summaryrefslogtreecommitdiffstats
path: root/mfbt/Vector.h
diff options
context:
space:
mode:
Diffstat (limited to 'mfbt/Vector.h')
-rw-r--r--mfbt/Vector.h1653
1 files changed, 1653 insertions, 0 deletions
diff --git a/mfbt/Vector.h b/mfbt/Vector.h
new file mode 100644
index 0000000000..380e272548
--- /dev/null
+++ b/mfbt/Vector.h
@@ -0,0 +1,1653 @@
+/* -*- 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 type/length-parametrized vector class. */
+
+#ifndef mozilla_Vector_h
+#define mozilla_Vector_h
+
+#include <new> // for placement new
+#include <type_traits>
+#include <utility>
+
+#include "mozilla/Alignment.h"
+#include "mozilla/AllocPolicy.h"
+#include "mozilla/ArrayUtils.h" // for PointerRangeSize
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/MathAlgorithms.h"
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/OperatorNewExtensions.h"
+#include "mozilla/ReentrancyGuard.h"
+#include "mozilla/Span.h"
+#include "mozilla/TemplateLib.h"
+
+namespace mozilla {
+
+template <typename T, size_t N, class AllocPolicy>
+class Vector;
+
+namespace detail {
+
+/*
+ * Check that the given capacity wastes the minimal amount of space if
+ * allocated on the heap. This means that aCapacity*EltSize is as close to a
+ * power-of-two as possible. growStorageBy() is responsible for ensuring this.
+ */
+template <size_t EltSize>
+static bool CapacityHasExcessSpace(size_t aCapacity) {
+ size_t size = aCapacity * EltSize;
+ return RoundUpPow2(size) - size >= EltSize;
+}
+
+/*
+ * AllocPolicy can optionally provide a `computeGrowth<T>(size_t aOldElts,
+ * size_t aIncr)` method that returns the new number of elements to allocate
+ * when the current capacity is `aOldElts` and `aIncr` more are being
+ * requested. If the AllocPolicy does not have such a method, a fallback
+ * will be used that mostly will just round the new requested capacity up to
+ * the next power of two, which results in doubling capacity for the most part.
+ *
+ * If the new size would overflow some limit, `computeGrowth` returns 0.
+ *
+ * A simpler way would be to make computeGrowth() part of the API for all
+ * AllocPolicy classes, but this turns out to be rather complex because
+ * mozalloc.h defines a very widely-used InfallibleAllocPolicy, and yet it
+ * can only be compiled in limited contexts, eg within `extern "C"` and with
+ * -std=c++11 rather than a later version. That makes the headers that are
+ * necessary for the computation unavailable (eg mfbt/MathAlgorithms.h).
+ */
+
+// Fallback version.
+template <size_t EltSize>
+inline size_t GrowEltsByDoubling(size_t aOldElts, size_t aIncr) {
+ /*
+ * When choosing a new capacity, its size in bytes should is as close to 2**N
+ * bytes as possible. 2**N-sized requests are best because they are unlikely
+ * to be rounded up by the allocator. Asking for a 2**N number of elements
+ * isn't as good, because if EltSize is not a power-of-two that would
+ * result in a non-2**N request size.
+ */
+
+ if (aIncr == 1) {
+ if (aOldElts == 0) {
+ return 1;
+ }
+
+ /* This case occurs in ~15--20% of the calls to Vector::growStorageBy. */
+
+ /*
+ * Will aOldSize * 4 * sizeof(T) overflow? This condition limits a
+ * collection to 1GB of memory on a 32-bit system, which is a reasonable
+ * limit. It also ensures that
+ *
+ * static_cast<char*>(end()) - static_cast<char*>(begin())
+ *
+ * for a Vector doesn't overflow ptrdiff_t (see bug 510319).
+ */
+ if (MOZ_UNLIKELY(aOldElts &
+ mozilla::tl::MulOverflowMask<4 * EltSize>::value)) {
+ return 0;
+ }
+
+ /*
+ * If we reach here, the existing capacity will have a size that is already
+ * as close to 2^N as sizeof(T) will allow. Just double the capacity, and
+ * then there might be space for one more element.
+ */
+ size_t newElts = aOldElts * 2;
+ if (CapacityHasExcessSpace<EltSize>(newElts)) {
+ newElts += 1;
+ }
+ return newElts;
+ }
+
+ /* This case occurs in ~2% of the calls to Vector::growStorageBy. */
+ size_t newMinCap = aOldElts + aIncr;
+
+ /* Did aOldElts + aIncr overflow? Will newMinCap * EltSize rounded up to the
+ * next power of two overflow PTRDIFF_MAX? */
+ if (MOZ_UNLIKELY(newMinCap < aOldElts ||
+ newMinCap & tl::MulOverflowMask<4 * EltSize>::value)) {
+ return 0;
+ }
+
+ size_t newMinSize = newMinCap * EltSize;
+ size_t newSize = RoundUpPow2(newMinSize);
+ return newSize / EltSize;
+};
+
+// Fallback version.
+template <typename AP, size_t EltSize>
+static size_t ComputeGrowth(size_t aOldElts, size_t aIncr, int) {
+ return GrowEltsByDoubling<EltSize>(aOldElts, aIncr);
+}
+
+// If the AllocPolicy provides its own computeGrowth<EltSize> implementation,
+// use that.
+template <typename AP, size_t EltSize>
+static size_t ComputeGrowth(
+ size_t aOldElts, size_t aIncr,
+ decltype(std::declval<AP>().template computeGrowth<EltSize>(0, 0),
+ bool()) aOverloadSelector) {
+ size_t newElts = AP::template computeGrowth<EltSize>(aOldElts, aIncr);
+ MOZ_ASSERT(newElts <= PTRDIFF_MAX && newElts * EltSize <= PTRDIFF_MAX,
+ "invalid Vector size (see bug 510319)");
+ return newElts;
+}
+
+/*
+ * This template class provides a default implementation for vector operations
+ * when the element type is not known to be a POD, as judged by IsPod.
+ */
+template <typename T, size_t N, class AP, bool IsPod>
+struct VectorImpl {
+ /*
+ * Constructs an object in the uninitialized memory at *aDst with aArgs.
+ */
+ template <typename... Args>
+ MOZ_NONNULL(1)
+ static inline void new_(T* aDst, Args&&... aArgs) {
+ new (KnownNotNull, aDst) T(std::forward<Args>(aArgs)...);
+ }
+
+ /* Destroys constructed objects in the range [aBegin, aEnd). */
+ static inline void destroy(T* aBegin, T* aEnd) {
+ MOZ_ASSERT(aBegin <= aEnd);
+ for (T* p = aBegin; p < aEnd; ++p) {
+ p->~T();
+ }
+ }
+
+ /* Constructs objects in the uninitialized range [aBegin, aEnd). */
+ static inline void initialize(T* aBegin, T* aEnd) {
+ MOZ_ASSERT(aBegin <= aEnd);
+ for (T* p = aBegin; p < aEnd; ++p) {
+ new_(p);
+ }
+ }
+
+ /*
+ * Copy-constructs objects in the uninitialized range
+ * [aDst, aDst+(aSrcEnd-aSrcStart)) from the range [aSrcStart, aSrcEnd).
+ */
+ template <typename U>
+ static inline void copyConstruct(T* aDst, const U* aSrcStart,
+ const U* aSrcEnd) {
+ MOZ_ASSERT(aSrcStart <= aSrcEnd);
+ for (const U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) {
+ new_(aDst, *p);
+ }
+ }
+
+ /*
+ * Move-constructs objects in the uninitialized range
+ * [aDst, aDst+(aSrcEnd-aSrcStart)) from the range [aSrcStart, aSrcEnd).
+ */
+ template <typename U>
+ static inline void moveConstruct(T* aDst, U* aSrcStart, U* aSrcEnd) {
+ MOZ_ASSERT(aSrcStart <= aSrcEnd);
+ for (U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) {
+ new_(aDst, std::move(*p));
+ }
+ }
+
+ /*
+ * Copy-constructs objects in the uninitialized range [aDst, aDst+aN) from
+ * the same object aU.
+ */
+ template <typename U>
+ static inline void copyConstructN(T* aDst, size_t aN, const U& aU) {
+ for (T* end = aDst + aN; aDst < end; ++aDst) {
+ new_(aDst, aU);
+ }
+ }
+
+ /*
+ * Grows the given buffer to have capacity aNewCap, preserving the objects
+ * constructed in the range [begin, end) and updating aV. Assumes that (1)
+ * aNewCap has not overflowed, and (2) multiplying aNewCap by sizeof(T) will
+ * not overflow.
+ */
+ [[nodiscard]] static inline bool growTo(Vector<T, N, AP>& aV,
+ size_t aNewCap) {
+ MOZ_ASSERT(!aV.usingInlineStorage());
+ MOZ_ASSERT(!CapacityHasExcessSpace<sizeof(T)>(aNewCap));
+ T* newbuf = aV.template pod_malloc<T>(aNewCap);
+ if (MOZ_UNLIKELY(!newbuf)) {
+ return false;
+ }
+ T* dst = newbuf;
+ T* src = aV.beginNoCheck();
+ for (; src < aV.endNoCheck(); ++dst, ++src) {
+ new_(dst, std::move(*src));
+ }
+ VectorImpl::destroy(aV.beginNoCheck(), aV.endNoCheck());
+ aV.free_(aV.mBegin, aV.mTail.mCapacity);
+ aV.mBegin = newbuf;
+ /* aV.mLength is unchanged. */
+ aV.mTail.mCapacity = aNewCap;
+ return true;
+ }
+};
+
+/*
+ * This partial template specialization provides a default implementation for
+ * vector operations when the element type is known to be a POD, as judged by
+ * IsPod.
+ */
+template <typename T, size_t N, class AP>
+struct VectorImpl<T, N, AP, true> {
+ template <typename... Args>
+ MOZ_NONNULL(1)
+ static inline void new_(T* aDst, Args&&... aArgs) {
+ // Explicitly construct a local object instead of using a temporary since
+ // T(args...) will be treated like a C-style cast in the unary case and
+ // allow unsafe conversions. Both forms should be equivalent to an
+ // optimizing compiler.
+ T temp(std::forward<Args>(aArgs)...);
+ *aDst = temp;
+ }
+
+ static inline void destroy(T*, T*) {}
+
+ static inline void initialize(T* aBegin, T* aEnd) {
+ /*
+ * You would think that memset would be a big win (or even break even)
+ * when we know T is a POD. But currently it's not. This is probably
+ * because |append| tends to be given small ranges and memset requires
+ * a function call that doesn't get inlined.
+ *
+ * memset(aBegin, 0, sizeof(T) * (aEnd - aBegin));
+ */
+ MOZ_ASSERT(aBegin <= aEnd);
+ for (T* p = aBegin; p < aEnd; ++p) {
+ new_(p);
+ }
+ }
+
+ template <typename U>
+ static inline void copyConstruct(T* aDst, const U* aSrcStart,
+ const U* aSrcEnd) {
+ /*
+ * See above memset comment. Also, notice that copyConstruct is
+ * currently templated (T != U), so memcpy won't work without
+ * requiring T == U.
+ *
+ * memcpy(aDst, aSrcStart, sizeof(T) * (aSrcEnd - aSrcStart));
+ */
+ MOZ_ASSERT(aSrcStart <= aSrcEnd);
+ for (const U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) {
+ new_(aDst, *p);
+ }
+ }
+
+ template <typename U>
+ static inline void moveConstruct(T* aDst, const U* aSrcStart,
+ const U* aSrcEnd) {
+ copyConstruct(aDst, aSrcStart, aSrcEnd);
+ }
+
+ static inline void copyConstructN(T* aDst, size_t aN, const T& aT) {
+ for (T* end = aDst + aN; aDst < end; ++aDst) {
+ new_(aDst, aT);
+ }
+ }
+
+ [[nodiscard]] static inline bool growTo(Vector<T, N, AP>& aV,
+ size_t aNewCap) {
+ MOZ_ASSERT(!aV.usingInlineStorage());
+ MOZ_ASSERT(!CapacityHasExcessSpace<sizeof(T)>(aNewCap));
+ T* newbuf =
+ aV.template pod_realloc<T>(aV.mBegin, aV.mTail.mCapacity, aNewCap);
+ if (MOZ_UNLIKELY(!newbuf)) {
+ return false;
+ }
+ aV.mBegin = newbuf;
+ /* aV.mLength is unchanged. */
+ aV.mTail.mCapacity = aNewCap;
+ return true;
+ }
+};
+
+// A struct for TestVector.cpp to access private internal fields.
+// DO NOT DEFINE IN YOUR OWN CODE.
+struct VectorTesting;
+
+} // namespace detail
+
+/*
+ * STL-like container providing a short-lived, dynamic buffer. Vector calls the
+ * constructors/destructors of all elements stored in its internal buffer, so
+ * non-PODs may be safely used. Additionally, Vector will store the first N
+ * elements in-place before resorting to dynamic allocation.
+ *
+ * T requirements:
+ * - default and copy constructible, assignable, destructible
+ * - operations do not throw
+ * MinInlineCapacity requirements:
+ * - any value, however, MinInlineCapacity is clamped to min/max values
+ * AllocPolicy:
+ * - see "Allocation policies" in AllocPolicy.h (defaults to
+ * mozilla::MallocAllocPolicy)
+ *
+ * Vector is not reentrant: T member functions called during Vector member
+ * functions must not call back into the same object!
+ */
+template <typename T, size_t MinInlineCapacity = 0,
+ class AllocPolicy = MallocAllocPolicy>
+class MOZ_NON_PARAM Vector final : private AllocPolicy {
+ /* utilities */
+ static constexpr bool kElemIsPod =
+ std::is_trivial_v<T> && std::is_standard_layout_v<T>;
+ typedef detail::VectorImpl<T, MinInlineCapacity, AllocPolicy, kElemIsPod>
+ Impl;
+ friend struct detail::VectorImpl<T, MinInlineCapacity, AllocPolicy,
+ kElemIsPod>;
+
+ friend struct detail::VectorTesting;
+
+ [[nodiscard]] bool growStorageBy(size_t aIncr);
+ [[nodiscard]] bool convertToHeapStorage(size_t aNewCap);
+ [[nodiscard]] bool maybeCheckSimulatedOOM(size_t aRequestedSize);
+
+ /* magic constants */
+
+ /**
+ * The maximum space allocated for inline element storage.
+ *
+ * We reduce space by what the AllocPolicy base class and prior Vector member
+ * fields likely consume to attempt to play well with binary size classes.
+ */
+ static constexpr size_t kMaxInlineBytes =
+ 1024 -
+ (sizeof(AllocPolicy) + sizeof(T*) + sizeof(size_t) + sizeof(size_t));
+
+ /**
+ * The number of T elements of inline capacity built into this Vector. This
+ * is usually |MinInlineCapacity|, but it may be less (or zero!) for large T.
+ *
+ * We use a partially-specialized template (not explicit specialization, which
+ * is only allowed at namespace scope) to compute this value. The benefit is
+ * that |sizeof(T)| need not be computed, and |T| doesn't have to be fully
+ * defined at the time |Vector<T>| appears, if no inline storage is requested.
+ */
+ template <size_t MinimumInlineCapacity, size_t Dummy>
+ struct ComputeCapacity {
+ static constexpr size_t value =
+ tl::Min<MinimumInlineCapacity, kMaxInlineBytes / sizeof(T)>::value;
+ };
+
+ template <size_t Dummy>
+ struct ComputeCapacity<0, Dummy> {
+ static constexpr size_t value = 0;
+ };
+
+ /** The actual inline capacity in number of elements T. This may be zero! */
+ static constexpr size_t kInlineCapacity =
+ ComputeCapacity<MinInlineCapacity, 0>::value;
+
+ /* member data */
+
+ /*
+ * Pointer to the buffer, be it inline or heap-allocated. Only [mBegin,
+ * mBegin + mLength) hold valid constructed T objects. The range [mBegin +
+ * mLength, mBegin + mCapacity) holds uninitialized memory. The range
+ * [mBegin + mLength, mBegin + mReserved) also holds uninitialized memory
+ * previously allocated by a call to reserve().
+ */
+ T* mBegin;
+
+ /* Number of elements in the vector. */
+ size_t mLength;
+
+ /*
+ * Memory used to store capacity, reserved element count (debug builds only),
+ * and inline storage. The simple "answer" is:
+ *
+ * size_t mCapacity;
+ * #ifdef DEBUG
+ * size_t mReserved;
+ * #endif
+ * alignas(T) unsigned char mBytes[kInlineCapacity * sizeof(T)];
+ *
+ * but there are complications. First, C++ forbids zero-sized arrays that
+ * might result. Second, we don't want zero capacity to affect Vector's size
+ * (even empty classes take up a byte, unless they're base classes).
+ *
+ * Yet again, we eliminate the zero-sized array using partial specialization.
+ * And we eliminate potential size hit by putting capacity/reserved in one
+ * struct, then putting the array (if any) in a derived struct. If no array
+ * is needed, the derived struct won't consume extra space.
+ */
+ struct CapacityAndReserved {
+ explicit CapacityAndReserved(size_t aCapacity, size_t aReserved)
+ : mCapacity(aCapacity)
+#ifdef DEBUG
+ ,
+ mReserved(aReserved)
+#endif
+ {
+ }
+ CapacityAndReserved() = default;
+
+ /* Max number of elements storable in the vector without resizing. */
+ size_t mCapacity;
+
+#ifdef DEBUG
+ /* Max elements of reserved or used space in this vector. */
+ size_t mReserved;
+#endif
+ };
+
+// Silence warnings about this struct possibly being padded dued to the
+// alignas() in it -- there's nothing we can do to avoid it.
+#ifdef _MSC_VER
+# pragma warning(push)
+# pragma warning(disable : 4324)
+#endif // _MSC_VER
+
+ template <size_t Capacity, size_t Dummy>
+ struct CRAndStorage : CapacityAndReserved {
+ explicit CRAndStorage(size_t aCapacity, size_t aReserved)
+ : CapacityAndReserved(aCapacity, aReserved) {}
+ CRAndStorage() = default;
+
+ alignas(T) unsigned char mBytes[Capacity * sizeof(T)];
+
+ // GCC fails due to -Werror=strict-aliasing if |mBytes| is directly cast to
+ // T*. Indirecting through this function addresses the problem.
+ void* data() { return mBytes; }
+
+ T* storage() { return static_cast<T*>(data()); }
+ };
+
+ template <size_t Dummy>
+ struct CRAndStorage<0, Dummy> : CapacityAndReserved {
+ explicit CRAndStorage(size_t aCapacity, size_t aReserved)
+ : CapacityAndReserved(aCapacity, aReserved) {}
+ CRAndStorage() = default;
+
+ T* storage() {
+ // If this returns |nullptr|, functions like |Vector::begin()| would too,
+ // breaking callers that pass a vector's elements as pointer/length to
+ // code that bounds its operation by length but (even just as a sanity
+ // check) always wants a non-null pointer. Fake up an aligned, non-null
+ // pointer to support these callers.
+ return reinterpret_cast<T*>(sizeof(T));
+ }
+ };
+
+ CRAndStorage<kInlineCapacity, 0> mTail;
+
+#ifdef _MSC_VER
+# pragma warning(pop)
+#endif // _MSC_VER
+
+#ifdef DEBUG
+ friend class ReentrancyGuard;
+ bool mEntered;
+#endif
+
+ /* private accessors */
+
+ bool usingInlineStorage() const {
+ return mBegin == const_cast<Vector*>(this)->inlineStorage();
+ }
+
+ T* inlineStorage() { return mTail.storage(); }
+
+ T* beginNoCheck() const { return mBegin; }
+
+ T* endNoCheck() { return mBegin + mLength; }
+
+ const T* endNoCheck() const { return mBegin + mLength; }
+
+#ifdef DEBUG
+ /**
+ * The amount of explicitly allocated space in this vector that is immediately
+ * available to be filled by appending additional elements. This value is
+ * always greater than or equal to |length()| -- the vector's actual elements
+ * are implicitly reserved. This value is always less than or equal to
+ * |capacity()|. It may be explicitly increased using the |reserve()| method.
+ */
+ size_t reserved() const {
+ MOZ_ASSERT(mLength <= mTail.mReserved);
+ MOZ_ASSERT(mTail.mReserved <= mTail.mCapacity);
+ return mTail.mReserved;
+ }
+#endif
+
+ bool internalEnsureCapacity(size_t aNeeded);
+
+ /* Append operations guaranteed to succeed due to pre-reserved space. */
+ template <typename U>
+ void internalAppend(U&& aU);
+ template <typename U, size_t O, class BP>
+ void internalAppendAll(const Vector<U, O, BP>& aU);
+ void internalAppendN(const T& aT, size_t aN);
+ template <typename U>
+ void internalAppend(const U* aBegin, size_t aLength);
+ template <typename U>
+ void internalMoveAppend(U* aBegin, size_t aLength);
+
+ public:
+ static const size_t sMaxInlineStorage = MinInlineCapacity;
+
+ typedef T ElementType;
+
+ explicit Vector(AllocPolicy);
+ Vector() : Vector(AllocPolicy()) {}
+
+ Vector(Vector&&); /* Move constructor. */
+ Vector& operator=(Vector&&); /* Move assignment. */
+ ~Vector();
+
+ /* accessors */
+
+ const AllocPolicy& allocPolicy() const { return *this; }
+
+ AllocPolicy& allocPolicy() { return *this; }
+
+ enum { InlineLength = MinInlineCapacity };
+
+ size_t length() const { return mLength; }
+
+ bool empty() const { return mLength == 0; }
+
+ size_t capacity() const { return mTail.mCapacity; }
+
+ T* begin() {
+ MOZ_ASSERT(!mEntered);
+ return mBegin;
+ }
+
+ const T* begin() const {
+ MOZ_ASSERT(!mEntered);
+ return mBegin;
+ }
+
+ T* end() {
+ MOZ_ASSERT(!mEntered);
+ return mBegin + mLength;
+ }
+
+ const T* end() const {
+ MOZ_ASSERT(!mEntered);
+ return mBegin + mLength;
+ }
+
+ T& operator[](size_t aIndex) {
+ MOZ_ASSERT(!mEntered);
+ MOZ_ASSERT(aIndex < mLength);
+ return begin()[aIndex];
+ }
+
+ const T& operator[](size_t aIndex) const {
+ MOZ_ASSERT(!mEntered);
+ MOZ_ASSERT(aIndex < mLength);
+ return begin()[aIndex];
+ }
+
+ T& back() {
+ MOZ_ASSERT(!mEntered);
+ MOZ_ASSERT(!empty());
+ return *(end() - 1);
+ }
+
+ const T& back() const {
+ MOZ_ASSERT(!mEntered);
+ MOZ_ASSERT(!empty());
+ return *(end() - 1);
+ }
+
+ operator mozilla::Span<const T>() const {
+ // Explicitly specify template argument here to avoid instantiating Span<T>
+ // first and then implicitly converting to Span<const T>
+ return mozilla::Span<const T>{mBegin, mLength};
+ }
+
+ operator mozilla::Span<T>() { return mozilla::Span{mBegin, mLength}; }
+
+ class Range {
+ friend class Vector;
+ T* mCur;
+ T* mEnd;
+ Range(T* aCur, T* aEnd) : mCur(aCur), mEnd(aEnd) {
+ MOZ_ASSERT(aCur <= aEnd);
+ }
+
+ public:
+ bool empty() const { return mCur == mEnd; }
+ size_t remain() const { return PointerRangeSize(mCur, mEnd); }
+ T& front() const {
+ MOZ_ASSERT(!empty());
+ return *mCur;
+ }
+ void popFront() {
+ MOZ_ASSERT(!empty());
+ ++mCur;
+ }
+ T popCopyFront() {
+ MOZ_ASSERT(!empty());
+ return *mCur++;
+ }
+ };
+
+ class ConstRange {
+ friend class Vector;
+ const T* mCur;
+ const T* mEnd;
+ ConstRange(const T* aCur, const T* aEnd) : mCur(aCur), mEnd(aEnd) {
+ MOZ_ASSERT(aCur <= aEnd);
+ }
+
+ public:
+ bool empty() const { return mCur == mEnd; }
+ size_t remain() const { return PointerRangeSize(mCur, mEnd); }
+ const T& front() const {
+ MOZ_ASSERT(!empty());
+ return *mCur;
+ }
+ void popFront() {
+ MOZ_ASSERT(!empty());
+ ++mCur;
+ }
+ T popCopyFront() {
+ MOZ_ASSERT(!empty());
+ return *mCur++;
+ }
+ };
+
+ Range all() { return Range(begin(), end()); }
+ ConstRange all() const { return ConstRange(begin(), end()); }
+
+ /* mutators */
+
+ /**
+ * Reverse the order of the elements in the vector in place.
+ */
+ void reverse();
+
+ /**
+ * Given that the vector is empty, grow the internal capacity to |aRequest|,
+ * keeping the length 0.
+ */
+ [[nodiscard]] bool initCapacity(size_t aRequest);
+
+ /**
+ * Given that the vector is empty, grow the internal capacity and length to
+ * |aRequest| leaving the elements' memory completely uninitialized (with all
+ * the associated hazards and caveats). This avoids the usual allocation-size
+ * rounding that happens in resize and overhead of initialization for elements
+ * that are about to be overwritten.
+ */
+ [[nodiscard]] bool initLengthUninitialized(size_t aRequest);
+
+ /**
+ * If reserve(aRequest) succeeds and |aRequest >= length()|, then appending
+ * |aRequest - length()| elements, in any sequence of append/appendAll calls,
+ * is guaranteed to succeed.
+ *
+ * A request to reserve an amount less than the current length does not affect
+ * reserved space.
+ */
+ [[nodiscard]] bool reserve(size_t aRequest);
+
+ /**
+ * Destroy elements in the range [end() - aIncr, end()). Does not deallocate
+ * or unreserve storage for those elements.
+ */
+ void shrinkBy(size_t aIncr);
+
+ /**
+ * Destroy elements in the range [aNewLength, end()). Does not deallocate
+ * or unreserve storage for those elements.
+ */
+ void shrinkTo(size_t aNewLength);
+
+ /** Grow the vector by aIncr elements. */
+ [[nodiscard]] bool growBy(size_t aIncr);
+
+ /** Call shrinkBy or growBy based on whether newSize > length(). */
+ [[nodiscard]] bool resize(size_t aNewLength);
+
+ /**
+ * Increase the length of the vector, but don't initialize the new elements
+ * -- leave them as uninitialized memory.
+ */
+ [[nodiscard]] bool growByUninitialized(size_t aIncr);
+ void infallibleGrowByUninitialized(size_t aIncr);
+ [[nodiscard]] bool resizeUninitialized(size_t aNewLength);
+
+ /** Shorthand for shrinkBy(length()). */
+ void clear();
+
+ /** Clears and releases any heap-allocated storage. */
+ void clearAndFree();
+
+ /**
+ * Shrinks the storage to drop excess capacity if possible.
+ *
+ * The return value indicates whether the operation succeeded, otherwise, it
+ * represents an OOM. The bool can be safely ignored unless you want to
+ * provide the guarantee that `length() == capacity()`.
+ *
+ * For PODs, it calls the AllocPolicy's pod_realloc. For non-PODs, it moves
+ * the elements into the new storage.
+ */
+ bool shrinkStorageToFit();
+
+ /**
+ * If true, appending |aNeeded| elements won't reallocate elements storage.
+ * This *doesn't* mean that infallibleAppend may be used! You still must
+ * reserve the extra space, even if this method indicates that appends won't
+ * need to reallocate elements storage.
+ */
+ bool canAppendWithoutRealloc(size_t aNeeded) const;
+
+ /** Potentially fallible append operations. */
+
+ /**
+ * This can take either a T& or a T&&. Given a T&&, it moves |aU| into the
+ * vector, instead of copying it. If it fails, |aU| is left unmoved. ("We are
+ * not amused.")
+ */
+ template <typename U>
+ [[nodiscard]] bool append(U&& aU);
+
+ /**
+ * Construct a T in-place as a new entry at the end of this vector.
+ */
+ template <typename... Args>
+ [[nodiscard]] bool emplaceBack(Args&&... aArgs) {
+ if (!growByUninitialized(1)) return false;
+ Impl::new_(&back(), std::forward<Args>(aArgs)...);
+ return true;
+ }
+
+ template <typename U, size_t O, class BP>
+ [[nodiscard]] bool appendAll(const Vector<U, O, BP>& aU);
+ template <typename U, size_t O, class BP>
+ [[nodiscard]] bool appendAll(Vector<U, O, BP>&& aU);
+ [[nodiscard]] bool appendN(const T& aT, size_t aN);
+ template <typename U>
+ [[nodiscard]] bool append(const U* aBegin, const U* aEnd);
+ template <typename U>
+ [[nodiscard]] bool append(const U* aBegin, size_t aLength);
+ template <typename U>
+ [[nodiscard]] bool moveAppend(U* aBegin, U* aEnd);
+
+ /*
+ * Guaranteed-infallible append operations for use upon vectors whose
+ * memory has been pre-reserved. Don't use this if you haven't reserved the
+ * memory!
+ */
+ template <typename U>
+ void infallibleAppend(U&& aU) {
+ internalAppend(std::forward<U>(aU));
+ }
+ void infallibleAppendN(const T& aT, size_t aN) { internalAppendN(aT, aN); }
+ template <typename U>
+ void infallibleAppend(const U* aBegin, const U* aEnd) {
+ internalAppend(aBegin, PointerRangeSize(aBegin, aEnd));
+ }
+ template <typename U>
+ void infallibleAppend(const U* aBegin, size_t aLength) {
+ internalAppend(aBegin, aLength);
+ }
+ template <typename... Args>
+ void infallibleEmplaceBack(Args&&... aArgs) {
+ infallibleGrowByUninitialized(1);
+ Impl::new_(&back(), std::forward<Args>(aArgs)...);
+ }
+
+ void popBack();
+
+ T popCopy();
+
+ /**
+ * If elements are stored in-place, return nullptr and leave this vector
+ * unmodified.
+ *
+ * Otherwise return this vector's elements buffer, and clear this vector as if
+ * by clearAndFree(). The caller now owns the buffer and is responsible for
+ * deallocating it consistent with this vector's AllocPolicy.
+ *
+ * N.B. Although a T*, only the range [0, length()) is constructed.
+ */
+ [[nodiscard]] T* extractRawBuffer();
+
+ /**
+ * If elements are stored in-place, allocate a new buffer, move this vector's
+ * elements into it, and return that buffer.
+ *
+ * Otherwise return this vector's elements buffer. The caller now owns the
+ * buffer and is responsible for deallocating it consistent with this vector's
+ * AllocPolicy.
+ *
+ * This vector is cleared, as if by clearAndFree(), when this method
+ * succeeds. This method fails and returns nullptr only if new elements buffer
+ * allocation fails.
+ *
+ * N.B. Only the range [0, length()) of the returned buffer is constructed.
+ * If any of these elements are uninitialized (as growByUninitialized
+ * enables), behavior is undefined.
+ */
+ [[nodiscard]] T* extractOrCopyRawBuffer();
+
+ /**
+ * Transfer ownership of an array of objects into the vector. The caller
+ * must have allocated the array in accordance with this vector's
+ * AllocPolicy.
+ *
+ * N.B. This call assumes that there are no uninitialized elements in the
+ * passed range [aP, aP + aLength). The range [aP + aLength, aP +
+ * aCapacity) must be allocated uninitialized memory.
+ */
+ void replaceRawBuffer(T* aP, size_t aLength, size_t aCapacity);
+
+ /**
+ * Transfer ownership of an array of objects into the vector. The caller
+ * must have allocated the array in accordance with this vector's
+ * AllocPolicy.
+ *
+ * N.B. This call assumes that there are no uninitialized elements in the
+ * passed array.
+ */
+ void replaceRawBuffer(T* aP, size_t aLength);
+
+ /**
+ * Places |aVal| at position |aP|, shifting existing elements from |aP| onward
+ * one position higher. On success, |aP| should not be reused because it'll
+ * be a dangling pointer if reallocation of the vector storage occurred; the
+ * return value should be used instead. On failure, nullptr is returned.
+ *
+ * Example usage:
+ *
+ * if (!(p = vec.insert(p, val))) {
+ * <handle failure>
+ * }
+ * <keep working with p>
+ *
+ * This is inherently a linear-time operation. Be careful!
+ */
+ template <typename U>
+ [[nodiscard]] T* insert(T* aP, U&& aVal);
+
+ /**
+ * Removes the element |aT|, which must fall in the bounds [begin, end),
+ * shifting existing elements from |aT + 1| onward one position lower.
+ */
+ void erase(T* aT);
+
+ /**
+ * Removes the elements [|aBegin|, |aEnd|), which must fall in the bounds
+ * [begin, end), shifting existing elements from |aEnd| onward to aBegin's old
+ * position.
+ */
+ void erase(T* aBegin, T* aEnd);
+
+ /**
+ * Removes all elements that satisfy the predicate, shifting existing elements
+ * lower to fill erased gaps.
+ */
+ template <typename Pred>
+ void eraseIf(Pred aPred);
+
+ /**
+ * Removes all elements that compare equal to |aU|, shifting existing elements
+ * lower to fill erased gaps.
+ */
+ template <typename U>
+ void eraseIfEqual(const U& aU);
+
+ /**
+ * Measure the size of the vector's heap-allocated storage.
+ */
+ size_t sizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const;
+
+ /**
+ * Like sizeOfExcludingThis, but also measures the size of the vector
+ * object (which must be heap-allocated) itself.
+ */
+ size_t sizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;
+
+ void swap(Vector& aOther);
+
+ private:
+ Vector(const Vector&) = delete;
+ void operator=(const Vector&) = delete;
+};
+
+/* This does the re-entrancy check plus several other sanity checks. */
+#define MOZ_REENTRANCY_GUARD_ET_AL \
+ ReentrancyGuard g(*this); \
+ MOZ_ASSERT_IF(usingInlineStorage(), mTail.mCapacity == kInlineCapacity); \
+ MOZ_ASSERT(reserved() <= mTail.mCapacity); \
+ MOZ_ASSERT(mLength <= reserved()); \
+ MOZ_ASSERT(mLength <= mTail.mCapacity)
+
+/* Vector Implementation */
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE Vector<T, N, AP>::Vector(AP aAP)
+ : AP(std::move(aAP)),
+ mLength(0),
+ mTail(kInlineCapacity, 0)
+#ifdef DEBUG
+ ,
+ mEntered(false)
+#endif
+{
+ mBegin = inlineStorage();
+}
+
+/* Move constructor. */
+template <typename T, size_t N, class AllocPolicy>
+MOZ_ALWAYS_INLINE Vector<T, N, AllocPolicy>::Vector(Vector&& aRhs)
+ : AllocPolicy(std::move(aRhs))
+#ifdef DEBUG
+ ,
+ mEntered(false)
+#endif
+{
+ mLength = aRhs.mLength;
+ mTail.mCapacity = aRhs.mTail.mCapacity;
+#ifdef DEBUG
+ mTail.mReserved = aRhs.mTail.mReserved;
+#endif
+
+ if (aRhs.usingInlineStorage()) {
+ /* We can't move the buffer over in this case, so copy elements. */
+ mBegin = inlineStorage();
+ Impl::moveConstruct(mBegin, aRhs.beginNoCheck(), aRhs.endNoCheck());
+ /*
+ * Leave aRhs's mLength, mBegin, mCapacity, and mReserved as they are.
+ * The elements in its in-line storage still need to be destroyed.
+ */
+ } else {
+ /*
+ * Take src's buffer, and turn src into an empty vector using
+ * in-line storage.
+ */
+ mBegin = aRhs.mBegin;
+ aRhs.mBegin = aRhs.inlineStorage();
+ aRhs.mTail.mCapacity = kInlineCapacity;
+ aRhs.mLength = 0;
+#ifdef DEBUG
+ aRhs.mTail.mReserved = 0;
+#endif
+ }
+}
+
+/* Move assignment. */
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE Vector<T, N, AP>& Vector<T, N, AP>::operator=(Vector&& aRhs) {
+ MOZ_ASSERT(this != &aRhs, "self-move assignment is prohibited");
+ this->~Vector();
+ new (KnownNotNull, this) Vector(std::move(aRhs));
+ return *this;
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE Vector<T, N, AP>::~Vector() {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ Impl::destroy(beginNoCheck(), endNoCheck());
+ if (!usingInlineStorage()) {
+ this->free_(beginNoCheck(), mTail.mCapacity);
+ }
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::reverse() {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ T* elems = mBegin;
+ size_t len = mLength;
+ size_t mid = len / 2;
+ for (size_t i = 0; i < mid; i++) {
+ std::swap(elems[i], elems[len - i - 1]);
+ }
+}
+
+/*
+ * This function will create a new heap buffer with capacity aNewCap,
+ * move all elements in the inline buffer to this new buffer,
+ * and fail on OOM.
+ */
+template <typename T, size_t N, class AP>
+inline bool Vector<T, N, AP>::convertToHeapStorage(size_t aNewCap) {
+ MOZ_ASSERT(usingInlineStorage());
+
+ /* Allocate buffer. */
+ MOZ_ASSERT(!detail::CapacityHasExcessSpace<sizeof(T)>(aNewCap));
+ T* newBuf = this->template pod_malloc<T>(aNewCap);
+ if (MOZ_UNLIKELY(!newBuf)) {
+ return false;
+ }
+
+ /* Copy inline elements into heap buffer. */
+ Impl::moveConstruct(newBuf, beginNoCheck(), endNoCheck());
+ Impl::destroy(beginNoCheck(), endNoCheck());
+
+ /* Switch in heap buffer. */
+ mBegin = newBuf;
+ /* mLength is unchanged. */
+ mTail.mCapacity = aNewCap;
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+MOZ_NEVER_INLINE bool Vector<T, N, AP>::growStorageBy(size_t aIncr) {
+ MOZ_ASSERT(mLength + aIncr > mTail.mCapacity);
+
+ size_t newCap;
+
+ if (aIncr == 1 && usingInlineStorage()) {
+ /* This case occurs in ~70--80% of the calls to this function. */
+ constexpr size_t newSize =
+ tl::RoundUpPow2<(kInlineCapacity + 1) * sizeof(T)>::value;
+ static_assert(newSize / sizeof(T) > 0,
+ "overflow when exceeding inline Vector storage");
+ newCap = newSize / sizeof(T);
+ } else {
+ newCap = detail::ComputeGrowth<AP, sizeof(T)>(mLength, aIncr, true);
+ if (MOZ_UNLIKELY(newCap == 0)) {
+ this->reportAllocOverflow();
+ return false;
+ }
+ }
+
+ if (usingInlineStorage()) {
+ return convertToHeapStorage(newCap);
+ }
+
+ return Impl::growTo(*this, newCap);
+}
+
+template <typename T, size_t N, class AP>
+inline bool Vector<T, N, AP>::initCapacity(size_t aRequest) {
+ MOZ_ASSERT(empty());
+ MOZ_ASSERT(usingInlineStorage());
+ if (aRequest == 0) {
+ return true;
+ }
+ T* newbuf = this->template pod_malloc<T>(aRequest);
+ if (MOZ_UNLIKELY(!newbuf)) {
+ return false;
+ }
+ mBegin = newbuf;
+ mTail.mCapacity = aRequest;
+#ifdef DEBUG
+ mTail.mReserved = aRequest;
+#endif
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+inline bool Vector<T, N, AP>::initLengthUninitialized(size_t aRequest) {
+ if (!initCapacity(aRequest)) {
+ return false;
+ }
+ infallibleGrowByUninitialized(aRequest);
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+inline bool Vector<T, N, AP>::maybeCheckSimulatedOOM(size_t aRequestedSize) {
+ if (aRequestedSize <= N) {
+ return true;
+ }
+
+#ifdef DEBUG
+ if (aRequestedSize <= mTail.mReserved) {
+ return true;
+ }
+#endif
+
+ return allocPolicy().checkSimulatedOOM();
+}
+
+template <typename T, size_t N, class AP>
+inline bool Vector<T, N, AP>::reserve(size_t aRequest) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ if (aRequest > mTail.mCapacity) {
+ if (MOZ_UNLIKELY(!growStorageBy(aRequest - mLength))) {
+ return false;
+ }
+ } else if (!maybeCheckSimulatedOOM(aRequest)) {
+ return false;
+ }
+#ifdef DEBUG
+ if (aRequest > mTail.mReserved) {
+ mTail.mReserved = aRequest;
+ }
+ MOZ_ASSERT(mLength <= mTail.mReserved);
+ MOZ_ASSERT(mTail.mReserved <= mTail.mCapacity);
+#endif
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+inline void Vector<T, N, AP>::shrinkBy(size_t aIncr) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ MOZ_ASSERT(aIncr <= mLength);
+ Impl::destroy(endNoCheck() - aIncr, endNoCheck());
+ mLength -= aIncr;
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::shrinkTo(size_t aNewLength) {
+ MOZ_ASSERT(aNewLength <= mLength);
+ shrinkBy(mLength - aNewLength);
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::growBy(size_t aIncr) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ if (aIncr > mTail.mCapacity - mLength) {
+ if (MOZ_UNLIKELY(!growStorageBy(aIncr))) {
+ return false;
+ }
+ } else if (!maybeCheckSimulatedOOM(mLength + aIncr)) {
+ return false;
+ }
+ MOZ_ASSERT(mLength + aIncr <= mTail.mCapacity);
+ T* newend = endNoCheck() + aIncr;
+ Impl::initialize(endNoCheck(), newend);
+ mLength += aIncr;
+#ifdef DEBUG
+ if (mLength > mTail.mReserved) {
+ mTail.mReserved = mLength;
+ }
+#endif
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::growByUninitialized(size_t aIncr) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ if (aIncr > mTail.mCapacity - mLength) {
+ if (MOZ_UNLIKELY(!growStorageBy(aIncr))) {
+ return false;
+ }
+ } else if (!maybeCheckSimulatedOOM(mLength + aIncr)) {
+ return false;
+ }
+#ifdef DEBUG
+ if (mLength + aIncr > mTail.mReserved) {
+ mTail.mReserved = mLength + aIncr;
+ }
+#endif
+ infallibleGrowByUninitialized(aIncr);
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::infallibleGrowByUninitialized(
+ size_t aIncr) {
+ MOZ_ASSERT(mLength + aIncr <= reserved());
+ mLength += aIncr;
+}
+
+template <typename T, size_t N, class AP>
+inline bool Vector<T, N, AP>::resize(size_t aNewLength) {
+ size_t curLength = mLength;
+ if (aNewLength > curLength) {
+ return growBy(aNewLength - curLength);
+ }
+ shrinkBy(curLength - aNewLength);
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::resizeUninitialized(
+ size_t aNewLength) {
+ size_t curLength = mLength;
+ if (aNewLength > curLength) {
+ return growByUninitialized(aNewLength - curLength);
+ }
+ shrinkBy(curLength - aNewLength);
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+inline void Vector<T, N, AP>::clear() {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ Impl::destroy(beginNoCheck(), endNoCheck());
+ mLength = 0;
+}
+
+template <typename T, size_t N, class AP>
+inline void Vector<T, N, AP>::clearAndFree() {
+ clear();
+
+ if (usingInlineStorage()) {
+ return;
+ }
+ this->free_(beginNoCheck(), mTail.mCapacity);
+ mBegin = inlineStorage();
+ mTail.mCapacity = kInlineCapacity;
+#ifdef DEBUG
+ mTail.mReserved = 0;
+#endif
+}
+
+template <typename T, size_t N, class AP>
+inline bool Vector<T, N, AP>::shrinkStorageToFit() {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+
+ const auto length = this->length();
+ if (usingInlineStorage() || length == capacity()) {
+ return true;
+ }
+
+ if (!length) {
+ this->free_(beginNoCheck(), mTail.mCapacity);
+ mBegin = inlineStorage();
+ mTail.mCapacity = kInlineCapacity;
+#ifdef DEBUG
+ mTail.mReserved = 0;
+#endif
+ return true;
+ }
+
+ T* newBuf;
+ size_t newCap;
+ if (length <= kInlineCapacity) {
+ newBuf = inlineStorage();
+ newCap = kInlineCapacity;
+ } else {
+ if (kElemIsPod) {
+ newBuf = this->template pod_realloc<T>(beginNoCheck(), mTail.mCapacity,
+ length);
+ } else {
+ newBuf = this->template pod_malloc<T>(length);
+ }
+ if (MOZ_UNLIKELY(!newBuf)) {
+ return false;
+ }
+ newCap = length;
+ }
+ if (!kElemIsPod || newBuf == inlineStorage()) {
+ Impl::moveConstruct(newBuf, beginNoCheck(), endNoCheck());
+ Impl::destroy(beginNoCheck(), endNoCheck());
+ }
+ if (!kElemIsPod) {
+ this->free_(beginNoCheck(), mTail.mCapacity);
+ }
+ mBegin = newBuf;
+ mTail.mCapacity = newCap;
+#ifdef DEBUG
+ mTail.mReserved = length;
+#endif
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+inline bool Vector<T, N, AP>::canAppendWithoutRealloc(size_t aNeeded) const {
+ return mLength + aNeeded <= mTail.mCapacity;
+}
+
+template <typename T, size_t N, class AP>
+template <typename U, size_t O, class BP>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::internalAppendAll(
+ const Vector<U, O, BP>& aOther) {
+ internalAppend(aOther.begin(), aOther.length());
+}
+
+template <typename T, size_t N, class AP>
+template <typename U>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::internalAppend(U&& aU) {
+ MOZ_ASSERT(mLength + 1 <= mTail.mReserved);
+ MOZ_ASSERT(mTail.mReserved <= mTail.mCapacity);
+ Impl::new_(endNoCheck(), std::forward<U>(aU));
+ ++mLength;
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::appendN(const T& aT, size_t aNeeded) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ if (mLength + aNeeded > mTail.mCapacity) {
+ if (MOZ_UNLIKELY(!growStorageBy(aNeeded))) {
+ return false;
+ }
+ } else if (!maybeCheckSimulatedOOM(mLength + aNeeded)) {
+ return false;
+ }
+#ifdef DEBUG
+ if (mLength + aNeeded > mTail.mReserved) {
+ mTail.mReserved = mLength + aNeeded;
+ }
+#endif
+ internalAppendN(aT, aNeeded);
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::internalAppendN(const T& aT,
+ size_t aNeeded) {
+ MOZ_ASSERT(mLength + aNeeded <= mTail.mReserved);
+ MOZ_ASSERT(mTail.mReserved <= mTail.mCapacity);
+ Impl::copyConstructN(endNoCheck(), aNeeded, aT);
+ mLength += aNeeded;
+}
+
+template <typename T, size_t N, class AP>
+template <typename U>
+inline T* Vector<T, N, AP>::insert(T* aP, U&& aVal) {
+ MOZ_ASSERT(begin() <= aP);
+ MOZ_ASSERT(aP <= end());
+ size_t pos = aP - begin();
+ MOZ_ASSERT(pos <= mLength);
+ size_t oldLength = mLength;
+ if (pos == oldLength) {
+ if (!append(std::forward<U>(aVal))) {
+ return nullptr;
+ }
+ } else {
+ T oldBack = std::move(back());
+ if (!append(std::move(oldBack))) {
+ return nullptr;
+ }
+ for (size_t i = oldLength - 1; i > pos; --i) {
+ (*this)[i] = std::move((*this)[i - 1]);
+ }
+ (*this)[pos] = std::forward<U>(aVal);
+ }
+ return begin() + pos;
+}
+
+template <typename T, size_t N, class AP>
+inline void Vector<T, N, AP>::erase(T* aIt) {
+ MOZ_ASSERT(begin() <= aIt);
+ MOZ_ASSERT(aIt < end());
+ while (aIt + 1 < end()) {
+ *aIt = std::move(*(aIt + 1));
+ ++aIt;
+ }
+ popBack();
+}
+
+template <typename T, size_t N, class AP>
+inline void Vector<T, N, AP>::erase(T* aBegin, T* aEnd) {
+ MOZ_ASSERT(begin() <= aBegin);
+ MOZ_ASSERT(aBegin <= aEnd);
+ MOZ_ASSERT(aEnd <= end());
+ while (aEnd < end()) {
+ *aBegin++ = std::move(*aEnd++);
+ }
+ shrinkBy(aEnd - aBegin);
+}
+
+template <typename T, size_t N, class AP>
+template <typename Pred>
+void Vector<T, N, AP>::eraseIf(Pred aPred) {
+ // remove_if finds the first element to be erased, and then efficiently move-
+ // assigns elements to effectively overwrite elements that satisfy the
+ // predicate. It returns the new end pointer, after which there are only
+ // moved-from elements ready to be destroyed, so we just need to shrink the
+ // vector accordingly.
+ T* newEnd = std::remove_if(begin(), end(),
+ [&aPred](const T& aT) { return aPred(aT); });
+ MOZ_ASSERT(newEnd <= end());
+ shrinkBy(end() - newEnd);
+}
+
+template <typename T, size_t N, class AP>
+template <typename U>
+void Vector<T, N, AP>::eraseIfEqual(const U& aU) {
+ return eraseIf([&aU](const T& aT) { return aT == aU; });
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::internalEnsureCapacity(
+ size_t aNeeded) {
+ if (mLength + aNeeded > mTail.mCapacity) {
+ if (MOZ_UNLIKELY(!growStorageBy(aNeeded))) {
+ return false;
+ }
+ } else if (!maybeCheckSimulatedOOM(mLength + aNeeded)) {
+ return false;
+ }
+#ifdef DEBUG
+ if (mLength + aNeeded > mTail.mReserved) {
+ mTail.mReserved = mLength + aNeeded;
+ }
+#endif
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+template <typename U>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::append(const U* aInsBegin,
+ const U* aInsEnd) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ const size_t needed = PointerRangeSize(aInsBegin, aInsEnd);
+ if (!internalEnsureCapacity(needed)) {
+ return false;
+ }
+ internalAppend(aInsBegin, needed);
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+template <typename U>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::internalAppend(const U* aInsBegin,
+ size_t aInsLength) {
+ MOZ_ASSERT(mLength + aInsLength <= mTail.mReserved);
+ MOZ_ASSERT(mTail.mReserved <= mTail.mCapacity);
+ Impl::copyConstruct(endNoCheck(), aInsBegin, aInsBegin + aInsLength);
+ mLength += aInsLength;
+}
+
+template <typename T, size_t N, class AP>
+template <typename U>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::moveAppend(U* aInsBegin, U* aInsEnd) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ const size_t needed = PointerRangeSize(aInsBegin, aInsEnd);
+ if (!internalEnsureCapacity(needed)) {
+ return false;
+ }
+ internalMoveAppend(aInsBegin, needed);
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+template <typename U>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::internalMoveAppend(U* aInsBegin,
+ size_t aInsLength) {
+ MOZ_ASSERT(mLength + aInsLength <= mTail.mReserved);
+ MOZ_ASSERT(mTail.mReserved <= mTail.mCapacity);
+ Impl::moveConstruct(endNoCheck(), aInsBegin, aInsBegin + aInsLength);
+ mLength += aInsLength;
+}
+
+template <typename T, size_t N, class AP>
+template <typename U>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::append(U&& aU) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ if (mLength == mTail.mCapacity) {
+ if (MOZ_UNLIKELY(!growStorageBy(1))) {
+ return false;
+ }
+ } else if (!maybeCheckSimulatedOOM(mLength + 1)) {
+ return false;
+ }
+#ifdef DEBUG
+ if (mLength + 1 > mTail.mReserved) {
+ mTail.mReserved = mLength + 1;
+ }
+#endif
+ internalAppend(std::forward<U>(aU));
+ return true;
+}
+
+template <typename T, size_t N, class AP>
+template <typename U, size_t O, class BP>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::appendAll(
+ const Vector<U, O, BP>& aOther) {
+ return append(aOther.begin(), aOther.length());
+}
+
+template <typename T, size_t N, class AP>
+template <typename U, size_t O, class BP>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::appendAll(Vector<U, O, BP>&& aOther) {
+ if (empty() && capacity() < aOther.length()) {
+ *this = std::move(aOther);
+ return true;
+ }
+
+ if (moveAppend(aOther.begin(), aOther.end())) {
+ aOther.clearAndFree();
+ return true;
+ }
+
+ return false;
+}
+
+template <typename T, size_t N, class AP>
+template <class U>
+MOZ_ALWAYS_INLINE bool Vector<T, N, AP>::append(const U* aInsBegin,
+ size_t aInsLength) {
+ return append(aInsBegin, aInsBegin + aInsLength);
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE void Vector<T, N, AP>::popBack() {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+ MOZ_ASSERT(!empty());
+ --mLength;
+ endNoCheck()->~T();
+}
+
+template <typename T, size_t N, class AP>
+MOZ_ALWAYS_INLINE T Vector<T, N, AP>::popCopy() {
+ T ret = back();
+ popBack();
+ return ret;
+}
+
+template <typename T, size_t N, class AP>
+inline T* Vector<T, N, AP>::extractRawBuffer() {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+
+ if (usingInlineStorage()) {
+ return nullptr;
+ }
+
+ T* ret = mBegin;
+ mBegin = inlineStorage();
+ mLength = 0;
+ mTail.mCapacity = kInlineCapacity;
+#ifdef DEBUG
+ mTail.mReserved = 0;
+#endif
+ return ret;
+}
+
+template <typename T, size_t N, class AP>
+inline T* Vector<T, N, AP>::extractOrCopyRawBuffer() {
+ if (T* ret = extractRawBuffer()) {
+ return ret;
+ }
+
+ MOZ_REENTRANCY_GUARD_ET_AL;
+
+ T* copy = this->template pod_malloc<T>(mLength);
+ if (!copy) {
+ return nullptr;
+ }
+
+ Impl::moveConstruct(copy, beginNoCheck(), endNoCheck());
+ Impl::destroy(beginNoCheck(), endNoCheck());
+ mBegin = inlineStorage();
+ mLength = 0;
+ mTail.mCapacity = kInlineCapacity;
+#ifdef DEBUG
+ mTail.mReserved = 0;
+#endif
+ return copy;
+}
+
+template <typename T, size_t N, class AP>
+inline void Vector<T, N, AP>::replaceRawBuffer(T* aP, size_t aLength,
+ size_t aCapacity) {
+ MOZ_REENTRANCY_GUARD_ET_AL;
+
+ /* Destroy what we have. */
+ Impl::destroy(beginNoCheck(), endNoCheck());
+ if (!usingInlineStorage()) {
+ this->free_(beginNoCheck(), mTail.mCapacity);
+ }
+
+ /* Take in the new buffer. */
+ if (aCapacity <= kInlineCapacity) {
+ /*
+ * We convert to inline storage if possible, even though aP might
+ * otherwise be acceptable. Maybe this behaviour should be
+ * specifiable with an argument to this function.
+ */
+ mBegin = inlineStorage();
+ mLength = aLength;
+ mTail.mCapacity = kInlineCapacity;
+ Impl::moveConstruct(mBegin, aP, aP + aLength);
+ Impl::destroy(aP, aP + aLength);
+ this->free_(aP, aCapacity);
+ } else {
+ mBegin = aP;
+ mLength = aLength;
+ mTail.mCapacity = aCapacity;
+ }
+#ifdef DEBUG
+ mTail.mReserved = aCapacity;
+#endif
+}
+
+template <typename T, size_t N, class AP>
+inline void Vector<T, N, AP>::replaceRawBuffer(T* aP, size_t aLength) {
+ replaceRawBuffer(aP, aLength, aLength);
+}
+
+template <typename T, size_t N, class AP>
+inline size_t Vector<T, N, AP>::sizeOfExcludingThis(
+ MallocSizeOf aMallocSizeOf) const {
+ return usingInlineStorage() ? 0 : aMallocSizeOf(beginNoCheck());
+}
+
+template <typename T, size_t N, class AP>
+inline size_t Vector<T, N, AP>::sizeOfIncludingThis(
+ MallocSizeOf aMallocSizeOf) const {
+ return aMallocSizeOf(this) + sizeOfExcludingThis(aMallocSizeOf);
+}
+
+template <typename T, size_t N, class AP>
+inline void Vector<T, N, AP>::swap(Vector& aOther) {
+ static_assert(N == 0, "still need to implement this for N != 0");
+
+ // This only works when inline storage is always empty.
+ if (!usingInlineStorage() && aOther.usingInlineStorage()) {
+ aOther.mBegin = mBegin;
+ mBegin = inlineStorage();
+ } else if (usingInlineStorage() && !aOther.usingInlineStorage()) {
+ mBegin = aOther.mBegin;
+ aOther.mBegin = aOther.inlineStorage();
+ } else if (!usingInlineStorage() && !aOther.usingInlineStorage()) {
+ std::swap(mBegin, aOther.mBegin);
+ } else {
+ // This case is a no-op, since we'd set both to use their inline storage.
+ }
+
+ std::swap(mLength, aOther.mLength);
+ std::swap(mTail.mCapacity, aOther.mTail.mCapacity);
+#ifdef DEBUG
+ std::swap(mTail.mReserved, aOther.mTail.mReserved);
+#endif
+}
+
+} // namespace mozilla
+
+#endif /* mozilla_Vector_h */