1/* 2 * Copyright (C) 2012, 2013, 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 JSStackInlines_h 27#define JSStackInlines_h 28 29#include "CallFrame.h" 30#include "CodeBlock.h" 31#include "JSStack.h" 32#include "VM.h" 33 34namespace JSC { 35 36inline bool JSStack::ensureCapacityFor(Register* newTopOfStack) 37{ 38#if !ENABLE(JIT) 39 return grow(newTopOfStack); 40#else 41 ASSERT(wtfThreadData().stack().isGrowingDownward()); 42 return newTopOfStack >= m_vm.stackLimit(); 43#endif 44} 45 46#if !ENABLE(JIT) 47 48inline Register* JSStack::topOfFrameFor(CallFrame* frame) 49{ 50 if (UNLIKELY(!frame)) 51 return baseOfStack(); 52 return frame->topOfFrame() - 1; 53} 54 55inline Register* JSStack::topOfStack() 56{ 57 return topOfFrameFor(m_topCallFrame); 58} 59 60inline void JSStack::shrink(Register* newTopOfStack) 61{ 62 Register* newEnd = newTopOfStack - 1; 63 if (newEnd >= m_end) 64 return; 65 setStackLimit(newTopOfStack); 66 // Note: Clang complains of an unresolved linkage to maxExcessCapacity if 67 // invoke std::max() with it as an argument. To work around this, we first 68 // assign the constant to a local variable, and use the local instead. 69 ptrdiff_t maxExcessCapacity = JSStack::maxExcessCapacity; 70 ptrdiff_t maxExcessInRegisters = std::max(maxExcessCapacity, m_reservedZoneSizeInRegisters); 71 if (m_end == baseOfStack() && (highAddress() - m_commitTop) >= maxExcessInRegisters) 72 releaseExcessCapacity(); 73} 74 75inline bool JSStack::grow(Register* newTopOfStack) 76{ 77 Register* newEnd = newTopOfStack - 1; 78 if (newEnd >= m_end) 79 return true; 80 return growSlowCase(newTopOfStack); 81} 82 83inline void JSStack::setStackLimit(Register* newTopOfStack) 84{ 85 Register* newEnd = newTopOfStack - 1; 86 m_end = newEnd; 87 m_vm.setJSStackLimit(newTopOfStack); 88} 89 90#endif // !ENABLE(JIT) 91 92} // namespace JSC 93 94#endif // JSStackInlines_h 95