From 2a17186f74a54b84f653af88694db4c892e5578a Mon Sep 17 00:00:00 2001
From: doyle <doyle.github.2ifxi@simplelogin.com>
Date: Wed, 8 Mar 2023 08:24:20 +1100
Subject: [PATCH] perfaware/part1: Fix OOB 'w' bitshift for IMM->Reg, print
 signed output

---
 part1/sim8086.c |   8 ++++----
 project.rdbg    | Bin 914 -> 1002 bytes
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/part1/sim8086.c b/part1/sim8086.c
index 0e764e4..31a918c 100644
--- a/part1/sim8086.c
+++ b/part1/sim8086.c
@@ -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: {
diff --git a/project.rdbg b/project.rdbg
index 4aa0a50d261d1c8fc466f5408261bf60781b5672..21eb7d33bbac1c06a4d8933761e38853fef5ae04 100644
GIT binary patch
delta 81
zcmbQl{)&CVK3+x!2msOcllvJhxr;M%EetHo^pZIkCmz_#36fyr{&|FPavkFrR*+)$
W$qSj}!Qvn}#>pR<JSIP5S_1&x+7gxk

delta 39
ucmaFGK8bz8J|+f+$^49a85t&DW&FYl<T0>MW@J`p<eD7F>^|9!c?|&DZ3-R$