llvm/unittests/ADT/IListIteratorTest.cpp
Duncan P. N. Exon Smith f1f27bb03e ADT: Split out simple_ilist, a simple intrusive list
Split out a new, low-level intrusive list type with clear semantics.
Unlike iplist (and ilist), all operations on simple_ilist are intrusive,
and simple_ilist never takes ownership of its nodes.  This enables an
intuitive API that has the right defaults for intrusive lists.
- insert() takes references (not pointers!) to nodes (in iplist/ilist,
  passing a reference will cause the node to be copied).
- erase() takes only iterators (like std::list), and does not destroy
  the nodes.
- remove() takes only references and has the same behaviour as erase().
- clear() does not destroy the nodes.
- The destructor does not destroy the nodes.
- New API {erase,remove,clear}AndDispose() take an extra Disposer
  functor for callsites that want to call some disposal routine (e.g.,
  std::default_delete).

This list is not currently configurable, and has no callbacks.

The initial motivation was to fix iplist<>::sort to work correctly (even
with callbacks in ilist_traits<>).  iplist<> uses simple_ilist<>::sort
directly.  The new test in unittests/IR/ModuleTest.cpp crashes without
this commit.

Fixing sort() via a low-level layer provided a good opportunity to:
- Unit test the low-level functionality thoroughly.
- Modernize the API, largely inspired by other intrusive list
  implementations.

Here's a sketch of a longer-term plan:
- Create BumpPtrList<>, a non-intrusive list implemented using
  simple_ilist<>, and use it for the Token list in
  lib/Support/YAMLParser.cpp.  This will factor out the only real use of
  createNode().
- Evolve the iplist<> and ilist<> APIs in the direction of
  simple_ilist<>, making allocation/deallocation explicit at call sites
  (similar to simple_ilist<>::eraseAndDispose()).
- Factor out remaining calls to createNode() and deleteNode() and remove
  the customization from ilist_traits<>.
- Transition uses of iplist<>/ilist<> that don't need callbacks over to
  simple_ilist<>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280107 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-30 16:23:55 +00:00

135 lines
3.3 KiB
C++

//===- unittests/ADT/IListIteratorTest.cpp - ilist_iterator unit tests ----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/simple_ilist.h"
#include "gtest/gtest.h"
using namespace llvm;
namespace {
struct Node : ilist_node<Node> {};
TEST(IListIteratorTest, DefaultConstructor) {
simple_ilist<Node>::iterator I;
simple_ilist<Node>::reverse_iterator RI;
simple_ilist<Node>::const_iterator CI;
simple_ilist<Node>::const_reverse_iterator CRI;
EXPECT_EQ(nullptr, I.getNodePtr());
EXPECT_EQ(nullptr, CI.getNodePtr());
EXPECT_EQ(nullptr, RI.getNodePtr());
EXPECT_EQ(nullptr, CRI.getNodePtr());
EXPECT_EQ(I, I);
EXPECT_EQ(I, CI);
EXPECT_EQ(CI, I);
EXPECT_EQ(CI, CI);
EXPECT_EQ(RI, RI);
EXPECT_EQ(RI, CRI);
EXPECT_EQ(CRI, RI);
EXPECT_EQ(CRI, CRI);
EXPECT_EQ(I, RI.getReverse());
EXPECT_EQ(RI, I.getReverse());
}
TEST(IListIteratorTest, Empty) {
simple_ilist<Node> L;
// Check iterators of L.
EXPECT_EQ(L.begin(), L.end());
EXPECT_EQ(L.rbegin(), L.rend());
// Reverse of end should be rend (since the sentinel sits on both sides).
EXPECT_EQ(L.end(), L.rend().getReverse());
EXPECT_EQ(L.rend(), L.end().getReverse());
// Iterators shouldn't match default constructors.
simple_ilist<Node>::iterator I;
simple_ilist<Node>::reverse_iterator RI;
EXPECT_NE(I, L.begin());
EXPECT_NE(I, L.end());
EXPECT_NE(RI, L.rbegin());
EXPECT_NE(RI, L.rend());
}
TEST(IListIteratorTest, OneNodeList) {
simple_ilist<Node> L;
Node A;
L.insert(L.end(), A);
// Check address of reference.
EXPECT_EQ(&A, &*L.begin());
EXPECT_EQ(&A, &*L.rbegin());
// Check that the handle matches.
EXPECT_EQ(L.rbegin().getNodePtr(), L.begin().getNodePtr());
// Check iteration.
EXPECT_EQ(L.end(), ++L.begin());
EXPECT_EQ(L.begin(), --L.end());
EXPECT_EQ(L.rend(), ++L.rbegin());
EXPECT_EQ(L.rbegin(), --L.rend());
// Check conversions.
EXPECT_EQ(L.rbegin(), L.begin().getReverse());
EXPECT_EQ(L.begin(), L.rbegin().getReverse());
}
TEST(IListIteratorTest, TwoNodeList) {
simple_ilist<Node> L;
Node A, B;
L.insert(L.end(), A);
L.insert(L.end(), B);
// Check order.
EXPECT_EQ(&A, &*L.begin());
EXPECT_EQ(&B, &*++L.begin());
EXPECT_EQ(L.end(), ++++L.begin());
EXPECT_EQ(&B, &*L.rbegin());
EXPECT_EQ(&A, &*++L.rbegin());
EXPECT_EQ(L.rend(), ++++L.rbegin());
// Check conversions.
EXPECT_EQ(++L.rbegin(), L.begin().getReverse());
EXPECT_EQ(L.rbegin(), (++L.begin()).getReverse());
EXPECT_EQ(++L.begin(), L.rbegin().getReverse());
EXPECT_EQ(L.begin(), (++L.rbegin()).getReverse());
}
TEST(IListIteratorTest, CheckEraseForward) {
simple_ilist<Node> L;
Node A, B;
L.insert(L.end(), A);
L.insert(L.end(), B);
// Erase nodes.
auto I = L.begin();
EXPECT_EQ(&A, &*I);
L.remove(*I++);
EXPECT_EQ(&B, &*I);
L.remove(*I++);
EXPECT_EQ(L.end(), I);
}
TEST(IListIteratorTest, CheckEraseReverse) {
simple_ilist<Node> L;
Node A, B;
L.insert(L.end(), A);
L.insert(L.end(), B);
// Erase nodes.
auto RI = L.rbegin();
EXPECT_EQ(&B, &*RI);
L.remove(*RI++);
EXPECT_EQ(&A, &*RI);
L.remove(*RI++);
EXPECT_EQ(L.rend(), RI);
}
} // end namespace