1 /* Target-dependent code for NetBSD/alpha.
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 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"
31 #include "gdb_string.h"
33 #include "alpha-tdep.h"
34 #include "alphabsd-tdep.h"
35 #include "nbsd-tdep.h"
36 #include "solib-svr4.h"
38 /* Core file support. */
40 /* Even though NetBSD/alpha used ELF since day one, it used the
41 traditional a.out-style core dump format before NetBSD 1.6. */
43 /* Sizeof `struct reg' in <machine/reg.h>. */
44 #define ALPHANBSD_SIZEOF_GREGS (32 * 8)
46 /* Sizeof `struct fpreg' in <machine/reg.h. */
47 #define ALPHANBSD_SIZEOF_FPREGS ((32 * 8) + 8)
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 alphanbsd_supply_fpregset (const struct regset
*regset
,
55 struct regcache
*regcache
,
56 int regnum
, const void *fpregs
, size_t len
)
58 const gdb_byte
*regs
= fpregs
;
61 gdb_assert (len
>= ALPHANBSD_SIZEOF_FPREGS
);
63 for (i
= ALPHA_FP0_REGNUM
; i
< ALPHA_FP0_REGNUM
+ 31; i
++)
65 if (regnum
== i
|| regnum
== -1)
66 regcache_raw_supply (regcache
, i
, regs
+ (i
- ALPHA_FP0_REGNUM
) * 8);
69 if (regnum
== ALPHA_FPCR_REGNUM
|| regnum
== -1)
70 regcache_raw_supply (regcache
, ALPHA_FPCR_REGNUM
, regs
+ 32 * 8);
73 /* Supply register REGNUM from the buffer specified by GREGS and LEN
74 in the general-purpose register set REGSET to register cache
75 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
78 alphanbsd_supply_gregset (const struct regset
*regset
,
79 struct regcache
*regcache
,
80 int regnum
, const void *gregs
, size_t len
)
82 const gdb_byte
*regs
= gregs
;
85 gdb_assert (len
>= ALPHANBSD_SIZEOF_GREGS
);
87 for (i
= 0; i
< ALPHA_ZERO_REGNUM
; i
++)
89 if (regnum
== i
|| regnum
== -1)
90 regcache_raw_supply (regcache
, i
, regs
+ i
* 8);
93 if (regnum
== ALPHA_PC_REGNUM
|| regnum
== -1)
94 regcache_raw_supply (regcache
, ALPHA_PC_REGNUM
, regs
+ 31 * 8);
97 /* Supply register REGNUM from the buffer specified by GREGS and LEN
98 in the general-purpose register set REGSET to register cache
99 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
102 alphanbsd_aout_supply_gregset (const struct regset
*regset
,
103 struct regcache
*regcache
,
104 int regnum
, const void *gregs
, size_t len
)
106 const gdb_byte
*regs
= gregs
;
109 /* Table to map a GDB register number to a trapframe register index. */
110 static const int regmap
[] =
122 gdb_assert (len
>= ALPHANBSD_SIZEOF_GREGS
);
124 for (i
= 0; i
< ARRAY_SIZE(regmap
); i
++)
126 if (regnum
== i
|| regnum
== -1)
127 regcache_raw_supply (regcache
, i
, regs
+ regmap
[i
] * 8);
130 if (regnum
== ALPHA_PC_REGNUM
|| regnum
== -1)
131 regcache_raw_supply (regcache
, ALPHA_PC_REGNUM
, regs
+ 31 * 8);
133 if (len
>= ALPHANBSD_SIZEOF_GREGS
+ ALPHANBSD_SIZEOF_FPREGS
)
135 regs
+= ALPHANBSD_SIZEOF_GREGS
;
136 len
-= ALPHANBSD_SIZEOF_GREGS
;
137 alphanbsd_supply_fpregset (regset
, regcache
, regnum
, regs
, len
);
141 /* NetBSD/alpha register sets. */
143 static struct regset alphanbsd_gregset
=
146 alphanbsd_supply_gregset
149 static struct regset alphanbsd_fpregset
=
152 alphanbsd_supply_fpregset
155 static struct regset alphanbsd_aout_gregset
=
158 alphanbsd_aout_supply_gregset
161 /* Return the appropriate register set for the core section identified
162 by SECT_NAME and SECT_SIZE. */
164 const struct regset
*
165 alphanbsd_regset_from_core_section (struct gdbarch
*gdbarch
,
166 const char *sect_name
, size_t sect_size
)
168 if (strcmp (sect_name
, ".reg") == 0 && sect_size
>= ALPHANBSD_SIZEOF_GREGS
)
170 if (sect_size
>= ALPHANBSD_SIZEOF_GREGS
+ ALPHANBSD_SIZEOF_FPREGS
)
171 return &alphanbsd_aout_gregset
;
173 return &alphanbsd_gregset
;
176 if (strcmp (sect_name
, ".reg2") == 0 && sect_size
>= ALPHANBSD_SIZEOF_FPREGS
)
177 return &alphanbsd_fpregset
;
183 /* Signal trampolines. */
185 /* Under NetBSD/alpha, signal handler invocations can be identified by the
186 designated code sequence that is used to return from a signal handler.
187 In particular, the return address of a signal handler points to the
188 following code sequence:
192 lda v0, 295(zero) # __sigreturn14
195 Each instruction has a unique encoding, so we simply attempt to match
196 the instruction the PC is pointing to with any of the above instructions.
197 If there is a hit, we know the offset to the start of the designated
198 sequence and can then check whether we really are executing in the
199 signal trampoline. If not, -1 is returned, otherwise the offset from the
200 start of the return sequence is returned. */
201 static const unsigned char sigtramp_retcode
[] =
203 0x00, 0x00, 0x1e, 0xa6, /* ldq a0, 0(sp) */
204 0x10, 0x00, 0xde, 0x23, /* lda sp, 16(sp) */
205 0x27, 0x01, 0x1f, 0x20, /* lda v0, 295(zero) */
206 0x83, 0x00, 0x00, 0x00, /* call_pal callsys */
208 #define RETCODE_NWORDS 4
209 #define RETCODE_SIZE (RETCODE_NWORDS * 4)
212 alphanbsd_sigtramp_offset (CORE_ADDR pc
)
214 unsigned char ret
[RETCODE_SIZE
], w
[4];
218 if (read_memory_nobpt (pc
, (char *) w
, 4) != 0)
221 for (i
= 0; i
< RETCODE_NWORDS
; i
++)
223 if (memcmp (w
, sigtramp_retcode
+ (i
* 4), 4) == 0)
226 if (i
== RETCODE_NWORDS
)
232 if (read_memory_nobpt (pc
, (char *) ret
, sizeof (ret
)) != 0)
235 if (memcmp (ret
, sigtramp_retcode
, RETCODE_SIZE
) == 0)
242 alphanbsd_pc_in_sigtramp (CORE_ADDR pc
, char *func_name
)
244 return (nbsd_pc_in_sigtramp (pc
, func_name
)
245 || alphanbsd_sigtramp_offset (pc
) >= 0);
249 alphanbsd_sigcontext_addr (struct frame_info
*frame
)
251 /* FIXME: This is not correct for all versions of NetBSD/alpha.
252 We will probably need to disassemble the trampoline to figure
253 out which trampoline frame type we have. */
254 return get_frame_base (frame
);
259 alphanbsd_init_abi (struct gdbarch_info info
,
260 struct gdbarch
*gdbarch
)
262 struct gdbarch_tdep
*tdep
= gdbarch_tdep (gdbarch
);
264 /* Hook into the DWARF CFI frame unwinder. */
265 alpha_dwarf2_init_abi (info
, gdbarch
);
267 /* Hook into the MDEBUG frame unwinder. */
268 alpha_mdebug_init_abi (info
, gdbarch
);
270 /* NetBSD/alpha does not provide single step support via ptrace(2); we
271 must use software single-stepping. */
272 set_gdbarch_software_single_step (gdbarch
, alpha_software_single_step
);
274 /* NetBSD/alpha has SVR4-style shared libraries. */
275 set_solib_svr4_fetch_link_map_offsets
276 (gdbarch
, svr4_lp64_fetch_link_map_offsets
);
278 tdep
->dynamic_sigtramp_offset
= alphanbsd_sigtramp_offset
;
279 tdep
->pc_in_sigtramp
= alphanbsd_pc_in_sigtramp
;
280 tdep
->sigcontext_addr
= alphanbsd_sigcontext_addr
;
283 tdep
->jb_elt_size
= 8;
285 set_gdbarch_regset_from_core_section
286 (gdbarch
, alphanbsd_regset_from_core_section
);
290 static enum gdb_osabi
291 alphanbsd_core_osabi_sniffer (bfd
*abfd
)
293 if (strcmp (bfd_get_target (abfd
), "netbsd-core") == 0)
294 return GDB_OSABI_NETBSD_ELF
;
296 return GDB_OSABI_UNKNOWN
;
300 /* Provide a prototype to silence -Wmissing-prototypes. */
301 void _initialize_alphanbsd_tdep (void);
304 _initialize_alphanbsd_tdep (void)
306 /* BFD doesn't set a flavour for NetBSD style a.out core files. */
307 gdbarch_register_osabi_sniffer (bfd_arch_alpha
, bfd_target_unknown_flavour
,
308 alphanbsd_core_osabi_sniffer
);
310 gdbarch_register_osabi (bfd_arch_alpha
, 0, GDB_OSABI_NETBSD_ELF
,