1 /* Native-dependent code for AMD64. 2 3 Copyright (C) 2003-2024 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 19 20 #include "gdbarch.h" 21 #include "regcache.h" 22 23 #include "i386-tdep.h" 24 #include "amd64-tdep.h" 25 #include "amd64-nat.h" 26 27 /* The following bits of code help with implementing debugging 32-bit 28 code natively on AMD64. The idea is to define two mappings between 29 the register number as used by GDB and the register set used by the 30 host to represent the general-purpose registers; one for 32-bit 31 code and one for 64-bit code. The mappings are specified by the 32 following variables and consist of an array of offsets within the 33 register set indexed by register number, and the number of 34 registers supported by the mapping. We don't need mappings for the 35 floating-point and SSE registers, since the difference between 36 64-bit and 32-bit variants are negligible. The difference in the 37 number of SSE registers is already handled by the target code. */ 38 39 /* General-purpose register mapping for native 32-bit code. */ 40 int *amd64_native_gregset32_reg_offset; 41 int amd64_native_gregset32_num_regs = I386_NUM_GREGS; 42 43 /* General-purpose register mapping for native 64-bit code. */ 44 int *amd64_native_gregset64_reg_offset; 45 int amd64_native_gregset64_num_regs = AMD64_NUM_GREGS; 46 47 /* Return the offset of REGNUM within the appropriate native 48 general-purpose register set. */ 49 50 static int 51 amd64_native_gregset_reg_offset (struct gdbarch *gdbarch, int regnum) 52 { 53 int *reg_offset = amd64_native_gregset64_reg_offset; 54 int num_regs = amd64_native_gregset64_num_regs; 55 56 gdb_assert (regnum >= 0); 57 58 if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32) 59 { 60 reg_offset = amd64_native_gregset32_reg_offset; 61 num_regs = amd64_native_gregset32_num_regs; 62 } 63 64 if (num_regs > gdbarch_num_regs (gdbarch)) 65 num_regs = gdbarch_num_regs (gdbarch); 66 67 if (regnum >= num_regs) 68 return -1; 69 70 return reg_offset[regnum]; 71 } 72 73 /* Return whether the native general-purpose register set supplies 74 register REGNUM. */ 75 76 int 77 amd64_native_gregset_supplies_p (struct gdbarch *gdbarch, int regnum) 78 { 79 return (amd64_native_gregset_reg_offset (gdbarch, regnum) != -1); 80 } 81 82 83 /* Supply register REGNUM, whose contents are stored in GREGS, to 84 REGCACHE. If REGNUM is -1, supply all appropriate registers. */ 85 86 void 87 amd64_supply_native_gregset (struct regcache *regcache, 88 const void *gregs, int regnum) 89 { 90 const char *regs = (const char *) gregs; 91 struct gdbarch *gdbarch = regcache->arch (); 92 int num_regs = amd64_native_gregset64_num_regs; 93 int i; 94 95 if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32) 96 num_regs = amd64_native_gregset32_num_regs; 97 98 if (num_regs > gdbarch_num_regs (gdbarch)) 99 num_regs = gdbarch_num_regs (gdbarch); 100 101 for (i = 0; i < num_regs; i++) 102 { 103 if (regnum == -1 || regnum == i) 104 { 105 int offset = amd64_native_gregset_reg_offset (gdbarch, i); 106 107 if (offset != -1) 108 regcache->raw_supply (i, regs + offset); 109 } 110 } 111 } 112 113 /* Collect register REGNUM from REGCACHE and store its contents in 114 GREGS. If REGNUM is -1, collect and store all appropriate 115 registers. */ 116 117 void 118 amd64_collect_native_gregset (const struct regcache *regcache, 119 void *gregs, int regnum) 120 { 121 char *regs = (char *) gregs; 122 struct gdbarch *gdbarch = regcache->arch (); 123 int num_regs = amd64_native_gregset64_num_regs; 124 int i; 125 126 if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32) 127 { 128 num_regs = amd64_native_gregset32_num_regs; 129 130 /* Make sure %eax, %ebx, %ecx, %edx, %esi, %edi, %ebp, %esp and 131 %eip get zero-extended to 64 bits. */ 132 for (i = 0; i <= I386_EIP_REGNUM; i++) 133 { 134 if (regnum == -1 || regnum == i) 135 memset (regs + amd64_native_gregset_reg_offset (gdbarch, i), 0, 8); 136 } 137 /* Ditto for %cs, %ss, %ds, %es, %fs, and %gs. */ 138 for (i = I386_CS_REGNUM; i <= I386_GS_REGNUM; i++) 139 { 140 if (regnum == -1 || regnum == i) 141 memset (regs + amd64_native_gregset_reg_offset (gdbarch, i), 0, 8); 142 } 143 } 144 145 if (num_regs > gdbarch_num_regs (gdbarch)) 146 num_regs = gdbarch_num_regs (gdbarch); 147 148 for (i = 0; i < num_regs; i++) 149 { 150 if (regnum == -1 || regnum == i) 151 { 152 int offset = amd64_native_gregset_reg_offset (gdbarch, i); 153 154 if (offset != -1) 155 regcache->raw_collect (i, regs + offset); 156 } 157 } 158 } 159