1 /* Target-dependent code for OpenBSD/sparc.
3 Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "floatformat.h"
23 #include "frame-unwind.h"
28 #include "trad-frame.h"
30 #include "gdb_assert.h"
32 #include "obsd-tdep.h"
33 #include "sparc-tdep.h"
34 #include "solib-svr4.h"
35 #include "bsd-uthread.h"
37 /* Signal trampolines. */
39 /* The OpenBSD kernel maps the signal trampoline at some random
40 location in user space, which means that the traditional BSD way of
41 detecting it won't work.
43 The signal trampoline will be mapped at an address that is page
44 aligned. We recognize the signal trampoline by looking for the
45 sigreturn system call. */
47 static const int sparc32obsd_page_size
= 4096;
50 sparc32obsd_pc_in_sigtramp (CORE_ADDR pc
, char *name
)
52 CORE_ADDR start_pc
= (pc
& ~(sparc32obsd_page_size
- 1));
58 /* Check for "restore %g0, SYS_sigreturn, %g1". */
59 insn
= sparc_fetch_instruction (start_pc
+ 0xec);
60 if (insn
!= 0x83e82067)
63 /* Check for "t ST_SYSCALL". */
64 insn
= sparc_fetch_instruction (start_pc
+ 0xf4);
65 if (insn
!= 0x91d02000)
71 static struct sparc_frame_cache
*
72 sparc32obsd_sigtramp_frame_cache (struct frame_info
*this_frame
,
75 struct sparc_frame_cache
*cache
;
81 cache
= sparc_frame_cache (this_frame
, this_cache
);
82 gdb_assert (cache
== *this_cache
);
84 /* If we couldn't find the frame's function, we're probably dealing
85 with an on-stack signal trampoline. */
88 cache
->pc
= get_frame_pc (this_frame
);
89 cache
->pc
&= ~(sparc32obsd_page_size
- 1);
91 /* Since we couldn't find the frame's function, the cache was
92 initialized under the assumption that we're frameless. */
93 cache
->frameless_p
= 0;
94 addr
= get_frame_register_unsigned (this_frame
, SPARC_FP_REGNUM
);
98 cache
->saved_regs
= sparc32nbsd_sigcontext_saved_regs (this_frame
);
104 sparc32obsd_sigtramp_frame_this_id (struct frame_info
*this_frame
,
106 struct frame_id
*this_id
)
108 struct sparc_frame_cache
*cache
=
109 sparc32obsd_sigtramp_frame_cache (this_frame
, this_cache
);
111 (*this_id
) = frame_id_build (cache
->base
, cache
->pc
);
114 static struct value
*
115 sparc32obsd_sigtramp_frame_prev_register (struct frame_info
*this_frame
,
116 void **this_cache
, int regnum
)
118 struct sparc_frame_cache
*cache
=
119 sparc32obsd_sigtramp_frame_cache (this_frame
, this_cache
);
121 return trad_frame_get_prev_register (this_frame
, cache
->saved_regs
, regnum
);
125 sparc32obsd_sigtramp_frame_sniffer (const struct frame_unwind
*self
,
126 struct frame_info
*this_frame
,
129 CORE_ADDR pc
= get_frame_pc (this_frame
);
132 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
133 if (sparc32obsd_pc_in_sigtramp (pc
, name
))
138 static const struct frame_unwind sparc32obsd_sigtramp_frame_unwind
=
141 sparc32obsd_sigtramp_frame_this_id
,
142 sparc32obsd_sigtramp_frame_prev_register
,
144 sparc32obsd_sigtramp_frame_sniffer
149 /* Offset wthin the thread structure where we can find %fp and %i7. */
150 #define SPARC32OBSD_UTHREAD_FP_OFFSET 128
151 #define SPARC32OBSD_UTHREAD_PC_OFFSET 132
154 sparc32obsd_supply_uthread (struct regcache
*regcache
,
155 int regnum
, CORE_ADDR addr
)
157 CORE_ADDR fp
, fp_addr
= addr
+ SPARC32OBSD_UTHREAD_FP_OFFSET
;
160 gdb_assert (regnum
>= -1);
162 fp
= read_memory_unsigned_integer (fp_addr
, 4);
163 if (regnum
== SPARC_SP_REGNUM
|| regnum
== -1)
165 store_unsigned_integer (buf
, 4, fp
);
166 regcache_raw_supply (regcache
, SPARC_SP_REGNUM
, buf
);
168 if (regnum
== SPARC_SP_REGNUM
)
172 if (regnum
== SPARC32_PC_REGNUM
|| regnum
== SPARC32_NPC_REGNUM
175 CORE_ADDR i7
, i7_addr
= addr
+ SPARC32OBSD_UTHREAD_PC_OFFSET
;
177 i7
= read_memory_unsigned_integer (i7_addr
, 4);
178 if (regnum
== SPARC32_PC_REGNUM
|| regnum
== -1)
180 store_unsigned_integer (buf
, 4, i7
+ 8);
181 regcache_raw_supply (regcache
, SPARC32_PC_REGNUM
, buf
);
183 if (regnum
== SPARC32_NPC_REGNUM
|| regnum
== -1)
185 store_unsigned_integer (buf
, 4, i7
+ 12);
186 regcache_raw_supply (regcache
, SPARC32_NPC_REGNUM
, buf
);
189 if (regnum
== SPARC32_PC_REGNUM
|| regnum
== SPARC32_NPC_REGNUM
)
193 sparc_supply_rwindow (regcache
, fp
, regnum
);
197 sparc32obsd_collect_uthread(const struct regcache
*regcache
,
198 int regnum
, CORE_ADDR addr
)
203 gdb_assert (regnum
>= -1);
205 if (regnum
== SPARC_SP_REGNUM
|| regnum
== -1)
207 CORE_ADDR fp_addr
= addr
+ SPARC32OBSD_UTHREAD_FP_OFFSET
;
209 regcache_raw_collect (regcache
, SPARC_SP_REGNUM
, buf
);
210 write_memory (fp_addr
,buf
, 4);
213 if (regnum
== SPARC32_PC_REGNUM
|| regnum
== -1)
215 CORE_ADDR i7
, i7_addr
= addr
+ SPARC32OBSD_UTHREAD_PC_OFFSET
;
217 regcache_raw_collect (regcache
, SPARC32_PC_REGNUM
, buf
);
218 i7
= extract_unsigned_integer (buf
, 4) - 8;
219 write_memory_unsigned_integer (i7_addr
, 4, i7
);
221 if (regnum
== SPARC32_PC_REGNUM
)
225 regcache_raw_collect (regcache
, SPARC_SP_REGNUM
, buf
);
226 sp
= extract_unsigned_integer (buf
, 4);
227 sparc_collect_rwindow (regcache
, sp
, regnum
);
232 sparc32obsd_init_abi (struct gdbarch_info info
, struct gdbarch
*gdbarch
)
234 struct gdbarch_tdep
*tdep
= gdbarch_tdep (gdbarch
);
236 /* OpenBSD/sparc is very similar to NetBSD/sparc ELF. */
237 sparc32nbsd_elf_init_abi (info
, gdbarch
);
239 set_gdbarch_skip_solib_resolver (gdbarch
, obsd_skip_solib_resolver
);
241 frame_unwind_append_unwinder (gdbarch
, &sparc32obsd_sigtramp_frame_unwind
);
243 /* OpenBSD provides a user-level threads implementation. */
244 bsd_uthread_set_supply_uthread (gdbarch
, sparc32obsd_supply_uthread
);
245 bsd_uthread_set_collect_uthread (gdbarch
, sparc32obsd_collect_uthread
);
249 /* Provide a prototype to silence -Wmissing-prototypes. */
250 void _initialize_sparc32obsd_tdep (void);
253 _initialize_sparc32obsd_tdep (void)
255 gdbarch_register_osabi (bfd_arch_sparc
, 0, GDB_OSABI_OPENBSD_ELF
,
256 sparc32obsd_init_abi
);