xref: /llvm-project/llvm/unittests/ADT/DenseSetTest.cpp (revision 4bccb581bfe326e6b3aea4a2340c15cdc13e2008)
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                          SmallDenseSet<unsigned, 1, TestDenseSetInfo>,
61                          SmallDenseSet<unsigned, 4, TestDenseSetInfo>,
62                          const SmallDenseSet<unsigned, 4, TestDenseSetInfo>,
63                          SmallDenseSet<unsigned, 64, TestDenseSetInfo>>
64     DenseSetTestTypes;
65 TYPED_TEST_CASE(DenseSetTest, DenseSetTestTypes);
66 
67 TYPED_TEST(DenseSetTest, FindAsTest) {
68   auto &set = this->Set;
69   // Size tests
70   EXPECT_EQ(3u, set.size());
71 
72   // Normal lookup tests
73   EXPECT_EQ(1u, set.count(1));
74   EXPECT_EQ(0u, *set.find(0));
75   EXPECT_EQ(1u, *set.find(1));
76   EXPECT_EQ(2u, *set.find(2));
77   EXPECT_TRUE(set.find(3) == set.end());
78 
79   // find_as() tests
80   EXPECT_EQ(0u, *set.find_as("a"));
81   EXPECT_EQ(1u, *set.find_as("b"));
82   EXPECT_EQ(2u, *set.find_as("c"));
83   EXPECT_TRUE(set.find_as("d") == set.end());
84 }
85 
86 // Simple class that counts how many moves and copy happens when growing a map
87 struct CountCopyAndMove {
88   static int Move;
89   static int Copy;
90   int Value;
91   CountCopyAndMove(int Value) : Value(Value) {}
92 
93   CountCopyAndMove(const CountCopyAndMove &RHS) {
94     Value = RHS.Value;
95     Copy++;
96   }
97   CountCopyAndMove &operator=(const CountCopyAndMove &RHS) {
98     Value = RHS.Value;
99     Copy++;
100     return *this;
101   }
102   CountCopyAndMove(CountCopyAndMove &&RHS) {
103     Value = RHS.Value;
104     Move++;
105   }
106   CountCopyAndMove &operator=(const CountCopyAndMove &&RHS) {
107     Value = RHS.Value;
108     Move++;
109     return *this;
110   }
111 };
112 int CountCopyAndMove::Copy = 0;
113 int CountCopyAndMove::Move = 0;
114 } // anonymous namespace
115 
116 namespace llvm {
117 // Specialization required to insert a CountCopyAndMove into a DenseSet.
118 template <> struct DenseMapInfo<CountCopyAndMove> {
119   static inline CountCopyAndMove getEmptyKey() { return CountCopyAndMove(-1); };
120   static inline CountCopyAndMove getTombstoneKey() {
121     return CountCopyAndMove(-2);
122   };
123   static unsigned getHashValue(const CountCopyAndMove &Val) {
124     return Val.Value;
125   }
126   static bool isEqual(const CountCopyAndMove &LHS,
127                       const CountCopyAndMove &RHS) {
128     return LHS.Value == RHS.Value;
129   }
130 };
131 }
132 
133 namespace {
134 // Make sure reserve actually gives us enough buckets to insert N items
135 // without increasing allocation size.
136 TEST(DenseSetCustomTest, ReserveTest) {
137   // Test a few different size, 48 is *not* a random choice: we need a value
138   // that is 2/3 of a power of two to stress the grow() condition, and the power
139   // of two has to be at least 64 because of minimum size allocation in the
140   // DenseMa. 66 is a value just above the 64 default init.
141   for (auto Size : {1, 2, 48, 66}) {
142     DenseSet<CountCopyAndMove> Set;
143     Set.reserve(Size);
144     unsigned MemorySize = Set.getMemorySize();
145     CountCopyAndMove::Copy = 0;
146     CountCopyAndMove::Move = 0;
147     for (int i = 0; i < Size; ++i)
148       Set.insert(CountCopyAndMove(i));
149     // Check that we didn't grow
150     EXPECT_EQ(MemorySize, Set.getMemorySize());
151     // Check that move was called the expected number of times
152     EXPECT_EQ(Size, CountCopyAndMove::Move);
153     // Check that no copy occured
154     EXPECT_EQ(0, CountCopyAndMove::Copy);
155   }
156 }
157 }
158