llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_list.h

125 lines
2.7 KiB
C++

//===-- sanitizer_list.h ----------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains implementation of a list class to be used by
// ThreadSanitizer, etc run-times.
//
//===----------------------------------------------------------------------===//
#ifndef SANITIZER_LIST_H
#define SANITIZER_LIST_H
#include "sanitizer_internal_defs.h"
namespace __sanitizer {
// Intrusive singly-linked list with size(), push_back(), push_front()
// pop_front(), append_front() and append_back().
// This class should be a POD (so that it can be put into TLS)
// and an object with all zero fields should represent a valid empty list.
// This class does not have a CTOR, so clear() should be called on all
// non-zero-initialized objects before using.
template<class Item>
struct IntrusiveList {
void clear() {
first_ = last_ = 0;
size_ = 0;
}
bool empty() const { return size_ == 0; }
uptr size() const { return size_; }
void push_back(Item *x) {
if (empty()) {
x->next = 0;
first_ = last_ = x;
size_ = 1;
} else {
x->next = 0;
last_->next = x;
last_ = x;
size_++;
}
}
void push_front(Item *x) {
if (empty()) {
x->next = 0;
first_ = last_ = x;
size_ = 1;
} else {
x->next = first_;
first_ = x;
size_++;
}
}
void pop_front() {
CHECK(!empty());
first_ = first_->next;
if (first_ == 0)
last_ = 0;
size_--;
}
Item *front() { return first_; }
Item *back() { return last_; }
void append_front(IntrusiveList<Item> *l) {
CHECK_NE(this, l);
if (l->empty())
return;
if (empty()) {
*this = *l;
} else if (!l->empty()) {
l->last_->next = first_;
first_ = l->first_;
size_ += l->size();
}
l->clear();
}
void append_back(IntrusiveList<Item> *l) {
CHECK_NE(this, l);
if (l->empty())
return;
if (empty()) {
*this = *l;
} else {
last_->next = l->first_;
last_ = l->last_;
size_ += l->size();
}
l->clear();
}
void CheckConsistency() {
if (size_ == 0) {
CHECK_EQ(first_, 0);
CHECK_EQ(last_, 0);
} else {
uptr count = 0;
for (Item *i = first_; ; i = i->next) {
count++;
if (i == last_) break;
}
CHECK_EQ(size(), count);
CHECK_EQ(last_->next, 0);
}
}
// private, don't use directly.
uptr size_;
Item *first_;
Item *last_;
};
} // namespace __sanitizer
#endif // SANITIZER_LIST_H