Improved code generation

tests/programs/exit.q

@@ -0,0 +1,11 @@
+main() {
+	exit(f(1) + f(2) + f(3))
+}
+
+exit(code) {
+	syscall(60, code)
+}
+
+f(x) {
+	return x + 1
+}

tests/programs_test.go

@@ -18,6 +18,15 @@ var programs = []struct {
 	{"empty.q", "", 0},
 	{"square-sum.q", "", 25},
 	{"multi-calls.q", "", 9},
+	{"exit.q", "", 9},
+}
+
+func TestPrograms(t *testing.T) {
+	for _, test := range programs {
+		t.Run(test.Name, func(t *testing.T) {
+			run(t, filepath.Join("programs", test.Name), test.ExpectedOutput, test.ExpectedExitCode)
+		})
+	}
 }
 
 func BenchmarkPrograms(b *testing.B) {
@@ -33,14 +42,6 @@ func BenchmarkPrograms(b *testing.B) {
 	}
 }
 
-func TestPrograms(t *testing.T) {
-	for _, test := range programs {
-		t.Run(test.Name, func(t *testing.T) {
-			run(t, filepath.Join("programs", test.Name), test.ExpectedOutput, test.ExpectedExitCode)
-		})
-	}
-}
-
 // run builds and runs the file to check if the output matches the expected output.
 func run(t *testing.T, name string, expectedOutput string, expectedExitCode int) {
 	b := build.New(name)