1. 04 Mar, 2019 1 commit
  2. 29 Nov, 2017 1 commit
    • Benedikt Meurer's avatar
      [turbofan] Optimize String#slice(-1) calls. · 3200cc60
      Benedikt Meurer authored
      In TurboFan we can easily recognize calls to String.prototype.slice
      where the start parameter is -1 and the end parameter is either
      undefined or not present. These calls either return an empty string if
      the input string is empty, or the last character of the input string
      as a single character string. So we can just make use of the existing
      StringCharAt operator.
      
      This reduces the overhead of the String.prototype.slice calls from
      optimized code in the chai test of the web-tooling-benchmark
      significantly. We observe a 2-3% improvement on the test.
      
      Bug: v8:6936, v8:7137
      Change-Id: Iebe02667446880f5760e3e8c80f8b7cc712df663
      Reviewed-on: https://chromium-review.googlesource.com/795726
      Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
      Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#49704}
      3200cc60