From e3fc06b083598f244b3949e06d4ffbd3d2b235cc Mon Sep 17 00:00:00 2001
From: mrb0nk500 <b0nk@b0nk.xyz>
Date: Mon, 11 Nov 2019 15:07:42 -0500
Subject: Added more instructions to the ALU.

---
 sux.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 79 insertions(+), 5 deletions(-)

(limited to 'sux.c')

diff --git a/sux.c b/sux.c
index 4e64277..43699d3 100644
--- a/sux.c
+++ b/sux.c
@@ -1,4 +1,3 @@
-#include <limits.h>
 #include "opcode.h"
 #include <stdint.h>
 uint64_t a; /* Accumulator. */
@@ -19,13 +18,88 @@ uint64_t alu(uint8_t opcode, uint64_t value) {
 			break;
 		/* Subtract with carry. */
 		case SBC:
-			sum = a-value-!carry
+			sum = a-value-!carry;
 			vf = (a^value) & (a^sum) & 0x80;
 			carry = (sum > value) ? 1 : 0;
 			a |= sum;
 			break;
-
-
-
+		/* Multiply with accumulator. */
+		case MUL:
+			sum = a*value+carry;
+			vf = (~(a^value) & (a^sum & 0x80));
+			carry = (sum < value) ? 1 : 0;
+			a |= sum;
+			break;
+		/* Divide with accumulator. */
+		case DIV:
+			sum = a/value-!carry;
+			vf = (a^value) & (a^sum) & 0x80;
+			carry = (sum > value) ? 1 : 0;
+			a |= sum;
+			break;
+		/* Bitwise AND. */
+		case AND:
+		case AAY:
+		case AAX:
+			a &= value;
+			if (opcode == AAY)
+				y &= value;
+			if (opcode == AAX)
+				x &= value;
+			break;
+		case ANY:
+			y &= value;
+			break;
+		case ANX:
+			x &= value;
+			break;
+		/* Bitwise OR. */
+		case ORA:
+		case OAY:
+		case OAX:
+			a |= value;
+			if (opcode == OAY)
+				y |= value;
+			if (opcode == OAX)
+				x |= value;
+			break;
+		case ORY:
+			y |= value;
+			break;
+		case ORX:
+			x |= value;
+			break;
+		/* Bitwise Exclusive OR. */
+		case XOR:
+		case XAY:
+		case XAX:
+			a ^= value;
+			if (opcode == XAY)
+				y ^= value;
+			if (opcode == XAX)
+				x ^= value;
+			break;
+		case XRY:
+			y ^= value;
+			break;
+		case XRX:
+			x ^= value;
+			break;
+		/* Shift accumulator left. */
+		case SLA:
+			a <<= value;
+			break;
+		/* Shift accumulator right. */
+		case SRA:
+			a >>= value;
+			break;
+		/* Rotate accumulator left. */
+		case ROL:
+			(a << value) | (a >> (64-value));
+			break;
+		/* Rotate accumulator right. */
+		case ROR:
+			(a >> value) | (a << (64-value));
+			break;
 	}
 }
-- 
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