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Begin disassembler

This commit is contained in:
Jeffrey Pfau 2013-11-01 01:47:04 -07:00
parent 58545f112e
commit e60cbfaf84
3 changed files with 164 additions and 12 deletions
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165
src/arm/decoder-thumb.c
View File

@ -4,6 +4,9 @@
#include "emitter-thumb.h"
#include "isa-inlines.h"
#include <stdio.h>
#include <string.h>
#define DEFINE_THUMB_DECODER(NAME, MNEMONIC, BODY) \
static void _ThumbDecode ## NAME (uint16_t opcode, struct ThumbInstructionInfo* info) { \
UNUSED(opcode); \
@ -200,18 +203,17 @@ DEFINE_LOAD_STORE_WITH_REGISTER_THUMB(STR2, STR)
DEFINE_LOAD_STORE_WITH_REGISTER_THUMB(STRB2, STRB)
DEFINE_LOAD_STORE_WITH_REGISTER_THUMB(STRH2, STRH)
#define DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(NAME, RN, MNEMONIC, SPECIAL_REG) \
#define DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(NAME, RN, MNEMONIC, SPECIAL_REG, ADDITIONAL_REG) \
DEFINE_THUMB_DECODER(NAME, MNEMONIC, \
info->memory.baseReg = RN; \
info->accessesSpecialRegisters = SPECIAL_REG; \
info->op1.immediate = opcode & 0xFF; \
info->operandFormat = ARM_OPERAND_IMMEDIATE_1 | \
ARM_OPERAND_AFFECTED_1; \
info->op1.immediate = (opcode & 0xFF) | ADDITIONAL_REG; \
info->operandFormat = ARM_OPERAND_IMMEDIATE_1; \
info->memory.format = ARM_MEMORY_REGISTER_BASE | \
ARM_MEMORY_POST_INCREMENT;)
#define DEFINE_LOAD_STORE_MULTIPLE_THUMB(NAME) \
COUNT_3(DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB, NAME ## _R, NAME, 0)
COUNT_3(DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB, NAME ## _R, NAME, 0, 0)
DEFINE_LOAD_STORE_MULTIPLE_THUMB(LDMIA)
DEFINE_LOAD_STORE_MULTIPLE_THUMB(STMIA)
@ -250,10 +252,10 @@ DEFINE_CONDITIONAL_BRANCH_THUMB(LE)
DEFINE_SP_MODIFY_THUMB(ADD7, ADD)
DEFINE_SP_MODIFY_THUMB(SUB4, SUB)
DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(POP, ARM_SP, POP, 1)
DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(POPR, ARM_SP, POP, 1)
DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(PUSH, ARM_SP, PUSH, 1)
DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(PUSHR, ARM_SP, PUSH, 1)
DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(POP, ARM_SP, POP, 1, 0)
DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(POPR, ARM_SP, POP, 1, 1 << ARM_PC)
DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(PUSH, ARM_SP, PUSH, 1, 0)
DEFINE_LOAD_STORE_MULTIPLE_EX_THUMB(PUSHR, ARM_SP, PUSH, 1, 1 << ARM_LR)
DEFINE_THUMB_DECODER(ILL, ILL, info->traps = 1;)
DEFINE_THUMB_DECODER(BKPT, BKPT, info->traps = 1;)
@ -301,3 +303,148 @@ void ARMDecodeThumb(uint16_t opcode, struct ThumbInstructionInfo* info) {
ThumbDecoder decoder = _thumbDecoderTable[opcode >> 6];
decoder(opcode, info);
}
#define ADVANCE(AMOUNT) \
if (AMOUNT > blen) { \
buffer[blen - 1] = '\0'; \
return total; \
} \
total += AMOUNT; \
buffer += AMOUNT; \
blen -= AMOUNT;
static int _decodeRegister(int reg, char* buffer, int blen) {
switch (reg) {
case ARM_SP:
strncpy(buffer, "sp", blen);
return 2;
case ARM_LR:
strncpy(buffer, "lr", blen);
return 2;
case ARM_PC:
strncpy(buffer, "pc", blen);
return 2;
default:
return snprintf(buffer, blen, "r%i", reg);
}
}
static int _decodeRegisterList(int list, char* buffer, int blen) {
if (blen <= 0) {
return 0;
}
int total = 1;
strncpy(buffer, "{", blen);
ADVANCE(1);
int i;
int start = -1;
int end = -1;
int written;
printf("%x\n", list);
for (i = 0; i <= ARM_PC; ++i) {
if (list & 1) {
if (start < 0) {
start = i;
end = i;
} else if (end + 1 == i) {
end = i;
} else {
if (end > start) {
written = _decodeRegister(start, buffer, blen);
ADVANCE(written);
strncpy(buffer, "-", blen);
ADVANCE(1);
}
written = _decodeRegister(end, buffer, blen);
ADVANCE(written);
strncpy(buffer, ",", blen);
ADVANCE(1);
start = i;
end = i;
}
}
list >>= 1;
}
if (start >= 0) {
if (end > start) {
written = _decodeRegister(start, buffer, blen);
ADVANCE(written);
strncpy(buffer, "-", blen);
ADVANCE(1);
}
written = _decodeRegister(end, buffer, blen);
ADVANCE(written);
}
strncpy(buffer, "}", blen);
ADVANCE(1);
return total;
}
static const char* _thumbMnemonicStrings[] = {
"ill",
"adc",
"add",
"and",
"asr",
"b",
"bic",
"bkpt",
"bl",
"blh",
"bx",
"cmn",
"cmp",
"eor",
"ldmia",
"ldr",
"ldrb",
"ldrh",
"ldrsb",
"ldrsh",
"lsl",
"lsr",
"mov",
"mul",
"mvn",
"neg",
"orr",
"pop",
"push",
"ror",
"sbc",
"stmia",
"str",
"strb",
"strh",
"sub",
"swi",
"tst"
};
int ARMDisassembleThumb(uint16_t opcode, char* buffer, int blen) {
struct ThumbInstructionInfo info;
ARMDecodeThumb(opcode, &info);
const char* mnemonic = _thumbMnemonicStrings[info.mnemonic];
int written;
int total = 0;
written = snprintf(buffer, blen, "%s ", mnemonic);
ADVANCE(written);
switch (info.mnemonic) {
case THUMB_MN_LDMIA:
case THUMB_MN_STMIA:
written = _decodeRegister(info.memory.baseReg, buffer, blen);
ADVANCE(written);
strncpy(buffer, "!, ", blen);
ADVANCE(3);
case THUMB_MN_POP:
case THUMB_MN_PUSH:
written = _decodeRegisterList(info.op1.immediate, buffer, blen);
ADVANCE(written);
break;
default:
break;
}
buffer[total] = '\0';
return total;
}

5
src/arm/decoder.h
View File

@ -99,7 +99,9 @@ enum ThumbMnemonic {
THUMB_MN_STRH,
THUMB_MN_SUB,
THUMB_MN_SWI,
THUMB_MN_TST
THUMB_MN_TST,
THUMB_MN_MAX
};
struct ThumbInstructionInfo {
@ -117,5 +119,6 @@ struct ThumbInstructionInfo {
};
void ARMDecodeThumb(uint16_t opcode, struct ThumbInstructionInfo* info);
int ARMDisassembleThumb(uint16_t opcode, char* buffer, int blen);
#endif

6
src/debugger/cli-debugger.c
View File

@ -1,4 +1,5 @@
#include "cli-debugger.h"
#include "decoder.h"
#include <signal.h>
#include <stdarg.h>
@ -137,13 +138,14 @@ static void _printHex(struct CLIDebugger* debugger, struct DebugVector* dv) {
}
static inline void _printLine(struct CLIDebugger* debugger, uint32_t address, enum ExecutionMode mode) {
// TODO: write a disassembler
char disassembly[32];
if (mode == MODE_ARM) {
uint32_t instruction = debugger->d.cpu->memory->load32(debugger->d.cpu->memory, address, 0);
printf("%08X\n", instruction);
} else {
uint16_t instruction = debugger->d.cpu->memory->loadU16(debugger->d.cpu->memory, address, 0);
printf("%04X\n", instruction);
ARMDisassembleThumb(instruction, disassembly, sizeof(disassembly));
printf("%04X: %s\n", instruction, disassembly);
}
}