From 32a94c70e9825b11ec38771f445af2808527da8e Mon Sep 17 00:00:00 2001
From: Ilmir Usmanov <ilmir.usmanov@jetbrains.com>
Date: Tue, 9 Jan 2018 19:19:27 +0300
Subject: [PATCH] Use tail call optimization if ARETURN has multiple sources

 #KT-21977: Fixed
---
 .../CoroutineTransformerMethodVisitor.kt      | 11 +++++-----
 .../bytecodeListing/tailCallIntrinsics.kt     | 18 +++++++++++++++++
 .../bytecodeListing/tailCallIntrinsics.txt    | 20 +++++++++++++++++++
 .../codegen/BytecodeListingTestGenerated.java |  6 ++++++
 4 files changed, 49 insertions(+), 6 deletions(-)
 create mode 100644 compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.kt
 create mode 100644 compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.txt

diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/coroutines/CoroutineTransformerMethodVisitor.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/coroutines/CoroutineTransformerMethodVisitor.kt
index c8364e88a5b..847a5a60739 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/coroutines/CoroutineTransformerMethodVisitor.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/coroutines/CoroutineTransformerMethodVisitor.kt
@@ -701,12 +701,11 @@ private fun allSuspensionPointsAreTailCalls(
         if (insideTryBlock) return@all false
 
         safelyReachableReturns[endIndex + 1]?.all { returnIndex ->
-            val sourceInsn =
-                    sourceFrames[returnIndex].top().sure {
-                        "There must be some value on stack to return"
-                    }.insns.singleOrNull()
-
-            sourceInsn?.let(instructions::indexOf) in beginIndex..endIndex
+            sourceFrames[returnIndex].top().sure {
+                "There must be some value on stack to return"
+            }.insns.all { sourceInsn ->
+                sourceInsn?.let(instructions::indexOf) in beginIndex..endIndex
+            }
         } ?: false
     }
 }
diff --git a/compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.kt b/compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.kt
new file mode 100644
index 00000000000..2db6f7e9522
--- /dev/null
+++ b/compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.kt
@@ -0,0 +1,18 @@
+// WITH_RUNTIME
+import kotlin.coroutines.experimental.*
+import kotlin.coroutines.experimental.intrinsics.*
+
+var p: Int = 5846814
+private suspend fun withoutInline() {
+    val c = { c: Continuation<Unit> ->
+        if (p > 52158) Unit else COROUTINE_SUSPENDED
+    }
+
+    return suspendCoroutineOrReturn(c)
+}
+
+private suspend fun withInline() {
+    return suspendCoroutineOrReturn { c ->
+        if (p > 52158) Unit else COROUTINE_SUSPENDED
+    }
+}
\ No newline at end of file
diff --git a/compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.txt b/compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.txt
new file mode 100644
index 00000000000..f9d255385e3
--- /dev/null
+++ b/compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.txt
@@ -0,0 +1,20 @@
+@kotlin.Metadata
+final class TailCallIntrinsicsKt$withoutInline$c$1 {
+    public final static field INSTANCE: TailCallIntrinsicsKt$withoutInline$c$1
+    inner class TailCallIntrinsicsKt$withoutInline$c$1
+    static method <clinit>(): void
+    method <init>(): void
+    public final @org.jetbrains.annotations.NotNull method invoke(@org.jetbrains.annotations.NotNull p0: kotlin.coroutines.experimental.Continuation): java.lang.Object
+    public synthetic method invoke(p0: java.lang.Object): java.lang.Object
+}
+
+@kotlin.Metadata
+public final class TailCallIntrinsicsKt {
+    private static field p: int
+    inner class TailCallIntrinsicsKt$withoutInline$c$1
+    static method <clinit>(): void
+    public final static method getP(): int
+    public final static method setP(p0: int): void
+    final static @org.jetbrains.annotations.Nullable method withInline(@org.jetbrains.annotations.NotNull p0: kotlin.coroutines.experimental.Continuation): java.lang.Object
+    final static @org.jetbrains.annotations.Nullable method withoutInline(@org.jetbrains.annotations.NotNull p0: kotlin.coroutines.experimental.Continuation): java.lang.Object
+}
diff --git a/compiler/tests/org/jetbrains/kotlin/codegen/BytecodeListingTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/codegen/BytecodeListingTestGenerated.java
index f3d8c381f3c..7d21f53917c 100644
--- a/compiler/tests/org/jetbrains/kotlin/codegen/BytecodeListingTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/codegen/BytecodeListingTestGenerated.java
@@ -151,6 +151,12 @@ public class BytecodeListingTestGenerated extends AbstractBytecodeListingTest {
         doTest(fileName);
     }
 
+    @TestMetadata("tailCallIntrinsics.kt")
+    public void testTailCallIntrinsics() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeListing/tailCallIntrinsics.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("tailSuspendUnitFun.kt")
     public void testTailSuspendUnitFun() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeListing/tailSuspendUnitFun.kt");