Commit | Line | Data |
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0a595803 AS |
1 | /* Motorola m68k target-dependent support for GNU/Linux. |
2 | ||
9b254dd1 | 3 | Copyright (C) 1996, 1998, 2000, 2001, 2002, 2003, 2004, 2007, 2008 |
f595cb19 | 4 | Free Software Foundation, Inc. |
0a595803 AS |
5 | |
6 | This file is part of GDB. | |
7 | ||
8 | This program is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 10 | the Free Software Foundation; either version 3 of the License, or |
0a595803 AS |
11 | (at your option) any later version. |
12 | ||
13 | This program is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
0a595803 AS |
20 | |
21 | #include "defs.h" | |
22 | #include "gdbcore.h" | |
8de307e0 AS |
23 | #include "doublest.h" |
24 | #include "floatformat.h" | |
0a595803 AS |
25 | #include "frame.h" |
26 | #include "target.h" | |
d0b45d99 AS |
27 | #include "gdb_string.h" |
28 | #include "gdbtypes.h" | |
55809acb | 29 | #include "osabi.h" |
eb2e12d7 AS |
30 | #include "regcache.h" |
31 | #include "objfiles.h" | |
32 | #include "symtab.h" | |
d0b45d99 | 33 | #include "m68k-tdep.h" |
17e20bce AC |
34 | #include "trad-frame.h" |
35 | #include "frame-unwind.h" | |
fefa1888 AS |
36 | #include "glibc-tdep.h" |
37 | #include "solib-svr4.h" | |
0ebdb728 MS |
38 | #include "auxv.h" |
39 | #include "observer.h" | |
40 | #include "elf/common.h" | |
0a595803 | 41 | \f |
eb2e12d7 AS |
42 | /* Offsets (in target ints) into jmp_buf. */ |
43 | ||
44 | #define M68K_LINUX_JB_ELEMENT_SIZE 4 | |
45 | #define M68K_LINUX_JB_PC 7 | |
46 | ||
0a595803 AS |
47 | /* Check whether insn1 and insn2 are parts of a signal trampoline. */ |
48 | ||
49 | #define IS_SIGTRAMP(insn1, insn2) \ | |
50 | (/* addaw #20,sp; moveq #119,d0; trap #0 */ \ | |
51 | (insn1 == 0xdefc0014 && insn2 == 0x70774e40) \ | |
52 | /* moveq #119,d0; trap #0 */ \ | |
53 | || insn1 == 0x70774e40) | |
54 | ||
55 | #define IS_RT_SIGTRAMP(insn1, insn2) \ | |
56 | (/* movel #173,d0; trap #0 */ \ | |
57 | (insn1 == 0x203c0000 && insn2 == 0x00ad4e40) \ | |
58 | /* moveq #82,d0; notb d0; trap #0 */ \ | |
59 | || (insn1 == 0x70524600 && (insn2 >> 16) == 0x4e40)) | |
60 | ||
8de307e0 AS |
61 | /* Return non-zero if PC points into the signal trampoline. For the |
62 | sake of m68k_linux_get_sigtramp_info we also distinguish between | |
63 | non-RT and RT signal trampolines. */ | |
0a595803 | 64 | |
eb2e12d7 AS |
65 | static int |
66 | m68k_linux_pc_in_sigtramp (CORE_ADDR pc, char *name) | |
0a595803 AS |
67 | { |
68 | CORE_ADDR sp; | |
69 | char buf[12]; | |
70 | unsigned long insn0, insn1, insn2; | |
71 | ||
8defab1a | 72 | if (target_read_memory (pc - 4, buf, sizeof (buf))) |
0a595803 AS |
73 | return 0; |
74 | insn1 = extract_unsigned_integer (buf + 4, 4); | |
75 | insn2 = extract_unsigned_integer (buf + 8, 4); | |
76 | if (IS_SIGTRAMP (insn1, insn2)) | |
77 | return 1; | |
78 | if (IS_RT_SIGTRAMP (insn1, insn2)) | |
79 | return 2; | |
80 | ||
81 | insn0 = extract_unsigned_integer (buf, 4); | |
82 | if (IS_SIGTRAMP (insn0, insn1)) | |
83 | return 1; | |
84 | if (IS_RT_SIGTRAMP (insn0, insn1)) | |
85 | return 2; | |
86 | ||
55809acb AS |
87 | insn0 = ((insn0 << 16) & 0xffffffff) | (insn1 >> 16); |
88 | insn1 = ((insn1 << 16) & 0xffffffff) | (insn2 >> 16); | |
0a595803 AS |
89 | if (IS_SIGTRAMP (insn0, insn1)) |
90 | return 1; | |
91 | if (IS_RT_SIGTRAMP (insn0, insn1)) | |
92 | return 2; | |
93 | ||
94 | return 0; | |
95 | } | |
96 | ||
8de307e0 AS |
97 | /* From <asm/sigcontext.h>. */ |
98 | static int m68k_linux_sigcontext_reg_offset[M68K_NUM_REGS] = | |
0a595803 | 99 | { |
8de307e0 AS |
100 | 2 * 4, /* %d0 */ |
101 | 3 * 4, /* %d1 */ | |
102 | -1, /* %d2 */ | |
103 | -1, /* %d3 */ | |
104 | -1, /* %d4 */ | |
105 | -1, /* %d5 */ | |
106 | -1, /* %d6 */ | |
107 | -1, /* %d7 */ | |
108 | 4 * 4, /* %a0 */ | |
109 | 5 * 4, /* %a1 */ | |
110 | -1, /* %a2 */ | |
111 | -1, /* %a3 */ | |
112 | -1, /* %a4 */ | |
113 | -1, /* %a5 */ | |
114 | -1, /* %fp */ | |
115 | 1 * 4, /* %sp */ | |
0ebdb728 | 116 | 6 * 4, /* %sr */ |
8de307e0 AS |
117 | 6 * 4 + 2, /* %pc */ |
118 | 8 * 4, /* %fp0 */ | |
119 | 11 * 4, /* %fp1 */ | |
120 | -1, /* %fp2 */ | |
121 | -1, /* %fp3 */ | |
122 | -1, /* %fp4 */ | |
123 | -1, /* %fp5 */ | |
124 | -1, /* %fp6 */ | |
125 | -1, /* %fp7 */ | |
126 | 14 * 4, /* %fpcr */ | |
127 | 15 * 4, /* %fpsr */ | |
128 | 16 * 4 /* %fpiaddr */ | |
129 | }; | |
130 | ||
0ebdb728 MS |
131 | static int m68k_uclinux_sigcontext_reg_offset[M68K_NUM_REGS] = |
132 | { | |
133 | 2 * 4, /* %d0 */ | |
134 | 3 * 4, /* %d1 */ | |
135 | -1, /* %d2 */ | |
136 | -1, /* %d3 */ | |
137 | -1, /* %d4 */ | |
138 | -1, /* %d5 */ | |
139 | -1, /* %d6 */ | |
140 | -1, /* %d7 */ | |
141 | 4 * 4, /* %a0 */ | |
142 | 5 * 4, /* %a1 */ | |
143 | -1, /* %a2 */ | |
144 | -1, /* %a3 */ | |
145 | -1, /* %a4 */ | |
146 | 6 * 4, /* %a5 */ | |
147 | -1, /* %fp */ | |
148 | 1 * 4, /* %sp */ | |
149 | 7 * 4, /* %sr */ | |
150 | 7 * 4 + 2, /* %pc */ | |
151 | -1, /* %fp0 */ | |
152 | -1, /* %fp1 */ | |
153 | -1, /* %fp2 */ | |
154 | -1, /* %fp3 */ | |
155 | -1, /* %fp4 */ | |
156 | -1, /* %fp5 */ | |
157 | -1, /* %fp6 */ | |
158 | -1, /* %fp7 */ | |
159 | -1, /* %fpcr */ | |
160 | -1, /* %fpsr */ | |
161 | -1 /* %fpiaddr */ | |
162 | }; | |
163 | ||
8de307e0 AS |
164 | /* From <asm/ucontext.h>. */ |
165 | static int m68k_linux_ucontext_reg_offset[M68K_NUM_REGS] = | |
166 | { | |
167 | 6 * 4, /* %d0 */ | |
168 | 7 * 4, /* %d1 */ | |
169 | 8 * 4, /* %d2 */ | |
170 | 9 * 4, /* %d3 */ | |
171 | 10 * 4, /* %d4 */ | |
172 | 11 * 4, /* %d5 */ | |
173 | 12 * 4, /* %d6 */ | |
174 | 13 * 4, /* %d7 */ | |
175 | 14 * 4, /* %a0 */ | |
176 | 15 * 4, /* %a1 */ | |
177 | 16 * 4, /* %a2 */ | |
178 | 17 * 4, /* %a3 */ | |
179 | 18 * 4, /* %a4 */ | |
180 | 19 * 4, /* %a5 */ | |
181 | 20 * 4, /* %fp */ | |
182 | 21 * 4, /* %sp */ | |
183 | 23 * 4, /* %sr */ | |
184 | 22 * 4, /* %pc */ | |
185 | 27 * 4, /* %fp0 */ | |
186 | 30 * 4, /* %fp1 */ | |
187 | 33 * 4, /* %fp2 */ | |
188 | 36 * 4, /* %fp3 */ | |
189 | 39 * 4, /* %fp4 */ | |
190 | 42 * 4, /* %fp5 */ | |
191 | 45 * 4, /* %fp6 */ | |
192 | 48 * 4, /* %fp7 */ | |
193 | 24 * 4, /* %fpcr */ | |
194 | 25 * 4, /* %fpsr */ | |
195 | 26 * 4 /* %fpiaddr */ | |
196 | }; | |
197 | ||
198 | ||
199 | /* Get info about saved registers in sigtramp. */ | |
200 | ||
17e20bce AC |
201 | struct m68k_linux_sigtramp_info |
202 | { | |
203 | /* Address of sigcontext. */ | |
204 | CORE_ADDR sigcontext_addr; | |
205 | ||
206 | /* Offset of registers in `struct sigcontext'. */ | |
207 | int *sc_reg_offset; | |
208 | }; | |
209 | ||
0ebdb728 MS |
210 | /* Nonzero if running on uClinux. */ |
211 | static int target_is_uclinux; | |
212 | ||
213 | static void | |
214 | m68k_linux_inferior_created (struct target_ops *objfile, int from_tty) | |
215 | { | |
e9efe249 UW |
216 | /* Record that we will need to re-evaluate whether we are running on a |
217 | uClinux or normal GNU/Linux target (see m68k_linux_get_sigtramp_info). */ | |
0ebdb728 MS |
218 | target_is_uclinux = -1; |
219 | } | |
220 | ||
17e20bce | 221 | static struct m68k_linux_sigtramp_info |
8de307e0 AS |
222 | m68k_linux_get_sigtramp_info (struct frame_info *next_frame) |
223 | { | |
224 | CORE_ADDR sp; | |
225 | char buf[4]; | |
17e20bce | 226 | struct m68k_linux_sigtramp_info info; |
8de307e0 | 227 | |
0ebdb728 MS |
228 | if (target_is_uclinux == -1) |
229 | { | |
e9efe249 | 230 | /* Determine whether we are running on a uClinux or normal GNU/Linux |
0ebdb728 MS |
231 | target so we can use the correct sigcontext layouts. */ |
232 | ||
233 | CORE_ADDR dummy; | |
234 | ||
235 | target_is_uclinux | |
236 | = target_auxv_search (¤t_target, AT_NULL, &dummy) > 0 | |
237 | && target_auxv_search (¤t_target, AT_PAGESZ, &dummy) == 0; | |
238 | } | |
239 | ||
8de307e0 AS |
240 | frame_unwind_register (next_frame, M68K_SP_REGNUM, buf); |
241 | sp = extract_unsigned_integer (buf, 4); | |
0a595803 AS |
242 | |
243 | /* Get sigcontext address, it is the third parameter on the stack. */ | |
8de307e0 AS |
244 | info.sigcontext_addr = read_memory_unsigned_integer (sp + 8, 4); |
245 | ||
246 | if (m68k_linux_pc_in_sigtramp (frame_pc_unwind (next_frame), 0) == 2) | |
247 | info.sc_reg_offset = m68k_linux_ucontext_reg_offset; | |
0a595803 | 248 | else |
0ebdb728 MS |
249 | info.sc_reg_offset |
250 | = target_is_uclinux ? m68k_uclinux_sigcontext_reg_offset | |
251 | : m68k_linux_sigcontext_reg_offset; | |
8de307e0 | 252 | return info; |
0a595803 AS |
253 | } |
254 | ||
17e20bce AC |
255 | /* Signal trampolines. */ |
256 | ||
257 | static struct trad_frame_cache * | |
258 | m68k_linux_sigtramp_frame_cache (struct frame_info *next_frame, | |
259 | void **this_cache) | |
260 | { | |
261 | struct frame_id this_id; | |
262 | struct trad_frame_cache *cache; | |
c984b7ff | 263 | struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (next_frame)); |
17e20bce AC |
264 | struct m68k_linux_sigtramp_info info; |
265 | char buf[4]; | |
266 | int i; | |
267 | ||
268 | if (*this_cache) | |
269 | return *this_cache; | |
270 | ||
271 | cache = trad_frame_cache_zalloc (next_frame); | |
272 | ||
273 | /* FIXME: cagney/2004-05-01: This is is long standing broken code. | |
274 | The frame ID's code address should be the start-address of the | |
275 | signal trampoline and not the current PC within that | |
276 | trampoline. */ | |
277 | frame_unwind_register (next_frame, M68K_SP_REGNUM, buf); | |
278 | /* See the end of m68k_push_dummy_call. */ | |
279 | this_id = frame_id_build (extract_unsigned_integer (buf, 4) - 4 + 8, | |
280 | frame_pc_unwind (next_frame)); | |
281 | trad_frame_set_id (cache, this_id); | |
282 | ||
283 | info = m68k_linux_get_sigtramp_info (next_frame); | |
284 | ||
285 | for (i = 0; i < M68K_NUM_REGS; i++) | |
286 | if (info.sc_reg_offset[i] != -1) | |
287 | trad_frame_set_reg_addr (cache, i, | |
288 | info.sigcontext_addr + info.sc_reg_offset[i]); | |
289 | ||
290 | *this_cache = cache; | |
291 | return cache; | |
292 | } | |
293 | ||
294 | static void | |
295 | m68k_linux_sigtramp_frame_this_id (struct frame_info *next_frame, | |
296 | void **this_cache, | |
297 | struct frame_id *this_id) | |
298 | { | |
299 | struct trad_frame_cache *cache = | |
300 | m68k_linux_sigtramp_frame_cache (next_frame, this_cache); | |
301 | trad_frame_get_id (cache, this_id); | |
302 | } | |
303 | ||
304 | static void | |
305 | m68k_linux_sigtramp_frame_prev_register (struct frame_info *next_frame, | |
306 | void **this_cache, | |
307 | int regnum, int *optimizedp, | |
308 | enum lval_type *lvalp, | |
309 | CORE_ADDR *addrp, | |
cba5fab9 | 310 | int *realnump, gdb_byte *valuep) |
17e20bce AC |
311 | { |
312 | /* Make sure we've initialized the cache. */ | |
313 | struct trad_frame_cache *cache = | |
314 | m68k_linux_sigtramp_frame_cache (next_frame, this_cache); | |
315 | trad_frame_get_register (cache, next_frame, regnum, optimizedp, lvalp, | |
316 | addrp, realnump, valuep); | |
317 | } | |
318 | ||
319 | static const struct frame_unwind m68k_linux_sigtramp_frame_unwind = | |
320 | { | |
321 | SIGTRAMP_FRAME, | |
322 | m68k_linux_sigtramp_frame_this_id, | |
323 | m68k_linux_sigtramp_frame_prev_register | |
324 | }; | |
325 | ||
326 | static const struct frame_unwind * | |
327 | m68k_linux_sigtramp_frame_sniffer (struct frame_info *next_frame) | |
328 | { | |
329 | CORE_ADDR pc = frame_pc_unwind (next_frame); | |
330 | char *name; | |
331 | ||
332 | find_pc_partial_function (pc, &name, NULL, NULL); | |
333 | if (m68k_linux_pc_in_sigtramp (pc, name)) | |
334 | return &m68k_linux_sigtramp_frame_unwind; | |
335 | ||
336 | return NULL; | |
337 | } | |
338 | ||
55809acb AS |
339 | static void |
340 | m68k_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) | |
341 | { | |
eb2e12d7 AS |
342 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
343 | ||
344 | tdep->jb_pc = M68K_LINUX_JB_PC; | |
345 | tdep->jb_elt_size = M68K_LINUX_JB_ELEMENT_SIZE; | |
346 | ||
f595cb19 | 347 | /* GNU/Linux uses a calling convention that's similar to SVR4. It |
8d3239d5 | 348 | returns integer values in %d0/%d1, pointer values in %a0 and |
f595cb19 MK |
349 | floating values in %fp0, just like SVR4, but uses %a1 to pass the |
350 | address to store a structure value. It also returns small | |
351 | structures in registers instead of memory. */ | |
352 | m68k_svr4_init_abi (info, gdbarch); | |
353 | tdep->struct_value_regnum = M68K_A1_REGNUM; | |
354 | tdep->struct_return = reg_struct_return; | |
eb2e12d7 | 355 | |
9418f048 UW |
356 | set_gdbarch_decr_pc_after_break (gdbarch, 2); |
357 | ||
17e20bce | 358 | frame_unwind_append_sniffer (gdbarch, m68k_linux_sigtramp_frame_sniffer); |
eb2e12d7 AS |
359 | |
360 | /* Shared library handling. */ | |
fefa1888 AS |
361 | |
362 | /* GNU/Linux uses SVR4-style shared libraries. */ | |
363 | set_solib_svr4_fetch_link_map_offsets (gdbarch, | |
364 | svr4_ilp32_fetch_link_map_offsets); | |
365 | ||
366 | /* GNU/Linux uses the dynamic linker included in the GNU C Library. */ | |
367 | set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver); | |
368 | ||
eb2e12d7 | 369 | set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); |
b2756930 KB |
370 | |
371 | /* Enable TLS support. */ | |
372 | set_gdbarch_fetch_tls_load_module_address (gdbarch, | |
373 | svr4_fetch_objfile_link_map); | |
55809acb AS |
374 | } |
375 | ||
376 | void | |
377 | _initialize_m68k_linux_tdep (void) | |
378 | { | |
379 | gdbarch_register_osabi (bfd_arch_m68k, 0, GDB_OSABI_LINUX, | |
380 | m68k_linux_init_abi); | |
0ebdb728 | 381 | observer_attach_inferior_created (m68k_linux_inferior_created); |
55809acb | 382 | } |