]>
Commit | Line | Data |
---|---|---|
c906108c SS |
1 | /* Intel 386 target-dependent stuff. |
2 | Copyright (C) 1988, 1989, 1991, 1994, 1995, 1996, 1998 | |
3 | Free Software Foundation, Inc. | |
4 | ||
c5aa993b | 5 | This file is part of GDB. |
c906108c | 6 | |
c5aa993b JM |
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 2 of the License, or | |
10 | (at your option) any later version. | |
c906108c | 11 | |
c5aa993b JM |
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. | |
c906108c | 16 | |
c5aa993b JM |
17 | You should have received a copy of the GNU General Public License |
18 | along with this program; if not, write to the Free Software | |
19 | Foundation, Inc., 59 Temple Place - Suite 330, | |
20 | Boston, MA 02111-1307, USA. */ | |
c906108c SS |
21 | |
22 | #include "defs.h" | |
23 | #include "gdb_string.h" | |
24 | #include "frame.h" | |
25 | #include "inferior.h" | |
26 | #include "gdbcore.h" | |
27 | #include "target.h" | |
28 | #include "floatformat.h" | |
29 | #include "symtab.h" | |
30 | #include "gdbcmd.h" | |
31 | #include "command.h" | |
32 | ||
a14ed312 | 33 | static long i386_get_frame_setup (CORE_ADDR); |
c906108c | 34 | |
a14ed312 | 35 | static void i386_follow_jump (void); |
c906108c | 36 | |
a14ed312 | 37 | static void codestream_read (unsigned char *, int); |
c906108c | 38 | |
a14ed312 | 39 | static void codestream_seek (CORE_ADDR); |
c906108c | 40 | |
a14ed312 | 41 | static unsigned char codestream_fill (int); |
c906108c | 42 | |
a14ed312 | 43 | CORE_ADDR skip_trampoline_code (CORE_ADDR, char *); |
c906108c SS |
44 | |
45 | static int gdb_print_insn_i386 (bfd_vma, disassemble_info *); | |
46 | ||
a14ed312 | 47 | void _initialize_i386_tdep (void); |
c906108c | 48 | |
917317f4 JM |
49 | /* i386_register_byte[i] is the offset into the register file of the |
50 | start of register number i. We initialize this from | |
51 | i386_register_raw_size. */ | |
52 | int i386_register_byte[MAX_NUM_REGS]; | |
53 | ||
ceb4951f JB |
54 | /* i386_register_raw_size[i] is the number of bytes of storage in |
55 | GDB's register array occupied by register i. */ | |
917317f4 JM |
56 | int i386_register_raw_size[MAX_NUM_REGS] = { |
57 | 4, 4, 4, 4, | |
58 | 4, 4, 4, 4, | |
59 | 4, 4, 4, 4, | |
60 | 4, 4, 4, 4, | |
61 | 10, 10, 10, 10, | |
62 | 10, 10, 10, 10, | |
63 | 4, 4, 4, 4, | |
64 | 4, 4, 4, 4, | |
65 | 16, 16, 16, 16, | |
66 | 16, 16, 16, 16, | |
67 | 4 | |
68 | }; | |
69 | ||
70 | /* i386_register_virtual_size[i] is the size in bytes of the virtual | |
71 | type of register i. */ | |
72 | int i386_register_virtual_size[MAX_NUM_REGS]; | |
73 | ||
74 | ||
c906108c | 75 | /* This is the variable the is set with "set disassembly-flavor", |
c5aa993b | 76 | and its legitimate values. */ |
c906108c SS |
77 | static char att_flavor[] = "att"; |
78 | static char intel_flavor[] = "intel"; | |
c5aa993b JM |
79 | static char *valid_flavors[] = |
80 | { | |
c906108c SS |
81 | att_flavor, |
82 | intel_flavor, | |
83 | NULL | |
84 | }; | |
85 | static char *disassembly_flavor = att_flavor; | |
86 | ||
a14ed312 | 87 | static void i386_print_register (char *, int, int); |
d4f3574e | 88 | |
7a292a7a | 89 | /* This is used to keep the bfd arch_info in sync with the disassembly flavor. */ |
a14ed312 KB |
90 | static void set_disassembly_flavor_sfunc (char *, int, |
91 | struct cmd_list_element *); | |
92 | static void set_disassembly_flavor (void); | |
7a292a7a | 93 | |
c906108c SS |
94 | /* Stdio style buffering was used to minimize calls to ptrace, but this |
95 | buffering did not take into account that the code section being accessed | |
96 | may not be an even number of buffers long (even if the buffer is only | |
97 | sizeof(int) long). In cases where the code section size happened to | |
98 | be a non-integral number of buffers long, attempting to read the last | |
99 | buffer would fail. Simply using target_read_memory and ignoring errors, | |
100 | rather than read_memory, is not the correct solution, since legitimate | |
101 | access errors would then be totally ignored. To properly handle this | |
102 | situation and continue to use buffering would require that this code | |
103 | be able to determine the minimum code section size granularity (not the | |
104 | alignment of the section itself, since the actual failing case that | |
105 | pointed out this problem had a section alignment of 4 but was not a | |
106 | multiple of 4 bytes long), on a target by target basis, and then | |
107 | adjust it's buffer size accordingly. This is messy, but potentially | |
108 | feasible. It probably needs the bfd library's help and support. For | |
109 | now, the buffer size is set to 1. (FIXME -fnf) */ | |
110 | ||
111 | #define CODESTREAM_BUFSIZ 1 /* Was sizeof(int), see note above. */ | |
112 | static CORE_ADDR codestream_next_addr; | |
113 | static CORE_ADDR codestream_addr; | |
114 | static unsigned char codestream_buf[CODESTREAM_BUFSIZ]; | |
115 | static int codestream_off; | |
116 | static int codestream_cnt; | |
117 | ||
118 | #define codestream_tell() (codestream_addr + codestream_off) | |
119 | #define codestream_peek() (codestream_cnt == 0 ? \ | |
120 | codestream_fill(1): codestream_buf[codestream_off]) | |
121 | #define codestream_get() (codestream_cnt-- == 0 ? \ | |
122 | codestream_fill(0) : codestream_buf[codestream_off++]) | |
123 | ||
c5aa993b | 124 | static unsigned char |
c906108c | 125 | codestream_fill (peek_flag) |
c5aa993b | 126 | int peek_flag; |
c906108c SS |
127 | { |
128 | codestream_addr = codestream_next_addr; | |
129 | codestream_next_addr += CODESTREAM_BUFSIZ; | |
130 | codestream_off = 0; | |
131 | codestream_cnt = CODESTREAM_BUFSIZ; | |
132 | read_memory (codestream_addr, (char *) codestream_buf, CODESTREAM_BUFSIZ); | |
c5aa993b | 133 | |
c906108c | 134 | if (peek_flag) |
c5aa993b | 135 | return (codestream_peek ()); |
c906108c | 136 | else |
c5aa993b | 137 | return (codestream_get ()); |
c906108c SS |
138 | } |
139 | ||
140 | static void | |
141 | codestream_seek (place) | |
c5aa993b | 142 | CORE_ADDR place; |
c906108c SS |
143 | { |
144 | codestream_next_addr = place / CODESTREAM_BUFSIZ; | |
145 | codestream_next_addr *= CODESTREAM_BUFSIZ; | |
146 | codestream_cnt = 0; | |
147 | codestream_fill (1); | |
c5aa993b | 148 | while (codestream_tell () != place) |
c906108c SS |
149 | codestream_get (); |
150 | } | |
151 | ||
152 | static void | |
153 | codestream_read (buf, count) | |
154 | unsigned char *buf; | |
155 | int count; | |
156 | { | |
157 | unsigned char *p; | |
158 | int i; | |
159 | p = buf; | |
160 | for (i = 0; i < count; i++) | |
161 | *p++ = codestream_get (); | |
162 | } | |
163 | ||
164 | /* next instruction is a jump, move to target */ | |
165 | ||
166 | static void | |
167 | i386_follow_jump () | |
168 | { | |
169 | unsigned char buf[4]; | |
170 | long delta; | |
171 | ||
172 | int data16; | |
173 | CORE_ADDR pos; | |
174 | ||
175 | pos = codestream_tell (); | |
176 | ||
177 | data16 = 0; | |
178 | if (codestream_peek () == 0x66) | |
179 | { | |
180 | codestream_get (); | |
181 | data16 = 1; | |
182 | } | |
183 | ||
184 | switch (codestream_get ()) | |
185 | { | |
186 | case 0xe9: | |
187 | /* relative jump: if data16 == 0, disp32, else disp16 */ | |
188 | if (data16) | |
189 | { | |
190 | codestream_read (buf, 2); | |
191 | delta = extract_signed_integer (buf, 2); | |
192 | ||
193 | /* include size of jmp inst (including the 0x66 prefix). */ | |
c5aa993b | 194 | pos += delta + 4; |
c906108c SS |
195 | } |
196 | else | |
197 | { | |
198 | codestream_read (buf, 4); | |
199 | delta = extract_signed_integer (buf, 4); | |
200 | ||
201 | pos += delta + 5; | |
202 | } | |
203 | break; | |
204 | case 0xeb: | |
205 | /* relative jump, disp8 (ignore data16) */ | |
206 | codestream_read (buf, 1); | |
207 | /* Sign-extend it. */ | |
208 | delta = extract_signed_integer (buf, 1); | |
209 | ||
210 | pos += delta + 2; | |
211 | break; | |
212 | } | |
213 | codestream_seek (pos); | |
214 | } | |
215 | ||
216 | /* | |
217 | * find & return amound a local space allocated, and advance codestream to | |
218 | * first register push (if any) | |
219 | * | |
220 | * if entry sequence doesn't make sense, return -1, and leave | |
221 | * codestream pointer random | |
222 | */ | |
223 | ||
224 | static long | |
225 | i386_get_frame_setup (pc) | |
226 | CORE_ADDR pc; | |
227 | { | |
228 | unsigned char op; | |
229 | ||
230 | codestream_seek (pc); | |
231 | ||
232 | i386_follow_jump (); | |
233 | ||
234 | op = codestream_get (); | |
235 | ||
236 | if (op == 0x58) /* popl %eax */ | |
237 | { | |
238 | /* | |
239 | * this function must start with | |
240 | * | |
c5aa993b | 241 | * popl %eax 0x58 |
c906108c SS |
242 | * xchgl %eax, (%esp) 0x87 0x04 0x24 |
243 | * or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00 | |
244 | * | |
245 | * (the system 5 compiler puts out the second xchg | |
246 | * inst, and the assembler doesn't try to optimize it, | |
247 | * so the 'sib' form gets generated) | |
248 | * | |
249 | * this sequence is used to get the address of the return | |
250 | * buffer for a function that returns a structure | |
251 | */ | |
252 | int pos; | |
253 | unsigned char buf[4]; | |
c5aa993b JM |
254 | static unsigned char proto1[3] = |
255 | {0x87, 0x04, 0x24}; | |
256 | static unsigned char proto2[4] = | |
257 | {0x87, 0x44, 0x24, 0x00}; | |
c906108c SS |
258 | pos = codestream_tell (); |
259 | codestream_read (buf, 4); | |
260 | if (memcmp (buf, proto1, 3) == 0) | |
261 | pos += 3; | |
262 | else if (memcmp (buf, proto2, 4) == 0) | |
263 | pos += 4; | |
264 | ||
265 | codestream_seek (pos); | |
c5aa993b | 266 | op = codestream_get (); /* update next opcode */ |
c906108c SS |
267 | } |
268 | ||
269 | if (op == 0x68 || op == 0x6a) | |
270 | { | |
271 | /* | |
272 | * this function may start with | |
273 | * | |
274 | * pushl constant | |
275 | * call _probe | |
276 | * addl $4, %esp | |
277 | * followed by | |
278 | * pushl %ebp | |
279 | * etc. | |
280 | */ | |
281 | int pos; | |
282 | unsigned char buf[8]; | |
283 | ||
284 | /* Skip past the pushl instruction; it has either a one-byte | |
285 | or a four-byte operand, depending on the opcode. */ | |
286 | pos = codestream_tell (); | |
287 | if (op == 0x68) | |
288 | pos += 4; | |
289 | else | |
290 | pos += 1; | |
291 | codestream_seek (pos); | |
292 | ||
293 | /* Read the following 8 bytes, which should be "call _probe" (6 bytes) | |
294 | followed by "addl $4,%esp" (2 bytes). */ | |
295 | codestream_read (buf, sizeof (buf)); | |
296 | if (buf[0] == 0xe8 && buf[6] == 0xc4 && buf[7] == 0x4) | |
297 | pos += sizeof (buf); | |
298 | codestream_seek (pos); | |
c5aa993b | 299 | op = codestream_get (); /* update next opcode */ |
c906108c SS |
300 | } |
301 | ||
302 | if (op == 0x55) /* pushl %ebp */ | |
c5aa993b | 303 | { |
c906108c SS |
304 | /* check for movl %esp, %ebp - can be written two ways */ |
305 | switch (codestream_get ()) | |
306 | { | |
307 | case 0x8b: | |
308 | if (codestream_get () != 0xec) | |
309 | return (-1); | |
310 | break; | |
311 | case 0x89: | |
312 | if (codestream_get () != 0xe5) | |
313 | return (-1); | |
314 | break; | |
315 | default: | |
316 | return (-1); | |
317 | } | |
318 | /* check for stack adjustment | |
c5aa993b | 319 | |
c906108c SS |
320 | * subl $XXX, %esp |
321 | * | |
322 | * note: you can't subtract a 16 bit immediate | |
323 | * from a 32 bit reg, so we don't have to worry | |
324 | * about a data16 prefix | |
325 | */ | |
326 | op = codestream_peek (); | |
327 | if (op == 0x83) | |
328 | { | |
329 | /* subl with 8 bit immed */ | |
330 | codestream_get (); | |
331 | if (codestream_get () != 0xec) | |
332 | /* Some instruction starting with 0x83 other than subl. */ | |
333 | { | |
334 | codestream_seek (codestream_tell () - 2); | |
335 | return 0; | |
336 | } | |
337 | /* subl with signed byte immediate | |
338 | * (though it wouldn't make sense to be negative) | |
339 | */ | |
c5aa993b | 340 | return (codestream_get ()); |
c906108c SS |
341 | } |
342 | else if (op == 0x81) | |
343 | { | |
344 | char buf[4]; | |
345 | /* Maybe it is subl with 32 bit immedediate. */ | |
c5aa993b | 346 | codestream_get (); |
c906108c SS |
347 | if (codestream_get () != 0xec) |
348 | /* Some instruction starting with 0x81 other than subl. */ | |
349 | { | |
350 | codestream_seek (codestream_tell () - 2); | |
351 | return 0; | |
352 | } | |
353 | /* It is subl with 32 bit immediate. */ | |
c5aa993b | 354 | codestream_read ((unsigned char *) buf, 4); |
c906108c SS |
355 | return extract_signed_integer (buf, 4); |
356 | } | |
357 | else | |
358 | { | |
359 | return (0); | |
360 | } | |
361 | } | |
362 | else if (op == 0xc8) | |
363 | { | |
364 | char buf[2]; | |
365 | /* enter instruction: arg is 16 bit unsigned immed */ | |
c5aa993b JM |
366 | codestream_read ((unsigned char *) buf, 2); |
367 | codestream_get (); /* flush final byte of enter instruction */ | |
c906108c SS |
368 | return extract_unsigned_integer (buf, 2); |
369 | } | |
370 | return (-1); | |
371 | } | |
372 | ||
373 | /* Return number of args passed to a frame. | |
374 | Can return -1, meaning no way to tell. */ | |
375 | ||
376 | int | |
377 | i386_frame_num_args (fi) | |
378 | struct frame_info *fi; | |
379 | { | |
380 | #if 1 | |
381 | return -1; | |
382 | #else | |
383 | /* This loses because not only might the compiler not be popping the | |
384 | args right after the function call, it might be popping args from both | |
385 | this call and a previous one, and we would say there are more args | |
386 | than there really are. */ | |
387 | ||
c5aa993b JM |
388 | int retpc; |
389 | unsigned char op; | |
c906108c SS |
390 | struct frame_info *pfi; |
391 | ||
392 | /* on the 386, the instruction following the call could be: | |
393 | popl %ecx - one arg | |
394 | addl $imm, %esp - imm/4 args; imm may be 8 or 32 bits | |
395 | anything else - zero args */ | |
396 | ||
397 | int frameless; | |
398 | ||
392a587b | 399 | frameless = FRAMELESS_FUNCTION_INVOCATION (fi); |
c906108c SS |
400 | if (frameless) |
401 | /* In the absence of a frame pointer, GDB doesn't get correct values | |
402 | for nameless arguments. Return -1, so it doesn't print any | |
403 | nameless arguments. */ | |
404 | return -1; | |
405 | ||
c5aa993b | 406 | pfi = get_prev_frame (fi); |
c906108c SS |
407 | if (pfi == 0) |
408 | { | |
409 | /* Note: this can happen if we are looking at the frame for | |
c5aa993b JM |
410 | main, because FRAME_CHAIN_VALID won't let us go into |
411 | start. If we have debugging symbols, that's not really | |
412 | a big deal; it just means it will only show as many arguments | |
413 | to main as are declared. */ | |
c906108c SS |
414 | return -1; |
415 | } | |
416 | else | |
417 | { | |
c5aa993b JM |
418 | retpc = pfi->pc; |
419 | op = read_memory_integer (retpc, 1); | |
420 | if (op == 0x59) | |
421 | /* pop %ecx */ | |
422 | return 1; | |
c906108c SS |
423 | else if (op == 0x83) |
424 | { | |
c5aa993b JM |
425 | op = read_memory_integer (retpc + 1, 1); |
426 | if (op == 0xc4) | |
427 | /* addl $<signed imm 8 bits>, %esp */ | |
428 | return (read_memory_integer (retpc + 2, 1) & 0xff) / 4; | |
c906108c SS |
429 | else |
430 | return 0; | |
431 | } | |
432 | else if (op == 0x81) | |
c5aa993b JM |
433 | { /* add with 32 bit immediate */ |
434 | op = read_memory_integer (retpc + 1, 1); | |
435 | if (op == 0xc4) | |
436 | /* addl $<imm 32>, %esp */ | |
437 | return read_memory_integer (retpc + 2, 4) / 4; | |
c906108c SS |
438 | else |
439 | return 0; | |
440 | } | |
441 | else | |
442 | { | |
443 | return 0; | |
444 | } | |
445 | } | |
446 | #endif | |
447 | } | |
448 | ||
449 | /* | |
450 | * parse the first few instructions of the function to see | |
451 | * what registers were stored. | |
452 | * | |
453 | * We handle these cases: | |
454 | * | |
455 | * The startup sequence can be at the start of the function, | |
456 | * or the function can start with a branch to startup code at the end. | |
457 | * | |
458 | * %ebp can be set up with either the 'enter' instruction, or | |
459 | * 'pushl %ebp, movl %esp, %ebp' (enter is too slow to be useful, | |
460 | * but was once used in the sys5 compiler) | |
461 | * | |
462 | * Local space is allocated just below the saved %ebp by either the | |
463 | * 'enter' instruction, or by 'subl $<size>, %esp'. 'enter' has | |
464 | * a 16 bit unsigned argument for space to allocate, and the | |
465 | * 'addl' instruction could have either a signed byte, or | |
466 | * 32 bit immediate. | |
467 | * | |
468 | * Next, the registers used by this function are pushed. In | |
469 | * the sys5 compiler they will always be in the order: %edi, %esi, %ebx | |
470 | * (and sometimes a harmless bug causes it to also save but not restore %eax); | |
471 | * however, the code below is willing to see the pushes in any order, | |
472 | * and will handle up to 8 of them. | |
473 | * | |
474 | * If the setup sequence is at the end of the function, then the | |
475 | * next instruction will be a branch back to the start. | |
476 | */ | |
477 | ||
478 | void | |
1211c4e4 | 479 | i386_frame_init_saved_regs (fip) |
c906108c | 480 | struct frame_info *fip; |
c906108c SS |
481 | { |
482 | long locals = -1; | |
483 | unsigned char op; | |
484 | CORE_ADDR dummy_bottom; | |
485 | CORE_ADDR adr; | |
486 | CORE_ADDR pc; | |
487 | int i; | |
c5aa993b | 488 | |
1211c4e4 AC |
489 | if (fip->saved_regs) |
490 | return; | |
491 | ||
492 | frame_saved_regs_zalloc (fip); | |
c5aa993b | 493 | |
c906108c SS |
494 | /* if frame is the end of a dummy, compute where the |
495 | * beginning would be | |
496 | */ | |
497 | dummy_bottom = fip->frame - 4 - REGISTER_BYTES - CALL_DUMMY_LENGTH; | |
c5aa993b | 498 | |
c906108c | 499 | /* check if the PC is in the stack, in a dummy frame */ |
c5aa993b | 500 | if (dummy_bottom <= fip->pc && fip->pc <= fip->frame) |
c906108c SS |
501 | { |
502 | /* all regs were saved by push_call_dummy () */ | |
503 | adr = fip->frame; | |
c5aa993b | 504 | for (i = 0; i < NUM_REGS; i++) |
c906108c SS |
505 | { |
506 | adr -= REGISTER_RAW_SIZE (i); | |
1211c4e4 | 507 | fip->saved_regs[i] = adr; |
c906108c SS |
508 | } |
509 | return; | |
510 | } | |
c5aa993b | 511 | |
c906108c SS |
512 | pc = get_pc_function_start (fip->pc); |
513 | if (pc != 0) | |
514 | locals = i386_get_frame_setup (pc); | |
c5aa993b JM |
515 | |
516 | if (locals >= 0) | |
c906108c SS |
517 | { |
518 | adr = fip->frame - 4 - locals; | |
c5aa993b | 519 | for (i = 0; i < 8; i++) |
c906108c SS |
520 | { |
521 | op = codestream_get (); | |
522 | if (op < 0x50 || op > 0x57) | |
523 | break; | |
524 | #ifdef I386_REGNO_TO_SYMMETRY | |
525 | /* Dynix uses different internal numbering. Ick. */ | |
1211c4e4 | 526 | fip->saved_regs[I386_REGNO_TO_SYMMETRY (op - 0x50)] = adr; |
c906108c | 527 | #else |
1211c4e4 | 528 | fip->saved_regs[op - 0x50] = adr; |
c906108c SS |
529 | #endif |
530 | adr -= 4; | |
531 | } | |
532 | } | |
c5aa993b | 533 | |
1211c4e4 AC |
534 | fip->saved_regs[PC_REGNUM] = fip->frame + 4; |
535 | fip->saved_regs[FP_REGNUM] = fip->frame; | |
c906108c SS |
536 | } |
537 | ||
538 | /* return pc of first real instruction */ | |
539 | ||
540 | int | |
541 | i386_skip_prologue (pc) | |
542 | int pc; | |
543 | { | |
544 | unsigned char op; | |
545 | int i; | |
c5aa993b JM |
546 | static unsigned char pic_pat[6] = |
547 | {0xe8, 0, 0, 0, 0, /* call 0x0 */ | |
548 | 0x5b, /* popl %ebx */ | |
549 | }; | |
c906108c | 550 | CORE_ADDR pos; |
c5aa993b | 551 | |
c906108c SS |
552 | if (i386_get_frame_setup (pc) < 0) |
553 | return (pc); | |
c5aa993b | 554 | |
c906108c SS |
555 | /* found valid frame setup - codestream now points to |
556 | * start of push instructions for saving registers | |
557 | */ | |
c5aa993b | 558 | |
c906108c SS |
559 | /* skip over register saves */ |
560 | for (i = 0; i < 8; i++) | |
561 | { | |
562 | op = codestream_peek (); | |
563 | /* break if not pushl inst */ | |
c5aa993b | 564 | if (op < 0x50 || op > 0x57) |
c906108c SS |
565 | break; |
566 | codestream_get (); | |
567 | } | |
568 | ||
569 | /* The native cc on SVR4 in -K PIC mode inserts the following code to get | |
570 | the address of the global offset table (GOT) into register %ebx. | |
c5aa993b JM |
571 | call 0x0 |
572 | popl %ebx | |
573 | movl %ebx,x(%ebp) (optional) | |
574 | addl y,%ebx | |
c906108c SS |
575 | This code is with the rest of the prologue (at the end of the |
576 | function), so we have to skip it to get to the first real | |
577 | instruction at the start of the function. */ | |
c5aa993b | 578 | |
c906108c SS |
579 | pos = codestream_tell (); |
580 | for (i = 0; i < 6; i++) | |
581 | { | |
582 | op = codestream_get (); | |
c5aa993b | 583 | if (pic_pat[i] != op) |
c906108c SS |
584 | break; |
585 | } | |
586 | if (i == 6) | |
587 | { | |
588 | unsigned char buf[4]; | |
589 | long delta = 6; | |
590 | ||
591 | op = codestream_get (); | |
c5aa993b | 592 | if (op == 0x89) /* movl %ebx, x(%ebp) */ |
c906108c SS |
593 | { |
594 | op = codestream_get (); | |
c5aa993b | 595 | if (op == 0x5d) /* one byte offset from %ebp */ |
c906108c SS |
596 | { |
597 | delta += 3; | |
598 | codestream_read (buf, 1); | |
599 | } | |
c5aa993b | 600 | else if (op == 0x9d) /* four byte offset from %ebp */ |
c906108c SS |
601 | { |
602 | delta += 6; | |
603 | codestream_read (buf, 4); | |
604 | } | |
c5aa993b JM |
605 | else /* unexpected instruction */ |
606 | delta = -1; | |
607 | op = codestream_get (); | |
c906108c | 608 | } |
c5aa993b JM |
609 | /* addl y,%ebx */ |
610 | if (delta > 0 && op == 0x81 && codestream_get () == 0xc3) | |
c906108c | 611 | { |
c5aa993b | 612 | pos += delta + 6; |
c906108c SS |
613 | } |
614 | } | |
615 | codestream_seek (pos); | |
c5aa993b | 616 | |
c906108c | 617 | i386_follow_jump (); |
c5aa993b | 618 | |
c906108c SS |
619 | return (codestream_tell ()); |
620 | } | |
621 | ||
622 | void | |
623 | i386_push_dummy_frame () | |
624 | { | |
625 | CORE_ADDR sp = read_register (SP_REGNUM); | |
626 | int regnum; | |
627 | char regbuf[MAX_REGISTER_RAW_SIZE]; | |
c5aa993b | 628 | |
c906108c SS |
629 | sp = push_word (sp, read_register (PC_REGNUM)); |
630 | sp = push_word (sp, read_register (FP_REGNUM)); | |
631 | write_register (FP_REGNUM, sp); | |
632 | for (regnum = 0; regnum < NUM_REGS; regnum++) | |
633 | { | |
634 | read_register_gen (regnum, regbuf); | |
635 | sp = push_bytes (sp, regbuf, REGISTER_RAW_SIZE (regnum)); | |
636 | } | |
637 | write_register (SP_REGNUM, sp); | |
638 | } | |
639 | ||
640 | void | |
641 | i386_pop_frame () | |
642 | { | |
643 | struct frame_info *frame = get_current_frame (); | |
644 | CORE_ADDR fp; | |
645 | int regnum; | |
c906108c | 646 | char regbuf[MAX_REGISTER_RAW_SIZE]; |
c5aa993b | 647 | |
c906108c | 648 | fp = FRAME_FP (frame); |
1211c4e4 AC |
649 | i386_frame_init_saved_regs (frame); |
650 | ||
c5aa993b | 651 | for (regnum = 0; regnum < NUM_REGS; regnum++) |
c906108c SS |
652 | { |
653 | CORE_ADDR adr; | |
1211c4e4 | 654 | adr = frame->saved_regs[regnum]; |
c906108c SS |
655 | if (adr) |
656 | { | |
657 | read_memory (adr, regbuf, REGISTER_RAW_SIZE (regnum)); | |
658 | write_register_bytes (REGISTER_BYTE (regnum), regbuf, | |
659 | REGISTER_RAW_SIZE (regnum)); | |
660 | } | |
661 | } | |
662 | write_register (FP_REGNUM, read_memory_integer (fp, 4)); | |
663 | write_register (PC_REGNUM, read_memory_integer (fp + 4, 4)); | |
664 | write_register (SP_REGNUM, fp + 8); | |
665 | flush_cached_frames (); | |
666 | } | |
667 | ||
668 | #ifdef GET_LONGJMP_TARGET | |
669 | ||
670 | /* Figure out where the longjmp will land. Slurp the args out of the stack. | |
671 | We expect the first arg to be a pointer to the jmp_buf structure from which | |
672 | we extract the pc (JB_PC) that we will land at. The pc is copied into PC. | |
673 | This routine returns true on success. */ | |
674 | ||
675 | int | |
c5aa993b | 676 | get_longjmp_target (pc) |
c906108c SS |
677 | CORE_ADDR *pc; |
678 | { | |
679 | char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT]; | |
680 | CORE_ADDR sp, jb_addr; | |
681 | ||
682 | sp = read_register (SP_REGNUM); | |
683 | ||
c5aa993b | 684 | if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack */ |
c906108c SS |
685 | buf, |
686 | TARGET_PTR_BIT / TARGET_CHAR_BIT)) | |
687 | return 0; | |
688 | ||
689 | jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); | |
690 | ||
691 | if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf, | |
692 | TARGET_PTR_BIT / TARGET_CHAR_BIT)) | |
693 | return 0; | |
694 | ||
695 | *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); | |
696 | ||
697 | return 1; | |
698 | } | |
699 | ||
700 | #endif /* GET_LONGJMP_TARGET */ | |
701 | ||
1a309862 MK |
702 | /* These registers are used for returning integers (and on some |
703 | targets also for returning `struct' and `union' values when their | |
704 | size and alignment match an integer type. */ | |
705 | #define LOW_RETURN_REGNUM 0 /* %eax */ | |
706 | #define HIGH_RETURN_REGNUM 2 /* %edx */ | |
707 | ||
708 | /* Extract from an array REGBUF containing the (raw) register state, a | |
709 | function return value of TYPE, and copy that, in virtual format, | |
710 | into VALBUF. */ | |
711 | ||
c906108c | 712 | void |
1a309862 | 713 | i386_extract_return_value (struct type *type, char *regbuf, char *valbuf) |
c906108c | 714 | { |
1a309862 MK |
715 | int len = TYPE_LENGTH (type); |
716 | ||
c5aa993b | 717 | if (TYPE_CODE_FLT == TYPE_CODE (type)) |
c906108c | 718 | { |
1a309862 MK |
719 | if (NUM_FREGS == 0) |
720 | { | |
721 | warning ("Cannot find floating-point return value."); | |
722 | memset (valbuf, 0, len); | |
723 | } | |
724 | ||
725 | /* Floating-point return values can be found in %st(0). */ | |
726 | if (len == TARGET_LONG_DOUBLE_BIT / TARGET_CHAR_BIT | |
727 | && TARGET_LONG_DOUBLE_FORMAT == &floatformat_i387_ext) | |
728 | { | |
729 | /* Copy straight over, but take care of the padding. */ | |
730 | memcpy (valbuf, ®buf[REGISTER_BYTE (FP0_REGNUM)], | |
731 | FPU_REG_RAW_SIZE); | |
732 | memset (valbuf + FPU_REG_RAW_SIZE, 0, len - FPU_REG_RAW_SIZE); | |
733 | } | |
734 | else | |
735 | { | |
736 | /* Convert the extended floating-point number found in | |
737 | %st(0) to the desired type. This is probably not exactly | |
738 | how it would happen on the target itself, but it is the | |
739 | best we can do. */ | |
740 | DOUBLEST val; | |
741 | floatformat_to_doublest (&floatformat_i387_ext, | |
742 | ®buf[REGISTER_BYTE (FP0_REGNUM)], &val); | |
743 | store_floating (valbuf, TYPE_LENGTH (type), val); | |
744 | } | |
c906108c SS |
745 | } |
746 | else | |
c5aa993b | 747 | { |
d4f3574e SS |
748 | int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM); |
749 | int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM); | |
750 | ||
751 | if (len <= low_size) | |
1a309862 | 752 | memcpy (valbuf, ®buf[REGISTER_BYTE (LOW_RETURN_REGNUM)], len); |
d4f3574e SS |
753 | else if (len <= (low_size + high_size)) |
754 | { | |
755 | memcpy (valbuf, | |
1a309862 | 756 | ®buf[REGISTER_BYTE (LOW_RETURN_REGNUM)], low_size); |
d4f3574e | 757 | memcpy (valbuf + low_size, |
1a309862 | 758 | ®buf[REGISTER_BYTE (HIGH_RETURN_REGNUM)], len - low_size); |
d4f3574e SS |
759 | } |
760 | else | |
1a309862 | 761 | internal_error ("Cannot extract return value of %d bytes long.", len); |
c906108c SS |
762 | } |
763 | } | |
764 | ||
ac27f131 MK |
765 | /* Convert data from raw format for register REGNUM in buffer FROM to |
766 | virtual format with type TYPE in buffer TO. In principle both | |
767 | formats are identical except that the virtual format has two extra | |
768 | bytes appended that aren't used. We set these to zero. */ | |
769 | ||
770 | void | |
771 | i386_register_convert_to_virtual (int regnum, struct type *type, | |
772 | char *from, char *to) | |
773 | { | |
774 | /* Copy straight over, but take care of the padding. */ | |
775 | memcpy (to, from, FPU_REG_RAW_SIZE); | |
776 | memset (to + FPU_REG_RAW_SIZE, 0, TYPE_LENGTH (type) - FPU_REG_RAW_SIZE); | |
777 | } | |
778 | ||
779 | /* Convert data from virtual format with type TYPE in buffer FROM to | |
780 | raw format for register REGNUM in buffer TO. Simply omit the two | |
781 | unused bytes. */ | |
782 | ||
783 | void | |
784 | i386_register_convert_to_raw (struct type *type, int regnum, | |
785 | char *from, char *to) | |
786 | { | |
787 | memcpy (to, from, FPU_REG_RAW_SIZE); | |
788 | } | |
789 | ||
790 | \f | |
c906108c SS |
791 | #ifdef I386V4_SIGTRAMP_SAVED_PC |
792 | /* Get saved user PC for sigtramp from the pushed ucontext on the stack | |
793 | for all three variants of SVR4 sigtramps. */ | |
794 | ||
795 | CORE_ADDR | |
796 | i386v4_sigtramp_saved_pc (frame) | |
797 | struct frame_info *frame; | |
798 | { | |
799 | CORE_ADDR saved_pc_offset = 4; | |
800 | char *name = NULL; | |
801 | ||
802 | find_pc_partial_function (frame->pc, &name, NULL, NULL); | |
803 | if (name) | |
804 | { | |
805 | if (STREQ (name, "_sigreturn")) | |
806 | saved_pc_offset = 132 + 14 * 4; | |
807 | else if (STREQ (name, "_sigacthandler")) | |
808 | saved_pc_offset = 80 + 14 * 4; | |
809 | else if (STREQ (name, "sigvechandler")) | |
810 | saved_pc_offset = 120 + 14 * 4; | |
811 | } | |
812 | ||
813 | if (frame->next) | |
814 | return read_memory_integer (frame->next->frame + saved_pc_offset, 4); | |
815 | return read_memory_integer (read_register (SP_REGNUM) + saved_pc_offset, 4); | |
816 | } | |
817 | #endif /* I386V4_SIGTRAMP_SAVED_PC */ | |
818 | ||
a0b3c4fd | 819 | |
c906108c SS |
820 | #ifdef STATIC_TRANSFORM_NAME |
821 | /* SunPRO encodes the static variables. This is not related to C++ mangling, | |
822 | it is done for C too. */ | |
823 | ||
824 | char * | |
825 | sunpro_static_transform_name (name) | |
826 | char *name; | |
827 | { | |
828 | char *p; | |
829 | if (IS_STATIC_TRANSFORM_NAME (name)) | |
830 | { | |
831 | /* For file-local statics there will be a period, a bunch | |
c5aa993b JM |
832 | of junk (the contents of which match a string given in the |
833 | N_OPT), a period and the name. For function-local statics | |
834 | there will be a bunch of junk (which seems to change the | |
835 | second character from 'A' to 'B'), a period, the name of the | |
836 | function, and the name. So just skip everything before the | |
837 | last period. */ | |
c906108c SS |
838 | p = strrchr (name, '.'); |
839 | if (p != NULL) | |
840 | name = p + 1; | |
841 | } | |
842 | return name; | |
843 | } | |
844 | #endif /* STATIC_TRANSFORM_NAME */ | |
845 | ||
846 | ||
847 | ||
848 | /* Stuff for WIN32 PE style DLL's but is pretty generic really. */ | |
849 | ||
850 | CORE_ADDR | |
851 | skip_trampoline_code (pc, name) | |
852 | CORE_ADDR pc; | |
853 | char *name; | |
854 | { | |
c5aa993b | 855 | if (pc && read_memory_unsigned_integer (pc, 2) == 0x25ff) /* jmp *(dest) */ |
c906108c | 856 | { |
c5aa993b | 857 | unsigned long indirect = read_memory_unsigned_integer (pc + 2, 4); |
c906108c | 858 | struct minimal_symbol *indsym = |
c5aa993b JM |
859 | indirect ? lookup_minimal_symbol_by_pc (indirect) : 0; |
860 | char *symname = indsym ? SYMBOL_NAME (indsym) : 0; | |
c906108c | 861 | |
c5aa993b | 862 | if (symname) |
c906108c | 863 | { |
c5aa993b JM |
864 | if (strncmp (symname, "__imp_", 6) == 0 |
865 | || strncmp (symname, "_imp_", 5) == 0) | |
c906108c SS |
866 | return name ? 1 : read_memory_unsigned_integer (indirect, 4); |
867 | } | |
868 | } | |
869 | return 0; /* not a trampoline */ | |
870 | } | |
871 | ||
872 | static int | |
873 | gdb_print_insn_i386 (memaddr, info) | |
874 | bfd_vma memaddr; | |
c5aa993b | 875 | disassemble_info *info; |
c906108c SS |
876 | { |
877 | if (disassembly_flavor == att_flavor) | |
878 | return print_insn_i386_att (memaddr, info); | |
879 | else if (disassembly_flavor == intel_flavor) | |
880 | return print_insn_i386_intel (memaddr, info); | |
7a292a7a SS |
881 | /* Never reached - disassembly_flavour is always either att_flavor |
882 | or intel_flavor */ | |
883 | abort (); | |
884 | } | |
885 | ||
886 | /* If the disassembly mode is intel, we have to also switch the | |
887 | bfd mach_type. This function is run in the set disassembly_flavor | |
888 | command, and does that. */ | |
889 | ||
890 | static void | |
891 | set_disassembly_flavor_sfunc (args, from_tty, c) | |
892 | char *args; | |
893 | int from_tty; | |
894 | struct cmd_list_element *c; | |
895 | { | |
896 | set_disassembly_flavor (); | |
7a292a7a SS |
897 | } |
898 | ||
899 | static void | |
900 | set_disassembly_flavor () | |
901 | { | |
902 | if (disassembly_flavor == att_flavor) | |
903 | set_architecture_from_arch_mach (bfd_arch_i386, bfd_mach_i386_i386); | |
904 | else if (disassembly_flavor == intel_flavor) | |
905 | set_architecture_from_arch_mach (bfd_arch_i386, bfd_mach_i386_i386_intel_syntax); | |
c906108c SS |
906 | } |
907 | ||
2acceee2 | 908 | |
c906108c SS |
909 | void |
910 | _initialize_i386_tdep () | |
911 | { | |
917317f4 JM |
912 | /* Initialize the table saying where each register starts in the |
913 | register file. */ | |
914 | { | |
915 | int i, offset; | |
916 | ||
917 | offset = 0; | |
918 | for (i = 0; i < MAX_NUM_REGS; i++) | |
919 | { | |
920 | i386_register_byte[i] = offset; | |
921 | offset += i386_register_raw_size[i]; | |
922 | } | |
923 | } | |
924 | ||
925 | /* Initialize the table of virtual register sizes. */ | |
926 | { | |
927 | int i; | |
928 | ||
929 | for (i = 0; i < MAX_NUM_REGS; i++) | |
930 | i386_register_virtual_size[i] = TYPE_LENGTH (REGISTER_VIRTUAL_TYPE (i)); | |
931 | } | |
c5aa993b | 932 | |
c906108c SS |
933 | tm_print_insn = gdb_print_insn_i386; |
934 | tm_print_insn_info.mach = bfd_lookup_arch (bfd_arch_i386, 0)->mach; | |
935 | ||
936 | /* Add the variable that controls the disassembly flavor */ | |
917317f4 JM |
937 | { |
938 | struct cmd_list_element *new_cmd; | |
7a292a7a | 939 | |
917317f4 JM |
940 | new_cmd = add_set_enum_cmd ("disassembly-flavor", no_class, |
941 | valid_flavors, | |
1ed2a135 | 942 | &disassembly_flavor, |
917317f4 | 943 | "Set the disassembly flavor, the valid values are \"att\" and \"intel\", \ |
c906108c | 944 | and the default value is \"att\".", |
917317f4 JM |
945 | &setlist); |
946 | new_cmd->function.sfunc = set_disassembly_flavor_sfunc; | |
947 | add_show_from_set (new_cmd, &showlist); | |
948 | } | |
c5aa993b | 949 | |
7a292a7a SS |
950 | /* Finally, initialize the disassembly flavor to the default given |
951 | in the disassembly_flavor variable */ | |
c906108c | 952 | |
7a292a7a | 953 | set_disassembly_flavor (); |
c906108c | 954 | } |