• Jaideep Bajwa's avatar
    PPC/s390: [turbofan] Widen the fast-path for JSCreateArray. · 00a8ab2e
    Jaideep Bajwa authored
    Port 1edb46cc
    
    Original Commit Message:
    
        This improves the general Array constructor call performance (w/o
        usable AllocationSite feedback) in TurboFan by ~2x, i.e. for example
        invoking the Array constructor like this
    
          var a = Array.call(undefined, n);
    
        instead of
    
          var a = Array(n);
    
        such that the CallIC doesn't know that it's eventually calling the
        Array constructor.
    
        It also thus changes the single argument Array constructor to always
        return holey arrays. Previously the single argument case for the Array
        constructor was somehow trying to dynamically detect 0 and in that case
        returned a packed array instead of a holey one. That adds quite a lot
        of churn, and doesn't seem to be very useful, especially since this
        might lead to unnecessary feedback pollution later.
    
    R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
    BUG=
    LOG=N
    
    Change-Id: I6a50ae016556ed38a7d7ca5546b575ca25e91b4a
    Reviewed-on: https://chromium-review.googlesource.com/586641Reviewed-by: 's avatarJunliang Yan <jyan@ca.ibm.com>
    Commit-Queue: Jaideep Bajwa <bjaideep@ca.ibm.com>
    Cr-Commit-Position: refs/heads/master@{#46909}
    00a8ab2e
code-stubs-ppc.cc 102 KB