From 8032d640c0d34fe507392a1d4faa4ff2005c771d Mon Sep 17 00:00:00 2001
From: Roland Westrelin <roland@openjdk.org>
Date: Wed, 15 May 2024 12:01:20 +0000
Subject: [PATCH] 8332245: C2: missing record_for_ign() call in
 GraphKit::must_be_not_null()

Reviewed-by: thartmann, chagedorn
---
 src/hotspot/share/opto/graphKit.cpp           |  3 +
 .../irTests/TestBackToBackMustBeNotNull.java  | 74 +++++++++++++++++++
 2 files changed, 77 insertions(+)
 create mode 100644 test/hotspot/jtreg/compiler/c2/irTests/TestBackToBackMustBeNotNull.java

diff --git a/src/hotspot/share/opto/graphKit.cpp b/src/hotspot/share/opto/graphKit.cpp
index 794403611e5..bcf4ee40424 100644
--- a/src/hotspot/share/opto/graphKit.cpp
+++ b/src/hotspot/share/opto/graphKit.cpp
@@ -1468,6 +1468,9 @@ Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
   Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1)));
   IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
   _gvn.set_type(iff, iff->Value(&_gvn));
+  if (!tst->is_Con()) {
+    record_for_igvn(iff);
+  }
   Node *if_f = _gvn.transform(new IfFalseNode(iff));
   Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
   Node* halt = _gvn.transform(new HaltNode(if_f, frame, "unexpected null in intrinsic"));
diff --git a/test/hotspot/jtreg/compiler/c2/irTests/TestBackToBackMustBeNotNull.java b/test/hotspot/jtreg/compiler/c2/irTests/TestBackToBackMustBeNotNull.java
new file mode 100644
index 00000000000..9487df23d1c
--- /dev/null
+++ b/test/hotspot/jtreg/compiler/c2/irTests/TestBackToBackMustBeNotNull.java
@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) 2024, Red Hat, Inc. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8332245
+ * @summary C2: missing record_for_ign() call in GraphKit::must_be_not_null()
+ *
+ * @modules java.base/jdk.internal.misc
+ * @library /test/lib /
+ * @run driver compiler.c2.irTests.TestBackToBackMustBeNotNull
+ */
+
+package compiler.c2.irTests;
+import jdk.internal.misc.Unsafe;
+import java.lang.reflect.Field;
+import compiler.lib.ir_framework.*;
+
+
+public class TestBackToBackMustBeNotNull {
+    static final jdk.internal.misc.Unsafe UNSAFE = Unsafe.getUnsafe();
+    static final long F_OFFSET;
+    private static A fieldA = new A();
+
+    static {
+        try {
+            Field fField = A.class.getDeclaredField("f");
+            F_OFFSET = UNSAFE.objectFieldOffset(fField);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    static public void main(String[] args) {
+        TestFramework.runWithFlags("--add-modules", "java.base", "--add-exports", "java.base/jdk.internal.misc=ALL-UNNAMED");
+    }
+
+    @Test
+    @IR(phase = { CompilePhase.ITER_GVN1 }, counts = { IRNode.IF, "1" })
+    private static void test1() {
+        final Object o1 = UNSAFE.getReference(fieldA, F_OFFSET);
+        final Object o2 = UNSAFE.getReference(fieldA, F_OFFSET);
+        notInlined(o1, o2);
+    }
+
+    @DontInline
+    private static void notInlined(Object o1, Object o2) {
+
+    }
+
+    static class A {
+        Object f;
+    }
+}