1 /* Target-dependent code for NetBSD/mips.
3 Copyright (C) 2002-2014 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"
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 const struct regset mipsnbsd_gregset
=
109 mipsnbsd_supply_gregset
112 static const 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
)
145 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
148 for (i
= 0; i
<= gdbarch_pc_regnum (gdbarch
); i
++)
150 if (regno
== i
|| regno
== -1)
152 if (gdbarch_cannot_fetch_register (gdbarch
, i
))
153 regcache_raw_supply (regcache
, i
, NULL
);
155 regcache_raw_supply (regcache
, i
,
156 regs
+ (i
* mips_isa_regsize (gdbarch
)));
162 mipsnbsd_fill_reg (const struct regcache
*regcache
, char *regs
, int regno
)
164 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
167 for (i
= 0; i
<= gdbarch_pc_regnum (gdbarch
); i
++)
168 if ((regno
== i
|| regno
== -1)
169 && ! gdbarch_cannot_store_register (gdbarch
, i
))
170 regcache_raw_collect (regcache
, i
,
171 regs
+ (i
* mips_isa_regsize (gdbarch
)));
175 mipsnbsd_supply_fpreg (struct regcache
*regcache
,
176 const char *fpregs
, int regno
)
178 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
181 for (i
= gdbarch_fp0_regnum (gdbarch
);
182 i
<= mips_regnum (gdbarch
)->fp_implementation_revision
;
185 if (regno
== i
|| regno
== -1)
187 if (gdbarch_cannot_fetch_register (gdbarch
, i
))
188 regcache_raw_supply (regcache
, i
, NULL
);
190 regcache_raw_supply (regcache
, i
,
192 + ((i
- gdbarch_fp0_regnum (gdbarch
))
193 * mips_isa_regsize (gdbarch
)));
199 mipsnbsd_fill_fpreg (const struct regcache
*regcache
, char *fpregs
, int regno
)
201 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
204 for (i
= gdbarch_fp0_regnum (gdbarch
);
205 i
<= mips_regnum (gdbarch
)->fp_control_status
;
207 if ((regno
== i
|| regno
== -1)
208 && ! gdbarch_cannot_store_register (gdbarch
, i
))
209 regcache_raw_collect (regcache
, i
,
210 fpregs
+ ((i
- gdbarch_fp0_regnum (gdbarch
))
211 * mips_isa_regsize (gdbarch
)));
216 /* Under NetBSD/mips, signal handler invocations can be identified by the
217 designated code sequence that is used to return from a signal handler.
218 In particular, the return address of a signal handler points to the
219 following code sequence:
222 li v0, 295 # __sigreturn14
225 Each instruction has a unique encoding, so we simply attempt to match
226 the instruction the PC is pointing to with any of the above instructions.
227 If there is a hit, we know the offset to the start of the designated
228 sequence and can then check whether we really are executing in the
229 signal trampoline. If not, -1 is returned, otherwise the offset from the
230 start of the return sequence is returned. */
232 #define RETCODE_NWORDS 3
233 #define RETCODE_SIZE (RETCODE_NWORDS * 4)
235 static const unsigned char sigtramp_retcode_mipsel
[RETCODE_SIZE
] =
237 0x10, 0x00, 0xa4, 0x27, /* addu a0, sp, 16 */
238 0x27, 0x01, 0x02, 0x24, /* li v0, 295 */
239 0x0c, 0x00, 0x00, 0x00, /* syscall */
242 static const unsigned char sigtramp_retcode_mipseb
[RETCODE_SIZE
] =
244 0x27, 0xa4, 0x00, 0x10, /* addu a0, sp, 16 */
245 0x24, 0x02, 0x01, 0x27, /* li v0, 295 */
246 0x00, 0x00, 0x00, 0x0c, /* syscall */
251 /* Figure out where the longjmp will land. We expect that we have
252 just entered longjmp and haven't yet setup the stack frame, so the
253 args are still in the argument regs. MIPS_A0_REGNUM points at the
254 jmp_buf structure from which we extract the PC that we will land
255 at. The PC is copied into *pc. This routine returns true on
258 #define NBSD_MIPS_JB_PC (2 * 4)
259 #define NBSD_MIPS_JB_ELEMENT_SIZE(gdbarch) mips_isa_regsize (gdbarch)
260 #define NBSD_MIPS_JB_OFFSET(gdbarch) (NBSD_MIPS_JB_PC * \
261 NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch))
264 mipsnbsd_get_longjmp_target (struct frame_info
*frame
, CORE_ADDR
*pc
)
266 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
267 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
271 buf
= alloca (NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
));
273 jb_addr
= get_frame_register_unsigned (frame
, MIPS_A0_REGNUM
);
275 if (target_read_memory (jb_addr
+ NBSD_MIPS_JB_OFFSET (gdbarch
), buf
,
276 NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
)))
279 *pc
= extract_unsigned_integer (buf
, NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
),
285 mipsnbsd_cannot_fetch_register (struct gdbarch
*gdbarch
, int regno
)
287 return (regno
== MIPS_ZERO_REGNUM
288 || regno
== mips_regnum (gdbarch
)->fp_implementation_revision
);
292 mipsnbsd_cannot_store_register (struct gdbarch
*gdbarch
, int regno
)
294 return (regno
== MIPS_ZERO_REGNUM
295 || regno
== mips_regnum (gdbarch
)->fp_implementation_revision
);
298 /* Shared library support. */
300 /* NetBSD/mips uses a slightly different `struct link_map' than the
301 other NetBSD platforms. */
303 static struct link_map_offsets
*
304 mipsnbsd_ilp32_fetch_link_map_offsets (void)
306 static struct link_map_offsets lmo
;
307 static struct link_map_offsets
*lmp
= NULL
;
313 lmo
.r_version_offset
= 0;
314 lmo
.r_version_size
= 4;
315 lmo
.r_map_offset
= 4;
316 lmo
.r_brk_offset
= 8;
317 lmo
.r_ldsomap_offset
= -1;
319 /* Everything we need is in the first 24 bytes. */
320 lmo
.link_map_size
= 24;
321 lmo
.l_addr_offset
= 4;
322 lmo
.l_name_offset
= 8;
323 lmo
.l_ld_offset
= 12;
324 lmo
.l_next_offset
= 16;
325 lmo
.l_prev_offset
= 20;
331 static struct link_map_offsets
*
332 mipsnbsd_lp64_fetch_link_map_offsets (void)
334 static struct link_map_offsets lmo
;
335 static struct link_map_offsets
*lmp
= NULL
;
341 lmo
.r_version_offset
= 0;
342 lmo
.r_version_size
= 4;
343 lmo
.r_map_offset
= 8;
344 lmo
.r_brk_offset
= 16;
345 lmo
.r_ldsomap_offset
= -1;
347 /* Everything we need is in the first 40 bytes. */
348 lmo
.link_map_size
= 48;
349 lmo
.l_addr_offset
= 0;
350 lmo
.l_name_offset
= 16;
351 lmo
.l_ld_offset
= 24;
352 lmo
.l_next_offset
= 32;
353 lmo
.l_prev_offset
= 40;
361 mipsnbsd_init_abi (struct gdbarch_info info
,
362 struct gdbarch
*gdbarch
)
364 set_gdbarch_regset_from_core_section
365 (gdbarch
, mipsnbsd_regset_from_core_section
);
367 set_gdbarch_get_longjmp_target (gdbarch
, mipsnbsd_get_longjmp_target
);
369 set_gdbarch_cannot_fetch_register (gdbarch
, mipsnbsd_cannot_fetch_register
);
370 set_gdbarch_cannot_store_register (gdbarch
, mipsnbsd_cannot_store_register
);
372 set_gdbarch_software_single_step (gdbarch
, mips_software_single_step
);
374 /* NetBSD/mips has SVR4-style shared libraries. */
375 set_solib_svr4_fetch_link_map_offsets
376 (gdbarch
, (gdbarch_ptr_bit (gdbarch
) == 32 ?
377 mipsnbsd_ilp32_fetch_link_map_offsets
:
378 mipsnbsd_lp64_fetch_link_map_offsets
));
382 /* Provide a prototype to silence -Wmissing-prototypes. */
383 extern initialize_file_ftype _initialize_mipsnbsd_tdep
;
386 _initialize_mipsnbsd_tdep (void)
388 gdbarch_register_osabi (bfd_arch_mips
, 0, GDB_OSABI_NETBSD_ELF
,