hotspot/src/share/vm/runtime/prefetch.hpp
author stefank
Tue, 23 Nov 2010 13:22:55 -0800
changeset 7397 5b173b4ca846
parent 5547 f4b087cbb361
permissions -rw-r--r--
6989984: Use standard include model for Hospot Summary: Replaced MakeDeps and the includeDB files with more standardized solutions. Reviewed-by: coleenp, kvn, kamg

/*
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 * accompanied this code).
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#ifndef SHARE_VM_RUNTIME_PREFETCH_HPP
#define SHARE_VM_RUNTIME_PREFETCH_HPP

#include "memory/allocation.hpp"

// If calls to prefetch methods are in a loop, the loop should be cloned
// such that if Prefetch{Scan,Copy}Interval and/or PrefetchFieldInterval
// say not to do prefetching, these methods aren't called.  At the very
// least, they take up a memory issue slot.  They should be implemented
// as inline assembly code: doing an actual call isn't worth the cost.

class Prefetch : AllStatic {
 public:
  enum style {
    do_none,  // Do no prefetching
    do_read,  // Do read prefetching
    do_write  // Do write prefetching
  };

  // Prefetch anticipating read; must not fault, semantically a no-op
  static void read(void* loc, intx interval);

  // Prefetch anticipating write; must not fault, semantically a no-op
  static void write(void* loc, intx interval);
};

#endif // SHARE_VM_RUNTIME_PREFETCH_HPP