xref: /llvm-project/llvm/unittests/Support/AlignmentTest.cpp (revision 396521378f0a5c5373c0321e156de7cbcffb3cd3)
1 //=== - llvm/unittest/Support/Alignment.cpp - Alignment utility tests -----===//
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/Alignment.h"
10 #include "gtest/gtest.h"
11 
12 #include <vector>
13 
14 using namespace llvm;
15 
16 namespace {
17 
18 std::vector<uint64_t> getValidAlignments() {
19   std::vector<uint64_t> Out;
20   for (size_t Shift = 0; Shift < 64; ++Shift)
21     Out.push_back(1ULL << Shift);
22   return Out;
23 }
24 
25 TEST(AlignmentTest, AlignDefaultCTor) { EXPECT_EQ(Align().value(), 1ULL); }
26 
27 TEST(AlignmentTest, MaybeAlignDefaultCTor) {
28   EXPECT_FALSE(MaybeAlign().hasValue());
29 }
30 
31 TEST(AlignmentTest, ValidCTors) {
32   for (uint64_t Value : getValidAlignments()) {
33     EXPECT_EQ(Align(Value).value(), Value);
34     EXPECT_EQ((*MaybeAlign(Value)).value(), Value);
35   }
36 }
37 
38 TEST(AlignmentTest, CheckMaybeAlignHasValue) {
39   EXPECT_TRUE(MaybeAlign(1));
40   EXPECT_TRUE(MaybeAlign(1).hasValue());
41   EXPECT_FALSE(MaybeAlign(0));
42   EXPECT_FALSE(MaybeAlign(0).hasValue());
43   EXPECT_FALSE(MaybeAlign());
44   EXPECT_FALSE(MaybeAlign().hasValue());
45 }
46 
47 TEST(AlignmentTest, Division) {
48   for (uint64_t Value : getValidAlignments()) {
49     if (Value > 1) {
50       EXPECT_EQ(Align(Value) / 2, Value / 2);
51       EXPECT_EQ(MaybeAlign(Value) / 2, Value / 2);
52     }
53   }
54   EXPECT_EQ(MaybeAlign(0) / 2, MaybeAlign(0));
55 }
56 
57 TEST(AlignmentTest, AlignTo) {
58   struct {
59     uint64_t alignment;
60     uint64_t offset;
61     uint64_t rounded;
62   } kTests[] = {
63       // MaybeAlign
64       {0, 0, 0},
65       {0, 1, 1},
66       {0, 5, 5},
67       // MaybeAlign / Align
68       {1, 0, 0},
69       {1, 1, 1},
70       {1, 5, 5},
71       {2, 0, 0},
72       {2, 1, 2},
73       {2, 2, 2},
74       {2, 7, 8},
75       {2, 16, 16},
76       {4, 0, 0},
77       {4, 1, 4},
78       {4, 4, 4},
79       {4, 6, 8},
80   };
81   for (const auto &T : kTests) {
82     MaybeAlign A(T.alignment);
83     // Test MaybeAlign
84     EXPECT_EQ(alignTo(T.offset, A), T.rounded);
85     // Test Align
86     if (A) {
87       EXPECT_EQ(alignTo(T.offset, A.getValue()), T.rounded);
88     }
89   }
90 }
91 
92 TEST(AlignmentTest, Log2) {
93   for (uint64_t Value : getValidAlignments()) {
94     EXPECT_EQ(Log2(Align(Value)), Log2_64(Value));
95     EXPECT_EQ(Log2(MaybeAlign(Value)), Log2_64(Value));
96   }
97 }
98 
99 TEST(AlignmentTest, MinAlign) {
100   struct {
101     uint64_t A;
102     uint64_t B;
103     uint64_t MinAlign;
104   } kTests[] = {
105       // MaybeAlign
106       {0, 0, 0},
107       {0, 8, 8},
108       {2, 0, 2},
109       // MaybeAlign / Align
110       {1, 2, 1},
111       {8, 4, 4},
112   };
113   for (const auto &T : kTests) {
114     EXPECT_EQ(commonAlignment(MaybeAlign(T.A), MaybeAlign(T.B)), T.MinAlign);
115     EXPECT_EQ(MinAlign(T.A, T.B), T.MinAlign);
116     if (T.A) {
117       EXPECT_EQ(commonAlignment(Align(T.A), MaybeAlign(T.B)), T.MinAlign);
118     }
119     if (T.B) {
120       EXPECT_EQ(commonAlignment(MaybeAlign(T.A), Align(T.B)), T.MinAlign);
121     }
122     if (T.A && T.B) {
123       EXPECT_EQ(commonAlignment(Align(T.A), Align(T.B)), T.MinAlign);
124     }
125   }
126 }
127 
128 TEST(AlignmentTest, Encode_Decode) {
129   for (uint64_t Value : getValidAlignments()) {
130     {
131       Align Actual(Value);
132       Align Expected = decodeMaybeAlign(encode(Actual)).getValue();
133       EXPECT_EQ(Expected, Actual);
134     }
135     {
136       MaybeAlign Actual(Value);
137       MaybeAlign Expected = decodeMaybeAlign(encode(Actual));
138       EXPECT_EQ(Expected, Actual);
139     }
140   }
141   MaybeAlign Actual(0);
142   MaybeAlign Expected = decodeMaybeAlign(encode(Actual));
143   EXPECT_EQ(Expected, Actual);
144 }
145 
146 TEST(AlignmentTest, isAligned) {
147   struct {
148     uint64_t alignment;
149     uint64_t offset;
150     bool isAligned;
151   } kTests[] = {
152       // MaybeAlign / Align
153       {1, 0, true},  {1, 1, true},  {1, 5, true},  {2, 0, true},
154       {2, 1, false}, {2, 2, true},  {2, 7, false}, {2, 16, true},
155       {4, 0, true},  {4, 1, false}, {4, 4, true},  {4, 6, false},
156   };
157   for (const auto &T : kTests) {
158     MaybeAlign A(T.alignment);
159     // Test MaybeAlign
160     EXPECT_EQ(isAligned(A, T.offset), T.isAligned);
161     // Test Align
162     if (A) {
163       EXPECT_EQ(isAligned(A.getValue(), T.offset), T.isAligned);
164     }
165   }
166 }
167 
168 TEST(AlignmentTest, AlignComparisons) {
169   std::vector<uint64_t> ValidAlignments = getValidAlignments();
170   std::sort(ValidAlignments.begin(), ValidAlignments.end());
171   for (size_t I = 1; I < ValidAlignments.size(); ++I) {
172     assert(I >= 1);
173     const Align A(ValidAlignments[I - 1]);
174     const Align B(ValidAlignments[I]);
175     EXPECT_EQ(A, A);
176     EXPECT_NE(A, B);
177     EXPECT_LT(A, B);
178     EXPECT_GT(B, A);
179     EXPECT_LE(A, B);
180     EXPECT_GE(B, A);
181     EXPECT_LE(A, A);
182     EXPECT_GE(A, A);
183 
184     EXPECT_EQ(A, A.value());
185     EXPECT_NE(A, B.value());
186     EXPECT_LT(A, B.value());
187     EXPECT_GT(B, A.value());
188     EXPECT_LE(A, B.value());
189     EXPECT_GE(B, A.value());
190     EXPECT_LE(A, A.value());
191     EXPECT_GE(A, A.value());
192 
193     EXPECT_EQ(std::max(A, B), B);
194     EXPECT_EQ(std::min(A, B), A);
195 
196     const MaybeAlign MA(ValidAlignments[I - 1]);
197     const MaybeAlign MB(ValidAlignments[I]);
198     EXPECT_EQ(MA, MA);
199     EXPECT_NE(MA, MB);
200     EXPECT_LT(MA, MB);
201     EXPECT_GT(MB, MA);
202     EXPECT_LE(MA, MB);
203     EXPECT_GE(MB, MA);
204     EXPECT_LE(MA, MA);
205     EXPECT_GE(MA, MA);
206 
207     EXPECT_EQ(MA, MA ? (*MA).value() : 0);
208     EXPECT_NE(MA, MB ? (*MB).value() : 0);
209     EXPECT_LT(MA, MB ? (*MB).value() : 0);
210     EXPECT_GT(MB, MA ? (*MA).value() : 0);
211     EXPECT_LE(MA, MB ? (*MB).value() : 0);
212     EXPECT_GE(MB, MA ? (*MA).value() : 0);
213     EXPECT_LE(MA, MA ? (*MA).value() : 0);
214     EXPECT_GE(MA, MA ? (*MA).value() : 0);
215 
216     EXPECT_EQ(std::max(A, B), B);
217     EXPECT_EQ(std::min(A, B), A);
218   }
219 }
220 
221 TEST(AlignmentTest, AssumeAligned) {
222   EXPECT_EQ(assumeAligned(0), Align(1));
223   EXPECT_EQ(assumeAligned(0), Align());
224   EXPECT_EQ(assumeAligned(1), Align(1));
225   EXPECT_EQ(assumeAligned(1), Align());
226 }
227 
228 // Death tests reply on assert which is disabled in release mode.
229 #ifndef NDEBUG
230 
231 // We use a subset of valid alignments for DEATH_TESTs as they are particularly
232 // slow.
233 std::vector<uint64_t> getValidAlignmentsForDeathTest() {
234   return {1, 1ULL << 31, 1ULL << 63};
235 }
236 
237 std::vector<uint64_t> getNonPowerOfTwo() { return {3, 10, 15}; }
238 
239 TEST(AlignmentDeathTest, Log2) {
240   EXPECT_DEATH(Log2(MaybeAlign(0)), ".* should be defined");
241 }
242 
243 TEST(AlignmentDeathTest, CantConvertUnsetMaybe) {
244   EXPECT_DEATH((MaybeAlign(0).getValue()), ".*");
245 }
246 
247 TEST(AlignmentDeathTest, Division) {
248   EXPECT_DEATH(Align(1) / 2, "Can't halve byte alignment");
249   EXPECT_DEATH(MaybeAlign(1) / 2, "Can't halve byte alignment");
250 
251   EXPECT_DEATH(Align(8) / 0, "Divisor must be positive and a power of 2");
252   EXPECT_DEATH(Align(8) / 3, "Divisor must be positive and a power of 2");
253 }
254 
255 TEST(AlignmentDeathTest, InvalidCTors) {
256   EXPECT_DEATH((Align(0)), "Value must not be 0");
257   for (uint64_t Value : getNonPowerOfTwo()) {
258     EXPECT_DEATH((Align(Value)), "Alignment is not a power of 2");
259     EXPECT_DEATH((MaybeAlign(Value)),
260                  "Alignment is neither 0 nor a power of 2");
261   }
262 }
263 
264 TEST(AlignmentDeathTest, ComparisonsWithZero) {
265   for (uint64_t Value : getValidAlignmentsForDeathTest()) {
266     EXPECT_DEATH((void)(Align(Value) == 0), ".* should be defined");
267     EXPECT_DEATH((void)(Align(Value) != 0), ".* should be defined");
268     EXPECT_DEATH((void)(Align(Value) >= 0), ".* should be defined");
269     EXPECT_DEATH((void)(Align(Value) <= 0), ".* should be defined");
270     EXPECT_DEATH((void)(Align(Value) > 0), ".* should be defined");
271     EXPECT_DEATH((void)(Align(Value) < 0), ".* should be defined");
272   }
273 }
274 
275 TEST(AlignmentDeathTest, CompareMaybeAlignToZero) {
276   for (uint64_t Value : getValidAlignmentsForDeathTest()) {
277     // MaybeAlign is allowed to be == or != 0
278     (void)(MaybeAlign(Value) == 0);
279     (void)(MaybeAlign(Value) != 0);
280     EXPECT_DEATH((void)(MaybeAlign(Value) >= 0), ".* should be defined");
281     EXPECT_DEATH((void)(MaybeAlign(Value) <= 0), ".* should be defined");
282     EXPECT_DEATH((void)(MaybeAlign(Value) > 0), ".* should be defined");
283     EXPECT_DEATH((void)(MaybeAlign(Value) < 0), ".* should be defined");
284   }
285 }
286 
287 TEST(AlignmentDeathTest, CompareAlignToUndefMaybeAlign) {
288   for (uint64_t Value : getValidAlignmentsForDeathTest()) {
289     EXPECT_DEATH((void)(Align(Value) == MaybeAlign(0)), ".* should be defined");
290     EXPECT_DEATH((void)(Align(Value) != MaybeAlign(0)), ".* should be defined");
291     EXPECT_DEATH((void)(Align(Value) >= MaybeAlign(0)), ".* should be defined");
292     EXPECT_DEATH((void)(Align(Value) <= MaybeAlign(0)), ".* should be defined");
293     EXPECT_DEATH((void)(Align(Value) > MaybeAlign(0)), ".* should be defined");
294     EXPECT_DEATH((void)(Align(Value) < MaybeAlign(0)), ".* should be defined");
295   }
296 }
297 
298 #endif // NDEBUG
299 
300 } // end anonymous namespace
301