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nasm/disasm.c
H. Peter Anvin 6867acc18e Use the compiler-provided booleans if available, otherwise emulate 
Both C and C++ have "bool", "true" and "false" in lower case; C
requires <stdbool.h> for this, in C++ it is an inherent type built
into the compiler.  Use those instead of the old macros; emulate with
a simple typedef enum if unavailable.
2007-10-10 14:58:45 -07:00

1048 lines
31 KiB
C
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/* disasm.c where all the _work_ gets done in the Netwide Disassembler
*
* The Netwide Assembler is copyright (C) 1996 Simon Tatham and
* Julian Hall. All rights reserved. The software is
* redistributable under the licence given in the file "Licence"
* distributed in the NASM archive.
*
* initial version 27/iii/95 by Simon Tatham
*/
#include "compiler.h"
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <inttypes.h>
#include "nasm.h"
#include "disasm.h"
#include "sync.h"
#include "insns.h"
#include "names.c"
/*
* Flags that go into the `segment' field of `insn' structures
* during disassembly.
*/
#define SEG_RELATIVE 1
#define SEG_32BIT 2
#define SEG_RMREG 4
#define SEG_DISP8 8
#define SEG_DISP16 16
#define SEG_DISP32 32
#define SEG_NODISP 64
#define SEG_SIGNED 128
#define SEG_64BIT 256
#include "regdis.c"
/*
* Prefix information
*/
struct prefix_info {
uint8_t osize; /* Operand size */
uint8_t asize; /* Address size */
uint8_t osp; /* Operand size prefix present */
uint8_t asp; /* Address size prefix present */
uint8_t rep; /* Rep prefix present */
uint8_t seg; /* Segment override prefix present */
uint8_t lock; /* Lock prefix present */
uint8_t rex; /* Rex prefix present */
};
#define getu8(x) (*(uint8_t *)(x))
#if defined(__i386__) || defined(__x86_64__)
/* Littleendian CPU which can handle unaligned references */
#define getu16(x) (*(uint16_t *)(x))
#define getu32(x) (*(uint32_t *)(x))
#define getu64(x) (*(uint64_t *)(x))
#else
static uint16_t getu16(uint8_t *data)
{
return (uint16_t)data[0] + ((uint16_t)data[1] << 8);
}
static uint32_t getu32(uint8_t *data)
{
return (uint32_t)getu16(data) + ((uint32_t)getu16(data+2) << 16);
}
static uint64_t getu64(uint8_t *data)
{
return (uint64_t)getu32(data) + ((uint64_t)getu32(data+4) << 32);
}
#endif
#define gets8(x) ((int8_t)getu8(x))
#define gets16(x) ((int16_t)getu16(x))
#define gets32(x) ((int32_t)getu32(x))
#define gets64(x) ((int64_t)getu64(x))
/* Important: regval must already have been adjusted for rex extensions */
static enum reg_enum whichreg(int32_t regflags, int regval, int rex)
{
if (!(regflags & (REGISTER|REGMEM)))
return 0; /* Registers not permissible?! */
regflags |= REGISTER;
if (!(REG_AL & ~regflags))
return R_AL;
if (!(REG_AX & ~regflags))
return R_AX;
if (!(REG_EAX & ~regflags))
return R_EAX;
if (!(REG_RAX & ~regflags))
return R_RAX;
if (!(REG_DL & ~regflags))
return R_DL;
if (!(REG_DX & ~regflags))
return R_DX;
if (!(REG_EDX & ~regflags))
return R_EDX;
if (!(REG_RDX & ~regflags))
return R_RDX;
if (!(REG_CL & ~regflags))
return R_CL;
if (!(REG_CX & ~regflags))
return R_CX;
if (!(REG_ECX & ~regflags))
return R_ECX;
if (!(REG_RCX & ~regflags))
return R_RCX;
if (!(FPU0 & ~regflags))
return R_ST0;
if (!(REG_CS & ~regflags))
return (regval == 1) ? R_CS : 0;
if (!(REG_DESS & ~regflags))
return (regval == 0 || regval == 2
|| regval == 3 ? rd_sreg[regval] : 0);
if (!(REG_FSGS & ~regflags))
return (regval == 4 || regval == 5 ? rd_sreg[regval] : 0);
if (!(REG_SEG67 & ~regflags))
return (regval == 6 || regval == 7 ? rd_sreg[regval] : 0);
/* All the entries below look up regval in an 16-entry array */
if (regval < 0 || regval > 15)
return 0;
if (!(REG8 & ~regflags)) {
if (rex & REX_P)
return rd_reg8_rex[regval];
else
return rd_reg8[regval];
}
if (!(REG16 & ~regflags))
return rd_reg16[regval];
if (!(REG32 & ~regflags))
return rd_reg32[regval];
if (!(REG64 & ~regflags))
return rd_reg64[regval];
if (!(REG_SREG & ~regflags))
return rd_sreg[regval & 7]; /* Ignore REX */
if (!(REG_CREG & ~regflags))
return rd_creg[regval];
if (!(REG_DREG & ~regflags))
return rd_dreg[regval];
if (!(REG_TREG & ~regflags)) {
if (rex & REX_P)
return 0; /* TR registers are ill-defined with rex */
return rd_treg[regval];
}
if (!(FPUREG & ~regflags))
return rd_fpureg[regval & 7]; /* Ignore REX */
if (!(MMXREG & ~regflags))
return rd_mmxreg[regval & 7]; /* Ignore REX */
if (!(XMMREG & ~regflags))
return rd_xmmreg[regval];
return 0;
}
static const char *whichcond(int condval)
{
static int conds[] = {
C_O, C_NO, C_C, C_NC, C_Z, C_NZ, C_NA, C_A,
C_S, C_NS, C_PE, C_PO, C_L, C_NL, C_NG, C_G
};
return conditions[conds[condval]];
}
/*
* Process a DREX suffix
*/
static uint8_t *do_drex(uint8_t *data, insn *ins)
{
uint8_t drex = *data++;
operand *dst = &ins->oprs[ins->drexdst];
if ((drex & 8) != ((ins->rex & REX_OC) ? 8 : 0))
return NULL; /* OC0 mismatch */
ins->rex = (ins->rex & ~7) | (drex & 7);
dst->segment = SEG_RMREG;
dst->basereg = drex >> 4;
return data;
}
/*
* Process an effective address (ModRM) specification.
*/
static uint8_t *do_ea(uint8_t *data, int modrm, int asize,
int segsize, operand * op, insn *ins)
{
int mod, rm, scale, index, base;
int rex;
uint8_t sib = 0;
mod = (modrm >> 6) & 03;
rm = modrm & 07;
if (mod != 3 && rm == 4 && asize != 16)
sib = *data++;
if (ins->rex & REX_D) {
data = do_drex(data, ins);
if (!data)
return NULL;
}
rex = ins->rex;
if (mod == 3) { /* pure register version */
op->basereg = rm+(rex & REX_B ? 8 : 0);
op->segment |= SEG_RMREG;
return data;
}
op->addr_size = 0;
op->eaflags = 0;
if (asize == 16) {
/*
* <mod> specifies the displacement size (none, byte or
* word), and <rm> specifies the register combination.
* Exception: mod=0,rm=6 does not specify [BP] as one might
* expect, but instead specifies [disp16].
*/
op->indexreg = op->basereg = -1;
op->scale = 1; /* always, in 16 bits */
switch (rm) {
case 0:
op->basereg = R_BX;
op->indexreg = R_SI;
break;
case 1:
op->basereg = R_BX;
op->indexreg = R_DI;
break;
case 2:
op->basereg = R_BP;
op->indexreg = R_SI;
break;
case 3:
op->basereg = R_BP;
op->indexreg = R_DI;
break;
case 4:
op->basereg = R_SI;
break;
case 5:
op->basereg = R_DI;
break;
case 6:
op->basereg = R_BP;
break;
case 7:
op->basereg = R_BX;
break;
}
if (rm == 6 && mod == 0) { /* special case */
op->basereg = -1;
if (segsize != 16)
op->addr_size = 16;
mod = 2; /* fake disp16 */
}
switch (mod) {
case 0:
op->segment |= SEG_NODISP;
break;
case 1:
op->segment |= SEG_DISP8;
op->offset = (int8_t)*data++;
break;
case 2:
op->segment |= SEG_DISP16;
op->offset = *data++;
op->offset |= ((unsigned)*data++) << 8;
break;
}
return data;
} else {
/*
* Once again, <mod> specifies displacement size (this time
* none, byte or *dword*), while <rm> specifies the base
* register. Again, [EBP] is missing, replaced by a pure
* disp32 (this time that's mod=0,rm=*5*) in 32-bit mode,
* and RIP-relative addressing in 64-bit mode.
*
* However, rm=4
* indicates not a single base register, but instead the
* presence of a SIB byte...
*/
int a64 = asize == 64;
op->indexreg = -1;
if (a64)
op->basereg = rd_reg64[rm | ((rex & REX_B) ? 8 : 0)];
else
op->basereg = rd_reg32[rm | ((rex & REX_B) ? 8 : 0)];
if (rm == 5 && mod == 0) {
if (segsize == 64) {
op->eaflags |= EAF_REL;
op->segment |= SEG_RELATIVE;
mod = 2; /* fake disp32 */
}
if (asize != 64)
op->addr_size = asize;
op->basereg = -1;
mod = 2; /* fake disp32 */
}
if (rm == 4) { /* process SIB */
scale = (sib >> 6) & 03;
index = (sib >> 3) & 07;
base = sib & 07;
op->scale = 1 << scale;
if (index == 4)
op->indexreg = -1; /* ESP/RSP/R12 cannot be an index */
else if (a64)
op->indexreg = rd_reg64[index | ((rex & REX_X) ? 8 : 0)];
else
op->indexreg = rd_reg64[index | ((rex & REX_X) ? 8 : 0)];
if (base == 5 && mod == 0) {
op->basereg = -1;
mod = 2; /* Fake disp32 */
} else if (a64)
op->basereg = rd_reg64[base | ((rex & REX_B) ? 8 : 0)];
else
op->basereg = rd_reg32[base | ((rex & REX_B) ? 8 : 0)];
if (segsize != 32)
op->addr_size = 32;
}
switch (mod) {
case 0:
op->segment |= SEG_NODISP;
break;
case 1:
op->segment |= SEG_DISP8;
op->offset = gets8(data);
data++;
break;
case 2:
op->segment |= SEG_DISP32;
op->offset = getu32(data);
data += 4;
break;
}
return data;
}
}
/*
* Determine whether the instruction template in t corresponds to the data
* stream in data. Return the number of bytes matched if so.
*/
static int matches(const struct itemplate *t, uint8_t *data,
const struct prefix_info *prefix, int segsize, insn *ins)
{
uint8_t *r = (uint8_t *)(t->code);
uint8_t *origdata = data;
bool a_used = false, o_used = false;
enum prefixes drep = 0;
uint8_t lock = prefix->lock;
int osize = prefix->osize;
int asize = prefix->asize;
int i;
for (i = 0; i < MAX_OPERANDS; i++) {
ins->oprs[i].segment = ins->oprs[i].addr_size =
(segsize == 64 ? SEG_64BIT : segsize == 32 ? SEG_32BIT : 0);
}
ins->condition = -1;
ins->rex = prefix->rex;
if (t->flags & (segsize == 64 ? IF_NOLONG : IF_LONG))
return false;
if (prefix->rep == 0xF2)
drep = P_REPNE;
else if (prefix->rep == 0xF3)
drep = P_REP;
while (*r) {
int c = *r++;
/* FIX: change this into a switch */
if (c >= 01 && c <= 03) {
while (c--)
if (*r++ != *data++)
return false;
} else if (c == 04) {
switch (*data++) {
case 0x07:
ins->oprs[0].basereg = 0;
break;
case 0x17:
ins->oprs[0].basereg = 2;
break;
case 0x1F:
ins->oprs[0].basereg = 3;
break;
default:
return false;
}
} else if (c == 05) {
switch (*data++) {
case 0xA1:
ins->oprs[0].basereg = 4;
break;
case 0xA9:
ins->oprs[0].basereg = 5;
break;
default:
return false;
}
} else if (c == 06) {
switch (*data++) {
case 0x06:
ins->oprs[0].basereg = 0;
break;
case 0x0E:
ins->oprs[0].basereg = 1;
break;
case 0x16:
ins->oprs[0].basereg = 2;
break;
case 0x1E:
ins->oprs[0].basereg = 3;
break;
default:
return false;
}
} else if (c == 07) {
switch (*data++) {
case 0xA0:
ins->oprs[0].basereg = 4;
break;
case 0xA8:
ins->oprs[0].basereg = 5;
break;
default:
return false;
}
} else if (c >= 010 && c <= 013) {
int t = *r++, d = *data++;
if (d < t || d > t + 7)
return false;
else {
ins->oprs[c - 010].basereg = (d-t)+
(ins->rex & REX_B ? 8 : 0);
ins->oprs[c - 010].segment |= SEG_RMREG;
}
} else if (c >= 014 && c <= 017) {
ins->oprs[c - 014].offset = (int8_t)*data++;
ins->oprs[c - 014].segment |= SEG_SIGNED;
} else if (c >= 020 && c <= 023) {
ins->oprs[c - 020].offset = *data++;
} else if (c >= 024 && c <= 027) {
ins->oprs[c - 024].offset = *data++;
} else if (c >= 030 && c <= 033) {
ins->oprs[c - 030].offset = getu16(data);
data += 2;
} else if (c >= 034 && c <= 037) {
if (osize == 32) {
ins->oprs[c - 034].offset = getu32(data);
data += 4;
} else {
ins->oprs[c - 034].offset = getu16(data);
data += 2;
}
if (segsize != asize)
ins->oprs[c - 034].addr_size = asize;
} else if (c >= 040 && c <= 043) {
ins->oprs[c - 040].offset = getu32(data);
data += 4;
} else if (c >= 044 && c <= 047) {
switch (asize) {
case 16:
ins->oprs[c - 044].offset = getu16(data);
data += 2;
break;
case 32:
ins->oprs[c - 044].offset = getu32(data);
data += 4;
break;
case 64:
ins->oprs[c - 044].offset = getu64(data);
data += 8;
break;
}
if (segsize != asize)
ins->oprs[c - 044].addr_size = asize;
} else if (c >= 050 && c <= 053) {
ins->oprs[c - 050].offset = gets8(data++);
ins->oprs[c - 050].segment |= SEG_RELATIVE;
} else if (c >= 054 && c <= 057) {
ins->oprs[c - 054].offset = getu64(data);
data += 8;
} else if (c >= 060 && c <= 063) {
ins->oprs[c - 060].offset = gets16(data);
data += 2;
ins->oprs[c - 060].segment |= SEG_RELATIVE;
ins->oprs[c - 060].segment &= ~SEG_32BIT;
} else if (c >= 064 && c <= 067) {
if (osize == 16) {
ins->oprs[c - 064].offset = getu16(data);
data += 2;
ins->oprs[c - 064].segment &= ~(SEG_32BIT|SEG_64BIT);
} else if (osize == 32) {
ins->oprs[c - 064].offset = getu32(data);
data += 4;
ins->oprs[c - 064].segment &= ~SEG_64BIT;
ins->oprs[c - 064].segment |= SEG_32BIT;
}
if (segsize != osize) {
ins->oprs[c - 064].type =
(ins->oprs[c - 064].type & ~SIZE_MASK)
| ((osize == 16) ? BITS16 : BITS32);
}
} else if (c >= 070 && c <= 073) {
ins->oprs[c - 070].offset = getu32(data);
data += 4;
ins->oprs[c - 070].segment |= SEG_32BIT | SEG_RELATIVE;
} else if (c >= 0100 && c < 0140) {
int modrm = *data++;
ins->oprs[c & 07].segment |= SEG_RMREG;
data = do_ea(data, modrm, asize, segsize,
&ins->oprs[(c >> 3) & 07], ins);
if (!data)
return false;
ins->oprs[c & 07].basereg = ((modrm >> 3)&7)+
(ins->rex & REX_R ? 8 : 0);
} else if (c >= 0140 && c <= 0143) {
ins->oprs[c - 0140].offset = getu16(data);
data += 2;
} else if (c >= 0150 && c <= 0153) {
ins->oprs[c - 0150].offset = getu32(data);
data += 4;
} else if (c >= 0160 && c <= 0167) {
ins->rex |= (c & 4) ? REX_D|REX_OC : REX_D;
ins->drexdst = c & 3;
} else if (c == 0170) {
if (*data++)
return false;
} else if (c == 0171) {
data = do_drex(data, ins);
if (!data)
return false;
} else if (c >= 0200 && c <= 0277) {
int modrm = *data++;
if (((modrm >> 3) & 07) != (c & 07))
return false; /* spare field doesn't match up */
data = do_ea(data, modrm, asize, segsize,
&ins->oprs[(c >> 3) & 07], ins);
if (!data)
return false;
} else if (c == 0310) {
if (asize != 16)
return false;
else
a_used = true;
} else if (c == 0311) {
if (asize == 16)
return false;
else
a_used = true;
} else if (c == 0312) {
if (asize != segsize)
return false;
else
a_used = true;
} else if (c == 0313) {
if (asize != 64)
return false;
else
a_used = true;
} else if (c == 0320) {
if (osize != 16)
return false;
else
o_used = true;
} else if (c == 0321) {
if (osize != 32)
return false;
else
o_used = true;
} else if (c == 0322) {
if (osize != (segsize == 16) ? 16 : 32)
return false;
else
o_used = true;
} else if (c == 0323) {
ins->rex |= REX_W; /* 64-bit only instruction */
osize = 64;
} else if (c == 0324) {
if (!(ins->rex & (REX_P|REX_W)) || osize != 64)
return false;
} else if (c == 0330) {
int t = *r++, d = *data++;
if (d < t || d > t + 15)
return false;
else
ins->condition = d - t;
} else if (c == 0331) {
if (prefix->rep)
return false;
} else if (c == 0332) {
if (prefix->rep != 0xF2)
return false;
} else if (c == 0333) {
if (prefix->rep != 0xF3)
return false;
drep = 0;
} else if (c == 0334) {
if (lock) {
ins->rex |= REX_R;
lock = 0;
}
} else if (c == 0335) {
if (drep == P_REP)
drep = P_REPE;
} else if (c == 0364) {
if (prefix->osp)
return false;
} else if (c == 0365) {
if (prefix->asp)
return false;
} else if (c == 0366) {
if (!prefix->osp)
return false;
o_used = true;
} else if (c == 0367) {
if (!prefix->asp)
return false;
o_used = true;
}
}
/* REX cannot be combined with DREX */
if ((ins->rex & REX_D) && (prefix->rex))
return false;
/*
* Check for unused rep or a/o prefixes.
*/
for (i = 0; i < t->operands; i++) {
if (ins->oprs[i].segment != SEG_RMREG)
a_used = true;
}
ins->nprefix = 0;
if (lock)
ins->prefixes[ins->nprefix++] = P_LOCK;
if (drep)
ins->prefixes[ins->nprefix++] = drep;
if (!a_used && asize != segsize)
ins->prefixes[ins->nprefix++] = asize == 16 ? P_A16 : P_A32;
if (!o_used && osize == ((segsize == 16) ? 32 : 16))
ins->prefixes[ins->nprefix++] = osize == 16 ? P_O16 : P_O32;
/* Fix: check for redundant REX prefixes */
return data - origdata;
}
int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize,
int32_t offset, int autosync, uint32_t prefer)
{
const struct itemplate * const *p, * const *best_p;
const struct disasm_index *ix;
uint8_t *dp;
int length, best_length = 0;
char *segover;
int i, slen, colon, n;
uint8_t *origdata;
int works;
insn tmp_ins, ins;
uint32_t goodness, best;
int best_pref;
struct prefix_info prefix;
memset(&ins, 0, sizeof ins);
/*
* Scan for prefixes.
*/
memset(&prefix, 0, sizeof prefix);
prefix.asize = segsize;
prefix.osize = (segsize == 64) ? 32 : segsize;
segover = NULL;
origdata = data;
for (;;) {
if (*data == 0xF3 || *data == 0xF2)
prefix.rep = *data++;
else if (*data == 0xF0)
prefix.lock = *data++;
else if (*data == 0x2E)
segover = "cs", prefix.seg = *data++;
else if (*data == 0x36)
segover = "ss", prefix.seg = *data++;
else if (*data == 0x3E)
segover = "ds", prefix.seg = *data++;
else if (*data == 0x26)
segover = "es", prefix.seg = *data++;
else if (*data == 0x64)
segover = "fs", prefix.seg = *data++;
else if (*data == 0x65)
segover = "gs", prefix.seg = *data++;
else if (*data == 0x66) {
prefix.osize = (segsize == 16) ? 32 : 16;
prefix.osp = *data++;
} else if (*data == 0x67) {
prefix.asize = (segsize == 32) ? 16 : 32;
prefix.asp = *data++;
} else if (segsize == 64 && (*data & 0xf0) == REX_P) {
prefix.rex = *data++;
if (prefix.rex & REX_W)
prefix.osize = 64;
break; /* REX is always the last prefix */
} else {
break;
}
}
best = -1; /* Worst possible */
best_p = NULL;
best_pref = INT_MAX;
dp = data;
ix = itable + *dp++;
while (ix->n == (size_t)-1) {
ix = (const struct disasm_index *)ix->p + *dp++;
}
p = (const struct itemplate * const *)ix->p;
for (n = ix->n; n; n--, p++) {
if ((length = matches(*p, data, &prefix, segsize, &tmp_ins))) {
works = true;
/*
* Final check to make sure the types of r/m match up.
* XXX: Need to make sure this is actually correct.
*/
for (i = 0; i < (*p)->operands; i++) {
if (!((*p)->opd[i] & SAME_AS) &&
(
/* If it's a mem-only EA but we have a register, die. */
((tmp_ins.oprs[i].segment & SEG_RMREG) &&
!(MEMORY & ~(*p)->opd[i])) ||
/* If it's a reg-only EA but we have a memory ref, die. */
(!(tmp_ins.oprs[i].segment & SEG_RMREG) &&
!(REG_EA & ~(*p)->opd[i]) &&
!((*p)->opd[i] & REG_SMASK)) ||
/* Register type mismatch (eg FS vs REG_DESS): die. */
((((*p)->opd[i] & (REGISTER | FPUREG)) ||
(tmp_ins.oprs[i].segment & SEG_RMREG)) &&
!whichreg((*p)->opd[i],
tmp_ins.oprs[i].basereg, tmp_ins.rex))
)) {
works = false;
break;
}
}
/*
* Note: we always prefer instructions which incorporate
* prefixes in the instructions themselves. This is to allow
* e.g. PAUSE to be preferred to REP NOP, and deal with
* MMX/SSE instructions where prefixes are used to select
* between MMX and SSE register sets or outright opcode
* selection.
*/
if (works) {
goodness = ((*p)->flags & IF_PFMASK) ^ prefer;
if (tmp_ins.nprefix < best_pref ||
(tmp_ins.nprefix == best_pref && goodness < best)) {
/* This is the best one found so far */
best = goodness;
best_p = p;
best_pref = tmp_ins.nprefix;
best_length = length;
ins = tmp_ins;
}
}
}
}
if (!best_p)
return 0; /* no instruction was matched */
/* Pick the best match */
p = best_p;
length = best_length;
slen = 0;
/* TODO: snprintf returns the value that the string would have if
* the buffer were long enough, and not the actual length of
* the returned string, so each instance of using the return
* value of snprintf should actually be checked to assure that
* the return value is "sane." Maybe a macro wrapper could
* be used for that purpose.
*/
for (i = 0; i < ins.nprefix; i++)
switch (ins.prefixes[i]) {
case P_LOCK:
slen += snprintf(output + slen, outbufsize - slen, "lock ");
break;
case P_REP:
slen += snprintf(output + slen, outbufsize - slen, "rep ");
break;
case P_REPE:
slen += snprintf(output + slen, outbufsize - slen, "repe ");
break;
case P_REPNE:
slen += snprintf(output + slen, outbufsize - slen, "repne ");
break;
case P_A16:
slen += snprintf(output + slen, outbufsize - slen, "a16 ");
break;
case P_A32:
slen += snprintf(output + slen, outbufsize - slen, "a32 ");
break;
case P_O16:
slen += snprintf(output + slen, outbufsize - slen, "o16 ");
break;
case P_O32:
slen += snprintf(output + slen, outbufsize - slen, "o32 ");
break;
default:
break;
}
for (i = 0; i < (int)elements(ico); i++)
if ((*p)->opcode == ico[i]) {
slen +=
snprintf(output + slen, outbufsize - slen, "%s%s", icn[i],
whichcond(ins.condition));
break;
}
if (i >= (int)elements(ico))
slen +=
snprintf(output + slen, outbufsize - slen, "%s",
insn_names[(*p)->opcode]);
colon = false;
length += data - origdata; /* fix up for prefixes */
for (i = 0; i < (*p)->operands; i++) {
opflags_t t = (*p)->opd[i];
const operand *o = &ins.oprs[i];
int64_t offs;
if (t & SAME_AS) {
o = &ins.oprs[t & ~SAME_AS];
t = (*p)->opd[t & ~SAME_AS];
}
output[slen++] = (colon ? ':' : i == 0 ? ' ' : ',');
offs = o->offset;
if (o->segment & SEG_RELATIVE) {
offs += offset + length;
/*
* sort out wraparound
*/
if (!(o->segment & (SEG_32BIT|SEG_64BIT)))
offs &= 0xffff;
/*
* add sync marker, if autosync is on
*/
if (autosync)
add_sync(offs, 0L);
}
if (t & COLON)
colon = true;
else
colon = false;
if ((t & (REGISTER | FPUREG)) ||
(o->segment & SEG_RMREG)) {
enum reg_enum reg;
reg = whichreg(t, o->basereg, ins.rex);
if (t & TO)
slen += snprintf(output + slen, outbufsize - slen, "to ");
slen += snprintf(output + slen, outbufsize - slen, "%s",
reg_names[reg - EXPR_REG_START]);
} else if (!(UNITY & ~t)) {
output[slen++] = '1';
} else if (t & IMMEDIATE) {
if (t & BITS8) {
slen +=
snprintf(output + slen, outbufsize - slen, "byte ");
if (o->segment & SEG_SIGNED) {
if (offs < 0) {
offs *= -1;
output[slen++] = '-';
} else
output[slen++] = '+';
}
} else if (t & BITS16) {
slen +=
snprintf(output + slen, outbufsize - slen, "word ");
} else if (t & BITS32) {
slen +=
snprintf(output + slen, outbufsize - slen, "dword ");
} else if (t & BITS64) {
slen +=
snprintf(output + slen, outbufsize - slen, "qword ");
} else if (t & NEAR) {
slen +=
snprintf(output + slen, outbufsize - slen, "near ");
} else if (t & SHORT) {
slen +=
snprintf(output + slen, outbufsize - slen, "short ");
}
slen +=
snprintf(output + slen, outbufsize - slen, "0x%"PRIx64"",
offs);
} else if (!(MEM_OFFS & ~t)) {
slen +=
snprintf(output + slen, outbufsize - slen, "[%s%s%s0x%"PRIx64"]",
(segover ? segover : ""),
(segover ? ":" : ""),
(o->addr_size ==
32 ? "dword " : o->addr_size ==
16 ? "word " : ""), offs);
segover = NULL;
} else if (!(REGMEM & ~t)) {
int started = false;
if (t & BITS8)
slen +=
snprintf(output + slen, outbufsize - slen, "byte ");
if (t & BITS16)
slen +=
snprintf(output + slen, outbufsize - slen, "word ");
if (t & BITS32)
slen +=
snprintf(output + slen, outbufsize - slen, "dword ");
if (t & BITS64)
slen +=
snprintf(output + slen, outbufsize - slen, "qword ");
if (t & BITS80)
slen +=
snprintf(output + slen, outbufsize - slen, "tword ");
if (t & FAR)
slen += snprintf(output + slen, outbufsize - slen, "far ");
if (t & NEAR)
slen +=
snprintf(output + slen, outbufsize - slen, "near ");
output[slen++] = '[';
if (o->addr_size)
slen += snprintf(output + slen, outbufsize - slen, "%s",
(o->addr_size == 64 ? "qword " :
o->addr_size == 32 ? "dword " :
o->addr_size == 16 ? "word " :
""));
if (o->eaflags & EAF_REL)
slen += snprintf(output + slen, outbufsize - slen, "rel ");
if (segover) {
slen +=
snprintf(output + slen, outbufsize - slen, "%s:",
segover);
segover = NULL;
}
if (o->basereg != -1) {
slen += snprintf(output + slen, outbufsize - slen, "%s",
reg_names[(o->basereg -
EXPR_REG_START)]);
started = true;
}
if (o->indexreg != -1) {
if (started)
output[slen++] = '+';
slen += snprintf(output + slen, outbufsize - slen, "%s",
reg_names[(o->indexreg -
EXPR_REG_START)]);
if (o->scale > 1)
slen +=
snprintf(output + slen, outbufsize - slen, "*%d",
o->scale);
started = true;
}
if (o->segment & SEG_DISP8) {
int minus = 0;
int8_t offset = offs;
if (offset < 0) {
minus = 1;
offset = -offset;
}
slen +=
snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx8"",
minus ? "-" : "+", offset);
} else if (o->segment & SEG_DISP16) {
int minus = 0;
int16_t offset = offs;
if (offset < 0) {
minus = 1;
offset = -offset;
}
slen +=
snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx16"",
minus ? "-" : started ? "+" : "", offset);
} else if (o->segment & SEG_DISP32) {
char *prefix = "";
int32_t offset = offs;
if (offset < 0) {
offset = -offset;
prefix = "-";
} else {
prefix = started ? "+" : "";
}
slen +=
snprintf(output + slen, outbufsize - slen,
"%s0x%"PRIx32"", prefix, offset);
}
output[slen++] = ']';
} else {
slen +=
snprintf(output + slen, outbufsize - slen, "<operand%d>",
i);
}
}
output[slen] = '\0';
if (segover) { /* unused segment override */
char *p = output;
int count = slen + 1;
while (count--)
p[count + 3] = p[count];
strncpy(output, segover, 2);
output[2] = ' ';
}
return length;
}
int32_t eatbyte(uint8_t *data, char *output, int outbufsize)
{
snprintf(output, outbufsize, "db 0x%02X", *data);
return 1;
}
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