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  1. JDK
  2. JDK-8168318

PPC64: Use cmpldi instead of li/cmpld

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    • b146
    • ppc
    • linux

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        On profiling some specific Neo4j workloads, some cases where a sequence of load (li) and compare (cmpld) can be
        replaced by a single cmpldi instructions were identified. On replacing that sequence by a single instruction it's
        possible to reduce the path length so the program is shorter, and therefore is faster.

        Additionally, the 2 instruction sequence requires an additional register that with enough register pressure a
        spill would be needed to accommodate that approach.

        It's related to the discussion started here:
        http://mail.openjdk.java.net/pipermail/hotspot-compiler-dev/2016-October/024664.html

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                gromero Gustavo Romero
                gromero Gustavo Romero
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                  Updated:
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