• Georg Neis's avatar
    Optimize JSCallWithArrayLike with diamond speculation when probable arguments... · 90a24303
    Georg Neis authored
    Optimize JSCallWithArrayLike with diamond speculation when probable arguments list is empty literal array
    
    The JSCallWithArraylike can be replaced with a JSCall if its probable arguments list is empty literal array. This replacement will introduce a deoptimization check to make sure the length of arguments list is 0 at runtime.
    
    This CL change this optimization to a diamond speculation which may help avoid deoptimization once and keep the fast path. This change may benefit a following usecase,
    
    function calcMax(testArray) {
         Array.max = function(array) {
             return Math.max.apply(Math, array);
         };
    
         var result = [];
         for (var i = 0; i < testArray.length - 3; i++) {
             var positiveNumbers = [];
             for (var j = 0; j < 3; j++) {
                 if (testArray[i + j] > 0) {
                     positiveNumbers.push(testArray[i + j]);
                 }
             }
             result.push(Array.max(positiveNumbers));
         }
         return result;
     }
    
     testArray = [-1, 2, 3, -4, -5, -6, -7, -8, -9, 10];
    
     for (var i = 0; i < 1000000; i++) {
         calcMax(testArray);
     }
    
    Bug: v8:9974
    Change-Id: I595627e2fd937527350c8f8652d701c791b41dd3
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2967757
    Commit-Queue: Georg Neis <neis@chromium.org>
    Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#75636}
    90a24303
Name
Last commit
Last update
.github Loading commit data...
bazel Loading commit data...
build_overrides Loading commit data...
custom_deps Loading commit data...
docs Loading commit data...
gni Loading commit data...
include Loading commit data...
infra Loading commit data...
samples Loading commit data...
src Loading commit data...
test Loading commit data...
testing Loading commit data...
third_party Loading commit data...
tools Loading commit data...
.bazelrc Loading commit data...
.clang-format Loading commit data...
.clang-tidy Loading commit data...
.editorconfig Loading commit data...
.flake8 Loading commit data...
.git-blame-ignore-revs Loading commit data...
.gitattributes Loading commit data...
.gitignore Loading commit data...
.gn Loading commit data...
.mailmap Loading commit data...
.vpython Loading commit data...
.ycm_extra_conf.py Loading commit data...
AUTHORS Loading commit data...
BUILD.bazel Loading commit data...
BUILD.gn Loading commit data...
CODE_OF_CONDUCT.md Loading commit data...
COMMON_OWNERS Loading commit data...
DEPS Loading commit data...
DIR_METADATA Loading commit data...
ENG_REVIEW_OWNERS Loading commit data...
INFRA_OWNERS Loading commit data...
INTL_OWNERS Loading commit data...
LICENSE Loading commit data...
LICENSE.fdlibm Loading commit data...
LICENSE.strongtalk Loading commit data...
LICENSE.v8 Loading commit data...
MIPS_OWNERS Loading commit data...
OWNERS Loading commit data...
PPC_OWNERS Loading commit data...
PRESUBMIT.py Loading commit data...
README.md Loading commit data...
RISCV_OWNERS Loading commit data...
S390_OWNERS Loading commit data...
WATCHLISTS Loading commit data...
WORKSPACE Loading commit data...
codereview.settings Loading commit data...