1/* 2 * Copyright (C) 2014 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef FTLWeight_h 27#define FTLWeight_h 28 29#if ENABLE(FTL_JIT) 30 31#include <wtf/MathExtras.h> 32#include <wtf/StdLibExtras.h> 33 34namespace JSC { namespace FTL { 35 36class Weight { 37public: 38 Weight() 39 : m_value(std::numeric_limits<float>::quiet_NaN()) 40 { 41 } 42 43 explicit Weight(float value) 44 : m_value(value) 45 { 46 } 47 48 bool isSet() const { return m_value == m_value; } 49 bool operator!() const { return !isSet(); } 50 51 float value() const { return m_value; } 52 53 unsigned scaleToTotal(double total) const 54 { 55 // LLVM accepts 32-bit unsigned branch weights but in dumps it might display them 56 // as signed values. We don't need all 32 bits, so we just use the 31 bits. 57 double result = static_cast<double>(m_value) * INT_MAX / total; 58 if (result < 0) 59 return 0; 60 if (result > INT_MAX) 61 return INT_MAX; 62 return static_cast<unsigned>(result); 63 } 64 65private: 66 float m_value; 67}; 68 69} } // namespace JSC::FTL 70 71#endif // ENABLE(FTL_JIT) 72 73#endif // FTLWeight_h 74 75