1 /* Target-dependent code for OpenBSD/sparc.
3 Copyright (C) 2004-2024 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/>. */
22 #include "frame-unwind.h"
27 #include "trad-frame.h"
30 #include "obsd-tdep.h"
31 #include "sparc-tdep.h"
32 #include "solib-svr4.h"
33 #include "bsd-uthread.h"
36 /* Signal trampolines. */
38 /* The OpenBSD kernel maps the signal trampoline at some random
39 location in user space, which means that the traditional BSD way of
40 detecting it won't work.
42 The signal trampoline will be mapped at an address that is page
43 aligned. We recognize the signal trampoline by looking for the
44 sigreturn system call. */
46 static const int sparc32obsd_page_size
= 4096;
49 sparc32obsd_pc_in_sigtramp (CORE_ADDR pc
, const char *name
)
51 CORE_ADDR start_pc
= (pc
& ~(sparc32obsd_page_size
- 1));
57 /* Check for "restore %g0, SYS_sigreturn, %g1". */
58 insn
= sparc_fetch_instruction (start_pc
+ 0xec);
59 if (insn
!= 0x83e82067)
62 /* Check for "t ST_SYSCALL". */
63 insn
= sparc_fetch_instruction (start_pc
+ 0xf4);
64 if (insn
!= 0x91d02000)
70 static struct sparc_frame_cache
*
71 sparc32obsd_sigtramp_frame_cache (const frame_info_ptr
&this_frame
,
74 struct sparc_frame_cache
*cache
;
78 return (struct sparc_frame_cache
*) *this_cache
;
80 cache
= sparc_frame_cache (this_frame
, this_cache
);
81 gdb_assert (cache
== *this_cache
);
83 /* If we couldn't find the frame's function, we're probably dealing
84 with an on-stack signal trampoline. */
87 cache
->pc
= get_frame_pc (this_frame
);
88 cache
->pc
&= ~(sparc32obsd_page_size
- 1);
90 /* Since we couldn't find the frame's function, the cache was
91 initialized under the assumption that we're frameless. */
92 sparc_record_save_insn (cache
);
93 addr
= get_frame_register_unsigned (this_frame
, SPARC_FP_REGNUM
);
97 cache
->saved_regs
= sparc32nbsd_sigcontext_saved_regs (this_frame
);
103 sparc32obsd_sigtramp_frame_this_id (const frame_info_ptr
&this_frame
,
105 struct frame_id
*this_id
)
107 struct sparc_frame_cache
*cache
=
108 sparc32obsd_sigtramp_frame_cache (this_frame
, this_cache
);
110 (*this_id
) = frame_id_build (cache
->base
, cache
->pc
);
113 static struct value
*
114 sparc32obsd_sigtramp_frame_prev_register (const frame_info_ptr
&this_frame
,
115 void **this_cache
, int regnum
)
117 struct sparc_frame_cache
*cache
=
118 sparc32obsd_sigtramp_frame_cache (this_frame
, this_cache
);
120 return trad_frame_get_prev_register (this_frame
, cache
->saved_regs
, regnum
);
124 sparc32obsd_sigtramp_frame_sniffer (const struct frame_unwind
*self
,
125 const frame_info_ptr
&this_frame
,
128 CORE_ADDR pc
= get_frame_pc (this_frame
);
131 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
132 if (sparc32obsd_pc_in_sigtramp (pc
, name
))
137 static const struct frame_unwind sparc32obsd_sigtramp_frame_unwind
=
139 "sparc32 openbsd sigtramp",
141 default_frame_unwind_stop_reason
,
142 sparc32obsd_sigtramp_frame_this_id
,
143 sparc32obsd_sigtramp_frame_prev_register
,
145 sparc32obsd_sigtramp_frame_sniffer
150 /* Offset wthin the thread structure where we can find %fp and %i7. */
151 #define SPARC32OBSD_UTHREAD_FP_OFFSET 128
152 #define SPARC32OBSD_UTHREAD_PC_OFFSET 132
155 sparc32obsd_supply_uthread (struct regcache
*regcache
,
156 int regnum
, CORE_ADDR addr
)
158 struct gdbarch
*gdbarch
= regcache
->arch ();
159 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
160 CORE_ADDR fp
, fp_addr
= addr
+ SPARC32OBSD_UTHREAD_FP_OFFSET
;
163 /* This function calls functions that depend on the global current thread. */
164 gdb_assert (regcache
->ptid () == inferior_ptid
);
166 gdb_assert (regnum
>= -1);
168 fp
= read_memory_unsigned_integer (fp_addr
, 4, byte_order
);
169 if (regnum
== SPARC_SP_REGNUM
|| regnum
== -1)
171 store_unsigned_integer (buf
, 4, byte_order
, fp
);
172 regcache
->raw_supply (SPARC_SP_REGNUM
, buf
);
174 if (regnum
== SPARC_SP_REGNUM
)
178 if (regnum
== SPARC32_PC_REGNUM
|| regnum
== SPARC32_NPC_REGNUM
181 CORE_ADDR i7
, i7_addr
= addr
+ SPARC32OBSD_UTHREAD_PC_OFFSET
;
183 i7
= read_memory_unsigned_integer (i7_addr
, 4, byte_order
);
184 if (regnum
== SPARC32_PC_REGNUM
|| regnum
== -1)
186 store_unsigned_integer (buf
, 4, byte_order
, i7
+ 8);
187 regcache
->raw_supply (SPARC32_PC_REGNUM
, buf
);
189 if (regnum
== SPARC32_NPC_REGNUM
|| regnum
== -1)
191 store_unsigned_integer (buf
, 4, byte_order
, i7
+ 12);
192 regcache
->raw_supply (SPARC32_NPC_REGNUM
, buf
);
195 if (regnum
== SPARC32_PC_REGNUM
|| regnum
== SPARC32_NPC_REGNUM
)
199 sparc_supply_rwindow (regcache
, fp
, regnum
);
203 sparc32obsd_collect_uthread(const struct regcache
*regcache
,
204 int regnum
, CORE_ADDR addr
)
206 struct gdbarch
*gdbarch
= regcache
->arch ();
207 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
211 /* This function calls functions that depend on the global current thread. */
212 gdb_assert (regcache
->ptid () == inferior_ptid
);
214 gdb_assert (regnum
>= -1);
216 if (regnum
== SPARC_SP_REGNUM
|| regnum
== -1)
218 CORE_ADDR fp_addr
= addr
+ SPARC32OBSD_UTHREAD_FP_OFFSET
;
220 regcache
->raw_collect (SPARC_SP_REGNUM
, buf
);
221 write_memory (fp_addr
,buf
, 4);
224 if (regnum
== SPARC32_PC_REGNUM
|| regnum
== -1)
226 CORE_ADDR i7
, i7_addr
= addr
+ SPARC32OBSD_UTHREAD_PC_OFFSET
;
228 regcache
->raw_collect (SPARC32_PC_REGNUM
, buf
);
229 i7
= extract_unsigned_integer (buf
, 4, byte_order
) - 8;
230 write_memory_unsigned_integer (i7_addr
, 4, byte_order
, i7
);
232 if (regnum
== SPARC32_PC_REGNUM
)
236 regcache
->raw_collect (SPARC_SP_REGNUM
, buf
);
237 sp
= extract_unsigned_integer (buf
, 4, byte_order
);
238 sparc_collect_rwindow (regcache
, sp
, regnum
);
243 sparc32obsd_init_abi (struct gdbarch_info info
, struct gdbarch
*gdbarch
)
245 /* OpenBSD/sparc is very similar to NetBSD/sparc ELF. */
246 sparc32nbsd_init_abi (info
, gdbarch
);
248 set_gdbarch_skip_solib_resolver (gdbarch
, obsd_skip_solib_resolver
);
250 frame_unwind_append_unwinder (gdbarch
, &sparc32obsd_sigtramp_frame_unwind
);
252 /* OpenBSD provides a user-level threads implementation. */
253 bsd_uthread_set_supply_uthread (gdbarch
, sparc32obsd_supply_uthread
);
254 bsd_uthread_set_collect_uthread (gdbarch
, sparc32obsd_collect_uthread
);
257 void _initialize_sparc32obsd_tdep ();
259 _initialize_sparc32obsd_tdep ()
261 gdbarch_register_osabi (bfd_arch_sparc
, 0, GDB_OSABI_OPENBSD
,
262 sparc32obsd_init_abi
);