Magic-Mirror/gecko-dev
1
0
Fork 0
mirror of https://github.com/mozilla/gecko-dev.git synced 2024-10-23 10:15:41 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Bug 1592992 - Part 7: Split bit-array functions from jsutil.h. r=jonco

Browse Source 
Differential Revision: https://phabricator.services.mozilla.com/D51366

--HG--
rename : js/src/jsutil.h => js/src/util/BitArray.h
extra : moz-landing-system : lando
This commit is contained in:
André Bargull 2019-11-08 11:05:14 +00:00
parent 0b2f713a4a
commit 5b0689fff8
2 changed files with 72 additions and 50 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

51
js/src/jsutil.h
View File

@ -22,6 +22,7 @@
#include "js/Initialization.h"
#include "js/Utility.h"
#include "js/Value.h"
#include "util/BitArray.h"
#include "util/Poison.h"
/* Crash diagnostics by default in debug and on nightly channel. */
@ -88,56 +89,6 @@ static constexpr T AlignBytes(T bytes, U alignment) {
/*****************************************************************************/
/* A bit array is an array of bits represented by an array of words (size_t). */
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;
}
}
// Placement-new elements of an array. This should optimize away for types with
// trivial default initiation.
template <typename T>

71
js/src/util/BitArray.h Normal file
View File

@ -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 */