From 7e943ab757305bb8ad0a9d61060899cd10e4d407 Mon Sep 17 00:00:00 2001
From: Dmitry Petrov <dmitry.petrov@jetbrains.com>
Date: Mon, 23 Aug 2021 13:27:17 +0300
Subject: [PATCH] JVM don't optimize out starting ASTORE of TCB handler

---
 .../codegen/optimization/temporaryVals/TemporaryVals.kt   | 8 ++++++++
 .../coroutines/varValueConflictsWithTableSameSort.kt      | 4 +++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/temporaryVals/TemporaryVals.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/temporaryVals/TemporaryVals.kt
index bb358175814..269e35def71 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/temporaryVals/TemporaryVals.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/temporaryVals/TemporaryVals.kt
@@ -64,6 +64,14 @@ class TemporaryValsAnalyzer {
             }
         }
 
+        // Some coroutine transformations require exception handler to start from an ASTORE instruction.
+        for (tcb in methodNode.tryCatchBlocks) {
+            val handlerFirstInsn = tcb.handler.next ?: continue
+            if (handlerFirstInsn.opcode == Opcodes.ASTORE) {
+                potentiallyTemporaryStores.remove(handlerFirstInsn)
+            }
+        }
+
         // If the method is big, and we couldn't eliminate enough temporary variable store candidates,
         // bail out, treat all variables as non-temporary.
         // Here we estimate memory required to store all relevant information as O(N * M * K),
diff --git a/compiler/testData/codegen/bytecodeText/coroutines/varValueConflictsWithTableSameSort.kt b/compiler/testData/codegen/bytecodeText/coroutines/varValueConflictsWithTableSameSort.kt
index 5a0cfdb5d8b..98890b07764 100644
--- a/compiler/testData/codegen/bytecodeText/coroutines/varValueConflictsWithTableSameSort.kt
+++ b/compiler/testData/codegen/bytecodeText/coroutines/varValueConflictsWithTableSameSort.kt
@@ -43,6 +43,8 @@ fun box(): String {
 
 // 1 LOCALVARIABLE i Ljava/lang/String; L.* 3
 // 1 PUTFIELD VarValueConflictsWithTableSameSortKt\$box\$1.L\$0 : Ljava/lang/Object;
+/* 1 load in the catch (e: Throwable) { throw e } block which is implicitly wrapped around try/finally */
+// 1 ALOAD 3\s+ATHROW
 /* 1 load in result = s */
 // 1 ALOAD 3\s+PUTFIELD kotlin/jvm/internal/Ref\$ObjectRef\.element
 /* 1 load in spill */
@@ -50,7 +52,7 @@ fun box(): String {
 /* 2 loads in println(s) */
 // 2 ALOAD 3\s+INVOKEVIRTUAL java/io/PrintStream.println \(Ljava/lang/Object;\)V
 /* But no further load when spilling 's' to the continuation */
-// 4 ALOAD 3
+// 5 ALOAD 3
 
 // We merge LVT records for two consequent branches, but we split the local over the restore code.
 // JVM_IR_TEMPLATES