972 lines
26 KiB
C
972 lines
26 KiB
C
/* Intel 386 target-dependent stuff.
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Copyright (C) 1988, 1989, 1991, 1994, 1995, 1996, 1998
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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 "target.h"
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#include "floatformat.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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static long i386_get_frame_setup PARAMS ((CORE_ADDR));
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static void i386_follow_jump PARAMS ((void));
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static void codestream_read PARAMS ((unsigned char *, int));
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static void codestream_seek PARAMS ((CORE_ADDR));
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static unsigned char codestream_fill PARAMS ((int));
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CORE_ADDR skip_trampoline_code PARAMS ((CORE_ADDR, char *));
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static int gdb_print_insn_i386 (bfd_vma, disassemble_info *);
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void _initialize_i386_tdep PARAMS ((void));
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/* This is the variable the is set with "set disassembly-flavor",
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and its legitimate values. */
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static char att_flavor[] = "att";
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static char intel_flavor[] = "intel";
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static 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 char *disassembly_flavor = att_flavor;
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/* This is used to keep the bfd arch_info in sync with the disassembly flavor. */
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static void set_disassembly_flavor_sfunc PARAMS ((char *, int, struct cmd_list_element *));
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static void set_disassembly_flavor ();
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/* Stdio style buffering was used to minimize calls to ptrace, but this
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buffering did not take into account that the code section being accessed
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may not be an even number of buffers long (even if the buffer is only
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sizeof(int) long). In cases where the code section size happened to
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be a non-integral number of buffers long, attempting to read the last
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buffer would fail. Simply using target_read_memory and ignoring errors,
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rather than read_memory, is not the correct solution, since legitimate
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access errors would then be totally ignored. To properly handle this
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situation and continue to use buffering would require that this code
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be able to determine the minimum code section size granularity (not the
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alignment of the section itself, since the actual failing case that
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pointed out this problem had a section alignment of 4 but was not a
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multiple of 4 bytes long), on a target by target basis, and then
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adjust it's buffer size accordingly. This is messy, but potentially
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feasible. It probably needs the bfd library's help and support. For
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now, the 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() (codestream_cnt == 0 ? \
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codestream_fill(1): codestream_buf[codestream_off])
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#define codestream_get() (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 (peek_flag)
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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 (place)
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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 (buf, count)
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unsigned char *buf;
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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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/* next instruction is a jump, move to target */
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static void
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i386_follow_jump ()
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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 size of jmp inst (including the 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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/*
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* find & return amound a local space allocated, and advance codestream to
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* first register push (if any)
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*
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* if entry sequence doesn't make sense, return -1, and leave
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* codestream pointer random
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*/
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static long
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i386_get_frame_setup (pc)
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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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/*
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* this function must start with
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*
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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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*
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* (the system 5 compiler puts out the second xchg
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* inst, and the assembler doesn't try to optimize it,
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* so the 'sib' form gets generated)
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*
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* this sequence is used to get the address of the return
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* buffer for a function that returns a structure
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*/
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int pos;
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unsigned char buf[4];
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static unsigned char proto1[3] =
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{0x87, 0x04, 0x24};
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static unsigned char proto2[4] =
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{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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/*
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* this function may start with
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*
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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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*/
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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 bytes)
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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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}
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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 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);
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break;
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case 0x89:
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if (codestream_get () != 0xe5)
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return (-1);
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break;
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default:
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return (-1);
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}
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/* 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
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* from a 32 bit reg, so we don't have to worry
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* about a data16 prefix
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*/
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op = codestream_peek ();
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if (op == 0x83)
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{
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/* subl with 8 bit immed */
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codestream_get ();
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if (codestream_get () != 0xec)
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/* Some instruction starting with 0x83 other than subl. */
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{
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codestream_seek (codestream_tell () - 2);
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return 0;
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}
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/* subl with signed byte immediate
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* (though it wouldn't make sense to be negative)
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*/
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return (codestream_get ());
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}
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else if (op == 0x81)
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{
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char buf[4];
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/* Maybe it is subl with 32 bit immedediate. */
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codestream_get ();
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if (codestream_get () != 0xec)
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/* Some instruction starting with 0x81 other than subl. */
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{
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codestream_seek (codestream_tell () - 2);
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return 0;
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}
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/* It is subl with 32 bit immediate. */
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codestream_read ((unsigned char *) buf, 4);
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return extract_signed_integer (buf, 4);
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}
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else
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{
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return (0);
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}
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}
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else if (op == 0xc8)
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{
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char buf[2];
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/* enter instruction: arg is 16 bit unsigned immed */
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codestream_read ((unsigned char *) buf, 2);
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codestream_get (); /* flush final byte of enter instruction */
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return extract_unsigned_integer (buf, 2);
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}
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return (-1);
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}
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/* Return number of args passed to a frame.
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Can return -1, meaning no way to tell. */
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int
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i386_frame_num_args (fi)
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struct frame_info *fi;
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{
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#if 1
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return -1;
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#else
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/* This loses because not only might the compiler not be popping the
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args right after the function call, it might be popping args from both
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this call and a previous one, and we would say there are more args
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than there really are. */
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int retpc;
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unsigned char op;
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struct frame_info *pfi;
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/* on the 386, the instruction following the call could be:
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popl %ecx - one arg
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addl $imm, %esp - imm/4 args; imm may be 8 or 32 bits
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anything else - zero args */
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int frameless;
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frameless = FRAMELESS_FUNCTION_INVOCATION (fi);
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if (frameless)
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/* In the absence of a frame pointer, GDB doesn't get correct values
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for nameless arguments. Return -1, so it doesn't print any
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nameless arguments. */
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return -1;
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pfi = get_prev_frame (fi);
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if (pfi == 0)
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{
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/* Note: this can happen if we are looking at the frame for
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main, because FRAME_CHAIN_VALID won't let us go into
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start. If we have debugging symbols, that's not really
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a big deal; it just means it will only show as many arguments
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to main as are declared. */
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return -1;
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}
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else
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{
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retpc = pfi->pc;
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op = read_memory_integer (retpc, 1);
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if (op == 0x59)
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/* pop %ecx */
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return 1;
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else if (op == 0x83)
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{
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op = read_memory_integer (retpc + 1, 1);
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if (op == 0xc4)
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/* addl $<signed imm 8 bits>, %esp */
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return (read_memory_integer (retpc + 2, 1) & 0xff) / 4;
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else
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return 0;
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}
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else if (op == 0x81)
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{ /* add with 32 bit immediate */
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op = read_memory_integer (retpc + 1, 1);
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if (op == 0xc4)
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/* addl $<imm 32>, %esp */
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return read_memory_integer (retpc + 2, 4) / 4;
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else
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return 0;
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}
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else
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{
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return 0;
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}
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}
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#endif
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}
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/*
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* parse the first few instructions of the function to see
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* what registers were stored.
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*
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* We handle these cases:
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*
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* The startup sequence can be at the start of the function,
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* or the function can start with a branch to startup code at the end.
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*
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* %ebp can be set up with either the 'enter' instruction, or
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* 'pushl %ebp, movl %esp, %ebp' (enter is too slow to be useful,
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* but was once used in the sys5 compiler)
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*
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* Local space is allocated just below the saved %ebp by either the
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* 'enter' instruction, or by 'subl $<size>, %esp'. 'enter' has
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* a 16 bit unsigned argument for space to allocate, and the
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* 'addl' instruction could have either a signed byte, or
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* 32 bit immediate.
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*
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* Next, the registers used by this function are pushed. In
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* the sys5 compiler they will always be in the order: %edi, %esi, %ebx
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* (and sometimes a harmless bug causes it to also save but not restore %eax);
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* however, the code below is willing to see the pushes in any order,
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* and will handle up to 8 of them.
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*
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* If the setup sequence is at the end of the function, then the
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* next instruction will be a branch back to the start.
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*/
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void
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i386_frame_find_saved_regs (fip, fsrp)
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struct frame_info *fip;
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struct frame_saved_regs *fsrp;
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{
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long locals = -1;
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unsigned char op;
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CORE_ADDR dummy_bottom;
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CORE_ADDR adr;
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CORE_ADDR pc;
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int i;
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memset (fsrp, 0, sizeof *fsrp);
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/* if frame is the end of a dummy, compute where the
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* beginning would be
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*/
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dummy_bottom = fip->frame - 4 - REGISTER_BYTES - CALL_DUMMY_LENGTH;
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/* check if the PC is in the stack, in a dummy frame */
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if (dummy_bottom <= fip->pc && fip->pc <= fip->frame)
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{
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/* all regs were saved by push_call_dummy () */
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adr = fip->frame;
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for (i = 0; i < NUM_REGS; i++)
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{
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adr -= REGISTER_RAW_SIZE (i);
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fsrp->regs[i] = adr;
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}
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return;
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}
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pc = get_pc_function_start (fip->pc);
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if (pc != 0)
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locals = i386_get_frame_setup (pc);
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if (locals >= 0)
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{
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adr = fip->frame - 4 - locals;
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for (i = 0; i < 8; i++)
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{
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op = codestream_get ();
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if (op < 0x50 || op > 0x57)
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break;
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#ifdef I386_REGNO_TO_SYMMETRY
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/* Dynix uses different internal numbering. Ick. */
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fsrp->regs[I386_REGNO_TO_SYMMETRY (op - 0x50)] = adr;
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#else
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fsrp->regs[op - 0x50] = adr;
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#endif
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adr -= 4;
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}
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}
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fsrp->regs[PC_REGNUM] = fip->frame + 4;
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fsrp->regs[FP_REGNUM] = fip->frame;
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}
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|
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/* return pc of first real instruction */
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int
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i386_skip_prologue (pc)
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int pc;
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{
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unsigned char op;
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int i;
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static unsigned char pic_pat[6] =
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{0xe8, 0, 0, 0, 0, /* call 0x0 */
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0x5b, /* popl %ebx */
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};
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CORE_ADDR pos;
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|
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if (i386_get_frame_setup (pc) < 0)
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return (pc);
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/* found valid frame setup - codestream now points to
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* start of push instructions for saving registers
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*/
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|
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/* skip over register saves */
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for (i = 0; i < 8; i++)
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{
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op = codestream_peek ();
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/* break if not pushl inst */
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if (op < 0x50 || op > 0x57)
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break;
|
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codestream_get ();
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}
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|
|
/* 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
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|
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 ());
|
|
}
|
|
|
|
void
|
|
i386_push_dummy_frame ()
|
|
{
|
|
CORE_ADDR sp = read_register (SP_REGNUM);
|
|
int regnum;
|
|
char regbuf[MAX_REGISTER_RAW_SIZE];
|
|
|
|
sp = push_word (sp, read_register (PC_REGNUM));
|
|
sp = push_word (sp, read_register (FP_REGNUM));
|
|
write_register (FP_REGNUM, sp);
|
|
for (regnum = 0; regnum < NUM_REGS; regnum++)
|
|
{
|
|
read_register_gen (regnum, regbuf);
|
|
sp = push_bytes (sp, regbuf, REGISTER_RAW_SIZE (regnum));
|
|
}
|
|
write_register (SP_REGNUM, sp);
|
|
}
|
|
|
|
void
|
|
i386_pop_frame ()
|
|
{
|
|
struct frame_info *frame = get_current_frame ();
|
|
CORE_ADDR fp;
|
|
int regnum;
|
|
struct frame_saved_regs fsr;
|
|
char regbuf[MAX_REGISTER_RAW_SIZE];
|
|
|
|
fp = FRAME_FP (frame);
|
|
get_frame_saved_regs (frame, &fsr);
|
|
for (regnum = 0; regnum < NUM_REGS; regnum++)
|
|
{
|
|
CORE_ADDR adr;
|
|
adr = fsr.regs[regnum];
|
|
if (adr)
|
|
{
|
|
read_memory (adr, regbuf, REGISTER_RAW_SIZE (regnum));
|
|
write_register_bytes (REGISTER_BYTE (regnum), regbuf,
|
|
REGISTER_RAW_SIZE (regnum));
|
|
}
|
|
}
|
|
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 ();
|
|
}
|
|
|
|
#ifdef GET_LONGJMP_TARGET
|
|
|
|
/* 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 pc (JB_PC) that we will land at. The pc is copied into PC.
|
|
This routine returns true on success. */
|
|
|
|
int
|
|
get_longjmp_target (pc)
|
|
CORE_ADDR *pc;
|
|
{
|
|
char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
|
|
CORE_ADDR sp, jb_addr;
|
|
|
|
sp = read_register (SP_REGNUM);
|
|
|
|
if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack */
|
|
buf,
|
|
TARGET_PTR_BIT / TARGET_CHAR_BIT))
|
|
return 0;
|
|
|
|
jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
|
|
|
|
if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf,
|
|
TARGET_PTR_BIT / TARGET_CHAR_BIT))
|
|
return 0;
|
|
|
|
*pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
|
|
|
|
return 1;
|
|
}
|
|
|
|
#endif /* GET_LONGJMP_TARGET */
|
|
|
|
void
|
|
i386_extract_return_value (type, regbuf, valbuf)
|
|
struct type *type;
|
|
char regbuf[REGISTER_BYTES];
|
|
char *valbuf;
|
|
{
|
|
/* On AIX, floating point values are returned in floating point registers. */
|
|
#ifdef I386_AIX_TARGET
|
|
if (TYPE_CODE_FLT == TYPE_CODE (type))
|
|
{
|
|
double d;
|
|
/* 387 %st(0), gcc uses this */
|
|
floatformat_to_double (&floatformat_i387_ext,
|
|
®buf[REGISTER_BYTE (FP0_REGNUM)],
|
|
&d);
|
|
store_floating (valbuf, TYPE_LENGTH (type), d);
|
|
}
|
|
else
|
|
#endif /* I386_AIX_TARGET */
|
|
{
|
|
memcpy (valbuf, regbuf, TYPE_LENGTH (type));
|
|
}
|
|
}
|
|
|
|
#ifdef I386V4_SIGTRAMP_SAVED_PC
|
|
/* Get saved user PC for sigtramp from the pushed ucontext on the stack
|
|
for all three variants of SVR4 sigtramps. */
|
|
|
|
CORE_ADDR
|
|
i386v4_sigtramp_saved_pc (frame)
|
|
struct frame_info *frame;
|
|
{
|
|
CORE_ADDR saved_pc_offset = 4;
|
|
char *name = NULL;
|
|
|
|
find_pc_partial_function (frame->pc, &name, NULL, NULL);
|
|
if (name)
|
|
{
|
|
if (STREQ (name, "_sigreturn"))
|
|
saved_pc_offset = 132 + 14 * 4;
|
|
else if (STREQ (name, "_sigacthandler"))
|
|
saved_pc_offset = 80 + 14 * 4;
|
|
else if (STREQ (name, "sigvechandler"))
|
|
saved_pc_offset = 120 + 14 * 4;
|
|
}
|
|
|
|
if (frame->next)
|
|
return read_memory_integer (frame->next->frame + saved_pc_offset, 4);
|
|
return read_memory_integer (read_register (SP_REGNUM) + saved_pc_offset, 4);
|
|
}
|
|
#endif /* I386V4_SIGTRAMP_SAVED_PC */
|
|
|
|
#ifdef I386_LINUX_SIGTRAMP
|
|
|
|
/* When the i386 Linux kernel calls a signal handler, the return
|
|
address points to a bit of code on the stack. This function
|
|
returns whether the PC appears to be within this bit of code.
|
|
|
|
The instruction sequence is
|
|
pop %eax
|
|
mov $0x77,%eax
|
|
int $0x80
|
|
or 0x58 0xb8 0x77 0x00 0x00 0x00 0xcd 0x80.
|
|
|
|
Checking for the code sequence should be somewhat reliable, because
|
|
the effect is to call the system call sigreturn. This is unlikely
|
|
to occur anywhere other than a signal trampoline.
|
|
|
|
It kind of sucks that we have to read memory from the process in
|
|
order to identify a signal trampoline, but there doesn't seem to be
|
|
any other way. The IN_SIGTRAMP macro in tm-linux.h arranges to
|
|
only call us if no function name could be identified, which should
|
|
be the case since the code is on the stack. */
|
|
|
|
#define LINUX_SIGTRAMP_INSN0 (0x58) /* pop %eax */
|
|
#define LINUX_SIGTRAMP_OFFSET0 (0)
|
|
#define LINUX_SIGTRAMP_INSN1 (0xb8) /* mov $NNNN,%eax */
|
|
#define LINUX_SIGTRAMP_OFFSET1 (1)
|
|
#define LINUX_SIGTRAMP_INSN2 (0xcd) /* int */
|
|
#define LINUX_SIGTRAMP_OFFSET2 (6)
|
|
|
|
static const unsigned char linux_sigtramp_code[] =
|
|
{
|
|
LINUX_SIGTRAMP_INSN0, /* pop %eax */
|
|
LINUX_SIGTRAMP_INSN1, 0x77, 0x00, 0x00, 0x00, /* mov $0x77,%eax */
|
|
LINUX_SIGTRAMP_INSN2, 0x80 /* int $0x80 */
|
|
};
|
|
|
|
#define LINUX_SIGTRAMP_LEN (sizeof linux_sigtramp_code)
|
|
|
|
/* If PC is in a sigtramp routine, return the address of the start of
|
|
the routine. Otherwise, return 0. */
|
|
|
|
static CORE_ADDR
|
|
i386_linux_sigtramp_start (pc)
|
|
CORE_ADDR pc;
|
|
{
|
|
unsigned char buf[LINUX_SIGTRAMP_LEN];
|
|
|
|
/* We only recognize a signal trampoline if PC is at the start of
|
|
one of the three instructions. We optimize for finding the PC at
|
|
the start, as will be the case when the trampoline is not the
|
|
first frame on the stack. We assume that in the case where the
|
|
PC is not at the start of the instruction sequence, there will be
|
|
a few trailing readable bytes on the stack. */
|
|
|
|
if (read_memory_nobpt (pc, (char *) buf, LINUX_SIGTRAMP_LEN) != 0)
|
|
return 0;
|
|
|
|
if (buf[0] != LINUX_SIGTRAMP_INSN0)
|
|
{
|
|
int adjust;
|
|
|
|
switch (buf[0])
|
|
{
|
|
case LINUX_SIGTRAMP_INSN1:
|
|
adjust = LINUX_SIGTRAMP_OFFSET1;
|
|
break;
|
|
case LINUX_SIGTRAMP_INSN2:
|
|
adjust = LINUX_SIGTRAMP_OFFSET2;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
pc -= adjust;
|
|
|
|
if (read_memory_nobpt (pc, (char *) buf, LINUX_SIGTRAMP_LEN) != 0)
|
|
return 0;
|
|
}
|
|
|
|
if (memcmp (buf, linux_sigtramp_code, LINUX_SIGTRAMP_LEN) != 0)
|
|
return 0;
|
|
|
|
return pc;
|
|
}
|
|
|
|
/* Return whether PC is in a Linux sigtramp routine. */
|
|
|
|
int
|
|
i386_linux_sigtramp (pc)
|
|
CORE_ADDR pc;
|
|
{
|
|
return i386_linux_sigtramp_start (pc) != 0;
|
|
}
|
|
|
|
/* Assuming FRAME is for a Linux sigtramp routine, return the saved
|
|
program counter. The Linux kernel will set up a sigcontext
|
|
structure immediately before the sigtramp routine on the stack. */
|
|
|
|
CORE_ADDR
|
|
i386_linux_sigtramp_saved_pc (frame)
|
|
struct frame_info *frame;
|
|
{
|
|
CORE_ADDR pc;
|
|
|
|
pc = i386_linux_sigtramp_start (frame->pc);
|
|
if (pc == 0)
|
|
error ("i386_linux_sigtramp_saved_pc called when no sigtramp");
|
|
return read_memory_integer ((pc
|
|
- LINUX_SIGCONTEXT_SIZE
|
|
+ LINUX_SIGCONTEXT_PC_OFFSET),
|
|
4);
|
|
}
|
|
|
|
/* Assuming FRAME is for a Linux sigtramp routine, return the saved
|
|
stack pointer. The Linux kernel will set up a sigcontext structure
|
|
immediately before the sigtramp routine on the stack. */
|
|
|
|
CORE_ADDR
|
|
i386_linux_sigtramp_saved_sp (frame)
|
|
struct frame_info *frame;
|
|
{
|
|
CORE_ADDR pc;
|
|
|
|
pc = i386_linux_sigtramp_start (frame->pc);
|
|
if (pc == 0)
|
|
error ("i386_linux_sigtramp_saved_sp called when no sigtramp");
|
|
return read_memory_integer ((pc
|
|
- LINUX_SIGCONTEXT_SIZE
|
|
+ LINUX_SIGCONTEXT_SP_OFFSET),
|
|
4);
|
|
}
|
|
|
|
#endif /* I386_LINUX_SIGTRAMP */
|
|
|
|
#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 (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
|
|
skip_trampoline_code (pc, name)
|
|
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_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 */
|
|
}
|
|
|
|
static int
|
|
gdb_print_insn_i386 (memaddr, info)
|
|
bfd_vma memaddr;
|
|
disassemble_info *info;
|
|
{
|
|
if (disassembly_flavor == att_flavor)
|
|
return print_insn_i386_att (memaddr, info);
|
|
else if (disassembly_flavor == intel_flavor)
|
|
return print_insn_i386_intel (memaddr, info);
|
|
/* Never reached - disassembly_flavour is always either att_flavor
|
|
or intel_flavor */
|
|
abort ();
|
|
}
|
|
|
|
/* If the disassembly mode is intel, we have to also switch the
|
|
bfd mach_type. This function is run in the set disassembly_flavor
|
|
command, and does that. */
|
|
|
|
static void
|
|
set_disassembly_flavor_sfunc (args, from_tty, c)
|
|
char *args;
|
|
int from_tty;
|
|
struct cmd_list_element *c;
|
|
{
|
|
set_disassembly_flavor ();
|
|
|
|
if (disassembly_flavor_hook != NULL)
|
|
disassembly_flavor_hook (args, from_tty);
|
|
}
|
|
|
|
static void
|
|
set_disassembly_flavor ()
|
|
{
|
|
if (disassembly_flavor == att_flavor)
|
|
set_architecture_from_arch_mach (bfd_arch_i386, bfd_mach_i386_i386);
|
|
else if (disassembly_flavor == intel_flavor)
|
|
set_architecture_from_arch_mach (bfd_arch_i386, bfd_mach_i386_i386_intel_syntax);
|
|
}
|
|
|
|
void
|
|
_initialize_i386_tdep ()
|
|
{
|
|
struct cmd_list_element *new_cmd;
|
|
|
|
tm_print_insn = gdb_print_insn_i386;
|
|
tm_print_insn_info.mach = bfd_lookup_arch (bfd_arch_i386, 0)->mach;
|
|
|
|
/* Add the variable that controls the disassembly flavor */
|
|
|
|
new_cmd = add_set_enum_cmd ("disassembly-flavor", no_class,
|
|
valid_flavors,
|
|
(char *) &disassembly_flavor,
|
|
"Set the disassembly flavor, the valid values are \"att\" and \"intel\", \
|
|
and the default value is \"att\".",
|
|
&setlist);
|
|
new_cmd->function.sfunc = set_disassembly_flavor_sfunc;
|
|
add_show_from_set (new_cmd, &showlist);
|
|
|
|
/* Finally, initialize the disassembly flavor to the default given
|
|
in the disassembly_flavor variable */
|
|
|
|
set_disassembly_flavor ();
|
|
|
|
}
|