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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
// =============================================================
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;
// NOTE: Parse data payload
// =============================================================
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
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
// =============================================================
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;
case S86_InstructionType_MOVMemToAccum: {

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project.rdbg
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