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-rw-r--r--js/src/ds/Bitmap.cpp113
1 files changed, 113 insertions, 0 deletions
diff --git a/js/src/ds/Bitmap.cpp b/js/src/ds/Bitmap.cpp
new file mode 100644
index 0000000000..d96cf67c71
--- /dev/null
+++ b/js/src/ds/Bitmap.cpp
@@ -0,0 +1,113 @@
+/* -*- 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/. */
+
+#include "ds/Bitmap.h"
+
+#include <algorithm>
+
+#include "js/UniquePtr.h"
+
+using namespace js;
+
+SparseBitmap::~SparseBitmap() {
+ for (Data::Range r(data.all()); !r.empty(); r.popFront()) {
+ js_delete(r.front().value());
+ }
+}
+
+size_t SparseBitmap::sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) {
+ size_t size = data.shallowSizeOfExcludingThis(mallocSizeOf);
+ for (Data::Range r(data.all()); !r.empty(); r.popFront()) {
+ size += mallocSizeOf(r.front().value());
+ }
+ return size;
+}
+
+SparseBitmap::BitBlock* SparseBitmap::createBlock(Data::AddPtr p,
+ size_t blockId) {
+ MOZ_ASSERT(!p);
+ auto block = js::MakeUnique<BitBlock>();
+ if (!block || !data.add(p, blockId, block.get())) {
+ return nullptr;
+ }
+ std::fill(block->begin(), block->end(), 0);
+ return block.release();
+}
+
+SparseBitmap::BitBlock& SparseBitmap::createBlock(
+ Data::AddPtr p, size_t blockId, AutoEnterOOMUnsafeRegion& oomUnsafe) {
+ BitBlock* block = createBlock(p, blockId);
+ if (!block) {
+ oomUnsafe.crash("Bitmap OOM");
+ }
+ return *block;
+}
+
+bool SparseBitmap::getBit(size_t bit) const {
+ size_t word = bit / JS_BITS_PER_WORD;
+ size_t blockWord = blockStartWord(word);
+
+ const BitBlock* block = getBlock(blockWord / WordsInBlock);
+ if (block) {
+ return (*block)[word - blockWord] & bitMask(bit);
+ }
+ return false;
+}
+
+bool SparseBitmap::readonlyThreadsafeGetBit(size_t bit) const {
+ size_t word = bit / JS_BITS_PER_WORD;
+ size_t blockWord = blockStartWord(word);
+
+ const BitBlock* block = readonlyThreadsafeGetBlock(blockWord / WordsInBlock);
+ if (block) {
+ return (*block)[word - blockWord] & bitMask(bit);
+ }
+ return false;
+}
+
+void SparseBitmap::bitwiseAndWith(const DenseBitmap& other) {
+ for (Data::Enum e(data); !e.empty(); e.popFront()) {
+ BitBlock& block = *e.front().value();
+ size_t blockWord = e.front().key() * WordsInBlock;
+ bool anySet = false;
+ size_t numWords = wordIntersectCount(blockWord, other);
+ for (size_t i = 0; i < numWords; i++) {
+ block[i] &= other.word(blockWord + i);
+ anySet |= !!block[i];
+ }
+ if (!anySet) {
+ js_delete(&block);
+ e.removeFront();
+ }
+ }
+}
+
+void SparseBitmap::bitwiseOrWith(const SparseBitmap& other) {
+ for (Data::Range r(other.data.all()); !r.empty(); r.popFront()) {
+ const BitBlock& otherBlock = *r.front().value();
+ BitBlock& block = getOrCreateBlock(r.front().key());
+ for (size_t i = 0; i < WordsInBlock; i++) {
+ block[i] |= otherBlock[i];
+ }
+ }
+}
+
+void SparseBitmap::bitwiseOrInto(DenseBitmap& other) const {
+ for (Data::Range r(data.all()); !r.empty(); r.popFront()) {
+ BitBlock& block = *r.front().value();
+ size_t blockWord = r.front().key() * WordsInBlock;
+ size_t numWords = wordIntersectCount(blockWord, other);
+#ifdef DEBUG
+ // Any words out of range in other should be zero in this bitmap.
+ for (size_t i = numWords; i < WordsInBlock; i++) {
+ MOZ_ASSERT(!block[i]);
+ }
+#endif
+ for (size_t i = 0; i < numWords; i++) {
+ other.word(blockWord + i) |= block[i];
+ }
+ }
+}