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  1. JDK
  2. JDK-8307555

Reduce memory reads in x86 MD5 intrinsic

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    • b23
    • x86

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        The following pattern in MD5 intrinsic is inefficient. The updated value is written to the memory and immediately read back from the memory.

        loop0:
          movl(rax, Address(rdi, 0)); // 4) read the value at the address stored in rdi (The value was just written to the memory.)
          // loop body
          addl(Address(rdi, 0), rax); // 1) read the value at the address stored in rdi, 2) add the value of rax, 3) write back to the address stored in rdi
          // jump to loop0

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                yftsai Yi-Fan Tsai
                yftsai Yi-Fan Tsai
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