From e1abaa9b512d6c254a0a3534305f817483a8684f Mon Sep 17 00:00:00 2001
From: Jinseong Jeon <jsjeon@google.com>
Date: Tue, 21 Jul 2020 10:48:32 -0700
Subject: [PATCH] FIR: special visibility handling for monitor{Enter|Exit}

---
 .../kotlin/fir/resolve/calls/ResolutionStages.kt     | 12 +++++++++++-
 .../box/intrinsics/monitorEnterMonitorExit.kt        |  1 -
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionStages.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionStages.kt
index 94e35d12994..b495012c3b5 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionStages.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionStages.kt
@@ -438,7 +438,7 @@ internal object CheckVisibility : CheckerStage() {
                         canSeePrivateMemberOf(containingDeclarations, ownerId, session)
                     }
                 } else {
-                    false
+                    declaration is FirSimpleFunction && declaration.isAllowedToBeAccessedFromOutside()
                 }
             }
             Visibilities.PROTECTED -> {
@@ -461,6 +461,16 @@ internal object CheckVisibility : CheckerStage() {
         return true
     }
 
+    // monitorEnter/monitorExit are the only functions which are accessed "illegally" (see kotlin/util/Synchronized.kt).
+    // Since they are intrinsified in the codegen, FIR should treat it as visible.
+    private fun FirSimpleFunction.isAllowedToBeAccessedFromOutside(): Boolean {
+        if (!isFromLibrary) return false
+        val packageName = symbol.callableId.packageName.asString()
+        val name = name.asString()
+        return packageName == "kotlin.jvm.internal.unsafe" &&
+                (name == "monitorEnter" || name == "monitorExit")
+    }
+
     private fun AbstractFirBasedSymbol<*>.getOwnerId(): ClassId? {
         return when (this) {
             is FirClassLikeSymbol<*> -> {
diff --git a/compiler/testData/codegen/box/intrinsics/monitorEnterMonitorExit.kt b/compiler/testData/codegen/box/intrinsics/monitorEnterMonitorExit.kt
index 2481400aafd..c157415377c 100644
--- a/compiler/testData/codegen/box/intrinsics/monitorEnterMonitorExit.kt
+++ b/compiler/testData/codegen/box/intrinsics/monitorEnterMonitorExit.kt
@@ -1,5 +1,4 @@
 // TARGET_BACKEND: JVM
-// IGNORE_BACKEND_FIR: JVM_IR
 // WITH_RUNTIME
 
 import kotlin.jvm.internal.unsafe.*