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Changed MMXREG and XMMREG flags to help resolve invalid REX prefix generation for...
[nasm/sigaren-mirror.git] / disasm.c
blobadf3a37a67db8215368b4584b22769795fbbbe03
1 /* disasm.c where all the _work_ gets done in the Netwide Disassembler
2 *
3 * The Netwide Assembler is copyright (C) 1996 Simon Tatham and
4 * Julian Hall. All rights reserved. The software is
5 * redistributable under the licence given in the file "Licence"
6 * distributed in the NASM archive.
7 *
8 * initial version 27/iii/95 by Simon Tatham
9 */
10
11 #include <stdio.h>
12 #include <string.h>
13 #include <inttypes.h>
14
15 #include "nasm.h"
16 #include "disasm.h"
17 #include "sync.h"
18 #include "insns.h"
19
20 #include "names.c"
21
22 extern struct itemplate **itable[];
23
24 /*
25 * Flags that go into the `segment' field of `insn' structures
26 * during disassembly.
27 */
28 #define SEG_RELATIVE 1
29 #define SEG_32BIT 2
30 #define SEG_RMREG 4
31 #define SEG_DISP8 8
32 #define SEG_DISP16 16
33 #define SEG_DISP32 32
34 #define SEG_NODISP 64
35 #define SEG_SIGNED 128
36 #define SEG_64BIT 256
37
38 #include "regdis.c"
39
40 #define getu8(x) (*(uint8_t *)(x))
41 #if defined(__i386__) || defined(__x86_64__)
42 /* Littleendian CPU which can handle unaligned references */
43 #define getu16(x) (*(uint16_t *)(x))
44 #define getu32(x) (*(uint32_t *)(x))
45 #define getu64(x) (*(uint64_t *)(x))
46 #else
47 static uint16_t getu16(uint8_t *data)
48 {
49 return (uint16_t)data[0] + ((uint16_t)data[1] << 8);
50 }
51 static uint32_t getu32(uint8_t *data)
52 {
53 return (uint32_t)getu16(data) + ((uint32_t)getu16(data+2) << 16);
54 }
55 static uint64_t getu64(uint8_t *data)
56 {
57 return (uint64_t)getu32(data) + ((uint64_t)getu32(data+4) << 32);
58 }
59 #endif
60
61 #define gets8(x) ((int8_t)getu8(x))
62 #define gets16(x) ((int16_t)getu16(x))
63 #define gets32(x) ((int32_t)getu32(x))
64 #define gets64(x) ((int64_t)getu64(x))
65
66 /* Important: regval must already have been adjusted for rex extensions */
67 static int whichreg(int32_t regflags, int regval, int rex)
68 {
69 if (!(REG_AL & ~regflags))
70 return R_AL;
71 if (!(REG_AX & ~regflags))
72 return R_AX;
73 if (!(REG_EAX & ~regflags))
74 return R_EAX;
75 if (!(REG_RAX & ~regflags))
76 return R_RAX;
77 if (!(REG_DL & ~regflags))
78 return R_DL;
79 if (!(REG_DX & ~regflags))
80 return R_DX;
81 if (!(REG_EDX & ~regflags))
82 return R_EDX;
83 if (!(REG_RDX & ~regflags))
84 return R_RDX;
85 if (!(REG_CL & ~regflags))
86 return R_CL;
87 if (!(REG_CX & ~regflags))
88 return R_CX;
89 if (!(REG_ECX & ~regflags))
90 return R_ECX;
91 if (!(REG_RCX & ~regflags))
92 return R_RCX;
93 if (!(FPU0 & ~regflags))
94 return R_ST0;
95 if (!(REG_CS & ~regflags))
96 return (regval == 1) ? R_CS : 0;
97 if (!(REG_DESS & ~regflags))
98 return (regval == 0 || regval == 2
99 || regval == 3 ? rd_sreg[regval] : 0);
100 if (!(REG_FSGS & ~regflags))
101 return (regval == 4 || regval == 5 ? rd_sreg[regval] : 0);
102 if (!(REG_SEG67 & ~regflags))
103 return (regval == 6 || regval == 7 ? rd_sreg[regval] : 0);
104
105 /* All the entries below look up regval in an 16-entry array */
106 if (regval < 0 || regval > 15)
107 return 0;
108
109 if (!((REGMEM | BITS8) & ~regflags)) {
110 if (rex & REX_P)
111 return rd_reg8_rex[regval];
112 else
113 return rd_reg8[regval];
114 }
115 if (!((REGMEM | BITS16) & ~regflags))
116 return rd_reg16[regval];
117 if (!((REGMEM | BITS32) & ~regflags))
118 return rd_reg32[regval];
119 if (!((REGMEM | BITS64) & ~regflags))
120 return rd_reg64[regval];
121 if (!(REG_SREG & ~regflags))
122 return rd_sreg[regval & 7]; /* Ignore REX */
123 if (!(REG_CREG & ~regflags))
124 return rd_creg[regval];
125 if (!(REG_DREG & ~regflags))
126 return rd_dreg[regval];
127 if (!(REG_TREG & ~regflags)) {
128 if (rex & REX_P)
129 return 0; /* TR registers are ill-defined with rex */
130 return rd_treg[regval];
131 }
132 if (!(FPUREG & ~regflags))
133 return rd_fpureg[regval & 7]; /* Ignore REX */
134 if (!(MMXREG & ~regflags))
135 return rd_mmxreg[regval & 7]; /* Ignore REX */
136 if (!(XMMREG & ~regflags))
137 return rd_xmmreg[regval];
138
139 return 0;
140 }
141
142 static const char *whichcond(int condval)
143 {
144 static int conds[] = {
145 C_O, C_NO, C_C, C_NC, C_Z, C_NZ, C_NA, C_A,
146 C_S, C_NS, C_PE, C_PO, C_L, C_NL, C_NG, C_G
147 };
148 return conditions[conds[condval]];
149 }
150
151 /*
152 * Process an effective address (ModRM) specification.
153 */
154 static uint8_t *do_ea(uint8_t *data, int modrm, int asize,
155 int segsize, operand * op, int rex)
156 {
157 int mod, rm, scale, index, base;
158
159 mod = (modrm >> 6) & 03;
160 rm = modrm & 07;
161
162 if (mod == 3) { /* pure register version */
163 op->basereg = rm+(rex & REX_B ? 8 : 0);
164 op->segment |= SEG_RMREG;
165 return data;
166 }
167
168 op->addr_size = 0;
169
170 if (asize == 16) {
171 /*
172 * <mod> specifies the displacement size (none, byte or
173 * word), and <rm> specifies the register combination.
174 * Exception: mod=0,rm=6 does not specify [BP] as one might
175 * expect, but instead specifies [disp16].
176 */
177 op->indexreg = op->basereg = -1;
178 op->scale = 1; /* always, in 16 bits */
179 switch (rm) {
180 case 0:
181 op->basereg = R_BX;
182 op->indexreg = R_SI;
183 break;
184 case 1:
185 op->basereg = R_BX;
186 op->indexreg = R_DI;
187 break;
188 case 2:
189 op->basereg = R_BP;
190 op->indexreg = R_SI;
191 break;
192 case 3:
193 op->basereg = R_BP;
194 op->indexreg = R_DI;
195 break;
196 case 4:
197 op->basereg = R_SI;
198 break;
199 case 5:
200 op->basereg = R_DI;
201 break;
202 case 6:
203 op->basereg = R_BP;
204 break;
205 case 7:
206 op->basereg = R_BX;
207 break;
208 }
209 if (rm == 6 && mod == 0) { /* special case */
210 op->basereg = -1;
211 if (segsize != 16)
212 op->addr_size = 16;
213 mod = 2; /* fake disp16 */
214 }
215 switch (mod) {
216 case 0:
217 op->segment |= SEG_NODISP;
218 break;
219 case 1:
220 op->segment |= SEG_DISP8;
221 op->offset = (int8_t)*data++;
222 break;
223 case 2:
224 op->segment |= SEG_DISP16;
225 op->offset = *data++;
226 op->offset |= ((unsigned)*data++) << 8;
227 break;
228 }
229 return data;
230 } else {
231 /*
232 * Once again, <mod> specifies displacement size (this time
233 * none, byte or *dword*), while <rm> specifies the base
234 * register. Again, [EBP] is missing, replaced by a pure
235 * disp32 (this time that's mod=0,rm=*5*) in 32-bit mode,
236 * and RIP-relative addressing in 64-bit mode.
237 *
238 * However, rm=4
239 * indicates not a single base register, but instead the
240 * presence of a SIB byte...
241 */
242 int a64 = asize == 64;
243
244 op->indexreg = -1;
245
246 if (a64)
247 op->basereg = rd_reg64[rm | ((rex & REX_B) ? 8 : 0)];
248 else
249 op->basereg = rd_reg32[rm | ((rex & REX_B) ? 8 : 0)];
250
251 if (rm == 5 && mod == 0) {
252 if (segsize == 64) {
253 op->basereg = R_RIP;
254 op->segment |= SEG_RELATIVE;
255 mod = 2; /* fake disp32 */
256 } else {
257 op->basereg = -1;
258 if (segsize != 32)
259 op->addr_size = 32;
260 mod = 2; /* fake disp32 */
261 }
262 }
263
264 if (rm == 4) { /* process SIB */
265 scale = (*data >> 6) & 03;
266 index = (*data >> 3) & 07;
267 base = *data & 07;
268 data++;
269
270 op->scale = 1 << scale;
271
272 if (index == 4)
273 op->indexreg = -1; /* ESP/RSP/R12 cannot be an index */
274 else if (a64)
275 op->indexreg = rd_reg64[index | ((rex & REX_X) ? 8 : 0)];
276 else
277 op->indexreg = rd_reg64[index | ((rex & REX_X) ? 8 : 0)];
278
279 if (base == 5 && mod == 0) {
280 op->basereg = -1;
281 mod = 2; /* Fake disp32 */
282 } else if (a64)
283 op->basereg = rd_reg64[base | ((rex & REX_B) ? 8 : 0)];
284 else
285 op->basereg = rd_reg32[base | ((rex & REX_B) ? 8 : 0)];
286 }
287
288 switch (mod) {
289 case 0:
290 op->segment |= SEG_NODISP;
291 break;
292 case 1:
293 op->segment |= SEG_DISP8;
294 op->offset = gets8(data);
295 data++;
296 break;
297 case 2:
298 op->segment |= SEG_DISP32;
299 op->offset = getu32(data);
300 data += 4;
301 break;
302 }
303 return data;
304 }
305 }
306
307 /*
308 * Determine whether the instruction template in t corresponds to the data
309 * stream in data. Return the number of bytes matched if so.
310 */
311 static int matches(struct itemplate *t, uint8_t *data, int asize,
312 int osize, int segsize, int rep, insn * ins,
313 int rex, int *rexout, int lock)
314 {
315 uint8_t *r = (uint8_t *)(t->code);
316 uint8_t *origdata = data;
317 int a_used = FALSE, o_used = FALSE;
318 int drep = 0;
319
320 *rexout = rex;
321
322 if (t->flags & (segsize == 64 ? IF_NOLONG : IF_LONG))
323 return FALSE;
324
325 if (rep == 0xF2)
326 drep = P_REPNE;
327 else if (rep == 0xF3)
328 drep = P_REP;
329
330 while (*r) {
331 int c = *r++;
332
333 /* FIX: change this into a switch */
334 if (c >= 01 && c <= 03) {
335 while (c--)
336 if (*r++ != *data++)
337 return FALSE;
338 } else if (c == 04) {
339 switch (*data++) {
340 case 0x07:
341 ins->oprs[0].basereg = 0;
342 break;
343 case 0x17:
344 ins->oprs[0].basereg = 2;
345 break;
346 case 0x1F:
347 ins->oprs[0].basereg = 3;
348 break;
349 default:
350 return FALSE;
351 }
352 } else if (c == 05) {
353 switch (*data++) {
354 case 0xA1:
355 ins->oprs[0].basereg = 4;
356 break;
357 case 0xA9:
358 ins->oprs[0].basereg = 5;
359 break;
360 default:
361 return FALSE;
362 }
363 } else if (c == 06) {
364 switch (*data++) {
365 case 0x06:
366 ins->oprs[0].basereg = 0;
367 break;
368 case 0x0E:
369 ins->oprs[0].basereg = 1;
370 break;
371 case 0x16:
372 ins->oprs[0].basereg = 2;
373 break;
374 case 0x1E:
375 ins->oprs[0].basereg = 3;
376 break;
377 default:
378 return FALSE;
379 }
380 } else if (c == 07) {
381 switch (*data++) {
382 case 0xA0:
383 ins->oprs[0].basereg = 4;
384 break;
385 case 0xA8:
386 ins->oprs[0].basereg = 5;
387 break;
388 default:
389 return FALSE;
390 }
391 } else if (c >= 010 && c <= 012) {
392 int t = *r++, d = *data++;
393 if (d < t || d > t + 7)
394 return FALSE;
395 else {
396 ins->oprs[c - 010].basereg = (d-t)+(rex & REX_B ? 8 : 0);
397 ins->oprs[c - 010].segment |= SEG_RMREG;
398 }
399 } else if (c == 017) {
400 if (*data++)
401 return FALSE;
402 } else if (c >= 014 && c <= 016) {
403 ins->oprs[c - 014].offset = (int8_t)*data++;
404 ins->oprs[c - 014].segment |= SEG_SIGNED;
405 } else if (c >= 020 && c <= 022) {
406 ins->oprs[c - 020].offset = *data++;
407 } else if (c >= 024 && c <= 026) {
408 ins->oprs[c - 024].offset = *data++;
409 } else if (c >= 030 && c <= 032) {
410 ins->oprs[c - 030].offset = getu16(data);
411 data += 2;
412 } else if (c >= 034 && c <= 036) {
413 if (osize == 32) {
414 ins->oprs[c - 034].offset = getu32(data);
415 data += 4;
416 } else {
417 ins->oprs[c - 034].offset = getu16(data);
418 data += 2;
419 }
420 if (segsize != asize)
421 ins->oprs[c - 034].addr_size = asize;
422 } else if (c >= 040 && c <= 042) {
423 ins->oprs[c - 040].offset = getu32(data);
424 data += 4;
425 } else if (c >= 044 && c <= 046) {
426 switch (asize) {
427 case 16:
428 ins->oprs[c - 044].offset = getu16(data);
429 data += 2;
430 break;
431 case 32:
432 ins->oprs[c - 044].offset = getu32(data);
433 data += 4;
434 break;
435 case 64:
436 ins->oprs[c - 044].offset = getu64(data);
437 data += 8;
438 break;
439 }
440 if (segsize != asize)
441 ins->oprs[c - 044].addr_size = asize;
442 } else if (c >= 050 && c <= 052) {
443 ins->oprs[c - 050].offset = gets8(data++);
444 ins->oprs[c - 050].segment |= SEG_RELATIVE;
445 } else if (c >= 054 && c <= 056) {
446 ins->oprs[c - 054].offset = getu64(data);
447 data += 8;
448 } else if (c >= 060 && c <= 062) {
449 ins->oprs[c - 060].offset = gets16(data);
450 data += 2;
451 ins->oprs[c - 060].segment |= SEG_RELATIVE;
452 ins->oprs[c - 060].segment &= ~SEG_32BIT;
453 } else if (c >= 064 && c <= 066) {
454 if (osize == 16) {
455 ins->oprs[c - 064].offset = getu16(data);
456 data += 2;
457 ins->oprs[c - 064].segment &= ~(SEG_32BIT|SEG_64BIT);
458 } else if (osize == 32) {
459 ins->oprs[c - 064].offset = getu32(data);
460 data += 4;
461 ins->oprs[c - 064].segment &= ~SEG_64BIT;
462 ins->oprs[c - 064].segment |= SEG_32BIT;
463 }
464 if (segsize != osize) {
465 ins->oprs[c - 064].type =
466 (ins->oprs[c - 064].type & ~SIZE_MASK)
467 | ((osize == 16) ? BITS16 : BITS32);
468 }
469 } else if (c >= 070 && c <= 072) {
470 ins->oprs[c - 070].offset = getu32(data);
471 data += 4;
472 ins->oprs[c - 070].segment |= SEG_32BIT | SEG_RELATIVE;
473 } else if (c >= 0100 && c < 0130) {
474 int modrm = *data++;
475 ins->oprs[c & 07].basereg = ((modrm >> 3)&7)+(rex & REX_R ? 8 : 0);
476 ins->oprs[c & 07].segment |= SEG_RMREG;
477 data = do_ea(data, modrm, asize, segsize,
478 &ins->oprs[(c >> 3) & 07], rex);
479 } else if (c >= 0130 && c <= 0132) {
480 ins->oprs[c - 0130].offset = getu16(data);
481 data += 2;
482 } else if (c >= 0140 && c <= 0142) {
483 ins->oprs[c - 0140].offset = getu32(data);
484 data += 4;
485 } else if (c >= 0200 && c <= 0277) {
486 int modrm = *data++;
487 if (((modrm >> 3) & 07) != (c & 07))
488 return FALSE; /* spare field doesn't match up */
489 data = do_ea(data, modrm, asize, segsize,
490 &ins->oprs[(c >> 3) & 07], rex);
491 } else if (c >= 0300 && c <= 0302) {
492 a_used = TRUE;
493 } else if (c == 0310) {
494 if (asize != 16)
495 return FALSE;
496 else
497 a_used = TRUE;
498 } else if (c == 0311) {
499 if (asize == 16)
500 return FALSE;
501 else
502 a_used = TRUE;
503 } else if (c == 0312) {
504 if (asize != segsize)
505 return FALSE;
506 else
507 a_used = TRUE;
508 } else if (c == 0313) {
509 if (asize != 64)
510 return FALSE;
511 else
512 a_used = TRUE;
513 } else if (c == 0320) {
514 if (osize != 16)
515 return FALSE;
516 else
517 o_used = TRUE;
518 } else if (c == 0321) {
519 if (osize != 32)
520 return FALSE;
521 else
522 o_used = TRUE;
523 } else if (c == 0322) {
524 if (osize != (segsize == 16) ? 16 : 32)
525 return FALSE;
526 else
527 o_used = TRUE;
528 } else if (c == 0323) {
529 rex |= REX_W; /* 64-bit only instruction */
530 osize = 64;
531 } else if (c == 0324) {
532 if (!(rex & (REX_P|REX_W)) || osize != 64)
533 return FALSE;
534 } else if (c == 0330) {
535 int t = *r++, d = *data++;
536 if (d < t || d > t + 15)
537 return FALSE;
538 else
539 ins->condition = d - t;
540 } else if (c == 0331) {
541 if (rep)
542 return FALSE;
543 } else if (c == 0332) {
544 if (drep == P_REP)
545 drep = P_REPE;
546 } else if (c == 0333) {
547 if (rep != 0xF3)
548 return FALSE;
549 drep = 0;
550 } else if (c == 0334) {
551 if (lock) {
552 rex |= REX_R;
553 lock = 0;
554 }
555 }
556 }
557
558 /*
559 * Check for unused rep or a/o prefixes.
560 */
561 ins->nprefix = 0;
562 if (lock)
563 ins->prefixes[ins->nprefix++] = P_LOCK;
564 if (drep)
565 ins->prefixes[ins->nprefix++] = drep;
566 if (!a_used && asize != segsize)
567 ins->prefixes[ins->nprefix++] = asize == 16 ? P_A16 : P_A32;
568 if (!o_used && osize == ((segsize == 16) ? 32 : 16))
569 ins->prefixes[ins->nprefix++] = osize == 16 ? P_O16 : P_O32;
570
571 /* Fix: check for redundant REX prefixes */
572
573 *rexout = rex;
574 return data - origdata;
575 }
576
577 int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize,
578 int32_t offset, int autosync, uint32_t prefer)
579 {
580 struct itemplate **p, **best_p;
581 int length, best_length = 0;
582 char *segover;
583 int rep, lock, asize, osize, i, slen, colon, rex, rexout, best_rex;
584 uint8_t *origdata;
585 int works;
586 insn tmp_ins, ins;
587 uint32_t goodness, best;
588
589 /*
590 * Scan for prefixes.
591 */
592 asize = segsize;
593 osize = (segsize == 64) ? 32 : segsize;
594 rex = 0;
595 segover = NULL;
596 rep = lock = 0;
597 origdata = data;
598 for (;;) {
599 if (*data == 0xF3 || *data == 0xF2)
600 rep = *data++;
601 else if (*data == 0xF0)
602 lock = *data++;
603 else if (*data == 0x2E)
604 segover = "cs", data++;
605 else if (*data == 0x36)
606 segover = "ss", data++;
607 else if (*data == 0x3E)
608 segover = "ds", data++;
609 else if (*data == 0x26)
610 segover = "es", data++;
611 else if (*data == 0x64)
612 segover = "fs", data++;
613 else if (*data == 0x65)
614 segover = "gs", data++;
615 else if (*data == 0x66) {
616 osize = (segsize == 16) ? 32 : 16;
617 data++;
618 } else if (*data == 0x67) {
619 asize = (segsize == 32) ? 16 : 32;
620 data++;
621 } else if (segsize == 64 && (*data & 0xf0) == REX_P) {
622 rex = *data++;
623 if (rex & REX_W)
624 osize = 64;
625 break; /* REX is always the last prefix */
626 } else {
627 break;
628 }
629 }
630
631 tmp_ins.oprs[0].segment = tmp_ins.oprs[1].segment =
632 tmp_ins.oprs[2].segment =
633 tmp_ins.oprs[0].addr_size = tmp_ins.oprs[1].addr_size =
634 tmp_ins.oprs[2].addr_size = (segsize == 64 ? SEG_64BIT :
635 segsize == 32 ? SEG_32BIT : 0);
636 tmp_ins.condition = -1;
637 best = -1; /* Worst possible */
638 best_p = NULL;
639 best_rex = 0;
640 for (p = itable[*data]; *p; p++) {
641 if ((length = matches(*p, data, asize, osize, segsize, rep,
642 &tmp_ins, rex, &rexout, lock))) {
643 works = TRUE;
644 /*
645 * Final check to make sure the types of r/m match up.
646 * XXX: Need to make sure this is actually correct.
647 */
648 for (i = 0; i < (*p)->operands; i++) {
649 if (
650 /* If it's a mem-only EA but we have a register, die. */
651 ((tmp_ins.oprs[i].segment & SEG_RMREG) &&
652 !(MEMORY & ~(*p)->opd[i])) ||
653 /* If it's a reg-only EA but we have a memory ref, die. */
654 (!(tmp_ins.oprs[i].segment & SEG_RMREG) &&
655 !(REG_EA & ~(*p)->opd[i]) &&
656 !((*p)->opd[i] & REG_SMASK)) ||
657 /* Register type mismatch (eg FS vs REG_DESS): die. */
658 ((((*p)->opd[i] & (REGISTER | FPUREG)) ||
659 (tmp_ins.oprs[i].segment & SEG_RMREG)) &&
660 !whichreg((*p)->opd[i],
661 tmp_ins.oprs[i].basereg, rexout))) {
662 works = FALSE;
663 break;
664 }
665 }
666
667 if (works) {
668 goodness = ((*p)->flags & IF_PFMASK) ^ prefer;
669 if (goodness < best) {
670 /* This is the best one found so far */
671 best = goodness;
672 best_p = p;
673 best_length = length;
674 ins = tmp_ins;
675 best_rex = rexout;
676 }
677 }
678 }
679 }
680
681 if (!best_p)
682 return 0; /* no instruction was matched */
683
684 /* Pick the best match */
685 p = best_p;
686 length = best_length;
687 rex = best_rex;
688 if (best_rex & REX_W)
689 osize = 64;
690
691 slen = 0;
692
693 /* TODO: snprintf returns the value that the string would have if
694 * the buffer were long enough, and not the actual length of
695 * the returned string, so each instance of using the return
696 * value of snprintf should actually be checked to assure that
697 * the return value is "sane." Maybe a macro wrapper could
698 * be used for that purpose.
699 */
700 for (i = 0; i < ins.nprefix; i++)
701 switch (ins.prefixes[i]) {
702 case P_LOCK:
703 slen += snprintf(output + slen, outbufsize - slen, "lock ");
704 break;
705 case P_REP:
706 slen += snprintf(output + slen, outbufsize - slen, "rep ");
707 break;
708 case P_REPE:
709 slen += snprintf(output + slen, outbufsize - slen, "repe ");
710 break;
711 case P_REPNE:
712 slen += snprintf(output + slen, outbufsize - slen, "repne ");
713 break;
714 case P_A16:
715 slen += snprintf(output + slen, outbufsize - slen, "a16 ");
716 break;
717 case P_A32:
718 slen += snprintf(output + slen, outbufsize - slen, "a32 ");
719 break;
720 case P_O16:
721 slen += snprintf(output + slen, outbufsize - slen, "o16 ");
722 break;
723 case P_O32:
724 slen += snprintf(output + slen, outbufsize - slen, "o32 ");
725 break;
726 }
727
728 for (i = 0; i < elements(ico); i++)
729 if ((*p)->opcode == ico[i]) {
730 slen +=
731 snprintf(output + slen, outbufsize - slen, "%s%s", icn[i],
732 whichcond(ins.condition));
733 break;
734 }
735 if (i >= elements(ico))
736 slen +=
737 snprintf(output + slen, outbufsize - slen, "%s",
738 insn_names[(*p)->opcode]);
739 colon = FALSE;
740 length += data - origdata; /* fix up for prefixes */
741 for (i = 0; i < (*p)->operands; i++) {
742 output[slen++] = (colon ? ':' : i == 0 ? ' ' : ',');
743
744 if (ins.oprs[i].segment & SEG_RELATIVE) {
745 ins.oprs[i].offset += offset + length;
746 /*
747 * sort out wraparound
748 */
749 if (!(ins.oprs[i].segment & (SEG_32BIT|SEG_64BIT)))
750 ins.oprs[i].offset &= 0xffff;
751 /*
752 * add sync marker, if autosync is on
753 */
754 if (autosync)
755 add_sync(ins.oprs[i].offset, 0L);
756 }
757
758 if ((*p)->opd[i] & COLON)
759 colon = TRUE;
760 else
761 colon = FALSE;
762
763 if (((*p)->opd[i] & (REGISTER | FPUREG)) ||
764 (ins.oprs[i].segment & SEG_RMREG)) {
765 ins.oprs[i].basereg = whichreg((*p)->opd[i],
766 ins.oprs[i].basereg, rex);
767 if ((*p)->opd[i] & TO)
768 slen += snprintf(output + slen, outbufsize - slen, "to ");
769 slen += snprintf(output + slen, outbufsize - slen, "%s",
770 reg_names[ins.oprs[i].basereg -
771 EXPR_REG_START]);
772 } else if (!(UNITY & ~(*p)->opd[i])) {
773 output[slen++] = '1';
774 } else if ((*p)->opd[i] & IMMEDIATE) {
775 if ((*p)->opd[i] & BITS8) {
776 slen +=
777 snprintf(output + slen, outbufsize - slen, "byte ");
778 if (ins.oprs[i].segment & SEG_SIGNED) {
779 if (ins.oprs[i].offset < 0) {
780 ins.oprs[i].offset *= -1;
781 output[slen++] = '-';
782 } else
783 output[slen++] = '+';
784 }
785 } else if ((*p)->opd[i] & BITS16) {
786 slen +=
787 snprintf(output + slen, outbufsize - slen, "word ");
788 } else if ((*p)->opd[i] & BITS32) {
789 slen +=
790 snprintf(output + slen, outbufsize - slen, "dword ");
791 } else if ((*p)->opd[i] & BITS64) {
792 slen +=
793 snprintf(output + slen, outbufsize - slen, "qword ");
794 } else if ((*p)->opd[i] & NEAR) {
795 slen +=
796 snprintf(output + slen, outbufsize - slen, "near ");
797 } else if ((*p)->opd[i] & SHORT) {
798 slen +=
799 snprintf(output + slen, outbufsize - slen, "short ");
800 }
801 slen +=
802 snprintf(output + slen, outbufsize - slen, "0x%"PRIx64"",
803 ins.oprs[i].offset);
804 } else if (!(MEM_OFFS & ~(*p)->opd[i])) {
805 slen +=
806 snprintf(output + slen, outbufsize - slen, "[%s%s%s0x%"PRIx64"]",
807 ((const char*)segover ? (const char*)segover : ""), /* placate type mistmatch warning */
808 ((const char*)segover ? ":" : ""), /* by using (const char*) instead of uint8_t* */
809 (ins.oprs[i].addr_size ==
810 32 ? "dword " : ins.oprs[i].addr_size ==
811 16 ? "word " : ""), ins.oprs[i].offset);
812 segover = NULL;
813 } else if (!(REGMEM & ~(*p)->opd[i])) {
814 int started = FALSE;
815 if ((*p)->opd[i] & BITS8)
816 slen +=
817 snprintf(output + slen, outbufsize - slen, "byte ");
818 if ((*p)->opd[i] & BITS16)
819 slen +=
820 snprintf(output + slen, outbufsize - slen, "word ");
821 if ((*p)->opd[i] & BITS32)
822 slen +=
823 snprintf(output + slen, outbufsize - slen, "dword ");
824 if ((*p)->opd[i] & BITS64)
825 slen +=
826 snprintf(output + slen, outbufsize - slen, "qword ");
827 if ((*p)->opd[i] & BITS80)
828 slen +=
829 snprintf(output + slen, outbufsize - slen, "tword ");
830 if ((*p)->opd[i] & FAR)
831 slen += snprintf(output + slen, outbufsize - slen, "far ");
832 if ((*p)->opd[i] & NEAR)
833 slen +=
834 snprintf(output + slen, outbufsize - slen, "near ");
835 output[slen++] = '[';
836 if (ins.oprs[i].addr_size)
837 slen += snprintf(output + slen, outbufsize - slen, "%s",
838 (ins.oprs[i].addr_size == 64 ? "qword " :
839 ins.oprs[i].addr_size == 32 ? "dword " :
840 ins.oprs[i].addr_size == 16 ? "word " :
841 ""));
842 if (segover) {
843 slen +=
844 snprintf(output + slen, outbufsize - slen, "%s:",
845 segover);
846 segover = NULL;
847 }
848 if (ins.oprs[i].basereg != -1) {
849 slen += snprintf(output + slen, outbufsize - slen, "%s",
850 reg_names[(ins.oprs[i].basereg -
851 EXPR_REG_START)]);
852 started = TRUE;
853 }
854 if (ins.oprs[i].indexreg != -1) {
855 if (started)
856 output[slen++] = '+';
857 slen += snprintf(output + slen, outbufsize - slen, "%s",
858 reg_names[(ins.oprs[i].indexreg -
859 EXPR_REG_START)]);
860 if (ins.oprs[i].scale > 1)
861 slen +=
862 snprintf(output + slen, outbufsize - slen, "*%d",
863 ins.oprs[i].scale);
864 started = TRUE;
865 }
866 if (ins.oprs[i].segment & SEG_DISP8) {
867 int minus = 0;
868 int8_t offset = ins.oprs[i].offset;
869 if (offset < 0) {
870 minus = 1;
871 offset = -offset;
872 }
873 slen +=
874 snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx8"",
875 minus ? "-" : "+", offset);
876 } else if (ins.oprs[i].segment & SEG_DISP16) {
877 int minus = 0;
878 int16_t offset = ins.oprs[i].offset;
879 if (offset < 0) {
880 minus = 1;
881 offset = -offset;
882 }
883 slen +=
884 snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx16"",
885 minus ? "-" : started ? "+" : "", offset);
886 } else if (ins.oprs[i].segment & SEG_DISP32) {
887 char *prefix = "";
888 int32_t offset = ins.oprs[i].offset;
889 if (ins.oprs[i].basereg == R_RIP) {
890 prefix = ":";
891 } else if (offset < 0) {
892 offset = -offset;
893 prefix = "-";
894 } else {
895 prefix = started ? "+" : "";
896 }
897 slen +=
898 snprintf(output + slen, outbufsize - slen,
899 "%s0x%"PRIx32"", prefix, offset);
900 }
901 output[slen++] = ']';
902 } else {
903 slen +=
904 snprintf(output + slen, outbufsize - slen, "<operand%d>",
905 i);
906 }
907 }
908 output[slen] = '\0';
909 if (segover) { /* unused segment override */
910 char *p = output;
911 int count = slen + 1;
912 while (count--)
913 p[count + 3] = p[count];
914 strncpy(output, segover, 2);
915 output[2] = ' ';
916 }
917 return length;
918 }
919
920 int32_t eatbyte(uint8_t *data, char *output, int outbufsize)
921 {
922 snprintf(output, outbufsize, "db 0x%02X", *data);
923 return 1;
924 }
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