Improved code generation

tests/programs/return.q

@@ -0,0 +1,11 @@
+main() {
+	syscall(60, f(2))
+}
+
+f(x) {
+	return x + 1 + g(x)
+}
+
+g(x) {
+	return x + 1
+}

tests/programs_test.go

@@ -20,6 +20,7 @@ var programs = []struct {
 	{"square-sum.q", "", 25},
 	{"chained-calls.q", "", 9},
 	{"nested-calls.q", "", 4},
+	{"return.q", "", 6},
 }
 
 func TestPrograms(t *testing.T) {