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1 //=== - llvm/unittest/Support/TrailingObjectsTest.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/Support/TrailingObjects.h"
11 #include "gtest/gtest.h"
12 
13 using namespace llvm;
14 
15 namespace {
16 // This class, beyond being used by the test case, a nice
17 // demonstration of the intended usage of TrailingObjects, with a
18 // single trailing array.
19 class Class1 final : protected TrailingObjects<Class1, short> {
20   friend TrailingObjects;
21 
22   unsigned NumShorts;
23 
24 protected:
numTrailingObjects(OverloadToken<short>) const25   size_t numTrailingObjects(OverloadToken<short>) const { return NumShorts; }
26 
Class1(int * ShortArray,unsigned NumShorts)27   Class1(int *ShortArray, unsigned NumShorts) : NumShorts(NumShorts) {
28     std::uninitialized_copy(ShortArray, ShortArray + NumShorts,
29                             getTrailingObjects<short>());
30   }
31 
32 public:
create(int * ShortArray,unsigned NumShorts)33   static Class1 *create(int *ShortArray, unsigned NumShorts) {
34     void *Mem = ::operator new(totalSizeToAlloc<short>(NumShorts));
35     return new (Mem) Class1(ShortArray, NumShorts);
36   }
operator delete(void * p)37   void operator delete(void *p) { ::operator delete(p); }
38 
get(unsigned Num) const39   short get(unsigned Num) const { return getTrailingObjects<short>()[Num]; }
40 
numShorts() const41   unsigned numShorts() const { return NumShorts; }
42 
43   // Pull some protected members in as public, for testability.
44   using TrailingObjects::totalSizeToAlloc;
45   using TrailingObjects::additionalSizeToAlloc;
46   using TrailingObjects::getTrailingObjects;
47 };
48 
49 // Here, there are two singular optional object types appended.  Note
50 // that the alignment of Class2 is automatically increased to account
51 // for the alignment requirements of the trailing objects.
52 class Class2 final : protected TrailingObjects<Class2, double, short> {
53   friend TrailingObjects;
54 
55   bool HasShort, HasDouble;
56 
57 protected:
numTrailingObjects(OverloadToken<short>) const58   size_t numTrailingObjects(OverloadToken<short>) const {
59     return HasShort ? 1 : 0;
60   }
numTrailingObjects(OverloadToken<double>) const61   size_t numTrailingObjects(OverloadToken<double>) const {
62     return HasDouble ? 1 : 0;
63   }
64 
Class2(bool HasShort,bool HasDouble)65   Class2(bool HasShort, bool HasDouble)
66       : HasShort(HasShort), HasDouble(HasDouble) {}
67 
68 public:
create(short S=0,double D=0.0)69   static Class2 *create(short S = 0, double D = 0.0) {
70     bool HasShort = S != 0;
71     bool HasDouble = D != 0.0;
72 
73     void *Mem =
74         ::operator new(totalSizeToAlloc<double, short>(HasDouble, HasShort));
75     Class2 *C = new (Mem) Class2(HasShort, HasDouble);
76     if (HasShort)
77       *C->getTrailingObjects<short>() = S;
78     if (HasDouble)
79       *C->getTrailingObjects<double>() = D;
80     return C;
81   }
operator delete(void * p)82   void operator delete(void *p) { ::operator delete(p); }
83 
getShort() const84   short getShort() const {
85     if (!HasShort)
86       return 0;
87     return *getTrailingObjects<short>();
88   }
89 
getDouble() const90   double getDouble() const {
91     if (!HasDouble)
92       return 0.0;
93     return *getTrailingObjects<double>();
94   }
95 
96   // Pull some protected members in as public, for testability.
97   using TrailingObjects::totalSizeToAlloc;
98   using TrailingObjects::additionalSizeToAlloc;
99   using TrailingObjects::getTrailingObjects;
100 };
101 
TEST(TrailingObjects,OneArg)102 TEST(TrailingObjects, OneArg) {
103   int arr[] = {1, 2, 3};
104   Class1 *C = Class1::create(arr, 3);
105   EXPECT_EQ(sizeof(Class1), sizeof(unsigned));
106   EXPECT_EQ(Class1::additionalSizeToAlloc<short>(1), sizeof(short));
107   EXPECT_EQ(Class1::additionalSizeToAlloc<short>(3), sizeof(short) * 3);
108 
109   EXPECT_EQ(Class1::totalSizeToAlloc<short>(1), sizeof(Class1) + sizeof(short));
110   EXPECT_EQ(Class1::totalSizeToAlloc<short>(3),
111             sizeof(Class1) + sizeof(short) * 3);
112 
113   EXPECT_EQ(C->getTrailingObjects<short>(), reinterpret_cast<short *>(C + 1));
114   EXPECT_EQ(C->get(0), 1);
115   EXPECT_EQ(C->get(2), 3);
116   delete C;
117 }
118 
TEST(TrailingObjects,TwoArg)119 TEST(TrailingObjects, TwoArg) {
120   Class2 *C1 = Class2::create(4);
121   Class2 *C2 = Class2::create(0, 4.2);
122 
123   EXPECT_EQ(sizeof(Class2),
124             llvm::alignTo(sizeof(bool) * 2, llvm::alignOf<double>()));
125   EXPECT_EQ(llvm::alignOf<Class2>(), llvm::alignOf<double>());
126 
127   EXPECT_EQ((Class2::additionalSizeToAlloc<double, short>(1, 0)),
128             sizeof(double));
129   EXPECT_EQ((Class2::additionalSizeToAlloc<double, short>(0, 1)),
130             sizeof(short));
131   EXPECT_EQ((Class2::additionalSizeToAlloc<double, short>(3, 1)),
132             sizeof(double) * 3 + sizeof(short));
133 
134   EXPECT_EQ((Class2::totalSizeToAlloc<double, short>(1, 1)),
135             sizeof(Class2) + sizeof(double) + sizeof(short));
136 
137   EXPECT_EQ(C1->getDouble(), 0);
138   EXPECT_EQ(C1->getShort(), 4);
139   EXPECT_EQ(C1->getTrailingObjects<double>(),
140             reinterpret_cast<double *>(C1 + 1));
141   EXPECT_EQ(C1->getTrailingObjects<short>(), reinterpret_cast<short *>(C1 + 1));
142 
143   EXPECT_EQ(C2->getDouble(), 4.2);
144   EXPECT_EQ(C2->getShort(), 0);
145   EXPECT_EQ(C2->getTrailingObjects<double>(),
146             reinterpret_cast<double *>(C2 + 1));
147   EXPECT_EQ(C2->getTrailingObjects<short>(),
148             reinterpret_cast<short *>(reinterpret_cast<double *>(C2 + 1) + 1));
149   delete C1;
150   delete C2;
151 }
152 
153 // This test class is not trying to be a usage demo, just asserting
154 // that three args does actually work too (it's the same code as
155 // handles the second arg, so it's basically covered by the above, but
156 // just in case..)
157 class Class3 final : public TrailingObjects<Class3, double, short, bool> {
158   friend TrailingObjects;
159 
numTrailingObjects(OverloadToken<double>) const160   size_t numTrailingObjects(OverloadToken<double>) const { return 1; }
numTrailingObjects(OverloadToken<short>) const161   size_t numTrailingObjects(OverloadToken<short>) const { return 1; }
162 };
163 
TEST(TrailingObjects,ThreeArg)164 TEST(TrailingObjects, ThreeArg) {
165   EXPECT_EQ((Class3::additionalSizeToAlloc<double, short, bool>(1, 1, 3)),
166             sizeof(double) + sizeof(short) + 3 * sizeof(bool));
167   EXPECT_EQ(sizeof(Class3), llvm::alignTo(1, llvm::alignOf<double>()));
168   std::unique_ptr<char[]> P(new char[1000]);
169   Class3 *C = reinterpret_cast<Class3 *>(P.get());
170   EXPECT_EQ(C->getTrailingObjects<double>(), reinterpret_cast<double *>(C + 1));
171   EXPECT_EQ(C->getTrailingObjects<short>(),
172             reinterpret_cast<short *>(reinterpret_cast<double *>(C + 1) + 1));
173   EXPECT_EQ(
174       C->getTrailingObjects<bool>(),
175       reinterpret_cast<bool *>(
176           reinterpret_cast<short *>(reinterpret_cast<double *>(C + 1) + 1) +
177           1));
178 }
179 
180 class Class4 final : public TrailingObjects<Class4, char, long> {
181   friend TrailingObjects;
numTrailingObjects(OverloadToken<char>) const182   size_t numTrailingObjects(OverloadToken<char>) const { return 1; }
183 };
184 
TEST(TrailingObjects,Realignment)185 TEST(TrailingObjects, Realignment) {
186   EXPECT_EQ((Class4::additionalSizeToAlloc<char, long>(1, 1)),
187             llvm::alignTo(sizeof(long) + 1, llvm::alignOf<long>()));
188   EXPECT_EQ(sizeof(Class4), llvm::alignTo(1, llvm::alignOf<long>()));
189   std::unique_ptr<char[]> P(new char[1000]);
190   Class4 *C = reinterpret_cast<Class4 *>(P.get());
191   EXPECT_EQ(C->getTrailingObjects<char>(), reinterpret_cast<char *>(C + 1));
192   EXPECT_EQ(C->getTrailingObjects<long>(),
193             reinterpret_cast<long *>(llvm::alignAddr(
194                 reinterpret_cast<char *>(C + 1) + 1, llvm::alignOf<long>())));
195 }
196 }
197