org.jetbrains.kotlin.js.inline.clean.CoroutineStateElimination.kt Maven / Gradle / Ivy
/*
* Copyright 2010-2016 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jetbrains.kotlin.js.inline.clean
import org.jetbrains.kotlin.js.backend.ast.*
import org.jetbrains.kotlin.js.coroutine.finallyPath
import org.jetbrains.kotlin.js.coroutine.targetBlock
import org.jetbrains.kotlin.js.coroutine.targetExceptionBlock
class CoroutineStateElimination(private val body: JsBlock) {
fun apply(): Boolean {
var changed = false
body.accept(object : RecursiveJsVisitor() {
override fun visitBlock(x: JsBlock) {
visitStatements(x.statements)
super.visitBlock(x)
}
override fun visitCase(x: JsCase) {
visitStatements(x.statements)
super.visitCase(x)
}
private fun visitStatements(statements: MutableList) {
class IndexHolder {
var value: Int? = null
}
val indexesToRemove = mutableSetOf()
val lastTargetBlockIndex = IndexHolder()
val lastTargetExceptionBlockIndex = IndexHolder()
val lastFinallyPathIndex = IndexHolder()
for ((index, statement) in statements.withIndex()) {
val indexesToUpdate = mutableListOf()
if (statement is JsExpressionStatement) {
if (statement.targetBlock) {
indexesToUpdate += lastTargetBlockIndex
}
if (statement.targetExceptionBlock) {
indexesToUpdate += lastTargetExceptionBlockIndex
}
if (statement.finallyPath) {
indexesToUpdate += lastFinallyPathIndex
}
}
if (indexesToUpdate.isNotEmpty()) {
for (indexToUpdate in indexesToUpdate) {
indexToUpdate.value?.let { indexesToRemove += it }
indexToUpdate.value = index
}
}
else {
lastTargetBlockIndex.value = null
lastTargetExceptionBlockIndex.value = null
lastFinallyPathIndex.value = null
}
}
for (index in indexesToRemove.sorted().reversed()) {
statements.removeAt(index)
}
if (indexesToRemove.isNotEmpty()) {
changed = true
}
}
})
return changed
}
}