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, 2013
   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_short_nop_fill (bfd_size_type, bfd_boolean,
  29                                             bfd_boolean);
  30
  31 static const bfd_arch_info_type *
  32 bfd_i386_compatible (const bfd_arch_info_type *a,
  33                      const bfd_arch_info_type *b)
  34 {
  35   const bfd_arch_info_type *compat = bfd_default_compatible (a, b);
  36
  37   /* Don't allow mixing x64_32 with x86_64.  */
  38   if (compat
  39       && (a->mach & bfd_mach_x64_32) != (b->mach & bfd_mach_x64_32))
  40     compat = NULL;
  41
  42   return compat;
  43 }
  44
  45 /* Fill the buffer with zero or nop instruction if CODE is TRUE.  Use
  46    multi byte nop instructions if LONG_NOP is TRUE.  */
  47
  48 static void *
  49 bfd_arch_i386_fill (bfd_size_type count, bfd_boolean code,
  50                     bfd_boolean long_nop)
  51 {
  52   /* nop */
  53   static const char nop_1[] = { 0x90 };
  54   /* xchg %ax,%ax */
  55   static const char nop_2[] = { 0x66, 0x90 };
  56   /* nopl (%[re]ax) */
  57   static const char nop_3[] = { 0x0f, 0x1f, 0x00 };
  58   /* nopl 0(%[re]ax) */
  59   static const char nop_4[] = { 0x0f, 0x1f, 0x40, 0x00 };
  60   /* nopl 0(%[re]ax,%[re]ax,1) */
  61   static const char nop_5[] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 };
  62   /* nopw 0(%[re]ax,%[re]ax,1) */
  63   static const char nop_6[] = { 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00 };
  64   /* nopl 0L(%[re]ax) */
  65   static const char nop_7[] = { 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00 };
  66   /* nopl 0L(%[re]ax,%[re]ax,1) */
  67   static const char nop_8[] =
  68     { 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00};
  69   /* nopw 0L(%[re]ax,%[re]ax,1) */
  70   static const char nop_9[] =
  71     { 0x66, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 };
  72   /* nopw %cs:0L(%[re]ax,%[re]ax,1) */
  73   static const char nop_10[] =
  74     { 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 };
  75   static const char *const nops[] =
  76     { nop_1, nop_2, nop_3, nop_4, nop_5,
  77       nop_6, nop_7, nop_8, nop_9, nop_10 };
  78   bfd_size_type nop_size = long_nop ? ARRAY_SIZE (nops) : 2;
  79
  80   void *fill = bfd_malloc (count);
  81   if (fill == NULL)
  82     return fill;
  83
  84   if (code)
  85     {
  86       bfd_byte *p = fill;
  87       while (count >= nop_size)
  88         {
  89           memcpy (p, nops[nop_size - 1], nop_size);
  90           p += nop_size;
  91           count -= nop_size;
  92         }
  93       if (count != 0)
  94         memcpy (p, nops[count - 1], count);
  95     }
  96   else
  97     memset (fill, 0, count);
  98
  99   return fill;
 100 }
 101
 102 /* Fill the buffer with zero or short nop instruction if CODE is TRUE.  */
 103
 104 void *
 105 bfd_arch_i386_short_nop_fill (bfd_size_type count,
 106                               bfd_boolean is_bigendian ATTRIBUTE_UNUSED,
 107                               bfd_boolean code)
 108 {
 109   return bfd_arch_i386_fill (count, code, FALSE);
 110 }
 111
 112 /* Fill the buffer with zero or long nop instruction if CODE is TRUE.  */
 113
 114 static void *
 115 bfd_arch_i386_long_nop_fill (bfd_size_type count,
 116                              bfd_boolean is_bigendian ATTRIBUTE_UNUSED,
 117                              bfd_boolean code)
 118 {
 119   return bfd_arch_i386_fill (count, code, TRUE);
 120 }
 121
 122 /* Fill the buffer with zero, or one-byte nop instructions if CODE is TRUE.  */
 123
 124 static void *
 125 bfd_arch_i386_onebyte_nop_fill (bfd_size_type count,
 126                                 bfd_boolean is_bigendian ATTRIBUTE_UNUSED,
 127                                 bfd_boolean code)
 128 {
 129   void *fill = bfd_malloc (count);
 130   if (fill != NULL)
 131     memset (fill, code ? 0x90 : 0, count);
 132   return fill;
 133 }
 134
 135
 136 static const bfd_arch_info_type bfd_x64_32_nacl_arch =
 137 {
 138   64, /* 64 bits in a word */
 139   64, /* 64 bits in an address */
 140   8,  /* 8 bits in a byte */
 141   bfd_arch_i386,
 142   bfd_mach_x64_32_nacl,
 143   "i386",
 144   "i386:x64-32:nacl",
 145   3,
 146   FALSE,
 147   bfd_i386_compatible,
 148   bfd_default_scan,
 149   bfd_arch_i386_onebyte_nop_fill,
 150   NULL
 151 };
 152
 153 static const bfd_arch_info_type bfd_x86_64_nacl_arch =
 154 {
 155   64, /* 64 bits in a word */
 156   64, /* 64 bits in an address */
 157   8,  /* 8 bits in a byte */
 158   bfd_arch_i386,
 159   bfd_mach_x86_64_nacl,
 160   "i386",
 161   "i386:x86-64:nacl",
 162   3,
 163   FALSE,
 164   bfd_i386_compatible,
 165   bfd_default_scan,
 166   bfd_arch_i386_onebyte_nop_fill,
 167   &bfd_x64_32_nacl_arch
 168 };
 169
 170 const bfd_arch_info_type bfd_i386_nacl_arch =
 171 {
 172   32,   /* 32 bits in a word */
 173   32,   /* 32 bits in an address */
 174   8,    /* 8 bits in a byte */
 175   bfd_arch_i386,
 176   bfd_mach_i386_i386_nacl,
 177   "i386",
 178   "i386:nacl",
 179   3,
 180   TRUE,
 181   bfd_i386_compatible,
 182   bfd_default_scan,
 183   bfd_arch_i386_onebyte_nop_fill,
 184   &bfd_x86_64_nacl_arch
 185 };
 186
 187 static const bfd_arch_info_type bfd_x64_32_arch_intel_syntax =
 188 {
 189   64, /* 64 bits in a word */
 190   64, /* 64 bits in an address */
 191   8,  /* 8 bits in a byte */
 192   bfd_arch_i386,
 193   bfd_mach_x64_32_intel_syntax,
 194   "i386:intel",
 195   "i386:x64-32:intel",
 196   3,
 197   FALSE,
 198   bfd_i386_compatible,
 199   bfd_default_scan,
 200   bfd_arch_i386_long_nop_fill,
 201   &bfd_i386_nacl_arch
 202 };
 203
 204 static const bfd_arch_info_type bfd_x86_64_arch_intel_syntax =
 205 {
 206   64, /* 64 bits in a word */
 207   64, /* 64 bits in an address */
 208   8,  /* 8 bits in a byte */
 209   bfd_arch_i386,
 210   bfd_mach_x86_64_intel_syntax,
 211   "i386:intel",
 212   "i386:x86-64:intel",
 213   3,
 214   FALSE,
 215   bfd_i386_compatible,
 216   bfd_default_scan,
 217   bfd_arch_i386_long_nop_fill,
 218   &bfd_x64_32_arch_intel_syntax,
 219 };
 220
 221 static const bfd_arch_info_type bfd_i386_arch_intel_syntax =
 222 {
 223   32,   /* 32 bits in a word */
 224   32,   /* 32 bits in an address */
 225   8,    /* 8 bits in a byte */
 226   bfd_arch_i386,
 227   bfd_mach_i386_i386_intel_syntax,
 228   "i386:intel",
 229   "i386:intel",
 230   3,
 231   TRUE,
 232   bfd_i386_compatible,
 233   bfd_default_scan,
 234   bfd_arch_i386_short_nop_fill,
 235   &bfd_x86_64_arch_intel_syntax
 236 };
 237
 238 static const bfd_arch_info_type i8086_arch =
 239 {
 240   32,   /* 32 bits in a word */
 241   32,   /* 32 bits in an address (well, not really) */
 242   8,    /* 8 bits in a byte */
 243   bfd_arch_i386,
 244   bfd_mach_i386_i8086,
 245   "i8086",
 246   "i8086",
 247   3,
 248   FALSE,
 249   bfd_i386_compatible,
 250   bfd_default_scan,
 251   bfd_arch_i386_short_nop_fill,
 252   &bfd_i386_arch_intel_syntax
 253 };
 254
 255 static const bfd_arch_info_type bfd_x64_32_arch =
 256 {
 257   64, /* 64 bits in a word */
 258   64, /* 64 bits in an address */
 259   8,  /* 8 bits in a byte */
 260   bfd_arch_i386,
 261   bfd_mach_x64_32,
 262   "i386",
 263   "i386:x64-32",
 264   3,
 265   FALSE,
 266   bfd_i386_compatible,
 267   bfd_default_scan,
 268   bfd_arch_i386_long_nop_fill,
 269   &i8086_arch
 270 };
 271
 272 static const bfd_arch_info_type bfd_x86_64_arch =
 273 {
 274   64, /* 64 bits in a word */
 275   64, /* 64 bits in an address */
 276   8,  /* 8 bits in a byte */
 277   bfd_arch_i386,
 278   bfd_mach_x86_64,
 279   "i386",
 280   "i386:x86-64",
 281   3,
 282   FALSE,
 283   bfd_i386_compatible,
 284   bfd_default_scan,
 285   bfd_arch_i386_long_nop_fill,
 286   &bfd_x64_32_arch
 287 };
 288
 289 const bfd_arch_info_type bfd_i386_arch =
 290 {
 291   32,   /* 32 bits in a word */
 292   32,   /* 32 bits in an address */
 293   8,    /* 8 bits in a byte */
 294   bfd_arch_i386,
 295   bfd_mach_i386_i386,
 296   "i386",
 297   "i386",
 298   3,
 299   TRUE,
 300   bfd_i386_compatible,
 301   bfd_default_scan,
 302   bfd_arch_i386_short_nop_fill,
 303   &bfd_x86_64_arch
 304 };