1 /* Target-dependent code for NetBSD/mips.
3 Copyright (C) 2002-2018 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 "nbsd-tdep.h"
31 #include "mips-nbsd-tdep.h"
32 #include "mips-tdep.h"
34 #include "solib-svr4.h"
36 /* Shorthand for some register numbers used below. */
37 #define MIPS_PC_REGNUM MIPS_EMBED_PC_REGNUM
38 #define MIPS_FP0_REGNUM MIPS_EMBED_FP0_REGNUM
39 #define MIPS_FSR_REGNUM MIPS_EMBED_FP0_REGNUM + 32
41 /* Core file support. */
43 /* Number of registers in `struct reg' from <machine/reg.h>. */
44 #define MIPSNBSD_NUM_GREGS 38
46 /* Number of registers in `struct fpreg' from <machine/reg.h>. */
47 #define MIPSNBSD_NUM_FPREGS 33
49 /* Supply register REGNUM from the buffer specified by FPREGS and LEN
50 in the floating-point register set REGSET to register cache
51 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
54 mipsnbsd_supply_fpregset (const struct regset
*regset
,
55 struct regcache
*regcache
,
56 int regnum
, const void *fpregs
, size_t len
)
58 size_t regsize
= mips_isa_regsize (regcache
->arch ());
59 const char *regs
= (const char *) fpregs
;
62 gdb_assert (len
>= MIPSNBSD_NUM_FPREGS
* regsize
);
64 for (i
= MIPS_FP0_REGNUM
; i
<= MIPS_FSR_REGNUM
; i
++)
66 if (regnum
== i
|| regnum
== -1)
67 regcache
->raw_supply (i
, regs
+ (i
- MIPS_FP0_REGNUM
) * regsize
);
71 /* Supply register REGNUM from the buffer specified by GREGS and LEN
72 in the general-purpose register set REGSET to register cache
73 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
76 mipsnbsd_supply_gregset (const struct regset
*regset
,
77 struct regcache
*regcache
, int regnum
,
78 const void *gregs
, size_t len
)
80 size_t regsize
= mips_isa_regsize (regcache
->arch ());
81 const char *regs
= (const char *) gregs
;
84 gdb_assert (len
>= MIPSNBSD_NUM_GREGS
* regsize
);
86 for (i
= 0; i
<= MIPS_PC_REGNUM
; i
++)
88 if (regnum
== i
|| regnum
== -1)
89 regcache
->raw_supply (i
, regs
+ i
* regsize
);
92 if (len
>= (MIPSNBSD_NUM_GREGS
+ MIPSNBSD_NUM_FPREGS
) * regsize
)
94 regs
+= MIPSNBSD_NUM_GREGS
* regsize
;
95 len
-= MIPSNBSD_NUM_GREGS
* regsize
;
96 mipsnbsd_supply_fpregset (regset
, regcache
, regnum
, regs
, len
);
100 /* NetBSD/mips register sets. */
102 static const struct regset mipsnbsd_gregset
=
105 mipsnbsd_supply_gregset
,
110 static const struct regset mipsnbsd_fpregset
=
113 mipsnbsd_supply_fpregset
116 /* Iterate over core file register note sections. */
119 mipsnbsd_iterate_over_regset_sections (struct gdbarch
*gdbarch
,
120 iterate_over_regset_sections_cb
*cb
,
122 const struct regcache
*regcache
)
124 size_t regsize
= mips_isa_regsize (gdbarch
);
126 cb (".reg", MIPSNBSD_NUM_GREGS
* regsize
, &mipsnbsd_gregset
,
128 cb (".reg2", MIPSNBSD_NUM_FPREGS
* regsize
, &mipsnbsd_fpregset
,
133 /* Conveniently, GDB uses the same register numbering as the
134 ptrace register structure used by NetBSD/mips. */
137 mipsnbsd_supply_reg (struct regcache
*regcache
, const char *regs
, int regno
)
139 struct gdbarch
*gdbarch
= regcache
->arch ();
142 for (i
= 0; i
<= gdbarch_pc_regnum (gdbarch
); i
++)
144 if (regno
== i
|| regno
== -1)
146 if (gdbarch_cannot_fetch_register (gdbarch
, i
))
147 regcache
->raw_supply (i
, NULL
);
150 (i
, regs
+ (i
* mips_isa_regsize (gdbarch
)));
156 mipsnbsd_fill_reg (const struct regcache
*regcache
, char *regs
, int regno
)
158 struct gdbarch
*gdbarch
= regcache
->arch ();
161 for (i
= 0; i
<= gdbarch_pc_regnum (gdbarch
); i
++)
162 if ((regno
== i
|| regno
== -1)
163 && ! gdbarch_cannot_store_register (gdbarch
, i
))
164 regcache_raw_collect (regcache
, i
,
165 regs
+ (i
* mips_isa_regsize (gdbarch
)));
169 mipsnbsd_supply_fpreg (struct regcache
*regcache
,
170 const char *fpregs
, int regno
)
172 struct gdbarch
*gdbarch
= regcache
->arch ();
175 for (i
= gdbarch_fp0_regnum (gdbarch
);
176 i
<= mips_regnum (gdbarch
)->fp_implementation_revision
;
179 if (regno
== i
|| regno
== -1)
181 if (gdbarch_cannot_fetch_register (gdbarch
, i
))
182 regcache
->raw_supply (i
, NULL
);
184 regcache
->raw_supply (i
,
186 + ((i
- gdbarch_fp0_regnum (gdbarch
))
187 * mips_isa_regsize (gdbarch
)));
193 mipsnbsd_fill_fpreg (const struct regcache
*regcache
, char *fpregs
, int regno
)
195 struct gdbarch
*gdbarch
= regcache
->arch ();
198 for (i
= gdbarch_fp0_regnum (gdbarch
);
199 i
<= mips_regnum (gdbarch
)->fp_control_status
;
201 if ((regno
== i
|| regno
== -1)
202 && ! gdbarch_cannot_store_register (gdbarch
, i
))
203 regcache_raw_collect (regcache
, i
,
204 fpregs
+ ((i
- gdbarch_fp0_regnum (gdbarch
))
205 * mips_isa_regsize (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 */
245 /* Figure out where the longjmp will land. We expect that we have
246 just entered longjmp and haven't yet setup the stack frame, so the
247 args are still in the argument regs. MIPS_A0_REGNUM points at the
248 jmp_buf structure from which we extract the PC that we will land
249 at. The PC is copied into *pc. This routine returns true on
252 #define NBSD_MIPS_JB_PC (2 * 4)
253 #define NBSD_MIPS_JB_ELEMENT_SIZE(gdbarch) mips_isa_regsize (gdbarch)
254 #define NBSD_MIPS_JB_OFFSET(gdbarch) (NBSD_MIPS_JB_PC * \
255 NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch))
258 mipsnbsd_get_longjmp_target (struct frame_info
*frame
, CORE_ADDR
*pc
)
260 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
261 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
265 buf
= (gdb_byte
*) alloca (NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
));
267 jb_addr
= get_frame_register_unsigned (frame
, MIPS_A0_REGNUM
);
269 if (target_read_memory (jb_addr
+ NBSD_MIPS_JB_OFFSET (gdbarch
), buf
,
270 NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
)))
273 *pc
= extract_unsigned_integer (buf
, NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
),
279 mipsnbsd_cannot_fetch_register (struct gdbarch
*gdbarch
, int regno
)
281 return (regno
== MIPS_ZERO_REGNUM
282 || regno
== mips_regnum (gdbarch
)->fp_implementation_revision
);
286 mipsnbsd_cannot_store_register (struct gdbarch
*gdbarch
, int regno
)
288 return (regno
== MIPS_ZERO_REGNUM
289 || regno
== mips_regnum (gdbarch
)->fp_implementation_revision
);
292 /* Shared library support. */
294 /* NetBSD/mips uses a slightly different `struct link_map' than the
295 other NetBSD platforms. */
297 static struct link_map_offsets
*
298 mipsnbsd_ilp32_fetch_link_map_offsets (void)
300 static struct link_map_offsets lmo
;
301 static struct link_map_offsets
*lmp
= NULL
;
307 lmo
.r_version_offset
= 0;
308 lmo
.r_version_size
= 4;
309 lmo
.r_map_offset
= 4;
310 lmo
.r_brk_offset
= 8;
311 lmo
.r_ldsomap_offset
= -1;
313 /* Everything we need is in the first 24 bytes. */
314 lmo
.link_map_size
= 24;
315 lmo
.l_addr_offset
= 4;
316 lmo
.l_name_offset
= 8;
317 lmo
.l_ld_offset
= 12;
318 lmo
.l_next_offset
= 16;
319 lmo
.l_prev_offset
= 20;
325 static struct link_map_offsets
*
326 mipsnbsd_lp64_fetch_link_map_offsets (void)
328 static struct link_map_offsets lmo
;
329 static struct link_map_offsets
*lmp
= NULL
;
335 lmo
.r_version_offset
= 0;
336 lmo
.r_version_size
= 4;
337 lmo
.r_map_offset
= 8;
338 lmo
.r_brk_offset
= 16;
339 lmo
.r_ldsomap_offset
= -1;
341 /* Everything we need is in the first 40 bytes. */
342 lmo
.link_map_size
= 48;
343 lmo
.l_addr_offset
= 0;
344 lmo
.l_name_offset
= 16;
345 lmo
.l_ld_offset
= 24;
346 lmo
.l_next_offset
= 32;
347 lmo
.l_prev_offset
= 40;
355 mipsnbsd_init_abi (struct gdbarch_info info
,
356 struct gdbarch
*gdbarch
)
358 set_gdbarch_iterate_over_regset_sections
359 (gdbarch
, mipsnbsd_iterate_over_regset_sections
);
361 set_gdbarch_get_longjmp_target (gdbarch
, mipsnbsd_get_longjmp_target
);
363 set_gdbarch_cannot_fetch_register (gdbarch
, mipsnbsd_cannot_fetch_register
);
364 set_gdbarch_cannot_store_register (gdbarch
, mipsnbsd_cannot_store_register
);
366 set_gdbarch_software_single_step (gdbarch
, mips_software_single_step
);
368 /* NetBSD/mips has SVR4-style shared libraries. */
369 set_solib_svr4_fetch_link_map_offsets
370 (gdbarch
, (gdbarch_ptr_bit (gdbarch
) == 32 ?
371 mipsnbsd_ilp32_fetch_link_map_offsets
:
372 mipsnbsd_lp64_fetch_link_map_offsets
));
376 _initialize_mipsnbsd_tdep (void)
378 gdbarch_register_osabi (bfd_arch_mips
, 0, GDB_OSABI_NETBSD
,