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perfaware/part1: Fix OOB 'w' bitshift for IMM->Reg, print signed output

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doyle 2023-03-08 08:24:20 +11:00 committed by committed-name
parent afa73e8475
commit 2a17186f74
2 changed files with 4 additions and 4 deletions
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8
part1/sim8086.c
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@ -441,23 +441,23 @@ int main(int argc, char **argv)
// NOTE: Parse opcode control bits // NOTE: Parse opcode control bits
// ============================================================= // =============================================================
S86_ASSERT(stream.size == 1); S86_ASSERT(stream.size == 1);
uint8_t w = (stream.bytes[0] & 0b0000'1000) >> 4; uint8_t w = (stream.bytes[0] & 0b0000'1000) >> 3;
uint8_t reg = (stream.bytes[0] & 0b0000'0111) >> 0; uint8_t reg = (stream.bytes[0] & 0b0000'0111) >> 0;
// NOTE: Parse data payload // NOTE: Parse data payload
// ============================================================= // =============================================================
stream.bytes[stream.size++] = S86_BufferIteratorNextByte(&buffer_it); stream.bytes[stream.size++] = S86_BufferIteratorNextByte(&buffer_it);
uint16_t data = stream.bytes[stream.size - 1]; int16_t data = stream.bytes[stream.size - 1];
if (w) { // 16 bit data if (w) { // 16 bit data
stream.bytes[stream.size++] = S86_BufferIteratorNextByte(&buffer_it); stream.bytes[stream.size++] = S86_BufferIteratorNextByte(&buffer_it);
data |= (uint16_t)(stream.bytes[stream.size - 1]) << 8; data |= (int16_t)(stream.bytes[stream.size - 1]) << 8;
} }
// NOTE: Disassemble // NOTE: Disassemble
// ============================================================= // =============================================================
S86_Str8 dest_register = REGISTER_FIELD_ENCODING[w][reg]; S86_Str8 dest_register = REGISTER_FIELD_ENCODING[w][reg];
S86_PrintLnFmt("mov %.*s, %u", S86_STR8_FMT(dest_register), data); S86_PrintLnFmt("mov %.*s, %d", S86_STR8_FMT(dest_register), data);
} break; } break;
case S86_InstructionType_MOVMemToAccum: { case S86_InstructionType_MOVMemToAccum: {

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project.rdbg
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