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
)
117 static const struct {
120 } specific_registers
[] = {
144 if (!(regflags
& (REGISTER
|REGMEM
)))
145 return 0; /* Registers not permissible?! */
147 regflags
|= REGISTER
;
149 for (i
= 0; i
< ARRAY_SIZE(specific_registers
); i
++)
150 if (!(specific_registers
[i
].flags
& ~regflags
))
151 return specific_registers
[i
].reg
;
153 /* All the entries below look up regval in an 16-entry array */
154 if (regval
< 0 || regval
> 15)
157 if (!(REG8
& ~regflags
)) {
158 if (rex
& (REX_P
|REX_NH
))
159 return nasm_rd_reg8_rex
[regval
];
161 return nasm_rd_reg8
[regval
];
163 if (!(REG16
& ~regflags
))
164 return nasm_rd_reg16
[regval
];
165 if (!(REG32
& ~regflags
))
166 return nasm_rd_reg32
[regval
];
167 if (!(REG64
& ~regflags
))
168 return nasm_rd_reg64
[regval
];
169 if (!(REG_SREG
& ~regflags
))
170 return nasm_rd_sreg
[regval
& 7]; /* Ignore REX */
171 if (!(REG_CREG
& ~regflags
))
172 return nasm_rd_creg
[regval
];
173 if (!(REG_DREG
& ~regflags
))
174 return nasm_rd_dreg
[regval
];
175 if (!(REG_TREG
& ~regflags
)) {
177 return 0; /* TR registers are ill-defined with rex */
178 return nasm_rd_treg
[regval
];
180 if (!(FPUREG
& ~regflags
))
181 return nasm_rd_fpureg
[regval
& 7]; /* Ignore REX */
182 if (!(MMXREG
& ~regflags
))
183 return nasm_rd_mmxreg
[regval
& 7]; /* Ignore REX */
184 if (!(XMMREG
& ~regflags
))
185 return nasm_rd_xmmreg
[regval
];
186 if (!(YMMREG
& ~regflags
))
187 return nasm_rd_ymmreg
[regval
];
193 * Process an effective address (ModRM) specification.
195 static uint8_t *do_ea(uint8_t *data
, int modrm
, int asize
,
196 int segsize
, enum ea_type type
,
197 operand
*op
, insn
*ins
)
199 int mod
, rm
, scale
, index
, base
;
203 mod
= (modrm
>> 6) & 03;
206 if (mod
!= 3 && asize
!= 16 && rm
== 4)
211 if (mod
== 3) { /* pure register version */
212 op
->basereg
= rm
+(rex
& REX_B
? 8 : 0);
213 op
->segment
|= SEG_RMREG
;
222 * <mod> specifies the displacement size (none, byte or
223 * word), and <rm> specifies the register combination.
224 * Exception: mod=0,rm=6 does not specify [BP] as one might
225 * expect, but instead specifies [disp16].
228 if (type
!= EA_SCALAR
)
231 op
->indexreg
= op
->basereg
= -1;
232 op
->scale
= 1; /* always, in 16 bits */
263 if (rm
== 6 && mod
== 0) { /* special case */
267 mod
= 2; /* fake disp16 */
271 op
->segment
|= SEG_NODISP
;
274 op
->segment
|= SEG_DISP8
;
275 op
->offset
= (int8_t)*data
++;
278 op
->segment
|= SEG_DISP16
;
279 op
->offset
= *data
++;
280 op
->offset
|= ((unsigned)*data
++) << 8;
286 * Once again, <mod> specifies displacement size (this time
287 * none, byte or *dword*), while <rm> specifies the base
288 * register. Again, [EBP] is missing, replaced by a pure
289 * disp32 (this time that's mod=0,rm=*5*) in 32-bit mode,
290 * and RIP-relative addressing in 64-bit mode.
293 * indicates not a single base register, but instead the
294 * presence of a SIB byte...
296 int a64
= asize
== 64;
301 op
->basereg
= nasm_rd_reg64
[rm
| ((rex
& REX_B
) ? 8 : 0)];
303 op
->basereg
= nasm_rd_reg32
[rm
| ((rex
& REX_B
) ? 8 : 0)];
305 if (rm
== 5 && mod
== 0) {
307 op
->eaflags
|= EAF_REL
;
308 op
->segment
|= SEG_RELATIVE
;
309 mod
= 2; /* fake disp32 */
313 op
->disp_size
= asize
;
316 mod
= 2; /* fake disp32 */
320 if (rm
== 4) { /* process SIB */
321 scale
= (sib
>> 6) & 03;
322 index
= (sib
>> 3) & 07;
325 op
->scale
= 1 << scale
;
327 if (type
== EA_XMMVSIB
)
328 op
->indexreg
= nasm_rd_xmmreg
[index
| ((rex
& REX_X
) ? 8 : 0)];
329 else if (type
== EA_YMMVSIB
)
330 op
->indexreg
= nasm_rd_ymmreg
[index
| ((rex
& REX_X
) ? 8 : 0)];
331 else if (type
== EA_ZMMVSIB
)
332 op
->indexreg
= nasm_rd_zmmreg
[index
| ((rex
& REX_X
) ? 8 : 0)];
333 else if (index
== 4 && !(rex
& REX_X
))
334 op
->indexreg
= -1; /* ESP/RSP cannot be an index */
336 op
->indexreg
= nasm_rd_reg64
[index
| ((rex
& REX_X
) ? 8 : 0)];
338 op
->indexreg
= nasm_rd_reg32
[index
| ((rex
& REX_X
) ? 8 : 0)];
340 if (base
== 5 && mod
== 0) {
342 mod
= 2; /* Fake disp32 */
344 op
->basereg
= nasm_rd_reg64
[base
| ((rex
& REX_B
) ? 8 : 0)];
346 op
->basereg
= nasm_rd_reg32
[base
| ((rex
& REX_B
) ? 8 : 0)];
350 } else if (type
!= EA_SCALAR
) {
351 /* Can't have VSIB without SIB */
357 op
->segment
|= SEG_NODISP
;
360 op
->segment
|= SEG_DISP8
;
361 op
->offset
= gets8(data
);
365 op
->segment
|= SEG_DISP32
;
366 op
->offset
= gets32(data
);
375 * Determine whether the instruction template in t corresponds to the data
376 * stream in data. Return the number of bytes matched if so.
378 #define case4(x) case (x): case (x)+1: case (x)+2: case (x)+3
380 static int matches(const struct itemplate
*t
, uint8_t *data
,
381 const struct prefix_info
*prefix
, int segsize
, insn
*ins
)
383 uint8_t *r
= (uint8_t *)(t
->code
);
384 uint8_t *origdata
= data
;
385 bool a_used
= false, o_used
= false;
386 enum prefixes drep
= 0;
387 enum prefixes dwait
= 0;
388 uint8_t lock
= prefix
->lock
;
389 int osize
= prefix
->osize
;
390 int asize
= prefix
->asize
;
393 struct operand
*opx
, *opy
;
396 int regmask
= (segsize
== 64) ? 15 : 7;
397 enum ea_type eat
= EA_SCALAR
;
399 for (i
= 0; i
< MAX_OPERANDS
; i
++) {
400 ins
->oprs
[i
].segment
= ins
->oprs
[i
].disp_size
=
401 (segsize
== 64 ? SEG_64BIT
: segsize
== 32 ? SEG_32BIT
: 0);
404 ins
->rex
= prefix
->rex
;
405 memset(ins
->prefixes
, 0, sizeof ins
->prefixes
);
407 if (t
->flags
& (segsize
== 64 ? IF_NOLONG
: IF_LONG
))
410 if (prefix
->rep
== 0xF2)
412 else if (prefix
->rep
== 0xF3)
415 dwait
= prefix
->wait
? P_WAIT
: 0;
417 while ((c
= *r
++) != 0) {
418 op1
= (c
& 3) + ((opex
& 1) << 2);
419 op2
= ((c
>> 3) & 3) + ((opex
& 2) << 1);
420 opx
= &ins
->oprs
[op1
];
421 opy
= &ins
->oprs
[op2
];
442 int t
= *r
++, d
= *data
++;
443 if (d
< t
|| d
> t
+ 7)
446 opx
->basereg
= (d
-t
)+
447 (ins
->rex
& REX_B
? 8 : 0);
448 opx
->segment
|= SEG_RMREG
;
454 opx
->offset
= (int8_t)*data
++;
455 opx
->segment
|= SEG_SIGNED
;
459 opx
->offset
= *data
++;
463 opx
->offset
= *data
++;
467 opx
->offset
= getu16(data
);
473 opx
->offset
= getu32(data
);
476 opx
->offset
= getu16(data
);
479 if (segsize
!= asize
)
480 opx
->disp_size
= asize
;
484 opx
->offset
= getu32(data
);
489 opx
->offset
= gets32(data
);
496 opx
->offset
= getu16(data
);
502 opx
->offset
= getu32(data
);
508 opx
->offset
= getu64(data
);
516 opx
->offset
= gets8(data
++);
517 opx
->segment
|= SEG_RELATIVE
;
521 opx
->offset
= getu64(data
);
526 opx
->offset
= gets16(data
);
528 opx
->segment
|= SEG_RELATIVE
;
529 opx
->segment
&= ~SEG_32BIT
;
532 case4(064): /* rel */
533 opx
->segment
|= SEG_RELATIVE
;
534 /* In long mode rel is always 32 bits, sign extended. */
535 if (segsize
== 64 || osize
== 32) {
536 opx
->offset
= gets32(data
);
539 opx
->segment
|= SEG_32BIT
;
540 opx
->type
= (opx
->type
& ~SIZE_MASK
)
541 | (segsize
== 64 ? BITS64
: BITS32
);
543 opx
->offset
= gets16(data
);
545 opx
->segment
&= ~SEG_32BIT
;
546 opx
->type
= (opx
->type
& ~SIZE_MASK
) | BITS16
;
551 opx
->offset
= gets32(data
);
553 opx
->segment
|= SEG_32BIT
| SEG_RELATIVE
;
562 opx
->segment
|= SEG_RMREG
;
563 data
= do_ea(data
, modrm
, asize
, segsize
, eat
, opy
, ins
);
566 opx
->basereg
= ((modrm
>> 3) & 7) + (ins
->rex
& REX_R
? 8 : 0);
572 uint8_t ximm
= *data
++;
574 ins
->oprs
[c
>> 3].basereg
= (ximm
>> 4) & regmask
;
575 ins
->oprs
[c
>> 3].segment
|= SEG_RMREG
;
576 ins
->oprs
[c
& 7].offset
= ximm
& 15;
582 uint8_t ximm
= *data
++;
588 ins
->oprs
[c
>> 4].basereg
= (ximm
>> 4) & regmask
;
589 ins
->oprs
[c
>> 4].segment
|= SEG_RMREG
;
595 uint8_t ximm
= *data
++;
597 opx
->basereg
= (ximm
>> 4) & regmask
;
598 opx
->segment
|= SEG_RMREG
;
612 if (((modrm
>> 3) & 07) != (c
& 07))
613 return false; /* spare field doesn't match up */
614 data
= do_ea(data
, modrm
, asize
, segsize
, eat
, opy
, ins
);
627 if ((prefix
->rex
& (REX_V
|REX_P
)) != REX_V
)
630 if ((vexm
& 0x1f) != prefix
->vex_m
)
633 switch (vexwlp
& 060) {
635 if (prefix
->rex
& REX_W
)
639 if (!(prefix
->rex
& REX_W
))
643 case 040: /* VEX.W is a don't care */
650 /* The 010 bit of vexwlp is set if VEX.L is ignored */
651 if ((vexwlp
^ prefix
->vex_lp
) & ((vexwlp
& 010) ? 03 : 07))
655 if (prefix
->vex_v
!= 0)
658 opx
->segment
|= SEG_RMREG
;
659 opx
->basereg
= prefix
->vex_v
;
666 if (prefix
->rep
== 0xF3)
671 if (prefix
->rep
== 0xF2)
673 else if (prefix
->rep
== 0xF3)
678 if (prefix
->lock
== 0xF0) {
679 if (prefix
->rep
== 0xF2)
681 else if (prefix
->rep
== 0xF3)
701 if (asize
!= segsize
)
715 if (prefix
->rex
& REX_B
)
720 if (prefix
->rex
& REX_X
)
725 if (prefix
->rex
& REX_R
)
730 if (prefix
->rex
& REX_W
)
749 if (osize
!= (segsize
== 16) ? 16 : 32)
756 ins
->rex
|= REX_W
; /* 64-bit only instruction */
773 int t
= *r
++, d
= *data
++;
774 if (d
< t
|| d
> t
+ 15)
777 ins
->condition
= d
- t
;
782 if (prefix
->rep
== 0xF3)
792 if (prefix
->rep
!= 0xF2)
798 if (prefix
->rep
!= 0xF3)
823 if (prefix
->wait
!= 0x9B)
829 if (prefix
->osp
|| prefix
->rep
)
834 if (!prefix
->osp
|| prefix
->rep
)
878 return false; /* Unknown code */
882 if (!vex_ok
&& (ins
->rex
& REX_V
))
885 /* REX cannot be combined with VEX */
886 if ((ins
->rex
& REX_V
) && (prefix
->rex
& REX_P
))
890 * Check for unused rep or a/o prefixes.
892 for (i
= 0; i
< t
->operands
; i
++) {
893 if (ins
->oprs
[i
].segment
!= SEG_RMREG
)
898 if (ins
->prefixes
[PPS_LOCK
])
900 ins
->prefixes
[PPS_LOCK
] = P_LOCK
;
903 if (ins
->prefixes
[PPS_REP
])
905 ins
->prefixes
[PPS_REP
] = drep
;
907 ins
->prefixes
[PPS_WAIT
] = dwait
;
909 if (osize
!= ((segsize
== 16) ? 16 : 32)) {
910 enum prefixes pfx
= 0;
924 if (ins
->prefixes
[PPS_OSIZE
])
926 ins
->prefixes
[PPS_OSIZE
] = pfx
;
929 if (!a_used
&& asize
!= segsize
) {
930 if (ins
->prefixes
[PPS_ASIZE
])
932 ins
->prefixes
[PPS_ASIZE
] = asize
== 16 ? P_A16
: P_A32
;
935 /* Fix: check for redundant REX prefixes */
937 return data
- origdata
;
940 /* Condition names for disassembly, sorted by x86 code */
941 static const char * const condition_name
[16] = {
942 "o", "no", "c", "nc", "z", "nz", "na", "a",
943 "s", "ns", "pe", "po", "l", "nl", "ng", "g"
946 int32_t disasm(uint8_t *data
, char *output
, int outbufsize
, int segsize
,
947 int32_t offset
, int autosync
, iflags_t prefer
)
949 const struct itemplate
* const *p
, * const *best_p
;
950 const struct disasm_index
*ix
;
952 int length
, best_length
= 0;
954 int i
, slen
, colon
, n
;
958 iflags_t goodness
, best
, flags
;
960 struct prefix_info prefix
;
963 memset(&ins
, 0, sizeof ins
);
968 memset(&prefix
, 0, sizeof prefix
);
969 prefix
.asize
= segsize
;
970 prefix
.osize
= (segsize
== 64) ? 32 : segsize
;
977 while (!end_prefix
) {
981 prefix
.rep
= *data
++;
985 prefix
.wait
= *data
++;
989 prefix
.lock
= *data
++;
993 segover
= "cs", prefix
.seg
= *data
++;
996 segover
= "ss", prefix
.seg
= *data
++;
999 segover
= "ds", prefix
.seg
= *data
++;
1002 segover
= "es", prefix
.seg
= *data
++;
1005 segover
= "fs", prefix
.seg
= *data
++;
1008 segover
= "gs", prefix
.seg
= *data
++;
1012 prefix
.osize
= (segsize
== 16) ? 32 : 16;
1013 prefix
.osp
= *data
++;
1016 prefix
.asize
= (segsize
== 32) ? 16 : 32;
1017 prefix
.asp
= *data
++;
1022 if (segsize
== 64 || (data
[1] & 0xc0) == 0xc0) {
1023 prefix
.vex
[0] = *data
++;
1024 prefix
.vex
[1] = *data
++;
1027 prefix
.vex_c
= RV_VEX
;
1029 if (prefix
.vex
[0] == 0xc4) {
1030 prefix
.vex
[2] = *data
++;
1031 prefix
.rex
|= (~prefix
.vex
[1] >> 5) & 7; /* REX_RXB */
1032 prefix
.rex
|= (prefix
.vex
[2] >> (7-3)) & REX_W
;
1033 prefix
.vex_m
= prefix
.vex
[1] & 0x1f;
1034 prefix
.vex_v
= (~prefix
.vex
[2] >> 3) & 15;
1035 prefix
.vex_lp
= prefix
.vex
[2] & 7;
1037 prefix
.rex
|= (~prefix
.vex
[1] >> (7-2)) & REX_R
;
1039 prefix
.vex_v
= (~prefix
.vex
[1] >> 3) & 15;
1040 prefix
.vex_lp
= prefix
.vex
[1] & 7;
1043 ix
= itable_vex
[RV_VEX
][prefix
.vex_m
][prefix
.vex_lp
& 3];
1049 if ((data
[1] & 030) != 0 &&
1050 (segsize
== 64 || (data
[1] & 0xc0) == 0xc0)) {
1051 prefix
.vex
[0] = *data
++;
1052 prefix
.vex
[1] = *data
++;
1053 prefix
.vex
[2] = *data
++;
1056 prefix
.vex_c
= RV_XOP
;
1058 prefix
.rex
|= (~prefix
.vex
[1] >> 5) & 7; /* REX_RXB */
1059 prefix
.rex
|= (prefix
.vex
[2] >> (7-3)) & REX_W
;
1060 prefix
.vex_m
= prefix
.vex
[1] & 0x1f;
1061 prefix
.vex_v
= (~prefix
.vex
[2] >> 3) & 15;
1062 prefix
.vex_lp
= prefix
.vex
[2] & 7;
1064 ix
= itable_vex
[RV_XOP
][prefix
.vex_m
][prefix
.vex_lp
& 3];
1085 if (segsize
== 64) {
1086 prefix
.rex
= *data
++;
1087 if (prefix
.rex
& REX_W
)
1099 best
= -1; /* Worst possible */
1101 best_pref
= INT_MAX
;
1104 return 0; /* No instruction table at all... */
1108 while (ix
->n
== -1) {
1109 ix
= (const struct disasm_index
*)ix
->p
+ *dp
++;
1112 p
= (const struct itemplate
* const *)ix
->p
;
1113 for (n
= ix
->n
; n
; n
--, p
++) {
1114 if ((length
= matches(*p
, data
, &prefix
, segsize
, &tmp_ins
))) {
1117 * Final check to make sure the types of r/m match up.
1118 * XXX: Need to make sure this is actually correct.
1120 for (i
= 0; i
< (*p
)->operands
; i
++) {
1122 /* If it's a mem-only EA but we have a
1124 ((tmp_ins
.oprs
[i
].segment
& SEG_RMREG
) &&
1125 is_class(MEMORY
, (*p
)->opd
[i
])) ||
1126 /* If it's a reg-only EA but we have a memory
1128 (!(tmp_ins
.oprs
[i
].segment
& SEG_RMREG
) &&
1129 !(REG_EA
& ~(*p
)->opd
[i
]) &&
1130 !((*p
)->opd
[i
] & REG_SMASK
)) ||
1131 /* Register type mismatch (eg FS vs REG_DESS):
1133 ((((*p
)->opd
[i
] & (REGISTER
| FPUREG
)) ||
1134 (tmp_ins
.oprs
[i
].segment
& SEG_RMREG
)) &&
1135 !whichreg((*p
)->opd
[i
],
1136 tmp_ins
.oprs
[i
].basereg
, tmp_ins
.rex
))
1144 * Note: we always prefer instructions which incorporate
1145 * prefixes in the instructions themselves. This is to allow
1146 * e.g. PAUSE to be preferred to REP NOP, and deal with
1147 * MMX/SSE instructions where prefixes are used to select
1148 * between MMX and SSE register sets or outright opcode
1153 goodness
= ((*p
)->flags
& IF_PFMASK
) ^ prefer
;
1155 for (i
= 0; i
< MAXPREFIX
; i
++)
1156 if (tmp_ins
.prefixes
[i
])
1158 if (nprefix
< best_pref
||
1159 (nprefix
== best_pref
&& goodness
< best
)) {
1160 /* This is the best one found so far */
1163 best_pref
= nprefix
;
1164 best_length
= length
;
1172 return 0; /* no instruction was matched */
1174 /* Pick the best match */
1176 length
= best_length
;
1177 flags
= (*p
)->flags
;
1181 /* TODO: snprintf returns the value that the string would have if
1182 * the buffer were long enough, and not the actual length of
1183 * the returned string, so each instance of using the return
1184 * value of snprintf should actually be checked to assure that
1185 * the return value is "sane." Maybe a macro wrapper could
1186 * be used for that purpose.
1188 for (i
= 0; i
< MAXPREFIX
; i
++) {
1189 const char *prefix
= prefix_name(ins
.prefixes
[i
]);
1191 slen
+= snprintf(output
+slen
, outbufsize
-slen
, "%s ", prefix
);
1195 if (i
>= FIRST_COND_OPCODE
)
1196 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s%s",
1197 nasm_insn_names
[i
], condition_name
[ins
.condition
]);
1199 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
1200 nasm_insn_names
[i
]);
1203 length
+= data
- origdata
; /* fix up for prefixes */
1204 for (i
= 0; i
< (*p
)->operands
; i
++) {
1205 opflags_t t
= (*p
)->opd
[i
];
1206 const operand
*o
= &ins
.oprs
[i
];
1209 output
[slen
++] = (colon
? ':' : i
== 0 ? ' ' : ',');
1212 if (o
->segment
& SEG_RELATIVE
) {
1213 offs
+= offset
+ length
;
1215 * sort out wraparound
1217 if (!(o
->segment
& (SEG_32BIT
|SEG_64BIT
)))
1219 else if (segsize
!= 64)
1223 * add sync marker, if autosync is on
1234 if ((t
& (REGISTER
| FPUREG
)) ||
1235 (o
->segment
& SEG_RMREG
)) {
1237 reg
= whichreg(t
, o
->basereg
, ins
.rex
);
1239 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "to ");
1240 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
1241 nasm_reg_names
[reg
-EXPR_REG_START
]);
1242 } else if (!(UNITY
& ~t
)) {
1243 output
[slen
++] = '1';
1244 } else if (t
& IMMEDIATE
) {
1247 snprintf(output
+ slen
, outbufsize
- slen
, "byte ");
1248 if (o
->segment
& SEG_SIGNED
) {
1251 output
[slen
++] = '-';
1253 output
[slen
++] = '+';
1255 } else if (t
& BITS16
) {
1257 snprintf(output
+ slen
, outbufsize
- slen
, "word ");
1258 } else if (t
& BITS32
) {
1260 snprintf(output
+ slen
, outbufsize
- slen
, "dword ");
1261 } else if (t
& BITS64
) {
1263 snprintf(output
+ slen
, outbufsize
- slen
, "qword ");
1264 } else if (t
& NEAR
) {
1266 snprintf(output
+ slen
, outbufsize
- slen
, "near ");
1267 } else if (t
& SHORT
) {
1269 snprintf(output
+ slen
, outbufsize
- slen
, "short ");
1272 snprintf(output
+ slen
, outbufsize
- slen
, "0x%"PRIx64
"",
1274 } else if (!(MEM_OFFS
& ~t
)) {
1276 snprintf(output
+ slen
, outbufsize
- slen
,
1277 "[%s%s%s0x%"PRIx64
"]",
1278 (segover
? segover
: ""),
1279 (segover
? ":" : ""),
1280 (o
->disp_size
== 64 ? "qword " :
1281 o
->disp_size
== 32 ? "dword " :
1282 o
->disp_size
== 16 ? "word " : ""), offs
);
1284 } else if (is_class(REGMEM
, t
)) {
1285 int started
= false;
1288 snprintf(output
+ slen
, outbufsize
- slen
, "byte ");
1291 snprintf(output
+ slen
, outbufsize
- slen
, "word ");
1294 snprintf(output
+ slen
, outbufsize
- slen
, "dword ");
1297 snprintf(output
+ slen
, outbufsize
- slen
, "qword ");
1300 snprintf(output
+ slen
, outbufsize
- slen
, "tword ");
1303 snprintf(output
+ slen
, outbufsize
- slen
, "oword ");
1306 snprintf(output
+ slen
, outbufsize
- slen
, "yword ");
1309 snprintf(output
+ slen
, outbufsize
- slen
, "zword ");
1311 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "far ");
1314 snprintf(output
+ slen
, outbufsize
- slen
, "near ");
1315 output
[slen
++] = '[';
1317 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
1318 (o
->disp_size
== 64 ? "qword " :
1319 o
->disp_size
== 32 ? "dword " :
1320 o
->disp_size
== 16 ? "word " :
1322 if (o
->eaflags
& EAF_REL
)
1323 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "rel ");
1326 snprintf(output
+ slen
, outbufsize
- slen
, "%s:",
1330 if (o
->basereg
!= -1) {
1331 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
1332 nasm_reg_names
[(o
->basereg
-EXPR_REG_START
)]);
1335 if (o
->indexreg
!= -1 && !(flags
& IF_MIB
)) {
1337 output
[slen
++] = '+';
1338 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
1339 nasm_reg_names
[(o
->indexreg
-EXPR_REG_START
)]);
1342 snprintf(output
+ slen
, outbufsize
- slen
, "*%d",
1348 if (o
->segment
& SEG_DISP8
) {
1350 uint8_t offset
= offs
;
1351 if ((int8_t)offset
< 0) {
1358 snprintf(output
+ slen
, outbufsize
- slen
, "%s0x%"PRIx8
"",
1360 } else if (o
->segment
& SEG_DISP16
) {
1362 uint16_t offset
= offs
;
1363 if ((int16_t)offset
< 0 && started
) {
1367 prefix
= started
? "+" : "";
1370 snprintf(output
+ slen
, outbufsize
- slen
,
1371 "%s0x%"PRIx16
"", prefix
, offset
);
1372 } else if (o
->segment
& SEG_DISP32
) {
1373 if (prefix
.asize
== 64) {
1375 uint64_t offset
= (int64_t)(int32_t)offs
;
1376 if ((int32_t)offs
< 0 && started
) {
1380 prefix
= started
? "+" : "";
1383 snprintf(output
+ slen
, outbufsize
- slen
,
1384 "%s0x%"PRIx64
"", prefix
, offset
);
1387 uint32_t offset
= offs
;
1388 if ((int32_t) offset
< 0 && started
) {
1392 prefix
= started
? "+" : "";
1395 snprintf(output
+ slen
, outbufsize
- slen
,
1396 "%s0x%"PRIx32
"", prefix
, offset
);
1400 if (o
->indexreg
!= -1 && (flags
& IF_MIB
)) {
1401 output
[slen
++] = ',';
1402 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
1403 nasm_reg_names
[(o
->indexreg
-EXPR_REG_START
)]);
1406 snprintf(output
+ slen
, outbufsize
- slen
, "*%d",
1411 output
[slen
++] = ']';
1414 snprintf(output
+ slen
, outbufsize
- slen
, "<operand%d>",
1418 output
[slen
] = '\0';
1419 if (segover
) { /* unused segment override */
1421 int count
= slen
+ 1;
1423 p
[count
+ 3] = p
[count
];
1424 strncpy(output
, segover
, 2);
1431 * This is called when we don't have a complete instruction. If it
1432 * is a standalone *single-byte* prefix show it as such, otherwise
1433 * print it as a literal.
1435 int32_t eatbyte(uint8_t *data
, char *output
, int outbufsize
, int segsize
)
1437 uint8_t byte
= *data
;
1438 const char *str
= NULL
;
1472 str
= (segsize
== 16) ? "o32" : "o16";
1475 str
= (segsize
== 32) ? "a16" : "a32";
1493 if (segsize
== 64) {
1494 snprintf(output
, outbufsize
, "rex%s%s%s%s%s",
1495 (byte
== REX_P
) ? "" : ".",
1496 (byte
& REX_W
) ? "w" : "",
1497 (byte
& REX_R
) ? "r" : "",
1498 (byte
& REX_X
) ? "x" : "",
1499 (byte
& REX_B
) ? "b" : "");
1502 /* else fall through */
1504 snprintf(output
, outbufsize
, "db 0x%02x", byte
);
1509 snprintf(output
, outbufsize
, "%s", str
);