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 2 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, write to the Free Software
21 Foundation, Inc., 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
32 #include "gdb_assert.h"
33 #include "gdb_string.h"
35 #include "nbsd-tdep.h"
36 #include "mipsnbsd-tdep.h"
37 #include "mips-tdep.h"
39 #include "solib-svr4.h"
41 /* Shorthand for some register numbers used below. */
42 #define MIPS_PC_REGNUM MIPS_EMBED_PC_REGNUM
43 #define MIPS_FP0_REGNUM MIPS_EMBED_FP0_REGNUM
44 #define MIPS_FSR_REGNUM MIPS_EMBED_FP0_REGNUM + 32
46 /* Core file support. */
48 /* Number of registers in `struct reg' from <machine/reg.h>. */
49 #define MIPSNBSD_NUM_GREGS 38
51 /* Number of registers in `struct fpreg' from <machine/reg.h>. */
52 #define MIPSNBSD_NUM_FPREGS 33
54 /* Supply register REGNUM from the buffer specified by FPREGS and LEN
55 in the floating-point register set REGSET to register cache
56 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
59 mipsnbsd_supply_fpregset (const struct regset
*regset
,
60 struct regcache
*regcache
,
61 int regnum
, const void *fpregs
, size_t len
)
63 size_t regsize
= mips_isa_regsize (get_regcache_arch (regcache
));
64 const char *regs
= fpregs
;
67 gdb_assert (len
>= MIPSNBSD_NUM_FPREGS
* regsize
);
69 for (i
= MIPS_FP0_REGNUM
; i
<= MIPS_FSR_REGNUM
; i
++)
71 if (regnum
== i
|| regnum
== -1)
72 regcache_raw_supply (regcache
, i
,
73 regs
+ (i
- MIPS_FP0_REGNUM
) * regsize
);
77 /* Supply register REGNUM from the buffer specified by GREGS and LEN
78 in the general-purpose register set REGSET to register cache
79 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
82 mipsnbsd_supply_gregset (const struct regset
*regset
,
83 struct regcache
*regcache
, int regnum
,
84 const void *gregs
, size_t len
)
86 size_t regsize
= mips_isa_regsize (get_regcache_arch (regcache
));
87 const char *regs
= gregs
;
90 gdb_assert (len
>= MIPSNBSD_NUM_GREGS
* regsize
);
92 for (i
= 0; i
<= MIPS_PC_REGNUM
; i
++)
94 if (regnum
== i
|| regnum
== -1)
95 regcache_raw_supply (regcache
, i
, regs
+ i
* regsize
);
98 if (len
>= (MIPSNBSD_NUM_GREGS
+ MIPSNBSD_NUM_FPREGS
) * regsize
)
100 regs
+= MIPSNBSD_NUM_GREGS
* regsize
;
101 len
-= MIPSNBSD_NUM_GREGS
* regsize
;
102 mipsnbsd_supply_fpregset (regset
, regcache
, regnum
, regs
, len
);
106 /* NetBSD/mips register sets. */
108 static struct regset mipsnbsd_gregset
=
111 mipsnbsd_supply_gregset
114 static struct regset mipsnbsd_fpregset
=
117 mipsnbsd_supply_fpregset
120 /* Return the appropriate register set for the core section identified
121 by SECT_NAME and SECT_SIZE. */
123 static const struct regset
*
124 mipsnbsd_regset_from_core_section (struct gdbarch
*gdbarch
,
125 const char *sect_name
, size_t sect_size
)
127 size_t regsize
= mips_isa_regsize (gdbarch
);
129 if (strcmp (sect_name
, ".reg") == 0
130 && sect_size
>= MIPSNBSD_NUM_GREGS
* regsize
)
131 return &mipsnbsd_gregset
;
133 if (strcmp (sect_name
, ".reg2") == 0
134 && sect_size
>= MIPSNBSD_NUM_FPREGS
* regsize
)
135 return &mipsnbsd_fpregset
;
141 /* Conveniently, GDB uses the same register numbering as the
142 ptrace register structure used by NetBSD/mips. */
145 mipsnbsd_supply_reg (struct regcache
*regcache
, const char *regs
, int regno
)
149 for (i
= 0; i
<= PC_REGNUM
; i
++)
151 if (regno
== i
|| regno
== -1)
153 if (gdbarch_cannot_fetch_register (current_gdbarch
, i
))
154 regcache_raw_supply (regcache
, i
, NULL
);
156 regcache_raw_supply (regcache
, i
,
157 regs
+ (i
* mips_isa_regsize (current_gdbarch
)));
163 mipsnbsd_fill_reg (const struct regcache
*regcache
, char *regs
, int regno
)
167 for (i
= 0; i
<= PC_REGNUM
; i
++)
168 if ((regno
== i
|| regno
== -1)
169 && ! gdbarch_cannot_store_register (current_gdbarch
, i
))
170 regcache_raw_collect (regcache
, i
,
171 regs
+ (i
* mips_isa_regsize (current_gdbarch
)));
175 mipsnbsd_supply_fpreg (struct regcache
*regcache
, const char *fpregs
, int regno
)
180 i
<= mips_regnum (current_gdbarch
)->fp_implementation_revision
;
183 if (regno
== i
|| regno
== -1)
185 if (gdbarch_cannot_fetch_register (current_gdbarch
, i
))
186 regcache_raw_supply (regcache
, i
, NULL
);
188 regcache_raw_supply (regcache
, i
,
189 fpregs
+ ((i
- FP0_REGNUM
) * mips_isa_regsize (current_gdbarch
)));
195 mipsnbsd_fill_fpreg (const struct regcache
*regcache
, char *fpregs
, int regno
)
199 for (i
= FP0_REGNUM
; i
<= mips_regnum (current_gdbarch
)->fp_control_status
;
201 if ((regno
== i
|| regno
== -1)
202 && ! gdbarch_cannot_store_register (current_gdbarch
, i
))
203 regcache_raw_collect (regcache
, i
,
204 fpregs
+ ((i
- FP0_REGNUM
) * mips_isa_regsize (current_gdbarch
)));
207 /* Under NetBSD/mips, signal handler invocations can be identified by the
208 designated code sequence that is used to return from a signal handler.
209 In particular, the return address of a signal handler points to the
210 following code sequence:
213 li v0, 295 # __sigreturn14
216 Each instruction has a unique encoding, so we simply attempt to match
217 the instruction the PC is pointing to with any of the above instructions.
218 If there is a hit, we know the offset to the start of the designated
219 sequence and can then check whether we really are executing in the
220 signal trampoline. If not, -1 is returned, otherwise the offset from the
221 start of the return sequence is returned. */
223 #define RETCODE_NWORDS 3
224 #define RETCODE_SIZE (RETCODE_NWORDS * 4)
226 static const unsigned char sigtramp_retcode_mipsel
[RETCODE_SIZE
] =
228 0x10, 0x00, 0xa4, 0x27, /* addu a0, sp, 16 */
229 0x27, 0x01, 0x02, 0x24, /* li v0, 295 */
230 0x0c, 0x00, 0x00, 0x00, /* syscall */
233 static const unsigned char sigtramp_retcode_mipseb
[RETCODE_SIZE
] =
235 0x27, 0xa4, 0x00, 0x10, /* addu a0, sp, 16 */
236 0x24, 0x02, 0x01, 0x27, /* li v0, 295 */
237 0x00, 0x00, 0x00, 0x0c, /* syscall */
241 mipsnbsd_sigtramp_offset (struct frame_info
*next_frame
)
243 CORE_ADDR pc
= frame_pc_unwind (next_frame
);
244 const char *retcode
= gdbarch_byte_order (current_gdbarch
)
245 == BFD_ENDIAN_BIG
? sigtramp_retcode_mipseb
:
246 sigtramp_retcode_mipsel
;
247 unsigned char ret
[RETCODE_SIZE
], w
[4];
251 if (!safe_frame_unwind_memory (next_frame
, pc
, w
, sizeof (w
)))
254 for (i
= 0; i
< RETCODE_NWORDS
; i
++)
256 if (memcmp (w
, retcode
+ (i
* 4), 4) == 0)
259 if (i
== RETCODE_NWORDS
)
265 if (!safe_frame_unwind_memory (next_frame
, pc
, ret
, sizeof (ret
)))
268 if (memcmp (ret
, retcode
, RETCODE_SIZE
) == 0)
274 /* Figure out where the longjmp will land. We expect that we have
275 just entered longjmp and haven't yet setup the stack frame, so the
276 args are still in the argument regs. MIPS_A0_REGNUM points at the
277 jmp_buf structure from which we extract the PC that we will land
278 at. The PC is copied into *pc. This routine returns true on
281 #define NBSD_MIPS_JB_PC (2 * 4)
282 #define NBSD_MIPS_JB_ELEMENT_SIZE mips_isa_regsize (current_gdbarch)
283 #define NBSD_MIPS_JB_OFFSET (NBSD_MIPS_JB_PC * \
284 NBSD_MIPS_JB_ELEMENT_SIZE)
287 mipsnbsd_get_longjmp_target (CORE_ADDR
*pc
)
292 buf
= alloca (NBSD_MIPS_JB_ELEMENT_SIZE
);
294 jb_addr
= read_register (MIPS_A0_REGNUM
);
296 if (target_read_memory (jb_addr
+ NBSD_MIPS_JB_OFFSET
, buf
,
297 NBSD_MIPS_JB_ELEMENT_SIZE
))
300 *pc
= extract_unsigned_integer (buf
, NBSD_MIPS_JB_ELEMENT_SIZE
);
306 mipsnbsd_cannot_fetch_register (int regno
)
308 return (regno
== MIPS_ZERO_REGNUM
309 || regno
== mips_regnum (current_gdbarch
)->fp_implementation_revision
);
313 mipsnbsd_cannot_store_register (int regno
)
315 return (regno
== MIPS_ZERO_REGNUM
316 || regno
== mips_regnum (current_gdbarch
)->fp_implementation_revision
);
319 /* Shared library support. */
321 /* NetBSD/mips uses a slightly different `struct link_map' than the
322 other NetBSD platforms. */
324 static struct link_map_offsets
*
325 mipsnbsd_ilp32_fetch_link_map_offsets (void)
327 static struct link_map_offsets lmo
;
328 static struct link_map_offsets
*lmp
= NULL
;
334 lmo
.r_version_offset
= 0;
335 lmo
.r_version_size
= 4;
336 lmo
.r_map_offset
= 4;
337 lmo
.r_ldsomap_offset
= -1;
339 /* Everything we need is in the first 24 bytes. */
340 lmo
.link_map_size
= 24;
341 lmo
.l_addr_offset
= 4;
342 lmo
.l_name_offset
= 8;
343 lmo
.l_ld_offset
= 12;
344 lmo
.l_next_offset
= 16;
345 lmo
.l_prev_offset
= 20;
351 static struct link_map_offsets
*
352 mipsnbsd_lp64_fetch_link_map_offsets (void)
354 static struct link_map_offsets lmo
;
355 static struct link_map_offsets
*lmp
= NULL
;
361 lmo
.r_version_offset
= 0;
362 lmo
.r_version_size
= 4;
363 lmo
.r_map_offset
= 8;
364 lmo
.r_ldsomap_offset
= -1;
366 /* Everything we need is in the first 40 bytes. */
367 lmo
.link_map_size
= 48;
368 lmo
.l_addr_offset
= 0;
369 lmo
.l_name_offset
= 16;
370 lmo
.l_ld_offset
= 24;
371 lmo
.l_next_offset
= 32;
372 lmo
.l_prev_offset
= 40;
380 mipsnbsd_init_abi (struct gdbarch_info info
,
381 struct gdbarch
*gdbarch
)
383 set_gdbarch_regset_from_core_section
384 (gdbarch
, mipsnbsd_regset_from_core_section
);
386 set_gdbarch_get_longjmp_target (gdbarch
, mipsnbsd_get_longjmp_target
);
388 set_gdbarch_cannot_fetch_register (gdbarch
, mipsnbsd_cannot_fetch_register
);
389 set_gdbarch_cannot_store_register (gdbarch
, mipsnbsd_cannot_store_register
);
391 set_gdbarch_software_single_step (gdbarch
, mips_software_single_step
);
393 /* NetBSD/mips has SVR4-style shared libraries. */
394 set_solib_svr4_fetch_link_map_offsets
395 (gdbarch
, (gdbarch_ptr_bit (gdbarch
) == 32 ?
396 mipsnbsd_ilp32_fetch_link_map_offsets
:
397 mipsnbsd_lp64_fetch_link_map_offsets
));
401 static enum gdb_osabi
402 mipsnbsd_core_osabi_sniffer (bfd
*abfd
)
404 if (strcmp (bfd_get_target (abfd
), "netbsd-core") == 0)
405 return GDB_OSABI_NETBSD_ELF
;
407 return GDB_OSABI_UNKNOWN
;
411 _initialize_mipsnbsd_tdep (void)
413 gdbarch_register_osabi (bfd_arch_mips
, 0, GDB_OSABI_NETBSD_ELF
,