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Implement memory decoding

This commit is contained in:
Jeffrey Pfau 2013-11-01 02:12:34 -07:00
parent f32155526b
commit 39e1a85ffc
2 changed files with 50 additions and 5 deletions
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52
src/arm/decoder-thumb.c
View File

@ -29,7 +29,7 @@
DEFINE_THUMB_DECODER(NAME, MNEMONIC, \ DEFINE_THUMB_DECODER(NAME, MNEMONIC, \
info->op1.reg = opcode & 0x0007; \ info->op1.reg = opcode & 0x0007; \
info->memory.baseReg = (opcode >> 3) & 0x0007; \ info->memory.baseReg = (opcode >> 3) & 0x0007; \
info->memory.offset.shifterReg = IMMEDIATE << 2; \ info->memory.offset.immediate = IMMEDIATE << 2; \
info->operandFormat = ARM_OPERAND_REGISTER_1 | \ info->operandFormat = ARM_OPERAND_REGISTER_1 | \
ARM_OPERAND_AFFECTED_1 | \ ARM_OPERAND_AFFECTED_1 | \
ARM_OPERAND_MEMORY_2; \ ARM_OPERAND_MEMORY_2; \
@ -333,7 +333,7 @@ static int _decodeRegisterList(int list, char* buffer, int blen) {
if (blen <= 0) { if (blen <= 0) {
return 0; return 0;
} }
int total = 1; int total = 0;
strncpy(buffer, "{", blen); strncpy(buffer, "{", blen);
ADVANCE(1); ADVANCE(1);
int i; int i;
@ -381,8 +381,52 @@ static int _decodeRegisterList(int list, char* buffer, int blen) {
} }
static int _decodeMemory(struct ARMMemoryAccess memory, char* buffer, int blen) { static int _decodeMemory(struct ARMMemoryAccess memory, char* buffer, int blen) {
// TODO if (blen <= 0) {
return 0; return 0;
}
int total = 0;
strncpy(buffer, "[", blen);
ADVANCE(1);
int written;
if (memory.format & ARM_MEMORY_REGISTER_BASE) {
written = _decodeRegister(memory.baseReg, buffer, blen);
ADVANCE(written);
if (memory.format & (ARM_MEMORY_REGISTER_OFFSET | ARM_MEMORY_IMMEDIATE_OFFSET) && !(memory.format & ARM_MEMORY_POST_INCREMENT)) {
strncpy(buffer, ", ", blen);
ADVANCE(2);
}
}
if (memory.format & ARM_MEMORY_POST_INCREMENT) {
strncpy(buffer, "], ", blen);
ADVANCE(3);
}
if (memory.format & ARM_MEMORY_IMMEDIATE_OFFSET) {
if (memory.format & ARM_MEMORY_OFFSET_SUBTRACT) {
written = snprintf(buffer, blen, "#-%i", memory.offset.immediate);
ADVANCE(written);
} else {
written = snprintf(buffer, blen, "#%i", memory.offset.immediate);
ADVANCE(written);
}
} else if (memory.format & ARM_MEMORY_REGISTER_OFFSET) {
if (memory.format & ARM_MEMORY_OFFSET_SUBTRACT) {
strncpy(buffer, "-", blen);
ADVANCE(1);
}
written = _decodeRegister(memory.offset.reg, buffer, blen);
ADVANCE(written);
}
// TODO: shifted registers
if (!(memory.format & ARM_MEMORY_POST_INCREMENT)) {
strncpy(buffer, "]", blen);
ADVANCE(1);
}
if (memory.format & ARM_MEMORY_PRE_INCREMENT) {
strncpy(buffer, "!", blen);
ADVANCE(1);
}
return total;
} }
static const char* _thumbMnemonicStrings[] = { static const char* _thumbMnemonicStrings[] = {

3
src/arm/decoder.h
View File

@ -43,7 +43,8 @@ enum ARMMemoryFormat {
ARM_MEMORY_REGISTER_OFFSET = 0x0004, ARM_MEMORY_REGISTER_OFFSET = 0x0004,
ARM_MEMORY_SHIFTED_OFFSET = 0x0008, ARM_MEMORY_SHIFTED_OFFSET = 0x0008,
ARM_MEMORY_PRE_INCREMENT = 0x0010, ARM_MEMORY_PRE_INCREMENT = 0x0010,
ARM_MEMORY_POST_INCREMENT = 0x0020 ARM_MEMORY_POST_INCREMENT = 0x0020,
ARM_MEMORY_OFFSET_SUBTRACT = 0x0040
}; };
union ARMOperand { union ARMOperand {