1 /* Target-dependent code for NetBSD/mips.
3 Copyright (C) 2002, 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
5 Contributed by Wasabi Systems, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
30 #include "gdb_assert.h"
31 #include "gdb_string.h"
33 #include "nbsd-tdep.h"
34 #include "mipsnbsd-tdep.h"
35 #include "mips-tdep.h"
37 #include "solib-svr4.h"
39 /* Shorthand for some register numbers used below. */
40 #define MIPS_PC_REGNUM MIPS_EMBED_PC_REGNUM
41 #define MIPS_FP0_REGNUM MIPS_EMBED_FP0_REGNUM
42 #define MIPS_FSR_REGNUM MIPS_EMBED_FP0_REGNUM + 32
44 /* Core file support. */
46 /* Number of registers in `struct reg' from <machine/reg.h>. */
47 #define MIPSNBSD_NUM_GREGS 38
49 /* Number of registers in `struct fpreg' from <machine/reg.h>. */
50 #define MIPSNBSD_NUM_FPREGS 33
52 /* Supply register REGNUM from the buffer specified by FPREGS and LEN
53 in the floating-point register set REGSET to register cache
54 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
57 mipsnbsd_supply_fpregset (const struct regset
*regset
,
58 struct regcache
*regcache
,
59 int regnum
, const void *fpregs
, size_t len
)
61 size_t regsize
= mips_isa_regsize (get_regcache_arch (regcache
));
62 const char *regs
= fpregs
;
65 gdb_assert (len
>= MIPSNBSD_NUM_FPREGS
* regsize
);
67 for (i
= MIPS_FP0_REGNUM
; i
<= MIPS_FSR_REGNUM
; i
++)
69 if (regnum
== i
|| regnum
== -1)
70 regcache_raw_supply (regcache
, i
,
71 regs
+ (i
- MIPS_FP0_REGNUM
) * regsize
);
75 /* Supply register REGNUM from the buffer specified by GREGS and LEN
76 in the general-purpose register set REGSET to register cache
77 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
80 mipsnbsd_supply_gregset (const struct regset
*regset
,
81 struct regcache
*regcache
, int regnum
,
82 const void *gregs
, size_t len
)
84 size_t regsize
= mips_isa_regsize (get_regcache_arch (regcache
));
85 const char *regs
= gregs
;
88 gdb_assert (len
>= MIPSNBSD_NUM_GREGS
* regsize
);
90 for (i
= 0; i
<= MIPS_PC_REGNUM
; i
++)
92 if (regnum
== i
|| regnum
== -1)
93 regcache_raw_supply (regcache
, i
, regs
+ i
* regsize
);
96 if (len
>= (MIPSNBSD_NUM_GREGS
+ MIPSNBSD_NUM_FPREGS
) * regsize
)
98 regs
+= MIPSNBSD_NUM_GREGS
* regsize
;
99 len
-= MIPSNBSD_NUM_GREGS
* regsize
;
100 mipsnbsd_supply_fpregset (regset
, regcache
, regnum
, regs
, len
);
104 /* NetBSD/mips register sets. */
106 static struct regset mipsnbsd_gregset
=
109 mipsnbsd_supply_gregset
112 static struct regset mipsnbsd_fpregset
=
115 mipsnbsd_supply_fpregset
118 /* Return the appropriate register set for the core section identified
119 by SECT_NAME and SECT_SIZE. */
121 static const struct regset
*
122 mipsnbsd_regset_from_core_section (struct gdbarch
*gdbarch
,
123 const char *sect_name
, size_t sect_size
)
125 size_t regsize
= mips_isa_regsize (gdbarch
);
127 if (strcmp (sect_name
, ".reg") == 0
128 && sect_size
>= MIPSNBSD_NUM_GREGS
* regsize
)
129 return &mipsnbsd_gregset
;
131 if (strcmp (sect_name
, ".reg2") == 0
132 && sect_size
>= MIPSNBSD_NUM_FPREGS
* regsize
)
133 return &mipsnbsd_fpregset
;
139 /* Conveniently, GDB uses the same register numbering as the
140 ptrace register structure used by NetBSD/mips. */
143 mipsnbsd_supply_reg (struct regcache
*regcache
, const char *regs
, int regno
)
147 for (i
= 0; i
<= gdbarch_pc_regnum (current_gdbarch
); i
++)
149 if (regno
== i
|| regno
== -1)
151 if (gdbarch_cannot_fetch_register (current_gdbarch
, i
))
152 regcache_raw_supply (regcache
, i
, NULL
);
154 regcache_raw_supply (regcache
, i
,
155 regs
+ (i
* mips_isa_regsize (current_gdbarch
)));
161 mipsnbsd_fill_reg (const struct regcache
*regcache
, char *regs
, int regno
)
165 for (i
= 0; i
<= gdbarch_pc_regnum (current_gdbarch
); i
++)
166 if ((regno
== i
|| regno
== -1)
167 && ! gdbarch_cannot_store_register (current_gdbarch
, i
))
168 regcache_raw_collect (regcache
, i
,
169 regs
+ (i
* mips_isa_regsize (current_gdbarch
)));
173 mipsnbsd_supply_fpreg (struct regcache
*regcache
, const char *fpregs
, int regno
)
177 for (i
= gdbarch_fp0_regnum (current_gdbarch
);
178 i
<= mips_regnum (current_gdbarch
)->fp_implementation_revision
;
181 if (regno
== i
|| regno
== -1)
183 if (gdbarch_cannot_fetch_register (current_gdbarch
, i
))
184 regcache_raw_supply (regcache
, i
, NULL
);
186 regcache_raw_supply (regcache
, i
,
188 + ((i
- gdbarch_fp0_regnum (current_gdbarch
))
189 * mips_isa_regsize (current_gdbarch
)));
195 mipsnbsd_fill_fpreg (const struct regcache
*regcache
, char *fpregs
, int regno
)
199 for (i
= gdbarch_fp0_regnum (current_gdbarch
);
200 i
<= mips_regnum (current_gdbarch
)->fp_control_status
;
202 if ((regno
== i
|| regno
== -1)
203 && ! gdbarch_cannot_store_register (current_gdbarch
, i
))
204 regcache_raw_collect (regcache
, i
,
205 fpregs
+ ((i
- gdbarch_fp0_regnum
207 * mips_isa_regsize (current_gdbarch
)));
210 /* Under NetBSD/mips, signal handler invocations can be identified by the
211 designated code sequence that is used to return from a signal handler.
212 In particular, the return address of a signal handler points to the
213 following code sequence:
216 li v0, 295 # __sigreturn14
219 Each instruction has a unique encoding, so we simply attempt to match
220 the instruction the PC is pointing to with any of the above instructions.
221 If there is a hit, we know the offset to the start of the designated
222 sequence and can then check whether we really are executing in the
223 signal trampoline. If not, -1 is returned, otherwise the offset from the
224 start of the return sequence is returned. */
226 #define RETCODE_NWORDS 3
227 #define RETCODE_SIZE (RETCODE_NWORDS * 4)
229 static const unsigned char sigtramp_retcode_mipsel
[RETCODE_SIZE
] =
231 0x10, 0x00, 0xa4, 0x27, /* addu a0, sp, 16 */
232 0x27, 0x01, 0x02, 0x24, /* li v0, 295 */
233 0x0c, 0x00, 0x00, 0x00, /* syscall */
236 static const unsigned char sigtramp_retcode_mipseb
[RETCODE_SIZE
] =
238 0x27, 0xa4, 0x00, 0x10, /* addu a0, sp, 16 */
239 0x24, 0x02, 0x01, 0x27, /* li v0, 295 */
240 0x00, 0x00, 0x00, 0x0c, /* syscall */
244 mipsnbsd_sigtramp_offset (struct frame_info
*next_frame
)
246 CORE_ADDR pc
= frame_pc_unwind (next_frame
);
247 const char *retcode
= gdbarch_byte_order (current_gdbarch
)
248 == BFD_ENDIAN_BIG
? sigtramp_retcode_mipseb
:
249 sigtramp_retcode_mipsel
;
250 unsigned char ret
[RETCODE_SIZE
], w
[4];
254 if (!safe_frame_unwind_memory (next_frame
, pc
, w
, sizeof (w
)))
257 for (i
= 0; i
< RETCODE_NWORDS
; i
++)
259 if (memcmp (w
, retcode
+ (i
* 4), 4) == 0)
262 if (i
== RETCODE_NWORDS
)
268 if (!safe_frame_unwind_memory (next_frame
, pc
, ret
, sizeof (ret
)))
271 if (memcmp (ret
, retcode
, RETCODE_SIZE
) == 0)
277 /* Figure out where the longjmp will land. We expect that we have
278 just entered longjmp and haven't yet setup the stack frame, so the
279 args are still in the argument regs. MIPS_A0_REGNUM points at the
280 jmp_buf structure from which we extract the PC that we will land
281 at. The PC is copied into *pc. This routine returns true on
284 #define NBSD_MIPS_JB_PC (2 * 4)
285 #define NBSD_MIPS_JB_ELEMENT_SIZE mips_isa_regsize (current_gdbarch)
286 #define NBSD_MIPS_JB_OFFSET (NBSD_MIPS_JB_PC * \
287 NBSD_MIPS_JB_ELEMENT_SIZE)
290 mipsnbsd_get_longjmp_target (struct frame_info
*frame
, CORE_ADDR
*pc
)
295 buf
= alloca (NBSD_MIPS_JB_ELEMENT_SIZE
);
297 jb_addr
= get_frame_register_unsigned (frame
, MIPS_A0_REGNUM
);
299 if (target_read_memory (jb_addr
+ NBSD_MIPS_JB_OFFSET
, buf
,
300 NBSD_MIPS_JB_ELEMENT_SIZE
))
303 *pc
= extract_unsigned_integer (buf
, NBSD_MIPS_JB_ELEMENT_SIZE
);
309 mipsnbsd_cannot_fetch_register (int regno
)
311 return (regno
== MIPS_ZERO_REGNUM
312 || regno
== mips_regnum (current_gdbarch
)->fp_implementation_revision
);
316 mipsnbsd_cannot_store_register (int regno
)
318 return (regno
== MIPS_ZERO_REGNUM
319 || regno
== mips_regnum (current_gdbarch
)->fp_implementation_revision
);
322 /* Shared library support. */
324 /* NetBSD/mips uses a slightly different `struct link_map' than the
325 other NetBSD platforms. */
327 static struct link_map_offsets
*
328 mipsnbsd_ilp32_fetch_link_map_offsets (void)
330 static struct link_map_offsets lmo
;
331 static struct link_map_offsets
*lmp
= NULL
;
337 lmo
.r_version_offset
= 0;
338 lmo
.r_version_size
= 4;
339 lmo
.r_map_offset
= 4;
340 lmo
.r_ldsomap_offset
= -1;
342 /* Everything we need is in the first 24 bytes. */
343 lmo
.link_map_size
= 24;
344 lmo
.l_addr_offset
= 4;
345 lmo
.l_name_offset
= 8;
346 lmo
.l_ld_offset
= 12;
347 lmo
.l_next_offset
= 16;
348 lmo
.l_prev_offset
= 20;
354 static struct link_map_offsets
*
355 mipsnbsd_lp64_fetch_link_map_offsets (void)
357 static struct link_map_offsets lmo
;
358 static struct link_map_offsets
*lmp
= NULL
;
364 lmo
.r_version_offset
= 0;
365 lmo
.r_version_size
= 4;
366 lmo
.r_map_offset
= 8;
367 lmo
.r_ldsomap_offset
= -1;
369 /* Everything we need is in the first 40 bytes. */
370 lmo
.link_map_size
= 48;
371 lmo
.l_addr_offset
= 0;
372 lmo
.l_name_offset
= 16;
373 lmo
.l_ld_offset
= 24;
374 lmo
.l_next_offset
= 32;
375 lmo
.l_prev_offset
= 40;
383 mipsnbsd_init_abi (struct gdbarch_info info
,
384 struct gdbarch
*gdbarch
)
386 set_gdbarch_regset_from_core_section
387 (gdbarch
, mipsnbsd_regset_from_core_section
);
389 set_gdbarch_get_longjmp_target (gdbarch
, mipsnbsd_get_longjmp_target
);
391 set_gdbarch_cannot_fetch_register (gdbarch
, mipsnbsd_cannot_fetch_register
);
392 set_gdbarch_cannot_store_register (gdbarch
, mipsnbsd_cannot_store_register
);
394 set_gdbarch_software_single_step (gdbarch
, mips_software_single_step
);
396 /* NetBSD/mips has SVR4-style shared libraries. */
397 set_solib_svr4_fetch_link_map_offsets
398 (gdbarch
, (gdbarch_ptr_bit (gdbarch
) == 32 ?
399 mipsnbsd_ilp32_fetch_link_map_offsets
:
400 mipsnbsd_lp64_fetch_link_map_offsets
));
404 static enum gdb_osabi
405 mipsnbsd_core_osabi_sniffer (bfd
*abfd
)
407 if (strcmp (bfd_get_target (abfd
), "netbsd-core") == 0)
408 return GDB_OSABI_NETBSD_ELF
;
410 return GDB_OSABI_UNKNOWN
;
414 _initialize_mipsnbsd_tdep (void)
416 gdbarch_register_osabi (bfd_arch_mips
, 0, GDB_OSABI_NETBSD_ELF
,