xref: /llvm-project/llvm/unittests/ADT/DenseSetTest.cpp (revision fa0f96b083503cb57e12c53d25fe2d33dc5bc242)
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 "gtest/gtest.h"
11 #include "llvm/ADT/DenseSet.h"
12 
13 using namespace llvm;
14 
15 namespace {
16 
17 // Test fixture
18 class DenseSetTest : public testing::Test {
19 };
20 
21 // Test hashing with a set of only two entries.
22 TEST_F(DenseSetTest, DoubleEntrySetTest) {
23   llvm::DenseSet<unsigned> set(2);
24   set.insert(0);
25   set.insert(1);
26   // Original failure was an infinite loop in this call:
27   EXPECT_EQ(0u, set.count(2));
28 }
29 
30 struct TestDenseSetInfo {
31   static inline unsigned getEmptyKey() { return ~0; }
32   static inline unsigned getTombstoneKey() { return ~0U - 1; }
33   static unsigned getHashValue(const unsigned& Val) { return Val * 37U; }
34   static unsigned getHashValue(const char* Val) {
35     return (unsigned)(Val[0] - 'a') * 37U;
36   }
37   static bool isEqual(const unsigned& LHS, const unsigned& RHS) {
38     return LHS == RHS;
39   }
40   static bool isEqual(const char* LHS, const unsigned& RHS) {
41     return (unsigned)(LHS[0] - 'a') == RHS;
42   }
43 };
44 
45 TEST(DenseSetCustomTest, FindAsTest) {
46   DenseSet<unsigned, TestDenseSetInfo> set;
47   set.insert(0);
48   set.insert(1);
49   set.insert(2);
50 
51   // Size tests
52   EXPECT_EQ(3u, set.size());
53 
54   // Normal lookup tests
55   EXPECT_EQ(1u, set.count(1));
56   EXPECT_EQ(0u, *set.find(0));
57   EXPECT_EQ(1u, *set.find(1));
58   EXPECT_EQ(2u, *set.find(2));
59   EXPECT_TRUE(set.find(3) == set.end());
60 
61   // find_as() tests
62   EXPECT_EQ(0u, *set.find_as("a"));
63   EXPECT_EQ(1u, *set.find_as("b"));
64   EXPECT_EQ(2u, *set.find_as("c"));
65   EXPECT_TRUE(set.find_as("d") == set.end());
66 }
67 
68 // Simple class that counts how many moves and copy happens when growing a map
69 struct CountCopyAndMove {
70   static int Move;
71   static int Copy;
72   int Value;
73   CountCopyAndMove(int Value) : Value(Value) {}
74 
75   CountCopyAndMove(const CountCopyAndMove &RHS) {
76     Value = RHS.Value;
77     Copy++;
78   }
79   CountCopyAndMove &operator=(const CountCopyAndMove &RHS) {
80     Value = RHS.Value;
81     Copy++;
82     return *this;
83   }
84   CountCopyAndMove(CountCopyAndMove &&RHS) {
85     Value = RHS.Value;
86     Move++;
87   }
88   CountCopyAndMove &operator=(const CountCopyAndMove &&RHS) {
89     Value = RHS.Value;
90     Move++;
91     return *this;
92   }
93 };
94 int CountCopyAndMove::Copy = 0;
95 int CountCopyAndMove::Move = 0;
96 } // anonymous namespace
97 
98 namespace llvm {
99 // Specialization required to insert a CountCopyAndMove into a DenseSet.
100 template <> struct DenseMapInfo<CountCopyAndMove> {
101   static inline CountCopyAndMove getEmptyKey() { return CountCopyAndMove(-1); };
102   static inline CountCopyAndMove getTombstoneKey() {
103     return CountCopyAndMove(-2);
104   };
105   static unsigned getHashValue(const CountCopyAndMove &Val) {
106     return Val.Value;
107   }
108   static bool isEqual(const CountCopyAndMove &LHS,
109                       const CountCopyAndMove &RHS) {
110     return LHS.Value == RHS.Value;
111   }
112 };
113 }
114 
115 namespace {
116 // Make sure reserve actually gives us enough buckets to insert N items
117 // without increasing allocation size.
118 TEST(DenseSetCustomTest, ReserveTest) {
119   // Test a few different size, 48 is *not* a random choice: we need a value
120   // that is 2/3 of a power of two to stress the grow() condition, and the power
121   // of two has to be at least 64 because of minimum size allocation in the
122   // DenseMa. 66 is a value just above the 64 default init.
123   for (auto Size : {1, 2, 48, 66}) {
124     DenseSet<CountCopyAndMove> Set;
125     Set.reserve(Size);
126     unsigned MemorySize = Set.getMemorySize();
127     CountCopyAndMove::Copy = 0;
128     CountCopyAndMove::Move = 0;
129     for (int i = 0; i < Size; ++i)
130       Set.insert(CountCopyAndMove(i));
131     // Check that we didn't grow
132     EXPECT_EQ(MemorySize, Set.getMemorySize());
133     // Check that move was called the expected number of times
134     EXPECT_EQ(Size, CountCopyAndMove::Move);
135     // Check that no copy occured
136     EXPECT_EQ(0, CountCopyAndMove::Copy);
137   }
138 }
139 }
140