| /* BFD support for the Intel 386 architecture. |
| Copyright (C) 1992-2024 Free Software Foundation, Inc. |
| |
| This file is part of BFD, the Binary File Descriptor library. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| MA 02110-1301, USA. */ |
| |
| #include "sysdep.h" |
| #include "bfd.h" |
| #include "libbfd.h" |
| #include "libiberty.h" |
| |
| extern void * bfd_arch_i386_short_nop_fill (bfd_size_type, bool, |
| bool); |
| |
| static const bfd_arch_info_type * |
| bfd_i386_compatible (const bfd_arch_info_type *a, |
| const bfd_arch_info_type *b) |
| { |
| const bfd_arch_info_type *compat = bfd_default_compatible (a, b); |
| |
| /* Don't allow mixing x64_32 with x86_64. */ |
| if (compat |
| && (a->mach & bfd_mach_x64_32) != (b->mach & bfd_mach_x64_32)) |
| compat = NULL; |
| |
| return compat; |
| } |
| |
| /* Fill the buffer with zero or nop instruction if CODE is TRUE. Use |
| multi byte nop instructions if LONG_NOP is TRUE. */ |
| |
| static void * |
| bfd_arch_i386_fill (bfd_size_type count, bool code, |
| bool long_nop) |
| { |
| /* nop */ |
| static const char nop_1[] = { 0x90 }; |
| /* xchg %ax,%ax */ |
| static const char nop_2[] = { 0x66, 0x90 }; |
| /* nopl (%[re]ax) */ |
| static const char nop_3[] = { 0x0f, 0x1f, 0x00 }; |
| /* nopl 0(%[re]ax) */ |
| static const char nop_4[] = { 0x0f, 0x1f, 0x40, 0x00 }; |
| /* nopl 0(%[re]ax,%[re]ax,1) */ |
| static const char nop_5[] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 }; |
| /* nopw 0(%[re]ax,%[re]ax,1) */ |
| static const char nop_6[] = { 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00 }; |
| /* nopl 0L(%[re]ax) */ |
| static const char nop_7[] = { 0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00 }; |
| /* nopl 0L(%[re]ax,%[re]ax,1) */ |
| static const char nop_8[] = |
| { 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00}; |
| /* nopw 0L(%[re]ax,%[re]ax,1) */ |
| static const char nop_9[] = |
| { 0x66, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 }; |
| /* nopw %cs:0L(%[re]ax,%[re]ax,1) */ |
| static const char nop_10[] = |
| { 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 }; |
| static const char *const nops[] = |
| { nop_1, nop_2, nop_3, nop_4, nop_5, |
| nop_6, nop_7, nop_8, nop_9, nop_10 }; |
| bfd_size_type nop_size = long_nop ? ARRAY_SIZE (nops) : 2; |
| |
| void *fill = bfd_malloc (count); |
| if (fill == NULL) |
| return fill; |
| |
| if (code) |
| { |
| bfd_byte *p = fill; |
| while (count >= nop_size) |
| { |
| memcpy (p, nops[nop_size - 1], nop_size); |
| p += nop_size; |
| count -= nop_size; |
| } |
| if (count != 0) |
| memcpy (p, nops[count - 1], count); |
| } |
| else |
| memset (fill, 0, count); |
| |
| return fill; |
| } |
| |
| /* Fill the buffer with zero or short nop instruction if CODE is true. */ |
| |
| void * |
| bfd_arch_i386_short_nop_fill (bfd_size_type count, |
| bool is_bigendian ATTRIBUTE_UNUSED, |
| bool code) |
| { |
| return bfd_arch_i386_fill (count, code, false); |
| } |
| |
| /* Fill the buffer with zero or long nop instruction if CODE is TRUE. */ |
| |
| static void * |
| bfd_arch_i386_long_nop_fill (bfd_size_type count, |
| bool is_bigendian ATTRIBUTE_UNUSED, |
| bool code) |
| { |
| return bfd_arch_i386_fill (count, code, true); |
| } |
| |
| #define N(BITS, MACH, NAME, PRINT, DEF, FILL, NEXT) \ |
| { BITS, /* Bits in a word. */ \ |
| BITS, /* Bits in an address. */ \ |
| 8, /* Bits in a byte. */ \ |
| bfd_arch_i386, \ |
| MACH, /* Machine number. */ \ |
| NAME, \ |
| PRINT, \ |
| 3, /* Section alignment power. */ \ |
| DEF, /* Default architecture version ? */ \ |
| bfd_i386_compatible, \ |
| bfd_default_scan, \ |
| FILL, \ |
| NEXT, \ |
| 0 /* Maximum instruction length. */ \ |
| } |
| |
| |
| static const bfd_arch_info_type bfd_x64_32_arch_intel_syntax = |
| N (64, bfd_mach_x64_32_intel_syntax, "i386:intel", "i386:x64-32:intel", |
| false, bfd_arch_i386_long_nop_fill, NULL); |
| |
| static const bfd_arch_info_type bfd_x86_64_arch_intel_syntax = |
| N (64, bfd_mach_x86_64_intel_syntax, "i386:intel", "i386:x86-64:intel", |
| false, bfd_arch_i386_long_nop_fill, &bfd_x64_32_arch_intel_syntax); |
| |
| static const bfd_arch_info_type bfd_i386_arch_intel_syntax = |
| N (32, bfd_mach_i386_i386_intel_syntax, "i386:intel", "i386:intel", |
| true, bfd_arch_i386_short_nop_fill, &bfd_x86_64_arch_intel_syntax); |
| |
| |
| static const bfd_arch_info_type i8086_arch = |
| N (32, bfd_mach_i386_i8086, "i8086", "i8086", |
| false, bfd_arch_i386_short_nop_fill, &bfd_i386_arch_intel_syntax); |
| |
| static const bfd_arch_info_type bfd_x64_32_arch = |
| N (64, bfd_mach_x64_32, "i386", "i386:x64-32", |
| false, bfd_arch_i386_long_nop_fill, &i8086_arch); |
| |
| static const bfd_arch_info_type bfd_x86_64_arch = |
| N (64, bfd_mach_x86_64, "i386", "i386:x86-64", |
| false, bfd_arch_i386_long_nop_fill, &bfd_x64_32_arch); |
| |
| const bfd_arch_info_type bfd_i386_arch = |
| N (32, bfd_mach_i386_i386, "i386", "i386", |
| true, bfd_arch_i386_short_nop_fill, &bfd_x86_64_arch); |