1 /* disasm.c where all the _work_ gets done in the Netwide Disassembler
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.
8 * initial version 27/iii/95 by Simon Tatham
26 * Flags that go into the `segment' field of `insn' structures
29 #define SEG_RELATIVE 1
36 #define SEG_SIGNED 128
45 uint8_t osize
; /* Operand size */
46 uint8_t asize
; /* Address size */
47 uint8_t osp
; /* Operand size prefix present */
48 uint8_t asp
; /* Address size prefix present */
49 uint8_t rep
; /* Rep prefix present */
50 uint8_t seg
; /* Segment override prefix present */
51 uint8_t lock
; /* Lock prefix present */
52 uint8_t rex
; /* Rex prefix present */
55 #define getu8(x) (*(uint8_t *)(x))
56 #if defined(__i386__) || defined(__x86_64__)
57 /* Littleendian CPU which can handle unaligned references */
58 #define getu16(x) (*(uint16_t *)(x))
59 #define getu32(x) (*(uint32_t *)(x))
60 #define getu64(x) (*(uint64_t *)(x))
62 static uint16_t getu16(uint8_t *data
)
64 return (uint16_t)data
[0] + ((uint16_t)data
[1] << 8);
66 static uint32_t getu32(uint8_t *data
)
68 return (uint32_t)getu16(data
) + ((uint32_t)getu16(data
+2) << 16);
70 static uint64_t getu64(uint8_t *data
)
72 return (uint64_t)getu32(data
) + ((uint64_t)getu32(data
+4) << 32);
76 #define gets8(x) ((int8_t)getu8(x))
77 #define gets16(x) ((int16_t)getu16(x))
78 #define gets32(x) ((int32_t)getu32(x))
79 #define gets64(x) ((int64_t)getu64(x))
81 /* Important: regval must already have been adjusted for rex extensions */
82 static enum reg_enum
whichreg(int32_t regflags
, int regval
, int rex
)
84 if (!(regflags
& (REGISTER
|REGMEM
)))
85 return 0; /* Registers not permissible?! */
89 if (!(REG_AL
& ~regflags
))
91 if (!(REG_AX
& ~regflags
))
93 if (!(REG_EAX
& ~regflags
))
95 if (!(REG_RAX
& ~regflags
))
97 if (!(REG_DL
& ~regflags
))
99 if (!(REG_DX
& ~regflags
))
101 if (!(REG_EDX
& ~regflags
))
103 if (!(REG_RDX
& ~regflags
))
105 if (!(REG_CL
& ~regflags
))
107 if (!(REG_CX
& ~regflags
))
109 if (!(REG_ECX
& ~regflags
))
111 if (!(REG_RCX
& ~regflags
))
113 if (!(FPU0
& ~regflags
))
115 if (!(REG_CS
& ~regflags
))
116 return (regval
== 1) ? R_CS
: 0;
117 if (!(REG_DESS
& ~regflags
))
118 return (regval
== 0 || regval
== 2
119 || regval
== 3 ? rd_sreg
[regval
] : 0);
120 if (!(REG_FSGS
& ~regflags
))
121 return (regval
== 4 || regval
== 5 ? rd_sreg
[regval
] : 0);
122 if (!(REG_SEG67
& ~regflags
))
123 return (regval
== 6 || regval
== 7 ? rd_sreg
[regval
] : 0);
125 /* All the entries below look up regval in an 16-entry array */
126 if (regval
< 0 || regval
> 15)
129 if (!(REG8
& ~regflags
)) {
131 return rd_reg8_rex
[regval
];
133 return rd_reg8
[regval
];
135 if (!(REG16
& ~regflags
))
136 return rd_reg16
[regval
];
137 if (!(REG32
& ~regflags
))
138 return rd_reg32
[regval
];
139 if (!(REG64
& ~regflags
))
140 return rd_reg64
[regval
];
141 if (!(REG_SREG
& ~regflags
))
142 return rd_sreg
[regval
& 7]; /* Ignore REX */
143 if (!(REG_CREG
& ~regflags
))
144 return rd_creg
[regval
];
145 if (!(REG_DREG
& ~regflags
))
146 return rd_dreg
[regval
];
147 if (!(REG_TREG
& ~regflags
)) {
149 return 0; /* TR registers are ill-defined with rex */
150 return rd_treg
[regval
];
152 if (!(FPUREG
& ~regflags
))
153 return rd_fpureg
[regval
& 7]; /* Ignore REX */
154 if (!(MMXREG
& ~regflags
))
155 return rd_mmxreg
[regval
& 7]; /* Ignore REX */
156 if (!(XMMREG
& ~regflags
))
157 return rd_xmmreg
[regval
];
162 static const char *whichcond(int condval
)
164 static int conds
[] = {
165 C_O
, C_NO
, C_C
, C_NC
, C_Z
, C_NZ
, C_NA
, C_A
,
166 C_S
, C_NS
, C_PE
, C_PO
, C_L
, C_NL
, C_NG
, C_G
168 return conditions
[conds
[condval
]];
172 * Process a DREX suffix
174 static uint8_t *do_drex(uint8_t *data
, insn
*ins
)
176 uint8_t drex
= *data
++;
177 operand
*dst
= &ins
->oprs
[ins
->drexdst
];
179 if ((drex
& 8) != ((ins
->rex
& REX_OC
) ? 8 : 0))
180 return NULL
; /* OC0 mismatch */
181 ins
->rex
= (ins
->rex
& ~7) | (drex
& 7);
183 dst
->segment
= SEG_RMREG
;
184 dst
->basereg
= drex
>> 4;
190 * Process an effective address (ModRM) specification.
192 static uint8_t *do_ea(uint8_t *data
, int modrm
, int asize
,
193 int segsize
, operand
* op
, insn
*ins
)
195 int mod
, rm
, scale
, index
, base
;
199 mod
= (modrm
>> 6) & 03;
202 if (mod
!= 3 && rm
== 4 && asize
!= 16)
205 if (ins
->rex
& REX_D
) {
206 data
= do_drex(data
, ins
);
212 if (mod
== 3) { /* pure register version */
213 op
->basereg
= rm
+(rex
& REX_B
? 8 : 0);
214 op
->segment
|= SEG_RMREG
;
223 * <mod> specifies the displacement size (none, byte or
224 * word), and <rm> specifies the register combination.
225 * Exception: mod=0,rm=6 does not specify [BP] as one might
226 * expect, but instead specifies [disp16].
228 op
->indexreg
= op
->basereg
= -1;
229 op
->scale
= 1; /* always, in 16 bits */
260 if (rm
== 6 && mod
== 0) { /* special case */
264 mod
= 2; /* fake disp16 */
268 op
->segment
|= SEG_NODISP
;
271 op
->segment
|= SEG_DISP8
;
272 op
->offset
= (int8_t)*data
++;
275 op
->segment
|= SEG_DISP16
;
276 op
->offset
= *data
++;
277 op
->offset
|= ((unsigned)*data
++) << 8;
283 * Once again, <mod> specifies displacement size (this time
284 * none, byte or *dword*), while <rm> specifies the base
285 * register. Again, [EBP] is missing, replaced by a pure
286 * disp32 (this time that's mod=0,rm=*5*) in 32-bit mode,
287 * and RIP-relative addressing in 64-bit mode.
290 * indicates not a single base register, but instead the
291 * presence of a SIB byte...
293 int a64
= asize
== 64;
298 op
->basereg
= rd_reg64
[rm
| ((rex
& REX_B
) ? 8 : 0)];
300 op
->basereg
= rd_reg32
[rm
| ((rex
& REX_B
) ? 8 : 0)];
302 if (rm
== 5 && mod
== 0) {
304 op
->eaflags
|= EAF_REL
;
305 op
->segment
|= SEG_RELATIVE
;
306 mod
= 2; /* fake disp32 */
310 op
->disp_size
= asize
;
313 mod
= 2; /* fake disp32 */
316 if (rm
== 4) { /* process SIB */
317 scale
= (sib
>> 6) & 03;
318 index
= (sib
>> 3) & 07;
321 op
->scale
= 1 << scale
;
324 op
->indexreg
= -1; /* ESP/RSP/R12 cannot be an index */
326 op
->indexreg
= rd_reg64
[index
| ((rex
& REX_X
) ? 8 : 0)];
328 op
->indexreg
= rd_reg64
[index
| ((rex
& REX_X
) ? 8 : 0)];
330 if (base
== 5 && mod
== 0) {
332 mod
= 2; /* Fake disp32 */
334 op
->basereg
= rd_reg64
[base
| ((rex
& REX_B
) ? 8 : 0)];
336 op
->basereg
= rd_reg32
[base
| ((rex
& REX_B
) ? 8 : 0)];
344 op
->segment
|= SEG_NODISP
;
347 op
->segment
|= SEG_DISP8
;
348 op
->offset
= gets8(data
);
352 op
->segment
|= SEG_DISP32
;
353 op
->offset
= getu32(data
);
362 * Determine whether the instruction template in t corresponds to the data
363 * stream in data. Return the number of bytes matched if so.
365 static int matches(const struct itemplate
*t
, uint8_t *data
,
366 const struct prefix_info
*prefix
, int segsize
, insn
*ins
)
368 uint8_t *r
= (uint8_t *)(t
->code
);
369 uint8_t *origdata
= data
;
370 bool a_used
= false, o_used
= false;
371 enum prefixes drep
= 0;
372 uint8_t lock
= prefix
->lock
;
373 int osize
= prefix
->osize
;
374 int asize
= prefix
->asize
;
377 for (i
= 0; i
< MAX_OPERANDS
; i
++) {
378 ins
->oprs
[i
].segment
= ins
->oprs
[i
].disp_size
=
379 (segsize
== 64 ? SEG_64BIT
: segsize
== 32 ? SEG_32BIT
: 0);
382 ins
->rex
= prefix
->rex
;
384 if (t
->flags
& (segsize
== 64 ? IF_NOLONG
: IF_LONG
))
387 if (prefix
->rep
== 0xF2)
389 else if (prefix
->rep
== 0xF3)
395 /* FIX: change this into a switch */
396 if (c
>= 01 && c
<= 03) {
400 } else if (c
== 04) {
403 ins
->oprs
[0].basereg
= 0;
406 ins
->oprs
[0].basereg
= 2;
409 ins
->oprs
[0].basereg
= 3;
414 } else if (c
== 05) {
417 ins
->oprs
[0].basereg
= 4;
420 ins
->oprs
[0].basereg
= 5;
425 } else if (c
== 06) {
428 ins
->oprs
[0].basereg
= 0;
431 ins
->oprs
[0].basereg
= 1;
434 ins
->oprs
[0].basereg
= 2;
437 ins
->oprs
[0].basereg
= 3;
442 } else if (c
== 07) {
445 ins
->oprs
[0].basereg
= 4;
448 ins
->oprs
[0].basereg
= 5;
453 } else if (c
>= 010 && c
<= 013) {
454 int t
= *r
++, d
= *data
++;
455 if (d
< t
|| d
> t
+ 7)
458 ins
->oprs
[c
- 010].basereg
= (d
-t
)+
459 (ins
->rex
& REX_B
? 8 : 0);
460 ins
->oprs
[c
- 010].segment
|= SEG_RMREG
;
462 } else if (c
>= 014 && c
<= 017) {
463 ins
->oprs
[c
- 014].offset
= (int8_t)*data
++;
464 ins
->oprs
[c
- 014].segment
|= SEG_SIGNED
;
465 } else if (c
>= 020 && c
<= 023) {
466 ins
->oprs
[c
- 020].offset
= *data
++;
467 } else if (c
>= 024 && c
<= 027) {
468 ins
->oprs
[c
- 024].offset
= *data
++;
469 } else if (c
>= 030 && c
<= 033) {
470 ins
->oprs
[c
- 030].offset
= getu16(data
);
472 } else if (c
>= 034 && c
<= 037) {
474 ins
->oprs
[c
- 034].offset
= getu32(data
);
477 ins
->oprs
[c
- 034].offset
= getu16(data
);
480 if (segsize
!= asize
)
481 ins
->oprs
[c
- 034].disp_size
= asize
;
482 } else if (c
>= 040 && c
<= 043) {
483 ins
->oprs
[c
- 040].offset
= getu32(data
);
485 } else if (c
>= 044 && c
<= 047) {
488 ins
->oprs
[c
- 044].offset
= getu16(data
);
492 ins
->oprs
[c
- 044].offset
= getu32(data
);
496 ins
->oprs
[c
- 044].offset
= getu64(data
);
500 if (segsize
!= asize
)
501 ins
->oprs
[c
- 044].disp_size
= asize
;
502 } else if (c
>= 050 && c
<= 053) {
503 ins
->oprs
[c
- 050].offset
= gets8(data
++);
504 ins
->oprs
[c
- 050].segment
|= SEG_RELATIVE
;
505 } else if (c
>= 054 && c
<= 057) {
506 ins
->oprs
[c
- 054].offset
= getu64(data
);
508 } else if (c
>= 060 && c
<= 063) {
509 ins
->oprs
[c
- 060].offset
= gets16(data
);
511 ins
->oprs
[c
- 060].segment
|= SEG_RELATIVE
;
512 ins
->oprs
[c
- 060].segment
&= ~SEG_32BIT
;
513 } else if (c
>= 064 && c
<= 067) {
514 ins
->oprs
[c
- 064].segment
|= SEG_RELATIVE
;
516 ins
->oprs
[c
- 064].offset
= getu16(data
);
518 ins
->oprs
[c
- 064].segment
&= ~(SEG_32BIT
|SEG_64BIT
);
519 } else if (osize
== 32) {
520 ins
->oprs
[c
- 064].offset
= getu32(data
);
522 ins
->oprs
[c
- 064].segment
&= ~SEG_64BIT
;
523 ins
->oprs
[c
- 064].segment
|= SEG_32BIT
;
525 if (segsize
!= osize
) {
526 ins
->oprs
[c
- 064].type
=
527 (ins
->oprs
[c
- 064].type
& ~SIZE_MASK
)
528 | ((osize
== 16) ? BITS16
: BITS32
);
530 } else if (c
>= 070 && c
<= 073) {
531 ins
->oprs
[c
- 070].offset
= getu32(data
);
533 ins
->oprs
[c
- 070].segment
|= SEG_32BIT
| SEG_RELATIVE
;
534 } else if (c
>= 0100 && c
< 0140) {
536 ins
->oprs
[c
& 07].segment
|= SEG_RMREG
;
537 data
= do_ea(data
, modrm
, asize
, segsize
,
538 &ins
->oprs
[(c
>> 3) & 07], ins
);
541 ins
->oprs
[c
& 07].basereg
= ((modrm
>> 3)&7)+
542 (ins
->rex
& REX_R
? 8 : 0);
543 } else if (c
>= 0140 && c
<= 0143) {
544 ins
->oprs
[c
- 0140].offset
= getu16(data
);
546 } else if (c
>= 0150 && c
<= 0153) {
547 ins
->oprs
[c
- 0150].offset
= getu32(data
);
549 } else if (c
>= 0160 && c
<= 0167) {
550 ins
->rex
|= (c
& 4) ? REX_D
|REX_OC
: REX_D
;
551 ins
->drexdst
= c
& 3;
552 } else if (c
== 0170) {
555 } else if (c
== 0171) {
556 data
= do_drex(data
, ins
);
559 } else if (c
>= 0200 && c
<= 0277) {
561 if (((modrm
>> 3) & 07) != (c
& 07))
562 return false; /* spare field doesn't match up */
563 data
= do_ea(data
, modrm
, asize
, segsize
,
564 &ins
->oprs
[(c
>> 3) & 07], ins
);
567 } else if (c
== 0310) {
572 } else if (c
== 0311) {
577 } else if (c
== 0312) {
578 if (asize
!= segsize
)
582 } else if (c
== 0313) {
587 } else if (c
== 0320) {
592 } else if (c
== 0321) {
597 } else if (c
== 0322) {
598 if (osize
!= (segsize
== 16) ? 16 : 32)
602 } else if (c
== 0323) {
603 ins
->rex
|= REX_W
; /* 64-bit only instruction */
605 } else if (c
== 0324) {
606 if (!(ins
->rex
& (REX_P
|REX_W
)) || osize
!= 64)
608 } else if (c
== 0330) {
609 int t
= *r
++, d
= *data
++;
610 if (d
< t
|| d
> t
+ 15)
613 ins
->condition
= d
- t
;
614 } else if (c
== 0331) {
617 } else if (c
== 0332) {
618 if (prefix
->rep
!= 0xF2)
620 } else if (c
== 0333) {
621 if (prefix
->rep
!= 0xF3)
624 } else if (c
== 0334) {
629 } else if (c
== 0335) {
632 } else if (c
== 0364) {
635 } else if (c
== 0365) {
638 } else if (c
== 0366) {
642 } else if (c
== 0367) {
649 /* REX cannot be combined with DREX */
650 if ((ins
->rex
& REX_D
) && (prefix
->rex
))
654 * Check for unused rep or a/o prefixes.
656 for (i
= 0; i
< t
->operands
; i
++) {
657 if (ins
->oprs
[i
].segment
!= SEG_RMREG
)
662 if (ins
->prefixes
[PPS_LREP
])
664 ins
->prefixes
[PPS_LREP
] = P_LOCK
;
667 if (ins
->prefixes
[PPS_LREP
])
669 ins
->prefixes
[PPS_LREP
] = drep
;
671 if (!o_used
&& osize
== ((segsize
== 16) ? 32 : 16)) {
672 if (ins
->prefixes
[PPS_OSIZE
])
674 ins
->prefixes
[PPS_OSIZE
] = osize
== 16 ? P_O16
: P_O32
;
676 if (!a_used
&& asize
!= segsize
) {
677 if (ins
->prefixes
[PPS_ASIZE
])
679 ins
->prefixes
[PPS_ASIZE
] = asize
== 16 ? P_A16
: P_A32
;
682 /* Fix: check for redundant REX prefixes */
684 return data
- origdata
;
687 int32_t disasm(uint8_t *data
, char *output
, int outbufsize
, int segsize
,
688 int32_t offset
, int autosync
, uint32_t prefer
)
690 const struct itemplate
* const *p
, * const *best_p
;
691 const struct disasm_index
*ix
;
693 int length
, best_length
= 0;
695 int i
, slen
, colon
, n
;
699 uint32_t goodness
, best
;
701 struct prefix_info prefix
;
703 memset(&ins
, 0, sizeof ins
);
708 memset(&prefix
, 0, sizeof prefix
);
709 prefix
.asize
= segsize
;
710 prefix
.osize
= (segsize
== 64) ? 32 : segsize
;
714 if (*data
== 0xF3 || *data
== 0xF2)
715 prefix
.rep
= *data
++;
716 else if (*data
== 0xF0)
717 prefix
.lock
= *data
++;
718 else if (*data
== 0x2E)
719 segover
= "cs", prefix
.seg
= *data
++;
720 else if (*data
== 0x36)
721 segover
= "ss", prefix
.seg
= *data
++;
722 else if (*data
== 0x3E)
723 segover
= "ds", prefix
.seg
= *data
++;
724 else if (*data
== 0x26)
725 segover
= "es", prefix
.seg
= *data
++;
726 else if (*data
== 0x64)
727 segover
= "fs", prefix
.seg
= *data
++;
728 else if (*data
== 0x65)
729 segover
= "gs", prefix
.seg
= *data
++;
730 else if (*data
== 0x66) {
731 prefix
.osize
= (segsize
== 16) ? 32 : 16;
732 prefix
.osp
= *data
++;
733 } else if (*data
== 0x67) {
734 prefix
.asize
= (segsize
== 32) ? 16 : 32;
735 prefix
.asp
= *data
++;
736 } else if (segsize
== 64 && (*data
& 0xf0) == REX_P
) {
737 prefix
.rex
= *data
++;
738 if (prefix
.rex
& REX_W
)
740 break; /* REX is always the last prefix */
746 best
= -1; /* Worst possible */
752 while (ix
->n
== -1) {
753 ix
= (const struct disasm_index
*)ix
->p
+ *dp
++;
756 p
= (const struct itemplate
* const *)ix
->p
;
757 for (n
= ix
->n
; n
; n
--, p
++) {
758 if ((length
= matches(*p
, data
, &prefix
, segsize
, &tmp_ins
))) {
761 * Final check to make sure the types of r/m match up.
762 * XXX: Need to make sure this is actually correct.
764 for (i
= 0; i
< (*p
)->operands
; i
++) {
765 if (!((*p
)->opd
[i
] & SAME_AS
) &&
767 /* If it's a mem-only EA but we have a register, die. */
768 ((tmp_ins
.oprs
[i
].segment
& SEG_RMREG
) &&
769 !(MEMORY
& ~(*p
)->opd
[i
])) ||
770 /* If it's a reg-only EA but we have a memory ref, die. */
771 (!(tmp_ins
.oprs
[i
].segment
& SEG_RMREG
) &&
772 !(REG_EA
& ~(*p
)->opd
[i
]) &&
773 !((*p
)->opd
[i
] & REG_SMASK
)) ||
774 /* Register type mismatch (eg FS vs REG_DESS): die. */
775 ((((*p
)->opd
[i
] & (REGISTER
| FPUREG
)) ||
776 (tmp_ins
.oprs
[i
].segment
& SEG_RMREG
)) &&
777 !whichreg((*p
)->opd
[i
],
778 tmp_ins
.oprs
[i
].basereg
, tmp_ins
.rex
))
786 * Note: we always prefer instructions which incorporate
787 * prefixes in the instructions themselves. This is to allow
788 * e.g. PAUSE to be preferred to REP NOP, and deal with
789 * MMX/SSE instructions where prefixes are used to select
790 * between MMX and SSE register sets or outright opcode
795 goodness
= ((*p
)->flags
& IF_PFMASK
) ^ prefer
;
797 for (i
= 0; i
< MAXPREFIX
; i
++)
798 if (tmp_ins
.prefixes
[i
])
800 if (nprefix
< best_pref
||
801 (nprefix
== best_pref
&& goodness
< best
)) {
802 /* This is the best one found so far */
806 best_length
= length
;
814 return 0; /* no instruction was matched */
816 /* Pick the best match */
818 length
= best_length
;
822 /* TODO: snprintf returns the value that the string would have if
823 * the buffer were long enough, and not the actual length of
824 * the returned string, so each instance of using the return
825 * value of snprintf should actually be checked to assure that
826 * the return value is "sane." Maybe a macro wrapper could
827 * be used for that purpose.
829 for (i
= 0; i
< MAXPREFIX
; i
++)
830 switch (ins
.prefixes
[i
]) {
832 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "lock ");
835 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "rep ");
838 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "repe ");
841 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "repne ");
844 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "a16 ");
847 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "a32 ");
850 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "o16 ");
853 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "o32 ");
859 for (i
= 0; i
< (int)elements(ico
); i
++)
860 if ((*p
)->opcode
== ico
[i
]) {
862 snprintf(output
+ slen
, outbufsize
- slen
, "%s%s", icn
[i
],
863 whichcond(ins
.condition
));
866 if (i
>= (int)elements(ico
))
868 snprintf(output
+ slen
, outbufsize
- slen
, "%s",
869 insn_names
[(*p
)->opcode
]);
871 length
+= data
- origdata
; /* fix up for prefixes */
872 for (i
= 0; i
< (*p
)->operands
; i
++) {
873 opflags_t t
= (*p
)->opd
[i
];
874 const operand
*o
= &ins
.oprs
[i
];
878 o
= &ins
.oprs
[t
& ~SAME_AS
];
879 t
= (*p
)->opd
[t
& ~SAME_AS
];
882 output
[slen
++] = (colon
? ':' : i
== 0 ? ' ' : ',');
885 if (o
->segment
& SEG_RELATIVE
) {
886 offs
+= offset
+ length
;
888 * sort out wraparound
890 if (!(o
->segment
& (SEG_32BIT
|SEG_64BIT
)))
893 * add sync marker, if autosync is on
904 if ((t
& (REGISTER
| FPUREG
)) ||
905 (o
->segment
& SEG_RMREG
)) {
907 reg
= whichreg(t
, o
->basereg
, ins
.rex
);
909 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "to ");
910 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
911 reg_names
[reg
- EXPR_REG_START
]);
912 } else if (!(UNITY
& ~t
)) {
913 output
[slen
++] = '1';
914 } else if (t
& IMMEDIATE
) {
917 snprintf(output
+ slen
, outbufsize
- slen
, "byte ");
918 if (o
->segment
& SEG_SIGNED
) {
921 output
[slen
++] = '-';
923 output
[slen
++] = '+';
925 } else if (t
& BITS16
) {
927 snprintf(output
+ slen
, outbufsize
- slen
, "word ");
928 } else if (t
& BITS32
) {
930 snprintf(output
+ slen
, outbufsize
- slen
, "dword ");
931 } else if (t
& BITS64
) {
933 snprintf(output
+ slen
, outbufsize
- slen
, "qword ");
934 } else if (t
& NEAR
) {
936 snprintf(output
+ slen
, outbufsize
- slen
, "near ");
937 } else if (t
& SHORT
) {
939 snprintf(output
+ slen
, outbufsize
- slen
, "short ");
942 snprintf(output
+ slen
, outbufsize
- slen
, "0x%"PRIx64
"",
944 } else if (!(MEM_OFFS
& ~t
)) {
946 snprintf(output
+ slen
, outbufsize
- slen
, "[%s%s%s0x%"PRIx64
"]",
947 (segover
? segover
: ""),
948 (segover
? ":" : ""),
950 32 ? "dword " : o
->disp_size
==
951 16 ? "word " : ""), offs
);
953 } else if (!(REGMEM
& ~t
)) {
957 snprintf(output
+ slen
, outbufsize
- slen
, "byte ");
960 snprintf(output
+ slen
, outbufsize
- slen
, "word ");
963 snprintf(output
+ slen
, outbufsize
- slen
, "dword ");
966 snprintf(output
+ slen
, outbufsize
- slen
, "qword ");
969 snprintf(output
+ slen
, outbufsize
- slen
, "tword ");
971 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "far ");
974 snprintf(output
+ slen
, outbufsize
- slen
, "near ");
975 output
[slen
++] = '[';
977 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
978 (o
->disp_size
== 64 ? "qword " :
979 o
->disp_size
== 32 ? "dword " :
980 o
->disp_size
== 16 ? "word " :
982 if (o
->eaflags
& EAF_REL
)
983 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "rel ");
986 snprintf(output
+ slen
, outbufsize
- slen
, "%s:",
990 if (o
->basereg
!= -1) {
991 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
992 reg_names
[(o
->basereg
-
996 if (o
->indexreg
!= -1) {
998 output
[slen
++] = '+';
999 slen
+= snprintf(output
+ slen
, outbufsize
- slen
, "%s",
1000 reg_names
[(o
->indexreg
-
1004 snprintf(output
+ slen
, outbufsize
- slen
, "*%d",
1008 if (o
->segment
& SEG_DISP8
) {
1010 int8_t offset
= offs
;
1016 snprintf(output
+ slen
, outbufsize
- slen
, "%s0x%"PRIx8
"",
1017 minus
? "-" : "+", offset
);
1018 } else if (o
->segment
& SEG_DISP16
) {
1020 int16_t offset
= offs
;
1026 snprintf(output
+ slen
, outbufsize
- slen
, "%s0x%"PRIx16
"",
1027 minus
? "-" : started
? "+" : "", offset
);
1028 } else if (o
->segment
& SEG_DISP32
) {
1030 int32_t offset
= offs
;
1035 prefix
= started
? "+" : "";
1038 snprintf(output
+ slen
, outbufsize
- slen
,
1039 "%s0x%"PRIx32
"", prefix
, offset
);
1041 output
[slen
++] = ']';
1044 snprintf(output
+ slen
, outbufsize
- slen
, "<operand%d>",
1048 output
[slen
] = '\0';
1049 if (segover
) { /* unused segment override */
1051 int count
= slen
+ 1;
1053 p
[count
+ 3] = p
[count
];
1054 strncpy(output
, segover
, 2);
1060 int32_t eatbyte(uint8_t *data
, char *output
, int outbufsize
)
1062 snprintf(output
, outbufsize
, "db 0x%02X", *data
);