1 //===- llvm/unittest/DebugInfo/PDB/HashTableTest.cpp ----------------------===//
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/DebugInfo/PDB/Native/HashTable.h"
11 
12 #include "llvm/DebugInfo/PDB/Native/Hash.h"
13 #include "llvm/DebugInfo/PDB/Native/NamedStreamMap.h"
14 #include "llvm/Support/Allocator.h"
15 #include "llvm/Support/BinaryByteStream.h"
16 #include "llvm/Support/BinaryStreamReader.h"
17 #include "llvm/Support/BinaryStreamWriter.h"
18 #include "llvm/Support/StringSaver.h"
19 #include "llvm/Testing/Support/Error.h"
20 
21 #include "gtest/gtest.h"
22 
23 #include <vector>
24 
25 using namespace llvm;
26 using namespace llvm::pdb;
27 using namespace llvm::support;
28 
29 namespace {
30 
31 class HashTableInternals : public HashTable<uint32_t> {
32 public:
33   using HashTable::Buckets;
34   using HashTable::Present;
35   using HashTable::Deleted;
36 };
37 }
38 
39 TEST(HashTableTest, TestSimple) {
40   HashTableInternals Table;
41   EXPECT_EQ(0u, Table.size());
42   EXPECT_GT(Table.capacity(), 0u);
43 
44   Table.set_as(3u, 7);
45   EXPECT_EQ(1u, Table.size());
46   ASSERT_NE(Table.end(), Table.find_as(3u));
47   EXPECT_EQ(7u, Table.get(3u));
48 }
49 
50 TEST(HashTableTest, TestCollision) {
51   HashTableInternals Table;
52   EXPECT_EQ(0u, Table.size());
53   EXPECT_GT(Table.capacity(), 0u);
54 
55   // We use knowledge of the hash table's implementation details to make sure
56   // to add another value that is the equivalent to the first value modulo the
57   // hash table's capacity.
58   uint32_t N1 = Table.capacity() + 1;
59   uint32_t N2 = 2 * N1;
60 
61   Table.set_as(N1, 7);
62   Table.set_as(N2, 12);
63   EXPECT_EQ(2u, Table.size());
64   ASSERT_NE(Table.end(), Table.find_as(N1));
65   ASSERT_NE(Table.end(), Table.find_as(N2));
66 
67   EXPECT_EQ(7u, Table.get(N1));
68   EXPECT_EQ(12u, Table.get(N2));
69 }
70 
71 TEST(HashTableTest, TestRemove) {
72   HashTableInternals Table;
73   EXPECT_EQ(0u, Table.size());
74   EXPECT_GT(Table.capacity(), 0u);
75 
76   Table.set_as(1u, 2);
77   Table.set_as(3u, 4);
78   EXPECT_EQ(2u, Table.size());
79   ASSERT_NE(Table.end(), Table.find_as(1u));
80   ASSERT_NE(Table.end(), Table.find_as(3u));
81 
82   EXPECT_EQ(2u, Table.get(1u));
83   EXPECT_EQ(4u, Table.get(3u));
84 }
85 
86 TEST(HashTableTest, TestCollisionAfterMultipleProbes) {
87   HashTableInternals Table;
88   EXPECT_EQ(0u, Table.size());
89   EXPECT_GT(Table.capacity(), 0u);
90 
91   // Probing looks for the first available slot.  A slot may already be filled
92   // as a result of an item with a *different* hash value already being there.
93   // Test that when this happens, the probe still finds the value.
94   uint32_t N1 = Table.capacity() + 1;
95   uint32_t N2 = N1 + 1;
96   uint32_t N3 = 2 * N1;
97 
98   Table.set_as(N1, 7);
99   Table.set_as(N2, 11);
100   Table.set_as(N3, 13);
101   EXPECT_EQ(3u, Table.size());
102   ASSERT_NE(Table.end(), Table.find_as(N1));
103   ASSERT_NE(Table.end(), Table.find_as(N2));
104   ASSERT_NE(Table.end(), Table.find_as(N3));
105 
106   EXPECT_EQ(7u, Table.get(N1));
107   EXPECT_EQ(11u, Table.get(N2));
108   EXPECT_EQ(13u, Table.get(N3));
109 }
110 
111 TEST(HashTableTest, Grow) {
112   // So that we are independent of the load factor, `capacity` items, which is
113   // guaranteed to trigger a grow.  Then verify that the size is the same, the
114   // capacity is larger, and all the original items are still in the table.
115 
116   HashTableInternals Table;
117   uint32_t OldCapacity = Table.capacity();
118   for (uint32_t I = 0; I < OldCapacity; ++I) {
119     Table.set_as(OldCapacity + I * 2 + 1, I * 2 + 3);
120   }
121   EXPECT_EQ(OldCapacity, Table.size());
122   EXPECT_GT(Table.capacity(), OldCapacity);
123   for (uint32_t I = 0; I < OldCapacity; ++I) {
124     ASSERT_NE(Table.end(), Table.find_as(OldCapacity + I * 2 + 1));
125     EXPECT_EQ(I * 2 + 3, Table.get(OldCapacity + I * 2 + 1));
126   }
127 }
128 
129 TEST(HashTableTest, Serialization) {
130   HashTableInternals Table;
131   uint32_t Cap = Table.capacity();
132   for (uint32_t I = 0; I < Cap; ++I) {
133     Table.set_as(Cap + I * 2 + 1, I * 2 + 3);
134   }
135 
136   std::vector<uint8_t> Buffer(Table.calculateSerializedLength());
137   MutableBinaryByteStream Stream(Buffer, little);
138   BinaryStreamWriter Writer(Stream);
139   EXPECT_THAT_ERROR(Table.commit(Writer), Succeeded());
140   // We should have written precisely the number of bytes we calculated earlier.
141   EXPECT_EQ(Buffer.size(), Writer.getOffset());
142 
143   HashTableInternals Table2;
144   BinaryStreamReader Reader(Stream);
145   EXPECT_THAT_ERROR(Table2.load(Reader), Succeeded());
146   // We should have read precisely the number of bytes we calculated earlier.
147   EXPECT_EQ(Buffer.size(), Reader.getOffset());
148 
149   EXPECT_EQ(Table.size(), Table2.size());
150   EXPECT_EQ(Table.capacity(), Table2.capacity());
151   EXPECT_EQ(Table.Buckets, Table2.Buckets);
152   EXPECT_EQ(Table.Present, Table2.Present);
153   EXPECT_EQ(Table.Deleted, Table2.Deleted);
154 }
155 
156 TEST(HashTableTest, NamedStreamMap) {
157   std::vector<StringRef> Streams = {"One",  "Two", "Three", "Four",
158                                     "Five", "Six", "Seven"};
159   StringMap<uint32_t> ExpectedIndices;
160   for (uint32_t I = 0; I < Streams.size(); ++I)
161     ExpectedIndices[Streams[I]] = I + 1;
162 
163   // To verify the hash table actually works, we want to verify that insertion
164   // order doesn't matter.  So try inserting in every possible order of 7 items.
165   do {
166     NamedStreamMap NSM;
167     for (StringRef S : Streams)
168       NSM.set(S, ExpectedIndices[S]);
169 
170     EXPECT_EQ(Streams.size(), NSM.size());
171 
172     uint32_t N;
173     EXPECT_TRUE(NSM.get("One", N));
174     EXPECT_EQ(1U, N);
175 
176     EXPECT_TRUE(NSM.get("Two", N));
177     EXPECT_EQ(2U, N);
178 
179     EXPECT_TRUE(NSM.get("Three", N));
180     EXPECT_EQ(3U, N);
181 
182     EXPECT_TRUE(NSM.get("Four", N));
183     EXPECT_EQ(4U, N);
184 
185     EXPECT_TRUE(NSM.get("Five", N));
186     EXPECT_EQ(5U, N);
187 
188     EXPECT_TRUE(NSM.get("Six", N));
189     EXPECT_EQ(6U, N);
190 
191     EXPECT_TRUE(NSM.get("Seven", N));
192     EXPECT_EQ(7U, N);
193   } while (std::next_permutation(Streams.begin(), Streams.end()));
194 }
195 
196 namespace {
197 struct FooBar {
198   uint32_t X;
199   uint32_t Y;
200 };
201 
202 } // namespace
203 
204 namespace llvm {
205 namespace pdb {
206 template <> struct PdbHashTraits<FooBar> {
207   std::vector<char> Buffer;
208 
209   PdbHashTraits() { Buffer.push_back(0); }
210 
211   uint32_t hashLookupKey(StringRef S) const {
212     return llvm::pdb::hashStringV1(S);
213   }
214 
215   StringRef storageKeyToLookupKey(uint32_t N) const {
216     if (N >= Buffer.size())
217       return StringRef();
218 
219     return StringRef(Buffer.data() + N);
220   }
221 
222   uint32_t lookupKeyToStorageKey(StringRef S) {
223     uint32_t N = Buffer.size();
224     Buffer.insert(Buffer.end(), S.begin(), S.end());
225     Buffer.push_back('\0');
226     return N;
227   }
228 };
229 } // namespace pdb
230 } // namespace llvm
231 
232 TEST(HashTableTest, NonTrivialValueType) {
233   HashTable<FooBar> Table;
234   uint32_t Cap = Table.capacity();
235   for (uint32_t I = 0; I < Cap; ++I) {
236     FooBar F;
237     F.X = I;
238     F.Y = I + 1;
239     Table.set_as(utostr(I), F);
240   }
241 
242   std::vector<uint8_t> Buffer(Table.calculateSerializedLength());
243   MutableBinaryByteStream Stream(Buffer, little);
244   BinaryStreamWriter Writer(Stream);
245   EXPECT_THAT_ERROR(Table.commit(Writer), Succeeded());
246   // We should have written precisely the number of bytes we calculated earlier.
247   EXPECT_EQ(Buffer.size(), Writer.getOffset());
248 
249   HashTable<FooBar> Table2;
250   BinaryStreamReader Reader(Stream);
251   EXPECT_THAT_ERROR(Table2.load(Reader), Succeeded());
252   // We should have read precisely the number of bytes we calculated earlier.
253   EXPECT_EQ(Buffer.size(), Reader.getOffset());
254 
255   EXPECT_EQ(Table.size(), Table2.size());
256   EXPECT_EQ(Table.capacity(), Table2.capacity());
257   // EXPECT_EQ(Table.Buckets, Table2.Buckets);
258   // EXPECT_EQ(Table.Present, Table2.Present);
259   // EXPECT_EQ(Table.Deleted, Table2.Deleted);
260 }
261