summaryrefslogtreecommitdiffstats
path: root/js/src/irregexp/util/ZoneShim.h
diff options
context:
space:
mode:
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/src/irregexp/util/ZoneShim.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>
Diffstat (limited to 'js/src/irregexp/util/ZoneShim.h')
-rw-r--r--js/src/irregexp/util/ZoneShim.h417
1 files changed, 417 insertions, 0 deletions
diff --git a/js/src/irregexp/util/ZoneShim.h b/js/src/irregexp/util/ZoneShim.h
new file mode 100644
index 0000000000..f5dd33b8aa
--- /dev/null
+++ b/js/src/irregexp/util/ZoneShim.h
@@ -0,0 +1,417 @@
+// Copyright 2019 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_UTIL_ZONE_H_
+#define V8_UTIL_ZONE_H_
+
+#include <list>
+#include <map>
+#include <set>
+#include <unordered_map>
+#include <vector>
+
+#include "ds/LifoAlloc.h"
+#include "ds/Sort.h"
+#include "irregexp/util/VectorShim.h"
+
+namespace v8 {
+namespace internal {
+
+// V8::Zone ~= LifoAlloc
+class Zone {
+ public:
+ Zone(js::LifoAlloc& alloc) : lifoAlloc_(alloc) {}
+
+ template <typename T, typename... Args>
+ T* New(Args&&... args) {
+ js::LifoAlloc::AutoFallibleScope fallible(&lifoAlloc_);
+ js::AutoEnterOOMUnsafeRegion oomUnsafe;
+ void* memory = lifoAlloc_.alloc(sizeof(T));
+ if (!memory) {
+ oomUnsafe.crash("Irregexp Zone::New");
+ }
+ return new (memory) T(std::forward<Args>(args)...);
+ }
+
+ // Allocates uninitialized memory for 'length' number of T instances.
+ template <typename T>
+ T* NewArray(size_t length) {
+ js::LifoAlloc::AutoFallibleScope fallible(&lifoAlloc_);
+ js::AutoEnterOOMUnsafeRegion oomUnsafe;
+ void* memory = lifoAlloc_.alloc(length * sizeof(T));
+ if (!memory) {
+ oomUnsafe.crash("Irregexp Zone::New");
+ }
+ return static_cast<T*>(memory);
+ }
+
+ void DeleteAll() { lifoAlloc_.freeAll(); }
+
+ // Returns true if the total memory allocated exceeds a threshold.
+ static const size_t kExcessLimit = 256 * 1024 * 1024;
+ bool excess_allocation() const {
+ return lifoAlloc_.computedSizeOfExcludingThis() > kExcessLimit;
+ }
+
+ js::LifoAlloc& inner() { return lifoAlloc_; }
+
+ private:
+ js::LifoAlloc& lifoAlloc_;
+};
+
+// Superclass for classes allocated in a Zone.
+// Based on: https://github.com/v8/v8/blob/master/src/zone/zone.h
+class ZoneObject {
+ public:
+ // new (zone) SomeObject(...) was the old pattern.
+ // Delete the constructor to avoid using it accidentally.
+ void* operator new(size_t size, Zone* zone) = delete;
+
+ // Allow non-allocating placement new
+ void* operator new(size_t size, void* ptr) { return ptr; }
+
+ // Ideally, the delete operator should be private instead of
+ // public, but unfortunately the compiler sometimes synthesizes
+ // (unused) destructors for classes derived from ZoneObject, which
+ // require the operator to be visible. MSVC requires the delete
+ // operator to be public.
+
+ // ZoneObjects should never be deleted individually; use
+ // Zone::DeleteAll() to delete all zone objects in one go.
+ void operator delete(void*, size_t) { MOZ_CRASH("unreachable"); }
+ void operator delete(void* pointer, Zone* zone) { MOZ_CRASH("unreachable"); }
+};
+
+// ZoneLists are growable lists with constant-time access to the
+// elements. The list itself and all its elements are allocated in the
+// Zone. ZoneLists cannot be deleted individually; you can delete all
+// objects in the Zone by calling Zone::DeleteAll().
+// Used throughout irregexp.
+// Based on: https://github.com/v8/v8/blob/master/src/zone/zone-list.h
+template <typename T>
+class ZoneList final : public ZoneObject {
+ public:
+ // Construct a new ZoneList with the given capacity; the length is
+ // always zero. The capacity must be non-negative.
+ ZoneList(int capacity, Zone* zone) : capacity_(capacity) {
+ data_ = (capacity_ > 0) ? zone->NewArray<T>(capacity_) : nullptr;
+ }
+ // Construct a new ZoneList by copying the elements of the given ZoneList.
+ ZoneList(const ZoneList<T>& other, Zone* zone)
+ : ZoneList(other.length(), zone) {
+ AddAll(other, zone);
+ }
+
+ // Construct a new ZoneList by copying the elements of the given vector.
+ ZoneList(const base::Vector<const T>& other, Zone* zone)
+ : ZoneList(other.length(), zone) {
+ AddAll(other, zone);
+ }
+
+ ZoneList(ZoneList<T>&& other) { *this = std::move(other); }
+
+ ZoneList& operator=(ZoneList&& other) {
+ MOZ_ASSERT(!data_);
+ data_ = other.data_;
+ capacity_ = other.capacity_;
+ length_ = other.length_;
+ other.Clear();
+ return *this;
+ }
+
+ // Returns a reference to the element at index i. This reference is not safe
+ // to use after operations that can change the list's backing store
+ // (e.g. Add).
+ inline T& operator[](int i) const {
+ MOZ_ASSERT(i >= 0);
+ MOZ_ASSERT(static_cast<unsigned>(i) < static_cast<unsigned>(length_));
+ return data_[i];
+ }
+ inline T& at(int i) const { return operator[](i); }
+ inline T& last() const { return at(length_ - 1); }
+ inline T& first() const { return at(0); }
+
+ using iterator = T*;
+ inline iterator begin() const { return &data_[0]; }
+ inline iterator end() const { return &data_[length_]; }
+
+ inline bool is_empty() const { return length_ == 0; }
+ inline int length() const { return length_; }
+ inline int capacity() const { return capacity_; }
+
+ base::Vector<T> ToVector() const { return base::Vector<T>(data_, length_); }
+ base::Vector<T> ToVector(int start, int length) const {
+ return base::Vector<T>(data_ + start, std::min(length_ - start, length));
+ }
+
+ base::Vector<const T> ToConstVector() const {
+ return base::Vector<const T>(data_, length_);
+ }
+
+ // Adds a copy of the given 'element' to the end of the list,
+ // expanding the list if necessary.
+ void Add(const T& element, Zone* zone) {
+ if (length_ < capacity_) {
+ data_[length_++] = element;
+ } else {
+ ZoneList<T>::ResizeAdd(element, zone);
+ }
+ }
+ // Add all the elements from the argument list to this list.
+ void AddAll(const ZoneList<T>& other, Zone* zone) {
+ AddAll(other.ToVector(), zone);
+ }
+ // Add all the elements from the vector to this list.
+ void AddAll(const base::Vector<const T>& other, Zone* zone) {
+ int result_length = length_ + other.length();
+ if (capacity_ < result_length) {
+ Resize(result_length, zone);
+ }
+ if (std::is_fundamental<T>()) {
+ memcpy(data_ + length_, other.begin(), sizeof(*data_) * other.length());
+ } else {
+ for (int i = 0; i < other.length(); i++) {
+ data_[length_ + i] = other.at(i);
+ }
+ }
+ length_ = result_length;
+ }
+
+ // Overwrites the element at the specific index.
+ void Set(int index, const T& element) {
+ MOZ_ASSERT(index >= 0 && index <= length_);
+ data_[index] = element;
+ }
+
+ // Removes the i'th element without deleting it even if T is a
+ // pointer type; moves all elements above i "down". Returns the
+ // removed element. This function's complexity is linear in the
+ // size of the list.
+ T Remove(int i) {
+ T element = at(i);
+ length_--;
+ while (i < length_) {
+ data_[i] = data_[i + 1];
+ i++;
+ }
+ return element;
+ }
+
+ // Removes the last element without deleting it even if T is a
+ // pointer type. Returns the removed element.
+ inline T RemoveLast() { return Remove(length_ - 1); }
+
+ // Clears the list, setting the capacity and length to 0.
+ inline void Clear() {
+ data_ = nullptr;
+ capacity_ = 0;
+ length_ = 0;
+ }
+
+ // Drops all but the first 'pos' elements from the list.
+ inline void Rewind(int pos) {
+ MOZ_ASSERT(0 <= pos && pos <= length_);
+ length_ = pos;
+ }
+
+ inline bool Contains(const T& elm) const {
+ for (int i = 0; i < length_; i++) {
+ if (data_[i] == elm) return true;
+ }
+ return false;
+ }
+
+ template <typename CompareFunction>
+ void StableSort(CompareFunction cmp, size_t start, size_t length) {
+ js::AutoEnterOOMUnsafeRegion oomUnsafe;
+ T* scratch = static_cast<T*>(js_malloc(length * sizeof(T)));
+ if (!scratch) {
+ oomUnsafe.crash("Irregexp stable sort scratch space");
+ }
+ auto comparator = [cmp](const T& a, const T& b, bool* lessOrEqual) {
+ *lessOrEqual = cmp(&a, &b) <= 0;
+ return true;
+ };
+ MOZ_ALWAYS_TRUE(
+ js::MergeSort(begin() + start, length, scratch, comparator));
+ js_free(scratch);
+ }
+
+ void operator delete(void* pointer) { MOZ_CRASH("unreachable"); }
+ void operator delete(void* pointer, Zone* zone) { MOZ_CRASH("unreachable"); }
+
+ private:
+ T* data_ = nullptr;
+ int capacity_ = 0;
+ int length_ = 0;
+
+ // Increase the capacity of a full list, and add an element.
+ // List must be full already.
+ void ResizeAdd(const T& element, Zone* zone) {
+ MOZ_ASSERT(length_ >= capacity_);
+ // Grow the list capacity by 100%, but make sure to let it grow
+ // even when the capacity is zero (possible initial case).
+ int new_capacity = 1 + 2 * capacity_;
+ // Since the element reference could be an element of the list, copy
+ // it out of the old backing storage before resizing.
+ T temp = element;
+ Resize(new_capacity, zone);
+ data_[length_++] = temp;
+ }
+
+ // Resize the list.
+ void Resize(int new_capacity, Zone* zone) {
+ MOZ_ASSERT(length_ <= new_capacity);
+ static_assert(std::is_trivially_copyable<T>::value);
+ T* new_data = zone->NewArray<T>(new_capacity);
+ if (length_ > 0) {
+ memcpy(new_data, data_, length_ * sizeof(T));
+ }
+ data_ = new_data;
+ capacity_ = new_capacity;
+ }
+
+ ZoneList& operator=(const ZoneList&) = delete;
+ ZoneList() = delete;
+ ZoneList(const ZoneList&) = delete;
+};
+
+// Based on: https://github.com/v8/v8/blob/master/src/zone/zone-allocator.h
+template <typename T>
+class ZoneAllocator {
+ public:
+ using pointer = T*;
+ using const_pointer = const T*;
+ using reference = T&;
+ using const_reference = const T&;
+ using value_type = T;
+ using size_type = size_t;
+ using difference_type = ptrdiff_t;
+ template <class O>
+ struct rebind {
+ using other = ZoneAllocator<O>;
+ };
+
+ explicit ZoneAllocator(Zone* zone) : zone_(zone) {}
+ template <typename U>
+ ZoneAllocator(const ZoneAllocator<U>& other)
+ : ZoneAllocator<T>(other.zone_) {}
+ template <typename U>
+ friend class ZoneAllocator;
+
+ T* allocate(size_t n) { return zone_->NewArray<T>(n); }
+ void deallocate(T* p, size_t) {} // noop for zones
+
+ bool operator==(ZoneAllocator const& other) const {
+ return zone_ == other.zone_;
+ }
+ bool operator!=(ZoneAllocator const& other) const {
+ return zone_ != other.zone_;
+ }
+
+ using Policy = js::LifoAllocPolicy<js::Fallible>;
+ Policy policy() const {
+ return js::LifoAllocPolicy<js::Fallible>(zone_->inner());
+ }
+
+ private:
+ Zone* zone_;
+};
+
+// Zone wrappers for std containers:
+// Origin:
+// https://github.com/v8/v8/blob/5e514a969376dc63517d575b062758efd36cd757/src/zone/zone-containers.h#L25-L169
+
+// A wrapper subclass for std::vector to make it easy to construct one
+// that uses a zone allocator.
+// Used throughout irregexp
+template <typename T>
+class ZoneVector : public std::vector<T, ZoneAllocator<T>> {
+ public:
+ ZoneVector(Zone* zone)
+ : std::vector<T, ZoneAllocator<T>>(ZoneAllocator<T>(zone)) {}
+
+ // Constructs a new vector and fills it with {size} elements, each
+ // constructed via the default constructor.
+ ZoneVector(size_t size, Zone* zone)
+ : std::vector<T, ZoneAllocator<T>>(size, T(), ZoneAllocator<T>(zone)) {}
+
+ // Constructs a new vector and fills it with the contents of the range
+ // [first, last).
+ template <class Iter>
+ ZoneVector(Iter first, Iter last, Zone* zone)
+ : std::vector<T, ZoneAllocator<T>>(first, last, ZoneAllocator<T>(zone)) {}
+};
+
+// A wrapper subclass for std::list to make it easy to construct one
+// that uses a zone allocator.
+// Used in regexp-bytecode-peephole.cc
+template <typename T>
+class ZoneLinkedList : public std::list<T, ZoneAllocator<T>> {
+ public:
+ // Constructs an empty list.
+ explicit ZoneLinkedList(Zone* zone)
+ : std::list<T, ZoneAllocator<T>>(ZoneAllocator<T>(zone)) {}
+};
+
+// A wrapper subclass for std::set to make it easy to construct one that uses
+// a zone allocator.
+// Used in regexp-parser.cc
+template <typename K, typename Compare = std::less<K>>
+class ZoneSet : public std::set<K, Compare, ZoneAllocator<K>> {
+ public:
+ // Constructs an empty set.
+ explicit ZoneSet(Zone* zone)
+ : std::set<K, Compare, ZoneAllocator<K>>(Compare(),
+ ZoneAllocator<K>(zone)) {}
+};
+
+// A wrapper subclass for std::map to make it easy to construct one that uses
+// a zone allocator.
+// Used in regexp-bytecode-peephole.cc
+template <typename K, typename V, typename Compare = std::less<K>>
+class ZoneMap
+ : public std::map<K, V, Compare, ZoneAllocator<std::pair<const K, V>>> {
+ public:
+ // Constructs an empty map.
+ explicit ZoneMap(Zone* zone)
+ : std::map<K, V, Compare, ZoneAllocator<std::pair<const K, V>>>(
+ Compare(), ZoneAllocator<std::pair<const K, V>>(zone)) {}
+};
+
+// A wrapper subclass for std::unordered_map to make it easy to construct one
+// that uses a zone allocator.
+// Used in regexp-bytecode-peephole.cc
+template <typename K, typename V, typename Hash = std::hash<K>,
+ typename KeyEqual = std::equal_to<K>>
+class ZoneUnorderedMap
+ : public std::unordered_map<K, V, Hash, KeyEqual,
+ ZoneAllocator<std::pair<const K, V>>> {
+ public:
+ // Constructs an empty map.
+ explicit ZoneUnorderedMap(Zone* zone, size_t bucket_count = 100)
+ : std::unordered_map<K, V, Hash, KeyEqual,
+ ZoneAllocator<std::pair<const K, V>>>(
+ bucket_count, Hash(), KeyEqual(),
+ ZoneAllocator<std::pair<const K, V>>(zone)) {}
+};
+
+// A wrapper subclass for base::SmallVector to make it easy to construct one
+// that uses a zone allocator.
+template <typename T, size_t kSize>
+class SmallZoneVector : public base::SmallVector<T, kSize, ZoneAllocator<T>> {
+ public:
+ // Constructs an empty small vector.
+ explicit SmallZoneVector(Zone* zone)
+ : base::SmallVector<T, kSize, ZoneAllocator<T>>(ZoneAllocator<T>(zone)) {}
+
+ explicit SmallZoneVector(size_t size, Zone* zone)
+ : base::SmallVector<T, kSize, ZoneAllocator<T>>(
+ size, ZoneAllocator<T>(ZoneAllocator<T>(zone))) {}
+};
+
+} // namespace internal
+} // namespace v8
+
+#endif // V8_UTIL_FLAG_H_