jdk8-mips64-public/hotspot: src/cpu/x86/vm/icache

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    25 // Interface for updating the instruction cache.  Whenever the VM modifies

    26 // code, part of the processor instruction cache potentially has to be flushed.

    28 // On the x86, this is a no-op -- the I-cache is guaranteed to be consistent

    29 // after the next jump, and the VM never modifies instructions directly ahead

    30 // of the instruction fetch path.

    32 // [phh] It's not clear that the above comment is correct, because on an MP

    33 // system where the dcaches are not snooped, only the thread doing the invalidate

    34 // will see the update.  Even in the snooped case, a memory fence would be

    35 // necessary if stores weren't ordered.  Fortunately, they are on all known

    36 // x86 implementations.

    38 class ICache : public AbstractICache {

    39  public:

    40 #ifdef AMD64

    41   enum {

    42     stub_size      = 64, // Size of the icache flush stub in bytes

    43     line_size      = 32, // Icache line size in bytes

    44     log2_line_size = 5   // log2(line_size)

    45   };

    47   // Use default implementation

    48 #else

    49   enum {

    50     stub_size      = 16,                 // Size of the icache flush stub in bytes

    51     line_size      = BytesPerWord,      // conservative

    52     log2_line_size = LogBytesPerWord    // log2(line_size)

    53   };

    54 #endif // AMD64

    55 };

src/cpu/x86/vm/icache_x86.hpp@e9ff18c4ace7