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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 <stdio.h>
#include <string.h>
#include "nasm.h"
#include "insns.h"
/* names.c included source file defining instruction and register
* names for the Netwide [Dis]Assembler
*
* 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.
*/
static const char *conditions[] = { /* condition code names */
"a", "ae", "b", "be", "c", "e", "g", "ge", "l", "le", "na", "nae",
"nb", "nbe", "nc", "ne", "ng", "nge", "nl", "nle", "no", "np",
"ns", "nz", "o", "p", "pe", "po", "s", "z"
};
/* Register names automatically generated from regs.dat */
/* automatically generated from ./regs.dat - do not edit */
static const char *reg_names[] = {
"ah",
"al",
"ax",
"bh",
"bl",
"bp",
"bx",
"ch",
"cl",
"cr0",
"cr1",
"cr2",
"cr3",
"cr4",
"cr5",
"cr6",
"cr7",
"cs",
"cx",
"dh",
"di",
"dl",
"dr0",
"dr1",
"dr2",
"dr3",
"dr4",
"dr5",
"dr6",
"dr7",
"ds",
"dx",
"eax",
"ebp",
"ebx",
"ecx",
"edi",
"edx",
"es",
"esi",
"esp",
"fs",
"gs",
"mm0",
"mm1",
"mm2",
"mm3",
"mm4",
"mm5",
"mm6",
"mm7",
"segr6",
"segr7",
"si",
"sp",
"ss",
"st0",
"st1",
"st2",
"st3",
"st4",
"st5",
"st6",
"st7",
"tr0",
"tr1",
"tr2",
"tr3",
"tr4",
"tr5",
"tr6",
"tr7",
"xmm0",
"xmm1",
"xmm2",
"xmm3",
"xmm4",
"xmm5",
"xmm6",
"xmm7"
};
/* Instruction names automatically generated from insns.dat */
/* This file is auto-generated from insns.dat by insns.pl - don't edit it */
/* This file in included by names.c */
static const char *insn_names[] = {
"aaa",
"aad",
"aam",
"aas",
"adc",
"add",
"addpd",
"addps",
"addsd",
"addss",
"addsubpd",
"addsubps",
"and",
"andnpd",
"andnps",
"andpd",
"andps",
"arpl",
"bound",
"bsf",
"bsr",
"bswap",
"bt",
"btc",
"btr",
"bts",
"call",
"cbw",
"cdq",
"clc",
"cld",
"clflush",
"cli",
"clts",
"cmc",
"cmp",
"cmpeqpd",
"cmpeqps",
"cmpeqsd",
"cmpeqss",
"cmplepd",
"cmpleps",
"cmplesd",
"cmpless",
"cmpltpd",
"cmpltps",
"cmpltsd",
"cmpltss",
"cmpneqpd",
"cmpneqps",
"cmpneqsd",
"cmpneqss",
"cmpnlepd",
"cmpnleps",
"cmpnlesd",
"cmpnless",
"cmpnltpd",
"cmpnltps",
"cmpnltsd",
"cmpnltss",
"cmpordpd",
"cmpordps",
"cmpordsd",
"cmpordss",
"cmppd",
"cmpps",
"cmpsb",
"cmpsd",
"cmpss",
"cmpsw",
"cmpunordpd",
"cmpunordps",
"cmpunordsd",
"cmpunordss",
"cmpxchg",
"cmpxchg486",
"cmpxchg8b",
"comisd",
"comiss",
"cpuid",
"cvtdq2pd",
"cvtdq2ps",
"cvtpd2dq",
"cvtpd2pi",
"cvtpd2ps",
"cvtpi2pd",
"cvtpi2ps",
"cvtps2dq",
"cvtps2pd",
"cvtps2pi",
"cvtsd2si",
"cvtsd2ss",
"cvtsi2sd",
"cvtsi2ss",
"cvtss2sd",
"cvtss2si",
"cvttpd2dq",
"cvttpd2pi",
"cvttps2dq",
"cvttps2pi",
"cvttsd2si",
"cvttss2si",
"cwd",
"cwde",
"daa",
"das",
"db",
"dd",
"dec",
"div",
"divpd",
"divps",
"divsd",
"divss",
"dq",
"dt",
"dw",
"emms",
"enter",
"equ",
"f2xm1",
"fabs",
"fadd",
"faddp",
"fbld",
"fbstp",
"fchs",
"fclex",
"fcmovb",
"fcmovbe",
"fcmove",
"fcmovnb",
"fcmovnbe",
"fcmovne",
"fcmovnu",
"fcmovu",
"fcom",
"fcomi",
"fcomip",
"fcomp",
"fcompp",
"fcos",
"fdecstp",
"fdisi",
"fdiv",
"fdivp",
"fdivr",
"fdivrp",
"femms",
"feni",
"ffree",
"ffreep",
"fiadd",
"ficom",
"ficomp",
"fidiv",
"fidivr",
"fild",
"fimul",
"fincstp",
"finit",
"fist",
"fistp",
"fisttp",
"fisub",
"fisubr",
"fld",
"fld1",
"fldcw",
"fldenv",
"fldl2e",
"fldl2t",
"fldlg2",
"fldln2",
"fldpi",
"fldz",
"fmul",
"fmulp",
"fnclex",
"fndisi",
"fneni",
"fninit",
"fnop",
"fnsave",
"fnstcw",
"fnstenv",
"fnstsw",
"fpatan",
"fprem",
"fprem1",
"fptan",
"frndint",
"frstor",
"fsave",
"fscale",
"fsetpm",
"fsin",
"fsincos",
"fsqrt",
"fst",
"fstcw",
"fstenv",
"fstp",
"fstsw",
"fsub",
"fsubp",
"fsubr",
"fsubrp",
"ftst",
"fucom",
"fucomi",
"fucomip",
"fucomp",
"fucompp",
"fwait",
"fxam",
"fxch",
"fxrstor",
"fxsave",
"fxtract",
"fyl2x",
"fyl2xp1",
"haddpd",
"haddps",
"hlt",
"hsubpd",
"hsubps",
"ibts",
"icebp",
"idiv",
"imul",
"in",
"inc",
"incbin",
"insb",
"insd",
"insw",
"int",
"int01",
"int03",
"int1",
"int3",
"into",
"invd",
"invlpg",
"iret",
"iretd",
"iretw",
"jcxz",
"jecxz",
"jmp",
"jmpe",
"lahf",
"lar",
"lddqu",
"ldmxcsr",
"lds",
"lea",
"leave",
"les",
"lfence",
"lfs",
"lgdt",
"lgs",
"lidt",
"lldt",
"lmsw",
"loadall",
"loadall286",
"lodsb",
"lodsd",
"lodsw",
"loop",
"loope",
"loopne",
"loopnz",
"loopz",
"lsl",
"lss",
"ltr",
"maskmovdqu",
"maskmovq",
"maxpd",
"maxps",
"maxsd",
"maxss",
"mfence",
"minpd",
"minps",
"minsd",
"minss",
"monitor",
"mov",
"movapd",
"movaps",
"movd",
"movddup",
"movdq2q",
"movdqa",
"movdqu",
"movhlps",
"movhpd",
"movhps",
"movlhps",
"movlpd",
"movlps",
"movmskpd",
"movmskps",
"movntdq",
"movnti",
"movntpd",
"movntps",
"movntq",
"movq",
"movq2dq",
"movsb",
"movsd",
"movshdup",
"movsldup",
"movss",
"movsw",
"movsx",
"movupd",
"movups",
"movzx",
"mul",
"mulpd",
"mulps",
"mulsd",
"mulss",
"mwait",
"neg",
"nop",
"not",
"or",
"orpd",
"orps",
"out",
"outsb",
"outsd",
"outsw",
"packssdw",
"packsswb",
"packuswb",
"paddb",
"paddd",
"paddq",
"paddsb",
"paddsiw",
"paddsw",
"paddusb",
"paddusw",
"paddw",
"pand",
"pandn",
"pause",
"paveb",
"pavgb",
"pavgusb",
"pavgw",
"pcmpeqb",
"pcmpeqd",
"pcmpeqw",
"pcmpgtb",
"pcmpgtd",
"pcmpgtw",
"pdistib",
"pextrw",
"pf2id",
"pf2iw",
"pfacc",
"pfadd",
"pfcmpeq",
"pfcmpge",
"pfcmpgt",
"pfmax",
"pfmin",
"pfmul",
"pfnacc",
"pfpnacc",
"pfrcp",
"pfrcpit1",
"pfrcpit2",
"pfrsqit1",
"pfrsqrt",
"pfsub",
"pfsubr",
"pi2fd",
"pi2fw",
"pinsrw",
"pmachriw",
"pmaddwd",
"pmagw",
"pmaxsw",
"pmaxub",
"pminsw",
"pminub",
"pmovmskb",
"pmulhriw",
"pmulhrwa",
"pmulhrwc",
"pmulhuw",
"pmulhw",
"pmullw",
"pmuludq",
"pmvgezb",
"pmvlzb",
"pmvnzb",
"pmvzb",
"pop",
"popa",
"popad",
"popaw",
"popf",
"popfd",
"popfw",
"por",
"prefetch",
"prefetchnta",
"prefetcht0",
"prefetcht1",
"prefetcht2",
"prefetchw",
"psadbw",
"pshufd",
"pshufhw",
"pshuflw",
"pshufw",
"pslld",
"pslldq",
"psllq",
"psllw",
"psrad",
"psraw",
"psrld",
"psrldq",
"psrlq",
"psrlw",
"psubb",
"psubd",
"psubq",
"psubsb",
"psubsiw",
"psubsw",
"psubusb",
"psubusw",
"psubw",
"pswapd",
"punpckhbw",
"punpckhdq",
"punpckhqdq",
"punpckhwd",
"punpcklbw",
"punpckldq",
"punpcklqdq",
"punpcklwd",
"push",
"pusha",
"pushad",
"pushaw",
"pushf",
"pushfd",
"pushfw",
"pxor",
"rcl",
"rcpps",
"rcpss",
"rcr",
"rdmsr",
"rdpmc",
"rdshr",
"rdtsc",
"resb",
"resd",
"resq",
"rest",
"resw",
"ret",
"retf",
"retn",
"rol",
"ror",
"rsdc",
"rsldt",
"rsm",
"rsqrtps",
"rsqrtss",
"rsts",
"sahf",
"sal",
"salc",
"sar",
"sbb",
"scasb",
"scasd",
"scasw",
"sfence",
"sgdt",
"shl",
"shld",
"shr",
"shrd",
"shufpd",
"shufps",
"sidt",
"sldt",
"smi",
"smint",
"smintold",
"smsw",
"sqrtpd",
"sqrtps",
"sqrtsd",
"sqrtss",
"stc",
"std",
"sti",
"stmxcsr",
"stosb",
"stosd",
"stosw",
"str",
"sub",
"subpd",
"subps",
"subsd",
"subss",
"svdc",
"svldt",
"svts",
"syscall",
"sysenter",
"sysexit",
"sysret",
"test",
"ucomisd",
"ucomiss",
"ud0",
"ud1",
"ud2",
"umov",
"unpckhpd",
"unpckhps",
"unpcklpd",
"unpcklps",
"verr",
"verw",
"wait",
"wbinvd",
"wrmsr",
"wrshr",
"xadd",
"xbts",
"xchg",
"xlat",
"xlatb",
"xor",
"xorpd",
"xorps",
"xstore"
};
/* Conditional instructions */
static const char *icn[] = {
"cmov",
"j",
"set"
};
/* and the corresponding opcodes */
static int ico[] = {
I_CMOVcc,
I_Jcc,
I_SETcc
};
#define INSN_MAX 32 /* one instruction can't be longer than this */
long disasm (unsigned char *data, char *output, int segsize, long offset);
extern struct itemplate **itable[];
/*
* 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
static int whichreg(long regflags, int regval)
{
/* automatically generated from ./regs.dat - do not edit */
static const int creg [] = {R_CR0,R_CR1,R_CR2,R_CR3,R_CR4,R_CR5,R_CR6,R_CR7};
static const int dreg [] = {R_DR0,R_DR1,R_DR2,R_DR3,R_DR4,R_DR5,R_DR6,R_DR7};
static const int fpureg [] = {R_ST0,R_ST1,R_ST2,R_ST3,R_ST4,R_ST5,R_ST6,R_ST7};
static const int mmxreg [] = {R_MM0,R_MM1,R_MM2,R_MM3,R_MM4,R_MM5,R_MM6,R_MM7};
static const int reg16 [] = {R_AX,R_CX,R_DX,R_BX,R_SP,R_BP,R_SI,R_DI};
static const int reg32 [] = {R_EAX,R_ECX,R_EDX,R_EBX,R_ESP,R_EBP,R_ESI,R_EDI};
static const int reg8 [] = {R_AL,R_CL,R_DL,R_BL,R_AH,R_CH,R_DH,R_BH};
static const int sreg [] = {R_ES,R_CS,R_SS,R_DS,R_FS,R_GS,R_SEGR6,R_SEGR7};
static const int treg [] = {R_TR0,R_TR1,R_TR2,R_TR3,R_TR4,R_TR5,R_TR6,R_TR7};
static const int xmmreg [] = {R_XMM0,R_XMM1,R_XMM2,R_XMM3,R_XMM4,R_XMM5,R_XMM6,R_XMM7};
if (!(REG_AL & ~regflags))
return R_AL;
if (!(REG_AX & ~regflags))
return R_AX;
if (!(REG_EAX & ~regflags))
return R_EAX;
if (!(REG_DL & ~regflags))
return R_DL;
if (!(REG_DX & ~regflags))
return R_DX;
if (!(REG_EDX & ~regflags))
return R_EDX;
if (!(REG_CL & ~regflags))
return R_CL;
if (!(REG_CX & ~regflags))
return R_CX;
if (!(REG_ECX & ~regflags))
return R_ECX;
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 ? sreg[regval] : 0);
if (!(REG_FSGS & ~regflags))
return (regval == 4 || regval == 5 ? sreg[regval] : 0);
if (!(REG_SEG67 & ~regflags))
return (regval == 6 || regval == 7 ? sreg[regval] : 0);
/* All the entries below look up regval in an 8-entry array */
if (regval < 0 || regval > 7)
return 0;
if (!((REGMEM|BITS8) & ~regflags))
return reg8[regval];
if (!((REGMEM|BITS16) & ~regflags))
return reg16[regval];
if (!((REGMEM|BITS32) & ~regflags))
return reg32[regval];
if (!(REG_SREG & ~regflags))
return sreg[regval];
if (!(REG_CREG & ~regflags))
return creg[regval];
if (!(REG_DREG & ~regflags))
return dreg[regval];
if (!(REG_TREG & ~regflags))
return treg[regval];
if (!(FPUREG & ~regflags))
return fpureg[regval];
if (!(MMXREG & ~regflags))
return mmxreg[regval];
if (!(XMMREG & ~regflags))
return 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 an effective address (ModRM) specification.
*/
static unsigned char *do_ea (unsigned char *data, int modrm, int asize,
int segsize, operand *op)
{
int mod, rm, scale, index, base;
mod = (modrm >> 6) & 03;
rm = modrm & 07;
if (mod == 3) { /* pure register version */
op->basereg = rm;
op->segment |= SEG_RMREG;
return data;
}
op->addr_size = 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 = (signed char) *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*). However, rm=4
* indicates not a single base register, but instead the
* presence of a SIB byte...
*/
op->indexreg = -1;
switch (rm) {
case 0: op->basereg = R_EAX; break;
case 1: op->basereg = R_ECX; break;
case 2: op->basereg = R_EDX; break;
case 3: op->basereg = R_EBX; break;
case 5: op->basereg = R_EBP; break;
case 6: op->basereg = R_ESI; break;
case 7: op->basereg = R_EDI; break;
}
if (rm == 5 && mod == 0) {
op->basereg = -1;
if (segsize != 32)
op->addr_size = 32;
mod = 2; /* fake disp32 */
}
if (rm == 4) { /* process SIB */
scale = (*data >> 6) & 03;
index = (*data >> 3) & 07;
base = *data & 07;
data++;
op->scale = 1 << scale;
switch (index) {
case 0: op->indexreg = R_EAX; break;
case 1: op->indexreg = R_ECX; break;
case 2: op->indexreg = R_EDX; break;
case 3: op->indexreg = R_EBX; break;
case 4: op->indexreg = -1; break;
case 5: op->indexreg = R_EBP; break;
case 6: op->indexreg = R_ESI; break;
case 7: op->indexreg = R_EDI; break;
}
switch (base) {
case 0: op->basereg = R_EAX; break;
case 1: op->basereg = R_ECX; break;
case 2: op->basereg = R_EDX; break;
case 3: op->basereg = R_EBX; break;
case 4: op->basereg = R_ESP; break;
case 6: op->basereg = R_ESI; break;
case 7: op->basereg = R_EDI; break;
case 5:
if (mod == 0) {
mod = 2;
op->basereg = -1;
} else
op->basereg = R_EBP;
break;
}
}
switch (mod) {
case 0:
op->segment |= SEG_NODISP;
break;
case 1:
op->segment |= SEG_DISP8;
op->offset = (signed char) *data++;
break;
case 2:
op->segment |= SEG_DISP32;
op->offset = *data++;
op->offset |= ((unsigned) *data++) << 8;
op->offset |= ((long) *data++) << 16;
op->offset |= ((long) *data++) << 24;
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 (struct itemplate *t, unsigned char *data, int asize,
int osize, int segsize, int rep, insn *ins)
{
unsigned char * r = (unsigned char *)(t->code);
unsigned char * origdata = data;
int a_used = FALSE, o_used = FALSE;
int drep = 0;
if ( rep == 0xF2 )
drep = P_REPNE;
else if ( rep == 0xF3 )
drep = P_REP;
while (*r)
{
int c = *r++;
if (c >= 01 && c <= 03) {
while (c--)
if (*r++ != *data++)
return FALSE;
}
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;
}
}
if (c == 05) {
switch (*data++) {
case 0xA1: ins->oprs[0].basereg = 4; break;
case 0xA9: ins->oprs[0].basereg = 5; break;
default: return FALSE;
}
}
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;
}
}
if (c == 07) {
switch (*data++) {
case 0xA0: ins->oprs[0].basereg = 4; break;
case 0xA8: ins->oprs[0].basereg = 5; break;
default: return FALSE;
}
}
if (c >= 010 && c <= 012) {
int t = *r++, d = *data++;
if (d < t || d > t+7)
return FALSE;
else {
ins->oprs[c-010].basereg = d-t;
ins->oprs[c-010].segment |= SEG_RMREG;
}
}
if (c == 017)
if (*data++)
return FALSE;
if (c >= 014 && c <= 016) {
ins->oprs[c-014].offset = (signed char) *data++;
ins->oprs[c-014].segment |= SEG_SIGNED;
}
if (c >= 020 && c <= 022)
ins->oprs[c-020].offset = *data++;
if (c >= 024 && c <= 026)
ins->oprs[c-024].offset = *data++;
if (c >= 030 && c <= 032) {
ins->oprs[c-030].offset = *data++;
ins->oprs[c-030].offset |= (((unsigned) *data++) << 8);
}
if (c >= 034 && c <= 036) {
ins->oprs[c-034].offset = *data++;
ins->oprs[c-034].offset |= (((unsigned) *data++) << 8);
if (osize == 32) {
ins->oprs[c-034].offset |= (((long) *data++) << 16);
ins->oprs[c-034].offset |= (((long) *data++) << 24);
}
if (segsize != asize)
ins->oprs[c-034].addr_size = asize;
}
if (c >= 040 && c <= 042) {
ins->oprs[c-040].offset = *data++;
ins->oprs[c-040].offset |= (((unsigned) *data++) << 8);
ins->oprs[c-040].offset |= (((long) *data++) << 16);
ins->oprs[c-040].offset |= (((long) *data++) << 24);
}
if (c >= 044 && c <= 046) {
ins->oprs[c-044].offset = *data++;
ins->oprs[c-044].offset |= (((unsigned) *data++) << 8);
if (asize == 32) {
ins->oprs[c-044].offset |= (((long) *data++) << 16);
ins->oprs[c-044].offset |= (((long) *data++) << 24);
}
if (segsize != asize)
ins->oprs[c-044].addr_size = asize;
}
if (c >= 050 && c <= 052) {
ins->oprs[c-050].offset = (signed char) *data++;
ins->oprs[c-050].segment |= SEG_RELATIVE;
}
if (c >= 060 && c <= 062) {
ins->oprs[c-060].offset = *data++;
ins->oprs[c-060].offset |= (((unsigned) *data++) << 8);
ins->oprs[c-060].segment |= SEG_RELATIVE;
ins->oprs[c-060].segment &= ~SEG_32BIT;
}
if (c >= 064 && c <= 066) {
ins->oprs[c-064].offset = *data++;
ins->oprs[c-064].offset |= (((unsigned) *data++) << 8);
if (osize == 32) {
ins->oprs[c-064].offset |= (((long) *data++) << 16);
ins->oprs[c-064].offset |= (((long) *data++) << 24);
ins->oprs[c-064].segment |= SEG_32BIT;
} else
ins->oprs[c-064].segment &= ~SEG_32BIT;
ins->oprs[c-064].segment |= SEG_RELATIVE;
if (segsize != osize) {
ins->oprs[c-064].type =
(ins->oprs[c-064].type & NON_SIZE)
| ((osize == 16) ? BITS16 : BITS32);
}
}
if (c >= 070 && c <= 072) {
ins->oprs[c-070].offset = *data++;
ins->oprs[c-070].offset |= (((unsigned) *data++) << 8);
ins->oprs[c-070].offset |= (((long) *data++) << 16);
ins->oprs[c-070].offset |= (((long) *data++) << 24);
ins->oprs[c-070].segment |= SEG_32BIT | SEG_RELATIVE;
}
if (c >= 0100 && c < 0130) {
int modrm = *data++;
ins->oprs[c & 07].basereg = (modrm >> 3) & 07;
ins->oprs[c & 07].segment |= SEG_RMREG;
data = do_ea (data, modrm, asize, segsize,
&ins->oprs[(c >> 3) & 07]);
}
if (c >= 0130 && c <= 0132) {
ins->oprs[c-0130].offset = *data++;
ins->oprs[c-0130].offset |= (((unsigned) *data++) << 8);
}
if (c >= 0140 && c <= 0142) {
ins->oprs[c-0140].offset = *data++;
ins->oprs[c-0140].offset |= (((unsigned) *data++) << 8);
ins->oprs[c-0140].offset |= (((long) *data++) << 16);
ins->oprs[c-0140].offset |= (((long) *data++) << 24);
}
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]);
}
if (c >= 0300 && c <= 0302) {
if (asize)
ins->oprs[c-0300].segment |= SEG_32BIT;
else
ins->oprs[c-0300].segment &= ~SEG_32BIT;
a_used = TRUE;
}
if (c == 0310) {
if (asize == 32)
return FALSE;
else
a_used = TRUE;
}
if (c == 0311) {
if (asize == 16)
return FALSE;
else
a_used = TRUE;
}
if (c == 0312) {
if (asize != segsize)
return FALSE;
else
a_used = TRUE;
}
if (c == 0320) {
if (osize == 32)
return FALSE;
else
o_used = TRUE;
}
if (c == 0321) {
if (osize == 16)
return FALSE;
else
o_used = TRUE;
}
if (c == 0322) {
if (osize != segsize)
return FALSE;
else
o_used = TRUE;
}
if (c == 0330) {
int t = *r++, d = *data++;
if (d < t || d > t+15)
return FALSE;
else
ins->condition = d - t;
}
if (c == 0331) {
if ( rep )
return FALSE;
}
if (c == 0332) {
if (drep == P_REP)
drep = P_REPE;
}
if (c == 0333) {
if ( rep != 0xF3 )
return FALSE;
drep = 0;
}
}
/*
* Check for unused rep or a/o prefixes.
*/
ins->nprefix = 0;
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)
ins->prefixes[ins->nprefix++] = (osize == 16 ? P_O16 : P_O32);
return data - origdata;
}
long disasm (unsigned char *data, char *output, int segsize, long offset)
{
struct itemplate **p, **best_p;
int length, best_length = 0;
const char *segover;
int rep, lock, asize, osize, i, slen, colon;
unsigned char *origdata;
int works;
insn tmp_ins = { NULL }, ins;
unsigned long goodness, best;
/*
* Scan for prefixes.
*/
asize = osize = segsize;
segover = NULL;
ins.condition = ins.nprefix = rep = lock = 0;
origdata = data;
for (;;) {
if (*data == 0xF3 || *data == 0xF2)
rep = *data++;
else if (*data == 0xF0)
lock = *data++;
else if (*data == 0x2E || *data == 0x36 || *data == 0x3E ||
*data == 0x26 || *data == 0x64 || *data == 0x65) {
switch (*data++) {
case 0x2E: segover = "cs"; break;
case 0x36: segover = "ss"; break;
case 0x3E: segover = "ds"; break;
case 0x26: segover = "es"; break;
case 0x64: segover = "fs"; break;
case 0x65: segover = "gs"; break;
}
} else if (*data == 0x66)
osize = 48 - segsize, data++;
else if (*data == 0x67)
asize = 48 - segsize, data++;
else
break;
}
tmp_ins.oprs[0].segment = tmp_ins.oprs[1].segment =
tmp_ins.oprs[2].segment =
tmp_ins.oprs[0].addr_size = tmp_ins.oprs[1].addr_size =
tmp_ins.oprs[2].addr_size = (segsize == 16 ? 0 : SEG_32BIT);
tmp_ins.condition = -1;
best = ~0UL; /* Worst possible */
best_p = NULL;
for (p = itable[*data]; *p; p++) {
if ( (length = matches(*p, data, asize, osize,
segsize, rep, &tmp_ins)) ) {
works = TRUE;
/*
* Final check to make sure the types of r/m match up.
*/
for (i = 0; i < (*p)->operands; i++) {
if (
/* 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) &&
!(REGNORM & ~(*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))) {
works = FALSE;
break;
}
}
if (works) {
goodness = (*p)->flags & IF_PFMASK;
if ( goodness < best ) {
/* This is the best one found so far */
best = goodness;
best_p = p;
best_length = length;
ins = tmp_ins;
}
}
}
}
if (!best_p) { /* no instruction was matched */
sprintf(output, "db 0%02xh", data[0]);
return 1;
}
/* Pick the best match */
p = best_p;
length = best_length;
slen = 0;
if (lock)
slen += sprintf(output+slen, "lock ");
for (i = 0; i < ins.nprefix; i++)
switch (ins.prefixes[i]) {
case P_REP: slen += sprintf(output+slen, "rep "); break;
case P_REPE: slen += sprintf(output+slen, "repe "); break;
case P_REPNE: slen += sprintf(output+slen, "repne "); break;
case P_A16: slen += sprintf(output+slen, "a16 "); break;
case P_A32: slen += sprintf(output+slen, "a32 "); break;
case P_O16: slen += sprintf(output+slen, "o16 "); break;
case P_O32: slen += sprintf(output+slen, "o32 "); break;
}
for (i = 0; i < (int)elements(ico); i++)
if ((*p)->opcode == ico[i]) {
slen += sprintf(output+slen, "%s%s", icn[i],
whichcond(ins.condition));
break;
}
if (i >= (int)elements(ico))
slen += sprintf(output+slen, "%s", insn_names[(*p)->opcode]);
colon = FALSE;
length += data - origdata; /* fix up for prefixes */
for (i=0; i<(*p)->operands; i++) {
output[slen++] = (colon ? ':' : i==0 ? ' ' : ',');
if (ins.oprs[i].segment & SEG_RELATIVE) {
ins.oprs[i].offset += offset + length;
/*
* sort out wraparound
*/
if (!(ins.oprs[i].segment & SEG_32BIT))
ins.oprs[i].offset &= 0xFFFF;
}
if ((*p)->opd[i] & COLON)
colon = TRUE;
else
colon = FALSE;
if (((*p)->opd[i] & (REGISTER | FPUREG)) ||
(ins.oprs[i].segment & SEG_RMREG))
{
ins.oprs[i].basereg = whichreg ((*p)->opd[i],
ins.oprs[i].basereg);
if ( (*p)->opd[i] & TO )
slen += sprintf(output+slen, "to ");
slen += sprintf(output+slen, "%s",
reg_names[ins.oprs[i].basereg-EXPR_REG_START]);
} else if (!(UNITY & ~(*p)->opd[i])) {
output[slen++] = '1';
} else if ( (*p)->opd[i] & IMMEDIATE ) {
if ( (*p)->opd[i] & BITS8 ) {
slen += sprintf(output+slen, "byte ");
if (ins.oprs[i].segment & SEG_SIGNED) {
if (ins.oprs[i].offset < 0) {
ins.oprs[i].offset *= -1;
output[slen++] = '-';
} else
output[slen++] = '+';
}
} else if ( (*p)->opd[i] & BITS16 ) {
slen += sprintf(output+slen, "word ");
} else if ( (*p)->opd[i] & BITS32 ) {
slen += sprintf(output+slen, "dword ");
} else if ( (*p)->opd[i] & NEAR ) {
slen += sprintf(output+slen, "near ");
} else if ( (*p)->opd[i] & SHORT ) {
slen += sprintf(output+slen, "short ");
}
slen += sprintf(output+slen, "0x%lx", ins.oprs[i].offset);
} else if ( !(MEM_OFFS & ~(*p)->opd[i]) ) {
slen += sprintf(output+slen, "[%s%s%s0x%lx]",
(segover ? segover : ""),
(segover ? ":" : ""),
(ins.oprs[i].addr_size == 32 ? "dword " :
ins.oprs[i].addr_size == 16 ? "word " : ""),
ins.oprs[i].offset);
segover = NULL;
} else if ( !(REGMEM & ~(*p)->opd[i]) ) {
int started = FALSE;
if ( (*p)->opd[i] & BITS8 )
slen += sprintf(output+slen, "byte ");
if ( (*p)->opd[i] & BITS16 )
slen += sprintf(output+slen, "word ");
if ( (*p)->opd[i] & BITS32 )
slen += sprintf(output+slen, "dword ");
if ( (*p)->opd[i] & BITS64 )
slen += sprintf(output+slen, "qword ");
if ( (*p)->opd[i] & BITS80 )
slen += sprintf(output+slen, "tword ");
if ( (*p)->opd[i] & FAR )
slen += sprintf(output+slen, "far ");
if ( (*p)->opd[i] & NEAR )
slen += sprintf(output+slen, "near ");
output[slen++] = '[';
if (ins.oprs[i].addr_size)
slen += sprintf(output+slen, "%s",
(ins.oprs[i].addr_size == 32 ? "dword " :
ins.oprs[i].addr_size == 16 ? "word " : ""));
if (segover) {
slen += sprintf(output+slen, "%s:", segover);
segover = NULL;
}
if (ins.oprs[i].basereg != -1) {
slen += sprintf(output+slen, "%s",
reg_names[(ins.oprs[i].basereg -
EXPR_REG_START)]);
started = TRUE;
}
if (ins.oprs[i].indexreg != -1) {
if (started)
output[slen++] = '+';
slen += sprintf(output+slen, "%s",
reg_names[(ins.oprs[i].indexreg -
EXPR_REG_START)]);
if (ins.oprs[i].scale > 1)
slen += sprintf(output+slen, "*%d", ins.oprs[i].scale);
started = TRUE;
}
if (ins.oprs[i].segment & SEG_DISP8) {
int sign = '+';
if (ins.oprs[i].offset & 0x80) {
ins.oprs[i].offset = - (signed char) ins.oprs[i].offset;
sign = '-';
}
slen += sprintf(output+slen, "%c0x%lx", sign,
ins.oprs[i].offset);
} else if (ins.oprs[i].segment & SEG_DISP16) {
if (started)
output[slen++] = '+';
slen += sprintf(output+slen, "0x%lx", ins.oprs[i].offset);
} else if (ins.oprs[i].segment & SEG_DISP32) {
if (started)
output[slen++] = '+';
slen += sprintf(output+slen, "0x%lx", ins.oprs[i].offset);
}
output[slen++] = ']';
} else {
slen += sprintf(output+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;
}