// Copyright 2015 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // Flags: --allow-natives-syntax function boom(a1, a2) { // Do something with a2 that needs a map check (for DOUBLE_ELEMENTS). var s = a2[0]; // Emit a load that transitions a1 to PACKED_ELEMENTS. var t = a1[0]; // Emit a store to a2 that assumes DOUBLE_ELEMENTS. // The map check is considered redundant and will be eliminated. a2[0] = 0.3; } // Prepare type feedback for the "t = a1[0]" load: fast elements. ; %PrepareFunctionForOptimization(boom); var fast_elem = new Array(1); fast_elem[0] = 'tagged'; boom(fast_elem, [1]); // Prepare type feedback for the "a2[0] = 0.3" store: double elements. var double_elem = new Array(1); double_elem[0] = 0.1; boom(double_elem, double_elem); // Reset |double_elem| and go have a party. double_elem = new Array(10); double_elem[0] = 0.1; %OptimizeFunctionOnNextCall(boom); boom(double_elem, double_elem); assertEquals(0.3, double_elem[0]); assertEquals(undefined, double_elem[1]);