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
|
/* GNU/Linux on TI C6x target support.
Copyright (C) 2011-2019 Free Software Foundation, Inc.
Contributed by Yao Qi <yao@codesourcery.com>
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 "solib.h"
#include "osabi.h"
#include "linux-tdep.h"
#include "tic6x-tdep.h"
#include "trad-frame.h"
#include "tramp-frame.h"
#include "elf-bfd.h"
#include "elf/tic6x.h"
/* The offset from rt_sigframe pointer to SP register. */
#define TIC6X_SP_RT_SIGFRAME 8
/* Size of struct siginfo info. */
#define TIC6X_SIGINFO_SIZE 128
/* Size of type stack_t, which contains three fields of type void*, int, and
size_t respectively. */
#define TIC6X_STACK_T_SIZE (3 * 4)
static const gdb_byte tic6x_bkpt_bnop_be[] = { 0x00, 0x00, 0xa1, 0x22 };
static const gdb_byte tic6x_bkpt_bnop_le[] = { 0x22, 0xa1, 0x00, 0x00 };
/* Return the offset of register REGNUM in struct sigcontext. Return 0 if no
such register in sigcontext. */
static unsigned int
tic6x_register_sigcontext_offset (unsigned int regnum, struct gdbarch *gdbarch)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
if (regnum == TIC6X_A4_REGNUM || regnum == TIC6X_A4_REGNUM + 2
|| regnum == TIC6X_A4_REGNUM + 4)
return 4 * (regnum - TIC6X_A4_REGNUM + 2); /* A4, A6, A8 */
else if (regnum == TIC6X_A5_REGNUM || regnum == TIC6X_A5_REGNUM + 2
|| regnum == TIC6X_A5_REGNUM + 4)
return 4 * (regnum - TIC6X_A5_REGNUM + 12); /* A5, A7, A9 */
else if (regnum == TIC6X_B4_REGNUM || regnum == TIC6X_B4_REGNUM + 2
|| regnum == TIC6X_B4_REGNUM + 4)
return 4 * (regnum - TIC6X_B4_REGNUM + 3); /* B4, B6, B8 */
else if (regnum == TIC6X_B5_REGNUM || regnum == TIC6X_B5_REGNUM + 2
|| regnum == TIC6X_B5_REGNUM + 4)
return 4 * (regnum - TIC6X_B5_REGNUM + 19); /* B5, B7, B9 */
else if (regnum < TIC6X_A4_REGNUM)
return 4 * (regnum - 0 + 8); /* A0 - A3 */
else if (regnum >= TIC6X_B0_REGNUM && regnum < TIC6X_B4_REGNUM)
return 4 * (regnum - TIC6X_B0_REGNUM + 15); /* B0 - B3 */
else if (regnum >= 34 && regnum < 34 + 32)
return 4 * (regnum - 34 + 23); /* A16 - A31, B16 - B31 */
else if (regnum == TIC6X_PC_REGNUM)
return 4 * (tdep->has_gp ? 55 : 23);
else if (regnum == TIC6X_SP_REGNUM)
return 4;
return 0;
}
/* Support unwinding frame in signal trampoline. We don't check sigreturn,
since it is not used in kernel. */
static void
tic6x_linux_rt_sigreturn_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);
CORE_ADDR sp = get_frame_register_unsigned (this_frame, TIC6X_SP_REGNUM);
/* The base of struct sigcontext is computed by examining the definition of
struct rt_sigframe in linux kernel source arch/c6x/kernel/signal.c. */
CORE_ADDR base = (sp + TIC6X_SP_RT_SIGFRAME
/* Pointer type *pinfo and *puc in struct rt_sigframe. */
+ 4 + 4
+ TIC6X_SIGINFO_SIZE
+ 4 + 4 /* uc_flags and *uc_link in struct ucontext. */
+ TIC6X_STACK_T_SIZE);
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
unsigned int reg_offset;
unsigned int i;
for (i = 0; i < 10; i++) /* A0 - A9 */
{
reg_offset = tic6x_register_sigcontext_offset (i, gdbarch);
gdb_assert (reg_offset != 0);
trad_frame_set_reg_addr (this_cache, i, base + reg_offset);
}
for (i = TIC6X_B0_REGNUM; i < TIC6X_B0_REGNUM + 10; i++) /* B0 - B9 */
{
reg_offset = tic6x_register_sigcontext_offset (i, gdbarch);
gdb_assert (reg_offset != 0);
trad_frame_set_reg_addr (this_cache, i, base + reg_offset);
}
if (tdep->has_gp)
for (i = 34; i < 34 + 32; i++) /* A16 - A31, B16 - B31 */
{
reg_offset = tic6x_register_sigcontext_offset (i, gdbarch);
gdb_assert (reg_offset != 0);
trad_frame_set_reg_addr (this_cache, i, base + reg_offset);
}
trad_frame_set_reg_addr (this_cache, TIC6X_PC_REGNUM,
base + tic6x_register_sigcontext_offset (TIC6X_PC_REGNUM,
gdbarch));
trad_frame_set_reg_addr (this_cache, TIC6X_SP_REGNUM,
base + tic6x_register_sigcontext_offset (TIC6X_SP_REGNUM,
gdbarch));
/* Save a frame ID. */
trad_frame_set_id (this_cache, frame_id_build (sp, func));
}
static struct tramp_frame tic6x_linux_rt_sigreturn_tramp_frame =
{
SIGTRAMP_FRAME,
4,
{
{0x000045aa, 0x0fffffff}, /* mvk .S2 139,b0 */
{0x10000000, ULONGEST_MAX}, /* swe */
{TRAMP_SENTINEL_INSN}
},
tic6x_linux_rt_sigreturn_init
};
/* When FRAME is at a syscall instruction, return the PC of the next
instruction to be executed. */
static CORE_ADDR
tic6x_linux_syscall_next_pc (struct frame_info *frame)
{
ULONGEST syscall_number = get_frame_register_unsigned (frame,
TIC6X_B0_REGNUM);
CORE_ADDR pc = get_frame_pc (frame);
if (syscall_number == 139 /* rt_sigreturn */)
return frame_unwind_caller_pc (frame);
return pc + 4;
}
extern struct target_so_ops dsbt_so_ops;
static void
tic6x_uclinux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
linux_init_abi (info, gdbarch);
/* Shared library handling. */
set_solib_ops (gdbarch, &dsbt_so_ops);
tdep->syscall_next_pc = tic6x_linux_syscall_next_pc;
#ifdef HAVE_ELF
/* In tic6x Linux kernel, breakpoint instructions varies on different archs.
On C64x+ and C67x+, breakpoint instruction is 0x56454314, which is an
illegal opcode. On other arch, breakpoint instruction is 0x0000a122
(BNOP .S2 0,5). */
if (info.abfd)
switch (bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_PROC, Tag_ISA))
{
case C6XABI_Tag_ISA_C64XP:
case C6XABI_Tag_ISA_C67XP:
if (info.byte_order == BFD_ENDIAN_BIG)
tdep->breakpoint = tic6x_bkpt_illegal_opcode_be;
else
tdep->breakpoint = tic6x_bkpt_illegal_opcode_le;
break;
default:
{
if (info.byte_order == BFD_ENDIAN_BIG)
tdep->breakpoint = tic6x_bkpt_bnop_be;
else
tdep->breakpoint = tic6x_bkpt_bnop_le;
}
}
#endif
/* Signal trampoline support. */
tramp_frame_prepend_unwinder (gdbarch,
&tic6x_linux_rt_sigreturn_tramp_frame);
}
void
_initialize_tic6x_linux_tdep (void)
{
gdbarch_register_osabi (bfd_arch_tic6x, 0, GDB_OSABI_LINUX,
tic6x_uclinux_init_abi);
}
|
