]>
Commit | Line | Data |
---|---|---|
c906108c | 1 | /* Intel 386 target-dependent stuff. |
8e65ff28 | 2 | Copyright (C) 1988, 1989, 1991, 1994, 1995, 1996, 1998, 2001 |
c906108c SS |
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" | |
b4a20239 | 32 | #include "arch-utils.h" |
4e052eda | 33 | #include "regcache.h" |
c906108c | 34 | |
a14ed312 | 35 | static long i386_get_frame_setup (CORE_ADDR); |
c906108c | 36 | |
a14ed312 | 37 | static void i386_follow_jump (void); |
c906108c | 38 | |
a14ed312 | 39 | static void codestream_read (unsigned char *, int); |
c906108c | 40 | |
a14ed312 | 41 | static void codestream_seek (CORE_ADDR); |
c906108c | 42 | |
a14ed312 | 43 | static unsigned char codestream_fill (int); |
c906108c | 44 | |
a14ed312 | 45 | CORE_ADDR skip_trampoline_code (CORE_ADDR, char *); |
c906108c SS |
46 | |
47 | static int gdb_print_insn_i386 (bfd_vma, disassemble_info *); | |
48 | ||
a14ed312 | 49 | void _initialize_i386_tdep (void); |
c906108c | 50 | |
917317f4 JM |
51 | /* i386_register_byte[i] is the offset into the register file of the |
52 | start of register number i. We initialize this from | |
53 | i386_register_raw_size. */ | |
54 | int i386_register_byte[MAX_NUM_REGS]; | |
55 | ||
ceb4951f JB |
56 | /* i386_register_raw_size[i] is the number of bytes of storage in |
57 | GDB's register array occupied by register i. */ | |
917317f4 JM |
58 | int i386_register_raw_size[MAX_NUM_REGS] = { |
59 | 4, 4, 4, 4, | |
60 | 4, 4, 4, 4, | |
61 | 4, 4, 4, 4, | |
62 | 4, 4, 4, 4, | |
63 | 10, 10, 10, 10, | |
64 | 10, 10, 10, 10, | |
65 | 4, 4, 4, 4, | |
66 | 4, 4, 4, 4, | |
67 | 16, 16, 16, 16, | |
68 | 16, 16, 16, 16, | |
69 | 4 | |
70 | }; | |
71 | ||
72 | /* i386_register_virtual_size[i] is the size in bytes of the virtual | |
73 | type of register i. */ | |
74 | int i386_register_virtual_size[MAX_NUM_REGS]; | |
75 | ||
76 | ||
c906108c | 77 | /* This is the variable the is set with "set disassembly-flavor", |
c5aa993b | 78 | and its legitimate values. */ |
53904c9e AC |
79 | static const char att_flavor[] = "att"; |
80 | static const char intel_flavor[] = "intel"; | |
81 | static const char *valid_flavors[] = | |
c5aa993b | 82 | { |
c906108c SS |
83 | att_flavor, |
84 | intel_flavor, | |
85 | NULL | |
86 | }; | |
53904c9e | 87 | static const char *disassembly_flavor = att_flavor; |
c906108c | 88 | |
a14ed312 | 89 | static void i386_print_register (char *, int, int); |
d4f3574e | 90 | |
7a292a7a | 91 | /* This is used to keep the bfd arch_info in sync with the disassembly flavor. */ |
a14ed312 KB |
92 | static void set_disassembly_flavor_sfunc (char *, int, |
93 | struct cmd_list_element *); | |
94 | static void set_disassembly_flavor (void); | |
7a292a7a | 95 | |
c906108c SS |
96 | /* Stdio style buffering was used to minimize calls to ptrace, but this |
97 | buffering did not take into account that the code section being accessed | |
98 | may not be an even number of buffers long (even if the buffer is only | |
99 | sizeof(int) long). In cases where the code section size happened to | |
100 | be a non-integral number of buffers long, attempting to read the last | |
101 | buffer would fail. Simply using target_read_memory and ignoring errors, | |
102 | rather than read_memory, is not the correct solution, since legitimate | |
103 | access errors would then be totally ignored. To properly handle this | |
104 | situation and continue to use buffering would require that this code | |
105 | be able to determine the minimum code section size granularity (not the | |
106 | alignment of the section itself, since the actual failing case that | |
107 | pointed out this problem had a section alignment of 4 but was not a | |
108 | multiple of 4 bytes long), on a target by target basis, and then | |
109 | adjust it's buffer size accordingly. This is messy, but potentially | |
110 | feasible. It probably needs the bfd library's help and support. For | |
111 | now, the buffer size is set to 1. (FIXME -fnf) */ | |
112 | ||
113 | #define CODESTREAM_BUFSIZ 1 /* Was sizeof(int), see note above. */ | |
114 | static CORE_ADDR codestream_next_addr; | |
115 | static CORE_ADDR codestream_addr; | |
116 | static unsigned char codestream_buf[CODESTREAM_BUFSIZ]; | |
117 | static int codestream_off; | |
118 | static int codestream_cnt; | |
119 | ||
120 | #define codestream_tell() (codestream_addr + codestream_off) | |
121 | #define codestream_peek() (codestream_cnt == 0 ? \ | |
122 | codestream_fill(1): codestream_buf[codestream_off]) | |
123 | #define codestream_get() (codestream_cnt-- == 0 ? \ | |
124 | codestream_fill(0) : codestream_buf[codestream_off++]) | |
125 | ||
c5aa993b | 126 | static unsigned char |
fba45db2 | 127 | codestream_fill (int peek_flag) |
c906108c SS |
128 | { |
129 | codestream_addr = codestream_next_addr; | |
130 | codestream_next_addr += CODESTREAM_BUFSIZ; | |
131 | codestream_off = 0; | |
132 | codestream_cnt = CODESTREAM_BUFSIZ; | |
133 | read_memory (codestream_addr, (char *) codestream_buf, CODESTREAM_BUFSIZ); | |
c5aa993b | 134 | |
c906108c | 135 | if (peek_flag) |
c5aa993b | 136 | return (codestream_peek ()); |
c906108c | 137 | else |
c5aa993b | 138 | return (codestream_get ()); |
c906108c SS |
139 | } |
140 | ||
141 | static void | |
fba45db2 | 142 | codestream_seek (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 | |
fba45db2 | 153 | codestream_read (unsigned char *buf, int count) |
c906108c SS |
154 | { |
155 | unsigned char *p; | |
156 | int i; | |
157 | p = buf; | |
158 | for (i = 0; i < count; i++) | |
159 | *p++ = codestream_get (); | |
160 | } | |
161 | ||
162 | /* next instruction is a jump, move to target */ | |
163 | ||
164 | static void | |
fba45db2 | 165 | i386_follow_jump (void) |
c906108c SS |
166 | { |
167 | unsigned char buf[4]; | |
168 | long delta; | |
169 | ||
170 | int data16; | |
171 | CORE_ADDR pos; | |
172 | ||
173 | pos = codestream_tell (); | |
174 | ||
175 | data16 = 0; | |
176 | if (codestream_peek () == 0x66) | |
177 | { | |
178 | codestream_get (); | |
179 | data16 = 1; | |
180 | } | |
181 | ||
182 | switch (codestream_get ()) | |
183 | { | |
184 | case 0xe9: | |
185 | /* relative jump: if data16 == 0, disp32, else disp16 */ | |
186 | if (data16) | |
187 | { | |
188 | codestream_read (buf, 2); | |
189 | delta = extract_signed_integer (buf, 2); | |
190 | ||
191 | /* include size of jmp inst (including the 0x66 prefix). */ | |
c5aa993b | 192 | pos += delta + 4; |
c906108c SS |
193 | } |
194 | else | |
195 | { | |
196 | codestream_read (buf, 4); | |
197 | delta = extract_signed_integer (buf, 4); | |
198 | ||
199 | pos += delta + 5; | |
200 | } | |
201 | break; | |
202 | case 0xeb: | |
203 | /* relative jump, disp8 (ignore data16) */ | |
204 | codestream_read (buf, 1); | |
205 | /* Sign-extend it. */ | |
206 | delta = extract_signed_integer (buf, 1); | |
207 | ||
208 | pos += delta + 2; | |
209 | break; | |
210 | } | |
211 | codestream_seek (pos); | |
212 | } | |
213 | ||
214 | /* | |
215 | * find & return amound a local space allocated, and advance codestream to | |
216 | * first register push (if any) | |
217 | * | |
218 | * if entry sequence doesn't make sense, return -1, and leave | |
219 | * codestream pointer random | |
220 | */ | |
221 | ||
222 | static long | |
fba45db2 | 223 | i386_get_frame_setup (CORE_ADDR pc) |
c906108c SS |
224 | { |
225 | unsigned char op; | |
226 | ||
227 | codestream_seek (pc); | |
228 | ||
229 | i386_follow_jump (); | |
230 | ||
231 | op = codestream_get (); | |
232 | ||
233 | if (op == 0x58) /* popl %eax */ | |
234 | { | |
235 | /* | |
236 | * this function must start with | |
237 | * | |
c5aa993b | 238 | * popl %eax 0x58 |
c906108c SS |
239 | * xchgl %eax, (%esp) 0x87 0x04 0x24 |
240 | * or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00 | |
241 | * | |
242 | * (the system 5 compiler puts out the second xchg | |
243 | * inst, and the assembler doesn't try to optimize it, | |
244 | * so the 'sib' form gets generated) | |
245 | * | |
246 | * this sequence is used to get the address of the return | |
247 | * buffer for a function that returns a structure | |
248 | */ | |
249 | int pos; | |
250 | unsigned char buf[4]; | |
c5aa993b JM |
251 | static unsigned char proto1[3] = |
252 | {0x87, 0x04, 0x24}; | |
253 | static unsigned char proto2[4] = | |
254 | {0x87, 0x44, 0x24, 0x00}; | |
c906108c SS |
255 | pos = codestream_tell (); |
256 | codestream_read (buf, 4); | |
257 | if (memcmp (buf, proto1, 3) == 0) | |
258 | pos += 3; | |
259 | else if (memcmp (buf, proto2, 4) == 0) | |
260 | pos += 4; | |
261 | ||
262 | codestream_seek (pos); | |
c5aa993b | 263 | op = codestream_get (); /* update next opcode */ |
c906108c SS |
264 | } |
265 | ||
266 | if (op == 0x68 || op == 0x6a) | |
267 | { | |
268 | /* | |
269 | * this function may start with | |
270 | * | |
271 | * pushl constant | |
272 | * call _probe | |
273 | * addl $4, %esp | |
274 | * followed by | |
275 | * pushl %ebp | |
276 | * etc. | |
277 | */ | |
278 | int pos; | |
279 | unsigned char buf[8]; | |
280 | ||
281 | /* Skip past the pushl instruction; it has either a one-byte | |
282 | or a four-byte operand, depending on the opcode. */ | |
283 | pos = codestream_tell (); | |
284 | if (op == 0x68) | |
285 | pos += 4; | |
286 | else | |
287 | pos += 1; | |
288 | codestream_seek (pos); | |
289 | ||
290 | /* Read the following 8 bytes, which should be "call _probe" (6 bytes) | |
291 | followed by "addl $4,%esp" (2 bytes). */ | |
292 | codestream_read (buf, sizeof (buf)); | |
293 | if (buf[0] == 0xe8 && buf[6] == 0xc4 && buf[7] == 0x4) | |
294 | pos += sizeof (buf); | |
295 | codestream_seek (pos); | |
c5aa993b | 296 | op = codestream_get (); /* update next opcode */ |
c906108c SS |
297 | } |
298 | ||
299 | if (op == 0x55) /* pushl %ebp */ | |
c5aa993b | 300 | { |
c906108c SS |
301 | /* check for movl %esp, %ebp - can be written two ways */ |
302 | switch (codestream_get ()) | |
303 | { | |
304 | case 0x8b: | |
305 | if (codestream_get () != 0xec) | |
306 | return (-1); | |
307 | break; | |
308 | case 0x89: | |
309 | if (codestream_get () != 0xe5) | |
310 | return (-1); | |
311 | break; | |
312 | default: | |
313 | return (-1); | |
314 | } | |
315 | /* check for stack adjustment | |
c5aa993b | 316 | |
c906108c SS |
317 | * subl $XXX, %esp |
318 | * | |
319 | * note: you can't subtract a 16 bit immediate | |
320 | * from a 32 bit reg, so we don't have to worry | |
321 | * about a data16 prefix | |
322 | */ | |
323 | op = codestream_peek (); | |
324 | if (op == 0x83) | |
325 | { | |
326 | /* subl with 8 bit immed */ | |
327 | codestream_get (); | |
328 | if (codestream_get () != 0xec) | |
329 | /* Some instruction starting with 0x83 other than subl. */ | |
330 | { | |
331 | codestream_seek (codestream_tell () - 2); | |
332 | return 0; | |
333 | } | |
334 | /* subl with signed byte immediate | |
335 | * (though it wouldn't make sense to be negative) | |
336 | */ | |
c5aa993b | 337 | return (codestream_get ()); |
c906108c SS |
338 | } |
339 | else if (op == 0x81) | |
340 | { | |
341 | char buf[4]; | |
342 | /* Maybe it is subl with 32 bit immedediate. */ | |
c5aa993b | 343 | codestream_get (); |
c906108c SS |
344 | if (codestream_get () != 0xec) |
345 | /* Some instruction starting with 0x81 other than subl. */ | |
346 | { | |
347 | codestream_seek (codestream_tell () - 2); | |
348 | return 0; | |
349 | } | |
350 | /* It is subl with 32 bit immediate. */ | |
c5aa993b | 351 | codestream_read ((unsigned char *) buf, 4); |
c906108c SS |
352 | return extract_signed_integer (buf, 4); |
353 | } | |
354 | else | |
355 | { | |
356 | return (0); | |
357 | } | |
358 | } | |
359 | else if (op == 0xc8) | |
360 | { | |
361 | char buf[2]; | |
362 | /* enter instruction: arg is 16 bit unsigned immed */ | |
c5aa993b JM |
363 | codestream_read ((unsigned char *) buf, 2); |
364 | codestream_get (); /* flush final byte of enter instruction */ | |
c906108c SS |
365 | return extract_unsigned_integer (buf, 2); |
366 | } | |
367 | return (-1); | |
368 | } | |
369 | ||
370 | /* Return number of args passed to a frame. | |
371 | Can return -1, meaning no way to tell. */ | |
372 | ||
373 | int | |
fba45db2 | 374 | i386_frame_num_args (struct frame_info *fi) |
c906108c SS |
375 | { |
376 | #if 1 | |
377 | return -1; | |
378 | #else | |
379 | /* This loses because not only might the compiler not be popping the | |
380 | args right after the function call, it might be popping args from both | |
381 | this call and a previous one, and we would say there are more args | |
382 | than there really are. */ | |
383 | ||
c5aa993b JM |
384 | int retpc; |
385 | unsigned char op; | |
c906108c SS |
386 | struct frame_info *pfi; |
387 | ||
388 | /* on the 386, the instruction following the call could be: | |
389 | popl %ecx - one arg | |
390 | addl $imm, %esp - imm/4 args; imm may be 8 or 32 bits | |
391 | anything else - zero args */ | |
392 | ||
393 | int frameless; | |
394 | ||
392a587b | 395 | frameless = FRAMELESS_FUNCTION_INVOCATION (fi); |
c906108c SS |
396 | if (frameless) |
397 | /* In the absence of a frame pointer, GDB doesn't get correct values | |
398 | for nameless arguments. Return -1, so it doesn't print any | |
399 | nameless arguments. */ | |
400 | return -1; | |
401 | ||
c5aa993b | 402 | pfi = get_prev_frame (fi); |
c906108c SS |
403 | if (pfi == 0) |
404 | { | |
405 | /* Note: this can happen if we are looking at the frame for | |
c5aa993b JM |
406 | main, because FRAME_CHAIN_VALID won't let us go into |
407 | start. If we have debugging symbols, that's not really | |
408 | a big deal; it just means it will only show as many arguments | |
409 | to main as are declared. */ | |
c906108c SS |
410 | return -1; |
411 | } | |
412 | else | |
413 | { | |
c5aa993b JM |
414 | retpc = pfi->pc; |
415 | op = read_memory_integer (retpc, 1); | |
416 | if (op == 0x59) | |
417 | /* pop %ecx */ | |
418 | return 1; | |
c906108c SS |
419 | else if (op == 0x83) |
420 | { | |
c5aa993b JM |
421 | op = read_memory_integer (retpc + 1, 1); |
422 | if (op == 0xc4) | |
423 | /* addl $<signed imm 8 bits>, %esp */ | |
424 | return (read_memory_integer (retpc + 2, 1) & 0xff) / 4; | |
c906108c SS |
425 | else |
426 | return 0; | |
427 | } | |
428 | else if (op == 0x81) | |
c5aa993b JM |
429 | { /* add with 32 bit immediate */ |
430 | op = read_memory_integer (retpc + 1, 1); | |
431 | if (op == 0xc4) | |
432 | /* addl $<imm 32>, %esp */ | |
433 | return read_memory_integer (retpc + 2, 4) / 4; | |
c906108c SS |
434 | else |
435 | return 0; | |
436 | } | |
437 | else | |
438 | { | |
439 | return 0; | |
440 | } | |
441 | } | |
442 | #endif | |
443 | } | |
444 | ||
445 | /* | |
446 | * parse the first few instructions of the function to see | |
447 | * what registers were stored. | |
448 | * | |
449 | * We handle these cases: | |
450 | * | |
451 | * The startup sequence can be at the start of the function, | |
452 | * or the function can start with a branch to startup code at the end. | |
453 | * | |
454 | * %ebp can be set up with either the 'enter' instruction, or | |
455 | * 'pushl %ebp, movl %esp, %ebp' (enter is too slow to be useful, | |
456 | * but was once used in the sys5 compiler) | |
457 | * | |
458 | * Local space is allocated just below the saved %ebp by either the | |
459 | * 'enter' instruction, or by 'subl $<size>, %esp'. 'enter' has | |
460 | * a 16 bit unsigned argument for space to allocate, and the | |
461 | * 'addl' instruction could have either a signed byte, or | |
462 | * 32 bit immediate. | |
463 | * | |
464 | * Next, the registers used by this function are pushed. In | |
465 | * the sys5 compiler they will always be in the order: %edi, %esi, %ebx | |
466 | * (and sometimes a harmless bug causes it to also save but not restore %eax); | |
467 | * however, the code below is willing to see the pushes in any order, | |
468 | * and will handle up to 8 of them. | |
469 | * | |
470 | * If the setup sequence is at the end of the function, then the | |
471 | * next instruction will be a branch back to the start. | |
472 | */ | |
473 | ||
474 | void | |
fba45db2 | 475 | i386_frame_init_saved_regs (struct frame_info *fip) |
c906108c SS |
476 | { |
477 | long locals = -1; | |
478 | unsigned char op; | |
479 | CORE_ADDR dummy_bottom; | |
480 | CORE_ADDR adr; | |
481 | CORE_ADDR pc; | |
482 | int i; | |
c5aa993b | 483 | |
1211c4e4 AC |
484 | if (fip->saved_regs) |
485 | return; | |
486 | ||
487 | frame_saved_regs_zalloc (fip); | |
c5aa993b | 488 | |
c906108c SS |
489 | /* if frame is the end of a dummy, compute where the |
490 | * beginning would be | |
491 | */ | |
492 | dummy_bottom = fip->frame - 4 - REGISTER_BYTES - CALL_DUMMY_LENGTH; | |
c5aa993b | 493 | |
c906108c | 494 | /* check if the PC is in the stack, in a dummy frame */ |
c5aa993b | 495 | if (dummy_bottom <= fip->pc && fip->pc <= fip->frame) |
c906108c SS |
496 | { |
497 | /* all regs were saved by push_call_dummy () */ | |
498 | adr = fip->frame; | |
c5aa993b | 499 | for (i = 0; i < NUM_REGS; i++) |
c906108c SS |
500 | { |
501 | adr -= REGISTER_RAW_SIZE (i); | |
1211c4e4 | 502 | fip->saved_regs[i] = adr; |
c906108c SS |
503 | } |
504 | return; | |
505 | } | |
c5aa993b | 506 | |
c906108c SS |
507 | pc = get_pc_function_start (fip->pc); |
508 | if (pc != 0) | |
509 | locals = i386_get_frame_setup (pc); | |
c5aa993b JM |
510 | |
511 | if (locals >= 0) | |
c906108c SS |
512 | { |
513 | adr = fip->frame - 4 - locals; | |
c5aa993b | 514 | for (i = 0; i < 8; i++) |
c906108c SS |
515 | { |
516 | op = codestream_get (); | |
517 | if (op < 0x50 || op > 0x57) | |
518 | break; | |
519 | #ifdef I386_REGNO_TO_SYMMETRY | |
520 | /* Dynix uses different internal numbering. Ick. */ | |
1211c4e4 | 521 | fip->saved_regs[I386_REGNO_TO_SYMMETRY (op - 0x50)] = adr; |
c906108c | 522 | #else |
1211c4e4 | 523 | fip->saved_regs[op - 0x50] = adr; |
c906108c SS |
524 | #endif |
525 | adr -= 4; | |
526 | } | |
527 | } | |
c5aa993b | 528 | |
1211c4e4 AC |
529 | fip->saved_regs[PC_REGNUM] = fip->frame + 4; |
530 | fip->saved_regs[FP_REGNUM] = fip->frame; | |
c906108c SS |
531 | } |
532 | ||
533 | /* return pc of first real instruction */ | |
534 | ||
535 | int | |
fba45db2 | 536 | i386_skip_prologue (int pc) |
c906108c SS |
537 | { |
538 | unsigned char op; | |
539 | int i; | |
c5aa993b JM |
540 | static unsigned char pic_pat[6] = |
541 | {0xe8, 0, 0, 0, 0, /* call 0x0 */ | |
542 | 0x5b, /* popl %ebx */ | |
543 | }; | |
c906108c | 544 | CORE_ADDR pos; |
c5aa993b | 545 | |
c906108c SS |
546 | if (i386_get_frame_setup (pc) < 0) |
547 | return (pc); | |
c5aa993b | 548 | |
c906108c SS |
549 | /* found valid frame setup - codestream now points to |
550 | * start of push instructions for saving registers | |
551 | */ | |
c5aa993b | 552 | |
c906108c SS |
553 | /* skip over register saves */ |
554 | for (i = 0; i < 8; i++) | |
555 | { | |
556 | op = codestream_peek (); | |
557 | /* break if not pushl inst */ | |
c5aa993b | 558 | if (op < 0x50 || op > 0x57) |
c906108c SS |
559 | break; |
560 | codestream_get (); | |
561 | } | |
562 | ||
563 | /* The native cc on SVR4 in -K PIC mode inserts the following code to get | |
564 | the address of the global offset table (GOT) into register %ebx. | |
c5aa993b JM |
565 | call 0x0 |
566 | popl %ebx | |
567 | movl %ebx,x(%ebp) (optional) | |
568 | addl y,%ebx | |
c906108c SS |
569 | This code is with the rest of the prologue (at the end of the |
570 | function), so we have to skip it to get to the first real | |
571 | instruction at the start of the function. */ | |
c5aa993b | 572 | |
c906108c SS |
573 | pos = codestream_tell (); |
574 | for (i = 0; i < 6; i++) | |
575 | { | |
576 | op = codestream_get (); | |
c5aa993b | 577 | if (pic_pat[i] != op) |
c906108c SS |
578 | break; |
579 | } | |
580 | if (i == 6) | |
581 | { | |
582 | unsigned char buf[4]; | |
583 | long delta = 6; | |
584 | ||
585 | op = codestream_get (); | |
c5aa993b | 586 | if (op == 0x89) /* movl %ebx, x(%ebp) */ |
c906108c SS |
587 | { |
588 | op = codestream_get (); | |
c5aa993b | 589 | if (op == 0x5d) /* one byte offset from %ebp */ |
c906108c SS |
590 | { |
591 | delta += 3; | |
592 | codestream_read (buf, 1); | |
593 | } | |
c5aa993b | 594 | else if (op == 0x9d) /* four byte offset from %ebp */ |
c906108c SS |
595 | { |
596 | delta += 6; | |
597 | codestream_read (buf, 4); | |
598 | } | |
c5aa993b JM |
599 | else /* unexpected instruction */ |
600 | delta = -1; | |
601 | op = codestream_get (); | |
c906108c | 602 | } |
c5aa993b JM |
603 | /* addl y,%ebx */ |
604 | if (delta > 0 && op == 0x81 && codestream_get () == 0xc3) | |
c906108c | 605 | { |
c5aa993b | 606 | pos += delta + 6; |
c906108c SS |
607 | } |
608 | } | |
609 | codestream_seek (pos); | |
c5aa993b | 610 | |
c906108c | 611 | i386_follow_jump (); |
c5aa993b | 612 | |
c906108c SS |
613 | return (codestream_tell ()); |
614 | } | |
615 | ||
616 | void | |
fba45db2 | 617 | i386_push_dummy_frame (void) |
c906108c SS |
618 | { |
619 | CORE_ADDR sp = read_register (SP_REGNUM); | |
620 | int regnum; | |
621 | char regbuf[MAX_REGISTER_RAW_SIZE]; | |
c5aa993b | 622 | |
c906108c SS |
623 | sp = push_word (sp, read_register (PC_REGNUM)); |
624 | sp = push_word (sp, read_register (FP_REGNUM)); | |
625 | write_register (FP_REGNUM, sp); | |
626 | for (regnum = 0; regnum < NUM_REGS; regnum++) | |
627 | { | |
628 | read_register_gen (regnum, regbuf); | |
629 | sp = push_bytes (sp, regbuf, REGISTER_RAW_SIZE (regnum)); | |
630 | } | |
631 | write_register (SP_REGNUM, sp); | |
632 | } | |
633 | ||
a7769679 MK |
634 | /* Insert the (relative) function address into the call sequence |
635 | stored at DYMMY. */ | |
636 | ||
637 | void | |
638 | i386_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs, | |
639 | value_ptr *args, struct type *type, int gcc_p) | |
640 | { | |
641 | int from, to, delta, loc; | |
642 | ||
643 | loc = (int)(read_register (SP_REGNUM) - CALL_DUMMY_LENGTH); | |
644 | from = loc + 5; | |
645 | to = (int)(fun); | |
646 | delta = to - from; | |
647 | ||
648 | *((char *)(dummy) + 1) = (delta & 0xff); | |
649 | *((char *)(dummy) + 2) = ((delta >> 8) & 0xff); | |
650 | *((char *)(dummy) + 3) = ((delta >> 16) & 0xff); | |
651 | *((char *)(dummy) + 4) = ((delta >> 24) & 0xff); | |
652 | } | |
653 | ||
c906108c | 654 | void |
fba45db2 | 655 | i386_pop_frame (void) |
c906108c SS |
656 | { |
657 | struct frame_info *frame = get_current_frame (); | |
658 | CORE_ADDR fp; | |
659 | int regnum; | |
c906108c | 660 | char regbuf[MAX_REGISTER_RAW_SIZE]; |
c5aa993b | 661 | |
c906108c | 662 | fp = FRAME_FP (frame); |
1211c4e4 AC |
663 | i386_frame_init_saved_regs (frame); |
664 | ||
c5aa993b | 665 | for (regnum = 0; regnum < NUM_REGS; regnum++) |
c906108c SS |
666 | { |
667 | CORE_ADDR adr; | |
1211c4e4 | 668 | adr = frame->saved_regs[regnum]; |
c906108c SS |
669 | if (adr) |
670 | { | |
671 | read_memory (adr, regbuf, REGISTER_RAW_SIZE (regnum)); | |
672 | write_register_bytes (REGISTER_BYTE (regnum), regbuf, | |
673 | REGISTER_RAW_SIZE (regnum)); | |
674 | } | |
675 | } | |
676 | write_register (FP_REGNUM, read_memory_integer (fp, 4)); | |
677 | write_register (PC_REGNUM, read_memory_integer (fp + 4, 4)); | |
678 | write_register (SP_REGNUM, fp + 8); | |
679 | flush_cached_frames (); | |
680 | } | |
681 | ||
682 | #ifdef GET_LONGJMP_TARGET | |
683 | ||
684 | /* Figure out where the longjmp will land. Slurp the args out of the stack. | |
685 | We expect the first arg to be a pointer to the jmp_buf structure from which | |
686 | we extract the pc (JB_PC) that we will land at. The pc is copied into PC. | |
687 | This routine returns true on success. */ | |
688 | ||
689 | int | |
fba45db2 | 690 | get_longjmp_target (CORE_ADDR *pc) |
c906108c SS |
691 | { |
692 | char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT]; | |
693 | CORE_ADDR sp, jb_addr; | |
694 | ||
695 | sp = read_register (SP_REGNUM); | |
696 | ||
c5aa993b | 697 | if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack */ |
c906108c SS |
698 | buf, |
699 | TARGET_PTR_BIT / TARGET_CHAR_BIT)) | |
700 | return 0; | |
701 | ||
702 | jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); | |
703 | ||
704 | if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf, | |
705 | TARGET_PTR_BIT / TARGET_CHAR_BIT)) | |
706 | return 0; | |
707 | ||
708 | *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); | |
709 | ||
710 | return 1; | |
711 | } | |
712 | ||
713 | #endif /* GET_LONGJMP_TARGET */ | |
714 | ||
1a309862 MK |
715 | /* These registers are used for returning integers (and on some |
716 | targets also for returning `struct' and `union' values when their | |
ef9dff19 | 717 | size and alignment match an integer type). */ |
1a309862 MK |
718 | #define LOW_RETURN_REGNUM 0 /* %eax */ |
719 | #define HIGH_RETURN_REGNUM 2 /* %edx */ | |
720 | ||
721 | /* Extract from an array REGBUF containing the (raw) register state, a | |
722 | function return value of TYPE, and copy that, in virtual format, | |
723 | into VALBUF. */ | |
724 | ||
c906108c | 725 | void |
1a309862 | 726 | i386_extract_return_value (struct type *type, char *regbuf, char *valbuf) |
c906108c | 727 | { |
1a309862 MK |
728 | int len = TYPE_LENGTH (type); |
729 | ||
c5aa993b | 730 | if (TYPE_CODE_FLT == TYPE_CODE (type)) |
c906108c | 731 | { |
1a309862 MK |
732 | if (NUM_FREGS == 0) |
733 | { | |
734 | warning ("Cannot find floating-point return value."); | |
735 | memset (valbuf, 0, len); | |
ef9dff19 | 736 | return; |
1a309862 MK |
737 | } |
738 | ||
739 | /* Floating-point return values can be found in %st(0). */ | |
740 | if (len == TARGET_LONG_DOUBLE_BIT / TARGET_CHAR_BIT | |
741 | && TARGET_LONG_DOUBLE_FORMAT == &floatformat_i387_ext) | |
742 | { | |
743 | /* Copy straight over, but take care of the padding. */ | |
744 | memcpy (valbuf, ®buf[REGISTER_BYTE (FP0_REGNUM)], | |
745 | FPU_REG_RAW_SIZE); | |
746 | memset (valbuf + FPU_REG_RAW_SIZE, 0, len - FPU_REG_RAW_SIZE); | |
747 | } | |
748 | else | |
749 | { | |
750 | /* Convert the extended floating-point number found in | |
751 | %st(0) to the desired type. This is probably not exactly | |
752 | how it would happen on the target itself, but it is the | |
753 | best we can do. */ | |
754 | DOUBLEST val; | |
755 | floatformat_to_doublest (&floatformat_i387_ext, | |
756 | ®buf[REGISTER_BYTE (FP0_REGNUM)], &val); | |
757 | store_floating (valbuf, TYPE_LENGTH (type), val); | |
758 | } | |
c906108c SS |
759 | } |
760 | else | |
c5aa993b | 761 | { |
d4f3574e SS |
762 | int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM); |
763 | int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM); | |
764 | ||
765 | if (len <= low_size) | |
1a309862 | 766 | memcpy (valbuf, ®buf[REGISTER_BYTE (LOW_RETURN_REGNUM)], len); |
d4f3574e SS |
767 | else if (len <= (low_size + high_size)) |
768 | { | |
769 | memcpy (valbuf, | |
1a309862 | 770 | ®buf[REGISTER_BYTE (LOW_RETURN_REGNUM)], low_size); |
d4f3574e | 771 | memcpy (valbuf + low_size, |
1a309862 | 772 | ®buf[REGISTER_BYTE (HIGH_RETURN_REGNUM)], len - low_size); |
d4f3574e SS |
773 | } |
774 | else | |
8e65ff28 AC |
775 | internal_error (__FILE__, __LINE__, |
776 | "Cannot extract return value of %d bytes long.", len); | |
c906108c SS |
777 | } |
778 | } | |
779 | ||
ef9dff19 MK |
780 | /* Write into the appropriate registers a function return value stored |
781 | in VALBUF of type TYPE, given in virtual format. */ | |
782 | ||
783 | void | |
784 | i386_store_return_value (struct type *type, char *valbuf) | |
785 | { | |
786 | int len = TYPE_LENGTH (type); | |
787 | ||
788 | if (TYPE_CODE_FLT == TYPE_CODE (type)) | |
789 | { | |
790 | if (NUM_FREGS == 0) | |
791 | { | |
792 | warning ("Cannot set floating-point return value."); | |
793 | return; | |
794 | } | |
795 | ||
796 | /* Floating-point return values can be found in %st(0). */ | |
797 | if (len == TARGET_LONG_DOUBLE_BIT / TARGET_CHAR_BIT | |
798 | && TARGET_LONG_DOUBLE_FORMAT == &floatformat_i387_ext) | |
799 | { | |
800 | /* Copy straight over. */ | |
801 | write_register_bytes (REGISTER_BYTE (FP0_REGNUM), valbuf, | |
802 | FPU_REG_RAW_SIZE); | |
803 | } | |
804 | else | |
805 | { | |
806 | char buf[FPU_REG_RAW_SIZE]; | |
807 | DOUBLEST val; | |
808 | ||
809 | /* Convert the value found in VALBUF to the extended | |
810 | floating point format used by the FPU. This is probably | |
811 | not exactly how it would happen on the target itself, but | |
812 | it is the best we can do. */ | |
813 | val = extract_floating (valbuf, TYPE_LENGTH (type)); | |
814 | floatformat_from_doublest (&floatformat_i387_ext, &val, buf); | |
815 | write_register_bytes (REGISTER_BYTE (FP0_REGNUM), buf, | |
816 | FPU_REG_RAW_SIZE); | |
817 | } | |
818 | } | |
819 | else | |
820 | { | |
821 | int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM); | |
822 | int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM); | |
823 | ||
824 | if (len <= low_size) | |
825 | write_register_bytes (REGISTER_BYTE (LOW_RETURN_REGNUM), valbuf, len); | |
826 | else if (len <= (low_size + high_size)) | |
827 | { | |
828 | write_register_bytes (REGISTER_BYTE (LOW_RETURN_REGNUM), | |
829 | valbuf, low_size); | |
830 | write_register_bytes (REGISTER_BYTE (HIGH_RETURN_REGNUM), | |
831 | valbuf + low_size, len - low_size); | |
832 | } | |
833 | else | |
8e65ff28 AC |
834 | internal_error (__FILE__, __LINE__, |
835 | "Cannot store return value of %d bytes long.", len); | |
ef9dff19 MK |
836 | } |
837 | } | |
838 | ||
ac27f131 MK |
839 | /* Convert data from raw format for register REGNUM in buffer FROM to |
840 | virtual format with type TYPE in buffer TO. In principle both | |
841 | formats are identical except that the virtual format has two extra | |
842 | bytes appended that aren't used. We set these to zero. */ | |
843 | ||
844 | void | |
845 | i386_register_convert_to_virtual (int regnum, struct type *type, | |
846 | char *from, char *to) | |
847 | { | |
848 | /* Copy straight over, but take care of the padding. */ | |
849 | memcpy (to, from, FPU_REG_RAW_SIZE); | |
850 | memset (to + FPU_REG_RAW_SIZE, 0, TYPE_LENGTH (type) - FPU_REG_RAW_SIZE); | |
851 | } | |
852 | ||
853 | /* Convert data from virtual format with type TYPE in buffer FROM to | |
854 | raw format for register REGNUM in buffer TO. Simply omit the two | |
855 | unused bytes. */ | |
856 | ||
857 | void | |
858 | i386_register_convert_to_raw (struct type *type, int regnum, | |
859 | char *from, char *to) | |
860 | { | |
861 | memcpy (to, from, FPU_REG_RAW_SIZE); | |
862 | } | |
863 | ||
864 | \f | |
c906108c SS |
865 | #ifdef I386V4_SIGTRAMP_SAVED_PC |
866 | /* Get saved user PC for sigtramp from the pushed ucontext on the stack | |
867 | for all three variants of SVR4 sigtramps. */ | |
868 | ||
869 | CORE_ADDR | |
fba45db2 | 870 | i386v4_sigtramp_saved_pc (struct frame_info *frame) |
c906108c SS |
871 | { |
872 | CORE_ADDR saved_pc_offset = 4; | |
873 | char *name = NULL; | |
874 | ||
875 | find_pc_partial_function (frame->pc, &name, NULL, NULL); | |
876 | if (name) | |
877 | { | |
878 | if (STREQ (name, "_sigreturn")) | |
879 | saved_pc_offset = 132 + 14 * 4; | |
880 | else if (STREQ (name, "_sigacthandler")) | |
881 | saved_pc_offset = 80 + 14 * 4; | |
882 | else if (STREQ (name, "sigvechandler")) | |
883 | saved_pc_offset = 120 + 14 * 4; | |
884 | } | |
885 | ||
886 | if (frame->next) | |
887 | return read_memory_integer (frame->next->frame + saved_pc_offset, 4); | |
888 | return read_memory_integer (read_register (SP_REGNUM) + saved_pc_offset, 4); | |
889 | } | |
890 | #endif /* I386V4_SIGTRAMP_SAVED_PC */ | |
891 | ||
a0b3c4fd | 892 | |
c906108c SS |
893 | #ifdef STATIC_TRANSFORM_NAME |
894 | /* SunPRO encodes the static variables. This is not related to C++ mangling, | |
895 | it is done for C too. */ | |
896 | ||
897 | char * | |
fba45db2 | 898 | sunpro_static_transform_name (char *name) |
c906108c SS |
899 | { |
900 | char *p; | |
901 | if (IS_STATIC_TRANSFORM_NAME (name)) | |
902 | { | |
903 | /* For file-local statics there will be a period, a bunch | |
c5aa993b JM |
904 | of junk (the contents of which match a string given in the |
905 | N_OPT), a period and the name. For function-local statics | |
906 | there will be a bunch of junk (which seems to change the | |
907 | second character from 'A' to 'B'), a period, the name of the | |
908 | function, and the name. So just skip everything before the | |
909 | last period. */ | |
c906108c SS |
910 | p = strrchr (name, '.'); |
911 | if (p != NULL) | |
912 | name = p + 1; | |
913 | } | |
914 | return name; | |
915 | } | |
916 | #endif /* STATIC_TRANSFORM_NAME */ | |
917 | ||
918 | ||
919 | ||
920 | /* Stuff for WIN32 PE style DLL's but is pretty generic really. */ | |
921 | ||
922 | CORE_ADDR | |
fba45db2 | 923 | skip_trampoline_code (CORE_ADDR pc, char *name) |
c906108c | 924 | { |
c5aa993b | 925 | if (pc && read_memory_unsigned_integer (pc, 2) == 0x25ff) /* jmp *(dest) */ |
c906108c | 926 | { |
c5aa993b | 927 | unsigned long indirect = read_memory_unsigned_integer (pc + 2, 4); |
c906108c | 928 | struct minimal_symbol *indsym = |
c5aa993b JM |
929 | indirect ? lookup_minimal_symbol_by_pc (indirect) : 0; |
930 | char *symname = indsym ? SYMBOL_NAME (indsym) : 0; | |
c906108c | 931 | |
c5aa993b | 932 | if (symname) |
c906108c | 933 | { |
c5aa993b JM |
934 | if (strncmp (symname, "__imp_", 6) == 0 |
935 | || strncmp (symname, "_imp_", 5) == 0) | |
c906108c SS |
936 | return name ? 1 : read_memory_unsigned_integer (indirect, 4); |
937 | } | |
938 | } | |
939 | return 0; /* not a trampoline */ | |
940 | } | |
941 | ||
942 | static int | |
fba45db2 | 943 | gdb_print_insn_i386 (bfd_vma memaddr, disassemble_info *info) |
c906108c SS |
944 | { |
945 | if (disassembly_flavor == att_flavor) | |
946 | return print_insn_i386_att (memaddr, info); | |
947 | else if (disassembly_flavor == intel_flavor) | |
948 | return print_insn_i386_intel (memaddr, info); | |
7a292a7a SS |
949 | /* Never reached - disassembly_flavour is always either att_flavor |
950 | or intel_flavor */ | |
e1e9e218 | 951 | internal_error (__FILE__, __LINE__, "failed internal consistency check"); |
7a292a7a SS |
952 | } |
953 | ||
954 | /* If the disassembly mode is intel, we have to also switch the | |
955 | bfd mach_type. This function is run in the set disassembly_flavor | |
956 | command, and does that. */ | |
957 | ||
958 | static void | |
fba45db2 KB |
959 | set_disassembly_flavor_sfunc (char *args, int from_tty, |
960 | struct cmd_list_element *c) | |
7a292a7a SS |
961 | { |
962 | set_disassembly_flavor (); | |
7a292a7a SS |
963 | } |
964 | ||
965 | static void | |
fba45db2 | 966 | set_disassembly_flavor (void) |
7a292a7a SS |
967 | { |
968 | if (disassembly_flavor == att_flavor) | |
969 | set_architecture_from_arch_mach (bfd_arch_i386, bfd_mach_i386_i386); | |
970 | else if (disassembly_flavor == intel_flavor) | |
971 | set_architecture_from_arch_mach (bfd_arch_i386, bfd_mach_i386_i386_intel_syntax); | |
c906108c SS |
972 | } |
973 | ||
2acceee2 | 974 | |
c906108c | 975 | void |
fba45db2 | 976 | _initialize_i386_tdep (void) |
c906108c | 977 | { |
917317f4 JM |
978 | /* Initialize the table saying where each register starts in the |
979 | register file. */ | |
980 | { | |
981 | int i, offset; | |
982 | ||
983 | offset = 0; | |
984 | for (i = 0; i < MAX_NUM_REGS; i++) | |
985 | { | |
986 | i386_register_byte[i] = offset; | |
987 | offset += i386_register_raw_size[i]; | |
988 | } | |
989 | } | |
990 | ||
991 | /* Initialize the table of virtual register sizes. */ | |
992 | { | |
993 | int i; | |
994 | ||
995 | for (i = 0; i < MAX_NUM_REGS; i++) | |
996 | i386_register_virtual_size[i] = TYPE_LENGTH (REGISTER_VIRTUAL_TYPE (i)); | |
997 | } | |
c5aa993b | 998 | |
c906108c SS |
999 | tm_print_insn = gdb_print_insn_i386; |
1000 | tm_print_insn_info.mach = bfd_lookup_arch (bfd_arch_i386, 0)->mach; | |
1001 | ||
1002 | /* Add the variable that controls the disassembly flavor */ | |
917317f4 JM |
1003 | { |
1004 | struct cmd_list_element *new_cmd; | |
7a292a7a | 1005 | |
917317f4 JM |
1006 | new_cmd = add_set_enum_cmd ("disassembly-flavor", no_class, |
1007 | valid_flavors, | |
1ed2a135 | 1008 | &disassembly_flavor, |
917317f4 | 1009 | "Set the disassembly flavor, the valid values are \"att\" and \"intel\", \ |
c906108c | 1010 | and the default value is \"att\".", |
917317f4 JM |
1011 | &setlist); |
1012 | new_cmd->function.sfunc = set_disassembly_flavor_sfunc; | |
1013 | add_show_from_set (new_cmd, &showlist); | |
1014 | } | |
c5aa993b | 1015 | |
7a292a7a SS |
1016 | /* Finally, initialize the disassembly flavor to the default given |
1017 | in the disassembly_flavor variable */ | |
c906108c | 1018 | |
7a292a7a | 1019 | set_disassembly_flavor (); |
c906108c | 1020 | } |