diff --git a/src/asm/Instruction.go b/src/asm/Instruction.go
index 5990c20..d8f9889 100644
--- a/src/asm/Instruction.go
+++ b/src/asm/Instruction.go
@@ -4,6 +4,12 @@ import "git.urbach.dev/cli/q/src/cpu"
 
 type Instruction interface{}
 
+type AddRegisterRegister struct {
+	Destination cpu.Register
+	Source      cpu.Register
+	Operand     cpu.Register
+}
+
 type AndRegisterNumber struct {
 	Destination cpu.Register
 	Source      cpu.Register
diff --git a/src/asm/compilerARM.go b/src/asm/compilerARM.go
index 46d3462..c6604c8 100644
--- a/src/asm/compilerARM.go
+++ b/src/asm/compilerARM.go
@@ -16,6 +16,8 @@ func (c *compiler) append(code uint32) {
 
 func (c *compilerARM) Compile(instr Instruction) {
 	switch instr := instr.(type) {
+	case *AddRegisterRegister:
+		c.append(arm.AddRegisterRegister(instr.Destination, instr.Source, instr.Operand))
 	case *Call:
 		start := len(c.code)
 		c.append(arm.Call(0))
diff --git a/src/asm/compilerX86.go b/src/asm/compilerX86.go
index 1eb7a10..61977f4 100644
--- a/src/asm/compilerX86.go
+++ b/src/asm/compilerX86.go
@@ -14,18 +14,18 @@ type compilerX86 struct {
 
 func (c *compilerX86) Compile(instr Instruction) {
 	switch instr := instr.(type) {
+	case *AddRegisterRegister:
+		if instr.Destination != instr.Source {
+			c.code = x86.MoveRegisterRegister(c.code, instr.Destination, instr.Source)
+		}
+
+		c.code = x86.AddRegisterRegister(c.code, instr.Destination, instr.Operand)
 	case *AndRegisterNumber:
 		if instr.Destination != instr.Source {
 			c.code = x86.MoveRegisterRegister(c.code, instr.Destination, instr.Source)
 		}
 
 		c.code = x86.AndRegisterNumber(c.code, instr.Destination, instr.Number)
-	case *SubRegisterNumber:
-		if instr.Destination != instr.Source {
-			c.code = x86.MoveRegisterRegister(c.code, instr.Destination, instr.Source)
-		}
-
-		c.code = x86.SubRegisterNumber(c.code, instr.Destination, instr.Number)
 	case *Call:
 		c.code = x86.Call(c.code, 0)
 		end := len(c.code)
@@ -102,6 +102,12 @@ func (c *compilerX86) Compile(instr Instruction) {
 		c.code = x86.MoveRegisterRegister(c.code, instr.Destination, instr.Source)
 	case *Return:
 		c.code = x86.Return(c.code)
+	case *SubRegisterNumber:
+		if instr.Destination != instr.Source {
+			c.code = x86.MoveRegisterRegister(c.code, instr.Destination, instr.Source)
+		}
+
+		c.code = x86.SubRegisterNumber(c.code, instr.Destination, instr.Number)
 	case *Syscall:
 		c.code = x86.Syscall(c.code)
 	default:
diff --git a/src/core/Evaluate.go b/src/core/Evaluate.go
index 1af8a0f..2e75bd1 100644
--- a/src/core/Evaluate.go
+++ b/src/core/Evaluate.go
@@ -211,6 +211,32 @@ func (f *Function) Evaluate(expr *expression.Expression) (ssa.Value, error) {
 		return nil, errors.New(&UnknownIdentifier{Name: label}, f.File, left.Token.Position)
 
 	default:
+		if expr.Token.IsOperator() {
+			left := expr.Children[0]
+			right := expr.Children[1]
+
+			leftValue, err := f.Evaluate(left)
+
+			if err != nil {
+				return nil, err
+			}
+
+			rightValue, err := f.Evaluate(right)
+
+			if err != nil {
+				return nil, err
+			}
+
+			v := f.Append(&ssa.BinaryOp{
+				Left:   leftValue,
+				Right:  rightValue,
+				Op:     expr.Token.Kind,
+				Source: ssa.Source(expr.Source),
+			})
+
+			return v, nil
+		}
+
 		panic("not implemented")
 	}
 }
\ No newline at end of file
diff --git a/src/ssa2asm/ValueToRegister.go b/src/ssa2asm/ValueToRegister.go
index 850074d..89c4d51 100644
--- a/src/ssa2asm/ValueToRegister.go
+++ b/src/ssa2asm/ValueToRegister.go
@@ -12,6 +12,16 @@ import (
 // ValueToRegister moves a value into the given `destination` register.
 func (f *Compiler) ValueToRegister(instr ssa.Value, destination cpu.Register) {
 	switch instr := instr.(type) {
+	case *ssa.BinaryOp:
+		f.ValueToRegister(instr.Left, destination)
+		f.ValueToRegister(instr.Right, 7)
+
+		f.Assembler.Append(&asm.AddRegisterRegister{
+			Destination: destination,
+			Source:      destination,
+			Operand:     7,
+		})
+
 	case *ssa.Bytes:
 		f.Count.Data++
 		label := f.CreateLabel("data", f.Count.Data)
diff --git a/tests/sum.q b/tests/sum.q
new file mode 100644
index 0000000..abd95d6
--- /dev/null
+++ b/tests/sum.q
@@ -0,0 +1,10 @@
+main() {
+	t1 := sum(1, 2)
+	t2 := sum(3, 4)
+	t3 := sum(t1, t2)
+	syscall(60, t3)
+}
+
+sum(a int, b int) -> int {
+	return a + b
+}
\ No newline at end of file