1 //=== - llvm/unittest/Support/AlignOfTest.cpp - Alignment utility tests ---===//
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 #ifdef _MSC_VER
11 // Disable warnings about alignment-based structure padding.
12 // This must be above the includes to suppress warnings in included templates.
13 #pragma warning(disable:4324)
14 #endif
15 
16 #include "llvm/Support/AlignOf.h"
17 #include "llvm/Support/Compiler.h"
18 #include "gtest/gtest.h"
19 
20 using namespace llvm;
21 
22 namespace {
23 // Disable warnings about questionable type definitions.
24 // We're testing that even questionable types work with the alignment utilities.
25 #ifdef _MSC_VER
26 #pragma warning(disable:4584)
27 #endif
28 
29 // Suppress direct base '{anonymous}::S1' inaccessible in '{anonymous}::D9'
30 // due to ambiguity warning.
31 #ifdef __clang__
32 #pragma clang diagnostic ignored "-Wunknown-pragmas"
33 #pragma clang diagnostic ignored "-Winaccessible-base"
34 #elif ((__GNUC__ * 100) + __GNUC_MINOR__) >= 402
35 // Pragma based warning suppression was introduced in GGC 4.2.  Additionally
36 // this warning is "enabled by default".  The warning still appears if -Wall is
37 // suppressed.  Apparently GCC suppresses it when -w is specifed, which is odd.
38 #pragma GCC diagnostic warning "-w"
39 #endif
40 
41 // Define some fixed alignment types to use in these tests.
42 struct LLVM_ALIGNAS(1) A1 {};
43 struct LLVM_ALIGNAS(2) A2 {};
44 struct LLVM_ALIGNAS(4) A4 {};
45 struct LLVM_ALIGNAS(8) A8 {};
46 
47 struct S1 {};
48 struct S2 { char a; };
49 struct S3 { int x; };
50 struct S4 { double y; };
51 struct S5 { A1 a1; A2 a2; A4 a4; A8 a8; };
52 struct S6 { double f(); };
53 struct D1 : S1 {};
54 struct D2 : S6 { float g(); };
55 struct D3 : S2 {};
56 struct D4 : S2 { int x; };
57 struct D5 : S3 { char c; };
58 struct D6 : S2, S3 {};
59 struct D7 : S1, S3 {};
60 struct D8 : S1, D4, D5 { double x[2]; };
61 struct D9 : S1, D1 { S1 s1; };
62 struct V1 { virtual ~V1(); };
63 struct V2 { int x; virtual ~V2(); };
64 struct V3 : V1 {
65   ~V3() override;
66 };
67 struct V4 : virtual V2 { int y;
68   ~V4() override;
69 };
70 struct V5 : V4, V3 { double z;
71   ~V5() override;
72 };
73 struct V6 : S1 { virtual ~V6(); };
74 struct V7 : virtual V2, virtual V6 {
75   ~V7() override;
76 };
77 struct V8 : V5, virtual V6, V7 { double zz;
78   ~V8() override;
79 };
80 
81 double S6::f() { return 0.0; }
82 float D2::g() { return 0.0f; }
83 V1::~V1() {}
84 V2::~V2() {}
85 V3::~V3() {}
86 V4::~V4() {}
87 V5::~V5() {}
88 V6::~V6() {}
89 V7::~V7() {}
90 V8::~V8() {}
91 
92 template <typename M> struct T { M m; };
93 
94 typedef uint8_t t1;
95 typedef uint16_t t2;
96 typedef uint32_t t3;
97 typedef uint64_t t4;
98 typedef int8_t t5;
99 typedef int16_t t6;
100 typedef int32_t t7;
101 typedef int64_t t8;
102 typedef struct { uint8_t bytes[16]; } t9;
103 typedef struct { uint16_t words[16]; } t10;
104 typedef struct { uint32_t words[16]; } t11;
105 typedef struct { uint64_t words[16]; } t12;
106 
107 typedef AlignedCharArrayUnion<t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11, t12> U;
108 
109 static_assert(sizeof(U) == sizeof(uint64_t[16]), "Statically-computed size must be right");
110 static_assert(alignof(U) == alignof(uint64_t), "Statically-computed alignment must be right");
111 
112 TEST(AlignOfTest, BasicAlignedArray) {
113   EXPECT_LE(1u, alignof(AlignedCharArrayUnion<A1>));
114   EXPECT_LE(2u, alignof(AlignedCharArrayUnion<A2>));
115   EXPECT_LE(4u, alignof(AlignedCharArrayUnion<A4>));
116   EXPECT_LE(8u, alignof(AlignedCharArrayUnion<A8>));
117 
118   EXPECT_LE(1u, sizeof(AlignedCharArrayUnion<A1>));
119   EXPECT_LE(2u, sizeof(AlignedCharArrayUnion<A2>));
120   EXPECT_LE(4u, sizeof(AlignedCharArrayUnion<A4>));
121   EXPECT_LE(8u, sizeof(AlignedCharArrayUnion<A8>));
122 
123   EXPECT_EQ(1u, (alignof(AlignedCharArrayUnion<A1>)));
124   EXPECT_EQ(2u, (alignof(AlignedCharArrayUnion<A1, A2>)));
125   EXPECT_EQ(4u, (alignof(AlignedCharArrayUnion<A1, A2, A4>)));
126   EXPECT_EQ(8u, (alignof(AlignedCharArrayUnion<A1, A2, A4, A8>)));
127 
128   EXPECT_EQ(1u, sizeof(AlignedCharArrayUnion<A1>));
129   EXPECT_EQ(2u, sizeof(AlignedCharArrayUnion<A1, A2>));
130   EXPECT_EQ(4u, sizeof(AlignedCharArrayUnion<A1, A2, A4>));
131   EXPECT_EQ(8u, sizeof(AlignedCharArrayUnion<A1, A2, A4, A8>));
132 
133   EXPECT_EQ(1u, (alignof(AlignedCharArrayUnion<A1[1]>)));
134   EXPECT_EQ(2u, (alignof(AlignedCharArrayUnion<A1[2], A2[1]>)));
135   EXPECT_EQ(4u, (alignof(AlignedCharArrayUnion<A1[42], A2[55], A4[13]>)));
136   EXPECT_EQ(8u, (alignof(AlignedCharArrayUnion<A1[2], A2[1], A4, A8>)));
137 
138   EXPECT_EQ(1u,  sizeof(AlignedCharArrayUnion<A1[1]>));
139   EXPECT_EQ(2u,  sizeof(AlignedCharArrayUnion<A1[2], A2[1]>));
140   EXPECT_EQ(4u,  sizeof(AlignedCharArrayUnion<A1[3], A2[2], A4>));
141   EXPECT_EQ(16u, sizeof(AlignedCharArrayUnion<A1, A2[3],
142                                               A4[3], A8>));
143 
144   // For other tests we simply assert that the alignment of the union mathes
145   // that of the fundamental type and hope that we have any weird type
146   // productions that would trigger bugs.
147   EXPECT_EQ(alignof(T<char>), alignof(AlignedCharArrayUnion<char>));
148   EXPECT_EQ(alignof(T<short>), alignof(AlignedCharArrayUnion<short>));
149   EXPECT_EQ(alignof(T<int>), alignof(AlignedCharArrayUnion<int>));
150   EXPECT_EQ(alignof(T<long>), alignof(AlignedCharArrayUnion<long>));
151   EXPECT_EQ(alignof(T<long long>), alignof(AlignedCharArrayUnion<long long>));
152   EXPECT_EQ(alignof(T<float>), alignof(AlignedCharArrayUnion<float>));
153   EXPECT_EQ(alignof(T<double>), alignof(AlignedCharArrayUnion<double>));
154   EXPECT_EQ(alignof(T<long double>),
155             alignof(AlignedCharArrayUnion<long double>));
156   EXPECT_EQ(alignof(T<void *>), alignof(AlignedCharArrayUnion<void *>));
157   EXPECT_EQ(alignof(T<int *>), alignof(AlignedCharArrayUnion<int *>));
158   EXPECT_EQ(alignof(T<double (*)(double)>),
159             alignof(AlignedCharArrayUnion<double (*)(double)>));
160   EXPECT_EQ(alignof(T<double (S6::*)()>),
161             alignof(AlignedCharArrayUnion<double (S6::*)()>));
162   EXPECT_EQ(alignof(S1), alignof(AlignedCharArrayUnion<S1>));
163   EXPECT_EQ(alignof(S2), alignof(AlignedCharArrayUnion<S2>));
164   EXPECT_EQ(alignof(S3), alignof(AlignedCharArrayUnion<S3>));
165   EXPECT_EQ(alignof(S4), alignof(AlignedCharArrayUnion<S4>));
166   EXPECT_EQ(alignof(S5), alignof(AlignedCharArrayUnion<S5>));
167   EXPECT_EQ(alignof(S6), alignof(AlignedCharArrayUnion<S6>));
168   EXPECT_EQ(alignof(D1), alignof(AlignedCharArrayUnion<D1>));
169   EXPECT_EQ(alignof(D2), alignof(AlignedCharArrayUnion<D2>));
170   EXPECT_EQ(alignof(D3), alignof(AlignedCharArrayUnion<D3>));
171   EXPECT_EQ(alignof(D4), alignof(AlignedCharArrayUnion<D4>));
172   EXPECT_EQ(alignof(D5), alignof(AlignedCharArrayUnion<D5>));
173   EXPECT_EQ(alignof(D6), alignof(AlignedCharArrayUnion<D6>));
174   EXPECT_EQ(alignof(D7), alignof(AlignedCharArrayUnion<D7>));
175   EXPECT_EQ(alignof(D8), alignof(AlignedCharArrayUnion<D8>));
176   EXPECT_EQ(alignof(D9), alignof(AlignedCharArrayUnion<D9>));
177   EXPECT_EQ(alignof(V1), alignof(AlignedCharArrayUnion<V1>));
178   EXPECT_EQ(alignof(V2), alignof(AlignedCharArrayUnion<V2>));
179   EXPECT_EQ(alignof(V3), alignof(AlignedCharArrayUnion<V3>));
180   EXPECT_EQ(alignof(V4), alignof(AlignedCharArrayUnion<V4>));
181   EXPECT_EQ(alignof(V5), alignof(AlignedCharArrayUnion<V5>));
182   EXPECT_EQ(alignof(V6), alignof(AlignedCharArrayUnion<V6>));
183   EXPECT_EQ(alignof(V7), alignof(AlignedCharArrayUnion<V7>));
184 
185   // Some versions of MSVC get this wrong somewhat disturbingly. The failure
186   // appears to be benign: alignof(V8) produces a preposterous value: 12
187 #ifndef _MSC_VER
188   EXPECT_EQ(alignof(V8), alignof(AlignedCharArrayUnion<V8>));
189 #endif
190 
191   EXPECT_EQ(sizeof(char), sizeof(AlignedCharArrayUnion<char>));
192   EXPECT_EQ(sizeof(char[1]), sizeof(AlignedCharArrayUnion<char[1]>));
193   EXPECT_EQ(sizeof(char[2]), sizeof(AlignedCharArrayUnion<char[2]>));
194   EXPECT_EQ(sizeof(char[3]), sizeof(AlignedCharArrayUnion<char[3]>));
195   EXPECT_EQ(sizeof(char[4]), sizeof(AlignedCharArrayUnion<char[4]>));
196   EXPECT_EQ(sizeof(char[5]), sizeof(AlignedCharArrayUnion<char[5]>));
197   EXPECT_EQ(sizeof(char[8]), sizeof(AlignedCharArrayUnion<char[8]>));
198   EXPECT_EQ(sizeof(char[13]), sizeof(AlignedCharArrayUnion<char[13]>));
199   EXPECT_EQ(sizeof(char[16]), sizeof(AlignedCharArrayUnion<char[16]>));
200   EXPECT_EQ(sizeof(char[21]), sizeof(AlignedCharArrayUnion<char[21]>));
201   EXPECT_EQ(sizeof(char[32]), sizeof(AlignedCharArrayUnion<char[32]>));
202   EXPECT_EQ(sizeof(short), sizeof(AlignedCharArrayUnion<short>));
203   EXPECT_EQ(sizeof(int), sizeof(AlignedCharArrayUnion<int>));
204   EXPECT_EQ(sizeof(long), sizeof(AlignedCharArrayUnion<long>));
205   EXPECT_EQ(sizeof(long long),
206             sizeof(AlignedCharArrayUnion<long long>));
207   EXPECT_EQ(sizeof(float), sizeof(AlignedCharArrayUnion<float>));
208   EXPECT_EQ(sizeof(double), sizeof(AlignedCharArrayUnion<double>));
209   EXPECT_EQ(sizeof(long double),
210             sizeof(AlignedCharArrayUnion<long double>));
211   EXPECT_EQ(sizeof(void *), sizeof(AlignedCharArrayUnion<void *>));
212   EXPECT_EQ(sizeof(int *), sizeof(AlignedCharArrayUnion<int *>));
213   EXPECT_EQ(sizeof(double (*)(double)),
214             sizeof(AlignedCharArrayUnion<double (*)(double)>));
215   EXPECT_EQ(sizeof(double (S6::*)()),
216             sizeof(AlignedCharArrayUnion<double (S6::*)()>));
217   EXPECT_EQ(sizeof(S1), sizeof(AlignedCharArrayUnion<S1>));
218   EXPECT_EQ(sizeof(S2), sizeof(AlignedCharArrayUnion<S2>));
219   EXPECT_EQ(sizeof(S3), sizeof(AlignedCharArrayUnion<S3>));
220   EXPECT_EQ(sizeof(S4), sizeof(AlignedCharArrayUnion<S4>));
221   EXPECT_EQ(sizeof(S5), sizeof(AlignedCharArrayUnion<S5>));
222   EXPECT_EQ(sizeof(S6), sizeof(AlignedCharArrayUnion<S6>));
223   EXPECT_EQ(sizeof(D1), sizeof(AlignedCharArrayUnion<D1>));
224   EXPECT_EQ(sizeof(D2), sizeof(AlignedCharArrayUnion<D2>));
225   EXPECT_EQ(sizeof(D3), sizeof(AlignedCharArrayUnion<D3>));
226   EXPECT_EQ(sizeof(D4), sizeof(AlignedCharArrayUnion<D4>));
227   EXPECT_EQ(sizeof(D5), sizeof(AlignedCharArrayUnion<D5>));
228   EXPECT_EQ(sizeof(D6), sizeof(AlignedCharArrayUnion<D6>));
229   EXPECT_EQ(sizeof(D7), sizeof(AlignedCharArrayUnion<D7>));
230   EXPECT_EQ(sizeof(D8), sizeof(AlignedCharArrayUnion<D8>));
231   EXPECT_EQ(sizeof(D9), sizeof(AlignedCharArrayUnion<D9>));
232   EXPECT_EQ(sizeof(D9[1]), sizeof(AlignedCharArrayUnion<D9[1]>));
233   EXPECT_EQ(sizeof(D9[2]), sizeof(AlignedCharArrayUnion<D9[2]>));
234   EXPECT_EQ(sizeof(D9[3]), sizeof(AlignedCharArrayUnion<D9[3]>));
235   EXPECT_EQ(sizeof(D9[4]), sizeof(AlignedCharArrayUnion<D9[4]>));
236   EXPECT_EQ(sizeof(D9[5]), sizeof(AlignedCharArrayUnion<D9[5]>));
237   EXPECT_EQ(sizeof(D9[8]), sizeof(AlignedCharArrayUnion<D9[8]>));
238   EXPECT_EQ(sizeof(D9[13]), sizeof(AlignedCharArrayUnion<D9[13]>));
239   EXPECT_EQ(sizeof(D9[16]), sizeof(AlignedCharArrayUnion<D9[16]>));
240   EXPECT_EQ(sizeof(D9[21]), sizeof(AlignedCharArrayUnion<D9[21]>));
241   EXPECT_EQ(sizeof(D9[32]), sizeof(AlignedCharArrayUnion<D9[32]>));
242   EXPECT_EQ(sizeof(V1), sizeof(AlignedCharArrayUnion<V1>));
243   EXPECT_EQ(sizeof(V2), sizeof(AlignedCharArrayUnion<V2>));
244   EXPECT_EQ(sizeof(V3), sizeof(AlignedCharArrayUnion<V3>));
245   EXPECT_EQ(sizeof(V4), sizeof(AlignedCharArrayUnion<V4>));
246   EXPECT_EQ(sizeof(V5), sizeof(AlignedCharArrayUnion<V5>));
247   EXPECT_EQ(sizeof(V6), sizeof(AlignedCharArrayUnion<V6>));
248   EXPECT_EQ(sizeof(V7), sizeof(AlignedCharArrayUnion<V7>));
249 
250   // Some versions of MSVC also get this wrong. The failure again appears to be
251   // benign: sizeof(V8) is only 52 bytes, but our array reserves 56.
252 #ifndef _MSC_VER
253   EXPECT_EQ(sizeof(V8), sizeof(AlignedCharArrayUnion<V8>));
254 #endif
255 
256   EXPECT_EQ(1u, (alignof(AlignedCharArray<1, 1>)));
257   EXPECT_EQ(2u, (alignof(AlignedCharArray<2, 1>)));
258   EXPECT_EQ(4u, (alignof(AlignedCharArray<4, 1>)));
259   EXPECT_EQ(8u, (alignof(AlignedCharArray<8, 1>)));
260   EXPECT_EQ(16u, (alignof(AlignedCharArray<16, 1>)));
261 
262   EXPECT_EQ(1u, sizeof(AlignedCharArray<1, 1>));
263   EXPECT_EQ(7u, sizeof(AlignedCharArray<1, 7>));
264   EXPECT_EQ(2u, sizeof(AlignedCharArray<2, 2>));
265   EXPECT_EQ(16u, sizeof(AlignedCharArray<2, 16>));
266 }
267 } // end anonymous namespace
268