test & fix indirection & predecrement

1 files changed, 15 insertions, 0 deletions

diff --git a/src/vm/instruction.js b/src/vm/instruction.js
index c991643..c9048e1 100644
--- a/src/vm/instruction.js
+++ b/src/vm/instruction.js
@@ -22,3 +22,18 @@ exports.MOV = function(core, pc, ins) {
 
 	return [pc + 1];
 }
+
+
+exports.ADD = function(core, pc, ins) {
+	if (ins.a.mode === AddrMode.Immediate) {
+		const dst = core.getValue(pc, ins.b);
+		dst.b.value += ins.a.value;
+	} else {
+		const src = core.getValue(pc, ins.a);
+		const dst = core.getValue(pc, ins.b);
+		dst.a.value += src.a.value;
+		dst.b.value += src.b.value;
+	}
+
+	return [pc + 1];
+}