Get factorial working

concept-code/factorial.vsm

@@ -1,3 +1,6 @@
+@main = function() {
+  call @factorial [5] %return
+}
 @factorial = function(%n) {
   op!== %n 0 %notZero
   jmpif %notZero :recurse

src/vstc/virtual_machine/bytecode_decoder.rs

@@ -198,8 +198,10 @@ impl BytecodeDecoder {
       0x01 => Mov,
       0x02 => OpInc,
       0x04 => OpPlus,
+      0x05 => OpMinus,
       0x06 => OpMul,
       0x08 => OpMod,
+      0x0d => OpTripleNe,
       0x11 => OpLess,
       0x21 => Call,
       0x27 => Jmp,

src/vstc/virtual_machine/operations.rs

@@ -16,6 +16,10 @@ pub fn op_plus(left: &Val, right: &Val) -> Val {
   return VsNumber::from_f64(left_prim.to_number() + right_prim.to_number());
 }
 
+pub fn op_minus(left: &Val, right: &Val) -> Val {
+  return VsNumber::from_f64(left.to_number() - right.to_number());
+}
+
 pub fn op_mul(left: &Val, right: &Val) -> Val {
   return VsNumber::from_f64(left.to_number() * right.to_number());
 }
@@ -31,3 +35,11 @@ pub fn op_less(left: &Val, right: &Val) -> Val {
 
   return VsBool::from_bool(left.to_number() < right.to_number());
 }
+
+pub fn op_triple_ne(left: &Val, right: &Val) -> Val {
+  if left.typeof_() != VsType::Number || right.typeof_() != VsType::Number {
+    std::panic!("Not implemented");
+  }
+
+  return VsBool::from_bool(left.to_number() != right.to_number());
+}

src/vstc/virtual_machine/virtual_machine.rs

@@ -103,6 +103,17 @@ impl VirtualMachine {
         }
       },
 
+      OpMinus => {
+        let left = frame.decoder.decode_val(&frame.registers);
+        let right = frame.decoder.decode_val(&frame.registers);
+
+        let register_index = frame.decoder.decode_register_index();
+
+        if register_index.is_some() {
+          frame.registers[register_index.unwrap()] = operations::op_minus(&left, &right);
+        }
+      },
+
       OpMul => {
         let left = frame.decoder.decode_val(&frame.registers);
         let right = frame.decoder.decode_val(&frame.registers);
@@ -136,6 +147,17 @@ impl VirtualMachine {
         }
       }
 
+      OpTripleNe => {
+        let left = frame.decoder.decode_val(&frame.registers);
+        let right = frame.decoder.decode_val(&frame.registers);
+
+        let register_index = frame.decoder.decode_register_index();
+
+        if register_index.is_some() {
+          frame.registers[register_index.unwrap()] = operations::op_triple_ne(&left, &right);
+        }
+      }
+
       Call => {
         let fn_ = frame.decoder.decode_val(&frame.registers);
         let maybe_new_frame = fn_.make_frame();