From 06fb10fecf1ee373a6e13f572523100ee75fa87e Mon Sep 17 00:00:00 2001
From: Quan Anh Mai <anhmdq99@gmail.com>
Date: Mon, 29 Dec 2025 21:43:47 +0700
Subject: [PATCH] Fix escape at store

---
 src/hotspot/share/opto/memnode.cpp            | 43 +++++++------------
 .../escapeAnalysis/TestLoadFolding.java       |  8 ++--
 2 files changed, 19 insertions(+), 32 deletions(-)

diff --git a/src/hotspot/share/opto/memnode.cpp b/src/hotspot/share/opto/memnode.cpp
index 977cf6f3b74..93455038d74 100644
--- a/src/hotspot/share/opto/memnode.cpp
+++ b/src/hotspot/share/opto/memnode.cpp
@@ -1506,34 +1506,21 @@ MemNode::LocalEA::EscapeStatus MemNode::LocalEA::check_escape_status(Node* ctl)
       } else if (out->is_Mem()) {
         // A Store or a LoadStore
         if (n == out->in(MemNode::ValueIn)) {
-          Node* ptr = out->in(MemNode::Address);
-          if (ptr->is_AddP()) {
-            Node* ptr_base = ptr->as_AddP()->base_node();
-            if (!_phase->type(ptr_base)->isa_oopptr()) {
-              // Maybe a store to raw memory
-              res = ESCAPED;
-              break;
-            }
-
-            // If an object o is stored into a field of a holder h and h has not escaped, we can
-            // say that o has not escaped, too
-            LocalEA store_base_ea(_phase, ptr->as_AddP()->base_node());
-            if (!store_base_ea.is_candidate()) {
-              res = ESCAPED;
-              break;
-            }
-
-            // This is similar to store_base_ea.check_escape_status(ctl), the differences are that
-            // it avoids the drawbacks of recursion and does not unnecessarily collect
-            // _not_escaped_controls again
-            for (uint i = 0; i < store_base_ea.aliases().size(); i++) {
-              dependencies.push(store_base_ea.aliases().at(i));
-            }
-          } else {
-            // Do not know into where n is stored, give up
-            res = ESCAPED;
-            break;
-          }
+          // You may wonder if we can reason about the escape status of the destination memory
+          // here so that we can determine that an object has not escaped if the object into which
+          // it is stored has not escaped. Unfortunately, this store breaks _aliases, because there
+          // is now a memory that can alias the object we are analyzed, and a load from such memory
+          // is not visited by this analysis. For example:
+          //   Object o = new Object;
+          //   Holder h = new Holder;
+          //   h.o = o;
+          //   do_something();
+          //   Object p = h.o;
+          //   escape(p);
+          // Then, o escapes at escape(p), but we will not visit that. In order for this to work,
+          // the constructor needs to be more conservative when it collects _aliases.
+          res = ESCAPED;
+          break;
         } else if (n == out->in(MemNode::Address) && (!out->is_Store() || out->as_Store()->is_mismatched_access())) {
           // Mismatched accesses can lie in a different alias class and are protected by memory
           // barriers, so we cannot be aggressive and walk past memory barriers if there is a
diff --git a/test/hotspot/jtreg/compiler/escapeAnalysis/TestLoadFolding.java b/test/hotspot/jtreg/compiler/escapeAnalysis/TestLoadFolding.java
index 4b2076e9756..0cf0ebfb623 100644
--- a/test/hotspot/jtreg/compiler/escapeAnalysis/TestLoadFolding.java
+++ b/test/hotspot/jtreg/compiler/escapeAnalysis/TestLoadFolding.java
@@ -241,7 +241,7 @@ public class TestLoadFolding {
     }
 
     @Test
-    @IR(applyIf = {"DoLocalEscapeAnalysis", "true"}, failOn = IRNode.LOAD_I, counts = {IRNode.ALLOC, "1"})
+    @IR(applyIf = {"DoLocalEscapeAnalysis", "true"}, counts = {IRNode.ALLOC, "1"})
     public int test112() {
         // The object has been stored into memory but the destination does not escape
         PointHolder h = new PointHolder();
@@ -254,7 +254,7 @@ public class TestLoadFolding {
     }
 
     @Test
-    @IR(applyIf = {"DoLocalEscapeAnalysis", "true"}, failOn = IRNode.LOAD_I, counts = {IRNode.ALLOC, "2"})
+    @IR(applyIf = {"DoLocalEscapeAnalysis", "true"}, counts = {IRNode.ALLOC, "2"})
     public int test113() {
         // The object has been stored into memory but the destination has not escaped
         PointHolder h = new PointHolder();
@@ -267,7 +267,7 @@ public class TestLoadFolding {
     }
 
     @Test
-    @IR(applyIf = {"DoLocalEscapeAnalysis", "true"}, failOn = IRNode.LOAD_I, counts = {IRNode.ALLOC, "3"})
+    @IR(applyIf = {"DoLocalEscapeAnalysis", "true"}, counts = {IRNode.ALLOC, "3"})
     public int test114(boolean b) {
         // A Phi has been stored into memory but the destination has not escaped
         PointHolder h = new PointHolder();
@@ -281,7 +281,7 @@ public class TestLoadFolding {
     }
 
     @Test
-    @IR(applyIf = {"DoLocalEscapeAnalysis", "true"}, failOn = IRNode.LOAD_I, counts = {IRNode.ALLOC, "3"})
+    @IR(applyIf = {"DoLocalEscapeAnalysis", "true"}, counts = {IRNode.ALLOC, "3"})
     public int test115(boolean b) {
         // The object has been stored into a Phi but the destination has not escaped
         PointHolder h1 = new PointHolder();