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better instruction trace

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mykola2312 2024-08-19 08:35:53 +03:00
parent b5dd5c455a
commit 97c8476d2a
1 changed files with 20 additions and 10 deletions
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30
src/rtdisasm.c
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@ -219,16 +219,26 @@ static unsigned value2length(uint8_t value)
}
#ifdef DEBUG
static void print_opcodes(const instruction_t* ins)
static void print_instruction(const instruction_t* ins)
{
fprintf(stderr, "opcodes ");
TRACE("type %u has_rex %u has_digit %u has_modrm %u has_imm %u has_value %u has_opreg %u",
ins->config.type,
ins->config.has_rex,
ins->config.has_digit,
ins->config.has_modrm,
ins->config.has_imm,
ins->config.has_value,
ins->config.has_opreg
);
fprintf(stderr, " opcodes ");
for (unsigned i = 0; i < ins->opcode_len; i++)
fprintf(stderr, "%02X ", ins->opcode[i]);
fprintf(stderr, "\n");
}
#else
#define print_opcodes(ins)
#define print_instruction(ins)
#endif
int rtdisasm_analyze_single(const uint8_t* code, unsigned size, const instruction_t** found)
@ -255,8 +265,6 @@ int rtdisasm_analyze_single(const uint8_t* code, unsigned size, const instructio
type = INSTRUCTION_VEX;
}
TRACE("type %d vex %d\n", type, vex);
// test if its rex prefix, if so we will look specifically for
// instructions with rex prefix
int rex = test_rex_prefix(*cur);
@ -266,16 +274,16 @@ int rtdisasm_analyze_single(const uint8_t* code, unsigned size, const instructio
if (++cur >= end) return -1;
}
TRACE("rex %d\n", rex);
const instruction_t* ins = find_instruction(cur, type, vex, rex);
if (!ins) return 0; // no instruction
print_opcodes(ins);
print_instruction(ins);
TRACE("type %d rex %d vex %d\n", type, rex, vex);
// since we now instruction, we need advance past opcode bytes
// since we found instruction, we need advance past opcode bytes
cur += ins->opcode_len;
if (cur >= end) return -1;
// don't check here for size limit, sicne size could be 1
// and opcode length 1 byte also
// if instruction has ModRM, we need to analyze it,
// since it can lead to SIB byte
@ -329,8 +337,10 @@ int rtdisasm_find_target(const uint8_t* code, unsigned size, unsigned rt_target)
int len = rtdisasm_analyze_single(cur, remaining, &ins);
// NOTE: this is ret passthru from analyze single,
// so it must be follow same ret logic as this function
TRACE("rtdisasm_analyze_single len %d\n", len);
if (len < 1) return len;
TRACE("ins->rt_target %u rt_target %u\n", ins->rt_target, rt_target);
if (ins->rt_target == rt_target)
{
// we found target instruction!