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8357782: JVM JIT Causes Static Initialization Order Issue #25798

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10 changes: 8 additions & 2 deletions src/hotspot/share/c1/c1_ValueMap.hpp
Original file line number Diff line number Diff line change
@@ -1,5 +1,5 @@
/*
* Copyright (c) 1999, 2023, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 1999, 2025, Oracle and/or its affiliates. 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
Expand Down Expand Up @@ -187,7 +187,13 @@ class ValueNumberingVisitor: public InstructionVisitor {
void do_Convert (Convert* x) { /* nothing to do */ }
void do_NullCheck (NullCheck* x) { /* nothing to do */ }
void do_TypeCast (TypeCast* x) { /* nothing to do */ }
void do_NewInstance (NewInstance* x) { /* nothing to do */ }
void do_NewInstance (NewInstance* x) {
ciInstanceKlass* c = x->klass();
if (c != nullptr && !c->is_initialized() &&
(!c->is_loaded() || c->has_class_initializer())) {
kill_memory();
}
}
void do_NewTypeArray (NewTypeArray* x) { /* nothing to do */ }
void do_NewObjectArray (NewObjectArray* x) { /* nothing to do */ }
void do_NewMultiArray (NewMultiArray* x) { /* nothing to do */ }
Expand Down
5 changes: 5 additions & 0 deletions src/hotspot/share/ci/ciInstanceKlass.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -549,6 +549,11 @@ bool ciInstanceKlass::compute_has_trusted_loader() {
return java_lang_ClassLoader::is_trusted_loader(loader_oop);
}

bool ciInstanceKlass::has_class_initializer() {
VM_ENTRY_MARK;
return get_instanceKlass()->class_initializer() != nullptr;
}

// ------------------------------------------------------------------
// ciInstanceKlass::find_method
//
Expand Down
2 changes: 2 additions & 0 deletions src/hotspot/share/ci/ciInstanceKlass.hpp
Original file line number Diff line number Diff line change
Expand Up @@ -231,6 +231,8 @@ class ciInstanceKlass : public ciKlass {
ciInstanceKlass* unique_concrete_subklass();
bool has_finalizable_subclass();

bool has_class_initializer();

bool contains_field_offset(int offset);

// Get the instance of java.lang.Class corresponding to
Expand Down
Original file line number Diff line number Diff line change
@@ -0,0 +1,69 @@
/*
* Copyright (c) 2025, Oracle and/or its affiliates. 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
* @summary Test that C1 respects that static initializers can have memory side effects.
* @bug 8357782
* @requires vm.compiler1.enabled
* @comment Since static initializers only execute in the first execution of the class initializer, we need -Xcomp.
* @run main/othervm -Xcomp -XX:TieredStopAtLevel=1 -XX:CompileCommand=compileonly,compiler/c1/A$B.test compiler.c1.TestStaticInitializerSideEffect
*/

package compiler.c1;

public class TestStaticInitializerSideEffect {
public static void main(String[] args) {
A.B.test();
}
}

class A {
static class B {
static String field;

static void test() {
// This unused variable triggers local value numbering to remove
// the field load in the constructor below if it is not killed
// before.
String tmp = field;
// The class initializer of C should kill the LVN effect of tmp due
// to the memory side effects of the static initializer.
new C(field);
}
}

static class C {
// When executing the class initializer, this has a side effect.
static {
B.field = "Hello";
}

C(String val) {
// If C1 does not respect that side effect, we crash here.
if (val == null) {
throw new RuntimeException("Should not reach here");
}
}
}
}