1 /* Target-dependent code for NetBSD/alpha.
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 "alpha-tdep.h"
31 #include "alphabsd-tdep.h"
32 #include "nbsd-tdep.h"
33 #include "solib-svr4.h"
36 /* Core file support. */
38 /* Even though NetBSD/alpha used ELF since day one, it used the
39 traditional a.out-style core dump format before NetBSD 1.6. */
41 /* Sizeof `struct reg' in <machine/reg.h>. */
42 #define ALPHANBSD_SIZEOF_GREGS (32 * 8)
44 /* Sizeof `struct fpreg' in <machine/reg.h. */
45 #define ALPHANBSD_SIZEOF_FPREGS ((32 * 8) + 8)
47 /* Supply register REGNUM from the buffer specified by FPREGS and LEN
48 in the floating-point register set REGSET to register cache
49 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
52 alphanbsd_supply_fpregset (const struct regset
*regset
,
53 struct regcache
*regcache
,
54 int regnum
, const void *fpregs
, size_t len
)
56 const gdb_byte
*regs
= fpregs
;
59 gdb_assert (len
>= ALPHANBSD_SIZEOF_FPREGS
);
61 for (i
= ALPHA_FP0_REGNUM
; i
< ALPHA_FP0_REGNUM
+ 31; i
++)
63 if (regnum
== i
|| regnum
== -1)
64 regcache_raw_supply (regcache
, i
, regs
+ (i
- ALPHA_FP0_REGNUM
) * 8);
67 if (regnum
== ALPHA_FPCR_REGNUM
|| regnum
== -1)
68 regcache_raw_supply (regcache
, ALPHA_FPCR_REGNUM
, regs
+ 32 * 8);
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 alphanbsd_supply_gregset (const struct regset
*regset
,
77 struct regcache
*regcache
,
78 int regnum
, const void *gregs
, size_t len
)
80 const gdb_byte
*regs
= gregs
;
83 gdb_assert (len
>= ALPHANBSD_SIZEOF_GREGS
);
85 for (i
= 0; i
< ALPHA_ZERO_REGNUM
; i
++)
87 if (regnum
== i
|| regnum
== -1)
88 regcache_raw_supply (regcache
, i
, regs
+ i
* 8);
91 if (regnum
== ALPHA_PC_REGNUM
|| regnum
== -1)
92 regcache_raw_supply (regcache
, ALPHA_PC_REGNUM
, regs
+ 31 * 8);
95 /* Supply register REGNUM from the buffer specified by GREGS and LEN
96 in the general-purpose register set REGSET to register cache
97 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
100 alphanbsd_aout_supply_gregset (const struct regset
*regset
,
101 struct regcache
*regcache
,
102 int regnum
, const void *gregs
, size_t len
)
104 const gdb_byte
*regs
= gregs
;
107 /* Table to map a GDB register number to a trapframe register index. */
108 static const int regmap
[] =
120 gdb_assert (len
>= ALPHANBSD_SIZEOF_GREGS
);
122 for (i
= 0; i
< ARRAY_SIZE(regmap
); i
++)
124 if (regnum
== i
|| regnum
== -1)
125 regcache_raw_supply (regcache
, i
, regs
+ regmap
[i
] * 8);
128 if (regnum
== ALPHA_PC_REGNUM
|| regnum
== -1)
129 regcache_raw_supply (regcache
, ALPHA_PC_REGNUM
, regs
+ 31 * 8);
131 if (len
>= ALPHANBSD_SIZEOF_GREGS
+ ALPHANBSD_SIZEOF_FPREGS
)
133 regs
+= ALPHANBSD_SIZEOF_GREGS
;
134 len
-= ALPHANBSD_SIZEOF_GREGS
;
135 alphanbsd_supply_fpregset (regset
, regcache
, regnum
, regs
, len
);
139 /* NetBSD/alpha register sets. */
141 static const struct regset alphanbsd_gregset
=
144 alphanbsd_supply_gregset
147 static const struct regset alphanbsd_fpregset
=
150 alphanbsd_supply_fpregset
153 static const struct regset alphanbsd_aout_gregset
=
156 alphanbsd_aout_supply_gregset
159 /* Return the appropriate register set for the core section identified
160 by SECT_NAME and SECT_SIZE. */
162 const struct regset
*
163 alphanbsd_regset_from_core_section (struct gdbarch
*gdbarch
,
164 const char *sect_name
, size_t sect_size
)
166 if (strcmp (sect_name
, ".reg") == 0 && sect_size
>= ALPHANBSD_SIZEOF_GREGS
)
168 if (sect_size
>= ALPHANBSD_SIZEOF_GREGS
+ ALPHANBSD_SIZEOF_FPREGS
)
169 return &alphanbsd_aout_gregset
;
171 return &alphanbsd_gregset
;
174 if (strcmp (sect_name
, ".reg2") == 0 && sect_size
>= ALPHANBSD_SIZEOF_FPREGS
)
175 return &alphanbsd_fpregset
;
181 /* Signal trampolines. */
183 /* Under NetBSD/alpha, signal handler invocations can be identified by the
184 designated code sequence that is used to return from a signal handler.
185 In particular, the return address of a signal handler points to the
186 following code sequence:
190 lda v0, 295(zero) # __sigreturn14
193 Each instruction has a unique encoding, so we simply attempt to match
194 the instruction the PC is pointing to with any of the above instructions.
195 If there is a hit, we know the offset to the start of the designated
196 sequence and can then check whether we really are executing in the
197 signal trampoline. If not, -1 is returned, otherwise the offset from the
198 start of the return sequence is returned. */
199 static const gdb_byte sigtramp_retcode
[] =
201 0x00, 0x00, 0x1e, 0xa6, /* ldq a0, 0(sp) */
202 0x10, 0x00, 0xde, 0x23, /* lda sp, 16(sp) */
203 0x27, 0x01, 0x1f, 0x20, /* lda v0, 295(zero) */
204 0x83, 0x00, 0x00, 0x00, /* call_pal callsys */
206 #define RETCODE_NWORDS 4
207 #define RETCODE_SIZE (RETCODE_NWORDS * 4)
210 alphanbsd_sigtramp_offset (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
212 gdb_byte ret
[RETCODE_SIZE
], w
[4];
216 if (target_read_memory (pc
, w
, 4) != 0)
219 for (i
= 0; i
< RETCODE_NWORDS
; i
++)
221 if (memcmp (w
, sigtramp_retcode
+ (i
* 4), 4) == 0)
224 if (i
== RETCODE_NWORDS
)
230 if (target_read_memory (pc
, ret
, sizeof (ret
)) != 0)
233 if (memcmp (ret
, sigtramp_retcode
, RETCODE_SIZE
) == 0)
240 alphanbsd_pc_in_sigtramp (struct gdbarch
*gdbarch
,
241 CORE_ADDR pc
, const char *func_name
)
243 return (nbsd_pc_in_sigtramp (pc
, func_name
)
244 || alphanbsd_sigtramp_offset (gdbarch
, pc
) >= 0);
248 alphanbsd_sigcontext_addr (struct frame_info
*frame
)
250 /* FIXME: This is not correct for all versions of NetBSD/alpha.
251 We will probably need to disassemble the trampoline to figure
252 out which trampoline frame type we have. */
253 if (!get_next_frame (frame
))
255 return get_frame_base (get_next_frame (frame
));
260 alphanbsd_init_abi (struct gdbarch_info info
,
261 struct gdbarch
*gdbarch
)
263 struct gdbarch_tdep
*tdep
= gdbarch_tdep (gdbarch
);
265 /* Hook into the DWARF CFI frame unwinder. */
266 alpha_dwarf2_init_abi (info
, gdbarch
);
268 /* Hook into the MDEBUG frame unwinder. */
269 alpha_mdebug_init_abi (info
, gdbarch
);
271 /* NetBSD/alpha does not provide single step support via ptrace(2); we
272 must use software single-stepping. */
273 set_gdbarch_software_single_step (gdbarch
, alpha_software_single_step
);
275 /* NetBSD/alpha has SVR4-style shared libraries. */
276 set_solib_svr4_fetch_link_map_offsets
277 (gdbarch
, svr4_lp64_fetch_link_map_offsets
);
279 tdep
->dynamic_sigtramp_offset
= alphanbsd_sigtramp_offset
;
280 tdep
->pc_in_sigtramp
= alphanbsd_pc_in_sigtramp
;
281 tdep
->sigcontext_addr
= alphanbsd_sigcontext_addr
;
284 tdep
->jb_elt_size
= 8;
286 set_gdbarch_regset_from_core_section
287 (gdbarch
, alphanbsd_regset_from_core_section
);
291 static enum gdb_osabi
292 alphanbsd_core_osabi_sniffer (bfd
*abfd
)
294 if (strcmp (bfd_get_target (abfd
), "netbsd-core") == 0)
295 return GDB_OSABI_NETBSD_ELF
;
297 return GDB_OSABI_UNKNOWN
;
301 /* Provide a prototype to silence -Wmissing-prototypes. */
302 void _initialize_alphanbsd_tdep (void);
305 _initialize_alphanbsd_tdep (void)
307 /* BFD doesn't set a flavour for NetBSD style a.out core files. */
308 gdbarch_register_osabi_sniffer (bfd_arch_alpha
, bfd_target_unknown_flavour
,
309 alphanbsd_core_osabi_sniffer
);
311 gdbarch_register_osabi (bfd_arch_alpha
, 0, GDB_OSABI_NETBSD_ELF
,