Commit | Line | Data |
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f2ebc25f | 1 | /* Intel 386 target-dependent stuff. |
c98fe0c1 JI |
2 | Copyright (C) 1988, 1989, 1991, 1994, 1995, 1996, 1998 |
3 | Free Software Foundation, Inc. | |
bd5635a1 RP |
4 | |
5 | This file is part of GDB. | |
6 | ||
7d9884b9 | 7 | This program is free software; you can redistribute it and/or modify |
bd5635a1 | 8 | it under the terms of the GNU General Public License as published by |
7d9884b9 JG |
9 | the Free Software Foundation; either version 2 of the License, or |
10 | (at your option) any later version. | |
bd5635a1 | 11 | |
7d9884b9 | 12 | This program is distributed in the hope that it will be useful, |
bd5635a1 RP |
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. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
7d9884b9 | 18 | along with this program; if not, write to the Free Software |
f33b2c13 | 19 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
bd5635a1 | 20 | |
bd5635a1 | 21 | #include "defs.h" |
f33b2c13 | 22 | #include "gdb_string.h" |
bd5635a1 RP |
23 | #include "frame.h" |
24 | #include "inferior.h" | |
25 | #include "gdbcore.h" | |
51b57ded | 26 | #include "target.h" |
eae3f093 | 27 | #include "floatformat.h" |
28ee4b42 | 28 | #include "symtab.h" |
f33b2c13 | 29 | #include "gdbcmd.h" |
c98fe0c1 | 30 | #include "command.h" |
bd5635a1 | 31 | |
f33b2c13 | 32 | static long i386_get_frame_setup PARAMS ((CORE_ADDR)); |
d747e0af | 33 | |
1a494973 | 34 | static void i386_follow_jump PARAMS ((void)); |
d747e0af | 35 | |
1a494973 | 36 | static void codestream_read PARAMS ((unsigned char *, int)); |
d747e0af | 37 | |
f33b2c13 | 38 | static void codestream_seek PARAMS ((CORE_ADDR)); |
d747e0af | 39 | |
f33b2c13 | 40 | static unsigned char codestream_fill PARAMS ((int)); |
bd5635a1 | 41 | |
c98fe0c1 JI |
42 | CORE_ADDR skip_trampoline_code PARAMS ((CORE_ADDR, char *)); |
43 | ||
44 | static int gdb_print_insn_i386 (bfd_vma, disassemble_info *); | |
45 | ||
46 | void _initialize_i386_tdep PARAMS ((void)); | |
47 | ||
48 | /* This is the variable the is set with "set disassembly-flavor", | |
49 | and its legitimate values. */ | |
50 | static char att_flavor[] = "att"; | |
51 | static char intel_flavor[] = "intel"; | |
52 | static char *valid_flavors[] = { | |
53 | att_flavor, | |
54 | intel_flavor, | |
55 | NULL | |
56 | }; | |
57 | static char *disassembly_flavor = att_flavor; | |
58 | ||
59 | /* Get rid of these defines as soon as there are two functions | |
60 | to implement different disassembly flavors. */ | |
61 | #define print_insn_i386_att print_insn_i386 | |
62 | #define print_insn_i386_intel print_insn_i386 | |
63 | ||
d747e0af MT |
64 | /* Stdio style buffering was used to minimize calls to ptrace, but this |
65 | buffering did not take into account that the code section being accessed | |
66 | may not be an even number of buffers long (even if the buffer is only | |
67 | sizeof(int) long). In cases where the code section size happened to | |
68 | be a non-integral number of buffers long, attempting to read the last | |
69 | buffer would fail. Simply using target_read_memory and ignoring errors, | |
70 | rather than read_memory, is not the correct solution, since legitimate | |
71 | access errors would then be totally ignored. To properly handle this | |
72 | situation and continue to use buffering would require that this code | |
73 | be able to determine the minimum code section size granularity (not the | |
74 | alignment of the section itself, since the actual failing case that | |
75 | pointed out this problem had a section alignment of 4 but was not a | |
76 | multiple of 4 bytes long), on a target by target basis, and then | |
77 | adjust it's buffer size accordingly. This is messy, but potentially | |
78 | feasible. It probably needs the bfd library's help and support. For | |
79 | now, the buffer size is set to 1. (FIXME -fnf) */ | |
80 | ||
81 | #define CODESTREAM_BUFSIZ 1 /* Was sizeof(int), see note above. */ | |
bd5635a1 RP |
82 | static CORE_ADDR codestream_next_addr; |
83 | static CORE_ADDR codestream_addr; | |
d747e0af | 84 | static unsigned char codestream_buf[CODESTREAM_BUFSIZ]; |
bd5635a1 RP |
85 | static int codestream_off; |
86 | static int codestream_cnt; | |
87 | ||
88 | #define codestream_tell() (codestream_addr + codestream_off) | |
89 | #define codestream_peek() (codestream_cnt == 0 ? \ | |
90 | codestream_fill(1): codestream_buf[codestream_off]) | |
91 | #define codestream_get() (codestream_cnt-- == 0 ? \ | |
92 | codestream_fill(0) : codestream_buf[codestream_off++]) | |
93 | ||
94 | static unsigned char | |
95 | codestream_fill (peek_flag) | |
d747e0af | 96 | int peek_flag; |
bd5635a1 RP |
97 | { |
98 | codestream_addr = codestream_next_addr; | |
d747e0af | 99 | codestream_next_addr += CODESTREAM_BUFSIZ; |
bd5635a1 | 100 | codestream_off = 0; |
d747e0af | 101 | codestream_cnt = CODESTREAM_BUFSIZ; |
34df79fc | 102 | read_memory (codestream_addr, (char *) codestream_buf, CODESTREAM_BUFSIZ); |
bd5635a1 RP |
103 | |
104 | if (peek_flag) | |
105 | return (codestream_peek()); | |
106 | else | |
107 | return (codestream_get()); | |
108 | } | |
109 | ||
110 | static void | |
111 | codestream_seek (place) | |
f33b2c13 | 112 | CORE_ADDR place; |
bd5635a1 | 113 | { |
d747e0af MT |
114 | codestream_next_addr = place / CODESTREAM_BUFSIZ; |
115 | codestream_next_addr *= CODESTREAM_BUFSIZ; | |
bd5635a1 RP |
116 | codestream_cnt = 0; |
117 | codestream_fill (1); | |
118 | while (codestream_tell() != place) | |
119 | codestream_get (); | |
120 | } | |
121 | ||
122 | static void | |
123 | codestream_read (buf, count) | |
124 | unsigned char *buf; | |
d747e0af | 125 | int count; |
bd5635a1 RP |
126 | { |
127 | unsigned char *p; | |
128 | int i; | |
129 | p = buf; | |
130 | for (i = 0; i < count; i++) | |
131 | *p++ = codestream_get (); | |
132 | } | |
133 | ||
134 | /* next instruction is a jump, move to target */ | |
d747e0af MT |
135 | |
136 | static void | |
bd5635a1 RP |
137 | i386_follow_jump () |
138 | { | |
28ee4b42 PS |
139 | unsigned char buf[4]; |
140 | long delta; | |
141 | ||
bd5635a1 | 142 | int data16; |
28ee4b42 PS |
143 | CORE_ADDR pos; |
144 | ||
bd5635a1 | 145 | pos = codestream_tell (); |
28ee4b42 | 146 | |
bd5635a1 RP |
147 | data16 = 0; |
148 | if (codestream_peek () == 0x66) | |
149 | { | |
150 | codestream_get (); | |
151 | data16 = 1; | |
152 | } | |
28ee4b42 | 153 | |
bd5635a1 RP |
154 | switch (codestream_get ()) |
155 | { | |
156 | case 0xe9: | |
157 | /* relative jump: if data16 == 0, disp32, else disp16 */ | |
158 | if (data16) | |
159 | { | |
28ee4b42 PS |
160 | codestream_read (buf, 2); |
161 | delta = extract_signed_integer (buf, 2); | |
f2ebc25f JK |
162 | |
163 | /* include size of jmp inst (including the 0x66 prefix). */ | |
28ee4b42 | 164 | pos += delta + 4; |
bd5635a1 RP |
165 | } |
166 | else | |
167 | { | |
28ee4b42 PS |
168 | codestream_read (buf, 4); |
169 | delta = extract_signed_integer (buf, 4); | |
170 | ||
171 | pos += delta + 5; | |
bd5635a1 RP |
172 | } |
173 | break; | |
174 | case 0xeb: | |
175 | /* relative jump, disp8 (ignore data16) */ | |
28ee4b42 PS |
176 | codestream_read (buf, 1); |
177 | /* Sign-extend it. */ | |
178 | delta = extract_signed_integer (buf, 1); | |
179 | ||
180 | pos += delta + 2; | |
bd5635a1 RP |
181 | break; |
182 | } | |
f2ebc25f | 183 | codestream_seek (pos); |
bd5635a1 RP |
184 | } |
185 | ||
186 | /* | |
187 | * find & return amound a local space allocated, and advance codestream to | |
188 | * first register push (if any) | |
189 | * | |
190 | * if entry sequence doesn't make sense, return -1, and leave | |
191 | * codestream pointer random | |
192 | */ | |
d747e0af | 193 | |
bd5635a1 RP |
194 | static long |
195 | i386_get_frame_setup (pc) | |
f33b2c13 | 196 | CORE_ADDR pc; |
bd5635a1 RP |
197 | { |
198 | unsigned char op; | |
28ee4b42 | 199 | |
bd5635a1 | 200 | codestream_seek (pc); |
28ee4b42 | 201 | |
bd5635a1 | 202 | i386_follow_jump (); |
28ee4b42 | 203 | |
bd5635a1 | 204 | op = codestream_get (); |
28ee4b42 | 205 | |
bd5635a1 RP |
206 | if (op == 0x58) /* popl %eax */ |
207 | { | |
208 | /* | |
209 | * this function must start with | |
210 | * | |
211 | * popl %eax 0x58 | |
212 | * xchgl %eax, (%esp) 0x87 0x04 0x24 | |
213 | * or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00 | |
214 | * | |
215 | * (the system 5 compiler puts out the second xchg | |
216 | * inst, and the assembler doesn't try to optimize it, | |
217 | * so the 'sib' form gets generated) | |
218 | * | |
219 | * this sequence is used to get the address of the return | |
220 | * buffer for a function that returns a structure | |
221 | */ | |
222 | int pos; | |
223 | unsigned char buf[4]; | |
224 | static unsigned char proto1[3] = { 0x87,0x04,0x24 }; | |
225 | static unsigned char proto2[4] = { 0x87,0x44,0x24,0x00 }; | |
226 | pos = codestream_tell (); | |
227 | codestream_read (buf, 4); | |
51b57ded | 228 | if (memcmp (buf, proto1, 3) == 0) |
bd5635a1 | 229 | pos += 3; |
51b57ded | 230 | else if (memcmp (buf, proto2, 4) == 0) |
bd5635a1 | 231 | pos += 4; |
28ee4b42 | 232 | |
bd5635a1 RP |
233 | codestream_seek (pos); |
234 | op = codestream_get (); /* update next opcode */ | |
235 | } | |
28ee4b42 | 236 | |
c98fe0c1 JI |
237 | if (op == 0x68 || op == 0x6a) |
238 | { | |
239 | /* | |
240 | * this function may start with | |
241 | * | |
242 | * pushl constant | |
243 | * call _probe | |
244 | * addl $4, %esp | |
245 | * followed by | |
246 | * pushl %ebp | |
247 | * etc. | |
248 | */ | |
249 | int pos; | |
250 | unsigned char buf[8]; | |
251 | ||
252 | /* Skip past the pushl instruction; it has either a one-byte | |
253 | or a four-byte operand, depending on the opcode. */ | |
254 | pos = codestream_tell (); | |
255 | if (op == 0x68) | |
256 | pos += 4; | |
257 | else | |
258 | pos += 1; | |
259 | codestream_seek (pos); | |
260 | ||
261 | /* Read the following 8 bytes, which should be "call _probe" (6 bytes) | |
262 | followed by "addl $4,%esp" (2 bytes). */ | |
263 | codestream_read (buf, sizeof (buf)); | |
264 | if (buf[0] == 0xe8 && buf[6] == 0xc4 && buf[7] == 0x4) | |
265 | pos += sizeof (buf); | |
266 | codestream_seek (pos); | |
267 | op = codestream_get (); /* update next opcode */ | |
268 | } | |
269 | ||
bd5635a1 RP |
270 | if (op == 0x55) /* pushl %ebp */ |
271 | { | |
272 | /* check for movl %esp, %ebp - can be written two ways */ | |
273 | switch (codestream_get ()) | |
274 | { | |
275 | case 0x8b: | |
276 | if (codestream_get () != 0xec) | |
277 | return (-1); | |
278 | break; | |
279 | case 0x89: | |
280 | if (codestream_get () != 0xe5) | |
281 | return (-1); | |
282 | break; | |
283 | default: | |
284 | return (-1); | |
285 | } | |
286 | /* check for stack adjustment | |
287 | * | |
288 | * subl $XXX, %esp | |
289 | * | |
290 | * note: you can't subtract a 16 bit immediate | |
291 | * from a 32 bit reg, so we don't have to worry | |
292 | * about a data16 prefix | |
293 | */ | |
294 | op = codestream_peek (); | |
295 | if (op == 0x83) | |
296 | { | |
297 | /* subl with 8 bit immed */ | |
298 | codestream_get (); | |
299 | if (codestream_get () != 0xec) | |
300 | /* Some instruction starting with 0x83 other than subl. */ | |
301 | { | |
302 | codestream_seek (codestream_tell () - 2); | |
303 | return 0; | |
304 | } | |
305 | /* subl with signed byte immediate | |
306 | * (though it wouldn't make sense to be negative) | |
307 | */ | |
308 | return (codestream_get()); | |
309 | } | |
310 | else if (op == 0x81) | |
311 | { | |
34df79fc JK |
312 | char buf[4]; |
313 | /* Maybe it is subl with 32 bit immedediate. */ | |
bd5635a1 RP |
314 | codestream_get(); |
315 | if (codestream_get () != 0xec) | |
316 | /* Some instruction starting with 0x81 other than subl. */ | |
317 | { | |
318 | codestream_seek (codestream_tell () - 2); | |
319 | return 0; | |
320 | } | |
34df79fc JK |
321 | /* It is subl with 32 bit immediate. */ |
322 | codestream_read ((unsigned char *)buf, 4); | |
323 | return extract_signed_integer (buf, 4); | |
bd5635a1 RP |
324 | } |
325 | else | |
326 | { | |
327 | return (0); | |
328 | } | |
329 | } | |
330 | else if (op == 0xc8) | |
331 | { | |
34df79fc | 332 | char buf[2]; |
bd5635a1 | 333 | /* enter instruction: arg is 16 bit unsigned immed */ |
34df79fc | 334 | codestream_read ((unsigned char *)buf, 2); |
bd5635a1 | 335 | codestream_get (); /* flush final byte of enter instruction */ |
34df79fc | 336 | return extract_unsigned_integer (buf, 2); |
bd5635a1 RP |
337 | } |
338 | return (-1); | |
339 | } | |
340 | ||
341 | /* Return number of args passed to a frame. | |
342 | Can return -1, meaning no way to tell. */ | |
343 | ||
bd5635a1 RP |
344 | int |
345 | i386_frame_num_args (fi) | |
d747e0af | 346 | struct frame_info *fi; |
bd5635a1 | 347 | { |
34df79fc JK |
348 | #if 1 |
349 | return -1; | |
350 | #else | |
351 | /* This loses because not only might the compiler not be popping the | |
352 | args right after the function call, it might be popping args from both | |
353 | this call and a previous one, and we would say there are more args | |
354 | than there really are. */ | |
355 | ||
bd5635a1 RP |
356 | int retpc; |
357 | unsigned char op; | |
358 | struct frame_info *pfi; | |
359 | ||
34df79fc JK |
360 | /* on the 386, the instruction following the call could be: |
361 | popl %ecx - one arg | |
362 | addl $imm, %esp - imm/4 args; imm may be 8 or 32 bits | |
363 | anything else - zero args */ | |
364 | ||
bd5635a1 RP |
365 | int frameless; |
366 | ||
367 | FRAMELESS_FUNCTION_INVOCATION (fi, frameless); | |
368 | if (frameless) | |
369 | /* In the absence of a frame pointer, GDB doesn't get correct values | |
370 | for nameless arguments. Return -1, so it doesn't print any | |
371 | nameless arguments. */ | |
372 | return -1; | |
373 | ||
d747e0af | 374 | pfi = get_prev_frame_info (fi); |
bd5635a1 RP |
375 | if (pfi == 0) |
376 | { | |
377 | /* Note: this can happen if we are looking at the frame for | |
378 | main, because FRAME_CHAIN_VALID won't let us go into | |
379 | start. If we have debugging symbols, that's not really | |
380 | a big deal; it just means it will only show as many arguments | |
381 | to main as are declared. */ | |
382 | return -1; | |
383 | } | |
384 | else | |
385 | { | |
386 | retpc = pfi->pc; | |
387 | op = read_memory_integer (retpc, 1); | |
388 | if (op == 0x59) | |
389 | /* pop %ecx */ | |
390 | return 1; | |
391 | else if (op == 0x83) | |
392 | { | |
393 | op = read_memory_integer (retpc+1, 1); | |
394 | if (op == 0xc4) | |
395 | /* addl $<signed imm 8 bits>, %esp */ | |
396 | return (read_memory_integer (retpc+2,1)&0xff)/4; | |
397 | else | |
398 | return 0; | |
399 | } | |
400 | else if (op == 0x81) | |
401 | { /* add with 32 bit immediate */ | |
402 | op = read_memory_integer (retpc+1, 1); | |
403 | if (op == 0xc4) | |
404 | /* addl $<imm 32>, %esp */ | |
405 | return read_memory_integer (retpc+2, 4) / 4; | |
406 | else | |
407 | return 0; | |
408 | } | |
409 | else | |
410 | { | |
411 | return 0; | |
412 | } | |
413 | } | |
34df79fc | 414 | #endif |
bd5635a1 RP |
415 | } |
416 | ||
417 | /* | |
418 | * parse the first few instructions of the function to see | |
419 | * what registers were stored. | |
420 | * | |
421 | * We handle these cases: | |
422 | * | |
423 | * The startup sequence can be at the start of the function, | |
424 | * or the function can start with a branch to startup code at the end. | |
425 | * | |
426 | * %ebp can be set up with either the 'enter' instruction, or | |
427 | * 'pushl %ebp, movl %esp, %ebp' (enter is too slow to be useful, | |
428 | * but was once used in the sys5 compiler) | |
429 | * | |
430 | * Local space is allocated just below the saved %ebp by either the | |
431 | * 'enter' instruction, or by 'subl $<size>, %esp'. 'enter' has | |
432 | * a 16 bit unsigned argument for space to allocate, and the | |
433 | * 'addl' instruction could have either a signed byte, or | |
434 | * 32 bit immediate. | |
435 | * | |
436 | * Next, the registers used by this function are pushed. In | |
437 | * the sys5 compiler they will always be in the order: %edi, %esi, %ebx | |
438 | * (and sometimes a harmless bug causes it to also save but not restore %eax); | |
439 | * however, the code below is willing to see the pushes in any order, | |
440 | * and will handle up to 8 of them. | |
441 | * | |
442 | * If the setup sequence is at the end of the function, then the | |
443 | * next instruction will be a branch back to the start. | |
444 | */ | |
445 | ||
d747e0af | 446 | void |
bd5635a1 RP |
447 | i386_frame_find_saved_regs (fip, fsrp) |
448 | struct frame_info *fip; | |
449 | struct frame_saved_regs *fsrp; | |
450 | { | |
c98fe0c1 | 451 | long locals = -1; |
bd5635a1 RP |
452 | unsigned char op; |
453 | CORE_ADDR dummy_bottom; | |
454 | CORE_ADDR adr; | |
c98fe0c1 | 455 | CORE_ADDR pc; |
bd5635a1 RP |
456 | int i; |
457 | ||
34df79fc | 458 | memset (fsrp, 0, sizeof *fsrp); |
bd5635a1 RP |
459 | |
460 | /* if frame is the end of a dummy, compute where the | |
461 | * beginning would be | |
462 | */ | |
463 | dummy_bottom = fip->frame - 4 - REGISTER_BYTES - CALL_DUMMY_LENGTH; | |
464 | ||
465 | /* check if the PC is in the stack, in a dummy frame */ | |
466 | if (dummy_bottom <= fip->pc && fip->pc <= fip->frame) | |
467 | { | |
468 | /* all regs were saved by push_call_dummy () */ | |
469 | adr = fip->frame; | |
470 | for (i = 0; i < NUM_REGS; i++) | |
471 | { | |
472 | adr -= REGISTER_RAW_SIZE (i); | |
473 | fsrp->regs[i] = adr; | |
474 | } | |
475 | return; | |
476 | } | |
477 | ||
c98fe0c1 JI |
478 | pc = get_pc_function_start (fip->pc); |
479 | if (pc != 0) | |
480 | locals = i386_get_frame_setup (pc); | |
bd5635a1 RP |
481 | |
482 | if (locals >= 0) | |
483 | { | |
484 | adr = fip->frame - 4 - locals; | |
485 | for (i = 0; i < 8; i++) | |
486 | { | |
487 | op = codestream_get (); | |
488 | if (op < 0x50 || op > 0x57) | |
489 | break; | |
1a494973 C |
490 | #ifdef I386_REGNO_TO_SYMMETRY |
491 | /* Dynix uses different internal numbering. Ick. */ | |
492 | fsrp->regs[I386_REGNO_TO_SYMMETRY(op - 0x50)] = adr; | |
493 | #else | |
bd5635a1 | 494 | fsrp->regs[op - 0x50] = adr; |
1a494973 | 495 | #endif |
bd5635a1 RP |
496 | adr -= 4; |
497 | } | |
498 | } | |
499 | ||
500 | fsrp->regs[PC_REGNUM] = fip->frame + 4; | |
501 | fsrp->regs[FP_REGNUM] = fip->frame; | |
502 | } | |
503 | ||
504 | /* return pc of first real instruction */ | |
d747e0af MT |
505 | |
506 | int | |
bd5635a1 | 507 | i386_skip_prologue (pc) |
d747e0af | 508 | int pc; |
bd5635a1 RP |
509 | { |
510 | unsigned char op; | |
511 | int i; | |
28ee4b42 PS |
512 | static unsigned char pic_pat[6] = { 0xe8, 0, 0, 0, 0, /* call 0x0 */ |
513 | 0x5b, /* popl %ebx */ | |
514 | }; | |
515 | CORE_ADDR pos; | |
bd5635a1 RP |
516 | |
517 | if (i386_get_frame_setup (pc) < 0) | |
518 | return (pc); | |
519 | ||
520 | /* found valid frame setup - codestream now points to | |
521 | * start of push instructions for saving registers | |
522 | */ | |
523 | ||
524 | /* skip over register saves */ | |
525 | for (i = 0; i < 8; i++) | |
526 | { | |
527 | op = codestream_peek (); | |
528 | /* break if not pushl inst */ | |
529 | if (op < 0x50 || op > 0x57) | |
530 | break; | |
531 | codestream_get (); | |
532 | } | |
28ee4b42 PS |
533 | |
534 | /* The native cc on SVR4 in -K PIC mode inserts the following code to get | |
535 | the address of the global offset table (GOT) into register %ebx. | |
536 | call 0x0 | |
537 | popl %ebx | |
538 | movl %ebx,x(%ebp) (optional) | |
539 | addl y,%ebx | |
540 | This code is with the rest of the prologue (at the end of the | |
541 | function), so we have to skip it to get to the first real | |
542 | instruction at the start of the function. */ | |
543 | ||
544 | pos = codestream_tell (); | |
545 | for (i = 0; i < 6; i++) | |
546 | { | |
547 | op = codestream_get (); | |
548 | if (pic_pat [i] != op) | |
549 | break; | |
550 | } | |
551 | if (i == 6) | |
552 | { | |
553 | unsigned char buf[4]; | |
554 | long delta = 6; | |
555 | ||
556 | op = codestream_get (); | |
557 | if (op == 0x89) /* movl %ebx, x(%ebp) */ | |
558 | { | |
559 | op = codestream_get (); | |
560 | if (op == 0x5d) /* one byte offset from %ebp */ | |
561 | { | |
562 | delta += 3; | |
563 | codestream_read (buf, 1); | |
564 | } | |
565 | else if (op == 0x9d) /* four byte offset from %ebp */ | |
566 | { | |
567 | delta += 6; | |
568 | codestream_read (buf, 4); | |
569 | } | |
570 | else /* unexpected instruction */ | |
571 | delta = -1; | |
572 | op = codestream_get (); | |
573 | } | |
574 | /* addl y,%ebx */ | |
575 | if (delta > 0 && op == 0x81 && codestream_get () == 0xc3) | |
576 | { | |
577 | pos += delta + 6; | |
578 | } | |
579 | } | |
580 | codestream_seek (pos); | |
bd5635a1 RP |
581 | |
582 | i386_follow_jump (); | |
583 | ||
584 | return (codestream_tell ()); | |
585 | } | |
586 | ||
d747e0af | 587 | void |
bd5635a1 RP |
588 | i386_push_dummy_frame () |
589 | { | |
590 | CORE_ADDR sp = read_register (SP_REGNUM); | |
591 | int regnum; | |
592 | char regbuf[MAX_REGISTER_RAW_SIZE]; | |
593 | ||
594 | sp = push_word (sp, read_register (PC_REGNUM)); | |
595 | sp = push_word (sp, read_register (FP_REGNUM)); | |
596 | write_register (FP_REGNUM, sp); | |
597 | for (regnum = 0; regnum < NUM_REGS; regnum++) | |
598 | { | |
599 | read_register_gen (regnum, regbuf); | |
600 | sp = push_bytes (sp, regbuf, REGISTER_RAW_SIZE (regnum)); | |
601 | } | |
602 | write_register (SP_REGNUM, sp); | |
603 | } | |
604 | ||
d747e0af | 605 | void |
bd5635a1 RP |
606 | i386_pop_frame () |
607 | { | |
1a494973 | 608 | struct frame_info *frame = get_current_frame (); |
bd5635a1 RP |
609 | CORE_ADDR fp; |
610 | int regnum; | |
611 | struct frame_saved_regs fsr; | |
bd5635a1 RP |
612 | char regbuf[MAX_REGISTER_RAW_SIZE]; |
613 | ||
1a494973 C |
614 | fp = FRAME_FP (frame); |
615 | get_frame_saved_regs (frame, &fsr); | |
bd5635a1 RP |
616 | for (regnum = 0; regnum < NUM_REGS; regnum++) |
617 | { | |
618 | CORE_ADDR adr; | |
619 | adr = fsr.regs[regnum]; | |
620 | if (adr) | |
621 | { | |
622 | read_memory (adr, regbuf, REGISTER_RAW_SIZE (regnum)); | |
623 | write_register_bytes (REGISTER_BYTE (regnum), regbuf, | |
624 | REGISTER_RAW_SIZE (regnum)); | |
625 | } | |
626 | } | |
627 | write_register (FP_REGNUM, read_memory_integer (fp, 4)); | |
628 | write_register (PC_REGNUM, read_memory_integer (fp + 4, 4)); | |
629 | write_register (SP_REGNUM, fp + 8); | |
630 | flush_cached_frames (); | |
bd5635a1 | 631 | } |
d747e0af | 632 | |
51b57ded FF |
633 | #ifdef GET_LONGJMP_TARGET |
634 | ||
635 | /* Figure out where the longjmp will land. Slurp the args out of the stack. | |
636 | We expect the first arg to be a pointer to the jmp_buf structure from which | |
637 | we extract the pc (JB_PC) that we will land at. The pc is copied into PC. | |
638 | This routine returns true on success. */ | |
639 | ||
640 | int | |
641 | get_longjmp_target(pc) | |
642 | CORE_ADDR *pc; | |
643 | { | |
34df79fc | 644 | char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT]; |
51b57ded FF |
645 | CORE_ADDR sp, jb_addr; |
646 | ||
34df79fc | 647 | sp = read_register (SP_REGNUM); |
51b57ded | 648 | |
34df79fc JK |
649 | if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack */ |
650 | buf, | |
651 | TARGET_PTR_BIT / TARGET_CHAR_BIT)) | |
51b57ded FF |
652 | return 0; |
653 | ||
34df79fc | 654 | jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); |
51b57ded | 655 | |
34df79fc JK |
656 | if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf, |
657 | TARGET_PTR_BIT / TARGET_CHAR_BIT)) | |
51b57ded FF |
658 | return 0; |
659 | ||
34df79fc | 660 | *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); |
51b57ded FF |
661 | |
662 | return 1; | |
663 | } | |
664 | ||
665 | #endif /* GET_LONGJMP_TARGET */ | |
34df79fc | 666 | |
34df79fc JK |
667 | void |
668 | i386_extract_return_value(type, regbuf, valbuf) | |
669 | struct type *type; | |
670 | char regbuf[REGISTER_BYTES]; | |
671 | char *valbuf; | |
672 | { | |
f33b2c13 SG |
673 | /* On AIX, floating point values are returned in floating point registers. */ |
674 | #ifdef I386_AIX_TARGET | |
34df79fc JK |
675 | if (TYPE_CODE_FLT == TYPE_CODE(type)) |
676 | { | |
34df79fc JK |
677 | double d; |
678 | /* 387 %st(0), gcc uses this */ | |
eae3f093 JK |
679 | floatformat_to_double (&floatformat_i387_ext, |
680 | ®buf[REGISTER_BYTE(FP0_REGNUM)], | |
681 | &d); | |
28ee4b42 | 682 | store_floating (valbuf, TYPE_LENGTH (type), d); |
34df79fc JK |
683 | } |
684 | else | |
f33b2c13 | 685 | #endif /* I386_AIX_TARGET */ |
34df79fc JK |
686 | { |
687 | memcpy (valbuf, regbuf, TYPE_LENGTH (type)); | |
688 | } | |
689 | } | |
28ee4b42 PS |
690 | |
691 | #ifdef I386V4_SIGTRAMP_SAVED_PC | |
692 | /* Get saved user PC for sigtramp from the pushed ucontext on the stack | |
693 | for all three variants of SVR4 sigtramps. */ | |
694 | ||
695 | CORE_ADDR | |
696 | i386v4_sigtramp_saved_pc (frame) | |
1a494973 | 697 | struct frame_info *frame; |
28ee4b42 PS |
698 | { |
699 | CORE_ADDR saved_pc_offset = 4; | |
700 | char *name = NULL; | |
701 | ||
1a494973 | 702 | find_pc_partial_function (frame->pc, &name, NULL, NULL); |
28ee4b42 PS |
703 | if (name) |
704 | { | |
705 | if (STREQ (name, "_sigreturn")) | |
706 | saved_pc_offset = 132 + 14 * 4; | |
137b6849 | 707 | else if (STREQ (name, "_sigacthandler")) |
28ee4b42 | 708 | saved_pc_offset = 80 + 14 * 4; |
137b6849 | 709 | else if (STREQ (name, "sigvechandler")) |
28ee4b42 PS |
710 | saved_pc_offset = 120 + 14 * 4; |
711 | } | |
712 | ||
713 | if (frame->next) | |
714 | return read_memory_integer (frame->next->frame + saved_pc_offset, 4); | |
715 | return read_memory_integer (read_register (SP_REGNUM) + saved_pc_offset, 4); | |
716 | } | |
717 | #endif /* I386V4_SIGTRAMP_SAVED_PC */ | |
1a494973 | 718 | |
c98fe0c1 JI |
719 | #ifdef STATIC_TRANSFORM_NAME |
720 | /* SunPRO encodes the static variables. This is not related to C++ mangling, | |
721 | it is done for C too. */ | |
722 | ||
723 | char * | |
724 | sunpro_static_transform_name (name) | |
725 | char *name; | |
726 | { | |
727 | char *p; | |
728 | if (IS_STATIC_TRANSFORM_NAME (name)) | |
729 | { | |
730 | /* For file-local statics there will be a period, a bunch | |
731 | of junk (the contents of which match a string given in the | |
732 | N_OPT), a period and the name. For function-local statics | |
733 | there will be a bunch of junk (which seems to change the | |
734 | second character from 'A' to 'B'), a period, the name of the | |
735 | function, and the name. So just skip everything before the | |
736 | last period. */ | |
737 | p = strrchr (name, '.'); | |
738 | if (p != NULL) | |
739 | name = p + 1; | |
740 | } | |
741 | return name; | |
742 | } | |
743 | #endif /* STATIC_TRANSFORM_NAME */ | |
744 | ||
f33b2c13 SG |
745 | |
746 | ||
747 | /* Stuff for WIN32 PE style DLL's but is pretty generic really. */ | |
748 | ||
749 | CORE_ADDR | |
750 | skip_trampoline_code (pc, name) | |
751 | CORE_ADDR pc; | |
752 | char *name; | |
753 | { | |
754 | if (pc && read_memory_unsigned_integer (pc, 2) == 0x25ff) /* jmp *(dest) */ | |
755 | { | |
756 | unsigned long indirect = read_memory_unsigned_integer (pc+2, 4); | |
757 | struct minimal_symbol *indsym = | |
758 | indirect ? lookup_minimal_symbol_by_pc (indirect) : 0; | |
759 | char *symname = indsym ? SYMBOL_NAME(indsym) : 0; | |
760 | ||
761 | if (symname) | |
762 | { | |
763 | if (strncmp (symname,"__imp_", 6) == 0 | |
764 | || strncmp (symname,"_imp_", 5) == 0) | |
765 | return name ? 1 : read_memory_unsigned_integer (indirect, 4); | |
766 | } | |
767 | } | |
768 | return 0; /* not a trampoline */ | |
769 | } | |
770 | ||
c98fe0c1 JI |
771 | static int |
772 | gdb_print_insn_i386 (memaddr, info) | |
773 | bfd_vma memaddr; | |
774 | disassemble_info * info; | |
f33b2c13 | 775 | { |
c98fe0c1 JI |
776 | if (disassembly_flavor == att_flavor) |
777 | print_insn_i386_att (memaddr, info); | |
778 | else if (disassembly_flavor == intel_flavor) | |
779 | print_insn_i386_intel (memaddr, info); | |
780 | ||
f33b2c13 SG |
781 | } |
782 | ||
1a494973 C |
783 | void |
784 | _initialize_i386_tdep () | |
785 | { | |
c98fe0c1 JI |
786 | tm_print_insn = gdb_print_insn_i386; |
787 | tm_print_insn_info.mach = bfd_lookup_arch (bfd_arch_i386, 0)->mach; | |
788 | ||
789 | /* Add the variable that controls the disassembly flavor */ | |
790 | add_show_from_set( | |
791 | add_set_enum_cmd ("disassembly-flavor", no_class, | |
792 | valid_flavors, | |
793 | (char *) &disassembly_flavor, | |
794 | "Set the disassembly flavor, the valid values are \"att\" and \"intel\", \ | |
795 | and the default value is \"att\".", | |
796 | &setlist), | |
797 | &showlist); | |
f33b2c13 | 798 | |
c98fe0c1 | 799 | |
1a494973 | 800 | } |