/* * Copyright (C) 2014-2019 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. ``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 * 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. */ #ifndef BumpAllocator_h #define BumpAllocator_h #include "BAssert.h" #include "BumpRange.h" #include "ObjectType.h" namespace bmalloc { // Helper object for allocating small objects. class BumpAllocator { public: BumpAllocator(); void init(size_t); size_t size() { return m_size; } bool isNull() { return !m_ptr; } void clear(); bool canAllocate() { return !!m_remaining; } void* allocate(); void refill(const BumpRange&); private: char* m_ptr; unsigned m_size; unsigned m_remaining; }; inline BumpAllocator::BumpAllocator() : m_ptr() , m_size() , m_remaining() { } inline void BumpAllocator::init(size_t size) { m_ptr = nullptr; m_size = size; m_remaining = 0; } inline void* BumpAllocator::allocate() { BASSERT(m_remaining); --m_remaining; char* result = m_ptr; m_ptr += m_size; return result; } inline void BumpAllocator::refill(const BumpRange& bumpRange) { BASSERT(!canAllocate()); m_ptr = bumpRange.begin; m_remaining = bumpRange.objectCount; BASSERT(canAllocate()); } inline void BumpAllocator::clear() { m_ptr = nullptr; m_remaining = 0; } } // namespace bmalloc #endif // BumpAllocator_h