test/hotspot/gtest/oops/test_oop.cpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "precompiled.hpp"
#include "oops/oop.inline.hpp"
#include "unittest.hpp"
#include "utilities/globalDefinitions.hpp"

static char memory[32];

oop fake_object() {
  return cast_to_oop(memory);
}

template <typename T>
T* fake_field_addr() {
  return reinterpret_cast<T*>(&memory[16]);
}

TEST_VM(oopDesc, field_offset_oop) {
  // Fake object
  oop obj = fake_object();

  // Fake oop field
  oop* oop_field_addr = fake_field_addr<oop>();

  // Check offset
  size_t oop_offset = obj->field_offset(oop_field_addr);
  ASSERT_EQ(16u, oop_offset);
}

TEST_VM(oopDesc, field_offset_narrowOop) {
  // Fake object
  oop obj = fake_object();

  // Fake narrowOop field
  narrowOop* narrowOop_field_addr = fake_field_addr<narrowOop>();

  size_t narrowOop_offset = obj->field_offset(narrowOop_field_addr);
  ASSERT_EQ(16u, narrowOop_offset);
}

TEST_VM(oopDesc, field_offset_primitive) {
  // Fake object
  oop obj = fake_object();

  // Fake primitive field
  char* char_field_addr = fake_field_addr<char>();

  size_t char_offset = obj->field_offset(char_field_addr);
  ASSERT_EQ(16u, char_offset);
}