Implemented compilation to SSA form

src/cpu/Register.go

@@ -0,0 +1,11 @@
+package cpu
+
+import "fmt"
+
+// Register represents the number of the register.
+type Register uint8
+
+// String returns the human readable name of the register.
+func (r Register) String() string {
+	return fmt.Sprintf("r%d", r)
+}

src/cpu/Register_test.go

@@ -0,0 +1,13 @@
+package cpu_test
+
+import (
+	"testing"
+
+	"git.urbach.dev/cli/q/src/cpu"
+	"git.urbach.dev/go/assert"
+)
+
+func TestRegisterString(t *testing.T) {
+	register := cpu.Register(1)
+	assert.Equal(t, "r1", register.String())
+}