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 #include "llvm/Support/AlignOf.h" 11 #include "llvm/Support/Compiler.h" 12 13 #include "gtest/gtest.h" 14 15 using namespace llvm; 16 17 namespace { 18 19 // Disable warnings about questionable type definitions. 20 // We're testing that even questionable types work with the alignment utilities. 21 #ifdef _MSC_VER 22 #pragma warning(disable:4584) 23 #endif 24 25 // Define some fixed alignment types to use in these tests. 26 #if __cplusplus == 201103L || __has_feature(cxx_alignas) 27 typedef char alignas(1) A1; 28 typedef char alignas(2) A2; 29 typedef char alignas(4) A4; 30 typedef char alignas(8) A8; 31 #elif defined(__clang__) || defined(__GNUC__) 32 typedef char A1 __attribute__((aligned(1))); 33 typedef char A2 __attribute__((aligned(2))); 34 typedef char A4 __attribute__((aligned(4))); 35 typedef char A8 __attribute__((aligned(8))); 36 #elif defined(_MSC_VER) 37 typedef __declspec(align(1)) char A1; 38 typedef __declspec(align(2)) char A2; 39 typedef __declspec(align(4)) char A4; 40 typedef __declspec(align(8)) char A8; 41 #else 42 # error No supported align as directive. 43 #endif 44 45 // Wrap the forced aligned types in structs to hack around compiler bugs. 46 struct SA1 { A1 a; }; 47 struct SA2 { A2 a; }; 48 struct SA4 { A4 a; }; 49 struct SA8 { A8 a; }; 50 51 struct S1 {}; 52 struct S2 { char a; }; 53 struct S3 { int x; }; 54 struct S4 { double y; }; 55 struct S5 { A1 a1; A2 a2; A4 a4; A8 a8; }; 56 struct S6 { double f(); }; 57 struct D1 : S1 {}; 58 struct D2 : S6 { float g(); }; 59 struct D3 : S2 {}; 60 struct D4 : S2 { int x; }; 61 struct D5 : S3 { char c; }; 62 struct D6 : S2, S3 {}; 63 struct D7 : S1, S3 {}; 64 struct D8 : S1, D4, D5 { double x[2]; }; 65 struct D9 : S1, D1 { S1 s1; }; 66 struct V1 { virtual ~V1(); }; 67 struct V2 { int x; virtual ~V2(); }; 68 struct V3 : V1 { virtual ~V3(); }; 69 struct V4 : virtual V2 { int y; virtual ~V4(); }; 70 struct V5 : V4, V3 { double z; virtual ~V5(); }; 71 struct V6 : S1 { virtual ~V6(); }; 72 struct V7 : virtual V2, virtual V6 { virtual ~V7(); }; 73 struct V8 : V5, virtual V6, V7 { double zz; virtual ~V8(); }; 74 75 // Ensure alignment is a compile-time constant. 76 char LLVM_ATTRIBUTE_UNUSED test_arr1 77 [AlignOf<char>::Alignment > 0] 78 [AlignOf<short>::Alignment > 0] 79 [AlignOf<int>::Alignment > 0] 80 [AlignOf<long>::Alignment > 0] 81 [AlignOf<long long>::Alignment > 0] 82 [AlignOf<float>::Alignment > 0] 83 [AlignOf<double>::Alignment > 0] 84 [AlignOf<long double>::Alignment > 0] 85 [AlignOf<void *>::Alignment > 0] 86 [AlignOf<int *>::Alignment > 0] 87 [AlignOf<double (*)(double)>::Alignment > 0] 88 [AlignOf<double (S6::*)()>::Alignment > 0]; 89 char LLVM_ATTRIBUTE_UNUSED test_arr2 90 [AlignOf<A1>::Alignment > 0] 91 [AlignOf<A2>::Alignment > 0] 92 [AlignOf<A4>::Alignment > 0] 93 [AlignOf<A8>::Alignment > 0] 94 [AlignOf<SA1>::Alignment > 0] 95 [AlignOf<SA2>::Alignment > 0] 96 [AlignOf<SA4>::Alignment > 0] 97 [AlignOf<SA8>::Alignment > 0]; 98 char LLVM_ATTRIBUTE_UNUSED test_arr3 99 [AlignOf<S1>::Alignment > 0] 100 [AlignOf<S2>::Alignment > 0] 101 [AlignOf<S3>::Alignment > 0] 102 [AlignOf<S4>::Alignment > 0] 103 [AlignOf<S5>::Alignment > 0] 104 [AlignOf<S6>::Alignment > 0]; 105 char LLVM_ATTRIBUTE_UNUSED test_arr4 106 [AlignOf<D1>::Alignment > 0] 107 [AlignOf<D2>::Alignment > 0] 108 [AlignOf<D3>::Alignment > 0] 109 [AlignOf<D4>::Alignment > 0] 110 [AlignOf<D5>::Alignment > 0] 111 [AlignOf<D6>::Alignment > 0] 112 [AlignOf<D7>::Alignment > 0] 113 [AlignOf<D8>::Alignment > 0] 114 [AlignOf<D9>::Alignment > 0]; 115 char LLVM_ATTRIBUTE_UNUSED test_arr5 116 [AlignOf<V1>::Alignment > 0] 117 [AlignOf<V2>::Alignment > 0] 118 [AlignOf<V3>::Alignment > 0] 119 [AlignOf<V4>::Alignment > 0] 120 [AlignOf<V5>::Alignment > 0] 121 [AlignOf<V6>::Alignment > 0] 122 [AlignOf<V7>::Alignment > 0] 123 [AlignOf<V8>::Alignment > 0]; 124 125 TEST(AlignOfTest, BasicAlignmentInvariants) { 126 // For a very strange reason, many compilers do not support this. Both Clang 127 // and GCC fail to align these properly. 128 EXPECT_EQ(1u, alignOf<A1>()); 129 #if 0 130 EXPECT_EQ(2u, alignOf<A2>()); 131 EXPECT_EQ(4u, alignOf<A4>()); 132 EXPECT_EQ(8u, alignOf<A8>()); 133 #endif 134 135 // But once wrapped in structs, the alignment is correctly managed. 136 EXPECT_LE(1u, alignOf<SA1>()); 137 EXPECT_LE(2u, alignOf<SA2>()); 138 EXPECT_LE(4u, alignOf<SA4>()); 139 EXPECT_LE(8u, alignOf<SA8>()); 140 141 EXPECT_EQ(1u, alignOf<char>()); 142 EXPECT_LE(alignOf<char>(), alignOf<short>()); 143 EXPECT_LE(alignOf<short>(), alignOf<int>()); 144 EXPECT_LE(alignOf<int>(), alignOf<long>()); 145 EXPECT_LE(alignOf<long>(), alignOf<long long>()); 146 EXPECT_LE(alignOf<char>(), alignOf<float>()); 147 EXPECT_LE(alignOf<float>(), alignOf<double>()); 148 EXPECT_LE(alignOf<char>(), alignOf<long double>()); 149 EXPECT_LE(alignOf<char>(), alignOf<void *>()); 150 EXPECT_EQ(alignOf<void *>(), alignOf<int *>()); 151 EXPECT_LE(alignOf<char>(), alignOf<S1>()); 152 EXPECT_LE(alignOf<S1>(), alignOf<S2>()); 153 EXPECT_LE(alignOf<S1>(), alignOf<S3>()); 154 EXPECT_LE(alignOf<S1>(), alignOf<S4>()); 155 EXPECT_LE(alignOf<S1>(), alignOf<S5>()); 156 EXPECT_LE(alignOf<S1>(), alignOf<S6>()); 157 EXPECT_LE(alignOf<S1>(), alignOf<D1>()); 158 EXPECT_LE(alignOf<S1>(), alignOf<D2>()); 159 EXPECT_LE(alignOf<S1>(), alignOf<D3>()); 160 EXPECT_LE(alignOf<S1>(), alignOf<D4>()); 161 EXPECT_LE(alignOf<S1>(), alignOf<D5>()); 162 EXPECT_LE(alignOf<S1>(), alignOf<D6>()); 163 EXPECT_LE(alignOf<S1>(), alignOf<D7>()); 164 EXPECT_LE(alignOf<S1>(), alignOf<D8>()); 165 EXPECT_LE(alignOf<S1>(), alignOf<D9>()); 166 EXPECT_LE(alignOf<S1>(), alignOf<V1>()); 167 EXPECT_LE(alignOf<V1>(), alignOf<V2>()); 168 EXPECT_LE(alignOf<V1>(), alignOf<V3>()); 169 EXPECT_LE(alignOf<V1>(), alignOf<V4>()); 170 EXPECT_LE(alignOf<V1>(), alignOf<V5>()); 171 EXPECT_LE(alignOf<V1>(), alignOf<V6>()); 172 EXPECT_LE(alignOf<V1>(), alignOf<V7>()); 173 EXPECT_LE(alignOf<V1>(), alignOf<V8>()); 174 } 175 176 TEST(AlignOfTest, BasicAlignedArray) { 177 // Note: this code exclusively uses the struct-wrapped arbitrarily aligned 178 // types because of the bugs mentioned above where GCC and Clang both 179 // disregard the arbitrary alignment specifier until the type is used to 180 // declare a member of a struct. 181 EXPECT_LE(1u, alignOf<AlignedCharArrayUnion<SA1> >()); 182 EXPECT_LE(2u, alignOf<AlignedCharArrayUnion<SA2> >()); 183 EXPECT_LE(4u, alignOf<AlignedCharArrayUnion<SA4> >()); 184 EXPECT_LE(8u, alignOf<AlignedCharArrayUnion<SA8> >()); 185 186 EXPECT_LE(1u, sizeof(AlignedCharArrayUnion<SA1>)); 187 EXPECT_LE(2u, sizeof(AlignedCharArrayUnion<SA2>)); 188 EXPECT_LE(4u, sizeof(AlignedCharArrayUnion<SA4>)); 189 EXPECT_LE(8u, sizeof(AlignedCharArrayUnion<SA8>)); 190 191 EXPECT_EQ(1u, (alignOf<AlignedCharArrayUnion<SA1> >())); 192 EXPECT_EQ(2u, (alignOf<AlignedCharArrayUnion<SA1, SA2> >())); 193 EXPECT_EQ(4u, (alignOf<AlignedCharArrayUnion<SA1, SA2, SA4> >())); 194 EXPECT_EQ(8u, (alignOf<AlignedCharArrayUnion<SA1, SA2, SA4, SA8> >())); 195 196 EXPECT_EQ(1u, sizeof(AlignedCharArrayUnion<SA1>)); 197 EXPECT_EQ(2u, sizeof(AlignedCharArrayUnion<SA1, SA2>)); 198 EXPECT_EQ(4u, sizeof(AlignedCharArrayUnion<SA1, SA2, SA4>)); 199 EXPECT_EQ(8u, sizeof(AlignedCharArrayUnion<SA1, SA2, SA4, SA8>)); 200 201 EXPECT_EQ(1u, (alignOf<AlignedCharArrayUnion<SA1[1]> >())); 202 EXPECT_EQ(2u, (alignOf<AlignedCharArrayUnion<SA1[2], SA2[1]> >())); 203 EXPECT_EQ(4u, (alignOf<AlignedCharArrayUnion<SA1[42], SA2[55], 204 SA4[13]> >())); 205 EXPECT_EQ(8u, (alignOf<AlignedCharArrayUnion<SA1[2], SA2[1], 206 SA4, SA8> >())); 207 208 EXPECT_EQ(1u, sizeof(AlignedCharArrayUnion<SA1[1]>)); 209 EXPECT_EQ(2u, sizeof(AlignedCharArrayUnion<SA1[2], SA2[1]>)); 210 EXPECT_EQ(4u, sizeof(AlignedCharArrayUnion<SA1[3], SA2[2], SA4>)); 211 EXPECT_EQ(16u, sizeof(AlignedCharArrayUnion<SA1, SA2[3], 212 SA4[3], SA8>)); 213 214 // For other tests we simply assert that the alignment of the union mathes 215 // that of the fundamental type and hope that we have any weird type 216 // productions that would trigger bugs. 217 EXPECT_EQ(alignOf<char>(), alignOf<AlignedCharArrayUnion<char> >()); 218 EXPECT_EQ(alignOf<short>(), alignOf<AlignedCharArrayUnion<short> >()); 219 EXPECT_EQ(alignOf<int>(), alignOf<AlignedCharArrayUnion<int> >()); 220 EXPECT_EQ(alignOf<long>(), alignOf<AlignedCharArrayUnion<long> >()); 221 EXPECT_EQ(alignOf<long long>(), 222 alignOf<AlignedCharArrayUnion<long long> >()); 223 EXPECT_EQ(alignOf<float>(), alignOf<AlignedCharArrayUnion<float> >()); 224 EXPECT_EQ(alignOf<double>(), alignOf<AlignedCharArrayUnion<double> >()); 225 EXPECT_EQ(alignOf<long double>(), 226 alignOf<AlignedCharArrayUnion<long double> >()); 227 EXPECT_EQ(alignOf<void *>(), alignOf<AlignedCharArrayUnion<void *> >()); 228 EXPECT_EQ(alignOf<int *>(), alignOf<AlignedCharArrayUnion<int *> >()); 229 EXPECT_EQ(alignOf<double (*)(double)>(), 230 alignOf<AlignedCharArrayUnion<double (*)(double)> >()); 231 EXPECT_EQ(alignOf<double (S6::*)()>(), 232 alignOf<AlignedCharArrayUnion<double (S6::*)()> >()); 233 EXPECT_EQ(alignOf<S1>(), alignOf<AlignedCharArrayUnion<S1> >()); 234 EXPECT_EQ(alignOf<S2>(), alignOf<AlignedCharArrayUnion<S2> >()); 235 EXPECT_EQ(alignOf<S3>(), alignOf<AlignedCharArrayUnion<S3> >()); 236 EXPECT_EQ(alignOf<S4>(), alignOf<AlignedCharArrayUnion<S4> >()); 237 EXPECT_EQ(alignOf<S5>(), alignOf<AlignedCharArrayUnion<S5> >()); 238 EXPECT_EQ(alignOf<S6>(), alignOf<AlignedCharArrayUnion<S6> >()); 239 EXPECT_EQ(alignOf<D1>(), alignOf<AlignedCharArrayUnion<D1> >()); 240 EXPECT_EQ(alignOf<D2>(), alignOf<AlignedCharArrayUnion<D2> >()); 241 EXPECT_EQ(alignOf<D3>(), alignOf<AlignedCharArrayUnion<D3> >()); 242 EXPECT_EQ(alignOf<D4>(), alignOf<AlignedCharArrayUnion<D4> >()); 243 EXPECT_EQ(alignOf<D5>(), alignOf<AlignedCharArrayUnion<D5> >()); 244 EXPECT_EQ(alignOf<D6>(), alignOf<AlignedCharArrayUnion<D6> >()); 245 EXPECT_EQ(alignOf<D7>(), alignOf<AlignedCharArrayUnion<D7> >()); 246 EXPECT_EQ(alignOf<D8>(), alignOf<AlignedCharArrayUnion<D8> >()); 247 EXPECT_EQ(alignOf<D9>(), alignOf<AlignedCharArrayUnion<D9> >()); 248 EXPECT_EQ(alignOf<V1>(), alignOf<AlignedCharArrayUnion<V1> >()); 249 EXPECT_EQ(alignOf<V2>(), alignOf<AlignedCharArrayUnion<V2> >()); 250 EXPECT_EQ(alignOf<V3>(), alignOf<AlignedCharArrayUnion<V3> >()); 251 EXPECT_EQ(alignOf<V4>(), alignOf<AlignedCharArrayUnion<V4> >()); 252 EXPECT_EQ(alignOf<V5>(), alignOf<AlignedCharArrayUnion<V5> >()); 253 EXPECT_EQ(alignOf<V6>(), alignOf<AlignedCharArrayUnion<V6> >()); 254 EXPECT_EQ(alignOf<V7>(), alignOf<AlignedCharArrayUnion<V7> >()); 255 256 // Some versions of MSVC get this wrong somewhat disturbingly. The failure 257 // appears to be benign: alignOf<V8>() produces a preposterous value: 12 258 #ifndef _MSC_VER 259 EXPECT_EQ(alignOf<V8>(), alignOf<AlignedCharArrayUnion<V8> >()); 260 #endif 261 262 EXPECT_EQ(sizeof(char), sizeof(AlignedCharArrayUnion<char>)); 263 EXPECT_EQ(sizeof(char[1]), sizeof(AlignedCharArrayUnion<char[1]>)); 264 EXPECT_EQ(sizeof(char[2]), sizeof(AlignedCharArrayUnion<char[2]>)); 265 EXPECT_EQ(sizeof(char[3]), sizeof(AlignedCharArrayUnion<char[3]>)); 266 EXPECT_EQ(sizeof(char[4]), sizeof(AlignedCharArrayUnion<char[4]>)); 267 EXPECT_EQ(sizeof(char[5]), sizeof(AlignedCharArrayUnion<char[5]>)); 268 EXPECT_EQ(sizeof(char[8]), sizeof(AlignedCharArrayUnion<char[8]>)); 269 EXPECT_EQ(sizeof(char[13]), sizeof(AlignedCharArrayUnion<char[13]>)); 270 EXPECT_EQ(sizeof(char[16]), sizeof(AlignedCharArrayUnion<char[16]>)); 271 EXPECT_EQ(sizeof(char[21]), sizeof(AlignedCharArrayUnion<char[21]>)); 272 EXPECT_EQ(sizeof(char[32]), sizeof(AlignedCharArrayUnion<char[32]>)); 273 EXPECT_EQ(sizeof(short), sizeof(AlignedCharArrayUnion<short>)); 274 EXPECT_EQ(sizeof(int), sizeof(AlignedCharArrayUnion<int>)); 275 EXPECT_EQ(sizeof(long), sizeof(AlignedCharArrayUnion<long>)); 276 EXPECT_EQ(sizeof(long long), 277 sizeof(AlignedCharArrayUnion<long long>)); 278 EXPECT_EQ(sizeof(float), sizeof(AlignedCharArrayUnion<float>)); 279 EXPECT_EQ(sizeof(double), sizeof(AlignedCharArrayUnion<double>)); 280 EXPECT_EQ(sizeof(long double), 281 sizeof(AlignedCharArrayUnion<long double>)); 282 EXPECT_EQ(sizeof(void *), sizeof(AlignedCharArrayUnion<void *>)); 283 EXPECT_EQ(sizeof(int *), sizeof(AlignedCharArrayUnion<int *>)); 284 EXPECT_EQ(sizeof(double (*)(double)), 285 sizeof(AlignedCharArrayUnion<double (*)(double)>)); 286 EXPECT_EQ(sizeof(double (S6::*)()), 287 sizeof(AlignedCharArrayUnion<double (S6::*)()>)); 288 EXPECT_EQ(sizeof(S1), sizeof(AlignedCharArrayUnion<S1>)); 289 EXPECT_EQ(sizeof(S2), sizeof(AlignedCharArrayUnion<S2>)); 290 EXPECT_EQ(sizeof(S3), sizeof(AlignedCharArrayUnion<S3>)); 291 EXPECT_EQ(sizeof(S4), sizeof(AlignedCharArrayUnion<S4>)); 292 EXPECT_EQ(sizeof(S5), sizeof(AlignedCharArrayUnion<S5>)); 293 EXPECT_EQ(sizeof(S6), sizeof(AlignedCharArrayUnion<S6>)); 294 EXPECT_EQ(sizeof(D1), sizeof(AlignedCharArrayUnion<D1>)); 295 EXPECT_EQ(sizeof(D2), sizeof(AlignedCharArrayUnion<D2>)); 296 EXPECT_EQ(sizeof(D3), sizeof(AlignedCharArrayUnion<D3>)); 297 EXPECT_EQ(sizeof(D4), sizeof(AlignedCharArrayUnion<D4>)); 298 EXPECT_EQ(sizeof(D5), sizeof(AlignedCharArrayUnion<D5>)); 299 EXPECT_EQ(sizeof(D6), sizeof(AlignedCharArrayUnion<D6>)); 300 EXPECT_EQ(sizeof(D7), sizeof(AlignedCharArrayUnion<D7>)); 301 EXPECT_EQ(sizeof(D8), sizeof(AlignedCharArrayUnion<D8>)); 302 EXPECT_EQ(sizeof(D9), sizeof(AlignedCharArrayUnion<D9>)); 303 EXPECT_EQ(sizeof(D9[1]), sizeof(AlignedCharArrayUnion<D9[1]>)); 304 EXPECT_EQ(sizeof(D9[2]), sizeof(AlignedCharArrayUnion<D9[2]>)); 305 EXPECT_EQ(sizeof(D9[3]), sizeof(AlignedCharArrayUnion<D9[3]>)); 306 EXPECT_EQ(sizeof(D9[4]), sizeof(AlignedCharArrayUnion<D9[4]>)); 307 EXPECT_EQ(sizeof(D9[5]), sizeof(AlignedCharArrayUnion<D9[5]>)); 308 EXPECT_EQ(sizeof(D9[8]), sizeof(AlignedCharArrayUnion<D9[8]>)); 309 EXPECT_EQ(sizeof(D9[13]), sizeof(AlignedCharArrayUnion<D9[13]>)); 310 EXPECT_EQ(sizeof(D9[16]), sizeof(AlignedCharArrayUnion<D9[16]>)); 311 EXPECT_EQ(sizeof(D9[21]), sizeof(AlignedCharArrayUnion<D9[21]>)); 312 EXPECT_EQ(sizeof(D9[32]), sizeof(AlignedCharArrayUnion<D9[32]>)); 313 EXPECT_EQ(sizeof(V1), sizeof(AlignedCharArrayUnion<V1>)); 314 EXPECT_EQ(sizeof(V2), sizeof(AlignedCharArrayUnion<V2>)); 315 EXPECT_EQ(sizeof(V3), sizeof(AlignedCharArrayUnion<V3>)); 316 EXPECT_EQ(sizeof(V4), sizeof(AlignedCharArrayUnion<V4>)); 317 EXPECT_EQ(sizeof(V5), sizeof(AlignedCharArrayUnion<V5>)); 318 EXPECT_EQ(sizeof(V6), sizeof(AlignedCharArrayUnion<V6>)); 319 EXPECT_EQ(sizeof(V7), sizeof(AlignedCharArrayUnion<V7>)); 320 321 // Some versions of MSVC also get this wrong. The failure again appears to be 322 // benign: sizeof(V8) is only 52 bytes, but our array reserves 56. 323 #ifndef _MSC_VER 324 EXPECT_EQ(sizeof(V8), sizeof(AlignedCharArrayUnion<V8>)); 325 #endif 326 } 327 328 } 329