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src/hotspot/share/code/dependencies.hpp

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  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_CODE_DEPENDENCIES_HPP
  26 #define SHARE_VM_CODE_DEPENDENCIES_HPP
  27 
  28 #include "ci/ciCallSite.hpp"
  29 #include "ci/ciKlass.hpp"
  30 #include "ci/ciMethodHandle.hpp"
  31 #include "classfile/systemDictionary.hpp"
  32 #include "code/compressedStream.hpp"
  33 #include "code/nmethod.hpp"
  34 #include "memory/resourceArea.hpp"

  35 #include "utilities/growableArray.hpp"
  36 #include "utilities/hashtable.hpp"
  37 
  38 //** Dependencies represent assertions (approximate invariants) within
  39 // the runtime system, e.g. class hierarchy changes.  An example is an
  40 // assertion that a given method is not overridden; another example is
  41 // that a type has only one concrete subtype.  Compiled code which
  42 // relies on such assertions must be discarded if they are overturned
  43 // by changes in the runtime system.  We can think of these assertions
  44 // as approximate invariants, because we expect them to be overturned
  45 // very infrequently.  We are willing to perform expensive recovery
  46 // operations when they are overturned.  The benefit, of course, is
  47 // performing optimistic optimizations (!) on the object code.
  48 //
  49 // Changes in the class hierarchy due to dynamic linking or
  50 // class evolution can violate dependencies.  There is enough
  51 // indexing between classes and nmethods to make dependency
  52 // checking reasonably efficient.
  53 
  54 class ciEnv;




  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_CODE_DEPENDENCIES_HPP
  26 #define SHARE_VM_CODE_DEPENDENCIES_HPP
  27 
  28 #include "ci/ciCallSite.hpp"
  29 #include "ci/ciKlass.hpp"
  30 #include "ci/ciMethodHandle.hpp"
  31 #include "classfile/systemDictionary.hpp"
  32 #include "code/compressedStream.hpp"
  33 #include "code/nmethod.hpp"
  34 #include "memory/resourceArea.hpp"
  35 #include "runtime/safepointVerifiers.hpp"
  36 #include "utilities/growableArray.hpp"
  37 #include "utilities/hashtable.hpp"
  38 
  39 //** Dependencies represent assertions (approximate invariants) within
  40 // the runtime system, e.g. class hierarchy changes.  An example is an
  41 // assertion that a given method is not overridden; another example is
  42 // that a type has only one concrete subtype.  Compiled code which
  43 // relies on such assertions must be discarded if they are overturned
  44 // by changes in the runtime system.  We can think of these assertions
  45 // as approximate invariants, because we expect them to be overturned
  46 // very infrequently.  We are willing to perform expensive recovery
  47 // operations when they are overturned.  The benefit, of course, is
  48 // performing optimistic optimizations (!) on the object code.
  49 //
  50 // Changes in the class hierarchy due to dynamic linking or
  51 // class evolution can violate dependencies.  There is enough
  52 // indexing between classes and nmethods to make dependency
  53 // checking reasonably efficient.
  54 
  55 class ciEnv;


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