blob: fde4d1495e7b87c498e1470a4506633297ceeb3c (
plain)
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
|
/* Copyright (C) 2009-2013 Free Software Foundation, Inc.
Contributed by ARM Ltd.
This file 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, or (at your option) any
later version.
This file 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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#ifndef inhibit_libc
#include <signal.h>
#include <sys/ucontext.h>
#define MD_FALLBACK_FRAME_STATE_FOR aarch64_fallback_frame_state
static _Unwind_Reason_Code
aarch64_fallback_frame_state (struct _Unwind_Context *context,
_Unwind_FrameState * fs)
{
/* The kernel creates an rt_sigframe on the stack immediately prior
to delivering a signal.
This structure must have the same shape as the linux kernel
equivalent. */
struct rt_sigframe
{
siginfo_t info;
struct ucontext uc;
};
struct rt_sigframe *rt_;
_Unwind_Ptr new_cfa;
unsigned *pc = context->ra;
struct sigcontext *sc;
struct _aarch64_ctx *extension_marker;
int i;
/* A signal frame will have a return address pointing to
__default_sa_restorer. This code is hardwired as:
0xd2801168 movz x8, #0x8b
0xd4000001 svc 0x0
*/
if (pc[0] != 0xd2801168 || pc[1] != 0xd4000001)
{
return _URC_END_OF_STACK;
}
rt_ = context->cfa;
sc = &rt_->uc.uc_mcontext;
/* This define duplicates the definition in aarch64.md */
#define SP_REGNUM 31
new_cfa = (_Unwind_Ptr) sc;
fs->regs.cfa_how = CFA_REG_OFFSET;
fs->regs.cfa_reg = STACK_POINTER_REGNUM;
fs->regs.cfa_offset = new_cfa - (_Unwind_Ptr) context->cfa;
for (i = 0; i < AARCH64_DWARF_NUMBER_R; i++)
{
fs->regs.reg[AARCH64_DWARF_R0 + i].how = REG_SAVED_OFFSET;
fs->regs.reg[AARCH64_DWARF_R0 + i].loc.offset =
(_Unwind_Ptr) & (sc->regs[i]) - new_cfa;
}
/* The core context may be extended with an arbitrary set of
additional contexts appended sequentially. Each additional
context contains a magic identifier and size in bytes. The size
field can be used to skip over unrecognized context extensions.
The end of the context sequence is marked by a context with magic
0 or size 0. */
for (extension_marker = (struct _aarch64_ctx *) &sc->__reserved;
extension_marker->magic;
extension_marker = (struct _aarch64_ctx *)
((unsigned char *) extension_marker + extension_marker->size))
{
if (extension_marker->magic == FPSIMD_MAGIC)
{
struct fpsimd_context *ctx =
(struct fpsimd_context *) extension_marker;
int i;
for (i = 0; i < AARCH64_DWARF_NUMBER_V; i++)
{
_Unwind_Sword offset;
fs->regs.reg[AARCH64_DWARF_V0 + i].how = REG_SAVED_OFFSET;
/* sigcontext contains 32 128bit registers for V0 to
V31. The kernel will have saved the contents of the
V registers. We want to unwind the callee save D
registers. Each D register comprises the least
significant half of the corresponding V register. We
need to offset into the saved V register dependent on
our endianness to find the saved D register. */
offset = (_Unwind_Ptr) & (ctx->vregs[i]) - new_cfa;
/* The endianness adjustment code below expects that a
saved V register is 16 bytes. */
gcc_assert (sizeof (ctx->vregs[0]) == 16);
#if defined (__AARCH64EB__)
offset = offset + 8;
#endif
fs->regs.reg[AARCH64_DWARF_V0 + i].loc.offset = offset;
}
}
else
{
/* There is context provided that we do not recognize! */
}
}
fs->regs.reg[31].how = REG_SAVED_OFFSET;
fs->regs.reg[31].loc.offset = (_Unwind_Ptr) & (sc->sp) - new_cfa;
fs->signal_frame = 1;
fs->regs.reg[DWARF_ALT_FRAME_RETURN_COLUMN].how = REG_SAVED_VAL_OFFSET;
fs->regs.reg[DWARF_ALT_FRAME_RETURN_COLUMN].loc.offset =
(_Unwind_Ptr) (sc->pc) - new_cfa;
fs->retaddr_column = DWARF_ALT_FRAME_RETURN_COLUMN;
return _URC_NO_REASON;
}
#endif
|