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
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
|
/* Target-dependent code for GNU/Linux running on the Fujitsu FR-V,
for GDB.
Copyright 2004 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 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "target.h"
#include "frame.h"
#include "osabi.h"
#include "elf-bfd.h"
#include "elf/frv.h"
#include "frv-tdep.h"
/* Define the size (in bytes) of an FR-V instruction. */
static const int frv_instr_size = 4;
enum {
NORMAL_SIGTRAMP = 1,
RT_SIGTRAMP = 2
};
static int
frv_linux_pc_in_sigtramp (CORE_ADDR pc, char *name)
{
char buf[frv_instr_size];
LONGEST instr;
int retval = 0;
if (target_read_memory (pc, buf, sizeof buf) != 0)
return 0;
instr = extract_unsigned_integer (buf, sizeof buf);
if (instr == 0x8efc0077) /* setlos #__NR_sigreturn, gr7 */
retval = NORMAL_SIGTRAMP;
else if (instr -= 0x8efc00ad) /* setlos #__NR_rt_sigreturn, gr7 */
retval = RT_SIGTRAMP;
else
return 0;
if (target_read_memory (pc + frv_instr_size, buf, sizeof buf) != 0)
return 0;
instr = extract_unsigned_integer (buf, sizeof buf);
if (instr != 0xc0700000) /* tira gr0, 0 */
return 0;
/* If we get this far, we'll return a non-zero value, either
NORMAL_SIGTRAMP (1) or RT_SIGTRAMP (2). */
return retval;
}
/* Given NEXT_FRAME, "callee" frame of the sigtramp frame that we
wish to decode, and REGNO, one of the frv register numbers defined
in frv-tdep.h, return the address of the saved register (corresponding
to REGNO) in the sigtramp frame. Return -1 if the register is not
found in the sigtramp frame. The magic numbers in the code below
were computed by examining the following kernel structs:
From arch/frvnommu/signal.c:
struct sigframe
{
void (*pretcode)(void);
int sig;
struct sigcontext sc;
unsigned long extramask[_NSIG_WORDS-1];
uint32_t retcode[2];
};
struct rt_sigframe
{
void (*pretcode)(void);
int sig;
struct siginfo *pinfo;
void *puc;
struct siginfo info;
struct ucontext uc;
uint32_t retcode[2];
};
From include/asm-frvnommu/ucontext.h:
struct ucontext {
unsigned long uc_flags;
struct ucontext *uc_link;
stack_t uc_stack;
struct sigcontext uc_mcontext;
sigset_t uc_sigmask;
};
From include/asm-frvnommu/sigcontext.h:
struct sigcontext {
struct user_context sc_context;
unsigned long sc_oldmask;
} __attribute__((aligned(8)));
From include/asm-frvnommu/registers.h:
struct user_int_regs
{
unsigned long psr;
unsigned long isr;
unsigned long ccr;
unsigned long cccr;
unsigned long lr;
unsigned long lcr;
unsigned long pc;
unsigned long __status;
unsigned long syscallno;
unsigned long orig_gr8;
unsigned long gner[2];
unsigned long long iacc[1];
union {
unsigned long tbr;
unsigned long gr[64];
};
};
struct user_fpmedia_regs
{
unsigned long fr[64];
unsigned long fner[2];
unsigned long msr[2];
unsigned long acc[8];
unsigned char accg[8];
unsigned long fsr[1];
};
struct user_context
{
struct user_int_regs i;
struct user_fpmedia_regs f;
void *extension;
} __attribute__((aligned(8))); */
static CORE_ADDR
frv_linux_sigcontext_reg_addr (struct frame_info *next_frame, int regno,
CORE_ADDR *sc_addr_cache_ptr)
{
CORE_ADDR sc_addr;
if (sc_addr_cache_ptr && *sc_addr_cache_ptr)
{
sc_addr = *sc_addr_cache_ptr;
}
else
{
CORE_ADDR pc, sp;
char buf[4];
int tramp_type;
pc = frame_pc_unwind (next_frame);
tramp_type = frv_linux_pc_in_sigtramp (pc, 0);
frame_unwind_register (next_frame, sp_regnum, buf);
sp = extract_unsigned_integer (buf, sizeof buf);
if (tramp_type == NORMAL_SIGTRAMP)
{
/* For a normal sigtramp frame, the sigcontext struct starts
at SP + 8. */
sc_addr = sp + 8;
}
else if (tramp_type == RT_SIGTRAMP)
{
/* For a realtime sigtramp frame, SP + 12 contains a pointer
to the a ucontext struct. The ucontext struct contains
a sigcontext struct starting 12 bytes in. */
if (target_read_memory (sp + 12, buf, sizeof buf) != 0)
{
warning ("Can't read realtime sigtramp frame.");
return 0;
}
sc_addr = extract_unsigned_integer (buf, sizeof buf);
sc_addr += 12;
}
else
internal_error (__FILE__, __LINE__, "not a signal trampoline");
if (sc_addr_cache_ptr)
*sc_addr_cache_ptr = sc_addr;
}
switch (regno)
{
case psr_regnum :
return sc_addr + 0;
/* sc_addr + 4 has "isr", the Integer Status Register. */
case ccr_regnum :
return sc_addr + 8;
case cccr_regnum :
return sc_addr + 12;
case lr_regnum :
return sc_addr + 16;
case lcr_regnum :
return sc_addr + 20;
case pc_regnum :
return sc_addr + 24;
/* sc_addr + 28 is __status, the exception status.
sc_addr + 32 is syscallno, the syscall number or -1.
sc_addr + 36 is orig_gr8, the original syscall arg #1.
sc_addr + 40 is gner[0].
sc_addr + 44 is gner[1]. */
case iacc0h_regnum :
return sc_addr + 48;
case iacc0l_regnum :
return sc_addr + 52;
default :
if (first_gpr_regnum <= regno && regno <= last_gpr_regnum)
return sc_addr + 56 + 4 * (regno - first_gpr_regnum);
else if (first_fpr_regnum <= regno && regno <= last_fpr_regnum)
return sc_addr + 312 + 4 * (regno - first_fpr_regnum);
else
return -1; /* not saved. */
}
}
static void
frv_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
/* When the FR-V Linux kernel calls a signal handler, the return
address points to a bit of code on the stack. This function is
used to identify this bit of code as a signal trampoline in order
to support backtracing through calls to signal handlers. */
set_gdbarch_deprecated_pc_in_sigtramp (gdbarch, frv_linux_pc_in_sigtramp);
frv_set_sigcontext_reg_addr (gdbarch, frv_linux_sigcontext_reg_addr);
}
static enum gdb_osabi
frv_linux_elf_osabi_sniffer (bfd *abfd)
{
int elf_flags;
elf_flags = elf_elfheader (abfd)->e_flags;
/* Assume GNU/Linux if using the FDPIC ABI. If/when another OS shows
up that uses this ABI, we'll need to start using .note sections
or some such. */
if (elf_flags & EF_FRV_FDPIC)
return GDB_OSABI_LINUX;
else
return GDB_OSABI_UNKNOWN;
}
/* Provide a prototype to silence -Wmissing-prototypes. */
void _initialize_frv_linux_tdep (void);
void
_initialize_frv_linux_tdep (void)
{
gdbarch_register_osabi (bfd_arch_frv, 0, GDB_OSABI_LINUX, frv_linux_init_abi);
gdbarch_register_osabi_sniffer (bfd_arch_frv,
bfd_target_elf_flavour,
frv_linux_elf_osabi_sniffer);
}
|
