llvm-mirror/include/llvm/ADT/ilist_base.h
Chandler Carruth ae65e281f3 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00

93 lines
2.7 KiB
C++

//===- llvm/ADT/ilist_base.h - Intrusive List Base --------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_ILIST_BASE_H
#define LLVM_ADT_ILIST_BASE_H
#include "llvm/ADT/ilist_node_base.h"
#include <cassert>
namespace llvm {
/// Implementations of list algorithms using ilist_node_base.
template <bool EnableSentinelTracking> class ilist_base {
public:
using node_base_type = ilist_node_base<EnableSentinelTracking>;
static void insertBeforeImpl(node_base_type &Next, node_base_type &N) {
node_base_type &Prev = *Next.getPrev();
N.setNext(&Next);
N.setPrev(&Prev);
Prev.setNext(&N);
Next.setPrev(&N);
}
static void removeImpl(node_base_type &N) {
node_base_type *Prev = N.getPrev();
node_base_type *Next = N.getNext();
Next->setPrev(Prev);
Prev->setNext(Next);
// Not strictly necessary, but helps catch a class of bugs.
N.setPrev(nullptr);
N.setNext(nullptr);
}
static void removeRangeImpl(node_base_type &First, node_base_type &Last) {
node_base_type *Prev = First.getPrev();
node_base_type *Final = Last.getPrev();
Last.setPrev(Prev);
Prev->setNext(&Last);
// Not strictly necessary, but helps catch a class of bugs.
First.setPrev(nullptr);
Final->setNext(nullptr);
}
static void transferBeforeImpl(node_base_type &Next, node_base_type &First,
node_base_type &Last) {
if (&Next == &Last || &First == &Last)
return;
// Position cannot be contained in the range to be transferred.
assert(&Next != &First &&
// Check for the most common mistake.
"Insertion point can't be one of the transferred nodes");
node_base_type &Final = *Last.getPrev();
// Detach from old list/position.
First.getPrev()->setNext(&Last);
Last.setPrev(First.getPrev());
// Splice [First, Final] into its new list/position.
node_base_type &Prev = *Next.getPrev();
Final.setNext(&Next);
First.setPrev(&Prev);
Prev.setNext(&First);
Next.setPrev(&Final);
}
template <class T> static void insertBefore(T &Next, T &N) {
insertBeforeImpl(Next, N);
}
template <class T> static void remove(T &N) { removeImpl(N); }
template <class T> static void removeRange(T &First, T &Last) {
removeRangeImpl(First, Last);
}
template <class T> static void transferBefore(T &Next, T &First, T &Last) {
transferBeforeImpl(Next, First, Last);
}
};
} // end namespace llvm
#endif // LLVM_ADT_ILIST_BASE_H