• Fanchen Kong's avatar
    Collect receiver to feedback for prototype.apply · 519c82ce
    Fanchen Kong authored
    When a function is invoked by prototype.apply, it may undergo following transformation in the JSCallReducer:
    	receiver.apply(this, args) ->
    	this.receiver(...args) Since the new target (also the receiver of apply()) is not collected to the feedback slot, further speculative optimization on the new target is not available if the new target
    is not a heapconstant.
    
    With this CL, the receiver will be collected to the feedback instead of the target if the target is a prototype.apply. It may improve the performance of the following usecase by ~80%.
    
    function reduceArray(func, arr, r) {
        for (var i = 0, len = arr.length; i < len; i++) {
                r = func.apply(null, r, arr[i]);
        }
        return r;
    }
    
    var a = 0; for (var i = 0; i < 10000000; i++) {
        a += reduceArray(Math.imul, [5,6,2,3,7,6,8,3,7,9,2,5,], 1);
    }
    console.log(a);
    
    This CL also improves the runTime score of JetStream2/richards-wasm by ~45% in default, ~60% with --turbo-inline-js-wasm-calls.
    
    Change-Id: I542eb8d3fcb592f4e0993af93ba1af70e89c3982
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639813
    Commit-Queue: Fanchen Kong <fanchen.kong@intel.com>
    Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
    Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#74413}
    519c82ce
js-call-reducer.cc 312 KB