include "reggroups.h"
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#include "dummy-frame.h"
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#include "osabi.h"
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#include "i386-tdep.h"
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#include "i387-tdep.h"
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/* Names of the registers. The first 10 registers match the register
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numbering scheme used by GCC for stabs and DWARF. */
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static char *i386_register_names[] =
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{
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"eax", "ecx", "edx", "ebx",
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"esp", "ebp", "esi", "edi",
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"eip", "eflags", "cs", "ss",
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"ds", "es", "fs", "gs",
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"st0", "st1", "st2", "st3",
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"st4", "st5", "st6", "st7",
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"fctrl", "fstat", "ftag", "fiseg",
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"fioff", "foseg", "fooff", "fop",
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"xmm0", "xmm1", "xmm2", "xmm3",
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"xmm4", "xmm5", "xmm6", "xmm7",
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"mxcsr"
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};
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/* MMX registers. */
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static char *i386_mmx_names[] =
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{
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"mm0", "mm1", "mm2", "mm3",
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"mm4", "mm5", "mm6", "mm7"
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};
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static const int mmx_num_regs = (sizeof (i386_mmx_names)
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/ sizeof (i386_mmx_names[0]));
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#define MM0_REGNUM (NUM_REGS)
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static int
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i386_mmx_regnum_p (int reg)
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{
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return (reg >= MM0_REGNUM && reg < MM0_REGNUM + mmx_num_regs);
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}
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/* FP register? */
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int
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i386_fp_regnum_p (int regnum)
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{
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return (regnum < NUM_REGS
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&& (FP0_REGNUM && FP0_REGNUM <= (regnum) && (regnum) < FPC_REGNUM));
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}
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int
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i386_fpc_regnum_p (int regnum)
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{
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return (regnum < NUM_REGS
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&& (FPC_REGNUM <= (regnum) && (regnum) < XMM0_REGNUM));
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}
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/* SSE register? */
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int
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i386_sse_regnum_p (int regnum)
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{
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return (regnum < NUM_REGS
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&& (XMM0_REGNUM <= (regnum) && (regnum) < MXCSR_REGNUM));
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}
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int
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i386_mxcsr_regnum_p (int regnum)
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{
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return (regnum < NUM_REGS
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&& (regnum == MXCSR_REGNUM));
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}
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/* Return the name of register REG. */
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const char *
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i386_register_name (int reg)
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{
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if (reg < 0)
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return NULL;
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if (i386_mmx_regnum_p (reg))
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return i386_mmx_names[reg - MM0_REGNUM];
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if (reg >= sizeof (i386_register_names) / sizeof (*i386_register_names))
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return NULL;
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return i386_register_names[reg];
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}
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/* Convert stabs register number REG to the appropriate register
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number used by GDB. */
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static int
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i386_stab_reg_to_regnum (int reg)
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{
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/* This implements what GCC calls the "default" register map. */
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if (reg >= 0 && reg <= 7)
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{
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/* General registers. */
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return reg;
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}
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else if (reg >= 12 && reg <= 19)
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{
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/* Floating-point registers. */
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return reg - 12 + FP0_REGNUM;
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}
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else if (reg >= 21 && reg <= 28)
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{
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/* SSE registers. */
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return reg - 21 + XMM0_REGNUM;
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}
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else if (reg >= 29 && reg <= 36)
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{
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/* MMX registers. */
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return reg - 29 + MM0_REGNUM;
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}
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/* This will hopefully provoke a warning. */
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return NUM_REGS + NUM_PSEUDO_REGS;
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}
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/* Convert DWARF register number REG to the appropriate register
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number used by GDB. */
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static int
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i386_dwarf_reg_to_regnum (int reg)
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{
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/* The DWARF register numbering includes %eip and %eflags, and
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numbers the floating point registers differently. */
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if (reg >= 0 && reg <= 9)
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{
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/* General registers. */
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return reg;
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}
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else if (reg >= 11 && reg <= 18)
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{
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/* Floating-point registers. */
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return reg - 11 + FP0_REGNUM;
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}
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else if (reg >= 21)
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{
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/* The SSE and MMX registers have identical numbers as in stabs. */
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return i386_stab_reg_to_regnum (reg);
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}
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/* This will hopefully provoke a warning. */
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return NUM_REGS + NUM_PSEUDO_REGS;
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}
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/* This is the variable that is set with "set disassembly-flavor", and
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its legitimate values. */
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static const char att_flavor[] = "att";
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static const char intel_flavor[] = "intel";
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static const char *valid_flavors[] =
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{
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att_flavor,
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intel_flavor,
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NULL
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};
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static const char *disassembly_flavor = att_flavor;
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/* Stdio style buffering was used to minimize calls to ptrace, but
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this buffering did not take into account that the code section
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being accessed may not be an even number of buffers long (even if
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the buffer is only sizeof(int) long). In cases where the code
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section size happened to be a non-integral number of buffers long,
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attempting to read the last buffer would fail. Simply using
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target_read_memory and ignoring errors, rather than read_memory, is
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not the correct solution, since legitimate access errors would then
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be totally ignored. To properly handle this situation and continue
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to use buffering would require that this code be able to determine
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the minimum code section size granularity (not the alignment of the
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section itself, since the actual failing case that pointed out this
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problem had a section alignment of 4 but was not a multiple of 4
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bytes long), on a target by target basis, and then adjust it's
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buffer size accordingly. This is messy, but potentially feasible.
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It probably needs the bfd library's help and support. For now, the
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buffer size is set to 1. (FIXME -fnf) */
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#define CODESTREAM_BUFSIZ 1 /* Was sizeof(int), see note above. */
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static CORE_ADDR codestream_next_addr;
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static CORE_ADDR codestream_addr;
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static unsigned char codestream_buf[CODESTREAM_BUFSIZ];
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static int codestream_off;
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static int codestream_cnt;
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#define codestream_tell() (codestream_addr + codestream_off)
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#define codestream_peek() \
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(codestream_cnt == 0 ? \
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codestream_fill(1) : codestream_buf[codestream_off])
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#define codestream_get() \
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(codestream_cnt-- == 0 ? \
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codestream_fill(0) : codestream_buf[codestream_off++])
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static unsigned char
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codestream_fill (int peek_flag)
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{
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codestream_addr = codestream_next_addr;
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codestream_next_addr += CODESTREAM_BUFSIZ;
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codestream_off = 0;
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codestream_cnt = CODESTREAM_BUFSIZ;
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read_memory (codestream_addr, (char *) codestream_buf, CODESTREAM_BUFSIZ);
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if (peek_flag)
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return (codestream_peek ());
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else
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return (codestream_get ());
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}
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static void
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codestream_seek (CORE_ADDR place)
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{
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codestream_next_addr = place / CODESTREAM_BUFSIZ;
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codestream_next_addr *= CODESTREAM_BUFSIZ;
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codestream_cnt = 0;
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codestream_fill (1);
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while (codestream_tell () != place)
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codestream_get ();
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}
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static void
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codestream_read (unsigned char *buf, int count)
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{
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unsigned char *p;
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int i;
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p = buf;
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for (i = 0; i < count; i++)
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*p++ = codestream_get ();
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}
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/* If the next instruction is a jump, move to its target. */
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static void
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i386_follow_jump (void)
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{
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unsigned char buf[4];
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long delta;
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int data16;
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CORE_ADDR pos;
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pos = codestream_tell ();
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data16 = 0;
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if (codestream_peek () == 0x66)
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{
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codestream_get ();
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data16 = 1;
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}
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switch (codestream_get ())
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{
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case 0xe9:
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/* Relative jump: if data16 == 0, disp32, else disp16. */
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if (data16)
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{
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codestream_read (buf, 2);
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delta = extract_signed_integer (buf, 2);
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/* Include the size of the jmp instruction (including the
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0x66 prefix). */
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pos += delta + 4;
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}
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else
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{
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codestream_read (buf, 4);
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delta = extract_signed_integer (buf, 4);
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pos += delta + 5;
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}
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break;
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case 0xeb:
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/* Relative jump, disp8 (ignore data16). */
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codestream_read (buf, 1);
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/* Sign-extend it. */
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delta = extract_signed_integer (buf, 1);
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pos += delta + 2;
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break;
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}
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codestream_seek (pos);
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}
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/* Find & return the amount a local space allocated, and advance the
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codestream to the first register push (if any).
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If the entry sequence doesn't make sense, return -1, and leave
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codestream pointer at a random spot. */
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static long
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i386_get_frame_setup (CORE_ADDR pc)
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{
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unsigned char op;
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codestream_seek (pc);
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i386_follow_jump ();
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op = codestream_get ();
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if (op == 0x58) /* popl %eax */
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{
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/* This function must start with
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popl %eax 0x58
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xchgl %eax, (%esp) 0x87 0x04 0x24
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or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00
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(the System V compiler puts out the second `xchg'
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instruction, and the assembler doesn't try to optimize it, so
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the 'sib' form gets generated). This sequence is used to get
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the address of the return buffer for a function that returns
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a structure. */
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int pos;
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unsigned char buf[4];
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static unsigned char proto1[3] = { 0x87, 0x04, 0x24 };
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static unsigned char proto2[4] = { 0x87, 0x44, 0x24, 0x00 };
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pos = codestream_tell ();
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codestream_read (buf, 4);
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if (memcmp (buf, proto1, 3) == 0)
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pos += 3;
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else if (memcmp (buf, proto2, 4) == 0)
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pos += 4;
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codestream_seek (pos);
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op = codestream_get (); /* Update next opcode. */
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}
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if (op == 0x68 || op == 0x6a)
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{
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/* This function may start with
|
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pushl constant
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call _probe
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addl $4, %esp
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followed by
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pushl %ebp
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etc. */
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int pos;
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unsigned char buf[8];
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/* Skip past the `pushl' instruction; it has either a one-byte
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or a four-byte operand, depending on the opcode. */
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pos = codestream_tell ();
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if (op == 0x68)
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pos += 4;
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else
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pos += 1;
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codestream_seek (pos);
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|
||
/* Read the following 8 bytes, which should be "call _probe" (6
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bytes) followed by "addl $4,%esp" (2 bytes). */
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codestream_read (buf, sizeof (buf));
|
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if (buf[0] == 0xe8 && buf[6] == 0xc4 && buf[7] == 0x4)
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pos += sizeof (buf);
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codestream_seek (pos);
|
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op = codestream_get (); /* Update next opcode. */
|
||
}
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|
||
if (op == 0x55) /* pushl %ebp */
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{
|
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/* Check for "movl %esp, %ebp" -- can be written in two ways. */
|
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switch (codestream_get ())
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{
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case 0x8b:
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if (codestream_get () != 0xec)
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return -1;
|
||
break;
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||
case 0x89:
|
||
if (codestream_get () != 0xe5)
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return -1;
|
||
break;
|
||
default:
|
||
return -1;
|
||
}
|
||
/* Check for stack adjustment
|
||
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subl $XXX, %esp
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||
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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 ();
|
||
if (op == 0x83)
|
||
{
|
||
/* `subl' with 8 bit immediate. */
|
||
codestream_get ();
|
||
if (codestream_get () != 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 ());
|
||
}
|
||
else if (op == 0x81)
|
||
{
|
||
char buf[4];
|
||
/* Maybe it is `subl' with a 32 bit immedediate. */
|
||
codestream_get ();
|
||
if (codestream_get () != 0xec)
|
||
/* Some instruction starting with 0x81 other than `subl'. */
|
||
{
|
||
codestream_seek (codestream_tell () - 2);
|
||
return 0;
|
||
}
|
||
/* It is `subl' with a 32 bit immediate. */
|
||
codestream_read ((unsigned char *) buf, 4);
|
||
return extract_signed_integer (buf, 4);
|
||
}
|
||
else
|
||
{
|
||
return 0;
|
||
}
|
||
}
|
||
else if (op == 0xc8)
|
||
{
|
||
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);
|
||
}
|
||
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_pc_function_start (get_frame_pc (frame))));
|
||
}
|
||
|
||
/* 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. */
|
||
|
||
static CORE_ADDR
|
||
i386_frame_chain (struct frame_info *frame)
|
||
{
|
||
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. */
|
||
|
||
static CORE_ADDR
|
||
i386_frame_saved_pc (struct frame_info *frame)
|
||
{
|
||
if (pc_in_dummy_frame (get_frame_pc (frame)))
|
||
{
|
||
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);
|
||
|
||
if (i386_frameless_signal_p (frame))
|
||
{
|
||
CORE_ADDR sp = i386_sigtramp_saved_sp (get_next_frame (frame));
|
||
return read_memory_unsigned_integer (sp, 4);
|
||
}
|
||
|
||
return read_memory_unsigned_integer (get_frame_base (frame) + 4, 4);
|
||
}
|
||
|
||
/* 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);
|
||
}
|
||
|
||
/* Return number of args passed to a frame.
|
||
Can return -1, meaning no way to tell. */
|
||
|
||
static int
|
||
i386_frame_num_args (struct frame_info *fi)
|
||
{
|
||
#if 1
|
||
return -1;
|
||
#else
|
||
/* This loses because not only might the compiler not be popping the
|
||
args right after the function call, it might be popping args from
|
||
both this call and a previous one, and we would say there are
|
||
more args than there really are. */
|
||
|
||
int retpc;
|
||
unsigned char op;
|
||
struct frame_info *pfi;
|
||
|
||
/* On the i386, the instruction following the call could be:
|
||
popl %ecx - one arg
|
||
addl $imm, %esp - imm/4 args; imm may be 8 or 32 bits
|
||
anything else - zero args. */
|
||
|
||
int frameless;
|
||
|
||
frameless = FRAMELESS_FUNCTION_INVOCATION (fi);
|
||
if (frameless)
|
||
/* In the absence of a frame pointer, GDB doesn't get correct
|
||
values for nameless arguments. Return -1, so it doesn't print
|
||
any nameless arguments. */
|
||
return -1;
|
||
|
||
pfi = get_prev_frame (fi);
|
||
if (pfi == 0)
|
||
{
|
||
/* NOTE: This can happen if we are looking at the frame for
|
||
main, because DEPRECATED_FRAME_CHAIN_VALID won't let us go
|
||
into start. If we have debugging symbols, that's not really
|
||
a big deal; it just means it will only show as many arguments
|
||
to main as are declared. */
|
||
return -1;
|
||
}
|
||
else
|
||
{
|
||
retpc = pfi->pc;
|
||
op = read_memory_integer (retpc, 1);
|
||
if (op == 0x59) /* pop %ecx */
|
||
return 1;
|
||
else if (op == 0x83)
|
||
{
|
||
op = read_memory_integer (retpc + 1, 1);
|
||
if (op == 0xc4)
|
||
/* addl $<signed imm 8 bits>, %esp */
|
||
return (read_memory_integer (retpc + 2, 1) & 0xff) / 4;
|
||
else
|
||
return 0;
|
||
}
|
||
else if (op == 0x81) /* `add' with 32 bit immediate. */
|
||
{
|
||
op = read_memory_integer (retpc + 1, 1);
|
||
if (op == 0xc4)
|
||
/* addl $<imm 32>, %esp */
|
||
return read_memory_integer (retpc + 2, 4) / 4;
|
||
else
|
||
return 0;
|
||
}
|
||
else
|
||
{
|
||
return 0;
|
||
}
|
||
}
|
||
#endif
|
||
}
|
||
|
||
/* 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
|
||
function can start with a branch to startup code at the end.
|
||
|
||
%ebp can be set up with either the 'enter' instruction, or "pushl
|
||
%ebp, movl %esp, %ebp" (`enter' is too slow to be useful, but was
|
||
once used in the System V compiler).
|
||
|
||
Local space is allocated just below the saved %ebp by either the
|
||
'enter' instruction, or by "subl $<size>, %esp". 'enter' has a 16
|
||
bit unsigned argument for space to allocate, and the 'addl'
|
||
instruction could have either a signed byte, or 32 bit immediate.
|
||
|
||
Next, the registers used by this function are pushed. With the
|
||
System V compiler they will always be in the order: %edi, %esi,
|
||
%ebx (and sometimes a harmless bug causes it to also save but not
|
||
restore %eax); however, the code below is willing to see the pushes
|
||
in any order, and will handle up to 8 of them.
|
||
|
||
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)
|
||
{
|
||
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_pc_function_start (get_frame_pc (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)[FP_REGNUM] = get_frame_base (fip);
|
||
}
|
||
|
||
/* Return PC of first real instruction. */
|
||
|
||
static CORE_ADDR
|
||
i386_skip_prologue (CORE_ADDR pc)
|
||
{
|
||
unsigned char op;
|
||
int i;
|
||
static unsigned char pic_pat[6] =
|
||
{ 0xe8, 0, 0, 0, 0, /* call 0x0 */
|
||
0x5b, /* popl %ebx */
|
||
};
|
||
CORE_ADDR pos;
|
||
|
||
if (i386_get_frame_setup (pc) < 0)
|
||
return (pc);
|
||
|
||
/* Found valid frame setup -- codestream now points to start of push
|
||
instructions for saving registers. */
|
||
|
||
/* 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 ();
|
||
}
|
||
|
||
/* 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
|
||
|
||
call 0x0
|
||
popl %ebx
|
||
movl %ebx,x(%ebp) (optional)
|
||
addl y,%ebx
|
||
|
||
This code is with the rest of the prologue (at the end of the
|
||
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 ();
|
||
if (pic_pat[i] != op)
|
||
break;
|
||
}
|
||
if (i == 6)
|
||
{
|
||
unsigned char buf[4];
|
||
long delta = 6;
|
||
|
||
op = codestream_get ();
|
||
if (op == 0x89) /* movl %ebx, x(%ebp) */
|
||
{
|
||
op = codestream_get ();
|
||
if (op == 0x5d) /* One byte offset from %ebp. */
|
||
{
|
||
delta += 3;
|
||
codestream_read (buf, 1);
|
||
}
|
||
else if (op == 0x9d) /* Four byte offset from %ebp. */
|
||
{
|
||
delta += 6;
|
||
codestream_read (buf, 4);
|
||
}
|
||
else /* Unexpected instruction. */
|
||
delta = -1;
|
||
op = codestream_get ();
|
||
}
|
||
/* addl y,%ebx */
|
||
if (delta > 0 && op == 0x81 && codestream_get () == 0xc3)
|
||
{
|
||
pos += delta + 6;
|
||
}
|
||
}
|
||
codestream_seek (pos);
|
||
|
||
i386_follow_jump ();
|
||
|
||
return (codestream_tell ());
|
||
}
|
||
|
||
/* 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.
|
||
|
||
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 unsigned char break_insn[] = { 0xcc }; /* int 3 */
|
||
|
||
*len = sizeof (break_insn);
|
||
return break_insn;
|
||
}
|
||
|
||
/* Push the return address (pointing to the call dummy) onto the stack
|
||
and return the new value for the stack pointer. */
|
||
|
||
static CORE_ADDR
|
||
i386_push_return_address (CORE_ADDR pc, CORE_ADDR sp)
|
||
{
|
||
char buf[4];
|
||
|
||
store_unsigned_integer (buf, 4, CALL_DUMMY_ADDRESS ());
|
||
write_memory (sp - 4, buf, 4);
|
||
return sp - 4;
|
||
}
|
||
|
||
static void
|
||
i386_do_pop_frame (struct frame_info *frame)
|
||
{
|
||
CORE_ADDR fp;
|
||
int regnum;
|
||
char regbuf[I386_MAX_REGISTER_SIZE];
|
||
|
||
fp = get_frame_base (frame);
|
||
i386_frame_init_saved_regs (frame);
|
||
|
||
for (regnum = 0; regnum < NUM_REGS; regnum++)
|
||
{
|
||
CORE_ADDR addr;
|
||
addr = get_frame_saved_regs (frame)[regnum];
|
||
if (addr)
|
||
{
|
||
read_memory (addr, regbuf, REGISTER_RAW_SIZE (regnum));
|
||
deprecated_write_register_gen (regnum, regbuf);
|
||
}
|
||
}
|
||
write_register (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 ();
|
||
}
|
||
|
||
static void
|
||
i386_pop_frame (void)
|
||
{
|
||
generic_pop_current_frame (i386_do_pop_frame);
|
||
}
|
||
|
||
|
||
/* Figure out where the longjmp will land. Slurp the args out of the
|
||
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. */
|
||
|
||
static int
|
||
i386_get_longjmp_target (CORE_ADDR *pc)
|
||
{
|
||
char buf[8];
|
||
CORE_ADDR sp, jb_addr;
|
||
int jb_pc_offset = gdbarch_tdep (current_gdbarch)->jb_pc_offset;
|
||
int len = TARGET_PTR_BIT / TARGET_CHAR_BIT;
|
||
|
||
/* If JB_PC_OFFSET is -1, we have no way to find out where the
|
||
longjmp will land. */
|
||
if (jb_pc_offset == -1)
|
||
return 0;
|
||
|
||
sp = read_register (SP_REGNUM);
|
||
if (target_read_memory (sp + len, buf, len))
|
||
return 0;
|
||
|
||
jb_addr = extract_address (buf, len);
|
||
if (target_read_memory (jb_addr + jb_pc_offset, buf, len))
|
||
return 0;
|
||
|
||
*pc = extract_address (buf, len);
|
||
return 1;
|
||
}
|
||
|
||
|
||
static CORE_ADDR
|
||
i386_push_arguments (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];
|
||
|
||
sp -= 4;
|
||
store_address (buf, 4, struct_addr);
|
||
write_memory (sp, buf, 4);
|
||
}
|
||
|
||
return sp;
|
||
}
|
||
|
||
/* 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 */
|
||
|
||
/* Extract from an array REGBUF containing the (raw) register state, a
|
||
function return value of TYPE, and copy that, in virtual format,
|
||
into VALBUF. */
|
||
|
||
static void
|
||
i386_extract_return_value (struct type *type, struct regcache *regcache,
|
||
void *dst)
|
||
{
|
||
bfd_byte *valbuf = dst;
|
||
int len = TYPE_LENGTH (type);
|
||
char buf[I386_MAX_REGISTER_SIZE];
|
||
|
||
if (TYPE_CODE (type) == TYPE_CODE_STRUCT
|
||
&& TYPE_NFIELDS (type) == 1)
|
||
{
|
||
i386_extract_return_value (TYPE_FIELD_TYPE (type, 0), regcache, valbuf);
|
||
return;
|
||
}
|
||
|
||
if (TYPE_CODE (type) == TYPE_CODE_FLT)
|
||
{
|
||
if (FP0_REGNUM == 0)
|
||
{
|
||
warning ("Cannot find floating-point return value.");
|
||
memset (valbuf, 0, len);
|
||
return;
|
||
}
|
||
|
||
/* Floating-point return values can be found in %st(0). Convert
|
||
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);
|
||
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);
|
||
|
||
if (len <= low_size)
|
||
{
|
||
regcache_raw_read (regcache, LOW_RETURN_REGNUM, buf);
|
||
memcpy (valbuf, buf, len);
|
||
}
|
||
else if (len <= (low_size + high_size))
|
||
{
|
||
regcache_raw_read (regcache, LOW_RETURN_REGNUM, buf);
|
||
memcpy (valbuf, buf, low_size);
|
||
regcache_raw_read (regcache, HIGH_RETURN_REGNUM, buf);
|
||
memcpy (valbuf + low_size, buf, len - low_size);
|
||
}
|
||
else
|
||
internal_error (__FILE__, __LINE__,
|
||
"Cannot extract return value of %d bytes long.", len);
|
||
}
|
||
}
|
||
|
||
/* Write into the appropriate registers a function return value stored
|
||
in VALBUF of type TYPE, given in virtual format. */
|
||
|
||
static void
|
||
i386_store_return_value (struct type *type, struct regcache *regcache,
|
||
const void *valbuf)
|
||
{
|
||
int len = TYPE_LENGTH (type);
|
||
|
||
if (TYPE_CODE (type) == TYPE_CODE_STRUCT
|
||
&& TYPE_NFIELDS (type) == 1)
|
||
{
|
||
i386_store_return_value (TYPE_FIELD_TYPE (type, 0), regcache, valbuf);
|
||
return;
|
||
}
|
||
|
||
if (TYPE_CODE (type) == TYPE_CODE_FLT)
|
||
{
|
||
ULONGEST fstat;
|
||
char buf[FPU_REG_RAW_SIZE];
|
||
|
||
if (FP0_REGNUM == 0)
|
||
{
|
||
warning ("Cannot set floating-point return value.");
|
||
return;
|
||
}
|
||
|
||
/* Returning floating-point values is a bit tricky. Apart from
|
||
storing the return value in %st(0), we have to simulate the
|
||
state of the FPU at function return point. */
|
||
|
||
/* Convert the value found in VALBUF to the extended
|
||
floating-point format used by the FPU. This is probably
|
||
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);
|
||
|
||
/* Set the top of the floating-point register stack to 7. The
|
||
actual value doesn't really matter, but 7 is what a normal
|
||
function return would end up with if the program started out
|
||
with a freshly initialized FPU. */
|
||
regcache_raw_read_unsigned (regcache, FSTAT_REGNUM, &fstat);
|
||
fstat |= (7 << 11);
|
||
regcache_raw_write_unsigned (regcache, FSTAT_REGNUM, fstat);
|
||
|
||
/* Mark %st(1) through %st(7) as empty. Since we set the top of
|
||
the floating-point register stack to 7, the appropriate value
|
||
for the tag word is 0x3fff. */
|
||
regcache_raw_write_unsigned (regcache, FTAG_REGNUM, 0x3fff);
|
||
}
|
||
else
|
||
{
|
||
int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM);
|
||
int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM);
|
||
|
||
if (len <= low_size)
|
||
regcache_raw_write_part (regcache, LOW_RETURN_REGNUM, 0, len, valbuf);
|
||
else if (len <= (low_size + high_size))
|
||
{
|
||
regcache_raw_write (regcache, LOW_RETURN_REGNUM, valbuf);
|
||
regcache_raw_write_part (regcache, HIGH_RETURN_REGNUM, 0,
|
||
len - low_size, (char *) valbuf + low_size);
|
||
}
|
||
else
|
||
internal_error (__FILE__, __LINE__,
|
||
"Cannot store return value of %d bytes long.", len);
|
||
}
|
||
}
|
||
|
||
/* Extract from REGCACHE, which contains the (raw) register state, the
|
||
address in which a function should return its structure value, as a
|
||
CORE_ADDR. */
|
||
|
||
static CORE_ADDR
|
||
i386_extract_struct_value_address (struct regcache *regcache)
|
||
{
|
||
ULONGEST addr;
|
||
|
||
regcache_raw_read_unsigned (regcache, LOW_RETURN_REGNUM, &addr);
|
||
return addr;
|
||
}
|
||
|
||
|
||
/* This is the variable that is set with "set struct-convention", and
|
||
its legitimate values. */
|
||
static const char default_struct_convention[] = "default";
|
||
static const char pcc_struct_convention[] = "pcc";
|
||
static const char reg_struct_convention[] = "reg";
|
||
static const char *valid_conventions[] =
|
||
{
|
||
default_struct_convention,
|
||
pcc_struct_convention,
|
||
reg_struct_convention,
|
||
NULL
|
||
};
|
||
static const char *struct_convention = default_struct_convention;
|
||
|
||
static int
|
||
i386_use_struct_convention (int gcc_p, struct type *type)
|
||
{
|
||
enum struct_return struct_return;
|
||
|
||
if (struct_convention == default_struct_convention)
|
||
struct_return = gdbarch_tdep (current_gdbarch)->struct_return;
|
||
else if (struct_convention == pcc_struct_convention)
|
||
struct_return = pcc_struct_return;
|
||
else
|
||
struct_return = reg_struct_return;
|
||
|
||
return generic_use_struct_convention (struct_return == reg_struct_return,
|
||
type);
|
||
}
|
||
|
||
|
||
/* Return the GDB type object for the "standard" data type of data in
|
||
register REGNUM. Perhaps %esi and %edi should go here, but
|
||
potentially they could be used for things other than address. */
|
||
|
||
static struct type *
|
||
i386_register_type (struct gdbarch *gdbarch, int regnum)
|
||
{
|
||
if (regnum == PC_REGNUM || regnum == FP_REGNUM || regnum == SP_REGNUM)
|
||
return lookup_pointer_type (builtin_type_void);
|
||
|
||
if (i386_fp_regnum_p (regnum))
|
||
return builtin_type_i387_ext;
|
||
|
||
if (i386_sse_regnum_p (regnum))
|
||
return builtin_type_vec128i;
|
||
|
||
if (i386_mmx_regnum_p (regnum))
|
||
return builtin_type_vec64i;
|
||
|
||
return builtin_type_int;
|
||
}
|
||
|
||
/* Map a cooked register onto a raw register or memory. For the i386,
|
||
the MMX registers need to be mapped onto floating point registers. */
|
||
|
||
static int
|
||
mmx_regnum_to_fp_regnum (struct regcache *regcache, int regnum)
|
||
{
|
||
int mmxi;
|
||
ULONGEST fstat;
|
||
int tos;
|
||
int fpi;
|
||
mmxi = regnum - MM0_REGNUM;
|
||
regcache_raw_read_unsigned (regcache, FSTAT_REGNUM, &fstat);
|
||
tos = (fstat >> 11) & 0x7;
|
||
fpi = (mmxi + tos) % 8;
|
||
return (FP0_REGNUM + fpi);
|
||
}
|
||
|
||
static void
|
||
i386_pseudo_register_read (struct gdbarch *gdbarch, struct regcache *regcache,
|
||
int regnum, void *buf)
|
||
{
|
||
if (i386_mmx_regnum_p (regnum))
|
||
{
|
||
char *mmx_buf = alloca (MAX_REGISTER_RAW_SIZE);
|
||
int fpnum = mmx_regnum_to_fp_regnum (regcache, regnum);
|
||
regcache_raw_read (regcache, fpnum, mmx_buf);
|
||
/* Extract (always little endian). */
|
||
memcpy (buf, mmx_buf, REGISTER_RAW_SIZE (regnum));
|
||
}
|
||
else
|
||
regcache_raw_read (regcache, regnum, buf);
|
||
}
|
||
|
||
static void
|
||
i386_pseudo_register_write (struct gdbarch *gdbarch, struct regcache *regcache,
|
||
int regnum, const void *buf)
|
||
{
|
||
if (i386_mmx_regnum_p (regnum))
|
||
{
|
||
char *mmx_buf = alloca (MAX_REGISTER_RAW_SIZE);
|
||
int fpnum = 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));
|
||
/* ... Write. */
|
||
regcache_raw_write (regcache, fpnum, mmx_buf);
|
||
}
|
||
else
|
||
regcache_raw_write (regcache, regnum, buf);
|
||
}
|
||
|
||
/* 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. */
|
||
|
||
static int
|
||
i386_register_convertible (int regnum)
|
||
{
|
||
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. */
|
||
|
||
static void
|
||
i386_register_convert_to_virtual (int regnum, struct type *type,
|
||
char *from, char *to)
|
||
{
|
||
gdb_assert (i386_fp_regnum_p (regnum));
|
||
|
||
/* We only support floating-point values. */
|
||
if (TYPE_CODE (type) != TYPE_CODE_FLT)
|
||
{
|
||
warning ("Cannot convert floating-point register value "
|
||
"to non-floating-point type.");
|
||
memset (to, 0, TYPE_LENGTH (type));
|
||
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);
|
||
}
|
||
|
||
/* Convert data from virtual format with type TYPE in buffer FROM to
|
||
raw format for register REGNUM in buffer TO. */
|
||
|
||
static void
|
||
i386_register_convert_to_raw (struct type *type, int regnum,
|
||
char *from, char *to)
|
||
{
|
||
gdb_assert (i386_fp_regnum_p (regnum));
|
||
|
||
/* We only support floating-point values. */
|
||
if (TYPE_CODE (type) != TYPE_CODE_FLT)
|
||
{
|
||
warning ("Cannot convert non-floating-point type "
|
||
"to floating-point register value.");
|
||
memset (to, 0, TYPE_LENGTH (type));
|
||
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);
|
||
}
|
||
|
||
|
||
#ifdef STATIC_TRANSFORM_NAME
|
||
/* SunPRO encodes the static variables. This is not related to C++
|
||
mangling, it is done for C too. */
|
||
|
||
char *
|
||
sunpro_static_transform_name (char *name)
|
||
{
|
||
char *p;
|
||
if (IS_STATIC_TRANSFORM_NAME (name))
|
||
{
|
||
/* For file-local statics there will be a period, a bunch of
|
||
junk (the contents of which match a string given in the
|
||
N_OPT), a period and the name. For function-local statics
|
||
there will be a bunch of junk (which seems to change the
|
||
second character from 'A' to 'B'), a period, the name of the
|
||
function, and the name. So just skip everything before the
|
||
last period. */
|
||
p = strrchr (name, '.');
|
||
if (p != NULL)
|
||
name = p + 1;
|
||
}
|
||
return name;
|
||
}
|
||
#endif /* STATIC_TRANSFORM_NAME */
|
||
|
||
|
||
/* Stuff for WIN32 PE style DLL's but is pretty generic really. */
|
||
|
||
CORE_ADDR
|
||
i386_pe_skip_trampoline_code (CORE_ADDR pc, char *name)
|
||
{
|
||
if (pc && read_memory_unsigned_integer (pc, 2) == 0x25ff) /* jmp *(dest) */
|
||
{
|
||
unsigned long indirect = read_memory_unsigned_integer (pc + 2, 4);
|
||
struct minimal_symbol *indsym =
|
||
indirect ? lookup_minimal_symbol_by_pc (indirect) : 0;
|
||
char *symname = indsym ? SYMBOL_LINKAGE_NAME (indsym) : 0;
|
||
|
||
if (symname)
|
||
{
|
||
if (strncmp (symname, "__imp_", 6) == 0
|
||
|| strncmp (symname, "_imp_", 5) == 0)
|
||
return name ? 1 : read_memory_unsigned_integer (indirect, 4);
|
||
}
|
||
}
|
||
return 0; /* Not a trampoline. */
|
||
}
|
||
|
||
|
||
/* Return non-zero if PC and NAME show that we are in a signal
|
||
trampoline. */
|
||
|
||
static int
|
||
i386_pc_in_sigtramp (CORE_ADDR pc, char *name)
|
||
{
|
||
return (name && strcmp ("_sigtramp", name) == 0);
|
||
}
|
||
|
||
|
||
/* We have two flavours of disassembly. The machinery on this page
|
||
deals with switching between those. */
|
||
|
||
static int
|
||
i386_print_insn (bfd_vma pc, disassemble_info *info)
|
||
{
|
||
gdb_assert (disassembly_flavor == att_flavor
|
||
|| disassembly_flavor == intel_flavor);
|
||
|
||
/* FIXME: kettenis/20020915: Until disassembler_options is properly
|
||
constified, cast to prevent a compiler warning. */
|
||
info->disassembler_options = (char *) disassembly_flavor;
|
||
info->mach = gdbarch_bfd_arch_info (current_gdbarch)->mach;
|
||
|
||
return print_insn_i386 (pc, info);
|
||
}
|
||
|
||
|
||
/* There are a few i386 architecture variants that differ only
|
||
slightly from the generic i386 target. For now, we don't give them
|
||
their own source file, but include them here. As a consequence,
|
||
they'll always be included. */
|
||
|
||
/* System V Release 4 (SVR4). */
|
||
|
||
static int
|
||
i386_svr4_pc_in_sigtramp (CORE_ADDR pc, char *name)
|
||
{
|
||
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. */
|
||
|
||
static CORE_ADDR
|
||
i386_svr4_sigcontext_addr (struct frame_info *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;
|
||
}
|
||
|
||
gdb_assert (sigcontext_offset != -1);
|
||
|
||
if (get_next_frame (frame))
|
||
return get_frame_base (get_next_frame (frame)) + sigcontext_offset;
|
||
return read_register (SP_REGNUM) + sigcontext_offset;
|
||
}
|
||
|
||
|
||
/* DJGPP. */
|
||
|
||
static int
|
||
i386_go32_pc_in_sigtramp (CORE_ADDR pc, char *name)
|
||
{
|
||
/* DJGPP doesn't have any special frames for signal handlers. */
|
||
return 0;
|
||
}
|
||
|
||
|
||
/* Generic ELF. */
|
||
|
||
void
|
||
i386_elf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
/* We typically use stabs-in-ELF with the DWARF register numbering. */
|
||
set_gdbarch_stab_reg_to_regnum (gdbarch, i386_dwarf_reg_to_regnum);
|
||
}
|
||
|
||
/* System V Release 4 (SVR4). */
|
||
|
||
void
|
||
i386_svr4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
/* System V Release 4 uses ELF. */
|
||
i386_elf_init_abi (info, gdbarch);
|
||
|
||
/* System V Release 4 has shared libraries. */
|
||
set_gdbarch_in_solib_call_trampoline (gdbarch, in_plt_section);
|
||
set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
|
||
|
||
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->jb_pc_offset = 20;
|
||
}
|
||
|
||
/* DJGPP. */
|
||
|
||
static void
|
||
i386_go32_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
set_gdbarch_pc_in_sigtramp (gdbarch, i386_go32_pc_in_sigtramp);
|
||
|
||
tdep->jb_pc_offset = 36;
|
||
}
|
||
|
||
/* NetWare. */
|
||
|
||
static void
|
||
i386_nw_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
tdep->jb_pc_offset = 24;
|
||
}
|
||
|
||
|
||
/* i386 register groups. In addition to the normal groups, add "mmx"
|
||
and "sse". */
|
||
|
||
static struct reggroup *i386_sse_reggroup;
|
||
static struct reggroup *i386_mmx_reggroup;
|
||
|
||
static void
|
||
i386_init_reggroups (void)
|
||
{
|
||
i386_sse_reggroup = reggroup_new ("sse", USER_REGGROUP);
|
||
i386_mmx_reggroup = reggroup_new ("mmx", USER_REGGROUP);
|
||
}
|
||
|
||
static void
|
||
i386_add_reggroups (struct gdbarch *gdbarch)
|
||
{
|
||
reggroup_add (gdbarch, i386_sse_reggroup);
|
||
reggroup_add (gdbarch, i386_mmx_reggroup);
|
||
reggroup_add (gdbarch, general_reggroup);
|
||
reggroup_add (gdbarch, float_reggroup);
|
||
reggroup_add (gdbarch, all_reggroup);
|
||
reggroup_add (gdbarch, save_reggroup);
|
||
reggroup_add (gdbarch, restore_reggroup);
|
||
reggroup_add (gdbarch, vector_reggroup);
|
||
reggroup_add (gdbarch, system_reggroup);
|
||
}
|
||
|
||
int
|
||
i386_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
|
||
struct reggroup *group)
|
||
{
|
||
int sse_regnum_p = (i386_sse_regnum_p (regnum)
|
||
|| i386_mxcsr_regnum_p (regnum));
|
||
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 sse_regnum_p;
|
||
if (group == vector_reggroup)
|
||
return (mmx_regnum_p || sse_regnum_p);
|
||
if (group == float_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);
|
||
}
|
||
|
||
|
||
static struct gdbarch *
|
||
i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
|
||
{
|
||
struct gdbarch_tdep *tdep;
|
||
struct gdbarch *gdbarch;
|
||
|
||
/* If there is already a candidate, use it. */
|
||
arches = gdbarch_list_lookup_by_info (arches, &info);
|
||
if (arches != NULL)
|
||
return arches->gdbarch;
|
||
|
||
/* Allocate space for the new architecture. */
|
||
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 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->jb_pc_offset = -1;
|
||
tdep->struct_return = pcc_struct_return;
|
||
tdep->sigtramp_start = 0;
|
||
tdep->sigtramp_end = 0;
|
||
tdep->sigcontext_addr = NULL;
|
||
tdep->sc_pc_offset = -1;
|
||
tdep->sc_sp_offset = -1;
|
||
|
||
/* The format used for `long double' on almost all i386 targets is
|
||
the i387 extended floating-point format. In fact, of all targets
|
||
in the GCC 2.95 tree, only OSF/1 does it different, and insists
|
||
on having a `long double' that's not `long' at all. */
|
||
set_gdbarch_long_double_format (gdbarch, &floatformat_i387_ext);
|
||
|
||
/* Although the i387 extended floating-point has only 80 significant
|
||
bits, a `long double' actually takes up 96, probably to enforce
|
||
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);
|
||
|
||
set_gdbarch_sp_regnum (gdbarch, 4); /* %esp */
|
||
set_gdbarch_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) */
|
||
|
||
/* Use the "default" register numbering scheme for stabs and COFF. */
|
||
set_gdbarch_stab_reg_to_regnum (gdbarch, i386_stab_reg_to_regnum);
|
||
set_gdbarch_sdb_reg_to_regnum (gdbarch, i386_stab_reg_to_regnum);
|
||
|
||
/* Use the DWARF register numbering scheme for DWARF and DWARF 2. */
|
||
set_gdbarch_dwarf_reg_to_regnum (gdbarch, i386_dwarf_reg_to_regnum);
|
||
set_gdbarch_dwarf2_reg_to_regnum (gdbarch, i386_dwarf_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_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_call_dummy_words (gdbarch, NULL);
|
||
set_gdbarch_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);
|
||
|
||
/* "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_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_inner_than (gdbarch, core_addr_lessthan);
|
||
|
||
set_gdbarch_breakpoint_from_pc (gdbarch, i386_breakpoint_from_pc);
|
||
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_saved_pc_after_call (gdbarch, i386_saved_pc_after_call);
|
||
set_gdbarch_frame_num_args (gdbarch, i386_frame_num_args);
|
||
set_gdbarch_pc_in_sigtramp (gdbarch, i386_pc_in_sigtramp);
|
||
|
||
/* Wire in the MMX registers. */
|
||
set_gdbarch_num_pseudo_regs (gdbarch, mmx_num_regs);
|
||
set_gdbarch_pseudo_register_read (gdbarch, i386_pseudo_register_read);
|
||
set_gdbarch_pseudo_register_write (gdbarch, i386_pseudo_register_write);
|
||
|
||
set_gdbarch_print_insn (gdbarch, i386_print_insn);
|
||
|
||
/* 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);
|
||
|
||
/* Hook in ABI-specific overrides, if they have been registered. */
|
||
gdbarch_init_osabi (info, gdbarch);
|
||
|
||
return gdbarch;
|
||
}
|
||
|
||
static enum gdb_osabi
|
||
i386_coff_osabi_sniffer (bfd *abfd)
|
||
{
|
||
if (strcmp (bfd_get_target (abfd), "coff-go32-exe") == 0
|
||
|| strcmp (bfd_get_target (abfd), "coff-go32") == 0)
|
||
return GDB_OSABI_GO32;
|
||
|
||
return GDB_OSABI_UNKNOWN;
|
||
}
|
||
|
||
static enum gdb_osabi
|
||
i386_nlm_osabi_sniffer (bfd *abfd)
|
||
{
|
||
return GDB_OSABI_NETWARE;
|
||
}
|
||
|
||
|
||
/* Provide a prototype to silence -Wmissing-prototypes. */
|
||
void _initialize_i386_tdep (void);
|
||
|
||
void
|
||
_initialize_i386_tdep (void)
|
||
{
|
||
register_gdbarch_init (bfd_arch_i386, i386_gdbarch_init);
|
||
|
||
/* Add the variable that controls the disassembly flavor. */
|
||
{
|
||
struct cmd_list_element *new_cmd;
|
||
|
||
new_cmd = add_set_enum_cmd ("disassembly-flavor", no_class,
|
||
valid_flavors,
|
||
&disassembly_flavor,
|
||
"\
|
||
Set the disassembly flavor, the valid values are \"att\" and \"intel\", \
|
||
and the default value is \"att\".",
|
||
&setlist);
|
||
add_show_from_set (new_cmd, &showlist);
|
||
}
|
||
|
||
/* Add the variable that controls the convention for returning
|
||
structs. */
|
||
{
|
||
struct cmd_list_element *new_cmd;
|
||
|
||
new_cmd = add_set_enum_cmd ("struct-convention", no_class,
|
||
valid_conventions,
|
||
&struct_convention, "\
|
||
Set the convention for returning small structs, valid values \
|
||
are \"default\", \"pcc\" and \"reg\", and the default value is \"default\".",
|
||
&setlist);
|
||
add_show_from_set (new_cmd, &showlist);
|
||
}
|
||
|
||
gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_coff_flavour,
|
||
i386_coff_osabi_sniffer);
|
||
gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_nlm_flavour,
|
||
i386_nlm_osabi_sniffer);
|
||
|
||
gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_SVR4,
|
||
i386_svr4_init_abi);
|
||
gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_GO32,
|
||
i386_go32_init_abi);
|
||
gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_NETWARE,
|
||
i386_nw_init_abi);
|
||
|
||
/* Initialize the i386 specific register groups. */
|
||
i386_init_reggroups ();
|
||
}
|