1// Copyright 2013 the V8 project authors. All rights reserved. 2// Redistribution and use in source and binary forms, with or without 3// modification, are permitted provided that the following conditions are 4// met: 5// 6// * Redistributions of source code must retain the above copyright 7// notice, this list of conditions and the following disclaimer. 8// * Redistributions in binary form must reproduce the above 9// copyright notice, this list of conditions and the following 10// disclaimer in the documentation and/or other materials provided 11// with the distribution. 12// * Neither the name of Google Inc. nor the names of its 13// contributors may be used to endorse or promote products derived 14// from this software without specific prior written permission. 15// 16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28// Flags: --allow-natives-syntax 29 30// This is a boiled-down example happening in the Epic Citadel demo: 31// After deopting, the multiplication for unary minus stayed in Smi 32// mode instead of going to double mode, leading to deopt loops. 33 34function unaryMinusTest(x) { 35 var g = (1 << x) | 0; 36 // Optimized code will contain a LMulI with -1 as right operand. 37 return (g & -g) - 1 | 0; 38} 39 40unaryMinusTest(3); 41unaryMinusTest(3); 42%OptimizeFunctionOnNextCall(unaryMinusTest); 43unaryMinusTest(3); 44assertOptimized(unaryMinusTest); 45 46// Deopt on kMinInt 47unaryMinusTest(31); 48// The following is normally true, but not with --stress-opt. :-/ 49// assertUnoptimized(unaryMinusTest); 50 51// We should have learned something from the deopt. 52unaryMinusTest(31); 53%OptimizeFunctionOnNextCall(unaryMinusTest); 54unaryMinusTest(31); 55assertOptimized(unaryMinusTest); 56