JVM IR: Fix mangling for suspend functions with inline class params (KT-41374)

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')

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;

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");

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");