From 24fcadb869fb38a638de40acad281d242090a28c Mon Sep 17 00:00:00 2001
From: Dmitry Petrov <dmitry.petrov@jetbrains.com>
Date: Wed, 7 Jul 2021 20:45:15 +0300
Subject: [PATCH] JVM don't run CCE on methods without optimizable conditional
 jumps

---
 ...nstantConditionEliminationMethodTransformer.kt | 15 +++++++++++++++
 .../testData/debug/stepping/tryCatchExpression.kt | 12 ------------
 .../testData/debug/stepping/tryCatchFinally.kt    | 12 ------------
 compiler/testData/debug/stepping/tryFinally.kt    |  9 ++++-----
 4 files changed, 19 insertions(+), 29 deletions(-)

diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/ConstantConditionEliminationMethodTransformer.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/ConstantConditionEliminationMethodTransformer.kt
index 92724b54ba8..20eb4f0f199 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/ConstantConditionEliminationMethodTransformer.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/ConstantConditionEliminationMethodTransformer.kt
@@ -34,11 +34,26 @@ import org.jetbrains.org.objectweb.asm.tree.analysis.Frame
 class ConstantConditionEliminationMethodTransformer : MethodTransformer() {
 
     override fun transform(internalClassName: String, methodNode: MethodNode) {
+        if (!methodNode.hasOptimizableConditions()) {
+            return
+        }
         do {
             val changes = ConstantConditionsOptimization(internalClassName, methodNode).run()
         } while (changes)
     }
 
+    private fun MethodNode.hasOptimizableConditions(): Boolean {
+        val insns = instructions.toArray()
+        return insns.any { it.isIntJump() } && insns.any { it.isIntConst() }
+    }
+
+    private fun AbstractInsnNode.isIntConst() =
+        opcode in Opcodes.ICONST_M1..Opcodes.ICONST_5 || opcode == Opcodes.BIPUSH || opcode == Opcodes.SIPUSH ||
+                (opcode == Opcodes.LDC && this is LdcInsnNode && cst is Int)
+
+    private fun AbstractInsnNode.isIntJump() =
+        opcode in Opcodes.IFEQ..Opcodes.IFLE || opcode in Opcodes.IF_ICMPEQ..Opcodes.IF_ICMPLE
+
     private class ConstantConditionsOptimization(val internalClassName: String, val methodNode: MethodNode) {
         fun run(): Boolean {
             val actions = collectRewriteActions()
diff --git a/compiler/testData/debug/stepping/tryCatchExpression.kt b/compiler/testData/debug/stepping/tryCatchExpression.kt
index caab3022a6a..ef39533b0f2 100644
--- a/compiler/testData/debug/stepping/tryCatchExpression.kt
+++ b/compiler/testData/debug/stepping/tryCatchExpression.kt
@@ -59,21 +59,13 @@ fun box() {
 // test.kt:32 mightThrow2
 // test.kt:33 mightThrow2
 // test.kt:11 foo
-// LINENUMBERS JVM_IR
 // test.kt:10 foo
-// LINENUMBERS JVM
-// test.kt:13 foo
-// LINENUMBERS
 // test.kt:16 foo
 // test.kt:17 foo
 // test.kt:36 mightThrow3
 // test.kt:37 mightThrow3
 // test.kt:17 foo
-// LINENUMBERS JVM_IR
 // test.kt:16 foo
-// LINENUMBERS JVM
-// test.kt:19 foo
-// LINENUMBERS
 // test.kt:21 foo
 // test.kt:42 box
 // test.kt:43 box
@@ -87,11 +79,7 @@ fun box() {
 // test.kt:32 mightThrow2
 // test.kt:33 mightThrow2
 // test.kt:11 foo
-// LINENUMBERS JVM
-// test.kt:13 foo
-// LINENUMBERS JVM_IR
 // test.kt:10 foo
-// LINENUMBERS
 // test.kt:16 foo
 // test.kt:17 foo
 // test.kt:36 mightThrow3
diff --git a/compiler/testData/debug/stepping/tryCatchFinally.kt b/compiler/testData/debug/stepping/tryCatchFinally.kt
index 21ae4d081ff..f71591017df 100644
--- a/compiler/testData/debug/stepping/tryCatchFinally.kt
+++ b/compiler/testData/debug/stepping/tryCatchFinally.kt
@@ -52,11 +52,7 @@ fun box() {
 // test.kt:13 foo
 // test.kt:17 foo
 // test.kt:18 foo
-// LINENUMBERS JVM
-// test.kt:17 foo
-// LINENUMBERS JVM_IR
 // test.kt:12 foo
-// LINENUMBERS
 // test.kt:19 foo
 // test.kt:34 box
 // test.kt:35 box
@@ -73,11 +69,7 @@ fun box() {
 // test.kt:15 foo
 // test.kt:17 foo
 // test.kt:18 foo
-// LINENUMBERS JVM
-// test.kt:17 foo
-// LINENUMBERS JVM_IR
 // test.kt:12 foo
-// LINENUMBERS
 // test.kt:19 foo
 // test.kt:36 box
 // test.kt:37 box
@@ -95,10 +87,6 @@ fun box() {
 // test.kt:15 foo
 // test.kt:17 foo
 // test.kt:18 foo
-// LINENUMBERS JVM
-// test.kt:17 foo
-// LINENUMBERS JVM_IR
 // test.kt:12 foo
-// LINENUMBERS
 // test.kt:19 foo
 // test.kt:38 box
\ No newline at end of file
diff --git a/compiler/testData/debug/stepping/tryFinally.kt b/compiler/testData/debug/stepping/tryFinally.kt
index 49a939cfdda..8f1137243bf 100644
--- a/compiler/testData/debug/stepping/tryFinally.kt
+++ b/compiler/testData/debug/stepping/tryFinally.kt
@@ -56,11 +56,7 @@ fun box() {
 // LINENUMBERS
 // test.kt:13 foo
 // test.kt:14 foo
-// LINENUMBERS JVM
-// test.kt:13 foo
-// LINENUMBERS JVM_IR
 // test.kt:10 foo
-// LINENUMBERS
 // test.kt:15 foo
 // test.kt:30 box
 // test.kt:31 box
@@ -74,4 +70,7 @@ fun box() {
 // test.kt:11 foo
 // test.kt:25 mightThrow2
 // test.kt:14 foo
-// test.kt:13 foo
+// LINENUMBERS JVM
+// test.kt:10 foo
+// LINENUMBERS JVM_IR
+// test.kt:13 foo
\ No newline at end of file