898 lines
29 KiB
C
898 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 "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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static int whichreg(long regflags, int regval)
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{
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#include "regdis.c"
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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_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_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 (!(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 ? sreg[regval] : 0);
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if (!(REG_FSGS & ~regflags))
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return (regval == 4 || regval == 5 ? sreg[regval] : 0);
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if (!(REG_SEG67 & ~regflags))
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return (regval == 6 || regval == 7 ? sreg[regval] : 0);
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/* All the entries below look up regval in an 8-entry array */
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if (regval < 0 || regval > 7)
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return 0;
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if (!((REGMEM | BITS8) & ~regflags))
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return reg8[regval];
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if (!((REGMEM | BITS16) & ~regflags))
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return reg16[regval];
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if (!((REGMEM | BITS32) & ~regflags))
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return reg32[regval];
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if (!(REG_SREG & ~regflags))
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return sreg[regval];
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if (!(REG_CREG & ~regflags))
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return creg[regval];
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if (!(REG_DREG & ~regflags))
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return dreg[regval];
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if (!(REG_TREG & ~regflags))
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return treg[regval];
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if (!(FPUREG & ~regflags))
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return fpureg[regval];
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if (!(MMXREG & ~regflags))
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return mmxreg[regval];
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if (!(XMMREG & ~regflags))
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return 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 unsigned char *do_ea(unsigned char *data, int modrm, int asize,
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int segsize, operand * op)
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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;
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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 = (signed char)*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*). 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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op->indexreg = -1;
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switch (rm) {
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case 0:
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op->basereg = R_EAX;
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break;
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case 1:
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op->basereg = R_ECX;
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break;
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case 2:
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op->basereg = R_EDX;
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break;
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case 3:
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op->basereg = R_EBX;
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break;
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case 5:
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op->basereg = R_EBP;
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break;
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case 6:
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op->basereg = R_ESI;
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break;
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case 7:
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op->basereg = R_EDI;
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break;
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}
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if (rm == 5 && mod == 0) {
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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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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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switch (index) {
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case 0:
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op->indexreg = R_EAX;
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break;
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case 1:
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op->indexreg = R_ECX;
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break;
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case 2:
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op->indexreg = R_EDX;
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break;
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case 3:
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op->indexreg = R_EBX;
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break;
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case 4:
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op->indexreg = -1;
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break;
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case 5:
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op->indexreg = R_EBP;
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break;
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case 6:
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op->indexreg = R_ESI;
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break;
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case 7:
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op->indexreg = R_EDI;
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break;
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}
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switch (base) {
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case 0:
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op->basereg = R_EAX;
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break;
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case 1:
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op->basereg = R_ECX;
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break;
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case 2:
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op->basereg = R_EDX;
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break;
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case 3:
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op->basereg = R_EBX;
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break;
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case 4:
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op->basereg = R_ESP;
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break;
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case 6:
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op->basereg = R_ESI;
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break;
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case 7:
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op->basereg = R_EDI;
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break;
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case 5:
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if (mod == 0) {
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mod = 2;
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op->basereg = -1;
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} else
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op->basereg = R_EBP;
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break;
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}
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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 = (signed char)*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 = *data++;
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op->offset |= ((unsigned)*data++) << 8;
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op->offset |= ((long)*data++) << 16;
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op->offset |= ((long)*data++) << 24;
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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, unsigned char *data, int asize,
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int osize, int segsize, int rep, insn * ins)
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{
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unsigned char *r = (unsigned char *)(t->code);
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unsigned char *origdata = data;
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int a_used = FALSE, o_used = FALSE;
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int drep = 0;
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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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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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}
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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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}
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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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}
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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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}
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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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}
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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;
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ins->oprs[c - 010].segment |= SEG_RMREG;
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}
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}
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if (c == 017)
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if (*data++)
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return FALSE;
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if (c >= 014 && c <= 016) {
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ins->oprs[c - 014].offset = (signed char)*data++;
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ins->oprs[c - 014].segment |= SEG_SIGNED;
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}
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if (c >= 020 && c <= 022)
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ins->oprs[c - 020].offset = *data++;
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if (c >= 024 && c <= 026)
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ins->oprs[c - 024].offset = *data++;
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if (c >= 030 && c <= 032) {
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ins->oprs[c - 030].offset = *data++;
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ins->oprs[c - 030].offset |= (((unsigned)*data++) << 8);
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}
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if (c >= 034 && c <= 036) {
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ins->oprs[c - 034].offset = *data++;
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ins->oprs[c - 034].offset |= (((unsigned)*data++) << 8);
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if (osize == 32) {
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ins->oprs[c - 034].offset |= (((long)*data++) << 16);
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ins->oprs[c - 034].offset |= (((long)*data++) << 24);
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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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}
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if (c >= 040 && c <= 042) {
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ins->oprs[c - 040].offset = *data++;
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ins->oprs[c - 040].offset |= (((unsigned)*data++) << 8);
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ins->oprs[c - 040].offset |= (((long)*data++) << 16);
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ins->oprs[c - 040].offset |= (((long)*data++) << 24);
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}
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if (c >= 044 && c <= 046) {
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ins->oprs[c - 044].offset = *data++;
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ins->oprs[c - 044].offset |= (((unsigned)*data++) << 8);
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if (asize == 32) {
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ins->oprs[c - 044].offset |= (((long)*data++) << 16);
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ins->oprs[c - 044].offset |= (((long)*data++) << 24);
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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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}
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if (c >= 050 && c <= 052) {
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ins->oprs[c - 050].offset = (signed char)*data++;
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ins->oprs[c - 050].segment |= SEG_RELATIVE;
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}
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if (c >= 060 && c <= 062) {
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ins->oprs[c - 060].offset = *data++;
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ins->oprs[c - 060].offset |= (((unsigned)*data++) << 8);
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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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}
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if (c >= 064 && c <= 066) {
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ins->oprs[c - 064].offset = *data++;
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ins->oprs[c - 064].offset |= (((unsigned)*data++) << 8);
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if (osize == 32) {
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ins->oprs[c - 064].offset |= (((long)*data++) << 16);
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ins->oprs[c - 064].offset |= (((long)*data++) << 24);
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ins->oprs[c - 064].segment |= SEG_32BIT;
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} else
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ins->oprs[c - 064].segment &= ~SEG_32BIT;
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ins->oprs[c - 064].segment |= SEG_RELATIVE;
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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 & NON_SIZE)
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| ((osize == 16) ? BITS16 : BITS32);
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}
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}
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if (c >= 070 && c <= 072) {
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ins->oprs[c - 070].offset = *data++;
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ins->oprs[c - 070].offset |= (((unsigned)*data++) << 8);
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ins->oprs[c - 070].offset |= (((long)*data++) << 16);
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ins->oprs[c - 070].offset |= (((long)*data++) << 24);
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ins->oprs[c - 070].segment |= SEG_32BIT | SEG_RELATIVE;
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}
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if (c >= 0100 && c < 0130) {
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int modrm = *data++;
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ins->oprs[c & 07].basereg = (modrm >> 3) & 07;
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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]);
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}
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if (c >= 0130 && c <= 0132) {
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ins->oprs[c - 0130].offset = *data++;
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ins->oprs[c - 0130].offset |= (((unsigned)*data++) << 8);
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}
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if (c >= 0140 && c <= 0142) {
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ins->oprs[c - 0140].offset = *data++;
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ins->oprs[c - 0140].offset |= (((unsigned)*data++) << 8);
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ins->oprs[c - 0140].offset |= (((long)*data++) << 16);
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ins->oprs[c - 0140].offset |= (((long)*data++) << 24);
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}
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if (c >= 0200 && c <= 0277) {
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int modrm = *data++;
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if (((modrm >> 3) & 07) != (c & 07))
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return FALSE; /* spare field doesn't match up */
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data = do_ea(data, modrm, asize, segsize,
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&ins->oprs[(c >> 3) & 07]);
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}
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if (c >= 0300 && c <= 0302) {
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if (asize)
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ins->oprs[c - 0300].segment |= SEG_32BIT;
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else
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ins->oprs[c - 0300].segment &= ~SEG_32BIT;
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a_used = TRUE;
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}
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if (c == 0310) {
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if (asize == 32)
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return FALSE;
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else
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a_used = TRUE;
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}
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if (c == 0311) {
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if (asize == 16)
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return FALSE;
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else
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a_used = TRUE;
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}
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if (c == 0312) {
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if (asize != segsize)
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return FALSE;
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else
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a_used = TRUE;
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}
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if (c == 0320) {
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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 outbufsize, int segsize,
|
|
long offset, int autosync, unsigned long prefer)
|
|
{
|
|
struct itemplate **p, **best_p;
|
|
int length, best_length = 0;
|
|
char *segover;
|
|
int rep, lock, asize, osize, i, slen, colon;
|
|
unsigned char *origdata;
|
|
int works;
|
|
insn tmp_ins, ins;
|
|
unsigned long goodness, best;
|
|
|
|
/*
|
|
* Scan for prefixes.
|
|
*/
|
|
asize = osize = segsize;
|
|
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 || *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) ^ prefer;
|
|
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)
|
|
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.
|
|
*/
|
|
if (lock)
|
|
slen += snprintf(output + slen, outbufsize - slen, "lock ");
|
|
for (i = 0; i < ins.nprefix; i++)
|
|
switch (ins.prefixes[i]) {
|
|
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))
|
|
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);
|
|
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] & 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%lx",
|
|
ins.oprs[i].offset);
|
|
} else if (!(MEM_OFFS & ~(*p)->opd[i])) {
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - 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 +=
|
|
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 == 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 sign = '+';
|
|
if (ins.oprs[i].offset & 0x80) {
|
|
ins.oprs[i].offset = -(signed char)ins.oprs[i].offset;
|
|
sign = '-';
|
|
}
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "%c0x%lx",
|
|
sign, ins.oprs[i].offset);
|
|
} else if (ins.oprs[i].segment & SEG_DISP16) {
|
|
if (started)
|
|
output[slen++] = '+';
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "0x%lx",
|
|
ins.oprs[i].offset);
|
|
} else if (ins.oprs[i].segment & SEG_DISP32) {
|
|
if (started)
|
|
output[slen++] = '+';
|
|
slen +=
|
|
snprintf(output + slen, outbufsize - slen, "0x%lx",
|
|
ins.oprs[i].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;
|
|
}
|
|
|
|
long eatbyte(unsigned char *data, char *output, int outbufsize)
|
|
{
|
|
snprintf(output, outbufsize, "db 0x%02X", *data);
|
|
return 1;
|
|
}
|