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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
commit | 26a029d407be480d791972afb5975cf62c9360a6 (patch) | |
tree | f435a8308119effd964b339f76abb83a57c29483 /js/src/util/BitArray.h | |
parent | Initial commit. (diff) | |
download | firefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz firefox-26a029d407be480d791972afb5975cf62c9360a6.zip |
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | js/src/util/BitArray.h | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/js/src/util/BitArray.h b/js/src/util/BitArray.h new file mode 100644 index 0000000000..ca83d8d0df --- /dev/null +++ b/js/src/util/BitArray.h @@ -0,0 +1,71 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- + * vim: set ts=8 sts=2 et sw=2 tw=80: + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * A bit array is an array of bits represented by an array of words (size_t). + */ + +#ifndef util_BitArray_h +#define util_BitArray_h + +#include "mozilla/Assertions.h" + +#include <limits.h> +#include <stddef.h> + +namespace js { + +static const size_t BitArrayElementBits = sizeof(size_t) * CHAR_BIT; + +static inline unsigned NumWordsForBitArrayOfLength(size_t length) { + return (length + (BitArrayElementBits - 1)) / BitArrayElementBits; +} + +static inline unsigned BitArrayIndexToWordIndex(size_t length, + size_t bitIndex) { + unsigned wordIndex = bitIndex / BitArrayElementBits; + MOZ_ASSERT(wordIndex < length); + return wordIndex; +} + +static inline size_t BitArrayIndexToWordMask(size_t i) { + return size_t(1) << (i % BitArrayElementBits); +} + +static inline bool IsBitArrayElementSet(const size_t* array, size_t length, + size_t i) { + return array[BitArrayIndexToWordIndex(length, i)] & + BitArrayIndexToWordMask(i); +} + +static inline bool IsAnyBitArrayElementSet(const size_t* array, size_t length) { + unsigned numWords = NumWordsForBitArrayOfLength(length); + for (unsigned i = 0; i < numWords; ++i) { + if (array[i]) { + return true; + } + } + return false; +} + +static inline void SetBitArrayElement(size_t* array, size_t length, size_t i) { + array[BitArrayIndexToWordIndex(length, i)] |= BitArrayIndexToWordMask(i); +} + +static inline void ClearBitArrayElement(size_t* array, size_t length, + size_t i) { + array[BitArrayIndexToWordIndex(length, i)] &= ~BitArrayIndexToWordMask(i); +} + +static inline void ClearAllBitArrayElements(size_t* array, size_t length) { + for (unsigned i = 0; i < length; ++i) { + array[i] = 0; + } +} + +} /* namespace js */ + +#endif /* util_BitArray_h */ |