/* * Copyright (C) 2013, 2015 Apple Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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. */ #pragma once #include "BytecodeLivenessAnalysis.h" #include "Operands.h" #include <wtf/FastBitVector.h> namespace JSC { class BytecodeLivenessAnalysis; class CodeBlock; // Note: Full bytecode liveness does not track any information about the liveness of temps. // If you want tmp liveness for a checkpoint ask tmpLivenessForCheckpoint. class FullBytecodeLiveness { WTF_MAKE_FAST_ALLOCATED; public: const FastBitVector& getLiveness(BytecodeIndex bytecodeIndex, LivenessCalculationPoint point) const { // We don't have to worry about overflowing into the next bytecodeoffset in our vectors because we // static assert that bytecode length is greater than the number of checkpoints in BytecodeStructs.h switch (point) { case LivenessCalculationPoint::BeforeUse: return m_usesBefore[toIndex(bytecodeIndex)]; case LivenessCalculationPoint::AfterUse: return m_usesAfter[toIndex(bytecodeIndex)]; } RELEASE_ASSERT_NOT_REACHED(); } bool virtualRegisterIsLive(VirtualRegister reg, BytecodeIndex bytecodeIndex, LivenessCalculationPoint point) const { return virtualRegisterIsAlwaysLive(reg) || virtualRegisterThatIsNotAlwaysLiveIsLive(getLiveness(bytecodeIndex, point), reg); } private: friend class BytecodeLivenessAnalysis; static size_t toIndex(BytecodeIndex bytecodeIndex) { return bytecodeIndex.offset() + bytecodeIndex.checkpoint(); } // FIXME: Use FastBitVector's view mechanism to make them compact. // https://bugs.webkit.org/show_bug.cgi?id=204427 Vector<FastBitVector, 0, UnsafeVectorOverflow> m_usesBefore; Vector<FastBitVector, 0, UnsafeVectorOverflow> m_usesAfter; }; } // namespace JSC