From b940418604424c0bb5dcf88726e0f879cdb49984 Mon Sep 17 00:00:00 2001
From: Alexander Udalov <Alexander.Udalov@jetbrains.com>
Date: Tue, 20 Nov 2018 19:28:02 +0100
Subject: [PATCH] Compute default method signature lazily in CallableMethod

To prevent calling mapDefaultMethod for methods which are guaranteed
not to have default parameters (e.g. signature-polymorphic methods)
---
 .../org/jetbrains/kotlin/codegen/CallableMethod.kt  |  5 +++--
 .../kotlin/codegen/state/KotlinTypeMapper.java      | 13 ++++++-------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/CallableMethod.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/CallableMethod.kt
index 732849c9393..01329466178 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/CallableMethod.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/CallableMethod.kt
@@ -21,7 +21,7 @@ import org.jetbrains.org.objectweb.asm.util.Printer
 class CallableMethod(
     override val owner: Type,
     private val defaultImplOwner: Type?,
-    private val defaultMethodDesc: String,
+    computeDefaultMethodDesc: () -> String,
     private val signature: JvmMethodSignature,
     private val invokeOpcode: Int,
     override val dispatchReceiverType: Type?,
@@ -33,6 +33,8 @@ class CallableMethod(
     private val isInterfaceMethod: Boolean = Opcodes.INVOKEINTERFACE == invokeOpcode,
     private val isDefaultMethodInInterface: Boolean = false
 ) : Callable {
+    private val defaultMethodDesc: String by lazy(LazyThreadSafetyMode.PUBLICATION, computeDefaultMethodDesc)
+
     fun getValueParameters(): List<JvmMethodParameterSignature> =
         signature.valueParameters
 
@@ -45,7 +47,6 @@ class CallableMethod(
     override val parameterTypes: Array<Type>
         get() = getAsmMethod().argumentTypes
 
-
     override fun genInvokeInstruction(v: InstructionAdapter) {
         v.visitMethodInsn(
             invokeOpcode,
diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java b/compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java
index 89f5bb2871f..666100be7b9 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java
@@ -797,10 +797,9 @@ public class KotlinTypeMapper {
             JvmMethodSignature method = mapSignatureSkipGeneric(descriptor.getOriginal());
             Type owner = mapOwner(descriptor);
             FunctionDescriptor originalDescriptor = descriptor.getOriginal();
-            String defaultImplDesc = mapDefaultMethod(originalDescriptor, OwnerKind.IMPLEMENTATION).getDescriptor();
             return new CallableMethod(
-                    owner, owner, defaultImplDesc, method, INVOKESPECIAL,
-                    null, null, null, null, null, originalDescriptor.getReturnType(), false, false
+                    owner, owner, () -> mapDefaultMethod(originalDescriptor, OwnerKind.IMPLEMENTATION).getDescriptor(), method,
+                    INVOKESPECIAL, null, null, null, null, null, originalDescriptor.getReturnType(), false, false
             );
         }
 
@@ -956,11 +955,11 @@ public class KotlinTypeMapper {
             receiverParameterType = null;
         }
 
-        String defaultImplDesc = mapDefaultMethod(baseMethodDescriptor, getKindForDefaultImplCall(baseMethodDescriptor)).getDescriptor();
-
         return new CallableMethod(
-                owner, ownerForDefaultImpl, defaultImplDesc, signature, invokeOpcode,
-                thisClass, dispatchReceiverKotlinType, receiverParameterType, extensionReceiverKotlinType, calleeType, returnKotlinType,
+                owner, ownerForDefaultImpl,
+                () -> mapDefaultMethod(baseMethodDescriptor, getKindForDefaultImplCall(baseMethodDescriptor)).getDescriptor(),
+                signature, invokeOpcode, thisClass, dispatchReceiverKotlinType, receiverParameterType, extensionReceiverKotlinType,
+                calleeType, returnKotlinType,
                 jvmTarget.compareTo(JvmTarget.JVM_1_8) >= 0 ? isInterfaceMember : invokeOpcode == INVOKEINTERFACE,
                 isDefaultMethodInInterface
         );