unittests/ADT/SmallPtrSetTest.cpp

//===- llvm/unittest/ADT/SmallPtrSetTest.cpp ------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// SmallPtrSet unit tests.
//
//===----------------------------------------------------------------------===//

#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/Support/PointerLikeTypeTraits.h"
#include "gtest/gtest.h"

using namespace llvm;

TEST(SmallPtrSetTest, Assignment) {
  int buf[8];
  for (int i = 0; i < 8; ++i)
    buf[i] = 0;

  SmallPtrSet<int *, 4> s1 = {&buf[0], &buf[1]};
  SmallPtrSet<int *, 4> s2;
  (s2 = s1).insert(&buf[2]);

  // Self assign as well.
  (s2 = static_cast<SmallPtrSet<int *, 4> &>(s2)).insert(&buf[3]);

  s1 = s2;
  EXPECT_EQ(4U, s1.size());
  for (int i = 0; i < 8; ++i)
    if (i < 4)
      EXPECT_TRUE(s1.count(&buf[i]));
    else
      EXPECT_FALSE(s1.count(&buf[i]));

  // Assign and insert with initializer lists, and ones that contain both
  // duplicates and out-of-order elements.
  (s2 = {&buf[6], &buf[7], &buf[6]}).insert({&buf[5], &buf[4]});
  for (int i = 0; i < 8; ++i)
    if (i < 4)
      EXPECT_FALSE(s2.count(&buf[i]));
    else
      EXPECT_TRUE(s2.count(&buf[i]));
}

TEST(SmallPtrSetTest, GrowthTest) {
  int i;
  int buf[8];
  for(i=0; i<8; ++i) buf[i]=0;


  SmallPtrSet<int *, 4> s;
  typedef SmallPtrSet<int *, 4>::iterator iter;

  s.insert(&buf[0]);
  s.insert(&buf[1]);
  s.insert(&buf[2]);
  s.insert(&buf[3]);
  EXPECT_EQ(4U, s.size());

  i = 0;
  for(iter I=s.begin(), E=s.end(); I!=E; ++I, ++i)
      (**I)++;
  EXPECT_EQ(4, i);
  for(i=0; i<8; ++i)
      EXPECT_EQ(i<4?1:0,buf[i]);

  s.insert(&buf[4]);
  s.insert(&buf[5]);
  s.insert(&buf[6]);
  s.insert(&buf[7]);

  i = 0;
  for(iter I=s.begin(), E=s.end(); I!=E; ++I, ++i)
      (**I)++;
  EXPECT_EQ(8, i);
  s.erase(&buf[4]);
  s.erase(&buf[5]);
  s.erase(&buf[6]);
  s.erase(&buf[7]);
  EXPECT_EQ(4U, s.size());

  i = 0;
  for(iter I=s.begin(), E=s.end(); I!=E; ++I, ++i)
      (**I)++;
  EXPECT_EQ(4, i);
  for(i=0; i<8; ++i)
      EXPECT_EQ(i<4?3:1,buf[i]);

  s.clear();
  for(i=0; i<8; ++i) buf[i]=0;
  for(i=0; i<128; ++i) s.insert(&buf[i%8]); // test repeated entires
  EXPECT_EQ(8U, s.size());
  for(iter I=s.begin(), E=s.end(); I!=E; ++I, ++i)
      (**I)++;
  for(i=0; i<8; ++i)
      EXPECT_EQ(1,buf[i]);
}

TEST(SmallPtrSetTest, CopyAndMoveTest) {
  int buf[8];
  for (int i = 0; i < 8; ++i)
    buf[i] = 0;

  SmallPtrSet<int *, 4> s1;
  s1.insert(&buf[0]);
  s1.insert(&buf[1]);
  s1.insert(&buf[2]);
  s1.insert(&buf[3]);
  EXPECT_EQ(4U, s1.size());
  for (int i = 0; i < 8; ++i)
    if (i < 4)
      EXPECT_TRUE(s1.count(&buf[i]));
    else
      EXPECT_FALSE(s1.count(&buf[i]));

  SmallPtrSet<int *, 4> s2(s1);
  EXPECT_EQ(4U, s2.size());
  for (int i = 0; i < 8; ++i)
    if (i < 4)
      EXPECT_TRUE(s2.count(&buf[i]));
    else
      EXPECT_FALSE(s2.count(&buf[i]));

  s1 = s2;
  EXPECT_EQ(4U, s1.size());
  EXPECT_EQ(4U, s2.size());
  for (int i = 0; i < 8; ++i)
    if (i < 4)
      EXPECT_TRUE(s1.count(&buf[i]));
    else
      EXPECT_FALSE(s1.count(&buf[i]));

  SmallPtrSet<int *, 4> s3(std::move(s1));
  EXPECT_EQ(4U, s3.size());
  EXPECT_TRUE(s1.empty());
  for (int i = 0; i < 8; ++i)
    if (i < 4)
      EXPECT_TRUE(s3.count(&buf[i]));
    else
      EXPECT_FALSE(s3.count(&buf[i]));

  // Move assign into the moved-from object. Also test move of a non-small
  // container.
  s3.insert(&buf[4]);
  s3.insert(&buf[5]);
  s3.insert(&buf[6]);
  s3.insert(&buf[7]);
  s1 = std::move(s3);
  EXPECT_EQ(8U, s1.size());
  EXPECT_TRUE(s3.empty());
  for (int i = 0; i < 8; ++i)
    EXPECT_TRUE(s1.count(&buf[i]));

  // Copy assign into a moved-from object.
  s3 = s1;
  EXPECT_EQ(8U, s3.size());
  EXPECT_EQ(8U, s1.size());
  for (int i = 0; i < 8; ++i)
    EXPECT_TRUE(s3.count(&buf[i]));
}

TEST(SmallPtrSetTest, SwapTest) {
  int buf[10];

  SmallPtrSet<int *, 2> a;
  SmallPtrSet<int *, 2> b;

  a.insert(&buf[0]);
  a.insert(&buf[1]);
  b.insert(&buf[2]);

  EXPECT_EQ(2U, a.size());
  EXPECT_EQ(1U, b.size());
  EXPECT_TRUE(a.count(&buf[0]));
  EXPECT_TRUE(a.count(&buf[1]));
  EXPECT_FALSE(a.count(&buf[2]));
  EXPECT_FALSE(a.count(&buf[3]));
  EXPECT_FALSE(b.count(&buf[0]));
  EXPECT_FALSE(b.count(&buf[1]));
  EXPECT_TRUE(b.count(&buf[2]));
  EXPECT_FALSE(b.count(&buf[3]));

  std::swap(a, b);

  EXPECT_EQ(1U, a.size());
  EXPECT_EQ(2U, b.size());
  EXPECT_FALSE(a.count(&buf[0]));
  EXPECT_FALSE(a.count(&buf[1]));
  EXPECT_TRUE(a.count(&buf[2]));
  EXPECT_FALSE(a.count(&buf[3]));
  EXPECT_TRUE(b.count(&buf[0]));
  EXPECT_TRUE(b.count(&buf[1]));
  EXPECT_FALSE(b.count(&buf[2]));
  EXPECT_FALSE(b.count(&buf[3]));

  b.insert(&buf[3]);
  std::swap(a, b);

  EXPECT_EQ(3U, a.size());
  EXPECT_EQ(1U, b.size());
  EXPECT_TRUE(a.count(&buf[0]));
  EXPECT_TRUE(a.count(&buf[1]));
  EXPECT_FALSE(a.count(&buf[2]));
  EXPECT_TRUE(a.count(&buf[3]));
  EXPECT_FALSE(b.count(&buf[0]));
  EXPECT_FALSE(b.count(&buf[1]));
  EXPECT_TRUE(b.count(&buf[2]));
  EXPECT_FALSE(b.count(&buf[3]));

  std::swap(a, b);

  EXPECT_EQ(1U, a.size());
  EXPECT_EQ(3U, b.size());
  EXPECT_FALSE(a.count(&buf[0]));
  EXPECT_FALSE(a.count(&buf[1]));
  EXPECT_TRUE(a.count(&buf[2]));
  EXPECT_FALSE(a.count(&buf[3]));
  EXPECT_TRUE(b.count(&buf[0]));
  EXPECT_TRUE(b.count(&buf[1]));
  EXPECT_FALSE(b.count(&buf[2]));
  EXPECT_TRUE(b.count(&buf[3]));

  a.insert(&buf[4]);
  a.insert(&buf[5]);
  a.insert(&buf[6]);

  std::swap(b, a);

  EXPECT_EQ(3U, a.size());
  EXPECT_EQ(4U, b.size());
  EXPECT_TRUE(b.count(&buf[2]));
  EXPECT_TRUE(b.count(&buf[4]));
  EXPECT_TRUE(b.count(&buf[5]));
  EXPECT_TRUE(b.count(&buf[6]));
  EXPECT_TRUE(a.count(&buf[0]));
  EXPECT_TRUE(a.count(&buf[1]));
  EXPECT_TRUE(a.count(&buf[3]));
}

void checkEraseAndIterators(SmallPtrSetImpl<int*> &S) {
  int buf[3];

  S.insert(&buf[0]);
  S.insert(&buf[1]);
  S.insert(&buf[2]);

  // Iterators must still be valid after erase() calls;
  auto B = S.begin();
  auto M = std::next(B);
  auto E = S.end();
  EXPECT_TRUE(*B == &buf[0] || *B == &buf[1] || *B == &buf[2]);
  EXPECT_TRUE(*M == &buf[0] || *M == &buf[1] || *M == &buf[2]);
  EXPECT_TRUE(*B != *M);
  int *Removable = *std::next(M);
  // No iterator points to Removable now.
  EXPECT_TRUE(Removable == &buf[0] || Removable == &buf[1] ||
              Removable == &buf[2]);
  EXPECT_TRUE(Removable != *B && Removable != *M);

  S.erase(Removable);

  // B,M,E iterators should still be valid
  EXPECT_EQ(B, S.begin());
  EXPECT_EQ(M, std::next(B));
  EXPECT_EQ(E, S.end());
  EXPECT_EQ(std::next(M), E);
}

TEST(SmallPtrSetTest, EraseTest) {
  // Test when set stays small.
  SmallPtrSet<int *, 8> B;
  checkEraseAndIterators(B);

  // Test when set grows big.
  SmallPtrSet<int *, 2> A;
  checkEraseAndIterators(A);
}

// Verify that dereferencing and iteration work.
TEST(SmallPtrSetTest, dereferenceAndIterate) {
  int Ints[] = {0, 1, 2, 3, 4, 5, 6, 7};
  SmallPtrSet<const int *, 4> S;
  for (int &I : Ints) {
    EXPECT_EQ(&I, *S.insert(&I).first);
    EXPECT_EQ(&I, *S.find(&I));
  }

  // Iterate from each and count how many times each element is found.
  int Found[sizeof(Ints)/sizeof(int)] = {0};
  for (int &I : Ints)
    for (auto F = S.find(&I), E = S.end(); F != E; ++F)
      ++Found[*F - Ints];

  // Sort.  We should hit the first element just once and the final element N
  // times.
  llvm::sort(std::begin(Found), std::end(Found));
  for (auto F = std::begin(Found), E = std::end(Found); F != E; ++F)
    EXPECT_EQ(F - Found + 1, *F);
}

// Verify that const pointers work for count and find even when the underlying
// SmallPtrSet is not for a const pointer type.
TEST(SmallPtrSetTest, ConstTest) {
  SmallPtrSet<int *, 8> IntSet;
  int A;
  int *B = &A;
  const int *C = &A;
  IntSet.insert(B);
  EXPECT_EQ(IntSet.count(B), 1u);
  EXPECT_EQ(IntSet.count(C), 1u);
  EXPECT_NE(IntSet.find(B), IntSet.end());
  EXPECT_NE(IntSet.find(C), IntSet.end());
}

// Verify that we automatically get the const version of PointerLikeTypeTraits
// filled in for us, even for a non-pointer type
using TestPair = PointerIntPair<int *, 1>;

TEST(SmallPtrSetTest, ConstNonPtrTest) {
  SmallPtrSet<TestPair, 8> IntSet;
  int A[1];
  TestPair Pair(&A[0], 1);
  IntSet.insert(Pair);
  EXPECT_EQ(IntSet.count(Pair), 1u);
  EXPECT_NE(IntSet.find(Pair), IntSet.end());
}