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/tmp/gdb-7.10/gdb/amd64-nat.c
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1 /* Native-dependent code for AMD64.
2 
3  Copyright (C) 2003-2015 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 "defs.h"
21 #include "gdbarch.h"
22 #include "regcache.h"
23 
24 #include "i386-tdep.h"
25 #include "amd64-tdep.h"
26 #include "amd64-nat.h"
27 
28 /* The following bits of code help with implementing debugging 32-bit
29  code natively on AMD64. The idea is to define two mappings between
30  the register number as used by GDB and the register set used by the
31  host to represent the general-purpose registers; one for 32-bit
32  code and one for 64-bit code. The mappings are specified by the
33  follwing variables and consist of an array of offsets within the
34  register set indexed by register number, and the number of
35  registers supported by the mapping. We don't need mappings for the
36  floating-point and SSE registers, since the difference between
37  64-bit and 32-bit variants are negligable. The difference in the
38  number of SSE registers is already handled by the target code. */
39 
40 /* General-purpose register mapping for native 32-bit code. */
43 
44 /* General-purpose register mapping for native 64-bit code. */
47 
48 /* Return the offset of REGNUM within the appropriate native
49  general-purpose register set. */
50 
51 static int
53 {
56 
57  gdb_assert (regnum >= 0);
58 
59  if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32)
60  {
63  }
64 
65  if (num_regs > gdbarch_num_regs (gdbarch))
66  num_regs = gdbarch_num_regs (gdbarch);
67 
68  if (regnum < num_regs && regnum < gdbarch_num_regs (gdbarch))
69  return reg_offset[regnum];
70 
71  return -1;
72 }
73 
74 /* Return whether the native general-purpose register set supplies
75  register REGNUM. */
76 
77 int
79 {
80  return (amd64_native_gregset_reg_offset (gdbarch, regnum) != -1);
81 }
82 
83 
84 /* Supply register REGNUM, whose contents are stored in GREGS, to
85  REGCACHE. If REGNUM is -1, supply all appropriate registers. */
86 
87 void
89  const void *gregs, int regnum)
90 {
91  const char *regs = gregs;
92  struct gdbarch *gdbarch = get_regcache_arch (regcache);
94  int i;
95 
96  if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32)
98 
99  if (num_regs > gdbarch_num_regs (gdbarch))
100  num_regs = gdbarch_num_regs (gdbarch);
101 
102  for (i = 0; i < num_regs; i++)
103  {
104  if (regnum == -1 || regnum == i)
105  {
106  int offset = amd64_native_gregset_reg_offset (gdbarch, i);
107 
108  if (offset != -1)
109  regcache_raw_supply (regcache, i, regs + offset);
110  }
111  }
112 }
113 
114 /* Collect register REGNUM from REGCACHE and store its contents in
115  GREGS. If REGNUM is -1, collect and store all appropriate
116  registers. */
117 
118 void
120  void *gregs, int regnum)
121 {
122  char *regs = gregs;
123  struct gdbarch *gdbarch = get_regcache_arch (regcache);
125  int i;
126 
127  if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32)
128  {
130 
131  /* Make sure %eax, %ebx, %ecx, %edx, %esi, %edi, %ebp, %esp and
132  %eip get zero-extended to 64 bits. */
133  for (i = 0; i <= I386_EIP_REGNUM; i++)
134  {
135  if (regnum == -1 || regnum == i)
136  memset (regs + amd64_native_gregset_reg_offset (gdbarch, i), 0, 8);
137  }
138  /* Ditto for %cs, %ss, %ds, %es, %fs, and %gs. */
139  for (i = I386_CS_REGNUM; i <= I386_GS_REGNUM; i++)
140  {
141  if (regnum == -1 || regnum == i)
142  memset (regs + amd64_native_gregset_reg_offset (gdbarch, i), 0, 8);
143  }
144  }
145 
146  if (num_regs > gdbarch_num_regs (gdbarch))
147  num_regs = gdbarch_num_regs (gdbarch);
148 
149  for (i = 0; i < num_regs; i++)
150  {
151  if (regnum == -1 || regnum == i)
152  {
153  int offset = amd64_native_gregset_reg_offset (gdbarch, i);
154 
155  if (offset != -1)
156  regcache_raw_collect (regcache, i, regs + offset);
157  }
158  }
159 }
#define I386_NUM_GREGS
Definition: i386-tdep.h:320
int num_regs
Definition: gdbarch.c:188
struct gdbarch * get_regcache_arch(const struct regcache *regcache)
Definition: regcache.c:297
void amd64_collect_native_gregset(const struct regcache *regcache, void *gregs, int regnum)
Definition: amd64-nat.c:119
int amd64_native_gregset32_num_regs
Definition: amd64-nat.c:42
static int reg_offset[]
Definition: i386gnu-nat.c:42
int gdbarch_num_regs(struct gdbarch *gdbarch)
Definition: gdbarch.c:1898
int amd64_native_gregset64_num_regs
Definition: amd64-nat.c:46
void amd64_supply_native_gregset(struct regcache *regcache, const void *gregs, int regnum)
Definition: amd64-nat.c:88
int * amd64_native_gregset32_reg_offset
Definition: amd64-nat.c:41
int * amd64_native_gregset64_reg_offset
Definition: amd64-nat.c:45
#define AMD64_NUM_GREGS
Definition: amd64-tdep.h:83
#define gdb_assert(expr)
Definition: gdb_assert.h:33
int regnum
Definition: aarch64-tdep.c:69
static int amd64_native_gregset_reg_offset(struct gdbarch *gdbarch, int regnum)
Definition: amd64-nat.c:52
int amd64_native_gregset_supplies_p(struct gdbarch *gdbarch, int regnum)
Definition: amd64-nat.c:78
int offset
Definition: agent.c:65
void regcache_raw_supply(struct regcache *regcache, int regnum, const void *buf)
Definition: regcache.c:1041
const struct bfd_arch_info * gdbarch_bfd_arch_info(struct gdbarch *gdbarch)
Definition: gdbarch.c:1411
void regcache_raw_collect(const struct regcache *regcache, int regnum, void *buf)
Definition: regcache.c:1071