1 /* ----------------------------------------------------------------------- *
3 * Copyright 1996-2012 The NASM Authors - All Rights Reserved
4 * See the file AUTHORS included with the NASM distribution for
5 * the specific copyright holders.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following
11 * * Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * * Redistributions in binary form must reproduce the above
14 * copyright notice, this list of conditions and the following
15 * disclaimer in the documentation and/or other materials provided
16 * with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
19 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
20 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
22 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
29 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
30 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 * ----------------------------------------------------------------------- */
35 * disasm.c where all the _work_ gets done in the Netwide Disassembler
53 * Flags that go into the `segment' field of `insn' structures
56 #define SEG_RELATIVE 1
63 #define SEG_SIGNED 128
70 uint8_t osize; /* Operand size */
71 uint8_t asize; /* Address size */
72 uint8_t osp; /* Operand size prefix present */
73 uint8_t asp; /* Address size prefix present */
74 uint8_t rep; /* Rep prefix present */
75 uint8_t seg; /* Segment override prefix present */
76 uint8_t wait; /* WAIT "prefix" present */
77 uint8_t lock; /* Lock prefix present */
78 uint8_t vex[3]; /* VEX prefix present */
79 uint8_t vex_c; /* VEX "class" (VEX, XOP, ...) */
80 uint8_t vex_m; /* VEX.M field */
82 uint8_t vex_lp; /* VEX.LP fields */
83 uint32_t rex; /* REX prefix present */
86 #define getu8(x) (*(uint8_t *)(x))
88 /* Littleendian CPU which can handle unaligned references */
89 #define getu16(x) (*(uint16_t *)(x))
90 #define getu32(x) (*(uint32_t *)(x))
91 #define getu64(x) (*(uint64_t *)(x))
93 static uint16_t getu16(uint8_t *data)
95 return (uint16_t)data[0] + ((uint16_t)data[1] << 8);
97 static uint32_t getu32(uint8_t *data)
99 return (uint32_t)getu16(data) + ((uint32_t)getu16(data+2) << 16);
101 static uint64_t getu64(uint8_t *data)
103 return (uint64_t)getu32(data) + ((uint64_t)getu32(data+4) << 32);
107 #define gets8(x) ((int8_t)getu8(x))
108 #define gets16(x) ((int16_t)getu16(x))
109 #define gets32(x) ((int32_t)getu32(x))
110 #define gets64(x) ((int64_t)getu64(x))
112 /* Important: regval must already have been adjusted for rex extensions */
113 static enum reg_enum whichreg(opflags_t regflags, int regval, int rex)
115 if (!(regflags & (REGISTER|REGMEM)))
116 return 0; /* Registers not permissible?! */
118 regflags |= REGISTER;
120 if (!(REG_AL & ~regflags))
122 if (!(REG_AX & ~regflags))
124 if (!(REG_EAX & ~regflags))
126 if (!(REG_RAX & ~regflags))
128 if (!(REG_DL & ~regflags))
130 if (!(REG_DX & ~regflags))
132 if (!(REG_EDX & ~regflags))
134 if (!(REG_RDX & ~regflags))
136 if (!(REG_CL & ~regflags))
138 if (!(REG_CX & ~regflags))
140 if (!(REG_ECX & ~regflags))
142 if (!(REG_RCX & ~regflags))
144 if (!(FPU0 & ~regflags))
146 if (!(XMM0 & ~regflags))
148 if (!(YMM0 & ~regflags))
150 if (!(REG_CS & ~regflags))
151 return (regval == 1) ? R_CS : 0;
152 if (!(REG_DESS & ~regflags))
153 return (regval == 0 || regval == 2
154 || regval == 3 ? nasm_rd_sreg[regval] : 0);
155 if (!(REG_FSGS & ~regflags))
156 return (regval == 4 || regval == 5 ? nasm_rd_sreg[regval] : 0);
157 if (!(REG_SEG67 & ~regflags))
158 return (regval == 6 || regval == 7 ? nasm_rd_sreg[regval] : 0);
160 /* All the entries below look up regval in an 16-entry array */
161 if (regval < 0 || regval > 15)
164 if (!(REG8 & ~regflags)) {
165 if (rex & (REX_P|REX_NH))
166 return nasm_rd_reg8_rex[regval];
168 return nasm_rd_reg8[regval];
170 if (!(REG16 & ~regflags))
171 return nasm_rd_reg16[regval];
172 if (!(REG32 & ~regflags))
173 return nasm_rd_reg32[regval];
174 if (!(REG64 & ~regflags))
175 return nasm_rd_reg64[regval];
176 if (!(REG_SREG & ~regflags))
177 return nasm_rd_sreg[regval & 7]; /* Ignore REX */
178 if (!(REG_CREG & ~regflags))
179 return nasm_rd_creg[regval];
180 if (!(REG_DREG & ~regflags))
181 return nasm_rd_dreg[regval];
182 if (!(REG_TREG & ~regflags)) {
184 return 0; /* TR registers are ill-defined with rex */
185 return nasm_rd_treg[regval];
187 if (!(FPUREG & ~regflags))
188 return nasm_rd_fpureg[regval & 7]; /* Ignore REX */
189 if (!(MMXREG & ~regflags))
190 return nasm_rd_mmxreg[regval & 7]; /* Ignore REX */
191 if (!(XMMREG & ~regflags))
192 return nasm_rd_xmmreg[regval];
193 if (!(YMMREG & ~regflags))
194 return nasm_rd_ymmreg[regval];
200 * Process an effective address (ModRM) specification.
202 static uint8_t *do_ea(uint8_t *data, int modrm, int asize,
203 int segsize, enum ea_type type,
204 operand *op, insn *ins)
206 int mod, rm, scale, index, base;
210 mod = (modrm >> 6) & 03;
213 if (mod != 3 && asize != 16 && rm == 4)
218 if (mod == 3) { /* pure register version */
219 op->basereg = rm+(rex & REX_B ? 8 : 0);
220 op->segment |= SEG_RMREG;
229 * <mod> specifies the displacement size (none, byte or
230 * word), and <rm> specifies the register combination.
231 * Exception: mod=0,rm=6 does not specify [BP] as one might
232 * expect, but instead specifies [disp16].
235 if (type != EA_SCALAR)
238 op->indexreg = op->basereg = -1;
239 op->scale = 1; /* always, in 16 bits */
270 if (rm == 6 && mod == 0) { /* special case */
274 mod = 2; /* fake disp16 */
278 op->segment |= SEG_NODISP;
281 op->segment |= SEG_DISP8;
282 op->offset = (int8_t)*data++;
285 op->segment |= SEG_DISP16;
286 op->offset = *data++;
287 op->offset |= ((unsigned)*data++) << 8;
293 * Once again, <mod> specifies displacement size (this time
294 * none, byte or *dword*), while <rm> specifies the base
295 * register. Again, [EBP] is missing, replaced by a pure
296 * disp32 (this time that's mod=0,rm=*5*) in 32-bit mode,
297 * and RIP-relative addressing in 64-bit mode.
300 * indicates not a single base register, but instead the
301 * presence of a SIB byte...
303 int a64 = asize == 64;
308 op->basereg = nasm_rd_reg64[rm | ((rex & REX_B) ? 8 : 0)];
310 op->basereg = nasm_rd_reg32[rm | ((rex & REX_B) ? 8 : 0)];
312 if (rm == 5 && mod == 0) {
314 op->eaflags |= EAF_REL;
315 op->segment |= SEG_RELATIVE;
316 mod = 2; /* fake disp32 */
320 op->disp_size = asize;
323 mod = 2; /* fake disp32 */
327 if (rm == 4) { /* process SIB */
328 scale = (sib >> 6) & 03;
329 index = (sib >> 3) & 07;
332 op->scale = 1 << scale;
334 if (type == EA_XMMVSIB)
335 op->indexreg = nasm_rd_xmmreg[index | ((rex & REX_X) ? 8 : 0)];
336 else if (type == EA_YMMVSIB)
337 op->indexreg = nasm_rd_ymmreg[index | ((rex & REX_X) ? 8 : 0)];
338 else if (index == 4 && !(rex & REX_X))
339 op->indexreg = -1; /* ESP/RSP cannot be an index */
341 op->indexreg = nasm_rd_reg64[index | ((rex & REX_X) ? 8 : 0)];
343 op->indexreg = nasm_rd_reg32[index | ((rex & REX_X) ? 8 : 0)];
345 if (base == 5 && mod == 0) {
347 mod = 2; /* Fake disp32 */
349 op->basereg = nasm_rd_reg64[base | ((rex & REX_B) ? 8 : 0)];
351 op->basereg = nasm_rd_reg32[base | ((rex & REX_B) ? 8 : 0)];
355 } else if (type != EA_SCALAR) {
356 /* Can't have VSIB without SIB */
362 op->segment |= SEG_NODISP;
365 op->segment |= SEG_DISP8;
366 op->offset = gets8(data);
370 op->segment |= SEG_DISP32;
371 op->offset = gets32(data);
380 * Determine whether the instruction template in t corresponds to the data
381 * stream in data. Return the number of bytes matched if so.
383 #define case4(x) case (x): case (x)+1: case (x)+2: case (x)+3
385 static int matches(const struct itemplate *t, uint8_t *data,
386 const struct prefix_info *prefix, int segsize, insn *ins)
388 uint8_t *r = (uint8_t *)(t->code);
389 uint8_t *origdata = data;
390 bool a_used = false, o_used = false;
391 enum prefixes drep = 0;
392 enum prefixes dwait = 0;
393 uint8_t lock = prefix->lock;
394 int osize = prefix->osize;
395 int asize = prefix->asize;
398 struct operand *opx, *opy;
401 int regmask = (segsize == 64) ? 15 : 7;
402 enum ea_type eat = EA_SCALAR;
404 for (i = 0; i < MAX_OPERANDS; i++) {
405 ins->oprs[i].segment = ins->oprs[i].disp_size =
406 (segsize == 64 ? SEG_64BIT : segsize == 32 ? SEG_32BIT : 0);
409 ins->rex = prefix->rex;
410 memset(ins->prefixes, 0, sizeof ins->prefixes);
412 if (t->flags & (segsize == 64 ? IF_NOLONG : IF_LONG))
415 if (prefix->rep == 0xF2)
417 else if (prefix->rep == 0xF3)
420 dwait = prefix->wait ? P_WAIT : 0;
422 while ((c = *r++) != 0) {
423 op1 = (c & 3) + ((opex & 1) << 2);
424 op2 = ((c >> 3) & 3) + ((opex & 2) << 1);
425 opx = &ins->oprs[op1];
426 opy = &ins->oprs[op2];
447 int t = *r++, d = *data++;
448 if (d < t || d > t + 7)
451 opx->basereg = (d-t)+
452 (ins->rex & REX_B ? 8 : 0);
453 opx->segment |= SEG_RMREG;
459 opx->offset = (int8_t)*data++;
460 opx->segment |= SEG_SIGNED;
464 opx->offset = *data++;
468 opx->offset = *data++;
472 opx->offset = getu16(data);
478 opx->offset = getu32(data);
481 opx->offset = getu16(data);
484 if (segsize != asize)
485 opx->disp_size = asize;
489 opx->offset = getu32(data);
494 opx->offset = gets32(data);
501 opx->offset = getu16(data);
507 opx->offset = getu32(data);
513 opx->offset = getu64(data);
521 opx->offset = gets8(data++);
522 opx->segment |= SEG_RELATIVE;
526 opx->offset = getu64(data);
531 opx->offset = gets16(data);
533 opx->segment |= SEG_RELATIVE;
534 opx->segment &= ~SEG_32BIT;
537 case4(064): /* rel */
538 opx->segment |= SEG_RELATIVE;
539 /* In long mode rel is always 32 bits, sign extended. */
540 if (segsize == 64 || osize == 32) {
541 opx->offset = gets32(data);
544 opx->segment |= SEG_32BIT;
545 opx->type = (opx->type & ~SIZE_MASK)
546 | (segsize == 64 ? BITS64 : BITS32);
548 opx->offset = gets16(data);
550 opx->segment &= ~SEG_32BIT;
551 opx->type = (opx->type & ~SIZE_MASK) | BITS16;
556 opx->offset = gets32(data);
558 opx->segment |= SEG_32BIT | SEG_RELATIVE;
567 opx->segment |= SEG_RMREG;
568 data = do_ea(data, modrm, asize, segsize, eat, opy, ins);
571 opx->basereg = ((modrm >> 3) & 7) + (ins->rex & REX_R ? 8 : 0);
577 uint8_t ximm = *data++;
579 ins->oprs[c >> 3].basereg = (ximm >> 4) & regmask;
580 ins->oprs[c >> 3].segment |= SEG_RMREG;
581 ins->oprs[c & 7].offset = ximm & 15;
587 uint8_t ximm = *data++;
593 ins->oprs[c >> 4].basereg = (ximm >> 4) & regmask;
594 ins->oprs[c >> 4].segment |= SEG_RMREG;
600 uint8_t ximm = *data++;
602 opx->basereg = (ximm >> 4) & regmask;
603 opx->segment |= SEG_RMREG;
617 if (((modrm >> 3) & 07) != (c & 07))
618 return false; /* spare field doesn't match up */
619 data = do_ea(data, modrm, asize, segsize, eat, opy, ins);
632 if ((prefix->rex & (REX_V|REX_P)) != REX_V)
635 if ((vexm & 0x1f) != prefix->vex_m)
638 switch (vexwlp & 060) {
640 if (prefix->rex & REX_W)
644 if (!(prefix->rex & REX_W))
648 case 040: /* VEX.W is a don't care */
655 /* The 010 bit of vexwlp is set if VEX.L is ignored */
656 if ((vexwlp ^ prefix->vex_lp) & ((vexwlp & 010) ? 03 : 07))
660 if (prefix->vex_v != 0)
663 opx->segment |= SEG_RMREG;
664 opx->basereg = prefix->vex_v;
671 if (prefix->rep == 0xF3)
676 if (prefix->rep == 0xF2)
678 else if (prefix->rep == 0xF3)
683 if (prefix->lock == 0xF0) {
684 if (prefix->rep == 0xF2)
686 else if (prefix->rep == 0xF3)
706 if (asize != segsize)
720 if (prefix->rex & REX_B)
725 if (prefix->rex & REX_X)
730 if (prefix->rex & REX_R)
735 if (prefix->rex & REX_W)
754 if (osize != (segsize == 16) ? 16 : 32)
761 ins->rex |= REX_W; /* 64-bit only instruction */
778 int t = *r++, d = *data++;
779 if (d < t || d > t + 15)
782 ins->condition = d - t;
787 if (prefix->rep == 0xF3)
797 if (prefix->rep != 0xF2)
803 if (prefix->rep != 0xF3)
828 if (prefix->wait != 0x9B)
834 ins->oprs[0].basereg = (*data++ >> 3) & 7;
838 if (prefix->osp || prefix->rep)
843 if (!prefix->osp || prefix->rep)
849 if (prefix->osp || prefix->rep != 0xf2)
855 if (prefix->osp || prefix->rep != 0xf3)
895 return false; /* Unknown code */
899 if (!vex_ok && (ins->rex & REX_V))
902 /* REX cannot be combined with VEX */
903 if ((ins->rex & REX_V) && (prefix->rex & REX_P))
907 * Check for unused rep or a/o prefixes.
909 for (i = 0; i < t->operands; i++) {
910 if (ins->oprs[i].segment != SEG_RMREG)
915 if (ins->prefixes[PPS_LOCK])
917 ins->prefixes[PPS_LOCK] = P_LOCK;
920 if (ins->prefixes[PPS_REP])
922 ins->prefixes[PPS_REP] = drep;
924 ins->prefixes[PPS_WAIT] = dwait;
926 if (osize != ((segsize == 16) ? 16 : 32)) {
927 enum prefixes pfx = 0;
941 if (ins->prefixes[PPS_OSIZE])
943 ins->prefixes[PPS_OSIZE] = pfx;
946 if (!a_used && asize != segsize) {
947 if (ins->prefixes[PPS_ASIZE])
949 ins->prefixes[PPS_ASIZE] = asize == 16 ? P_A16 : P_A32;
952 /* Fix: check for redundant REX prefixes */
954 return data - origdata;
957 /* Condition names for disassembly, sorted by x86 code */
958 static const char * const condition_name[16] = {
959 "o", "no", "c", "nc", "z", "nz", "na", "a",
960 "s", "ns", "pe", "po", "l", "nl", "ng", "g"
963 int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize,
964 int32_t offset, int autosync, uint32_t prefer)
966 const struct itemplate * const *p, * const *best_p;
967 const struct disasm_index *ix;
969 int length, best_length = 0;
971 int i, slen, colon, n;
975 uint32_t goodness, best;
977 struct prefix_info prefix;
980 memset(&ins, 0, sizeof ins);
985 memset(&prefix, 0, sizeof prefix);
986 prefix.asize = segsize;
987 prefix.osize = (segsize == 64) ? 32 : segsize;
994 while (!end_prefix) {
998 prefix.rep = *data++;
1002 prefix.wait = *data++;
1006 prefix.lock = *data++;
1010 segover = "cs", prefix.seg = *data++;
1013 segover = "ss", prefix.seg = *data++;
1016 segover = "ds", prefix.seg = *data++;
1019 segover = "es", prefix.seg = *data++;
1022 segover = "fs", prefix.seg = *data++;
1025 segover = "gs", prefix.seg = *data++;
1029 prefix.osize = (segsize == 16) ? 32 : 16;
1030 prefix.osp = *data++;
1033 prefix.asize = (segsize == 32) ? 16 : 32;
1034 prefix.asp = *data++;
1039 if (segsize == 64 || (data[1] & 0xc0) == 0xc0) {
1040 prefix.vex[0] = *data++;
1041 prefix.vex[1] = *data++;
1044 prefix.vex_c = RV_VEX;
1046 if (prefix.vex[0] == 0xc4) {
1047 prefix.vex[2] = *data++;
1048 prefix.rex |= (~prefix.vex[1] >> 5) & 7; /* REX_RXB */
1049 prefix.rex |= (prefix.vex[2] >> (7-3)) & REX_W;
1050 prefix.vex_m = prefix.vex[1] & 0x1f;
1051 prefix.vex_v = (~prefix.vex[2] >> 3) & 15;
1052 prefix.vex_lp = prefix.vex[2] & 7;
1054 prefix.rex |= (~prefix.vex[1] >> (7-2)) & REX_R;
1056 prefix.vex_v = (~prefix.vex[1] >> 3) & 15;
1057 prefix.vex_lp = prefix.vex[1] & 7;
1060 ix = itable_vex[RV_VEX][prefix.vex_m][prefix.vex_lp & 3];
1066 if ((data[1] & 030) != 0 &&
1067 (segsize == 64 || (data[1] & 0xc0) == 0xc0)) {
1068 prefix.vex[0] = *data++;
1069 prefix.vex[1] = *data++;
1070 prefix.vex[2] = *data++;
1073 prefix.vex_c = RV_XOP;
1075 prefix.rex |= (~prefix.vex[1] >> 5) & 7; /* REX_RXB */
1076 prefix.rex |= (prefix.vex[2] >> (7-3)) & REX_W;
1077 prefix.vex_m = prefix.vex[1] & 0x1f;
1078 prefix.vex_v = (~prefix.vex[2] >> 3) & 15;
1079 prefix.vex_lp = prefix.vex[2] & 7;
1081 ix = itable_vex[RV_XOP][prefix.vex_m][prefix.vex_lp & 3];
1102 if (segsize == 64) {
1103 prefix.rex = *data++;
1104 if (prefix.rex & REX_W)
1116 best = -1; /* Worst possible */
1118 best_pref = INT_MAX;
1121 return 0; /* No instruction table at all... */
1125 while (ix->n == -1) {
1126 ix = (const struct disasm_index *)ix->p + *dp++;
1129 p = (const struct itemplate * const *)ix->p;
1130 for (n = ix->n; n; n--, p++) {
1131 if ((length = matches(*p, data, &prefix, segsize, &tmp_ins))) {
1134 * Final check to make sure the types of r/m match up.
1135 * XXX: Need to make sure this is actually correct.
1137 for (i = 0; i < (*p)->operands; i++) {
1138 if (!((*p)->opd[i] & SAME_AS) &&
1140 /* If it's a mem-only EA but we have a
1142 ((tmp_ins.oprs[i].segment & SEG_RMREG) &&
1143 is_class(MEMORY, (*p)->opd[i])) ||
1144 /* If it's a reg-only EA but we have a memory
1146 (!(tmp_ins.oprs[i].segment & SEG_RMREG) &&
1147 !(REG_EA & ~(*p)->opd[i]) &&
1148 !((*p)->opd[i] & REG_SMASK)) ||
1149 /* Register type mismatch (eg FS vs REG_DESS):
1151 ((((*p)->opd[i] & (REGISTER | FPUREG)) ||
1152 (tmp_ins.oprs[i].segment & SEG_RMREG)) &&
1153 !whichreg((*p)->opd[i],
1154 tmp_ins.oprs[i].basereg, tmp_ins.rex))
1162 * Note: we always prefer instructions which incorporate
1163 * prefixes in the instructions themselves. This is to allow
1164 * e.g. PAUSE to be preferred to REP NOP, and deal with
1165 * MMX/SSE instructions where prefixes are used to select
1166 * between MMX and SSE register sets or outright opcode
1171 goodness = ((*p)->flags & IF_PFMASK) ^ prefer;
1173 for (i = 0; i < MAXPREFIX; i++)
1174 if (tmp_ins.prefixes[i])
1176 if (nprefix < best_pref ||
1177 (nprefix == best_pref && goodness < best)) {
1178 /* This is the best one found so far */
1181 best_pref = nprefix;
1182 best_length = length;
1190 return 0; /* no instruction was matched */
1192 /* Pick the best match */
1194 length = best_length;
1198 /* TODO: snprintf returns the value that the string would have if
1199 * the buffer were long enough, and not the actual length of
1200 * the returned string, so each instance of using the return
1201 * value of snprintf should actually be checked to assure that
1202 * the return value is "sane." Maybe a macro wrapper could
1203 * be used for that purpose.
1205 for (i = 0; i < MAXPREFIX; i++) {
1206 const char *prefix = prefix_name(ins.prefixes[i]);
1208 slen += snprintf(output+slen, outbufsize-slen, "%s ", prefix);
1212 if (i >= FIRST_COND_OPCODE)
1213 slen += snprintf(output + slen, outbufsize - slen, "%s%s",
1214 nasm_insn_names[i], condition_name[ins.condition]);
1216 slen += snprintf(output + slen, outbufsize - slen, "%s",
1217 nasm_insn_names[i]);
1220 length += data - origdata; /* fix up for prefixes */
1221 for (i = 0; i < (*p)->operands; i++) {
1222 opflags_t t = (*p)->opd[i];
1223 const operand *o = &ins.oprs[i];
1227 o = &ins.oprs[t & ~SAME_AS];
1228 t = (*p)->opd[t & ~SAME_AS];
1231 output[slen++] = (colon ? ':' : i == 0 ? ' ' : ',');
1234 if (o->segment & SEG_RELATIVE) {
1235 offs += offset + length;
1237 * sort out wraparound
1239 if (!(o->segment & (SEG_32BIT|SEG_64BIT)))
1241 else if (segsize != 64)
1245 * add sync marker, if autosync is on
1256 if ((t & (REGISTER | FPUREG)) ||
1257 (o->segment & SEG_RMREG)) {
1259 reg = whichreg(t, o->basereg, ins.rex);
1261 slen += snprintf(output + slen, outbufsize - slen, "to ");
1262 slen += snprintf(output + slen, outbufsize - slen, "%s",
1263 nasm_reg_names[reg-EXPR_REG_START]);
1264 } else if (!(UNITY & ~t)) {
1265 output[slen++] = '1';
1266 } else if (t & IMMEDIATE) {
1269 snprintf(output + slen, outbufsize - slen, "byte ");
1270 if (o->segment & SEG_SIGNED) {
1273 output[slen++] = '-';
1275 output[slen++] = '+';
1277 } else if (t & BITS16) {
1279 snprintf(output + slen, outbufsize - slen, "word ");
1280 } else if (t & BITS32) {
1282 snprintf(output + slen, outbufsize - slen, "dword ");
1283 } else if (t & BITS64) {
1285 snprintf(output + slen, outbufsize - slen, "qword ");
1286 } else if (t & NEAR) {
1288 snprintf(output + slen, outbufsize - slen, "near ");
1289 } else if (t & SHORT) {
1291 snprintf(output + slen, outbufsize - slen, "short ");
1294 snprintf(output + slen, outbufsize - slen, "0x%"PRIx64"",
1296 } else if (!(MEM_OFFS & ~t)) {
1298 snprintf(output + slen, outbufsize - slen,
1299 "[%s%s%s0x%"PRIx64"]",
1300 (segover ? segover : ""),
1301 (segover ? ":" : ""),
1302 (o->disp_size == 64 ? "qword " :
1303 o->disp_size == 32 ? "dword " :
1304 o->disp_size == 16 ? "word " : ""), offs);
1306 } else if (is_class(REGMEM, t)) {
1307 int started = false;
1310 snprintf(output + slen, outbufsize - slen, "byte ");
1313 snprintf(output + slen, outbufsize - slen, "word ");
1316 snprintf(output + slen, outbufsize - slen, "dword ");
1319 snprintf(output + slen, outbufsize - slen, "qword ");
1322 snprintf(output + slen, outbufsize - slen, "tword ");
1325 snprintf(output + slen, outbufsize - slen, "oword ");
1328 snprintf(output + slen, outbufsize - slen, "yword ");
1330 slen += snprintf(output + slen, outbufsize - slen, "far ");
1333 snprintf(output + slen, outbufsize - slen, "near ");
1334 output[slen++] = '[';
1336 slen += snprintf(output + slen, outbufsize - slen, "%s",
1337 (o->disp_size == 64 ? "qword " :
1338 o->disp_size == 32 ? "dword " :
1339 o->disp_size == 16 ? "word " :
1341 if (o->eaflags & EAF_REL)
1342 slen += snprintf(output + slen, outbufsize - slen, "rel ");
1345 snprintf(output + slen, outbufsize - slen, "%s:",
1349 if (o->basereg != -1) {
1350 slen += snprintf(output + slen, outbufsize - slen, "%s",
1351 nasm_reg_names[(o->basereg-EXPR_REG_START)]);
1354 if (o->indexreg != -1) {
1356 output[slen++] = '+';
1357 slen += snprintf(output + slen, outbufsize - slen, "%s",
1358 nasm_reg_names[(o->indexreg-EXPR_REG_START)]);
1361 snprintf(output + slen, outbufsize - slen, "*%d",
1367 if (o->segment & SEG_DISP8) {
1369 uint8_t offset = offs;
1370 if ((int8_t)offset < 0) {
1377 snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx8"",
1379 } else if (o->segment & SEG_DISP16) {
1381 uint16_t offset = offs;
1382 if ((int16_t)offset < 0 && started) {
1386 prefix = started ? "+" : "";
1389 snprintf(output + slen, outbufsize - slen,
1390 "%s0x%"PRIx16"", prefix, offset);
1391 } else if (o->segment & SEG_DISP32) {
1392 if (prefix.asize == 64) {
1394 uint64_t offset = (int64_t)(int32_t)offs;
1395 if ((int32_t)offs < 0 && started) {
1399 prefix = started ? "+" : "";
1402 snprintf(output + slen, outbufsize - slen,
1403 "%s0x%"PRIx64"", prefix, offset);
1406 uint32_t offset = offs;
1407 if ((int32_t) offset < 0 && started) {
1411 prefix = started ? "+" : "";
1414 snprintf(output + slen, outbufsize - slen,
1415 "%s0x%"PRIx32"", prefix, offset);
1418 output[slen++] = ']';
1421 snprintf(output + slen, outbufsize - slen, "<operand%d>",
1425 output[slen] = '\0';
1426 if (segover) { /* unused segment override */
1428 int count = slen + 1;
1430 p[count + 3] = p[count];
1431 strncpy(output, segover, 2);
1438 * This is called when we don't have a complete instruction. If it
1439 * is a standalone *single-byte* prefix show it as such, otherwise
1440 * print it as a literal.
1442 int32_t eatbyte(uint8_t *data, char *output, int outbufsize, int segsize)
1444 uint8_t byte = *data;
1445 const char *str = NULL;
1479 str = (segsize == 16) ? "o32" : "o16";
1482 str = (segsize == 32) ? "a16" : "a32";
1500 if (segsize == 64) {
1501 snprintf(output, outbufsize, "rex%s%s%s%s%s",
1502 (byte == REX_P) ? "" : ".",
1503 (byte & REX_W) ? "w" : "",
1504 (byte & REX_R) ? "r" : "",
1505 (byte & REX_X) ? "x" : "",
1506 (byte & REX_B) ? "b" : "");
1509 /* else fall through */
1511 snprintf(output, outbufsize, "db 0x%02x", byte);
1516 snprintf(output, outbufsize, "%s", str);