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
|
/* DWARF2 EH unwinding support for PowerPC and PowerPC64 Linux.
Copyright (C) 2004 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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 2, or (at your
option) any later version.
GCC 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 GCC; see the file COPYING. If not, write to the
Free Software Foundation, 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
/* This file defines our own versions of various kernel and user
structs, so that system headers are not needed, which otherwise
can make bootstrapping a new toolchain difficult. Do not use
these structs elsewhere; Many fields are missing, particularly
from the end of the structures. */
struct gcc_pt_regs
{
unsigned long gpr[32];
unsigned long nip;
unsigned long msr;
unsigned long orig_gpr3;
unsigned long ctr;
unsigned long link;
};
struct gcc_sigcontext
{
unsigned long pad[7];
struct gcc_pt_regs *regs;
};
struct gcc_ucontext
{
#ifdef __powerpc64__
unsigned long pad[21];
#else
unsigned long pad[5];
#endif
struct gcc_sigcontext uc_mcontext;
};
#ifdef __powerpc64__
enum { SIGNAL_FRAMESIZE = 128 };
/* If the current unwind info (FS) does not contain explicit info
saving R2, then we have to do a minor amount of code reading to
figure out if it was saved. The big problem here is that the
code that does the save/restore is generated by the linker, so
we have no good way to determine at compile time what to do. */
#define MD_FROB_UPDATE_CONTEXT frob_update_context
static void
frob_update_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
{
if (fs->regs.reg[2].how == REG_UNSAVED)
{
unsigned int *insn
= (unsigned int *) _Unwind_GetGR (context, LINK_REGISTER_REGNUM);
if (*insn == 0xE8410028)
_Unwind_SetGRPtr (context, 2, context->cfa + 40);
}
}
/* If PC is at a sigreturn trampoline, return a pointer to the
sigcontext. Otherwise return NULL. */
static struct gcc_sigcontext *
get_sigcontext (struct _Unwind_Context *context)
{
const unsigned char *pc = context->ra;
/* addi r1, r1, 128; li r0, 0x0077; sc (sigreturn) */
/* addi r1, r1, 128; li r0, 0x00AC; sc (rt_sigreturn) */
if (*(unsigned int *) (pc+0) != 0x38210000 + SIGNAL_FRAMESIZE
|| *(unsigned int *) (pc+8) != 0x44000002)
return NULL;
if (*(unsigned int *) (pc+4) == 0x38000077)
{
struct sigframe {
char gap[SIGNAL_FRAMESIZE];
struct gcc_sigcontext sigctx;
} *rt_ = context->cfa;
return &rt_->sigctx;
}
else if (*(unsigned int *) (pc+4) == 0x380000AC)
{
struct rt_sigframe {
int tramp[6];
void *pinfo;
struct gcc_ucontext *puc;
} *rt_ = (struct rt_sigframe *) pc;
return &rt_->puc->uc_mcontext;
}
return NULL;
}
#else /* !__powerpc64__ */
enum { SIGNAL_FRAMESIZE = 64 };
static struct gcc_sigcontext *
get_sigcontext (struct _Unwind_Context *context)
{
const unsigned char *pc = context->ra;
/* li r0, 0x7777; sc (sigreturn old) */
/* li r0, 0x0077; sc (sigreturn new) */
/* li r0, 0x6666; sc (rt_sigreturn old) */
/* li r0, 0x00AC; sc (rt_sigreturn new) */
if (*(unsigned int *) (pc+4) != 0x44000002)
return NULL;
if (*(unsigned int *) (pc+0) == 0x38007777
|| *(unsigned int *) (pc+0) == 0x38000077)
{
struct sigframe {
char gap[SIGNAL_FRAMESIZE];
struct gcc_sigcontext sigctx;
} *rt_ = context->cfa;
return &rt_->sigctx;
}
else if (*(unsigned int *) (pc+0) == 0x38006666
|| *(unsigned int *) (pc+0) == 0x380000AC)
{
struct rt_sigframe {
char gap[SIGNAL_FRAMESIZE + 16];
char siginfo[128];
struct gcc_ucontext uc;
} *rt_ = context->cfa;
return &rt_->uc.uc_mcontext;
}
return NULL;
}
#endif
/* Do code reading to identify a signal frame, and set the frame
state data appropriately. See unwind-dw2.c for the structs. */
#define MD_FALLBACK_FRAME_STATE_FOR ppc_fallback_frame_state
static _Unwind_Reason_Code
ppc_fallback_frame_state (struct _Unwind_Context *context,
_Unwind_FrameState *fs)
{
struct gcc_sigcontext *sc = get_sigcontext (context);
long new_cfa;
int i;
if (sc == NULL)
return _URC_END_OF_STACK;
new_cfa = sc->regs->gpr[STACK_POINTER_REGNUM];
fs->cfa_how = CFA_REG_OFFSET;
fs->cfa_reg = STACK_POINTER_REGNUM;
fs->cfa_offset = new_cfa - (long) context->cfa;
for (i = 0; i < 32; i++)
if (i != STACK_POINTER_REGNUM)
{
fs->regs.reg[i].how = REG_SAVED_OFFSET;
fs->regs.reg[i].loc.offset
= (long)&(sc->regs->gpr[i]) - new_cfa;
}
fs->regs.reg[LINK_REGISTER_REGNUM].how = REG_SAVED_OFFSET;
fs->regs.reg[LINK_REGISTER_REGNUM].loc.offset
= (long)&(sc->regs->link) - new_cfa;
fs->regs.reg[ARG_POINTER_REGNUM].how = REG_SAVED_OFFSET;
fs->regs.reg[ARG_POINTER_REGNUM].loc.offset
= (long)&(sc->regs->nip) - new_cfa;
fs->retaddr_column = ARG_POINTER_REGNUM;
return _URC_NO_REASON;
}
|
