1 /* Target-dependent code for NetBSD/mips.
3 Copyright (C) 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
6 Contributed by Wasabi Systems, Inc.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>. */
31 #include "gdb_assert.h"
32 #include "gdb_string.h"
34 #include "nbsd-tdep.h"
35 #include "mipsnbsd-tdep.h"
36 #include "mips-tdep.h"
38 #include "solib-svr4.h"
40 /* Shorthand for some register numbers used below. */
41 #define MIPS_PC_REGNUM MIPS_EMBED_PC_REGNUM
42 #define MIPS_FP0_REGNUM MIPS_EMBED_FP0_REGNUM
43 #define MIPS_FSR_REGNUM MIPS_EMBED_FP0_REGNUM + 32
45 /* Core file support. */
47 /* Number of registers in `struct reg' from <machine/reg.h>. */
48 #define MIPSNBSD_NUM_GREGS 38
50 /* Number of registers in `struct fpreg' from <machine/reg.h>. */
51 #define MIPSNBSD_NUM_FPREGS 33
53 /* Supply register REGNUM from the buffer specified by FPREGS and LEN
54 in the floating-point register set REGSET to register cache
55 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
58 mipsnbsd_supply_fpregset (const struct regset
*regset
,
59 struct regcache
*regcache
,
60 int regnum
, const void *fpregs
, size_t len
)
62 size_t regsize
= mips_isa_regsize (get_regcache_arch (regcache
));
63 const char *regs
= fpregs
;
66 gdb_assert (len
>= MIPSNBSD_NUM_FPREGS
* regsize
);
68 for (i
= MIPS_FP0_REGNUM
; i
<= MIPS_FSR_REGNUM
; i
++)
70 if (regnum
== i
|| regnum
== -1)
71 regcache_raw_supply (regcache
, i
,
72 regs
+ (i
- MIPS_FP0_REGNUM
) * regsize
);
76 /* Supply register REGNUM from the buffer specified by GREGS and LEN
77 in the general-purpose register set REGSET to register cache
78 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
81 mipsnbsd_supply_gregset (const struct regset
*regset
,
82 struct regcache
*regcache
, int regnum
,
83 const void *gregs
, size_t len
)
85 size_t regsize
= mips_isa_regsize (get_regcache_arch (regcache
));
86 const char *regs
= gregs
;
89 gdb_assert (len
>= MIPSNBSD_NUM_GREGS
* regsize
);
91 for (i
= 0; i
<= MIPS_PC_REGNUM
; i
++)
93 if (regnum
== i
|| regnum
== -1)
94 regcache_raw_supply (regcache
, i
, regs
+ i
* regsize
);
97 if (len
>= (MIPSNBSD_NUM_GREGS
+ MIPSNBSD_NUM_FPREGS
) * regsize
)
99 regs
+= MIPSNBSD_NUM_GREGS
* regsize
;
100 len
-= MIPSNBSD_NUM_GREGS
* regsize
;
101 mipsnbsd_supply_fpregset (regset
, regcache
, regnum
, regs
, len
);
105 /* NetBSD/mips register sets. */
107 static struct regset mipsnbsd_gregset
=
110 mipsnbsd_supply_gregset
113 static struct regset mipsnbsd_fpregset
=
116 mipsnbsd_supply_fpregset
119 /* Return the appropriate register set for the core section identified
120 by SECT_NAME and SECT_SIZE. */
122 static const struct regset
*
123 mipsnbsd_regset_from_core_section (struct gdbarch
*gdbarch
,
124 const char *sect_name
, size_t sect_size
)
126 size_t regsize
= mips_isa_regsize (gdbarch
);
128 if (strcmp (sect_name
, ".reg") == 0
129 && sect_size
>= MIPSNBSD_NUM_GREGS
* regsize
)
130 return &mipsnbsd_gregset
;
132 if (strcmp (sect_name
, ".reg2") == 0
133 && sect_size
>= MIPSNBSD_NUM_FPREGS
* regsize
)
134 return &mipsnbsd_fpregset
;
140 /* Conveniently, GDB uses the same register numbering as the
141 ptrace register structure used by NetBSD/mips. */
144 mipsnbsd_supply_reg (struct regcache
*regcache
, const char *regs
, int regno
)
146 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
149 for (i
= 0; i
<= gdbarch_pc_regnum (gdbarch
); i
++)
151 if (regno
== i
|| regno
== -1)
153 if (gdbarch_cannot_fetch_register (gdbarch
, i
))
154 regcache_raw_supply (regcache
, i
, NULL
);
156 regcache_raw_supply (regcache
, i
,
157 regs
+ (i
* mips_isa_regsize (gdbarch
)));
163 mipsnbsd_fill_reg (const struct regcache
*regcache
, char *regs
, int regno
)
165 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
168 for (i
= 0; i
<= gdbarch_pc_regnum (gdbarch
); i
++)
169 if ((regno
== i
|| regno
== -1)
170 && ! gdbarch_cannot_store_register (gdbarch
, i
))
171 regcache_raw_collect (regcache
, i
,
172 regs
+ (i
* mips_isa_regsize (gdbarch
)));
176 mipsnbsd_supply_fpreg (struct regcache
*regcache
,
177 const char *fpregs
, int regno
)
179 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
182 for (i
= gdbarch_fp0_regnum (gdbarch
);
183 i
<= mips_regnum (gdbarch
)->fp_implementation_revision
;
186 if (regno
== i
|| regno
== -1)
188 if (gdbarch_cannot_fetch_register (gdbarch
, i
))
189 regcache_raw_supply (regcache
, i
, NULL
);
191 regcache_raw_supply (regcache
, i
,
193 + ((i
- gdbarch_fp0_regnum (gdbarch
))
194 * mips_isa_regsize (gdbarch
)));
200 mipsnbsd_fill_fpreg (const struct regcache
*regcache
, char *fpregs
, int regno
)
202 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
205 for (i
= gdbarch_fp0_regnum (gdbarch
);
206 i
<= mips_regnum (gdbarch
)->fp_control_status
;
208 if ((regno
== i
|| regno
== -1)
209 && ! gdbarch_cannot_store_register (gdbarch
, i
))
210 regcache_raw_collect (regcache
, i
,
211 fpregs
+ ((i
- gdbarch_fp0_regnum (gdbarch
))
212 * mips_isa_regsize (gdbarch
)));
215 /* Under NetBSD/mips, signal handler invocations can be identified by the
216 designated code sequence that is used to return from a signal handler.
217 In particular, the return address of a signal handler points to the
218 following code sequence:
221 li v0, 295 # __sigreturn14
224 Each instruction has a unique encoding, so we simply attempt to match
225 the instruction the PC is pointing to with any of the above instructions.
226 If there is a hit, we know the offset to the start of the designated
227 sequence and can then check whether we really are executing in the
228 signal trampoline. If not, -1 is returned, otherwise the offset from the
229 start of the return sequence is returned. */
231 #define RETCODE_NWORDS 3
232 #define RETCODE_SIZE (RETCODE_NWORDS * 4)
234 static const unsigned char sigtramp_retcode_mipsel
[RETCODE_SIZE
] =
236 0x10, 0x00, 0xa4, 0x27, /* addu a0, sp, 16 */
237 0x27, 0x01, 0x02, 0x24, /* li v0, 295 */
238 0x0c, 0x00, 0x00, 0x00, /* syscall */
241 static const unsigned char sigtramp_retcode_mipseb
[RETCODE_SIZE
] =
243 0x27, 0xa4, 0x00, 0x10, /* addu a0, sp, 16 */
244 0x24, 0x02, 0x01, 0x27, /* li v0, 295 */
245 0x00, 0x00, 0x00, 0x0c, /* syscall */
248 /* Figure out where the longjmp will land. We expect that we have
249 just entered longjmp and haven't yet setup the stack frame, so the
250 args are still in the argument regs. MIPS_A0_REGNUM points at the
251 jmp_buf structure from which we extract the PC that we will land
252 at. The PC is copied into *pc. This routine returns true on
255 #define NBSD_MIPS_JB_PC (2 * 4)
256 #define NBSD_MIPS_JB_ELEMENT_SIZE(gdbarch) mips_isa_regsize (gdbarch)
257 #define NBSD_MIPS_JB_OFFSET(gdbarch) (NBSD_MIPS_JB_PC * \
258 NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch))
261 mipsnbsd_get_longjmp_target (struct frame_info
*frame
, CORE_ADDR
*pc
)
263 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
264 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
268 buf
= alloca (NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
));
270 jb_addr
= get_frame_register_unsigned (frame
, MIPS_A0_REGNUM
);
272 if (target_read_memory (jb_addr
+ NBSD_MIPS_JB_OFFSET (gdbarch
), buf
,
273 NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
)))
276 *pc
= extract_unsigned_integer (buf
, NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch
),
282 mipsnbsd_cannot_fetch_register (struct gdbarch
*gdbarch
, int regno
)
284 return (regno
== MIPS_ZERO_REGNUM
285 || regno
== mips_regnum (gdbarch
)->fp_implementation_revision
);
289 mipsnbsd_cannot_store_register (struct gdbarch
*gdbarch
, int regno
)
291 return (regno
== MIPS_ZERO_REGNUM
292 || regno
== mips_regnum (gdbarch
)->fp_implementation_revision
);
295 /* Shared library support. */
297 /* NetBSD/mips uses a slightly different `struct link_map' than the
298 other NetBSD platforms. */
300 static struct link_map_offsets
*
301 mipsnbsd_ilp32_fetch_link_map_offsets (void)
303 static struct link_map_offsets lmo
;
304 static struct link_map_offsets
*lmp
= NULL
;
310 lmo
.r_version_offset
= 0;
311 lmo
.r_version_size
= 4;
312 lmo
.r_map_offset
= 4;
313 lmo
.r_brk_offset
= 8;
314 lmo
.r_ldsomap_offset
= -1;
316 /* Everything we need is in the first 24 bytes. */
317 lmo
.link_map_size
= 24;
318 lmo
.l_addr_offset
= 4;
319 lmo
.l_name_offset
= 8;
320 lmo
.l_ld_offset
= 12;
321 lmo
.l_next_offset
= 16;
322 lmo
.l_prev_offset
= 20;
328 static struct link_map_offsets
*
329 mipsnbsd_lp64_fetch_link_map_offsets (void)
331 static struct link_map_offsets lmo
;
332 static struct link_map_offsets
*lmp
= NULL
;
338 lmo
.r_version_offset
= 0;
339 lmo
.r_version_size
= 4;
340 lmo
.r_map_offset
= 8;
341 lmo
.r_brk_offset
= 16;
342 lmo
.r_ldsomap_offset
= -1;
344 /* Everything we need is in the first 40 bytes. */
345 lmo
.link_map_size
= 48;
346 lmo
.l_addr_offset
= 0;
347 lmo
.l_name_offset
= 16;
348 lmo
.l_ld_offset
= 24;
349 lmo
.l_next_offset
= 32;
350 lmo
.l_prev_offset
= 40;
358 mipsnbsd_init_abi (struct gdbarch_info info
,
359 struct gdbarch
*gdbarch
)
361 set_gdbarch_regset_from_core_section
362 (gdbarch
, mipsnbsd_regset_from_core_section
);
364 set_gdbarch_get_longjmp_target (gdbarch
, mipsnbsd_get_longjmp_target
);
366 set_gdbarch_cannot_fetch_register (gdbarch
, mipsnbsd_cannot_fetch_register
);
367 set_gdbarch_cannot_store_register (gdbarch
, mipsnbsd_cannot_store_register
);
369 set_gdbarch_software_single_step (gdbarch
, mips_software_single_step
);
371 /* NetBSD/mips has SVR4-style shared libraries. */
372 set_solib_svr4_fetch_link_map_offsets
373 (gdbarch
, (gdbarch_ptr_bit (gdbarch
) == 32 ?
374 mipsnbsd_ilp32_fetch_link_map_offsets
:
375 mipsnbsd_lp64_fetch_link_map_offsets
));
379 /* Provide a prototype to silence -Wmissing-prototypes. */
380 extern initialize_file_ftype _initialize_mipsnbsd_tdep
;
383 _initialize_mipsnbsd_tdep (void)
385 gdbarch_register_osabi (bfd_arch_mips
, 0, GDB_OSABI_NETBSD_ELF
,