Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-8258932

AArch64: Enhance floating-point Min/MaxReductionV with fminp/fmaxp

    XMLWordPrintable

    Details

    • Type: Enhancement
    • Status: Resolved
    • Priority: P4
    • Resolution: Fixed
    • Affects Version/s: 17
    • Fix Version/s: 17
    • Component/s: hotspot
    • Labels:
    • Subcomponent:
    • Resolved In Build:
      b05
    • CPU:
      aarch64
    • OS:
      linux

      Description

      In aarch64, current implemention of floating-point Min/MaxReductionV with 2 elements can be optimized via fminp/fmaxp instructions.

      Take `Set dst (MaxReductionV dsrc vsrc)` as an example:
      ---------- now ---------
      fmaxs $dst, $dsrc, $vsrc
      ins $tmp, S, $vsrc, 0, 1
      fmaxs $dst, $dst, $tmp
      -------- optimized -----
      fmaxp $dst, $vsrc, D
      fmaxs $dst, $dst, $dsrc

      Witnessed about 25% improvements with an intitial implementation on an A72-based aarch64 server.

        Attachments

          Issue Links

            Activity

              People

              Assignee:
              dongbo Dong Bo
              Reporter:
              dongbo Dong Bo
              Votes:
              0 Vote for this issue
              Watchers:
              3 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved: