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8255466: C2 crashes at ciObject::get_oop() const+0x0
Reviewed-by: vlivanov
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Vladimir Kozlov committed Oct 29, 2020
1 parent 5782a2a commit 56eb5f54f40d2e1c3bdfbf440f2c5e1572639bc9
@@ -3046,9 +3046,11 @@ TypeOopPtr::TypeOopPtr(TYPES t, PTR ptr, ciKlass* k, bool xk, ciObject* o, int o
} else if (klass() == ciEnv::current()->Class_klass() &&
_offset >= InstanceMirrorKlass::offset_of_static_fields()) {
// Static fields
assert(o != NULL, "must be constant");
ciInstanceKlass* k = o->as_instance()->java_lang_Class_klass()->as_instance_klass();
ciField* field = k->get_field_by_offset(_offset, true);
ciField* field = NULL;
if (const_oop() != NULL) {
ciInstanceKlass* k = const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
field = k->get_field_by_offset(_offset, true);
}
if (field != NULL) {
BasicType basic_elem_type = field->layout_type();
_is_ptr_to_narrowoop = UseCompressedOops && is_reference_type(basic_elem_type);
@@ -100,7 +100,10 @@ static bool is_vector_shuffle(ciKlass* klass) {
}

static bool is_klass_initialized(const TypeInstPtr* vec_klass) {
assert(vec_klass->const_oop()->as_instance()->java_lang_Class_klass(), "klass instance expected");
if (vec_klass->const_oop() == NULL) {
return false; // uninitialized or some kind of unsafe access
}
assert(vec_klass->const_oop()->as_instance()->java_lang_Class_klass() != NULL, "klass instance expected");
ciInstanceKlass* klass = vec_klass->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
return klass->is_initialized();
}
@@ -0,0 +1,62 @@
/*
* Copyright (c) 2020, 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
* @bug 8255466
* @summary unsafe access to static field causes crash
* @modules java.base/jdk.internal.misc
*
* @run main/othervm -Xcomp -XX:CompileCommand=compileonly,TestUnsafeStaticFieldAccess::* TestUnsafeStaticFieldAccess
*
*/

import jdk.internal.misc.Unsafe;
import java.lang.reflect.Field;

public class TestUnsafeStaticFieldAccess {
private static final Unsafe UNSAFE = Unsafe.getUnsafe();
private static final long offset;
private static volatile Class<?> clazz;

private static int field;

static {
long o = 0;
for (Field f : TestUnsafeStaticFieldAccess.class.getDeclaredFields()) {
if (f.getName().equals("field")) {
o = UNSAFE.staticFieldOffset(f);
break;
}
}
offset = o;
clazz = TestUnsafeStaticFieldAccess.class;
}


public static void main(String[] args) {
for (int i = 0; i < 12000; i++) {
UNSAFE.getInt(clazz, offset);
}
}
}

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