lab17: part 2

lab17/op-codes.js

@@ -7,11 +7,16 @@ let opcodes = {
     vm.stack.push(v1+v2);
   }},
   0x02: { mnemonic: 'MUL', evaluate: (vm) => {
-    //
-    // **YOUR CODE HERE**
-    //
     // Pop the top two arguments off of the stack,
     // and then push the result on to the stack.
+    let v1 = vm.stack.pop();
+    let v2 = vm.stack.pop();
+    vm.stack.push(v1*v2);
+  }},
+  0x03: { mnemonic: 'SUB', evaluate: (vm) => {
+    let v1 = vm.stack.pop();
+    let v2 = vm.stack.pop();
+    vm.stack.push(v1-v2);
   }},
   0x5B: { mnemonic: 'JUMPDEST', evaluate: (vm) => {
     // Does nothing.  We could check to make sure that jumps
@@ -24,6 +29,12 @@ let opcodes = {
     let v = vm.bytecode.readUInt8(vm.pc);
     vm.stack.push(v);
   }},
+  0x90: { mnemonic: 'SWAP1', evaluate: (vm) => {
+    let v1 = vm.stack.pop();
+    let v2 = vm.stack.pop();
+    vm.stack.push(v1);
+    vm.stack.push(v2);
+  }},
   0x0c: { mnemonic: 'PRINT', evaluate: (vm) => {
     // **NOTE**: This is not a real EVM opcode.
     console.log(vm.stack.pop());