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  2. JDK-8368732

RISC-V: Detect support for misaligned vector access via hwprobe

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    • Icon: Enhancement Enhancement
    • Resolution: Unresolved
    • Icon: P4 P4
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    • riscv
    • linux

      According to the latest RISC-V linux hardware probing syscall [1], the performance of misaligned memory accesses has been divided into two cases: `RISCV_HWPROBE_KEY_MISALIGNED_SCALAR_PERF` and `RISCV_HWPROBE_KEY_MISALIGNED_VECTOR_PERF` for scalar and vector respectively.

      This aligns `AlignVector` with `RISCV_HWPROBE_KEY_MISALIGNED_VECTOR_PERF`. That is if the misaligned vector access is fast, we set `AlignVector` to false in the hope that it will save instructions handling address alignment thus improves performance.

            fyang Fei Yang
            fyang Fei Yang
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