xref: /llvm-project/llvm/unittests/Support/AlignmentTest.cpp (revision 41dfc69dc7fc21b8de9c2aac506930dc85cac70a)
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 TEST(AlignmentTest, Log2) {
92   for (uint64_t Value : getValidAlignments()) {
93     EXPECT_EQ(Log2(Align(Value)), Log2_64(Value));
94     EXPECT_EQ(Log2(MaybeAlign(Value)), Log2_64(Value));
95   }
96 }
97 
98 TEST(AlignmentTest, MinAlign) {
99   struct {
100     uint64_t A;
101     uint64_t B;
102     uint64_t MinAlign;
103   } kTests[] = {
104       // MaybeAlign
105       {0, 0, 0},
106       {0, 8, 8},
107       {2, 0, 2},
108       // MaybeAlign / Align
109       {1, 2, 1},
110       {8, 4, 4},
111   };
112   for (const auto &T : kTests) {
113     EXPECT_EQ(commonAlignment(MaybeAlign(T.A), MaybeAlign(T.B)), T.MinAlign);
114     EXPECT_EQ(MinAlign(T.A, T.B), T.MinAlign);
115     if (T.A)
116       EXPECT_EQ(commonAlignment(Align(T.A), MaybeAlign(T.B)), T.MinAlign);
117     if (T.B)
118       EXPECT_EQ(commonAlignment(MaybeAlign(T.A), Align(T.B)), T.MinAlign);
119     if (T.A && T.B)
120       EXPECT_EQ(commonAlignment(Align(T.A), Align(T.B)), T.MinAlign);
121   }
122 }
123 
124 TEST(AlignmentTest, Encode_Decode) {
125   for (uint64_t Value : getValidAlignments()) {
126     {
127       Align Actual(Value);
128       Align Expected = decodeMaybeAlign(encode(Actual)).getValue();
129       EXPECT_EQ(Expected, Actual);
130     }
131     {
132       MaybeAlign Actual(Value);
133       MaybeAlign Expected = decodeMaybeAlign(encode(Actual));
134       EXPECT_EQ(Expected, Actual);
135     }
136   }
137   MaybeAlign Actual(0);
138   MaybeAlign Expected = decodeMaybeAlign(encode(Actual));
139   EXPECT_EQ(Expected, Actual);
140 }
141 
142 TEST(AlignmentTest, isAligned) {
143   struct {
144     uint64_t alignment;
145     uint64_t offset;
146     bool isAligned;
147   } kTests[] = {
148       // MaybeAlign / Align
149       {1, 0, true},  {1, 1, true},  {1, 5, true},  {2, 0, true},
150       {2, 1, false}, {2, 2, true},  {2, 7, false}, {2, 16, true},
151       {4, 0, true},  {4, 1, false}, {4, 4, true},  {4, 6, false},
152   };
153   for (const auto &T : kTests) {
154     MaybeAlign A(T.alignment);
155     // Test MaybeAlign
156     EXPECT_EQ(isAligned(A, T.offset), T.isAligned);
157     // Test Align
158     if (A)
159       EXPECT_EQ(isAligned(A.getValue(), T.offset), T.isAligned);
160   }
161 }
162 
163 TEST(AlignmentTest, AlignComparisons) {
164   std::vector<uint64_t> ValidAlignments = getValidAlignments();
165   std::sort(ValidAlignments.begin(), ValidAlignments.end());
166   for (size_t I = 1; I < ValidAlignments.size(); ++I) {
167     assert(I >= 1);
168     const Align A(ValidAlignments[I - 1]);
169     const Align B(ValidAlignments[I]);
170     EXPECT_EQ(A, A);
171     EXPECT_NE(A, B);
172     EXPECT_LT(A, B);
173     EXPECT_GT(B, A);
174     EXPECT_LE(A, B);
175     EXPECT_GE(B, A);
176     EXPECT_LE(A, A);
177     EXPECT_GE(A, A);
178 
179     EXPECT_EQ(A, A.value());
180     EXPECT_NE(A, B.value());
181     EXPECT_LT(A, B.value());
182     EXPECT_GT(B, A.value());
183     EXPECT_LE(A, B.value());
184     EXPECT_GE(B, A.value());
185     EXPECT_LE(A, A.value());
186     EXPECT_GE(A, A.value());
187 
188     EXPECT_EQ(std::max(A, B), B);
189     EXPECT_EQ(std::min(A, B), A);
190 
191     const MaybeAlign MA(ValidAlignments[I - 1]);
192     const MaybeAlign MB(ValidAlignments[I]);
193     EXPECT_EQ(MA, MA);
194     EXPECT_NE(MA, MB);
195     EXPECT_LT(MA, MB);
196     EXPECT_GT(MB, MA);
197     EXPECT_LE(MA, MB);
198     EXPECT_GE(MB, MA);
199     EXPECT_LE(MA, MA);
200     EXPECT_GE(MA, MA);
201 
202     EXPECT_EQ(MA, MA ? (*MA).value() : 0);
203     EXPECT_NE(MA, MB ? (*MB).value() : 0);
204     EXPECT_LT(MA, MB ? (*MB).value() : 0);
205     EXPECT_GT(MB, MA ? (*MA).value() : 0);
206     EXPECT_LE(MA, MB ? (*MB).value() : 0);
207     EXPECT_GE(MB, MA ? (*MA).value() : 0);
208     EXPECT_LE(MA, MA ? (*MA).value() : 0);
209     EXPECT_GE(MA, MA ? (*MA).value() : 0);
210 
211     EXPECT_EQ(std::max(A, B), B);
212     EXPECT_EQ(std::min(A, B), A);
213   }
214 }
215 
216 TEST(AlignmentTest, AssumeAligned) {
217   EXPECT_EQ(assumeAligned(0), Align(1));
218   EXPECT_EQ(assumeAligned(0), Align());
219   EXPECT_EQ(assumeAligned(1), Align(1));
220   EXPECT_EQ(assumeAligned(1), Align());
221 }
222 
223 // Death tests reply on assert which is disabled in release mode.
224 #ifndef NDEBUG
225 
226 // We use a subset of valid alignments for DEATH_TESTs as they are particularly
227 // slow.
228 std::vector<uint64_t> getValidAlignmentsForDeathTest() {
229   return {1, 1ULL << 31, 1ULL << 63};
230 }
231 
232 std::vector<uint64_t> getNonPowerOfTwo() { return {3, 10, 15}; }
233 
234 TEST(AlignmentDeathTest, Log2) {
235   EXPECT_DEATH(Log2(MaybeAlign(0)), ".* should be defined");
236 }
237 
238 TEST(AlignmentDeathTest, CantConvertUnsetMaybe) {
239   EXPECT_DEATH((MaybeAlign(0).getValue()), ".*");
240 }
241 
242 TEST(AlignmentDeathTest, Division) {
243   EXPECT_DEATH(Align(1) / 2, "Can't halve byte alignment");
244   EXPECT_DEATH(MaybeAlign(1) / 2, "Can't halve byte alignment");
245 
246   EXPECT_DEATH(Align(8) / 0, "Divisor must be positive and a power of 2");
247   EXPECT_DEATH(Align(8) / 3, "Divisor must be positive and a power of 2");
248 }
249 
250 TEST(AlignmentDeathTest, InvalidCTors) {
251   EXPECT_DEATH((Align(0)), "Value must not be 0");
252   for (uint64_t Value : getNonPowerOfTwo()) {
253     EXPECT_DEATH((Align(Value)), "Alignment is not a power of 2");
254     EXPECT_DEATH((MaybeAlign(Value)), "Alignment is not 0 or a power of 2");
255   }
256 }
257 
258 TEST(AlignmentDeathTest, ComparisonsWithZero) {
259   for (uint64_t Value : getValidAlignmentsForDeathTest()) {
260     EXPECT_DEATH((void)(Align(Value) == 0), ".* should be defined");
261     EXPECT_DEATH((void)(Align(Value) != 0), ".* should be defined");
262     EXPECT_DEATH((void)(Align(Value) >= 0), ".* should be defined");
263     EXPECT_DEATH((void)(Align(Value) <= 0), ".* should be defined");
264     EXPECT_DEATH((void)(Align(Value) > 0), ".* should be defined");
265     EXPECT_DEATH((void)(Align(Value) < 0), ".* should be defined");
266   }
267 }
268 
269 TEST(AlignmentDeathTest, CompareMaybeAlignToZero) {
270   for (uint64_t Value : getValidAlignmentsForDeathTest()) {
271     // MaybeAlign is allowed to be == or != 0
272     (void)(MaybeAlign(Value) == 0);
273     (void)(MaybeAlign(Value) != 0);
274     EXPECT_DEATH((void)(MaybeAlign(Value) >= 0), ".* should be defined");
275     EXPECT_DEATH((void)(MaybeAlign(Value) <= 0), ".* should be defined");
276     EXPECT_DEATH((void)(MaybeAlign(Value) > 0), ".* should be defined");
277     EXPECT_DEATH((void)(MaybeAlign(Value) < 0), ".* should be defined");
278   }
279 }
280 
281 TEST(AlignmentDeathTest, CompareAlignToUndefMaybeAlign) {
282   for (uint64_t Value : getValidAlignmentsForDeathTest()) {
283     EXPECT_DEATH((void)(Align(Value) == MaybeAlign(0)), ".* should be defined");
284     EXPECT_DEATH((void)(Align(Value) != MaybeAlign(0)), ".* should be defined");
285     EXPECT_DEATH((void)(Align(Value) >= MaybeAlign(0)), ".* should be defined");
286     EXPECT_DEATH((void)(Align(Value) <= MaybeAlign(0)), ".* should be defined");
287     EXPECT_DEATH((void)(Align(Value) > MaybeAlign(0)), ".* should be defined");
288     EXPECT_DEATH((void)(Align(Value) < MaybeAlign(0)), ".* should be defined");
289   }
290 }
291 
292 #endif // NDEBUG
293 
294 } // end anonymous namespace
295