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    Revert of [turbofan] Implement rounding of floats on x64 and ia32 without... · 900b2933
    ahaas authored
    Revert of [turbofan] Implement rounding of floats on x64 and ia32 without sse4.1. (patchset #2 id:20001 of https://codereview.chromium.org/1584663007/ )
    
    Reason for revert:
    Code is incorrect for -0.
    
    Original issue's description:
    > [turbofan] Implement rounding of floats on x64 and ia32 without sse4.1.
    >
    > The implementation sets the rounding mode flag and then uses the
    > cvtsd2si and cvtsi2sd instructions (convert between float and int) to do
    > the rounding. Input values outside int range either don't have to be
    > rounded anyways, or are rounded by calculating input + 2^52 - 2^52 for
    > positive inputs, or input -2^52 + 2^52 for negative inputs. The original
    > rounding mode is restored afterwards.
    >
    > R=titzer@chromium.org
    >
    > B=575379
    >
    > Committed: https://crrev.com/fa5d09e547abe79a8c82f780deb980c53ad78beb
    > Cr-Commit-Position: refs/heads/master@{#33367}
    
    TBR=titzer@chromium.org
    # Skipping CQ checks because original CL landed less than 1 days ago.
    NOPRESUBMIT=true
    NOTREECHECKS=true
    NOTRY=true
    
    Review URL: https://codereview.chromium.org/1593313010
    
    Cr-Commit-Position: refs/heads/master@{#33369}
    900b2933
disasm-ia32.cc 69.3 KB