1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
|
/* Target-dependent code for FreeBSD/arm.
Copyright (C) 2017-2021 Free Software Foundation, Inc.
This file is part of GDB.
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, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "elf/common.h"
#include "target-descriptions.h"
#include "aarch32-tdep.h"
#include "arm-tdep.h"
#include "arm-fbsd-tdep.h"
#include "auxv.h"
#include "fbsd-tdep.h"
#include "gdbcore.h"
#include "osabi.h"
#include "solib-svr4.h"
#include "trad-frame.h"
#include "tramp-frame.h"
/* Register maps. */
static const struct regcache_map_entry arm_fbsd_gregmap[] =
{
{ 13, ARM_A1_REGNUM, 4 }, /* r0 ... r12 */
{ 1, ARM_SP_REGNUM, 4 },
{ 1, ARM_LR_REGNUM, 4 },
{ 1, ARM_PC_REGNUM, 4 },
{ 1, ARM_PS_REGNUM, 4 },
{ 0 }
};
static const struct regcache_map_entry arm_fbsd_vfpregmap[] =
{
{ 32, ARM_D0_REGNUM, 8 }, /* d0 ... d31 */
{ 1, ARM_FPSCR_REGNUM, 4 },
{ 0 }
};
/* In a signal frame, sp points to a 'struct sigframe' which is
defined as:
struct sigframe {
siginfo_t sf_si;
ucontext_t sf_uc;
mcontext_vfp_t sf_vfp;
};
ucontext_t is defined as:
struct __ucontext {
sigset_t uc_sigmask;
mcontext_t uc_mcontext;
...
};
mcontext_t is defined as:
struct {
unsigned int __gregs[17];
size_t mc_vfp_size;
void *mc_vfp_ptr;
...
};
mcontext_vfp_t is defined as:
struct {
uint64_t mcv_reg[32];
uint32_t mcv_fpscr;
};
If the VFP state is valid, then mc_vfp_ptr will point to sf_vfp in
the sigframe, otherwise it is NULL. There is no non-VFP floating
point register state saved in the signal frame. */
#define ARM_SIGFRAME_UCONTEXT_OFFSET 64
#define ARM_UCONTEXT_MCONTEXT_OFFSET 16
#define ARM_MCONTEXT_VFP_PTR_OFFSET 72
/* Implement the "init" method of struct tramp_frame. */
static void
arm_fbsd_sigframe_init (const struct tramp_frame *self,
struct frame_info *this_frame,
struct trad_frame_cache *this_cache,
CORE_ADDR func)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR sp = get_frame_register_unsigned (this_frame, ARM_SP_REGNUM);
CORE_ADDR mcontext_addr = (sp
+ ARM_SIGFRAME_UCONTEXT_OFFSET
+ ARM_UCONTEXT_MCONTEXT_OFFSET);
ULONGEST mcontext_vfp_addr;
trad_frame_set_reg_regmap (this_cache, arm_fbsd_gregmap, mcontext_addr,
regcache_map_entry_size (arm_fbsd_gregmap));
if (safe_read_memory_unsigned_integer (mcontext_addr
+ ARM_MCONTEXT_VFP_PTR_OFFSET, 4,
byte_order,
&mcontext_vfp_addr)
&& mcontext_vfp_addr != 0)
trad_frame_set_reg_regmap (this_cache, arm_fbsd_vfpregmap, mcontext_vfp_addr,
regcache_map_entry_size (arm_fbsd_vfpregmap));
trad_frame_set_id (this_cache, frame_id_build (sp, func));
}
static const struct tramp_frame arm_fbsd_sigframe =
{
SIGTRAMP_FRAME,
4,
{
{0xe1a0000d, ULONGEST_MAX}, /* mov r0, sp */
{0xe2800040, ULONGEST_MAX}, /* add r0, r0, #SIGF_UC */
{0xe59f700c, ULONGEST_MAX}, /* ldr r7, [pc, #12] */
{0xef0001a1, ULONGEST_MAX}, /* swi SYS_sigreturn */
{TRAMP_SENTINEL_INSN, ULONGEST_MAX}
},
arm_fbsd_sigframe_init
};
/* Register set definitions. */
const struct regset arm_fbsd_gregset =
{
arm_fbsd_gregmap,
regcache_supply_regset, regcache_collect_regset
};
const struct regset arm_fbsd_vfpregset =
{
arm_fbsd_vfpregmap,
regcache_supply_regset, regcache_collect_regset
};
/* Implement the "iterate_over_regset_sections" gdbarch method. */
static void
arm_fbsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
iterate_over_regset_sections_cb *cb,
void *cb_data,
const struct regcache *regcache)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
cb (".reg", ARM_FBSD_SIZEOF_GREGSET, ARM_FBSD_SIZEOF_GREGSET,
&arm_fbsd_gregset, NULL, cb_data);
/* While FreeBSD/arm cores do contain a NT_FPREGSET / ".reg2"
register set, it is not populated with register values by the
kernel but just contains all zeroes. */
if (tdep->vfp_register_count > 0)
cb (".reg-arm-vfp", ARM_FBSD_SIZEOF_VFPREGSET, ARM_FBSD_SIZEOF_VFPREGSET,
&arm_fbsd_vfpregset, "VFP floating-point", cb_data);
}
/* Lookup a target description from a target's AT_HWCAP auxiliary
vector. */
const struct target_desc *
arm_fbsd_read_description_auxv (struct target_ops *target)
{
CORE_ADDR arm_hwcap = 0;
if (target_auxv_search (target, AT_FREEBSD_HWCAP, &arm_hwcap) != 1)
return nullptr;
if (arm_hwcap & HWCAP_VFP)
{
if (arm_hwcap & HWCAP_NEON)
return aarch32_read_description ();
else if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPD32))
== (HWCAP_VFPv3 | HWCAP_VFPD32))
return arm_read_description (ARM_FP_TYPE_VFPV3);
else
return arm_read_description (ARM_FP_TYPE_VFPV2);
}
return nullptr;
}
/* Implement the "core_read_description" gdbarch method. */
static const struct target_desc *
arm_fbsd_core_read_description (struct gdbarch *gdbarch,
struct target_ops *target,
bfd *abfd)
{
return arm_fbsd_read_description_auxv (target);
}
/* Implement the 'init_osabi' method of struct gdb_osabi_handler. */
static void
arm_fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
/* Generic FreeBSD support. */
fbsd_init_abi (info, gdbarch);
if (tdep->fp_model == ARM_FLOAT_AUTO)
tdep->fp_model = ARM_FLOAT_SOFT_VFP;
tramp_frame_prepend_unwinder (gdbarch, &arm_fbsd_sigframe);
set_solib_svr4_fetch_link_map_offsets
(gdbarch, svr4_ilp32_fetch_link_map_offsets);
tdep->jb_pc = 24;
tdep->jb_elt_size = 4;
set_gdbarch_iterate_over_regset_sections
(gdbarch, arm_fbsd_iterate_over_regset_sections);
set_gdbarch_core_read_description (gdbarch, arm_fbsd_core_read_description);
/* Single stepping. */
set_gdbarch_software_single_step (gdbarch, arm_software_single_step);
}
void _initialize_arm_fbsd_tdep ();
void
_initialize_arm_fbsd_tdep ()
{
gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_FREEBSD,
arm_fbsd_init_abi);
}
|