test_objectMonitor.cpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "precompiled.hpp"
#include "runtime/objectMonitor.hpp"
#include "runtime/vm_version.hpp"
#include "unittest.hpp"

TEST_VM(ObjectMonitor, sanity) {
 uint cache_line_size = VM_Version::L1_data_cache_line_size();

 if (cache_line_size != 0) {
   // We were able to determine the L1 data cache line size so
   // do some cache line specific sanity checks
   EXPECT_EQ((size_t) 0, sizeof (PaddedEnd<ObjectMonitor>) % cache_line_size)
        << "PaddedEnd<ObjectMonitor> size is not a "
        << "multiple of a cache line which permits false sharing. "
        << "sizeof(PaddedEnd<ObjectMonitor>) = "
        << sizeof (PaddedEnd<ObjectMonitor>)
        << "; cache_line_size = " << cache_line_size;

   EXPECT_GE((size_t) ObjectMonitor::owner_offset_in_bytes(), cache_line_size)
        << "the _header and _owner fields are closer "
        << "than a cache line which permits false sharing.";
  }
}