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
<= gdbarch_pc_regnum (current_gdbarch
); 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
<= gdbarch_pc_regnum (current_gdbarch
); 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
)
179 for (i
= gdbarch_fp0_regnum (current_gdbarch
);
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
,
190 + ((i
- gdbarch_fp0_regnum (current_gdbarch
))
191 * mips_isa_regsize (current_gdbarch
)));
197 mipsnbsd_fill_fpreg (const struct regcache
*regcache
, char *fpregs
, int regno
)
201 for (i
= gdbarch_fp0_regnum (current_gdbarch
);
202 i
<= mips_regnum (current_gdbarch
)->fp_control_status
;
204 if ((regno
== i
|| regno
== -1)
205 && ! gdbarch_cannot_store_register (current_gdbarch
, i
))
206 regcache_raw_collect (regcache
, i
,
207 fpregs
+ ((i
- gdbarch_fp0_regnum
209 * mips_isa_regsize (current_gdbarch
)));
212 /* Under NetBSD/mips, signal handler invocations can be identified by the
213 designated code sequence that is used to return from a signal handler.
214 In particular, the return address of a signal handler points to the
215 following code sequence:
218 li v0, 295 # __sigreturn14
221 Each instruction has a unique encoding, so we simply attempt to match
222 the instruction the PC is pointing to with any of the above instructions.
223 If there is a hit, we know the offset to the start of the designated
224 sequence and can then check whether we really are executing in the
225 signal trampoline. If not, -1 is returned, otherwise the offset from the
226 start of the return sequence is returned. */
228 #define RETCODE_NWORDS 3
229 #define RETCODE_SIZE (RETCODE_NWORDS * 4)
231 static const unsigned char sigtramp_retcode_mipsel
[RETCODE_SIZE
] =
233 0x10, 0x00, 0xa4, 0x27, /* addu a0, sp, 16 */
234 0x27, 0x01, 0x02, 0x24, /* li v0, 295 */
235 0x0c, 0x00, 0x00, 0x00, /* syscall */
238 static const unsigned char sigtramp_retcode_mipseb
[RETCODE_SIZE
] =
240 0x27, 0xa4, 0x00, 0x10, /* addu a0, sp, 16 */
241 0x24, 0x02, 0x01, 0x27, /* li v0, 295 */
242 0x00, 0x00, 0x00, 0x0c, /* syscall */
246 mipsnbsd_sigtramp_offset (struct frame_info
*next_frame
)
248 CORE_ADDR pc
= frame_pc_unwind (next_frame
);
249 const char *retcode
= gdbarch_byte_order (current_gdbarch
)
250 == BFD_ENDIAN_BIG
? sigtramp_retcode_mipseb
:
251 sigtramp_retcode_mipsel
;
252 unsigned char ret
[RETCODE_SIZE
], w
[4];
256 if (!safe_frame_unwind_memory (next_frame
, pc
, w
, sizeof (w
)))
259 for (i
= 0; i
< RETCODE_NWORDS
; i
++)
261 if (memcmp (w
, retcode
+ (i
* 4), 4) == 0)
264 if (i
== RETCODE_NWORDS
)
270 if (!safe_frame_unwind_memory (next_frame
, pc
, ret
, sizeof (ret
)))
273 if (memcmp (ret
, retcode
, RETCODE_SIZE
) == 0)
279 /* Figure out where the longjmp will land. We expect that we have
280 just entered longjmp and haven't yet setup the stack frame, so the
281 args are still in the argument regs. MIPS_A0_REGNUM points at the
282 jmp_buf structure from which we extract the PC that we will land
283 at. The PC is copied into *pc. This routine returns true on
286 #define NBSD_MIPS_JB_PC (2 * 4)
287 #define NBSD_MIPS_JB_ELEMENT_SIZE mips_isa_regsize (current_gdbarch)
288 #define NBSD_MIPS_JB_OFFSET (NBSD_MIPS_JB_PC * \
289 NBSD_MIPS_JB_ELEMENT_SIZE)
292 mipsnbsd_get_longjmp_target (struct frame_info
*frame
, CORE_ADDR
*pc
)
297 buf
= alloca (NBSD_MIPS_JB_ELEMENT_SIZE
);
299 jb_addr
= get_frame_register_unsigned (frame
, MIPS_A0_REGNUM
);
301 if (target_read_memory (jb_addr
+ NBSD_MIPS_JB_OFFSET
, buf
,
302 NBSD_MIPS_JB_ELEMENT_SIZE
))
305 *pc
= extract_unsigned_integer (buf
, NBSD_MIPS_JB_ELEMENT_SIZE
);
311 mipsnbsd_cannot_fetch_register (int regno
)
313 return (regno
== MIPS_ZERO_REGNUM
314 || regno
== mips_regnum (current_gdbarch
)->fp_implementation_revision
);
318 mipsnbsd_cannot_store_register (int regno
)
320 return (regno
== MIPS_ZERO_REGNUM
321 || regno
== mips_regnum (current_gdbarch
)->fp_implementation_revision
);
324 /* Shared library support. */
326 /* NetBSD/mips uses a slightly different `struct link_map' than the
327 other NetBSD platforms. */
329 static struct link_map_offsets
*
330 mipsnbsd_ilp32_fetch_link_map_offsets (void)
332 static struct link_map_offsets lmo
;
333 static struct link_map_offsets
*lmp
= NULL
;
339 lmo
.r_version_offset
= 0;
340 lmo
.r_version_size
= 4;
341 lmo
.r_map_offset
= 4;
342 lmo
.r_ldsomap_offset
= -1;
344 /* Everything we need is in the first 24 bytes. */
345 lmo
.link_map_size
= 24;
346 lmo
.l_addr_offset
= 4;
347 lmo
.l_name_offset
= 8;
348 lmo
.l_ld_offset
= 12;
349 lmo
.l_next_offset
= 16;
350 lmo
.l_prev_offset
= 20;
356 static struct link_map_offsets
*
357 mipsnbsd_lp64_fetch_link_map_offsets (void)
359 static struct link_map_offsets lmo
;
360 static struct link_map_offsets
*lmp
= NULL
;
366 lmo
.r_version_offset
= 0;
367 lmo
.r_version_size
= 4;
368 lmo
.r_map_offset
= 8;
369 lmo
.r_ldsomap_offset
= -1;
371 /* Everything we need is in the first 40 bytes. */
372 lmo
.link_map_size
= 48;
373 lmo
.l_addr_offset
= 0;
374 lmo
.l_name_offset
= 16;
375 lmo
.l_ld_offset
= 24;
376 lmo
.l_next_offset
= 32;
377 lmo
.l_prev_offset
= 40;
385 mipsnbsd_init_abi (struct gdbarch_info info
,
386 struct gdbarch
*gdbarch
)
388 set_gdbarch_regset_from_core_section
389 (gdbarch
, mipsnbsd_regset_from_core_section
);
391 set_gdbarch_get_longjmp_target (gdbarch
, mipsnbsd_get_longjmp_target
);
393 set_gdbarch_cannot_fetch_register (gdbarch
, mipsnbsd_cannot_fetch_register
);
394 set_gdbarch_cannot_store_register (gdbarch
, mipsnbsd_cannot_store_register
);
396 set_gdbarch_software_single_step (gdbarch
, mips_software_single_step
);
398 /* NetBSD/mips has SVR4-style shared libraries. */
399 set_solib_svr4_fetch_link_map_offsets
400 (gdbarch
, (gdbarch_ptr_bit (gdbarch
) == 32 ?
401 mipsnbsd_ilp32_fetch_link_map_offsets
:
402 mipsnbsd_lp64_fetch_link_map_offsets
));
406 static enum gdb_osabi
407 mipsnbsd_core_osabi_sniffer (bfd
*abfd
)
409 if (strcmp (bfd_get_target (abfd
), "netbsd-core") == 0)
410 return GDB_OSABI_NETBSD_ELF
;
412 return GDB_OSABI_UNKNOWN
;
416 _initialize_mipsnbsd_tdep (void)
418 gdbarch_register_osabi (bfd_arch_mips
, 0, GDB_OSABI_NETBSD_ELF
,