Files
kotlin-fork/compiler/testData/codegen/box/when/enumOptimization/kt14597.kt
T
Sergej Jaskiewicz 55ae6d1f3e [JS IR] Optimize pattern-matching of enums into comparing their ordinals
For this code:
```
enum class Season {
    WINTER,
    SPRING,
    SUMMER,
    AUTUMN
}

fun bar1(x : Season) : String {
    return when (x) {
        Season.WINTER, Season.SPRING -> "winter_spring"
        Season.SUMMER -> "summer"
        else -> "autumn"
    }
}
```

previously we generated this:
```
function foo(x) {
    var tmp0_subject = x;
    return (tmp0_subject.equals(Season_WINTER_getInstance())
        ? true
        : tmp0_subject.equals(Season_SPRING_getInstance()))
            ? 'winter_spring'
            : tmp0_subject.equals(Season_SUMMER_getInstance())
                ? 'summer'
                : 'autumn';
}
```

And now we generated this:
```
function bar2(x) {
  var tmp0_subject = x;
  var tmp0 = tmp0_subject._get_ordinal__0_k$();
  var tmp;
  switch (tmp0) {
    case 0:
    case 1:
      tmp = 'winter_spring';
      break;
    case 2:
      tmp = 'summer';
      break;
    case 3:
      tmp = 'autumn';
      break;
    default:
      noWhenBranchMatchedException();
      break;
  }
  return tmp;
}
```
2021-10-14 11:44:01 +00:00

25 lines
469 B
Kotlin
Vendored

// CHECK_CASES_COUNT: function=box count=6
// CHECK_IF_COUNT: function=box count=1
enum class En { A, B, C }
fun box(): String {
var res = ""
// nullable variable
val en2: Any? = En.A
if (en2 is En) {
when (en2) {
En.A -> {res += "O"}
En.B -> {}
En.C -> {}
}
when (en2 as En) {
En.A -> {res += "K"}
En.B -> {}
En.C -> {}
}
}
return res
}