xref: /llvm-project/llvm/unittests/ADT/DenseSetTest.cpp (revision f12b1c700c3a18fc2a9bccc766da2ae425b97171)
1 //===- llvm/unittest/ADT/DenseSetTest.cpp - DenseSet unit tests --*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "llvm/ADT/DenseSet.h"
11 #include "gtest/gtest.h"
12 #include <type_traits>
13 
14 using namespace llvm;
15 
16 namespace {
17 
18 // Test hashing with a set of only two entries.
19 TEST(DenseSetTest, DoubleEntrySetTest) {
20   llvm::DenseSet<unsigned> set(2);
21   set.insert(0);
22   set.insert(1);
23   // Original failure was an infinite loop in this call:
24   EXPECT_EQ(0u, set.count(2));
25 }
26 
27 struct TestDenseSetInfo {
28   static inline unsigned getEmptyKey() { return ~0; }
29   static inline unsigned getTombstoneKey() { return ~0U - 1; }
30   static unsigned getHashValue(const unsigned& Val) { return Val * 37U; }
31   static unsigned getHashValue(const char* Val) {
32     return (unsigned)(Val[0] - 'a') * 37U;
33   }
34   static bool isEqual(const unsigned& LHS, const unsigned& RHS) {
35     return LHS == RHS;
36   }
37   static bool isEqual(const char* LHS, const unsigned& RHS) {
38     return (unsigned)(LHS[0] - 'a') == RHS;
39   }
40 };
41 
42 // Test fixture
43 template <typename T> class DenseSetTest : public testing::Test {
44 protected:
45   T Set = GetTestSet();
46 
47 private:
48   static T GetTestSet() {
49     typename std::remove_const<T>::type Set;
50     Set.insert(0);
51     Set.insert(1);
52     Set.insert(2);
53     return Set;
54   }
55 };
56 
57 // Register these types for testing.
58 typedef ::testing::Types<DenseSet<unsigned, TestDenseSetInfo>,
59                          const DenseSet<unsigned, TestDenseSetInfo>>
60     DenseSetTestTypes;
61 TYPED_TEST_CASE(DenseSetTest, DenseSetTestTypes);
62 
63 TYPED_TEST(DenseSetTest, FindAsTest) {
64   auto &set = this->Set;
65   // Size tests
66   EXPECT_EQ(3u, set.size());
67 
68   // Normal lookup tests
69   EXPECT_EQ(1u, set.count(1));
70   EXPECT_EQ(0u, *set.find(0));
71   EXPECT_EQ(1u, *set.find(1));
72   EXPECT_EQ(2u, *set.find(2));
73   EXPECT_TRUE(set.find(3) == set.end());
74 
75   // find_as() tests
76   EXPECT_EQ(0u, *set.find_as("a"));
77   EXPECT_EQ(1u, *set.find_as("b"));
78   EXPECT_EQ(2u, *set.find_as("c"));
79   EXPECT_TRUE(set.find_as("d") == set.end());
80 }
81 
82 // Simple class that counts how many moves and copy happens when growing a map
83 struct CountCopyAndMove {
84   static int Move;
85   static int Copy;
86   int Value;
87   CountCopyAndMove(int Value) : Value(Value) {}
88 
89   CountCopyAndMove(const CountCopyAndMove &RHS) {
90     Value = RHS.Value;
91     Copy++;
92   }
93   CountCopyAndMove &operator=(const CountCopyAndMove &RHS) {
94     Value = RHS.Value;
95     Copy++;
96     return *this;
97   }
98   CountCopyAndMove(CountCopyAndMove &&RHS) {
99     Value = RHS.Value;
100     Move++;
101   }
102   CountCopyAndMove &operator=(const CountCopyAndMove &&RHS) {
103     Value = RHS.Value;
104     Move++;
105     return *this;
106   }
107 };
108 int CountCopyAndMove::Copy = 0;
109 int CountCopyAndMove::Move = 0;
110 } // anonymous namespace
111 
112 namespace llvm {
113 // Specialization required to insert a CountCopyAndMove into a DenseSet.
114 template <> struct DenseMapInfo<CountCopyAndMove> {
115   static inline CountCopyAndMove getEmptyKey() { return CountCopyAndMove(-1); };
116   static inline CountCopyAndMove getTombstoneKey() {
117     return CountCopyAndMove(-2);
118   };
119   static unsigned getHashValue(const CountCopyAndMove &Val) {
120     return Val.Value;
121   }
122   static bool isEqual(const CountCopyAndMove &LHS,
123                       const CountCopyAndMove &RHS) {
124     return LHS.Value == RHS.Value;
125   }
126 };
127 }
128 
129 namespace {
130 // Make sure reserve actually gives us enough buckets to insert N items
131 // without increasing allocation size.
132 TEST(DenseSetCustomTest, ReserveTest) {
133   // Test a few different size, 48 is *not* a random choice: we need a value
134   // that is 2/3 of a power of two to stress the grow() condition, and the power
135   // of two has to be at least 64 because of minimum size allocation in the
136   // DenseMa. 66 is a value just above the 64 default init.
137   for (auto Size : {1, 2, 48, 66}) {
138     DenseSet<CountCopyAndMove> Set;
139     Set.reserve(Size);
140     unsigned MemorySize = Set.getMemorySize();
141     CountCopyAndMove::Copy = 0;
142     CountCopyAndMove::Move = 0;
143     for (int i = 0; i < Size; ++i)
144       Set.insert(CountCopyAndMove(i));
145     // Check that we didn't grow
146     EXPECT_EQ(MemorySize, Set.getMemorySize());
147     // Check that move was called the expected number of times
148     EXPECT_EQ(Size, CountCopyAndMove::Move);
149     // Check that no copy occured
150     EXPECT_EQ(0, CountCopyAndMove::Copy);
151   }
152 }
153 }
154