From 01a9a4021848aabc4bb68600a89a380a76a33ff1 Mon Sep 17 00:00:00 2001
From: Aleksey Shipilev <shade@openjdk.org>
Date: Mon, 6 Jul 2026 15:44:00 +0000
Subject: [PATCH] 8387721: C2: Print Node barrier data

Reviewed-by: amitkumar, chagedorn
---
 src/hotspot/share/opto/memnode.cpp | 30 ++++++++++++++++++++++++++----
 src/hotspot/share/opto/memnode.hpp |  4 ++++
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/src/hotspot/share/opto/memnode.cpp b/src/hotspot/share/opto/memnode.cpp
index 4f68ff281a0..00ccb3e3dbc 100644
--- a/src/hotspot/share/opto/memnode.cpp
+++ b/src/hotspot/share/opto/memnode.cpp
@@ -86,12 +86,13 @@ bool MemNode::check_if_adr_maybe_raw(Node* adr) {
 
 #ifndef PRODUCT
 void MemNode::dump_spec(outputStream *st) const {
-  if (in(Address) == nullptr)  return; // node is dead
+  if (in(Address) == nullptr) {
+    // node is dead
+    return;
+  }
 #ifndef ASSERT
   // fake the missing field
-  const TypePtr* _adr_type = nullptr;
-  if (in(Address) != nullptr)
-    _adr_type = in(Address)->bottom_type()->isa_ptr();
+  const TypePtr* _adr_type = in(Address)->bottom_type()->isa_ptr();
 #endif
   dump_adr_type(_adr_type, st);
 
@@ -108,6 +109,7 @@ void MemNode::dump_spec(outputStream *st) const {
   if (_unsafe_access) {
     st->print(" unsafe");
   }
+  st->print(" barrier(0x%x)", _barrier_data);
 }
 
 void MemNode::dump_adr_type(const TypePtr* adr_type, outputStream* st) {
@@ -4145,6 +4147,26 @@ MemBarNode* LoadStoreNode::trailing_membar() const {
 
 uint LoadStoreNode::size_of() const { return sizeof(*this); }
 
+#ifndef PRODUCT
+void LoadStoreNode::dump_spec(outputStream* st) const {
+  if (in(MemNode::Address) == nullptr) {
+    // node is dead
+    return;
+  }
+#ifndef ASSERT
+  // fake the missing field
+  const TypePtr* _adr_type = in(MemNode::Address)->bottom_type()->isa_ptr();
+#endif
+  MemNode::dump_adr_type(_adr_type, st);
+
+  Compile* C = Compile::current();
+  if (C->alias_type(_adr_type)->is_volatile()) {
+    st->print(" Volatile!");
+  }
+  st->print(" barrier(0x%x)", _barrier_data);
+}
+#endif
+
 //=============================================================================
 //----------------------------------LoadStoreConditionalNode--------------------
 LoadStoreConditionalNode::LoadStoreConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex ) : LoadStoreNode(c, mem, adr, val, nullptr, TypeInt::BOOL, 5) {
diff --git a/src/hotspot/share/opto/memnode.hpp b/src/hotspot/share/opto/memnode.hpp
index f3f65608972..77252520324 100644
--- a/src/hotspot/share/opto/memnode.hpp
+++ b/src/hotspot/share/opto/memnode.hpp
@@ -880,6 +880,10 @@ public:
   uint8_t barrier_data() { return _barrier_data; }
   void set_barrier_data(uint8_t barrier_data) { _barrier_data = barrier_data; }
 
+#ifndef PRODUCT
+  virtual void dump_spec(outputStream *st) const;
+#endif
+
 private:
   virtual bool depends_only_on_test_impl() const { return false; }
 };