1 //===- llvm/unittest/ADT/ArrayRefTest.cpp - ArrayRef unit 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/ADT/ArrayRef.h"
10 #include "llvm/Support/Allocator.h"
11 #include "llvm/Support/raw_ostream.h"
12 #include "gtest/gtest.h"
13 #include <limits>
14 #include <vector>
15 using namespace llvm;
16 
17 // Check that the ArrayRef-of-pointer converting constructor only allows adding
18 // cv qualifiers (not removing them, or otherwise changing the type)
19 static_assert(
20     std::is_convertible<ArrayRef<int *>, ArrayRef<const int *>>::value,
21     "Adding const");
22 static_assert(
23     std::is_convertible<ArrayRef<int *>, ArrayRef<volatile int *>>::value,
24     "Adding volatile");
25 static_assert(!std::is_convertible<ArrayRef<int *>, ArrayRef<float *>>::value,
26               "Changing pointer of one type to a pointer of another");
27 static_assert(
28     !std::is_convertible<ArrayRef<const int *>, ArrayRef<int *>>::value,
29     "Removing const");
30 static_assert(
31     !std::is_convertible<ArrayRef<volatile int *>, ArrayRef<int *>>::value,
32     "Removing volatile");
33 
34 // Check that we can't accidentally assign a temporary location to an ArrayRef.
35 // (Unfortunately we can't make use of the same thing with constructors.)
36 static_assert(
37     !std::is_assignable<ArrayRef<int *>&, int *>::value,
38     "Assigning from single prvalue element");
39 static_assert(
40     !std::is_assignable<ArrayRef<int *>&, int * &&>::value,
41     "Assigning from single xvalue element");
42 static_assert(
43     std::is_assignable<ArrayRef<int *>&, int * &>::value,
44     "Assigning from single lvalue element");
45 static_assert(
46     !std::is_assignable<ArrayRef<int *>&, std::initializer_list<int *>>::value,
47     "Assigning from an initializer list");
48 
49 namespace {
50 
51 TEST(ArrayRefTest, AllocatorCopy) {
52   BumpPtrAllocator Alloc;
53   static const uint16_t Words1[] = { 1, 4, 200, 37 };
54   ArrayRef<uint16_t> Array1 = makeArrayRef(Words1, 4);
55   static const uint16_t Words2[] = { 11, 4003, 67, 64000, 13 };
56   ArrayRef<uint16_t> Array2 = makeArrayRef(Words2, 5);
57   ArrayRef<uint16_t> Array1c = Array1.copy(Alloc);
58   ArrayRef<uint16_t> Array2c = Array2.copy(Alloc);
59   EXPECT_TRUE(Array1.equals(Array1c));
60   EXPECT_NE(Array1.data(), Array1c.data());
61   EXPECT_TRUE(Array2.equals(Array2c));
62   EXPECT_NE(Array2.data(), Array2c.data());
63 
64   // Check that copy can cope with uninitialized memory.
65   struct NonAssignable {
66     const char *Ptr;
67 
68     NonAssignable(const char *Ptr) : Ptr(Ptr) {}
69     NonAssignable(const NonAssignable &RHS) = default;
70     void operator=(const NonAssignable &RHS) { assert(RHS.Ptr != nullptr); }
71     bool operator==(const NonAssignable &RHS) const { return Ptr == RHS.Ptr; }
72   } Array3Src[] = {"hello", "world"};
73   ArrayRef<NonAssignable> Array3Copy = makeArrayRef(Array3Src).copy(Alloc);
74   EXPECT_EQ(makeArrayRef(Array3Src), Array3Copy);
75   EXPECT_NE(makeArrayRef(Array3Src).data(), Array3Copy.data());
76 }
77 
78 // This test is pure UB given the ArrayRef<> implementation.
79 // You are not allowed to produce non-null pointers given null base pointer.
80 TEST(ArrayRefTest, DISABLED_SizeTSizedOperations) {
81   ArrayRef<char> AR(nullptr, std::numeric_limits<ptrdiff_t>::max());
82 
83   // Check that drop_back accepts size_t-sized numbers.
84   EXPECT_EQ(1U, AR.drop_back(AR.size() - 1).size());
85 
86   // Check that drop_front accepts size_t-sized numbers.
87   EXPECT_EQ(1U, AR.drop_front(AR.size() - 1).size());
88 
89   // Check that slice accepts size_t-sized numbers.
90   EXPECT_EQ(1U, AR.slice(AR.size() - 1).size());
91   EXPECT_EQ(AR.size() - 1, AR.slice(1, AR.size() - 1).size());
92 }
93 
94 TEST(ArrayRefTest, DropBack) {
95   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
96   ArrayRef<int> AR1(TheNumbers);
97   ArrayRef<int> AR2(TheNumbers, AR1.size() - 1);
98   EXPECT_TRUE(AR1.drop_back().equals(AR2));
99 }
100 
101 TEST(ArrayRefTest, DropFront) {
102   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
103   ArrayRef<int> AR1(TheNumbers);
104   ArrayRef<int> AR2(&TheNumbers[2], AR1.size() - 2);
105   EXPECT_TRUE(AR1.drop_front(2).equals(AR2));
106 }
107 
108 TEST(ArrayRefTest, DropWhile) {
109   static const int TheNumbers[] = {1, 3, 5, 8, 10, 11};
110   ArrayRef<int> AR1(TheNumbers);
111   ArrayRef<int> Expected = AR1.drop_front(3);
112   EXPECT_EQ(Expected, AR1.drop_while([](const int &N) { return N % 2 == 1; }));
113 
114   EXPECT_EQ(AR1, AR1.drop_while([](const int &N) { return N < 0; }));
115   EXPECT_EQ(ArrayRef<int>(),
116             AR1.drop_while([](const int &N) { return N > 0; }));
117 }
118 
119 TEST(ArrayRefTest, DropUntil) {
120   static const int TheNumbers[] = {1, 3, 5, 8, 10, 11};
121   ArrayRef<int> AR1(TheNumbers);
122   ArrayRef<int> Expected = AR1.drop_front(3);
123   EXPECT_EQ(Expected, AR1.drop_until([](const int &N) { return N % 2 == 0; }));
124 
125   EXPECT_EQ(ArrayRef<int>(),
126             AR1.drop_until([](const int &N) { return N < 0; }));
127   EXPECT_EQ(AR1, AR1.drop_until([](const int &N) { return N > 0; }));
128 }
129 
130 TEST(ArrayRefTest, TakeBack) {
131   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
132   ArrayRef<int> AR1(TheNumbers);
133   ArrayRef<int> AR2(AR1.end() - 1, 1);
134   EXPECT_TRUE(AR1.take_back().equals(AR2));
135 }
136 
137 TEST(ArrayRefTest, TakeFront) {
138   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
139   ArrayRef<int> AR1(TheNumbers);
140   ArrayRef<int> AR2(AR1.data(), 2);
141   EXPECT_TRUE(AR1.take_front(2).equals(AR2));
142 }
143 
144 TEST(ArrayRefTest, TakeWhile) {
145   static const int TheNumbers[] = {1, 3, 5, 8, 10, 11};
146   ArrayRef<int> AR1(TheNumbers);
147   ArrayRef<int> Expected = AR1.take_front(3);
148   EXPECT_EQ(Expected, AR1.take_while([](const int &N) { return N % 2 == 1; }));
149 
150   EXPECT_EQ(ArrayRef<int>(),
151             AR1.take_while([](const int &N) { return N < 0; }));
152   EXPECT_EQ(AR1, AR1.take_while([](const int &N) { return N > 0; }));
153 }
154 
155 TEST(ArrayRefTest, TakeUntil) {
156   static const int TheNumbers[] = {1, 3, 5, 8, 10, 11};
157   ArrayRef<int> AR1(TheNumbers);
158   ArrayRef<int> Expected = AR1.take_front(3);
159   EXPECT_EQ(Expected, AR1.take_until([](const int &N) { return N % 2 == 0; }));
160 
161   EXPECT_EQ(AR1, AR1.take_until([](const int &N) { return N < 0; }));
162   EXPECT_EQ(ArrayRef<int>(),
163             AR1.take_until([](const int &N) { return N > 0; }));
164 }
165 
166 TEST(ArrayRefTest, Equals) {
167   static const int A1[] = {1, 2, 3, 4, 5, 6, 7, 8};
168   ArrayRef<int> AR1(A1);
169   EXPECT_TRUE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 8}));
170   EXPECT_FALSE(AR1.equals({8, 1, 2, 4, 5, 6, 6, 7}));
171   EXPECT_FALSE(AR1.equals({2, 4, 5, 6, 6, 7, 8, 1}));
172   EXPECT_FALSE(AR1.equals({0, 1, 2, 4, 5, 6, 6, 7}));
173   EXPECT_FALSE(AR1.equals({1, 2, 42, 4, 5, 6, 7, 8}));
174   EXPECT_FALSE(AR1.equals({42, 2, 3, 4, 5, 6, 7, 8}));
175   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 42}));
176   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7}));
177   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 8, 9}));
178 
179   ArrayRef<int> AR1a = AR1.drop_back();
180   EXPECT_TRUE(AR1a.equals({1, 2, 3, 4, 5, 6, 7}));
181   EXPECT_FALSE(AR1a.equals({1, 2, 3, 4, 5, 6, 7, 8}));
182 
183   ArrayRef<int> AR1b = AR1a.slice(2, 4);
184   EXPECT_TRUE(AR1b.equals({3, 4, 5, 6}));
185   EXPECT_FALSE(AR1b.equals({2, 3, 4, 5, 6}));
186   EXPECT_FALSE(AR1b.equals({3, 4, 5, 6, 7}));
187 }
188 
189 TEST(ArrayRefTest, EmptyEquals) {
190   EXPECT_TRUE(ArrayRef<unsigned>() == ArrayRef<unsigned>());
191 }
192 
193 TEST(ArrayRefTest, ConstConvert) {
194   int buf[4];
195   for (int i = 0; i < 4; ++i)
196     buf[i] = i;
197 
198   static int *A[] = {&buf[0], &buf[1], &buf[2], &buf[3]};
199   ArrayRef<const int *> a((ArrayRef<int *>(A)));
200   a = ArrayRef<int *>(A);
201 }
202 
203 static std::vector<int> ReturnTest12() { return {1, 2}; }
204 static void ArgTest12(ArrayRef<int> A) {
205   EXPECT_EQ(2U, A.size());
206   EXPECT_EQ(1, A[0]);
207   EXPECT_EQ(2, A[1]);
208 }
209 
210 TEST(ArrayRefTest, InitializerList) {
211   std::initializer_list<int> init_list = { 0, 1, 2, 3, 4 };
212   ArrayRef<int> A = init_list;
213   for (int i = 0; i < 5; ++i)
214     EXPECT_EQ(i, A[i]);
215 
216   std::vector<int> B = ReturnTest12();
217   A = B;
218   EXPECT_EQ(1, A[0]);
219   EXPECT_EQ(2, A[1]);
220 
221   ArgTest12({1, 2});
222 }
223 
224 TEST(ArrayRefTest, EmptyInitializerList) {
225   ArrayRef<int> A = {};
226   EXPECT_TRUE(A.empty());
227 
228   A = {};
229   EXPECT_TRUE(A.empty());
230 }
231 
232 // Test that makeArrayRef works on ArrayRef (no-op)
233 TEST(ArrayRefTest, makeArrayRef) {
234   static const int A1[] = {1, 2, 3, 4, 5, 6, 7, 8};
235 
236   // No copy expected for non-const ArrayRef (true no-op)
237   ArrayRef<int> AR1(A1);
238   ArrayRef<int> &AR1Ref = makeArrayRef(AR1);
239   EXPECT_EQ(&AR1, &AR1Ref);
240 
241   // A copy is expected for non-const ArrayRef (thin copy)
242   const ArrayRef<int> AR2(A1);
243   const ArrayRef<int> &AR2Ref = makeArrayRef(AR2);
244   EXPECT_NE(&AR2Ref, &AR2);
245   EXPECT_TRUE(AR2.equals(AR2Ref));
246 }
247 
248 TEST(ArrayRefTest, OwningArrayRef) {
249   static const int A1[] = {0, 1};
250   OwningArrayRef<int> A(makeArrayRef(A1));
251   OwningArrayRef<int> B(std::move(A));
252   EXPECT_EQ(A.data(), nullptr);
253 }
254 
255 TEST(ArrayRefTest, makeArrayRefFromStdArray) {
256   std::array<int, 5> A1{{42, -5, 0, 1000000, -1000000}};
257   ArrayRef<int> A2 = makeArrayRef(A1);
258 
259   EXPECT_EQ(A1.size(), A2.size());
260   for (std::size_t i = 0; i < A1.size(); ++i) {
261     EXPECT_EQ(A1[i], A2[i]);
262   }
263 }
264 
265 static_assert(std::is_trivially_copyable<ArrayRef<int>>::value,
266               "trivially copyable");
267 
268 } // end anonymous namespace
269