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 //
37 // Disable this check under MSVC; even MSVC 2015 isn't inconsistent between
38 // std::is_assignable and actually writing such an assignment.
39 #if !defined(_MSC_VER)
40 static_assert(
41     !std::is_assignable<ArrayRef<int *>&, int *>::value,
42     "Assigning from single prvalue element");
43 static_assert(
44     !std::is_assignable<ArrayRef<int *>&, int * &&>::value,
45     "Assigning from single xvalue element");
46 static_assert(
47     std::is_assignable<ArrayRef<int *>&, int * &>::value,
48     "Assigning from single lvalue element");
49 static_assert(
50     !std::is_assignable<ArrayRef<int *>&, std::initializer_list<int *>>::value,
51     "Assigning from an initializer list");
52 #endif
53 
54 namespace {
55 
56 TEST(ArrayRefTest, AllocatorCopy) {
57   BumpPtrAllocator Alloc;
58   static const uint16_t Words1[] = { 1, 4, 200, 37 };
59   ArrayRef<uint16_t> Array1 = makeArrayRef(Words1, 4);
60   static const uint16_t Words2[] = { 11, 4003, 67, 64000, 13 };
61   ArrayRef<uint16_t> Array2 = makeArrayRef(Words2, 5);
62   ArrayRef<uint16_t> Array1c = Array1.copy(Alloc);
63   ArrayRef<uint16_t> Array2c = Array2.copy(Alloc);
64   EXPECT_TRUE(Array1.equals(Array1c));
65   EXPECT_NE(Array1.data(), Array1c.data());
66   EXPECT_TRUE(Array2.equals(Array2c));
67   EXPECT_NE(Array2.data(), Array2c.data());
68 
69   // Check that copy can cope with uninitialized memory.
70   struct NonAssignable {
71     const char *Ptr;
72 
73     NonAssignable(const char *Ptr) : Ptr(Ptr) {}
74     NonAssignable(const NonAssignable &RHS) = default;
75     void operator=(const NonAssignable &RHS) { assert(RHS.Ptr != nullptr); }
76     bool operator==(const NonAssignable &RHS) const { return Ptr == RHS.Ptr; }
77   } Array3Src[] = {"hello", "world"};
78   ArrayRef<NonAssignable> Array3Copy = makeArrayRef(Array3Src).copy(Alloc);
79   EXPECT_EQ(makeArrayRef(Array3Src), Array3Copy);
80   EXPECT_NE(makeArrayRef(Array3Src).data(), Array3Copy.data());
81 }
82 
83 TEST(ArrayRefTest, SizeTSizedOperations) {
84   ArrayRef<char> AR(nullptr, std::numeric_limits<ptrdiff_t>::max());
85 
86   // Check that drop_back accepts size_t-sized numbers.
87   EXPECT_EQ(1U, AR.drop_back(AR.size() - 1).size());
88 
89   // Check that drop_front accepts size_t-sized numbers.
90   EXPECT_EQ(1U, AR.drop_front(AR.size() - 1).size());
91 
92   // Check that slice accepts size_t-sized numbers.
93   EXPECT_EQ(1U, AR.slice(AR.size() - 1).size());
94   EXPECT_EQ(AR.size() - 1, AR.slice(1, AR.size() - 1).size());
95 }
96 
97 TEST(ArrayRefTest, DropBack) {
98   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
99   ArrayRef<int> AR1(TheNumbers);
100   ArrayRef<int> AR2(TheNumbers, AR1.size() - 1);
101   EXPECT_TRUE(AR1.drop_back().equals(AR2));
102 }
103 
104 TEST(ArrayRefTest, DropFront) {
105   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
106   ArrayRef<int> AR1(TheNumbers);
107   ArrayRef<int> AR2(&TheNumbers[2], AR1.size() - 2);
108   EXPECT_TRUE(AR1.drop_front(2).equals(AR2));
109 }
110 
111 TEST(ArrayRefTest, DropWhile) {
112   static const int TheNumbers[] = {1, 3, 5, 8, 10, 11};
113   ArrayRef<int> AR1(TheNumbers);
114   ArrayRef<int> Expected = AR1.drop_front(3);
115   EXPECT_EQ(Expected, AR1.drop_while([](const int &N) { return N % 2 == 1; }));
116 
117   EXPECT_EQ(AR1, AR1.drop_while([](const int &N) { return N < 0; }));
118   EXPECT_EQ(ArrayRef<int>(),
119             AR1.drop_while([](const int &N) { return N > 0; }));
120 }
121 
122 TEST(ArrayRefTest, DropUntil) {
123   static const int TheNumbers[] = {1, 3, 5, 8, 10, 11};
124   ArrayRef<int> AR1(TheNumbers);
125   ArrayRef<int> Expected = AR1.drop_front(3);
126   EXPECT_EQ(Expected, AR1.drop_until([](const int &N) { return N % 2 == 0; }));
127 
128   EXPECT_EQ(ArrayRef<int>(),
129             AR1.drop_until([](const int &N) { return N < 0; }));
130   EXPECT_EQ(AR1, AR1.drop_until([](const int &N) { return N > 0; }));
131 }
132 
133 TEST(ArrayRefTest, TakeBack) {
134   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
135   ArrayRef<int> AR1(TheNumbers);
136   ArrayRef<int> AR2(AR1.end() - 1, 1);
137   EXPECT_TRUE(AR1.take_back().equals(AR2));
138 }
139 
140 TEST(ArrayRefTest, TakeFront) {
141   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
142   ArrayRef<int> AR1(TheNumbers);
143   ArrayRef<int> AR2(AR1.data(), 2);
144   EXPECT_TRUE(AR1.take_front(2).equals(AR2));
145 }
146 
147 TEST(ArrayRefTest, TakeWhile) {
148   static const int TheNumbers[] = {1, 3, 5, 8, 10, 11};
149   ArrayRef<int> AR1(TheNumbers);
150   ArrayRef<int> Expected = AR1.take_front(3);
151   EXPECT_EQ(Expected, AR1.take_while([](const int &N) { return N % 2 == 1; }));
152 
153   EXPECT_EQ(ArrayRef<int>(),
154             AR1.take_while([](const int &N) { return N < 0; }));
155   EXPECT_EQ(AR1, AR1.take_while([](const int &N) { return N > 0; }));
156 }
157 
158 TEST(ArrayRefTest, TakeUntil) {
159   static const int TheNumbers[] = {1, 3, 5, 8, 10, 11};
160   ArrayRef<int> AR1(TheNumbers);
161   ArrayRef<int> Expected = AR1.take_front(3);
162   EXPECT_EQ(Expected, AR1.take_until([](const int &N) { return N % 2 == 0; }));
163 
164   EXPECT_EQ(AR1, AR1.take_until([](const int &N) { return N < 0; }));
165   EXPECT_EQ(ArrayRef<int>(),
166             AR1.take_until([](const int &N) { return N > 0; }));
167 }
168 
169 TEST(ArrayRefTest, Equals) {
170   static const int A1[] = {1, 2, 3, 4, 5, 6, 7, 8};
171   ArrayRef<int> AR1(A1);
172   EXPECT_TRUE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 8}));
173   EXPECT_FALSE(AR1.equals({8, 1, 2, 4, 5, 6, 6, 7}));
174   EXPECT_FALSE(AR1.equals({2, 4, 5, 6, 6, 7, 8, 1}));
175   EXPECT_FALSE(AR1.equals({0, 1, 2, 4, 5, 6, 6, 7}));
176   EXPECT_FALSE(AR1.equals({1, 2, 42, 4, 5, 6, 7, 8}));
177   EXPECT_FALSE(AR1.equals({42, 2, 3, 4, 5, 6, 7, 8}));
178   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 42}));
179   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7}));
180   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 8, 9}));
181 
182   ArrayRef<int> AR1a = AR1.drop_back();
183   EXPECT_TRUE(AR1a.equals({1, 2, 3, 4, 5, 6, 7}));
184   EXPECT_FALSE(AR1a.equals({1, 2, 3, 4, 5, 6, 7, 8}));
185 
186   ArrayRef<int> AR1b = AR1a.slice(2, 4);
187   EXPECT_TRUE(AR1b.equals({3, 4, 5, 6}));
188   EXPECT_FALSE(AR1b.equals({2, 3, 4, 5, 6}));
189   EXPECT_FALSE(AR1b.equals({3, 4, 5, 6, 7}));
190 }
191 
192 TEST(ArrayRefTest, EmptyEquals) {
193   EXPECT_TRUE(ArrayRef<unsigned>() == ArrayRef<unsigned>());
194 }
195 
196 TEST(ArrayRefTest, ConstConvert) {
197   int buf[4];
198   for (int i = 0; i < 4; ++i)
199     buf[i] = i;
200 
201   static int *A[] = {&buf[0], &buf[1], &buf[2], &buf[3]};
202   ArrayRef<const int *> a((ArrayRef<int *>(A)));
203   a = ArrayRef<int *>(A);
204 }
205 
206 static std::vector<int> ReturnTest12() { return {1, 2}; }
207 static void ArgTest12(ArrayRef<int> A) {
208   EXPECT_EQ(2U, A.size());
209   EXPECT_EQ(1, A[0]);
210   EXPECT_EQ(2, A[1]);
211 }
212 
213 TEST(ArrayRefTest, InitializerList) {
214   std::initializer_list<int> init_list = { 0, 1, 2, 3, 4 };
215   ArrayRef<int> A = init_list;
216   for (int i = 0; i < 5; ++i)
217     EXPECT_EQ(i, A[i]);
218 
219   std::vector<int> B = ReturnTest12();
220   A = B;
221   EXPECT_EQ(1, A[0]);
222   EXPECT_EQ(2, A[1]);
223 
224   ArgTest12({1, 2});
225 }
226 
227 TEST(ArrayRefTest, EmptyInitializerList) {
228   ArrayRef<int> A = {};
229   EXPECT_TRUE(A.empty());
230 
231   A = {};
232   EXPECT_TRUE(A.empty());
233 }
234 
235 // Test that makeArrayRef works on ArrayRef (no-op)
236 TEST(ArrayRefTest, makeArrayRef) {
237   static const int A1[] = {1, 2, 3, 4, 5, 6, 7, 8};
238 
239   // No copy expected for non-const ArrayRef (true no-op)
240   ArrayRef<int> AR1(A1);
241   ArrayRef<int> &AR1Ref = makeArrayRef(AR1);
242   EXPECT_EQ(&AR1, &AR1Ref);
243 
244   // A copy is expected for non-const ArrayRef (thin copy)
245   const ArrayRef<int> AR2(A1);
246   const ArrayRef<int> &AR2Ref = makeArrayRef(AR2);
247   EXPECT_NE(&AR2Ref, &AR2);
248   EXPECT_TRUE(AR2.equals(AR2Ref));
249 }
250 
251 static_assert(is_trivially_copyable<ArrayRef<int>>::value,
252               "trivially copyable");
253 
254 } // end anonymous namespace
255