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Diffstat (limited to 'chromium/third_party/WebKit/Source/wtf/QuantizedAllocation.h')
-rw-r--r-- | chromium/third_party/WebKit/Source/wtf/QuantizedAllocation.h | 85 |
1 files changed, 0 insertions, 85 deletions
diff --git a/chromium/third_party/WebKit/Source/wtf/QuantizedAllocation.h b/chromium/third_party/WebKit/Source/wtf/QuantizedAllocation.h deleted file mode 100644 index 59de8e7077a..00000000000 --- a/chromium/third_party/WebKit/Source/wtf/QuantizedAllocation.h +++ /dev/null @@ -1,85 +0,0 @@ -/* - * Copyright (C) 2013 Google 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: - * - * * Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * * 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. - * * Neither the name of Google Inc. nor the names of its - * contributors may be used to endorse or promote products derived from - * this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT - * OWNER 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 WTF_QuantizedAllocation_h -#define WTF_QuantizedAllocation_h - -// DESCRIPTION -// QuantizedAllocation::quantizedSize() rounds up the specific size such that: -// 1) Granularity of allocation sizes is >1, and grows as a fraction of the -// allocation size. This property can be used to limit bucket fragmentation -// when sitting on top of a high-granularity allocator such as PartitionAlloc. -// 2) The sizes are likely (but not guaranteed) to correspond to exact "bucket -// sizes" of any underlying allocator that implements standard bucketing. -// This currently includes tcmalloc, Windows LFH and PartitionAlloc. - -#include "wtf/WTFExport.h" -#include <limits.h> - -namespace WTF { - -class WTF_EXPORT QuantizedAllocation { -public: - // Allocations above 32k are rounded to 4k (which is typically the system - // page size). - static const size_t kMaxAllocation = 32768; - static const size_t kMaxRounding = 4096; - - // This is the minimum granularity of allocation, currently 8 bytes. - static const size_t kMinRounding = 8; - - // After 128 bytes, the granularity doubles, and proceeds to double again - // as the allocation size further doubles. - static const size_t kMinRoundingLimit = 128; - static const size_t kTableSize = kMaxAllocation / kMinRoundingLimit; - - // Using "unsigned" is not a limitation because Chromium's max malloc() is - // 2GB even on 64-bit. - static const size_t kMaxUnquantizedAllocation = INT_MAX - kMaxRounding; - - static void init(); - - static size_t quantizedSize(size_t size) - { - size_t roundToLessOne; - if (UNLIKELY(size >= kMaxAllocation)) - roundToLessOne = kMaxRounding - 1; - else - roundToLessOne = table[size / kMinRoundingLimit]; - return (size + roundToLessOne) & ~roundToLessOne; - } - -private: - static unsigned short table[kTableSize]; -}; - -} // namespace WTF - -#endif // WTF_QuantizedAllocation_h |