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https://github.com/netwide-assembler/nasm.git
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dbf130e681
Rename REGNORM to REG_EA to make the distinction between REG_GPR and REG_EA clearer.
929 lines
29 KiB
C
929 lines
29 KiB
C
/* disasm.c where all the _work_ gets done in the Netwide Disassembler
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*
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* The Netwide Assembler is copyright (C) 1996 Simon Tatham and
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* Julian Hall. All rights reserved. The software is
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* redistributable under the licence given in the file "Licence"
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* distributed in the NASM archive.
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*
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* initial version 27/iii/95 by Simon Tatham
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*/
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#include <stdio.h>
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#include <string.h>
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#include <inttypes.h>
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#include "nasm.h"
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#include "disasm.h"
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#include "sync.h"
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#include "insns.h"
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#include "names.c"
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extern struct itemplate **itable[];
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/*
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* Flags that go into the `segment' field of `insn' structures
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* during disassembly.
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*/
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#define SEG_RELATIVE 1
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#define SEG_32BIT 2
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#define SEG_RMREG 4
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#define SEG_DISP8 8
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#define SEG_DISP16 16
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#define SEG_DISP32 32
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#define SEG_NODISP 64
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#define SEG_SIGNED 128
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#define SEG_64BIT 256
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/*
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* REX flags
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*/
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#define REX_P 0x40 /* REX prefix present */
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#define REX_W 0x08 /* 64-bit operand size */
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#define REX_R 0x04 /* ModRM reg extension */
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#define REX_X 0x02 /* SIB index extension */
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#define REX_B 0x01 /* ModRM r/m extension */
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#include "regdis.c"
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#define getu8(x) (*(uint8_t *)(x))
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#if defined(__i386__) || defined(__x86_64__)
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/* Littleendian CPU which can handle unaligned references */
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#define getu16(x) (*(uint16_t *)(x))
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#define getu32(x) (*(uint32_t *)(x))
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#define getu64(x) (*(uint64_t *)(x))
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#else
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static uint16_t getu16(uint8_t *data)
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{
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return (uint16_t)data[0] + ((uint16_t)data[1] << 8);
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}
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static uint32_t getu32(uint8_t *data)
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{
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return (uint32_t)getu16(data) + ((uint32_t)getu16(data+2) << 16);
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}
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static uint64_t getu64(uint8_t *data)
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{
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return (uint64_t)getu32(data) + ((uint64_t)getu32(data+4) << 32);
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}
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#endif
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#define gets8(x) ((int8_t)getu8(x))
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#define gets16(x) ((int16_t)getu16(x))
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#define gets32(x) ((int32_t)getu32(x))
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#define gets64(x) ((int64_t)getu64(x))
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/* Important: regval must already have been adjusted for rex extensions */
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static int whichreg(int32_t regflags, int regval, int rex)
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{
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if (!(REG_AL & ~regflags))
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return R_AL;
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if (!(REG_AX & ~regflags))
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return R_AX;
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if (!(REG_EAX & ~regflags))
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return R_EAX;
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if (!(REG_RAX & ~regflags))
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return R_RAX;
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if (!(REG_DL & ~regflags))
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return R_DL;
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if (!(REG_DX & ~regflags))
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return R_DX;
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if (!(REG_EDX & ~regflags))
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return R_EDX;
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if (!(REG_RDX & ~regflags))
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return R_RDX;
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if (!(REG_CL & ~regflags))
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return R_CL;
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if (!(REG_CX & ~regflags))
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return R_CX;
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if (!(REG_ECX & ~regflags))
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return R_ECX;
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if (!(REG_RCX & ~regflags))
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return R_RCX;
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if (!(FPU0 & ~regflags))
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return R_ST0;
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if (!(REG_CS & ~regflags))
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return (regval == 1) ? R_CS : 0;
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if (!(REG_DESS & ~regflags))
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return (regval == 0 || regval == 2
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|| regval == 3 ? rd_sreg[regval] : 0);
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if (!(REG_FSGS & ~regflags))
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return (regval == 4 || regval == 5 ? rd_sreg[regval] : 0);
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if (!(REG_SEG67 & ~regflags))
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return (regval == 6 || regval == 7 ? rd_sreg[regval] : 0);
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/* All the entries below look up regval in an 16-entry array */
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if (regval < 0 || regval > 15)
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return 0;
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if (!((REGMEM | BITS8) & ~regflags)) {
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if (rex & REX_P)
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return rd_reg8_rex[regval];
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else
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return rd_reg8[regval];
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}
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if (!((REGMEM | BITS16) & ~regflags))
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return rd_reg16[regval];
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if (!((REGMEM | BITS32) & ~regflags))
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return rd_reg32[regval];
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if (!((REGMEM | BITS64) & ~regflags))
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return rd_reg64[regval];
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if (!(REG_SREG & ~regflags))
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return rd_sreg[regval & 7]; /* Ignore REX */
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if (!(REG_CREG & ~regflags))
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return rd_creg[regval];
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if (!(REG_DREG & ~regflags))
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return rd_dreg[regval];
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if (!(REG_TREG & ~regflags)) {
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if (rex & REX_P)
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return 0; /* TR registers are ill-defined with rex */
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return rd_treg[regval];
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}
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if (!(FPUREG & ~regflags))
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return rd_fpureg[regval & 7]; /* Ignore REX */
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if (!(MMXREG & ~regflags))
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return rd_mmxreg[regval & 7]; /* Ignore REX */
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if (!(XMMREG & ~regflags))
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return rd_xmmreg[regval];
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return 0;
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}
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static const char *whichcond(int condval)
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{
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static int conds[] = {
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C_O, C_NO, C_C, C_NC, C_Z, C_NZ, C_NA, C_A,
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C_S, C_NS, C_PE, C_PO, C_L, C_NL, C_NG, C_G
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};
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return conditions[conds[condval]];
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}
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/*
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* Process an effective address (ModRM) specification.
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*/
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static uint8_t *do_ea(uint8_t *data, int modrm, int asize,
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int segsize, operand * op, int rex)
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{
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int mod, rm, scale, index, base;
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mod = (modrm >> 6) & 03;
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rm = modrm & 07;
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if (mod == 3) { /* pure register version */
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op->basereg = rm+(rex & REX_B ? 8 : 0);
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op->segment |= SEG_RMREG;
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return data;
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}
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op->addr_size = 0;
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if (asize == 16) {
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/*
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* <mod> specifies the displacement size (none, byte or
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* word), and <rm> specifies the register combination.
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* Exception: mod=0,rm=6 does not specify [BP] as one might
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* expect, but instead specifies [disp16].
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*/
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op->indexreg = op->basereg = -1;
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op->scale = 1; /* always, in 16 bits */
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switch (rm) {
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case 0:
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op->basereg = R_BX;
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op->indexreg = R_SI;
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break;
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case 1:
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op->basereg = R_BX;
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op->indexreg = R_DI;
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break;
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case 2:
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op->basereg = R_BP;
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op->indexreg = R_SI;
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break;
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case 3:
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op->basereg = R_BP;
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op->indexreg = R_DI;
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break;
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case 4:
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op->basereg = R_SI;
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break;
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case 5:
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op->basereg = R_DI;
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break;
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case 6:
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op->basereg = R_BP;
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break;
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case 7:
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op->basereg = R_BX;
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break;
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}
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if (rm == 6 && mod == 0) { /* special case */
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op->basereg = -1;
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if (segsize != 16)
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op->addr_size = 16;
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mod = 2; /* fake disp16 */
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}
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switch (mod) {
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case 0:
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op->segment |= SEG_NODISP;
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break;
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case 1:
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op->segment |= SEG_DISP8;
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op->offset = (int8_t)*data++;
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break;
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case 2:
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op->segment |= SEG_DISP16;
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op->offset = *data++;
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op->offset |= ((unsigned)*data++) << 8;
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break;
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}
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return data;
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} else {
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/*
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* Once again, <mod> specifies displacement size (this time
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* none, byte or *dword*), while <rm> specifies the base
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* register. Again, [EBP] is missing, replaced by a pure
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* disp32 (this time that's mod=0,rm=*5*) in 32-bit mode,
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* and RIP-relative addressing in 64-bit mode.
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*
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* However, rm=4
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* indicates not a single base register, but instead the
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* presence of a SIB byte...
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*/
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int a64 = asize == 64;
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op->indexreg = -1;
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if (a64)
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op->basereg = rd_reg64[rm | ((rex & REX_B) ? 8 : 0)];
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else
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op->basereg = rd_reg32[rm | ((rex & REX_B) ? 8 : 0)];
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if (rm == 5 && mod == 0) {
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if (segsize == 64) {
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op->basereg = R_RIP;
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op->segment |= SEG_RELATIVE;
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mod = 2; /* fake disp32 */
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} else {
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op->basereg = -1;
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if (segsize != 32)
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op->addr_size = 32;
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mod = 2; /* fake disp32 */
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}
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}
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if (rm == 4) { /* process SIB */
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scale = (*data >> 6) & 03;
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index = (*data >> 3) & 07;
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base = *data & 07;
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data++;
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op->scale = 1 << scale;
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if (index == 4)
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op->indexreg = -1; /* ESP/RSP/R12 cannot be an index */
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else if (a64)
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op->indexreg = rd_reg64[index | ((rex & REX_X) ? 8 : 0)];
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else
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op->indexreg = rd_reg64[index | ((rex & REX_X) ? 8 : 0)];
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if (base == 5 && mod == 0) {
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op->basereg = -1;
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mod = 2; /* Fake disp32 */
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} else if (a64)
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op->basereg = rd_reg64[base | ((rex & REX_B) ? 8 : 0)];
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else
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op->basereg = rd_reg32[base | ((rex & REX_B) ? 8 : 0)];
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}
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switch (mod) {
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case 0:
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op->segment |= SEG_NODISP;
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break;
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case 1:
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op->segment |= SEG_DISP8;
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op->offset = gets8(data);
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data++;
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break;
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case 2:
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op->segment |= SEG_DISP32;
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op->offset = getu32(data);
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data += 4;
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break;
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}
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return data;
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}
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}
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/*
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* Determine whether the instruction template in t corresponds to the data
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* stream in data. Return the number of bytes matched if so.
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*/
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static int matches(struct itemplate *t, uint8_t *data, int asize,
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int osize, int segsize, int rep, insn * ins,
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int rex, int *rexout, int lock)
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{
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uint8_t *r = (uint8_t *)(t->code);
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uint8_t *origdata = data;
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int a_used = FALSE, o_used = FALSE;
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int drep = 0;
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*rexout = rex;
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if (t->flags & (segsize == 64 ? IF_NOLONG : IF_LONG))
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return FALSE;
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if (rep == 0xF2)
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drep = P_REPNE;
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else if (rep == 0xF3)
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drep = P_REP;
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while (*r) {
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int c = *r++;
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/* FIX: change this into a switch */
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if (c >= 01 && c <= 03) {
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while (c--)
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if (*r++ != *data++)
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return FALSE;
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} else if (c == 04) {
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switch (*data++) {
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case 0x07:
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ins->oprs[0].basereg = 0;
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break;
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case 0x17:
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ins->oprs[0].basereg = 2;
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break;
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case 0x1F:
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ins->oprs[0].basereg = 3;
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break;
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default:
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return FALSE;
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}
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} else if (c == 05) {
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switch (*data++) {
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case 0xA1:
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ins->oprs[0].basereg = 4;
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break;
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case 0xA9:
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ins->oprs[0].basereg = 5;
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break;
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default:
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return FALSE;
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}
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} else if (c == 06) {
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switch (*data++) {
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case 0x06:
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ins->oprs[0].basereg = 0;
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break;
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case 0x0E:
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ins->oprs[0].basereg = 1;
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break;
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case 0x16:
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ins->oprs[0].basereg = 2;
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break;
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case 0x1E:
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ins->oprs[0].basereg = 3;
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break;
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default:
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return FALSE;
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}
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} else if (c == 07) {
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switch (*data++) {
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case 0xA0:
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ins->oprs[0].basereg = 4;
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break;
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case 0xA8:
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ins->oprs[0].basereg = 5;
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break;
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default:
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return FALSE;
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}
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} else if (c >= 010 && c <= 012) {
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int t = *r++, d = *data++;
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if (d < t || d > t + 7)
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return FALSE;
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else {
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ins->oprs[c - 010].basereg = (d-t)+(rex & REX_B ? 8 : 0);
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ins->oprs[c - 010].segment |= SEG_RMREG;
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}
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} else if (c == 017) {
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if (*data++)
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return FALSE;
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} else if (c >= 014 && c <= 016) {
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ins->oprs[c - 014].offset = (int8_t)*data++;
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ins->oprs[c - 014].segment |= SEG_SIGNED;
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} else if (c >= 020 && c <= 022) {
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ins->oprs[c - 020].offset = *data++;
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} else if (c >= 024 && c <= 026) {
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ins->oprs[c - 024].offset = *data++;
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} else if (c >= 030 && c <= 032) {
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ins->oprs[c - 030].offset = getu16(data);
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data += 2;
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} else if (c >= 034 && c <= 036) {
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if (osize == 32) {
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ins->oprs[c - 034].offset = getu32(data);
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data += 4;
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} else {
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ins->oprs[c - 034].offset = getu16(data);
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data += 2;
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}
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if (segsize != asize)
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ins->oprs[c - 034].addr_size = asize;
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} else if (c >= 040 && c <= 042) {
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ins->oprs[c - 040].offset = getu32(data);
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data += 4;
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} else if (c >= 044 && c <= 046) {
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switch (asize) {
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case 16:
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ins->oprs[c - 044].offset = getu16(data);
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data += 2;
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break;
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case 32:
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ins->oprs[c - 044].offset = getu32(data);
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data += 4;
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break;
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case 64:
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ins->oprs[c - 044].offset = getu64(data);
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data += 8;
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break;
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}
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if (segsize != asize)
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ins->oprs[c - 044].addr_size = asize;
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} else if (c >= 050 && c <= 052) {
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ins->oprs[c - 050].offset = gets8(data++);
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ins->oprs[c - 050].segment |= SEG_RELATIVE;
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} else if (c >= 054 && c <= 056) {
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ins->oprs[c - 054].offset = getu64(data);
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data += 8;
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} else if (c >= 060 && c <= 062) {
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ins->oprs[c - 060].offset = gets16(data);
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data += 2;
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ins->oprs[c - 060].segment |= SEG_RELATIVE;
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ins->oprs[c - 060].segment &= ~SEG_32BIT;
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} else if (c >= 064 && c <= 066) {
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if (osize == 16) {
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ins->oprs[c - 064].offset = getu16(data);
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data += 2;
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ins->oprs[c - 064].segment &= ~(SEG_32BIT|SEG_64BIT);
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} else if (osize == 32) {
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ins->oprs[c - 064].offset = getu32(data);
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data += 4;
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ins->oprs[c - 064].segment &= ~SEG_64BIT;
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ins->oprs[c - 064].segment |= SEG_32BIT;
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}
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if (segsize != osize) {
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ins->oprs[c - 064].type =
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(ins->oprs[c - 064].type & ~SIZE_MASK)
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| ((osize == 16) ? BITS16 : BITS32);
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}
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} else if (c >= 070 && c <= 072) {
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ins->oprs[c - 070].offset = getu32(data);
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data += 4;
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ins->oprs[c - 070].segment |= SEG_32BIT | SEG_RELATIVE;
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} else if (c >= 0100 && c < 0130) {
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int modrm = *data++;
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ins->oprs[c & 07].basereg = ((modrm >> 3)&7)+(rex & REX_R ? 8 : 0);
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ins->oprs[c & 07].segment |= SEG_RMREG;
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data = do_ea(data, modrm, asize, segsize,
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&ins->oprs[(c >> 3) & 07], rex);
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} else if (c >= 0130 && c <= 0132) {
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ins->oprs[c - 0130].offset = getu16(data);
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data += 2;
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} else if (c >= 0140 && c <= 0142) {
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ins->oprs[c - 0140].offset = getu32(data);
|
|
data += 4;
|
|
} 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], rex);
|
|
} else if (c >= 0300 && c <= 0302) {
|
|
a_used = TRUE;
|
|
} 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 == 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) {
|
|
rex |= REX_W; /* 64-bit only instruction */
|
|
osize = 64;
|
|
} else if (c == 0324) {
|
|
if (!(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 (rep)
|
|
return FALSE;
|
|
} else if (c == 0332) {
|
|
if (drep == P_REP)
|
|
drep = P_REPE;
|
|
} else if (c == 0333) {
|
|
if (rep != 0xF3)
|
|
return FALSE;
|
|
drep = 0;
|
|
} else if (c == 0334) {
|
|
if (lock) {
|
|
rex |= REX_R;
|
|
lock = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check for unused rep or a/o prefixes.
|
|
*/
|
|
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 */
|
|
|
|
*rexout = rex;
|
|
return data - origdata;
|
|
}
|
|
|
|
int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize,
|
|
int32_t offset, int autosync, uint32_t prefer)
|
|
{
|
|
struct itemplate **p, **best_p;
|
|
int length, best_length = 0;
|
|
char *segover;
|
|
int rep, lock, asize, osize, i, slen, colon, rex, rexout, best_rex;
|
|
uint8_t *origdata;
|
|
int works;
|
|
insn tmp_ins, ins;
|
|
uint32_t goodness, best;
|
|
|
|
/*
|
|
* Scan for prefixes.
|
|
*/
|
|
asize = segsize;
|
|
osize = (segsize == 64) ? 32 : segsize;
|
|
rex = 0;
|
|
segover = NULL;
|
|
rep = lock = 0;
|
|
origdata = data;
|
|
for (;;) {
|
|
if (*data == 0xF3 || *data == 0xF2)
|
|
rep = *data++;
|
|
else if (*data == 0xF0)
|
|
lock = *data++;
|
|
else if (*data == 0x2E)
|
|
segover = "cs", data++;
|
|
else if (*data == 0x36)
|
|
segover = "ss", data++;
|
|
else if (*data == 0x3E)
|
|
segover = "ds", data++;
|
|
else if (*data == 0x26)
|
|
segover = "es", data++;
|
|
else if (*data == 0x64)
|
|
segover = "fs", data++;
|
|
else if (*data == 0x65)
|
|
segover = "gs", data++;
|
|
else if (*data == 0x66) {
|
|
osize = (segsize == 16) ? 32 : 16;
|
|
data++;
|
|
} else if (*data == 0x67) {
|
|
asize = (segsize == 32) ? 16 : 32;
|
|
data++;
|
|
} else if (segsize == 64 && (*data & 0xf0) == REX_P) {
|
|
rex = *data++;
|
|
if (rex & REX_W)
|
|
osize = 64;
|
|
break; /* REX is always the last prefix */
|
|
} 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 == 64 ? SEG_64BIT :
|
|
segsize == 32 ? SEG_32BIT : 0);
|
|
tmp_ins.condition = -1;
|
|
best = -1; /* Worst possible */
|
|
best_p = NULL;
|
|
best_rex = 0;
|
|
for (p = itable[*data]; *p; p++) {
|
|
if ((length = matches(*p, data, asize, osize, segsize, rep,
|
|
&tmp_ins, rex, &rexout, lock))) {
|
|
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 (
|
|
/* 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, rexout))) {
|
|
works = FALSE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (works) {
|
|
goodness = ((*p)->flags & IF_PFMASK) ^ prefer;
|
|
if (goodness < best) {
|
|
/* This is the best one found so far */
|
|
best = goodness;
|
|
best_p = p;
|
|
best_length = length;
|
|
ins = tmp_ins;
|
|
best_rex = rexout;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!best_p)
|
|
return 0; /* no instruction was matched */
|
|
|
|
/* Pick the best match */
|
|
p = best_p;
|
|
length = best_length;
|
|
rex = best_rex;
|
|
if (best_rex & REX_W)
|
|
osize = 64;
|
|
|
|
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;
|
|
}
|
|
|
|
for (i = 0; i < elements(ico); i++)
|
|
if ((*p)->opcode == ico[i]) {
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "%s%s", icn[i],
|
|
whichcond(ins.condition));
|
|
break;
|
|
}
|
|
if (i >= 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++) {
|
|
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|SEG_64BIT)))
|
|
ins.oprs[i].offset &= 0xffff;
|
|
/*
|
|
* add sync marker, if autosync is on
|
|
*/
|
|
if (autosync)
|
|
add_sync(ins.oprs[i].offset, 0L);
|
|
}
|
|
|
|
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, rex);
|
|
if ((*p)->opd[i] & TO)
|
|
slen += snprintf(output + slen, outbufsize - slen, "to ");
|
|
slen += snprintf(output + slen, outbufsize - 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 +=
|
|
snprintf(output + slen, outbufsize - 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 +=
|
|
snprintf(output + slen, outbufsize - slen, "word ");
|
|
} else if ((*p)->opd[i] & BITS32) {
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "dword ");
|
|
} else if ((*p)->opd[i] & BITS64) {
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "qword ");
|
|
} else if ((*p)->opd[i] & NEAR) {
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "near ");
|
|
} else if ((*p)->opd[i] & SHORT) {
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "short ");
|
|
}
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "0x%"PRIx64"",
|
|
ins.oprs[i].offset);
|
|
} else if (!(MEM_OFFS & ~(*p)->opd[i])) {
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "[%s%s%s0x%"PRIx64"]",
|
|
((const char*)segover ? (const char*)segover : ""), /* placate type mistmatch warning */
|
|
((const char*)segover ? ":" : ""), /* by using (const char*) instead of uint8_t* */
|
|
(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 +=
|
|
snprintf(output + slen, outbufsize - slen, "byte ");
|
|
if ((*p)->opd[i] & BITS16)
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "word ");
|
|
if ((*p)->opd[i] & BITS32)
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "dword ");
|
|
if ((*p)->opd[i] & BITS64)
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "qword ");
|
|
if ((*p)->opd[i] & BITS80)
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "tword ");
|
|
if ((*p)->opd[i] & FAR)
|
|
slen += snprintf(output + slen, outbufsize - slen, "far ");
|
|
if ((*p)->opd[i] & NEAR)
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "near ");
|
|
output[slen++] = '[';
|
|
if (ins.oprs[i].addr_size)
|
|
slen += snprintf(output + slen, outbufsize - slen, "%s",
|
|
(ins.oprs[i].addr_size == 64 ? "qword " :
|
|
ins.oprs[i].addr_size == 32 ? "dword " :
|
|
ins.oprs[i].addr_size == 16 ? "word " :
|
|
""));
|
|
if (segover) {
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "%s:",
|
|
segover);
|
|
segover = NULL;
|
|
}
|
|
if (ins.oprs[i].basereg != -1) {
|
|
slen += snprintf(output + slen, outbufsize - slen, "%s",
|
|
reg_names[(ins.oprs[i].basereg -
|
|
EXPR_REG_START)]);
|
|
started = TRUE;
|
|
}
|
|
if (ins.oprs[i].indexreg != -1) {
|
|
if (started)
|
|
output[slen++] = '+';
|
|
slen += snprintf(output + slen, outbufsize - slen, "%s",
|
|
reg_names[(ins.oprs[i].indexreg -
|
|
EXPR_REG_START)]);
|
|
if (ins.oprs[i].scale > 1)
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "*%d",
|
|
ins.oprs[i].scale);
|
|
started = TRUE;
|
|
}
|
|
if (ins.oprs[i].segment & SEG_DISP8) {
|
|
int minus = 0;
|
|
int8_t offset = ins.oprs[i].offset;
|
|
if (offset < 0) {
|
|
minus = 1;
|
|
offset = -offset;
|
|
}
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx8"",
|
|
minus ? "-" : "+", offset);
|
|
} else if (ins.oprs[i].segment & SEG_DISP16) {
|
|
int minus = 0;
|
|
int16_t offset = ins.oprs[i].offset;
|
|
if (offset < 0) {
|
|
minus = 1;
|
|
offset = -offset;
|
|
}
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx16"",
|
|
minus ? "-" : started ? "+" : "", offset);
|
|
} else if (ins.oprs[i].segment & SEG_DISP32) {
|
|
char *prefix = "";
|
|
int32_t offset = ins.oprs[i].offset;
|
|
if (ins.oprs[i].basereg == R_RIP) {
|
|
prefix = ":";
|
|
} else 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;
|
|
}
|