IR to CFG: function generator (initial version)

compiler/ir/ir.ir2cfg/src/org/jetbrains/kotlin/ir2cfg/generators/FunctionGenerator.kt

@@ -0,0 +1,109 @@
+/*
+ * 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.ir2cfg.generators
+
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.declarations.IrFunction
+import org.jetbrains.kotlin.ir.declarations.IrVariable
+import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
+import org.jetbrains.kotlin.ir2cfg.graph.ControlFlowGraph
+import org.jetbrains.kotlin.ir2cfg.nodes.MergeCfgElement
+
+class FunctionGenerator(val function: IrFunction) {
+
+    val builder = FunctionBuilder(function)
+
+    val exit = MergeCfgElement(function, "Function exit")
+
+    fun generate(): ControlFlowGraph {
+        val visitor = FunctionVisitor()
+        function.accept(visitor, true)
+        return builder.build()
+    }
+
+    inner class FunctionVisitor : IrElementVisitor<IrElement?, Boolean> {
+
+        inline fun <reified IE : IrElement> IE.process(includeSelf: Boolean = true) = this.accept(this@FunctionVisitor, includeSelf)
+
+        override fun visitFunction(declaration: IrFunction, data: Boolean): IrElement? {
+            if (data) {
+                builder.add(declaration)
+            }
+            val result = declaration.body?.process()
+            if (result != null && !result.isNothing()) {
+                builder.jump(exit, from = result)
+            }
+            return result
+        }
+
+        private fun IrStatementContainer.process(): IrElement? {
+            var result: IrElement? = null
+            for (statement in statements) {
+                result = statement.process()
+            }
+            return result
+        }
+
+        private fun IrElement?.isNothing() = this is IrExpression && KotlinBuiltIns.isNothing(type)
+
+        override fun visitBlockBody(body: IrBlockBody, data: Boolean): IrElement? {
+            return body.process() ?: body
+        }
+
+        override fun visitBlock(expression: IrBlock, data: Boolean): IrElement? {
+            return expression.process() ?: expression
+        }
+
+        override fun visitVariable(declaration: IrVariable, data: Boolean): IrElement? {
+            declaration.initializer?.process()
+            return if (data) {
+                builder.add(declaration)
+                declaration
+            }
+            else null
+        }
+
+        override fun visitReturn(expression: IrReturn, data: Boolean): IrElement? {
+            expression.value.process()
+            if (data) {
+                builder.add(expression)
+            }
+            builder.jump(exit)
+            return expression
+        }
+
+        override fun visitExpressionBody(body: IrExpressionBody, data: Boolean): IrElement? {
+            if (data) {
+                builder.add(body)
+            }
+            return body.expression.process()
+        }
+
+        override fun visitExpression(expression: IrExpression, data: Boolean): IrElement? {
+            if (data) {
+                builder.add(expression)
+            }
+            return expression
+        }
+
+        override fun visitElement(element: IrElement, data: Boolean): IrElement? {
+            TODO("not implemented")
+        }
+    }
+}

compiler/ir/ir.ir2cfg/src/org/jetbrains/kotlin/ir2cfg/nodes/CfgIrElement.kt

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+/*
+ * 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.ir2cfg.nodes
+
+import org.jetbrains.kotlin.ir.IrElement
+
+interface CfgIrElement : IrElement

compiler/ir/ir.ir2cfg/src/org/jetbrains/kotlin/ir2cfg/nodes/MergeCfgElement.kt

@@ -0,0 +1,35 @@
+/*
+ * 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.ir2cfg.nodes
+
+import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.util.dump
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
+
+class MergeCfgElement(val from: IrElement, val name: String) : CfgIrElement {
+    override val startOffset = from.startOffset
+    override val endOffset = from.endOffset
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D) = visitor.visitElement(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) = Unit
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) = Unit
+
+    override fun toString() = "$name: ${from.dump()}"
+}