56 lines
2.4 KiB
JavaScript
56 lines
2.4 KiB
JavaScript
|
// Copyright 2013 the V8 project authors. All rights reserved.
|
||
|
|
// Redistribution and use in source and binary forms, with or without
|
||
|
|
// modification, are permitted provided that the following conditions are
|
||
|
|
// met:
|
||
|
|
//
|
||
|
|
// * Redistributions of source code must retain the above copyright
|
||
|
|
// notice, this list of conditions and the following disclaimer.
|
||
|
|
// * Redistributions in binary form must reproduce the above
|
||
|
|
// copyright notice, this list of conditions and the following
|
||
|
|
// disclaimer in the documentation and/or other materials provided
|
||
|
|
// with the distribution.
|
||
|
|
// * Neither the name of Google Inc. nor the names of its
|
||
|
|
// contributors may be used to endorse or promote products derived
|
||
|
|
// from this software without specific prior written permission.
|
||
|
|
//
|
||
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||
|
|
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||
|
|
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
||
|
|
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
||
|
|
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||
|
|
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||
|
|
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
||
|
|
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
||
|
|
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||
|
|
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||
|
|
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||
|
|
|
||
|
|
// Flags: --allow-natives-syntax
|
||
|
|
|
||
|
|
// This is a boiled-down example happening in the Epic Citadel demo:
|
||
|
|
// After deopting, the multiplication for unary minus stayed in Smi
|
||
|
|
// mode instead of going to double mode, leading to deopt loops.
|
||
|
|
|
||
|
|
function unaryMinusTest(x) {
|
||
|
|
var g = (1 << x) | 0;
|
||
|
|
// Optimized code will contain a LMulI with -1 as right operand.
|
||
|
|
return (g & -g) - 1 | 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
unaryMinusTest(3);
|
||
|
|
unaryMinusTest(3);
|
||
|
|
%OptimizeFunctionOnNextCall(unaryMinusTest);
|
||
|
|
unaryMinusTest(3);
|
||
|
|
assertOptimized(unaryMinusTest);
|
||
|
|
|
||
|
|
// Deopt on kMinInt
|
||
|
|
unaryMinusTest(31);
|
||
|
|
// The following is normally true, but not with --stress-opt. :-/
|
||
|
|
// assertUnoptimized(unaryMinusTest);
|
||
|
|
|
||
|
|
// We should have learned something from the deopt.
|
||
|
|
unaryMinusTest(31);
|
||
|
|
%OptimizeFunctionOnNextCall(unaryMinusTest);
|
||
|
|
unaryMinusTest(31);
|
||
|
|
assertOptimized(unaryMinusTest);
|