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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /js/public/GCVector.h
parentInitial commit. (diff)
downloadfirefox-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>
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-rw-r--r--js/public/GCVector.h366
1 files changed, 366 insertions, 0 deletions
diff --git a/js/public/GCVector.h b/js/public/GCVector.h
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+/* -*- 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/. */
+
+#ifndef js_GCVector_h
+#define js_GCVector_h
+
+#include "mozilla/Assertions.h" // MOZ_ASSERT
+#include "mozilla/Attributes.h" // MOZ_STACK_CLASS
+#include "mozilla/MemoryReporting.h" // MallocSizeOf
+#include "mozilla/Span.h"
+#include "mozilla/Vector.h"
+
+#include <stddef.h> // size_t
+#include <utility> // forward, move
+
+#include "js/AllocPolicy.h"
+#include "js/GCPolicyAPI.h"
+#include "js/RootingAPI.h"
+
+class JSTracer;
+struct JSContext;
+
+namespace JS {
+
+// A GCVector is a Vector with an additional trace method that knows how
+// to visit all of the items stored in the Vector. For vectors that contain GC
+// things, this is usually more convenient than manually iterating and marking
+// the contents.
+//
+// Most types of GC pointers as keys and values can be traced with no extra
+// infrastructure. For structs and non-gc-pointer members, ensure that there is
+// a specialization of GCPolicy<T> with an appropriate trace method available
+// to handle the custom type. Generic helpers can be found in
+// js/public/TracingAPI.h.
+//
+// Note that although this Vector's trace will deal correctly with moved items,
+// it does not itself know when to barrier or trace items. To function properly
+// it must either be used with Rooted, or barriered and traced manually.
+template <typename T, size_t MinInlineCapacity = 0,
+ typename AllocPolicy = js::TempAllocPolicy>
+class GCVector {
+ mozilla::Vector<T, MinInlineCapacity, AllocPolicy> vector;
+
+ public:
+ using ElementType = T;
+
+ explicit GCVector(AllocPolicy alloc) : vector(std::move(alloc)) {}
+ GCVector() : GCVector(AllocPolicy()) {}
+
+ GCVector(GCVector&& vec) : vector(std::move(vec.vector)) {}
+
+ GCVector& operator=(GCVector&& vec) {
+ vector = std::move(vec.vector);
+ return *this;
+ }
+
+ size_t length() const { return vector.length(); }
+ bool empty() const { return vector.empty(); }
+ size_t capacity() const { return vector.capacity(); }
+
+ T* begin() { return vector.begin(); }
+ const T* begin() const { return vector.begin(); }
+
+ T* end() { return vector.end(); }
+ const T* end() const { return vector.end(); }
+
+ T& operator[](size_t i) { return vector[i]; }
+ const T& operator[](size_t i) const { return vector[i]; }
+
+ T& back() { return vector.back(); }
+ const T& back() const { return vector.back(); }
+
+ operator mozilla::Span<T>() { return vector; }
+ operator mozilla::Span<const T>() const { return vector; }
+
+ bool initCapacity(size_t cap) { return vector.initCapacity(cap); }
+ [[nodiscard]] bool reserve(size_t req) { return vector.reserve(req); }
+ void shrinkBy(size_t amount) { return vector.shrinkBy(amount); }
+ void shrinkTo(size_t newLen) { return vector.shrinkTo(newLen); }
+ [[nodiscard]] bool growBy(size_t amount) { return vector.growBy(amount); }
+ [[nodiscard]] bool resize(size_t newLen) { return vector.resize(newLen); }
+
+ void clear() { return vector.clear(); }
+ void clearAndFree() { return vector.clearAndFree(); }
+
+ template <typename U>
+ bool append(U&& item) {
+ return vector.append(std::forward<U>(item));
+ }
+
+ void erase(T* it) { vector.erase(it); }
+ void erase(T* begin, T* end) { vector.erase(begin, end); }
+ template <typename Pred>
+ void eraseIf(Pred pred) {
+ vector.eraseIf(pred);
+ }
+ template <typename U>
+ void eraseIfEqual(const U& u) {
+ vector.eraseIfEqual(u);
+ }
+
+ template <typename... Args>
+ [[nodiscard]] bool emplaceBack(Args&&... args) {
+ return vector.emplaceBack(std::forward<Args>(args)...);
+ }
+
+ template <typename... Args>
+ void infallibleEmplaceBack(Args&&... args) {
+ vector.infallibleEmplaceBack(std::forward<Args>(args)...);
+ }
+
+ template <typename U>
+ void infallibleAppend(U&& aU) {
+ return vector.infallibleAppend(std::forward<U>(aU));
+ }
+ void infallibleAppendN(const T& aT, size_t aN) {
+ return vector.infallibleAppendN(aT, aN);
+ }
+ template <typename U>
+ void infallibleAppend(const U* aBegin, const U* aEnd) {
+ return vector.infallibleAppend(aBegin, aEnd);
+ }
+ template <typename U>
+ void infallibleAppend(const U* aBegin, size_t aLength) {
+ return vector.infallibleAppend(aBegin, aLength);
+ }
+
+ template <typename U>
+ [[nodiscard]] bool appendAll(const U& aU) {
+ return vector.append(aU.begin(), aU.end());
+ }
+ template <typename T2, size_t MinInlineCapacity2, typename AllocPolicy2>
+ [[nodiscard]] bool appendAll(
+ GCVector<T2, MinInlineCapacity2, AllocPolicy2>&& aU) {
+ return vector.appendAll(aU.begin(), aU.end());
+ }
+
+ [[nodiscard]] bool appendN(const T& val, size_t count) {
+ return vector.appendN(val, count);
+ }
+
+ template <typename U>
+ [[nodiscard]] bool append(const U* aBegin, const U* aEnd) {
+ return vector.append(aBegin, aEnd);
+ }
+ template <typename U>
+ [[nodiscard]] bool append(const U* aBegin, size_t aLength) {
+ return vector.append(aBegin, aLength);
+ }
+
+ void popBack() { return vector.popBack(); }
+ T popCopy() { return vector.popCopy(); }
+
+ size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
+ return vector.sizeOfExcludingThis(mallocSizeOf);
+ }
+
+ size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
+ return vector.sizeOfIncludingThis(mallocSizeOf);
+ }
+
+ void trace(JSTracer* trc) {
+ for (auto& elem : vector) {
+ GCPolicy<T>::trace(trc, &elem, "vector element");
+ }
+ }
+
+ bool traceWeak(JSTracer* trc) {
+ mutableEraseIf(
+ [trc](T& elem) { return !GCPolicy<T>::traceWeak(trc, &elem); });
+ return !empty();
+ }
+
+ // Like eraseIf, but may mutate the contents of the vector. Iterates from
+ // |startIndex| to the last element of the vector.
+ template <typename Pred>
+ void mutableEraseIf(Pred pred, size_t startIndex = 0) {
+ MOZ_ASSERT(startIndex <= length());
+
+ T* src = begin() + startIndex;
+ T* dst = src;
+ while (src != end()) {
+ if (!pred(*src)) {
+ if (src != dst) {
+ *dst = std::move(*src);
+ }
+ dst++;
+ }
+ src++;
+ }
+
+ MOZ_ASSERT(dst <= end());
+ shrinkBy(end() - dst);
+ }
+};
+
+// AllocPolicy is optional. It has a default value declared in TypeDecls.h
+template <typename T, typename AllocPolicy>
+class MOZ_STACK_CLASS StackGCVector : public GCVector<T, 8, AllocPolicy> {
+ public:
+ using Base = GCVector<T, 8, AllocPolicy>;
+
+ private:
+ // Inherit constructor from GCVector.
+ using Base::Base;
+};
+
+} // namespace JS
+
+namespace js {
+
+template <typename Wrapper, typename T, size_t Capacity, typename AllocPolicy>
+class WrappedPtrOperations<JS::GCVector<T, Capacity, AllocPolicy>, Wrapper> {
+ using Vec = JS::GCVector<T, Capacity, AllocPolicy>;
+ const Vec& vec() const { return static_cast<const Wrapper*>(this)->get(); }
+
+ public:
+ const AllocPolicy& allocPolicy() const { return vec().allocPolicy(); }
+ size_t length() const { return vec().length(); }
+ bool empty() const { return vec().empty(); }
+ size_t capacity() const { return vec().capacity(); }
+ const T* begin() const { return vec().begin(); }
+ const T* end() const { return vec().end(); }
+ const T& back() const { return vec().back(); }
+
+ JS::Handle<T> operator[](size_t aIndex) const {
+ return JS::Handle<T>::fromMarkedLocation(&vec().operator[](aIndex));
+ }
+};
+
+template <typename Wrapper, typename T, size_t Capacity, typename AllocPolicy>
+class MutableWrappedPtrOperations<JS::GCVector<T, Capacity, AllocPolicy>,
+ Wrapper>
+ : public WrappedPtrOperations<JS::GCVector<T, Capacity, AllocPolicy>,
+ Wrapper> {
+ using Vec = JS::GCVector<T, Capacity, AllocPolicy>;
+ const Vec& vec() const { return static_cast<const Wrapper*>(this)->get(); }
+ Vec& vec() { return static_cast<Wrapper*>(this)->get(); }
+
+ public:
+ const AllocPolicy& allocPolicy() const { return vec().allocPolicy(); }
+ AllocPolicy& allocPolicy() { return vec().allocPolicy(); }
+ const T* begin() const { return vec().begin(); }
+ T* begin() { return vec().begin(); }
+ const T* end() const { return vec().end(); }
+ T* end() { return vec().end(); }
+ const T& back() const { return vec().back(); }
+ T& back() { return vec().back(); }
+
+ JS::Handle<T> operator[](size_t aIndex) const {
+ return JS::Handle<T>::fromMarkedLocation(&vec().operator[](aIndex));
+ }
+ JS::MutableHandle<T> operator[](size_t aIndex) {
+ return JS::MutableHandle<T>::fromMarkedLocation(&vec().operator[](aIndex));
+ }
+
+ [[nodiscard]] bool initCapacity(size_t aRequest) {
+ return vec().initCapacity(aRequest);
+ }
+ [[nodiscard]] bool reserve(size_t aRequest) {
+ return vec().reserve(aRequest);
+ }
+ void shrinkBy(size_t aIncr) { vec().shrinkBy(aIncr); }
+ [[nodiscard]] bool growBy(size_t aIncr) { return vec().growBy(aIncr); }
+ [[nodiscard]] bool resize(size_t aNewLength) {
+ return vec().resize(aNewLength);
+ }
+ void clear() { vec().clear(); }
+ void clearAndFree() { vec().clearAndFree(); }
+ template <typename U>
+ [[nodiscard]] bool append(U&& aU) {
+ return vec().append(std::forward<U>(aU));
+ }
+ template <typename... Args>
+ [[nodiscard]] bool emplaceBack(Args&&... aArgs) {
+ return vec().emplaceBack(std::forward<Args>(aArgs)...);
+ }
+ template <typename... Args>
+ void infallibleEmplaceBack(Args&&... args) {
+ vec().infallibleEmplaceBack(std::forward<Args>(args)...);
+ }
+ template <typename U>
+ [[nodiscard]] bool appendAll(U&& aU) {
+ return vec().appendAll(aU);
+ }
+ [[nodiscard]] bool appendN(const T& aT, size_t aN) {
+ return vec().appendN(aT, aN);
+ }
+ template <typename U>
+ [[nodiscard]] bool append(const U* aBegin, const U* aEnd) {
+ return vec().append(aBegin, aEnd);
+ }
+ template <typename U>
+ [[nodiscard]] bool append(const U* aBegin, size_t aLength) {
+ return vec().append(aBegin, aLength);
+ }
+ template <typename U>
+ void infallibleAppend(U&& aU) {
+ vec().infallibleAppend(std::forward<U>(aU));
+ }
+ void infallibleAppendN(const T& aT, size_t aN) {
+ vec().infallibleAppendN(aT, aN);
+ }
+ template <typename U>
+ void infallibleAppend(const U* aBegin, const U* aEnd) {
+ vec().infallibleAppend(aBegin, aEnd);
+ }
+ template <typename U>
+ void infallibleAppend(const U* aBegin, size_t aLength) {
+ vec().infallibleAppend(aBegin, aLength);
+ }
+ void popBack() { vec().popBack(); }
+ T popCopy() { return vec().popCopy(); }
+ void erase(T* aT) { vec().erase(aT); }
+ void erase(T* aBegin, T* aEnd) { vec().erase(aBegin, aEnd); }
+ template <typename Pred>
+ void eraseIf(Pred pred) {
+ vec().eraseIf(pred);
+ }
+ template <typename U>
+ void eraseIfEqual(const U& u) {
+ vec().eraseIfEqual(u);
+ }
+};
+
+template <typename Wrapper, typename T, typename AllocPolicy>
+class WrappedPtrOperations<JS::StackGCVector<T, AllocPolicy>, Wrapper>
+ : public WrappedPtrOperations<
+ typename JS::StackGCVector<T, AllocPolicy>::Base, Wrapper> {};
+
+template <typename Wrapper, typename T, typename AllocPolicy>
+class MutableWrappedPtrOperations<JS::StackGCVector<T, AllocPolicy>, Wrapper>
+ : public MutableWrappedPtrOperations<
+ typename JS::StackGCVector<T, AllocPolicy>::Base, Wrapper> {};
+
+} // namespace js
+
+namespace JS {
+
+// An automatically rooted GCVector for stack use.
+template <typename T>
+class RootedVector : public Rooted<StackGCVector<T>> {
+ using Vec = StackGCVector<T>;
+ using Base = Rooted<Vec>;
+
+ public:
+ explicit RootedVector(JSContext* cx) : Base(cx, Vec(cx)) {}
+};
+
+// For use in rust code, an analog to RootedVector that doesn't require
+// instances to be destroyed in LIFO order.
+template <typename T>
+class PersistentRootedVector : public PersistentRooted<StackGCVector<T>> {
+ using Vec = StackGCVector<T>;
+ using Base = PersistentRooted<Vec>;
+
+ public:
+ explicit PersistentRootedVector(JSContext* cx) : Base(cx, Vec(cx)) {}
+};
+
+} // namespace JS
+
+#endif // js_GCVector_h