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  1. JDK
  2. JDK-8168318

PPC64: Use cmpldi instead of li/cmpld

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    • b146
    • ppc
    • linux

    Backports

      Description

        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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            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8189239 PPC64: Use cmpldi instead of li/cmpld

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8189881 PPC64: Use cmpldi instead of li/cmpld

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8190609 PPC64: Use cmpldi instead of li/cmpld

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8198062 PPC64: Use cmpldi instead of li/cmpld

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

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                gromero Gustavo Romero
                gromero Gustavo Romero
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                  Created:
                  Updated:
                  Resolved: