From 78ab957bfe25b373a52f15802be5f18317f9f5d2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Steven=20Sch=C3=A4fer?= <stevenschaefer@google.com>
Date: Mon, 31 Aug 2020 14:59:44 +0200
Subject: [PATCH] JVM IR: Fix mangling for suspend functions with inline class
 params (KT-41374)

---
 .../jvm/lower/inlineclasses/InlineClassAbi.kt | 13 +++++++++++--
 .../inlineClasses/suspendFunctionMangling.kt  | 19 +++++++++++++++++++
 .../codegen/BytecodeTextTestGenerated.java    |  5 +++++
 .../ir/IrBytecodeTextTestGenerated.java       |  5 +++++
 4 files changed, 40 insertions(+), 2 deletions(-)
 create mode 100644 compiler/testData/codegen/bytecodeText/inlineClasses/suspendFunctionMangling.kt

diff --git a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/inlineclasses/InlineClassAbi.kt b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/inlineclasses/InlineClassAbi.kt
index 283edd93c3d..b4006b03595 100644
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/inlineclasses/InlineClassAbi.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/inlineclasses/InlineClassAbi.kt
@@ -100,8 +100,17 @@ object InlineClassAbi {
     fun returnHashSuffix(irFunction: IrFunction) =
         md5base64(":${irFunction.returnType.eraseToString()}")
 
-    private fun hashSuffix(irFunction: IrFunction) =
-        md5base64(irFunction.fullValueParameterList.joinToString { it.type.eraseToString() })
+    private fun hashSuffix(irFunction: IrFunction): String {
+        val signatureElementsForMangling =
+            irFunction.fullValueParameterList.mapTo(mutableListOf()) { it.type.eraseToString() }
+        if (irFunction.isSuspend) {
+            // The JVM backend computes mangled names after creating suspend function views, but before default argument
+            // stub insertion. It would be nice if this part of the continuation lowering happened earlier in the pipeline.
+            // TODO: Move suspend function view creation before JvmInlineClassLowering.
+            signatureElementsForMangling += "Lkotlin.coroutines.Continuation;"
+        }
+        return md5base64(signatureElementsForMangling.joinToString())
+    }
 
     private fun IrType.eraseToString() = buildString {
         append('L')
diff --git a/compiler/testData/codegen/bytecodeText/inlineClasses/suspendFunctionMangling.kt b/compiler/testData/codegen/bytecodeText/inlineClasses/suspendFunctionMangling.kt
new file mode 100644
index 00000000000..730fcca579d
--- /dev/null
+++ b/compiler/testData/codegen/bytecodeText/inlineClasses/suspendFunctionMangling.kt
@@ -0,0 +1,19 @@
+// KT-41374
+// !LANGUAGE: +InlineClasses
+// FILE: test.kt
+
+package a
+
+inline class P(val i: Int)
+
+suspend fun foo(p: P = P(1)) {}
+
+suspend fun bar(p: P) {}
+
+// The mangled name for a suspend function includes the continuation parameter in the hash computation, but not the
+// default argument mask and handler.
+
+// 1 public final static foo-zMJ7EWY\(ILkotlin/coroutines/Continuation;\)Ljava/lang/Object;
+// 1 public static synthetic foo-zMJ7EWY\$default\(ILkotlin/coroutines/Continuation;ILjava/lang/Object;\)Ljava/lang/Object;
+// 1 INVOKESTATIC a/TestKt.foo-zMJ7EWY \(ILkotlin/coroutines/Continuation;\)Ljava/lang/Object;
+// 1 public final static bar-zMJ7EWY\(ILkotlin/coroutines/Continuation;\)Ljava/lang/Object;
\ No newline at end of file
diff --git a/compiler/tests/org/jetbrains/kotlin/codegen/BytecodeTextTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/codegen/BytecodeTextTestGenerated.java
index b832243ea32..74027e3f652 100644
--- a/compiler/tests/org/jetbrains/kotlin/codegen/BytecodeTextTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/codegen/BytecodeTextTestGenerated.java
@@ -3157,6 +3157,11 @@ public class BytecodeTextTestGenerated extends AbstractBytecodeTextTest {
             runTest("compiler/testData/codegen/bytecodeText/inlineClasses/skipCallToUnderlyingValueOfInlineClass.kt");
         }
 
+        @TestMetadata("suspendFunctionMangling.kt")
+        public void testSuspendFunctionMangling() throws Exception {
+            runTest("compiler/testData/codegen/bytecodeText/inlineClasses/suspendFunctionMangling.kt");
+        }
+
         @TestMetadata("toStringIsCalledByInlineClass.kt")
         public void testToStringIsCalledByInlineClass() throws Exception {
             runTest("compiler/testData/codegen/bytecodeText/inlineClasses/toStringIsCalledByInlineClass.kt");
diff --git a/compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBytecodeTextTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBytecodeTextTestGenerated.java
index 239929bd763..57d45823a6a 100644
--- a/compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBytecodeTextTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBytecodeTextTestGenerated.java
@@ -3252,6 +3252,11 @@ public class IrBytecodeTextTestGenerated extends AbstractIrBytecodeTextTest {
             runTest("compiler/testData/codegen/bytecodeText/inlineClasses/skipCallToUnderlyingValueOfInlineClass.kt");
         }
 
+        @TestMetadata("suspendFunctionMangling.kt")
+        public void testSuspendFunctionMangling() throws Exception {
+            runTest("compiler/testData/codegen/bytecodeText/inlineClasses/suspendFunctionMangling.kt");
+        }
+
         @TestMetadata("toStringIsCalledByInlineClass.kt")
         public void testToStringIsCalledByInlineClass() throws Exception {
             runTest("compiler/testData/codegen/bytecodeText/inlineClasses/toStringIsCalledByInlineClass.kt");