bfd/cpu-i386.c

   1 /* BFD support for the Intel 386 architecture.
   2    Copyright 1992, 1994, 1995, 1996, 1998, 2000, 2001, 2002, 2004, 2005,
   3    2007, 2009, 2010, 2011
   4    Free Software Foundation, Inc.
   5
   6    This file is part of BFD, the Binary File Descriptor library.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23 #include "sysdep.h"
  24 #include "bfd.h"
  25 #include "libbfd.h"
  26 #include "libiberty.h"
  27
  28 extern void * bfd_arch_i386_fill (bfd_size_type, bfd_boolean, bfd_boolean);
  29
  30 static const bfd_arch_info_type *
  31 bfd_i386_compatible (const bfd_arch_info_type *a,
  32                      const bfd_arch_info_type *b)
  33 {
  34   const bfd_arch_info_type *compat = bfd_default_compatible (a, b);
  35
  36   /* Don't allow mixing x64_32 with x86_64.  */
  37   if (compat
  38       && (a->mach & bfd_mach_x64_32) != (b->mach & bfd_mach_x64_32))
  39     compat = NULL;
  40
  41   return compat;
  42 }
  43
  44 /* Fill the buffer with zero or nop instruction if CODE is TRUE.  */
  45
  46 void *
  47 bfd_arch_i386_fill (bfd_size_type count,
  48                     bfd_boolean is_bigendian ATTRIBUTE_UNUSED,
  49                     bfd_boolean code)
  50 {
  51   /* nop */
  52   static const char nop_1[] = { 0x90 };
  53   /* nopw */
  54   static const char nop_2[] = { 0x66, 0x90 };
  55   /* nopl (%[re]ax) */
  56   static const char nop_3[] = { 0x0f, 0x1f, 0x00 };
  57   /* nopl 0(%[re]ax) */
  58   static const char nop_4[] = { 0x0f, 0x1f, 0x40, 0x00 };
  59   /* nopl 0(%[re]ax,%[re]ax,1) */
  60   static const char nop_5[] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 };
  61   /* nopw 0(%[re]ax,%[re]ax,1) */
  62   static const char nop_6[] = { 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00 };
  63   /* nopl 0L(%[re]ax) */
  64   static const char nop_7[] = { 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00 };
  65   /* nopl 0L(%[re]ax,%[re]ax,1) */
  66   static const char nop_8[] =
  67     { 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00};
  68   /* nopw 0L(%[re]ax,%[re]ax,1) */
  69   static const char nop_9[] =
  70     { 0x66, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 };
  71   /* nopw %cs:0L(%[re]ax,%[re]ax,1) */
  72   static const char nop_10[] =
  73     { 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 };
  74   static const char *const nops[] =
  75     { nop_1, nop_2, nop_3, nop_4, nop_5,
  76       nop_6, nop_7, nop_8, nop_9, nop_10 };
  77
  78   void *fill = bfd_malloc (count);
  79   if (fill == NULL)
  80     return fill;
  81
  82   if (code)
  83     {
  84       bfd_byte *p = fill;
  85       while (count >= ARRAY_SIZE (nops))
  86         {
  87           memcpy (p, nops[ARRAY_SIZE (nops) - 1], ARRAY_SIZE (nops));
  88           p += ARRAY_SIZE (nops);
  89           count -= ARRAY_SIZE (nops);
  90         }
  91       if (count != 0)
  92         memcpy (p, nops[count - 1], count);
  93     }
  94   else
  95     memset (fill, 0, count);
  96
  97   return fill;
  98 }
  99
 100 static const bfd_arch_info_type bfd_x64_32_arch_intel_syntax =
 101 {
 102   64, /* 64 bits in a word */
 103   64, /* 64 bits in an address */
 104   8,  /* 8 bits in a byte */
 105   bfd_arch_i386,
 106   bfd_mach_x64_32_intel_syntax,
 107   "i386:intel",
 108   "i386:x64-32:intel",
 109   3,
 110   FALSE,
 111   bfd_i386_compatible,
 112   bfd_default_scan,
 113   bfd_arch_i386_fill,
 114   0
 115 };
 116
 117 static const bfd_arch_info_type bfd_x86_64_arch_intel_syntax =
 118 {
 119   64, /* 64 bits in a word */
 120   64, /* 64 bits in an address */
 121   8,  /* 8 bits in a byte */
 122   bfd_arch_i386,
 123   bfd_mach_x86_64_intel_syntax,
 124   "i386:intel",
 125   "i386:x86-64:intel",
 126   3,
 127   FALSE,
 128   bfd_i386_compatible,
 129   bfd_default_scan,
 130   bfd_arch_i386_fill,
 131   &bfd_x64_32_arch_intel_syntax,
 132 };
 133
 134 static const bfd_arch_info_type bfd_i386_arch_intel_syntax =
 135 {
 136   32,   /* 32 bits in a word */
 137   32,   /* 32 bits in an address */
 138   8,    /* 8 bits in a byte */
 139   bfd_arch_i386,
 140   bfd_mach_i386_i386_intel_syntax,
 141   "i386:intel",
 142   "i386:intel",
 143   3,
 144   TRUE,
 145   bfd_i386_compatible,
 146   bfd_default_scan,
 147   bfd_arch_i386_fill,
 148   &bfd_x86_64_arch_intel_syntax
 149 };
 150
 151 static const bfd_arch_info_type i8086_arch =
 152 {
 153   32,   /* 32 bits in a word */
 154   32,   /* 32 bits in an address (well, not really) */
 155   8,    /* 8 bits in a byte */
 156   bfd_arch_i386,
 157   bfd_mach_i386_i8086,
 158   "i8086",
 159   "i8086",
 160   3,
 161   FALSE,
 162   bfd_i386_compatible,
 163   bfd_default_scan,
 164   bfd_arch_i386_fill,
 165   &bfd_i386_arch_intel_syntax
 166 };
 167
 168 static const bfd_arch_info_type bfd_x64_32_arch =
 169 {
 170   64, /* 64 bits in a word */
 171   64, /* 64 bits in an address */
 172   8,  /* 8 bits in a byte */
 173   bfd_arch_i386,
 174   bfd_mach_x64_32,
 175   "i386",
 176   "i386:x64-32",
 177   3,
 178   FALSE,
 179   bfd_i386_compatible,
 180   bfd_default_scan,
 181   bfd_arch_i386_fill,
 182   &i8086_arch
 183 };
 184
 185 static const bfd_arch_info_type bfd_x86_64_arch =
 186 {
 187   64, /* 64 bits in a word */
 188   64, /* 64 bits in an address */
 189   8,  /* 8 bits in a byte */
 190   bfd_arch_i386,
 191   bfd_mach_x86_64,
 192   "i386",
 193   "i386:x86-64",
 194   3,
 195   FALSE,
 196   bfd_i386_compatible,
 197   bfd_default_scan,
 198   bfd_arch_i386_fill,
 199   &bfd_x64_32_arch
 200 };
 201
 202 const bfd_arch_info_type bfd_i386_arch =
 203 {
 204   32,   /* 32 bits in a word */
 205   32,   /* 32 bits in an address */
 206   8,    /* 8 bits in a byte */
 207   bfd_arch_i386,
 208   bfd_mach_i386_i386,
 209   "i386",
 210   "i386",
 211   3,
 212   TRUE,
 213   bfd_i386_compatible,
 214   bfd_default_scan,
 215   bfd_arch_i386_fill,
 216   &bfd_x86_64_arch
 217 };