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bmeurer authored
Move JSOrdinaryHasInstance lowering to JSNativeContextSpecialization, which was previously mostly done in JSTypedLowering (for no reason). Add new logic to the lowering to constant-fold OrdinaryHasInstance checks when the map of the left-hand side and the "prototype" of the right-hand side is known. This address the performance issue with the (base) class constructors generated by Babel, i.e.: function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } } var C = function C() { _classCallCheck(this, C); }; for class C {} Also ensure that a known constructor being used inside an instanceof get's a proper initial map on-demand. BUG=v8:6275 R=mstarzinger@chromium.org Review-Url: https://codereview.chromium.org/2827013002 Cr-Commit-Position: refs/heads/master@{#44727}
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