From 55db78a15dc5f42be838d27c941a5124684aefb1 Mon Sep 17 00:00:00 2001
From: Ain <41307858+nero@users.noreply.github.com>
Date: Wed, 2 Oct 2019 22:35:48 +0000
Subject: [PATCH] Clean up code for conditional jumps

Amended: A binary file got in there
---
 utils/emul.c | 28 +++++++++++-----------------
 1 file changed, 11 insertions(+), 17 deletions(-)

diff --git a/utils/emul.c b/utils/emul.c
index 08014d5..35dc2cd 100644
--- a/utils/emul.c
+++ b/utils/emul.c
@@ -192,22 +192,6 @@ void modrm(int size) {
   if (mod == 2) rmptr += (int16_t)imm16();
 }
 
-int cond(int num) {
-  int r = 0;
-  switch(num >> 1) {
-  case 2:
-    r = !scratch;
-    break;
-  default:
-    fprintf(stderr, "Condition code %d not implemented\n", num);
-    exit(1);
-    break;
-  }
-  // Each odd condition is the negation of the previous
-  if (num & 1) r=1-r;
-  return r;
-}
-
 void push(uint16_t v) {
   SP -= 2;
   *(uint16_t*)&mem[SP] = v;
@@ -296,7 +280,17 @@ void step() {
     break;
   case 0x70 ... 0x7F: // Jcc
     reg = ip + (int8_t)imm8();
-    if (cond(opcode-0x70)) {
+    switch((opcode-0x70) >> 1) {
+    case 0: scratch = flags.bit.o; break;
+    case 1: scratch = flags.bit.s; break;
+    case 2: scratch = flags.bit.z; break;
+    case 3: scratch = flags.bit.c; break;
+    case 4: scratch = flags.bit.c || flags.bit.z; break;
+    case 5: scratch = flags.bit.s != flags.bit.o; break;
+    case 6: scratch = flags.bit.z || flags.bit.s != flags.bit.o; break;
+    case 7: scratch = flags.bit.p; break;
+    }
+    if (!!(opcode & 1) != scratch) {
       ip = reg;
     }
     break;