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#include "config.h" 27#include "FloatingPointEnvironment.h" 28 29#include <wtf/MainThread.h> 30#include <wtf/NeverDestroyed.h> 31 32#if PLATFORM(IOS) 33 34namespace WebCore { 35 36FloatingPointEnvironment& FloatingPointEnvironment::shared() 37{ 38 static NeverDestroyed<FloatingPointEnvironment> floatingPointEnvironment; 39 return floatingPointEnvironment; 40} 41 42FloatingPointEnvironment::FloatingPointEnvironment() 43 : m_isInitialized(false) 44{ 45} 46 47void FloatingPointEnvironment::enableDenormalSupport() 48{ 49 RELEASE_ASSERT(isUIThread()); 50#if defined _ARM_ARCH_7 51 fenv_t env; 52 fegetenv(&env); 53 env.__fpscr &= ~0x01000000U; 54 fesetenv(&env); 55#endif 56 // Supporting denormal mode is already the default on x86, x86_64, and ARM64. 57} 58 59void FloatingPointEnvironment::saveMainThreadEnvironment() 60{ 61 RELEASE_ASSERT(!m_isInitialized); 62 RELEASE_ASSERT(isUIThread()); 63 fegetenv(&m_mainThreadEnvironment); 64 m_isInitialized = true; 65} 66 67void FloatingPointEnvironment::propagateMainThreadEnvironment() 68{ 69 RELEASE_ASSERT(m_isInitialized); 70 RELEASE_ASSERT(!isUIThread()); 71 fesetenv(&m_mainThreadEnvironment); 72} 73 74} // namespace WebCore 75 76#endif // PLATFORM(IOS) 77