From d27ecca0e9ef94ad4c0aa4f144a4bf74636efd79 Mon Sep 17 00:00:00 2001
From: Jinseong Jeon <jsjeon@google.com>
Date: Thu, 11 Mar 2021 23:46:19 -0800
Subject: [PATCH] FIR CFA: keep UncaughtExceptionPath separated

---
 .../analysis/cfa/PathAwareControlFlowInfo.kt  | 24 +++++++++++++------
 .../tests/initializedAfterRethrow.fir.kt      |  8 +++----
 2 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/PathAwareControlFlowInfo.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/PathAwareControlFlowInfo.kt
index 269fc45dd7f..5cc69eb63eb 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/PathAwareControlFlowInfo.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/PathAwareControlFlowInfo.kt
@@ -7,10 +7,7 @@ package org.jetbrains.kotlin.fir.analysis.cfa
 
 import kotlinx.collections.immutable.PersistentMap
 import kotlinx.collections.immutable.persistentMapOf
-import org.jetbrains.kotlin.fir.resolve.dfa.cfg.CFGNode
-import org.jetbrains.kotlin.fir.resolve.dfa.cfg.EdgeLabel
-import org.jetbrains.kotlin.fir.resolve.dfa.cfg.NormalPath
-import org.jetbrains.kotlin.fir.resolve.dfa.cfg.TryExpressionExitNode
+import org.jetbrains.kotlin.fir.resolve.dfa.cfg.*
 
 abstract class PathAwareControlFlowInfo<P : PathAwareControlFlowInfo<P, S>, S : ControlFlowInfo<S, *, *>>(
     map: PersistentMap<EdgeLabel, S>,
@@ -43,11 +40,24 @@ abstract class PathAwareControlFlowInfo<P : PathAwareControlFlowInfo<P, S>, S :
 
         val hasAbnormalLabels = map.keys.any { !it.isNormal }
         return if (hasAbnormalLabels) {
-            // { |-> ... l1 |-> I1, l2 |-> I2, ... }
+            // { |-> ..., l1 |-> I1, l2 |-> I2, ... }
             //   | l1         // path exit: if the given info has non-null labels, this acts like a filtering
-            // { |-> I1 }     // NB: remove the path info
+            // { |-> I1 }     // NB: remove the path label, except for uncaught exception path
             if (map.keys.contains(label)) {
-                constructor(persistentMapOf(NormalPath to map[label]!!))
+                if (label == UncaughtExceptionPath) {
+                    // Special case: uncaught exception path, which still represents an uncaught exception path
+                    // Target node is most likely fun/init exit, and we should keep info separated.
+                    constructor(persistentMapOf(label to map[label]!!))
+                } else {
+                    // { |-> I }
+                    //   | l1       // e.g., enter to proxy1 with l1
+                    // { l1 -> I }
+                    //   ...
+                    // { |-> ..., l1 -> I', ... }
+                    //   | l1       // e.g., exit proxy1 with l1
+                    // { l1 -> I' }
+                    constructor(persistentMapOf(NormalPath to map[label]!!))
+                }
             } else {
                 /* This means no info for the specific label. */
                 empty()
diff --git a/compiler/testData/diagnostics/tests/initializedAfterRethrow.fir.kt b/compiler/testData/diagnostics/tests/initializedAfterRethrow.fir.kt
index 77660e93157..3b2c5705aca 100644
--- a/compiler/testData/diagnostics/tests/initializedAfterRethrow.fir.kt
+++ b/compiler/testData/diagnostics/tests/initializedAfterRethrow.fir.kt
@@ -13,7 +13,7 @@ object ThrowInTryWithCatch {
 }
 
 object ThrowInTryWithCatchAndFinally {
-    <!MUST_BE_INITIALIZED_OR_BE_ABSTRACT!>private val p: String<!>
+    private val p: String
 
     init {
         try {
@@ -53,7 +53,7 @@ object RethrowInCatch {
 }
 
 object RethrowInCatchWithFinally {
-    <!MUST_BE_INITIALIZED_OR_BE_ABSTRACT!>private val p: String<!>
+    private val p: String
 
     init {
         try {
@@ -134,7 +134,7 @@ object InnerCatch {
 }
 
 object InnerCatchWithFinally {
-    <!MUST_BE_INITIALIZED_OR_BE_ABSTRACT!>private val p: String<!>
+    private val p: String
 
     init {
         try {
@@ -169,7 +169,7 @@ object InnerCatchOuterRethrow {
 }
 
 object InnerCatchOuterRethrowWithFinally {
-    <!MUST_BE_INITIALIZED_OR_BE_ABSTRACT!>private val p: String<!>
+    private val p: String
 
     init {
         try {