Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-8270848

Redundant unsafe opmask register allocation in some instruction patterns.

    XMLWordPrintable

    Details

    • Subcomponent:
    • Resolved In Build:
      b09
    • CPU:
      x86

      Description

      - Some string compare/array equality patters in x86_[32/64].ad files accept the temporary opmark register operands, instructions using these registers are guarded by target feature checks.
      - Even if control path leading to these instructions is not chosen, RA will still allocate physical registers to these temporary operands.
      - Pulling out the feature checks upto the instruction level can save redundant allocations which may effect spilling decisions.
      - Existing platform dependent routine Matcher::has_predicated_vector() check the existence of AVX512VL feature which is not required.

        Attachments

          Issue Links

            Activity

              People

              Assignee:
              jbhateja Jatin Bhateja
              Reporter:
              jbhateja Jatin Bhateja
              Votes:
              0 Vote for this issue
              Watchers:
              4 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved: