JVM_IR KT-42010 use IINC for postfix int increment/decrement

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBytecodeTextTestGenerated.java

@@ -3941,6 +3941,12 @@ public class FirBytecodeTextTestGenerated extends AbstractFirBytecodeTextTest {
         public void testJavaPrimitiveType() throws Exception {
             runTest("compiler/testData/codegen/bytecodeText/intrinsics/javaPrimitiveType.kt");
         }
+
+        @Test
+        @TestMetadata("postfixIncrDecr.kt")
+        public void testPostfixIncrDecr() throws Exception {
+            runTest("compiler/testData/codegen/bytecodeText/intrinsics/postfixIncrDecr.kt");
+        }
     }
 
     @Nested

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmSymbols.kt

@@ -811,7 +811,6 @@ class JvmSymbols(
         addFunction("equals", irBuiltIns.booleanType, isStatic = true).apply {
             addValueParameter("a", arrayType)
             addValueParameter("b", arrayType)
-
         }
     }
 
@@ -856,6 +855,19 @@ class JvmSymbols(
     val remainderUnsignedLong: IrSimpleFunctionSymbol = javaLangLong.functionByName("remainderUnsigned")
     val toUnsignedStringLong: IrSimpleFunctionSymbol = javaLangLong.functionByName("toUnsignedString")
 
+    val intPostfixIncr = createPostfixIncrDecrFun("<int++>", irBuiltIns.intType)
+    val intPostfixDecr = createPostfixIncrDecrFun("<int-->", irBuiltIns.intType)
+
+    private fun createPostfixIncrDecrFun(intrinsicName: String, type: IrType): IrSimpleFunctionSymbol =
+        irFactory.buildFun {
+            name = Name.special(intrinsicName)
+            origin = IrDeclarationOrigin.IR_BUILTINS_STUB
+        }.apply {
+            parent = kotlinJvmInternalPackage
+            addValueParameter("value", type)
+            returnType = type
+        }.symbol
+
     private fun createJavaPrimitiveClass(fqName: FqName, type: IrType): IrClassSymbol = createClass(fqName) { klass ->
         klass.addFunction("compareUnsigned", irBuiltIns.intType, isStatic = true).apply {
             addValueParameter("x", type)

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/intrinsics/IrIntrinsicMethods.kt

@@ -87,7 +87,9 @@ class IrIntrinsicMethods(val irBuiltIns: IrBuiltIns, val symbols: JvmSymbols) {
                 symbols.throwTypeCastException.toKey()!! to ThrowException(Type.getObjectType("kotlin/TypeCastException")),
                 symbols.throwUnsupportedOperationException.toKey()!! to ThrowException(Type.getObjectType("java/lang/UnsupportedOperationException")),
                 symbols.throwKotlinNothingValueException.toKey()!! to ThrowKotlinNothingValueException,
-                symbols.jvmIndyIntrinsic.toKey()!! to JvmInvokeDynamic
+                symbols.jvmIndyIntrinsic.toKey()!! to JvmInvokeDynamic,
+                symbols.intPostfixIncr.toKey()!! to PostfixIinc(1),
+                symbols.intPostfixDecr.toKey()!! to PostfixIinc(-1)
             ) +
                     numberConversionMethods() +
                     unaryFunForPrimitives("plus", UnaryPlus) +

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/intrinsics/PostfixIinc.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.backend.jvm.intrinsics
+
+import org.jetbrains.kotlin.backend.jvm.codegen.*
+import org.jetbrains.kotlin.ir.expressions.IrFunctionAccessExpression
+import org.jetbrains.kotlin.ir.expressions.IrGetValue
+import org.jetbrains.kotlin.ir.util.dump
+import org.jetbrains.kotlin.ir.util.render
+import org.jetbrains.org.objectweb.asm.Type
+
+class PostfixIinc(private val delta: Int) : IntrinsicMethod() {
+    override fun invoke(expression: IrFunctionAccessExpression, codegen: ExpressionCodegen, data: BlockInfo): PromisedValue? {
+        val argument = expression.getValueArgument(0) as? IrGetValue
+            ?: error("IrGetValue expected: ${expression.dump()}")
+        val varIndex = codegen.frameMap.getIndex(argument.symbol)
+        if (varIndex == -1)
+            error("Unmapped variable: ${argument.render()}")
+        argument.accept(codegen, data).materialize()
+        codegen.mv.iinc(varIndex, delta)
+        return MaterialValue(codegen, Type.INT_TYPE, argument.type)
+    }
+}

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmOptimizationLowering.kt

@@ -25,6 +25,7 @@ import org.jetbrains.kotlin.ir.symbols.impl.IrPublicSymbolBase
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.util.OperatorNameConventions
 
 internal val jvmOptimizationLoweringPhase = makeIrFilePhase(
     ::JvmOptimizationLowering,
@@ -405,11 +406,47 @@ class JvmOptimizationLowering(val context: JvmBackendContext) : FileLoweringPass
                 }
             }
 
+            if (expression.origin == IrStatementOrigin.POSTFIX_DECR || expression.origin == IrStatementOrigin.POSTFIX_INCR) {
+                expression.rewritePostfixIncrDecr()?.let { return it }
+            }
+
             expression.transformChildren(this, data)
             removeUnnecessaryTemporaryVariables(expression.statements)
             return expression
         }
 
+        private fun IrContainerExpression.rewritePostfixIncrDecr(): IrCall? {
+            return when (origin) {
+                IrStatementOrigin.POSTFIX_INCR, IrStatementOrigin.POSTFIX_DECR -> {
+                    val tmpVar = this.statements[0] as? IrVariable ?: return null
+                    val getIncrVar = tmpVar.initializer as? IrGetValue ?: return null
+                    if (!getIncrVar.type.isInt()) return null
+
+                    val setVar = this.statements[1] as? IrSetValue ?: return null
+                    if (setVar.symbol != getIncrVar.symbol) return null
+                    val setVarValue = setVar.value as? IrCall ?: return null
+                    val calleeName = setVarValue.symbol.owner.name
+                    if (calleeName != OperatorNameConventions.INC && calleeName != OperatorNameConventions.DEC) return null
+                    val calleeArg = setVarValue.dispatchReceiver as? IrGetValue ?: return null
+                    if (calleeArg.symbol != tmpVar.symbol) return null
+
+                    val getTmpVar = this.statements[2] as? IrGetValue ?: return null
+                    if (getTmpVar.symbol != tmpVar.symbol) return null
+
+                    val intrinsicSymbol =
+                        if (calleeName == OperatorNameConventions.INC)
+                            context.ir.symbols.intPostfixIncr
+                        else
+                            context.ir.symbols.intPostfixDecr
+
+                    return IrCallImpl.fromSymbolOwner(this.startOffset, this.endOffset, intrinsicSymbol)
+                        .apply { putValueArgument(0, getIncrVar) }
+                }
+                else ->
+                    null
+            }
+        }
+
         override fun visitGetValue(expression: IrGetValue, data: IrClass?): IrExpression {
             // Replace IrGetValue of an immutable temporary variable with a constant
             // initializer with the constant initializer.

compiler/testData/codegen/bytecodeText/intrinsics/postfixIncrDecr.kt

@@ -0,0 +1,34 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+
+fun use(i: Int) {}
+
+fun testPostfixIncr0() {
+    var k = 0
+    k++
+    use(k)
+}
+
+fun testPostfixIncr1() {
+    var k = 0
+    val t = k++
+    use(k)
+    use(t)
+}
+
+fun testPostfixDecr0() {
+    var k = 0
+    k--
+    use(k)
+}
+
+fun testPostfixDecr1() {
+    var k = 0
+    val t = k--
+    use(k)
+    use(t)
+}
+
+// 6 ISTORE
+// 8 ILOAD
+// 0 ICONST_1
+// 4 IINC

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/BytecodeTextTestGenerated.java

@@ -3797,6 +3797,12 @@ public class BytecodeTextTestGenerated extends AbstractBytecodeTextTest {
         public void testJavaPrimitiveType() throws Exception {
             runTest("compiler/testData/codegen/bytecodeText/intrinsics/javaPrimitiveType.kt");
         }
+
+        @Test
+        @TestMetadata("postfixIncrDecr.kt")
+        public void testPostfixIncrDecr() throws Exception {
+            runTest("compiler/testData/codegen/bytecodeText/intrinsics/postfixIncrDecr.kt");
+        }
     }
 
     @Nested

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBytecodeTextTestGenerated.java

@@ -3941,6 +3941,12 @@ public class IrBytecodeTextTestGenerated extends AbstractIrBytecodeTextTest {
         public void testJavaPrimitiveType() throws Exception {
             runTest("compiler/testData/codegen/bytecodeText/intrinsics/javaPrimitiveType.kt");
         }
+
+        @Test
+        @TestMetadata("postfixIncrDecr.kt")
+        public void testPostfixIncrDecr() throws Exception {
+            runTest("compiler/testData/codegen/bytecodeText/intrinsics/postfixIncrDecr.kt");
+        }
     }
 
     @Nested