1 //=== - llvm/unittest/Support/TrailingObjectsTest.cpp ---------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "llvm/Support/TrailingObjects.h"
10 #include "gtest/gtest.h"
11
12 using namespace llvm;
13
14 namespace {
15 // This class, beyond being used by the test case, a nice
16 // demonstration of the intended usage of TrailingObjects, with a
17 // single trailing array.
18 class Class1 final : protected TrailingObjects<Class1, short> {
19 friend TrailingObjects;
20
21 unsigned NumShorts;
22
23 protected:
numTrailingObjects(OverloadToken<short>) const24 size_t numTrailingObjects(OverloadToken<short>) const { return NumShorts; }
25
Class1(int * ShortArray,unsigned NumShorts)26 Class1(int *ShortArray, unsigned NumShorts) : NumShorts(NumShorts) {
27 std::uninitialized_copy(ShortArray, ShortArray + NumShorts,
28 getTrailingObjects<short>());
29 }
30
31 public:
create(int * ShortArray,unsigned NumShorts)32 static Class1 *create(int *ShortArray, unsigned NumShorts) {
33 void *Mem = ::operator new(totalSizeToAlloc<short>(NumShorts));
34 return new (Mem) Class1(ShortArray, NumShorts);
35 }
operator delete(void * p)36 void operator delete(void *p) { ::operator delete(p); }
37
get(unsigned Num) const38 short get(unsigned Num) const { return getTrailingObjects<short>()[Num]; }
39
numShorts() const40 unsigned numShorts() const { return NumShorts; }
41
42 // Pull some protected members in as public, for testability.
43 template <typename... Ty>
44 using FixedSizeStorage = TrailingObjects::FixedSizeStorage<Ty...>;
45
46 using TrailingObjects::totalSizeToAlloc;
47 using TrailingObjects::additionalSizeToAlloc;
48 using TrailingObjects::getTrailingObjects;
49 };
50
51 // Here, there are two singular optional object types appended. Note
52 // that the alignment of Class2 is automatically increased to account
53 // for the alignment requirements of the trailing objects.
54 class Class2 final : protected TrailingObjects<Class2, double, short> {
55 friend TrailingObjects;
56
57 bool HasShort, HasDouble;
58
59 protected:
numTrailingObjects(OverloadToken<short>) const60 size_t numTrailingObjects(OverloadToken<short>) const {
61 return HasShort ? 1 : 0;
62 }
numTrailingObjects(OverloadToken<double>) const63 size_t numTrailingObjects(OverloadToken<double>) const {
64 return HasDouble ? 1 : 0;
65 }
66
Class2(bool HasShort,bool HasDouble)67 Class2(bool HasShort, bool HasDouble)
68 : HasShort(HasShort), HasDouble(HasDouble) {}
69
70 public:
create(short S=0,double D=0.0)71 static Class2 *create(short S = 0, double D = 0.0) {
72 bool HasShort = S != 0;
73 bool HasDouble = D != 0.0;
74
75 void *Mem =
76 ::operator new(totalSizeToAlloc<double, short>(HasDouble, HasShort));
77 Class2 *C = new (Mem) Class2(HasShort, HasDouble);
78 if (HasShort)
79 *C->getTrailingObjects<short>() = S;
80 if (HasDouble)
81 *C->getTrailingObjects<double>() = D;
82 return C;
83 }
operator delete(void * p)84 void operator delete(void *p) { ::operator delete(p); }
85
getShort() const86 short getShort() const {
87 if (!HasShort)
88 return 0;
89 return *getTrailingObjects<short>();
90 }
91
getDouble() const92 double getDouble() const {
93 if (!HasDouble)
94 return 0.0;
95 return *getTrailingObjects<double>();
96 }
97
98 // Pull some protected members in as public, for testability.
99 template <typename... Ty>
100 using FixedSizeStorage = TrailingObjects::FixedSizeStorage<Ty...>;
101
102 using TrailingObjects::totalSizeToAlloc;
103 using TrailingObjects::additionalSizeToAlloc;
104 using TrailingObjects::getTrailingObjects;
105 };
106
TEST(TrailingObjects,OneArg)107 TEST(TrailingObjects, OneArg) {
108 int arr[] = {1, 2, 3};
109 Class1 *C = Class1::create(arr, 3);
110 EXPECT_EQ(sizeof(Class1), sizeof(unsigned));
111 EXPECT_EQ(Class1::additionalSizeToAlloc<short>(1), sizeof(short));
112 EXPECT_EQ(Class1::additionalSizeToAlloc<short>(3), sizeof(short) * 3);
113
114 EXPECT_EQ(alignof(Class1),
115 alignof(Class1::FixedSizeStorage<short>::with_counts<1>::type));
116 EXPECT_EQ(sizeof(Class1::FixedSizeStorage<short>::with_counts<1>::type),
117 llvm::alignTo(Class1::totalSizeToAlloc<short>(1), alignof(Class1)));
118 EXPECT_EQ(Class1::totalSizeToAlloc<short>(1), sizeof(Class1) + sizeof(short));
119
120 EXPECT_EQ(alignof(Class1),
121 alignof(Class1::FixedSizeStorage<short>::with_counts<3>::type));
122 EXPECT_EQ(sizeof(Class1::FixedSizeStorage<short>::with_counts<3>::type),
123 llvm::alignTo(Class1::totalSizeToAlloc<short>(3), alignof(Class1)));
124 EXPECT_EQ(Class1::totalSizeToAlloc<short>(3),
125 sizeof(Class1) + sizeof(short) * 3);
126
127 EXPECT_EQ(C->getTrailingObjects<short>(), reinterpret_cast<short *>(C + 1));
128 EXPECT_EQ(C->get(0), 1);
129 EXPECT_EQ(C->get(2), 3);
130 delete C;
131 }
132
TEST(TrailingObjects,TwoArg)133 TEST(TrailingObjects, TwoArg) {
134 Class2 *C1 = Class2::create(4);
135 Class2 *C2 = Class2::create(0, 4.2);
136
137 EXPECT_EQ(sizeof(Class2), llvm::alignTo(sizeof(bool) * 2, alignof(double)));
138 EXPECT_EQ(alignof(Class2), alignof(double));
139
140 EXPECT_EQ((Class2::additionalSizeToAlloc<double, short>(1, 0)),
141 sizeof(double));
142 EXPECT_EQ((Class2::additionalSizeToAlloc<double, short>(0, 1)),
143 sizeof(short));
144 EXPECT_EQ((Class2::additionalSizeToAlloc<double, short>(3, 1)),
145 sizeof(double) * 3 + sizeof(short));
146
147 EXPECT_EQ(
148 alignof(Class2),
149 (alignof(
150 Class2::FixedSizeStorage<double, short>::with_counts<1, 1>::type)));
151 EXPECT_EQ(
152 sizeof(Class2::FixedSizeStorage<double, short>::with_counts<1, 1>::type),
153 llvm::alignTo(Class2::totalSizeToAlloc<double, short>(1, 1),
154 alignof(Class2)));
155 EXPECT_EQ((Class2::totalSizeToAlloc<double, short>(1, 1)),
156 sizeof(Class2) + sizeof(double) + sizeof(short));
157
158 EXPECT_EQ(C1->getDouble(), 0);
159 EXPECT_EQ(C1->getShort(), 4);
160 EXPECT_EQ(C1->getTrailingObjects<double>(),
161 reinterpret_cast<double *>(C1 + 1));
162 EXPECT_EQ(C1->getTrailingObjects<short>(), reinterpret_cast<short *>(C1 + 1));
163
164 EXPECT_EQ(C2->getDouble(), 4.2);
165 EXPECT_EQ(C2->getShort(), 0);
166 EXPECT_EQ(C2->getTrailingObjects<double>(),
167 reinterpret_cast<double *>(C2 + 1));
168 EXPECT_EQ(C2->getTrailingObjects<short>(),
169 reinterpret_cast<short *>(reinterpret_cast<double *>(C2 + 1) + 1));
170 delete C1;
171 delete C2;
172 }
173
174 // This test class is not trying to be a usage demo, just asserting
175 // that three args does actually work too (it's the same code as
176 // handles the second arg, so it's basically covered by the above, but
177 // just in case..)
178 class Class3 final : public TrailingObjects<Class3, double, short, bool> {
179 friend TrailingObjects;
180
numTrailingObjects(OverloadToken<double>) const181 size_t numTrailingObjects(OverloadToken<double>) const { return 1; }
numTrailingObjects(OverloadToken<short>) const182 size_t numTrailingObjects(OverloadToken<short>) const { return 1; }
183 };
184
TEST(TrailingObjects,ThreeArg)185 TEST(TrailingObjects, ThreeArg) {
186 EXPECT_EQ((Class3::additionalSizeToAlloc<double, short, bool>(1, 1, 3)),
187 sizeof(double) + sizeof(short) + 3 * sizeof(bool));
188 EXPECT_EQ(sizeof(Class3), llvm::alignTo(1, alignof(double)));
189
190 EXPECT_EQ(
191 alignof(Class3),
192 (alignof(Class3::FixedSizeStorage<double, short,
193 bool>::with_counts<1, 1, 3>::type)));
194 EXPECT_EQ(
195 sizeof(Class3::FixedSizeStorage<double, short,
196 bool>::with_counts<1, 1, 3>::type),
197 llvm::alignTo(Class3::totalSizeToAlloc<double, short, bool>(1, 1, 3),
198 alignof(Class3)));
199
200 std::unique_ptr<char[]> P(new char[1000]);
201 Class3 *C = reinterpret_cast<Class3 *>(P.get());
202 EXPECT_EQ(C->getTrailingObjects<double>(), reinterpret_cast<double *>(C + 1));
203 EXPECT_EQ(C->getTrailingObjects<short>(),
204 reinterpret_cast<short *>(reinterpret_cast<double *>(C + 1) + 1));
205 EXPECT_EQ(
206 C->getTrailingObjects<bool>(),
207 reinterpret_cast<bool *>(
208 reinterpret_cast<short *>(reinterpret_cast<double *>(C + 1) + 1) +
209 1));
210 }
211
212 class Class4 final : public TrailingObjects<Class4, char, long> {
213 friend TrailingObjects;
numTrailingObjects(OverloadToken<char>) const214 size_t numTrailingObjects(OverloadToken<char>) const { return 1; }
215 };
216
TEST(TrailingObjects,Realignment)217 TEST(TrailingObjects, Realignment) {
218 EXPECT_EQ((Class4::additionalSizeToAlloc<char, long>(1, 1)),
219 llvm::alignTo(sizeof(long) + 1, alignof(long)));
220 EXPECT_EQ(sizeof(Class4), llvm::alignTo(1, alignof(long)));
221
222 EXPECT_EQ(
223 alignof(Class4),
224 (alignof(Class4::FixedSizeStorage<char, long>::with_counts<1, 1>::type)));
225 EXPECT_EQ(
226 sizeof(Class4::FixedSizeStorage<char, long>::with_counts<1, 1>::type),
227 llvm::alignTo(Class4::totalSizeToAlloc<char, long>(1, 1),
228 alignof(Class4)));
229
230 std::unique_ptr<char[]> P(new char[1000]);
231 Class4 *C = reinterpret_cast<Class4 *>(P.get());
232 EXPECT_EQ(C->getTrailingObjects<char>(), reinterpret_cast<char *>(C + 1));
233 EXPECT_EQ(C->getTrailingObjects<long>(),
234 reinterpret_cast<long *>(llvm::alignAddr(
235 reinterpret_cast<char *>(C + 1) + 1, Align::Of<long>())));
236 }
237 }
238
239 // Test the use of TrailingObjects with a template class. This
240 // previously failed to compile due to a bug in MSVC's member access
241 // control/lookup handling for OverloadToken.
242 template <typename Derived>
243 class Class5Tmpl : private llvm::TrailingObjects<Derived, float, int> {
244 using TrailingObjects = typename llvm::TrailingObjects<Derived, float>;
245 friend TrailingObjects;
246
numTrailingObjects(typename TrailingObjects::template OverloadToken<float>) const247 size_t numTrailingObjects(
248 typename TrailingObjects::template OverloadToken<float>) const {
249 return 1;
250 }
251
numTrailingObjects(typename TrailingObjects::template OverloadToken<int>) const252 size_t numTrailingObjects(
253 typename TrailingObjects::template OverloadToken<int>) const {
254 return 2;
255 }
256 };
257
258 class Class5 : public Class5Tmpl<Class5> {};
259