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1044 lines
31 KiB
C++
1044 lines
31 KiB
C++
/* disarm -- a simple disassembler for ARM instructions
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* (c) 2000 Gareth McCaughan
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*
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* This file may be distributed and used freely provided:
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* 1. You do not distribute any version that lacks this
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* copyright notice (exactly as it appears here, extending
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* from the start to the end of the C-language comment
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* containing these words)); and,
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* 2. If you distribute any modified version, its source
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* contains a clear description of the ways in which
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* it differs from the original version, and a clear
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* indication that the changes are not mine.
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* There is no restriction on your permission to use and
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* distribute object code or executable code derived from
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* this.
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*
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* The original version of this file (or perhaps a later
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* version by the original author) may or may not be
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* available at http://web.ukonline.co.uk/g.mccaughan/g/software.html .
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*
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* Share and enjoy! -- g
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*/
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/* (*This* comment is NOT part of the notice mentioned in the
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* distribution conditions above.)
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*
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* The bulk of this code was ripped brutally from the middle
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* of a much more interesting piece of software whose purpose
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* is to disassemble object files in the format known as AOF;
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* it's quite clever at spotting blocks of non-code embedded
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* in code, identifying labels, and so on.
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*
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* This program, on the other hand, is very much simpler.
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* It simply disassembles one instruction at a time. Some
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* traces of the original purpose can be seen here and there.
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* You might want to make this do a two-phase disassembly,
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* adding labels etc the second time around. I've made this
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* work by loading the whole file into memory first, partly
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* because that makes a two-pass approach easier.
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*
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* One word of warning: I believe that the syntax this program
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* uses for the MSR instruction is now obsolete.
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*
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* Usage:
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* disarm <filename> <base-address>
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* will disassemble every word in <filename>.
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*
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* <base-address> should be something understood by strtol.
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* So you can get hex (which is probably what you want)
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* by prefixing "0x".
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*
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* The -r option will byte-reverse each word before it's
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* disassembled.
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*
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* The code is rather unmaintainable. I'm sorry.
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*
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* Changes since original release:
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* ????-??-?? v0.00 Initial release.
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* 2007-09-02 v0.11 Change %X to %lX in a format string.
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* (Thanks to Vincent Zweije for reporting this.)
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "base/basictypes.h"
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#include "Common/ArmEmitter.h"
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static const char *CCFlagsStr[] = {
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"EQ", // Equal
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"NEQ", // Not equal
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"CS", // Carry Set
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"CC", // Carry Clear
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"MI", // Minus (Negative)
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"PL", // Plus
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"VS", // Overflow
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"VC", // No Overflow
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"HI", // Unsigned higher
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"LS", // Unsigned lower or same
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"GE", // Signed greater than or equal
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"LT", // Signed less than
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"GT", // Signed greater than
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"LE", // Signed less than or equal
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"", // Always (unconditional) 14
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};
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int GetVd(uint32_t op, bool quad = false, bool dbl = false) {
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if (!quad && !dbl) {
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return ((op >> 22) & 1) | ((op >> 11) & 0x1E);
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}
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return 0;
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}
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int GetVn(uint32_t op, bool quad = false, bool dbl = false) {
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if (!quad && !dbl) {
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return ((op >> 7) & 1) | ((op >> 15) & 0x1E);
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} else if (dbl) {
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return ((op >> 16) & 0xF) | ((op >> 3) & 0x10);
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}
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return 0;
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}
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int GetVm(uint32_t op, bool quad = false, bool dbl = false) {
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if (!quad && !dbl) {
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return ((op >> 5) & 1) | ((op << 1) & 0x1E);
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}
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return 0;
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}
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// Modern VFP disassembler, written entirely separately because I can't figure out the old stuff :P
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// Horrible array of hacks but hey. Can be cleaned up later.
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bool DisasmVFP(uint32_t op, char *text) {
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#if defined(ANDROID) && defined(_M_IX86)
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// Prevent linking errors with ArmEmitter which I've excluded on x86 android.
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strcpy(text, "ARM disasm not available");
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#else
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const char *cond = CCFlagsStr[op >> 28];
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switch ((op >> 24) & 0xF) {
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case 0xD:
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// VLDR/VSTR
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{
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int base = (op >> 16) & 0xF;
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bool add = (op >> 23) & 1;
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int freg = ((op >> 11) & 0x1E) | ((op >> 22) & 1);
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int offset = (op & 0xFF) << 2;
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if (!add) offset = -offset;
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bool vldr = (op >> 20) & 1;
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bool single_reg = ((op >> 8) & 0xF) == 10;
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sprintf(text, "%s%s s%i, [r%i, #%i]", vldr ? "VLDR" : "VSTR", cond, freg, base, offset);
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return true;
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}
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case 0xE:
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{
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switch ((op >> 20) & 0xF) {
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case 0xE: // VMSR
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if ((op & 0xFFF) != 0xA10)
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break;
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sprintf(text, "VMSR%s r%i", cond, (op >> 12) & 0xF);
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return true;
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case 0xF: // VMRS
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if ((op & 0xFFF) != 0xA10)
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break;
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if (op == 0xEEF1FA10) {
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sprintf(text, "VMRS%s APSR", cond);
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} else {
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sprintf(text, "VMRS%s r%i", cond, (op >> 12) & 0xF);
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}
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return true;
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default:
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break;
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}
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if (((op >> 19) & 0x7) == 0x7) {
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// VCVT
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sprintf(text, "VCVT ...");
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return true;
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}
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int part1 = ((op >> 23) & 0x1F);
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int part2 = ((op >> 9) & 0x7) ;
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int part3 = ((op >> 20) & 0x3) ;
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if (part3 == 3 && part2 == 5 && part1 == 0x1D && (op & (1<<6))) {
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// VMOV
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int vn = GetVn(op);
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if (vn != 1 && vn != 3) {
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int vm = GetVm(op);
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int vd = GetVd(op);
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sprintf(text, "VMOV%s s%i, s%i", cond, vd, vm);
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return true;
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}
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}
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// Arithmetic (buggy!)
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bool quad_reg = (op >> 6) & 1;
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bool double_reg = (op >> 8) & 1;
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int opnum = -1;
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int opc1 = (op >> 20) & 0xFB;
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int opc2 = (op >> 4) & 0xAC;
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for (int i = 0; i < 16; i++) {
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if (ArmGen::VFPOps[i][0].opc1 == opc1 && ArmGen::VFPOps[i][0].opc2 == opc2) {
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opnum = i;
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break;
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}
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}
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if (opnum < 0)
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return false;
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switch (opnum) {
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case 8:
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case 10:
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case 11:
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case 12:
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case 13:
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case 14:
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{
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quad_reg = false;
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int vd = GetVd(op, quad_reg, double_reg);
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int vn = GetVn(op, quad_reg, true);
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int vm = GetVm(op, quad_reg, double_reg);
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if (opnum == 8 && vn == 0x11) opnum += 3;
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sprintf(text, "%s%s s%i, s%i", ArmGen::VFPOpNames[opnum], cond, vd, vm);
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return true;
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}
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default:
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{
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quad_reg = false;
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int vd = GetVd(op, quad_reg, double_reg);
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int vn = GetVn(op, quad_reg, double_reg);
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int vm = GetVm(op, quad_reg, double_reg);
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sprintf(text, "%s%s s%i, s%i, s%i", ArmGen::VFPOpNames[opnum], cond, vd, vn, vm);
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return true;
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}
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}
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return true;
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}
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break;
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}
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#endif
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return false;
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}
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typedef unsigned int word;
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typedef unsigned int address;
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typedef unsigned int addrdiff;
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#define W(x) ((word*)(x))
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#define declstruct(name) typedef struct name s##name, * p##name
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#define defstruct(name) struct name
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#define defequiv(new,old) typedef struct old s##new, * p##new
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declstruct(DisOptions);
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declstruct(Instruction);
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typedef enum {
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target_None, /* instruction doesn't refer to an address */
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target_Data, /* instruction refers to address of data */
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target_FloatS, /* instruction refers to address of single-float */
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target_FloatD, /* instruction refers to address of double-float */
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target_FloatE, /* blah blah extended-float */
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target_FloatP, /* blah blah packed decimal float */
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target_Code, /* instruction refers to address of code */
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target_Unknown /* instruction refers to address of *something* */
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} eTargetType;
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defstruct(Instruction) {
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char text[128]; /* the disassembled instruction */
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int undefined; /* non-0 iff it's an undefined instr */
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int badbits; /* non-0 iff something reserved has the wrong value */
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int oddbits; /* non-0 iff something unspecified isn't 0 */
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int is_SWI; /* non-0 iff it's a SWI */
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word swinum; /* only set for SWIs */
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address target; /* address instr refers to */
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eTargetType target_type; /* and what we expect to be there */
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int offset; /* offset from register in LDR or STR or similar */
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char * addrstart; /* start of address part of instruction, or 0 */
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};
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#define disopt_SWInames 1 /* use names, not &nnnn */
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#define disopt_CommaSpace 2 /* put spaces after commas */
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#define disopt_FIXS 4 /* bogus FIX syntax for ObjAsm */
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#define disopt_ReverseBytes 8 /* byte-reverse words first */
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defstruct(DisOptions) {
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word flags;
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const char * * regnames; /* pointer to 16 |char *|s: register names */
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};
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static pInstruction instr_disassemble(word, address, pDisOptions);
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#define INSTR_grok_v4
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/* Preprocessor defs you can give to affect this stuff:
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* INSTR_grok_v4 understand ARMv4 instructions (halfword & sign-ext LDR/STR)
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* INSTR_new_msr be prepared to produce new MSR syntax if asked
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* The first of these is supported; the second isn't.
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*/
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/* Some important single-bit fields. */
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#define Sbit (1<<20) /* set condition codes (data processing) */
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#define Lbit (1<<20) /* load, not store (data transfer) */
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#define Wbit (1<<21) /* writeback (data transfer) */
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#define Bbit (1<<22) /* single byte (data transfer, SWP) */
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#define Ubit (1<<23) /* up, not down (data transfer) */
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#define Pbit (1<<24) /* pre-, not post-, indexed (data transfer) */
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#define Ibit (1<<25) /* non-immediate (data transfer) */
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/* immediate (data processing) */
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#define SPSRbit (1<<22) /* SPSR, not CPSR (MRS, MSR) */
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/* Some important 4-bit fields. */
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#define RD(x) ((x)<<12) /* destination register */
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#define RN(x) ((x)<<16) /* operand/base register */
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#define CP(x) ((x)<<8) /* coprocessor number */
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#define RDbits RD(15)
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#define RNbits RN(15)
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#define CPbits CP(15)
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#define RD_is(x) ((instr&RDbits)==RD(x))
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#define RN_is(x) ((instr&RNbits)==RN(x))
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#define CP_is(x) ((instr&CPbits)==CP(x))
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/* A slightly efficient way of telling whether two bits are the same
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* or not. It's assumed that a<b.
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*/
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#define BitsDiffer(a,b) ((instr^(instr>>(b-a)))&(1<<a))
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/* op = append(op,ip) === op += sprintf(op,"%s",ip),
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* except that it's faster.
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*/
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static char * append(char * op, const char *ip) {
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char c;
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while ((c=*ip++)!=0) *op++=c;
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return op;
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}
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/* op = hex8(op,w) === op += sprintf(op,"&%08lX",w), but faster.
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*/
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static char * hex8(char * op, word w) {
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int i;
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*op++='&';
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for (i=28; i>=0; i-=4) *op++ = "0123456789ABCDEF"[(w>>i)&15];
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return op;
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}
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/* op = reg(op,'x',n) === op += sprintf(op,"x%lu",n&15).
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*/
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static char * reg(char * op, char c, word n) {
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*op++=c;
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n&=15;
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if (n>=10) { *op++='1'; n+='0'-10; } else n+='0';
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*op++=(char)n;
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return op;
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}
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/* op = num(op,n) appends n in decimal or &n in hex
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* depending on whether n<100. It's assumed that n>=0.
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*/
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static char * num(char * op, word w) {
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if (w>=100) {
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int i;
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word t;
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*op++='&';
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for (i=28; (t=(w>>i)&15)==0; i-=4) ;
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for (; i>=0; i-=4) *op++ = "0123456789ABCDEF"[(w>>i)&15];
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}
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else {
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/* divide by 10. You can prove this works by exhaustive search. :-) */
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word t = w-(w>>2); t=(t+(t>>4)) >> 3;
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{ word u = w-10*t;
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if (u==10) { u=0; ++t; }
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if (t) *op++=(char)(t+'0');
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*op++=(char)(u+'0');
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}
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}
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return op;
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}
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/* instr_disassemble
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* Disassemble a single instruction.
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*
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* args: instr a single ARM instruction
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* addr the address it's presumed to have come from
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* opts cosmetic preferences for our output
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*
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* reqs: opts must be filled in right. In particular, it must contain
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* a list of register names.
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*
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* return: a pointer to a structure containing the disassembled instruction
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* and some other information about it.
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*
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* This is basically a replacement for the SWI Debugger_Disassemble,
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* but it has the following advantages:
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*
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* + it's 3-4 times as fast
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* + it's better at identifying undefined instructions,
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* and instructions not invariant under { disassemble; ObjAsm; }
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* + it provides some other useful information as well
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* + its output syntax is the same as ObjAsm's input syntax
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* (where possible)
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* + it doesn't disassemble FIX incorrectly unless you ask it to
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* + it's more configurable in some respects
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*
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* It also has the following disadvantages:
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*
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* - it increases the size of ObjDism
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* - it doesn't provide so many `helpful' usage comments etc
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* - it's less configurable in some respects
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* - it doesn't (yet) know about ARMv4 instructions
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*
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* This function proceeds in two phases. The first is very simple:
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* it works out what sort of instruction it's looking at and sets up
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* three strings:
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* - |mnemonic| (the basic mnemonic: LDR or whatever)
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* - |flagchars| (things to go after the cond code: B or whatever)
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* - |format| (a string describing how to display the instruction)
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* The second phase consists of interpreting |format|, character by
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* character. Some characters (e.g., letters) just mean `append this
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* character to the output string'; some mean more complicated things
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* like `append the name of the register whose number is in bits 12..15'
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* or, worse, `append a description of the <op2> field'.
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*
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* I'm afraid the magic characters in |format| are rather arbitrary.
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* One criterion in choosing them was that they should form a contiguous
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* subrange of the character set! Sorry.
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*
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* Things I still want to do:
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*
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* - more configurability?
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* - make it much faster, if possible
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* - make it much smaller, if possible
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*
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* Format characters:
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*
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* \01..\05 copro register number from nybble (\001 == nybble 0, sorry)
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* $ SWI number
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* % register set for LDM/STM (takes note of bit 22 for ^)
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* & address for B/BL
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* ' ! if bit 21 set, else nothing (mnemonic: half a !)
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* ( #regs for SFM (bits 22,15 = fpn, assumed already tweaked)
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* ) copro opcode in bits 20..23 (for CDP)
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* * op2 (takes note of bottom 12 bits, and bit 25)
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* + FP register or immediate value: bits 0..3
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* , comma or comma-space
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* - copro extra info in bits 5..7 preceded by , omitted if 0
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* . address in ADR instruction
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* / address for LDR/STR (takes note of bit 23 & reg in bits 16..19)
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* 0..4 register number from nybble
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* 5..9 FP register number from nybble
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* : copro opcode in bits 21..23 (for MRC/MCR)
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* ; copro number in bits 8..11
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*
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* ADDED BY HRYDGARD:
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* ^ 16-bit immediate
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*
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* NB that / takes note of bit 22, too, and does its own ! when
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* appropriate.
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*
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* On typical instructions this seems to take about 100us on my ARM6;
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* that's about 3000 cycles, which seems grossly excessive. I'm not
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* sure where all those cycles are being spent. Perhaps it's possible
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* to make it much, much faster. Most of this time is spent on phase 2.
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*/
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extern pInstruction
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instr_disassemble(word instr, address addr, pDisOptions opts) {
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static char flagchars[4];
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static sInstruction result;
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const char * mnemonic = 0;
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char * flagp = flagchars;
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const char * format = 0;
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word fpn;
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eTargetType poss_tt = target_None;
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#ifdef INSTR_grok_v4
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int is_v4 = 0;
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#endif
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|
|
/* PHASE 0. Set up default values for |result|. */
|
|
|
|
if (opts->flags & disopt_ReverseBytes) {
|
|
instr = ((instr & 0xFF00FF00) >> 8) | ((instr & 0x00FF00FF) << 8);
|
|
instr = (instr >> 16) | (instr << 16);
|
|
}
|
|
|
|
fpn = ((instr>>15)&1) + ((instr>>21)&2);
|
|
|
|
result.undefined = 0;
|
|
result.badbits = 0;
|
|
result.oddbits = 0;
|
|
result.is_SWI = 0;
|
|
result.target_type = target_None;
|
|
result.offset = 0x80000000;
|
|
result.addrstart = 0;
|
|
|
|
/* PHASE 1. Decode and classify instruction. */
|
|
|
|
switch ((instr>>24)&15) {
|
|
case 0:
|
|
/* multiply or data processing, or LDRH etc */
|
|
if ((instr&(15<<4))!=(9<<4)) goto lMaybeLDRHetc;
|
|
/* multiply */
|
|
if (instr&(1<<23)) {
|
|
/* int multiply */
|
|
mnemonic = "UMULL\0UMLAL\0SMULL\0SMLAL" + 6*((instr>>21)&3);
|
|
format = "3,4,0,2";
|
|
}
|
|
else {
|
|
if (instr&(1<<22)) goto lUndefined; /* "class C" */
|
|
/* short multiply */
|
|
if (instr&(1<<21)) {
|
|
mnemonic = "MLA";
|
|
format = "4,0,2,3";
|
|
}
|
|
else {
|
|
mnemonic = "MUL";
|
|
format = "4,0,2";
|
|
}
|
|
}
|
|
if (instr&Sbit) *flagp++='S';
|
|
break;
|
|
case 1:
|
|
if ((instr & 0x0FFFFFF0) == ((18 << 20) | (0xFFF << 8) | (1 << 4))) {
|
|
mnemonic = "B";
|
|
format = "0";
|
|
break;
|
|
} else if ((instr & 0x0FFFFFF0) == 0x012FFF30) {
|
|
mnemonic = "BL";
|
|
format = "0";
|
|
break;
|
|
}
|
|
case 3:
|
|
/* SWP or MRS/MSR or data processing */
|
|
// hrydgard addition: MOVW/MOVT
|
|
if ((instr & 0x0FF00000) == 0x03000000) {
|
|
mnemonic = "MOVW";
|
|
format = "3,^";
|
|
break;
|
|
}
|
|
else if ((instr & 0x0FF00000) == 0x03400000) {
|
|
mnemonic = "MOVT";
|
|
format = "3,^";
|
|
break;
|
|
}
|
|
else if ((instr&0x02B00FF0)==0x00000090) {
|
|
/* SWP */
|
|
mnemonic = "SWP";
|
|
format = "3,0,[4]";
|
|
if (instr&Bbit) *flagp++='B';
|
|
break;
|
|
}
|
|
else if ((instr&0x02BF0FFF)==0x000F0000) {
|
|
/* MRS */
|
|
mnemonic = "MRS";
|
|
format = (instr&SPSRbit) ? "3,SPSR" : "3,CPSR";
|
|
break;
|
|
}
|
|
else if ((instr&0x02BFFFF0)==0x0029F000) {
|
|
/* MSR psr<P=0/1...>,Rs */
|
|
mnemonic = "MSR";
|
|
format = (instr&SPSRbit) ? "SPSR,0" : "CPSR,0";
|
|
break;
|
|
}
|
|
else if ((instr&0x00BFF000)==0x0028F000) {
|
|
/* MSR {C,S}PSR_flag,op2 */
|
|
mnemonic = "MSR";
|
|
format = (instr&SPSRbit) ? "SPSR_flg,*" : "CPSR_flg,*";
|
|
if (!(instr&Ibit) && (instr&(15<<4)))
|
|
#ifdef INSTR_grok_v4
|
|
goto lMaybeLDRHetc;
|
|
#else
|
|
goto lUndefined; /* shifted reg in MSR illegal */
|
|
#endif
|
|
break;
|
|
}
|
|
/* fall through here */
|
|
lMaybeLDRHetc:
|
|
#ifdef INSTR_grok_v4
|
|
if ((instr&(14<<24))==0
|
|
&& ((instr&(9<<4))==(9<<4))) {
|
|
/* Might well be LDRH or similar. */
|
|
if ((instr&(Wbit+Pbit))==Wbit) goto lUndefined; /* "class E", case 1 */
|
|
if ((instr&(Lbit+(1<<6)))==(1<<6)) goto lUndefined; /* STRSH etc */
|
|
mnemonic = "STR\0LDR" + ((instr&Lbit) >> 18);
|
|
if (instr&(1<<6)) *flagp++='S';
|
|
*flagp++ = (instr&(1<<5)) ? 'B' : 'H';
|
|
format = "3,/";
|
|
/* aargh: */
|
|
if (!(instr&(1<<22))) instr |= Ibit;
|
|
is_v4=1;
|
|
break;
|
|
}
|
|
#endif
|
|
case 2:
|
|
/* data processing */
|
|
{ word op21 = instr&(15<<21);
|
|
if ((op21==(2<<21) || (op21==(4<<21))) /* ADD or SUB */
|
|
&& ((instr&(RNbits+Ibit+Sbit))==RN(15)+Ibit) /* imm, no S */
|
|
/*&& ((instr&(30<<7))==0 || (instr&3))*/) { /* normal rot */
|
|
/* ADD ...,pc,#... or SUB ...,pc,#...: turn into ADR */
|
|
mnemonic = "ADR";
|
|
format = "3,.";
|
|
if ((instr&(30<<7))!=0 && !(instr&3)) result.oddbits=1;
|
|
break;
|
|
}
|
|
mnemonic = "AND\0EOR\0SUB\0RSB\0ADD\0ADC\0SBC\0RSC\0"
|
|
"TST\0TEQ\0CMP\0CMN\0ORR\0MOV\0BIC\0MVN" /* \0 */
|
|
+ (op21 >> 19);
|
|
/* Rd needed for all but TST,TEQ,CMP,CMN (8..11) */
|
|
/* Rn needed for all but MOV,MVN (13,15) */
|
|
if (op21 < ( 8<<21)) format = "3,4,*";
|
|
else if (op21 < (12<<21)) {
|
|
format = "4,*";
|
|
if (instr&RDbits) {
|
|
if ((instr&Sbit) && RD_is(15))
|
|
*flagp++='P';
|
|
else result.oddbits=1;
|
|
}
|
|
if (!(instr&Sbit)) goto lUndefined; /* CMP etc, no S bit */
|
|
}
|
|
else if (op21 & (1<<21)) {
|
|
format = "3,*";
|
|
if (instr&RNbits) result.oddbits=1;
|
|
}
|
|
else format = "3,4,*";
|
|
if (instr&Sbit && (op21<(8<<21) || op21>=(12<<21))) *flagp++='S';
|
|
}
|
|
break;
|
|
case 4:
|
|
case 5:
|
|
case 6:
|
|
case 7:
|
|
/* undefined or STR/LDR */
|
|
if ((instr&Ibit) && (instr&(1<<4))) goto lUndefined; /* "class A" */
|
|
mnemonic = "STR\0LDR" + ((instr&Lbit) >> 18);
|
|
format = "3,/";
|
|
if (instr&Bbit) *flagp++='B';
|
|
if ((instr&(Wbit+Pbit))==Wbit) *flagp++='T';
|
|
poss_tt = target_Data;
|
|
break;
|
|
case 8:
|
|
case 9:
|
|
/* STM/LDM */
|
|
mnemonic = "STM\0LDM" + ((instr&Lbit) >> 18);
|
|
if (RN_is(13)) {
|
|
/* r13, so treat as stack */
|
|
word x = (instr&(3<<23)) >> 22;
|
|
if (instr&Lbit) x^=6;
|
|
{ const char * foo = "EDEAFDFA"+x;
|
|
*flagp++ = *foo++;
|
|
*flagp++ = *foo;
|
|
}
|
|
}
|
|
else {
|
|
/* not r13, so don't treat as stack */
|
|
*flagp++ = (instr&Ubit) ? 'I' : 'D';
|
|
*flagp++ = (instr&Pbit) ? 'B' : 'A';
|
|
}
|
|
format = "4',%";
|
|
break;
|
|
case 10:
|
|
case 11:
|
|
/* B or BL */
|
|
mnemonic = "B\0BL"+((instr&(1<<24))>>23);
|
|
format = "&";
|
|
break;
|
|
case 12:
|
|
case 13:
|
|
case 14: // FPU
|
|
{
|
|
char text[128];
|
|
if (!DisasmVFP(instr, text)) {
|
|
goto lUndefined;
|
|
break;
|
|
}
|
|
strcpy(result.text, text);
|
|
result.undefined = 0;
|
|
return &result;
|
|
}
|
|
break;
|
|
case 15:
|
|
/* SWI */
|
|
mnemonic = "SWI";
|
|
format = "$";
|
|
break;
|
|
/* Nasty hack: this is code that won't be reached in the normal
|
|
* course of events, and after the last case of the switch is a
|
|
* convenient place for it.
|
|
*/
|
|
lUndefined:
|
|
strcpy(result.text, "Undefined instruction");
|
|
result.undefined = 1;
|
|
return &result;
|
|
}
|
|
*flagp=0;
|
|
|
|
/* PHASE 2. Produce string. */
|
|
|
|
{ char * op = result.text;
|
|
|
|
/* 2a. Mnemonic. */
|
|
|
|
op = append(op,mnemonic);
|
|
|
|
/* 2b. Condition code. */
|
|
|
|
{ word cond = instr>>28;
|
|
if (cond!=14) {
|
|
const char * ip = "EQNECSCCMIPLVSVCHILSGELTGTLEALNV"+2*cond;
|
|
*op++ = *ip++;
|
|
*op++ = *ip;
|
|
}
|
|
}
|
|
|
|
/* 2c. Flags. */
|
|
|
|
{ const char * ip = flagchars;
|
|
while (*ip) *op++ = *ip++;
|
|
}
|
|
|
|
/* 2d. A tab character. */
|
|
|
|
*op++ = '\t';
|
|
|
|
/* 2e. Other stuff, determined by format string. */
|
|
|
|
{ const char * ip = format;
|
|
char c;
|
|
|
|
const char * * regnames = opts->regnames;
|
|
word oflags = opts->flags;
|
|
|
|
while ((c=*ip++) != 0) {
|
|
switch(c) {
|
|
case '^': // hrydgard addition
|
|
{
|
|
unsigned short imm16 = ((instr & 0x000F0000) >> 4) | (instr & 0x0FFF);
|
|
op += sprintf(op, "%04x", imm16);
|
|
}
|
|
break;
|
|
case '$':
|
|
result.is_SWI = 1;
|
|
result.swinum = instr&0x00FFFFFF;
|
|
result.addrstart = op;
|
|
op += sprintf(op, "&%X", result.swinum);
|
|
break;
|
|
case '%':
|
|
*op++='{';
|
|
{ word w = instr&0xFFFF;
|
|
int i=0;
|
|
while (w) {
|
|
int j;
|
|
while (!(w&(1ul<<i))) ++i;
|
|
for (j=i+1; w&(1ul<<j); ++j) ;
|
|
--j;
|
|
/* registers [i..j] */
|
|
op = append(op, regnames[i]);
|
|
if (j-i) {
|
|
*op++ = (j-i>1) ? '-' : ',';
|
|
op = append(op, regnames[j]);
|
|
}
|
|
i=j; w=(w>>(j+1))<<(j+1);
|
|
if (w) *op++=',';
|
|
}
|
|
}
|
|
*op++='}';
|
|
if (instr&(1<<22)) *op++='^';
|
|
break;
|
|
case '&':
|
|
{ address target = (addr+8 + ((((int)instr)<<8)>>6)) & 0x03FFFFFC;
|
|
result.addrstart = op;
|
|
op = hex8(op, target);
|
|
result.target_type = target_Code;
|
|
result.target = target;
|
|
}
|
|
break;
|
|
case '\'':
|
|
lPling:
|
|
if (instr&Wbit) *op++='!';
|
|
break;
|
|
case '(':
|
|
*op++ = (char)('0'+fpn);
|
|
break;
|
|
case ')':
|
|
{ word w = (instr>>20)&15;
|
|
if (w>=10) { *op++='1'; *op++=(char)('0'-10+w); }
|
|
else *op++=(char)(w+'0');
|
|
}
|
|
break;
|
|
case '*':
|
|
case '.':
|
|
if (instr&Ibit) {
|
|
/* immediate constant */
|
|
word imm8 = (instr&255);
|
|
word rot = (instr>>7)&30;
|
|
if (rot && !(imm8&3) && c=='*') {
|
|
/* Funny immediate const. Guaranteed not '.', btw */
|
|
*op++='#'; *op++='&';
|
|
*op++="0123456789ABCDEF"[imm8>>4];
|
|
*op++="0123456789ABCDEF"[imm8&15];
|
|
*op++=',';
|
|
op = num(op, rot);
|
|
}
|
|
else {
|
|
imm8 = (imm8>>rot) | (imm8<<(32-rot));
|
|
if (c=='*') {
|
|
*op++='#';
|
|
if (imm8>256 && ((imm8&(imm8-1))==0)) {
|
|
/* only one bit set, and that later than bit 8.
|
|
* Represent as 1<<... .
|
|
*/
|
|
op = append(op,"1<<");
|
|
{ int n=0;
|
|
while (!(imm8&15)) { n+=4; imm8=imm8>>4; }
|
|
/* Now imm8 is 1, 2, 4 or 8. */
|
|
n += (0x30002010 >> 4*(imm8-1))&15;
|
|
op = num(op, n);
|
|
}
|
|
}
|
|
else {
|
|
if (((int)imm8)<0 && ((int)imm8)>-100) {
|
|
*op++='-'; imm8=-(int)imm8;
|
|
}
|
|
op = num(op, imm8);
|
|
}
|
|
}
|
|
else {
|
|
address a = addr+8;
|
|
if (instr&(1<<22)) a-=imm8; else a+=imm8;
|
|
result.addrstart=op;
|
|
op = hex8(op, a);
|
|
result.target=a; result.target_type=target_Unknown;
|
|
}
|
|
}
|
|
}
|
|
else {
|
|
/* rotated register */
|
|
const char * rot = "LSL\0LSR\0ASR\0ROR" + ((instr&(3<<5)) >> 3);
|
|
op = append(op, regnames[instr&15]);
|
|
if (instr&(1<<4)) {
|
|
/* register rotation */
|
|
if (instr&(1<<7)) goto lUndefined;
|
|
*op++=','; if (oflags&disopt_CommaSpace) *op++=' ';
|
|
op = append(op,rot); *op++=' ';
|
|
op = append(op,regnames[(instr&(15<<8))>>8]);
|
|
}
|
|
else {
|
|
/* constant rotation */
|
|
word n = instr&(31<<7);
|
|
if (!n) {
|
|
if (!(instr&(3<<5))) break;
|
|
else if ((instr&(3<<5))==(3<<5)) {
|
|
op = append(op, ",RRX");
|
|
break;
|
|
}
|
|
else n=32<<7;
|
|
}
|
|
*op++ = ','; if (oflags&disopt_CommaSpace) *op++=' ';
|
|
op = num(append(append(op,rot)," #"),n>>7);
|
|
}
|
|
}
|
|
break;
|
|
case '+':
|
|
if (instr&(1<<3)) {
|
|
word w = instr&7;
|
|
*op++='#';
|
|
if (w<6) *op++=(char)('0'+w);
|
|
else op = append(op, w==6 ? "0.5" : "10");
|
|
}
|
|
else {
|
|
*op++='f';
|
|
*op++=(char)('0'+(instr&7));
|
|
}
|
|
break;
|
|
case ',':
|
|
*op++=',';
|
|
if (oflags&disopt_CommaSpace) *op++=' ';
|
|
break;
|
|
case '-':
|
|
{ word w = instr&(7<<5);
|
|
if (w) {
|
|
*op++=',';
|
|
if (oflags&disopt_CommaSpace) *op++=' ';
|
|
*op++ = (char)('0'+(w>>5));
|
|
}
|
|
}
|
|
break;
|
|
case '/':
|
|
result.addrstart = op;
|
|
*op++='[';
|
|
op = append(op, regnames[(instr&RNbits)>>16]);
|
|
if (!(instr&Pbit)) *op++=']';
|
|
*op++=','; if (oflags&disopt_CommaSpace) *op++=' ';
|
|
/* For following, NB that bit 25 is always 0 for LDC, SFM etc */
|
|
if (instr&Ibit) {
|
|
/* shifted offset */
|
|
if (!(instr&Ubit)) *op++='-';
|
|
/* We're going to transfer to '*', basically. The stupid
|
|
* thing is that the meaning of bit 25 is reversed there;
|
|
* I don't know why the designers of the ARM did that.
|
|
*/
|
|
instr ^= Ibit;
|
|
if (instr&(1<<4)) {
|
|
#ifdef INSTR_grok_v4
|
|
if (is_v4 && !(instr&(15<<8))) {
|
|
ip = (instr&Pbit) ? "0]" : "0";
|
|
break;
|
|
}
|
|
#else
|
|
goto lUndefined; /* LSL r3 forbidden */
|
|
#endif
|
|
}
|
|
/* Need a ] iff it was pre-indexed; and an optional ! iff
|
|
* it's pre-indexed *or* a copro instruction,
|
|
* except that FPU operations don't need the !. Bletch.
|
|
*/
|
|
if (instr&Pbit) ip="*]'";
|
|
else if (instr&(1<<27)) {
|
|
if (CP_is(1) || CP_is(2)) {
|
|
if (!(instr&Wbit)) goto lUndefined;
|
|
ip="*";
|
|
}
|
|
else ip="*'";
|
|
}
|
|
else ip="*";
|
|
}
|
|
else {
|
|
/* immediate offset */
|
|
word offset;
|
|
if (instr&(1<<27)) {
|
|
/* LDF or LFM or similar */
|
|
offset = (instr&255)<<2;
|
|
}
|
|
#ifdef INSTR_grok_v4
|
|
else if (is_v4) offset = (instr&15) + ((instr&(15<<8))>>4);
|
|
#endif
|
|
else {
|
|
/* LDR or STR */
|
|
offset = instr&0xFFF;
|
|
}
|
|
*op++='#';
|
|
if (!(instr&Ubit)) {
|
|
if (offset) *op++='-';
|
|
else result.oddbits=1;
|
|
result.offset = -(int)offset;
|
|
}
|
|
else result.offset = offset;
|
|
op = num(op, offset);
|
|
if (RN_is(15) && (instr&Pbit)) {
|
|
/* Immediate, pre-indexed and PC-relative. Set target. */
|
|
result.target_type = poss_tt;
|
|
result.target = (instr&Ubit) ? addr+8 + offset
|
|
: addr+8 - offset;
|
|
if (!(instr&Wbit)) {
|
|
/* no writeback, either. Use friendly form. */
|
|
op = hex8(result.addrstart, result.target);
|
|
break;
|
|
}
|
|
}
|
|
if (instr&Pbit) { *op++=']'; goto lPling; }
|
|
else if (instr&(1<<27)) {
|
|
if (CP_is(1) || CP_is(2)) {
|
|
if (!(instr&Wbit)) goto lUndefined;
|
|
}
|
|
else goto lPling;
|
|
}
|
|
}
|
|
break;
|
|
case '0': case '1': case '2': case '3': case '4':
|
|
op = append(op, regnames[(instr>>(4*(c-'0')))&15]);
|
|
break;
|
|
case '5': case '6': case '7': case '8': case '9':
|
|
*op++='f';
|
|
*op++=(char)('0' + ((instr>>(4*(c-'5')))&7));
|
|
break;
|
|
case ':':
|
|
*op++ = (char)('0' + ((instr>>21)&7));
|
|
break;
|
|
case ';':
|
|
op = reg(op, 'p', instr>>8);
|
|
break;
|
|
default:
|
|
if (c<=5)
|
|
op = reg(op, 'c', instr >> (4*(c-1)));
|
|
else *op++ = c;
|
|
}
|
|
}
|
|
*op=0;
|
|
}
|
|
}
|
|
|
|
/* DONE! */
|
|
|
|
return &result;
|
|
}
|
|
|
|
static const char * reg_names[16] = {
|
|
"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
|
|
"r8", "r9", "r10", "r11", "ip", "sp", "lr", "pc"
|
|
};
|
|
|
|
static sDisOptions options = {
|
|
disopt_CommaSpace,
|
|
reg_names
|
|
};
|
|
|
|
const char *ArmRegName(int r) {
|
|
return reg_names[r];
|
|
}
|
|
void ArmDis(unsigned int addr, unsigned int w, char *output) {
|
|
pInstruction instr = instr_disassemble(w, addr, &options);
|
|
char temp[256];
|
|
sprintf(output, "%08x\t%s", w, instr->text);
|
|
if (instr->undefined || instr->badbits || instr->oddbits) {
|
|
if (instr->undefined) sprintf(output, " [undefined instr %08x]", w);
|
|
if (instr->badbits) sprintf(output, " [illegal bits %08x]", w);
|
|
|
|
// HUH? LDR and STR gets this a lot
|
|
// strcat(output, " ? (extra bits)");
|
|
if (instr->oddbits) sprintf(temp, " [unexpected bits %08x]", w), strcat(output, temp);
|
|
}
|
|
// zap tabs
|
|
while (*output) {
|
|
if (*output == '\t')
|
|
*output = ' ';
|
|
output++;
|
|
}
|
|
} |