[JS IR] Keep box and unbox intrinsics in call args after decomposing

^KT-59717 Fixed

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIrBackendContext.kt

@@ -97,7 +97,9 @@ class JsIrBackendContext(
     override fun isSideEffectFree(call: IrCall): Boolean =
         call.symbol in intrinsics.primitiveToLiteralConstructor.values ||
                 call.symbol == intrinsics.arrayLiteral ||
-                call.symbol == intrinsics.arrayConcat
+                call.symbol == intrinsics.arrayConcat ||
+                call.symbol == intrinsics.jsBoxIntrinsic ||
+                call.symbol == intrinsics.jsUnboxIntrinsic
 
     val devMode = configuration[JSConfigurationKeys.DEVELOPER_MODE] ?: false
     val errorPolicy = configuration[JSConfigurationKeys.ERROR_TOLERANCE_POLICY] ?: ErrorTolerancePolicy.DEFAULT

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/BlockDecomposerLowering.kt

@@ -16,6 +16,7 @@ import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.backend.js.JsCommonBackendContext
 import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
 import org.jetbrains.kotlin.ir.backend.js.ir.JsIrBuilder
+import org.jetbrains.kotlin.ir.backend.js.utils.typeArguments
 import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
@@ -94,7 +95,7 @@ abstract class AbstractBlockDecomposerLowering(private val context: JsCommonBack
 }
 
 class BlockDecomposerTransformer(
-    private val context: CommonBackendContext,
+    private val context: JsCommonBackendContext,
     private val unreachableExpression: () -> IrExpression
 ) : IrElementTransformerVoid() {
     private lateinit var function: IrDeclarationParent
@@ -111,6 +112,9 @@ class BlockDecomposerTransformer(
 
     private val booleanNotSymbol = context.irBuiltIns.booleanNotSymbol
 
+    private val boxIntrinsic = context.inlineClassesUtils.boxIntrinsic
+    private val unboxIntrinsic = context.inlineClassesUtils.unboxIntrinsic
+
     override fun visitScript(declaration: IrScript): IrStatement {
         function = declaration
 
@@ -537,9 +541,9 @@ class BlockDecomposerTransformer(
                     value.isPure(anyVariable = false, context = context) -> value
                     else -> {
                         // TODO: do not wrap if value is pure (const, variable, etc)
-                        val irVar = makeTempVar(value.type, value)
-                        newStatements += irVar
-                        JsIrBuilder.buildGetValue(irVar.symbol)
+                        val (newArg, tempVar) = mapArgument(value)
+                        newStatements += tempVar
+                        newArg
                     }
                 }
 
@@ -548,6 +552,42 @@ class BlockDecomposerTransformer(
             return arguments
         }
 
+        /**
+         * Move the passing argument and store it in a temporary variable.
+         * However, the box and unbox intrinsics should be preserved in the call.
+         * They can be used later for optimizations, for example, in [EqualityAndComparisonCallsTransformer].
+         * Example:
+         *      foo(boxIntrinsic(<expr>))
+         * should be transformed to:
+         *      var tmp = <expr>
+         *      foo(boxIntrinsic(tmp))
+         */
+        private fun mapArgument(arg: IrExpression): Pair<IrExpression, IrVariable> {
+            var saveToTmp = arg
+            var rootIntrinsicCall: IrCall? = null
+            var lastIntrinsicCall: IrCall? = null
+            while (saveToTmp is IrCall && (saveToTmp.symbol == boxIntrinsic || saveToTmp.symbol == unboxIntrinsic)) {
+                if (lastIntrinsicCall == null) {
+                    lastIntrinsicCall = JsIrBuilder.buildCall(saveToTmp.symbol, saveToTmp.type, saveToTmp.typeArguments.filterNotNull())
+                    rootIntrinsicCall = lastIntrinsicCall
+                } else {
+                    val nextCall = JsIrBuilder.buildCall(saveToTmp.symbol)
+                    lastIntrinsicCall.putValueArgument(0, nextCall)
+                    lastIntrinsicCall = nextCall
+                }
+                saveToTmp = saveToTmp.getValueArgument(0) ?: error("expect passing 1 argument to boxing intrinsic")
+            }
+
+            val irTempVar = makeTempVar(saveToTmp.type, saveToTmp)
+            val irGetTempVar = JsIrBuilder.buildGetValue(irTempVar.symbol)
+            val newArg = lastIntrinsicCall?.let {
+                it.putValueArgument(0, irGetTempVar)
+                rootIntrinsicCall
+            } ?: irGetTempVar
+
+            return newArg to irTempVar
+        }
+
         // TODO: remove this when vararg is lowered
         override fun visitVararg(expression: IrVararg): IrExpression {
             expression.transformChildrenVoid(expressionTransformer)

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsBoxTestGenerated.java

@@ -246,6 +246,12 @@ public class FirJsBoxTestGenerated extends AbstractFirJsBoxTest {
             runTest("js/js.translator/testData/box/char/charIsCheck.kt");
         }
 
+        @Test
+        @TestMetadata("charNoBoxing.kt")
+        public void testCharNoBoxing() throws Exception {
+            runTest("js/js.translator/testData/box/char/charNoBoxing.kt");
+        }
+
         @Test
         @TestMetadata("charRanges.kt")
         public void testCharRanges() throws Exception {

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsES6TestGenerated.java

@@ -246,6 +246,12 @@ public class IrBoxJsES6TestGenerated extends AbstractIrBoxJsES6Test {
             runTest("js/js.translator/testData/box/char/charIsCheck.kt");
         }
 
+        @Test
+        @TestMetadata("charNoBoxing.kt")
+        public void testCharNoBoxing() throws Exception {
+            runTest("js/js.translator/testData/box/char/charNoBoxing.kt");
+        }
+
         @Test
         @TestMetadata("charRanges.kt")
         public void testCharRanges() throws Exception {

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsTestGenerated.java

@@ -246,6 +246,12 @@ public class IrBoxJsTestGenerated extends AbstractIrBoxJsTest {
             runTest("js/js.translator/testData/box/char/charIsCheck.kt");
         }
 
+        @Test
+        @TestMetadata("charNoBoxing.kt")
+        public void testCharNoBoxing() throws Exception {
+            runTest("js/js.translator/testData/box/char/charNoBoxing.kt");
+        }
+
         @Test
         @TestMetadata("charRanges.kt")
         public void testCharRanges() throws Exception {

js/js.translator/testData/box/char/charNoBoxing.kt

@@ -0,0 +1,42 @@
+fun getC(c: Char) = c
+inline fun getCInline(c: Char) = c
+
+// CHECK_NEW_COUNT: function=testNonInline1 count=0
+fun testNonInline1(a: Char, b: Char) : Boolean {
+    return getC(a) == getC(b)
+}
+
+// CHECK_NEW_COUNT: function=testNonInline2 count=0
+fun testNonInline2(a: Char, b: Char) : Boolean {
+    val a1 = getC(a)
+    val b1 = getC(b)
+    return a1 == b1
+}
+
+// CHECK_NEW_COUNT: function=testInline1 count=0
+fun testInline1(a: Char, b: Char) : Boolean {
+    return getCInline(a) == getCInline(b)
+}
+
+// CHECK_NEW_COUNT: function=testInline2 count=0
+fun testInline2(a: Char, b: Char) : Boolean {
+    val a1 = getCInline(a)
+    val b1 = getCInline(b)
+    return a1 == b1
+}
+
+fun box(): String {
+    if (!testNonInline1('a', 'a')) {
+        return "Fail testNonInline1"
+    }
+    if (!testNonInline2('b', 'b')) {
+        return "Fail testNonInline2"
+    }
+    if (!testInline1('c', 'c')) {
+        return "Fail testInline1"
+    }
+    if (!testInline2('d', 'd')) {
+        return "Fail testInline2"
+    }
+    return "OK"
+}

js/js.translator/testData/box/inline/inlineClassEquals.kt

@@ -141,8 +141,8 @@ fun testUnderlyingInline() {
     }
     caseJsEq()
 
-    // CHECK_CALLED_IN_SCOPE: scope=testUnderlyingInline$caseEquals function=equals
-    // CHECK_NEW_COUNT: function=testUnderlyingInline$caseEquals count=4
+    // CHECK_NOT_CALLED_IN_SCOPE: scope=testUnderlyingInline$caseEquals function=equals
+    // CHECK_NEW_COUNT: function=testUnderlyingInline$caseEquals count=2
     fun caseEquals() {
         assertTrue(c1_1 == ClassUnderlayingInline(x1!!))
         assertTrue(ClassUnderlayingInline(x1!!) == c1_2)
@@ -256,8 +256,8 @@ fun testNullableUnderlyingInlineClass() {
     }
     caseJsEq()
 
-    // CHECK_CALLED_IN_SCOPE: scope=testNullableUnderlyingInlineClass$caseEquals function=equals
-    // CHECK_NEW_COUNT: function=testNullableUnderlyingInlineClass$caseEquals count=3
+    // CHECK_NOT_CALLED_IN_SCOPE: scope=testNullableUnderlyingInlineClass$caseEquals function=equals
+    // CHECK_NEW_COUNT: function=testNullableUnderlyingInlineClass$caseEquals count=1
     fun caseEquals() {
         assertTrue(ClassNullableUnderlayingInline(i1_1) == ClassNullableUnderlayingInline(i1_2!!))
     }
@@ -265,7 +265,7 @@ fun testNullableUnderlyingInlineClass() {
 }
 
 // CHECK_CALLED_IN_SCOPE: scope=testInlineClassWithInterface function=equals
-// CHECK_NEW_COUNT: function=testInlineClassWithInterface count=14
+// CHECK_NEW_COUNT: function=testInlineClassWithInterface count=10
 fun testInlineClassWithInterface() {
     val xi_1_1: InterfaceForInlineClass = ClassIntWithInterface(1)
     val xi_1_2: InterfaceForInlineClass = ClassIntWithInterface(1)