1 //===- llvm/unittest/ADT/ArrayRefTest.cpp - ArrayRef unit 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/ADT/ArrayRef.h"
11 #include "llvm/Support/Allocator.h"
12 #include "llvm/Support/raw_ostream.h"
13 #include "gtest/gtest.h"
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, DropBack) {
84   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
85   ArrayRef<int> AR1(TheNumbers);
86   ArrayRef<int> AR2(TheNumbers, AR1.size() - 1);
87   EXPECT_TRUE(AR1.drop_back().equals(AR2));
88 
89   // Check that drop_back accepts size_t-sized numbers.
90   ArrayRef<char> AR3((const char *)0x10000, SIZE_MAX - 0x10000);
91   EXPECT_EQ(1U, AR3.drop_back(AR3.size() - 1).size());
92 }
93 
94 TEST(ArrayRefTest, DropFront) {
95   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
96   ArrayRef<int> AR1(TheNumbers);
97   ArrayRef<int> AR2(&TheNumbers[2], AR1.size() - 2);
98   EXPECT_TRUE(AR1.drop_front(2).equals(AR2));
99 
100   // Check that drop_front accepts size_t-sized numbers.
101   ArrayRef<char> AR3((const char *)0x10000, SIZE_MAX - 0x10000);
102   EXPECT_EQ(1U, AR3.drop_front(AR3.size() - 1).size());
103 }
104 
105 TEST(ArrayRefTest, TakeBack) {
106   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
107   ArrayRef<int> AR1(TheNumbers);
108   ArrayRef<int> AR2(AR1.end() - 1, 1);
109   EXPECT_TRUE(AR1.take_back().equals(AR2));
110 }
111 
112 TEST(ArrayRefTest, TakeFront) {
113   static const int TheNumbers[] = {4, 8, 15, 16, 23, 42};
114   ArrayRef<int> AR1(TheNumbers);
115   ArrayRef<int> AR2(AR1.data(), 2);
116   EXPECT_TRUE(AR1.take_front(2).equals(AR2));
117 }
118 
119 TEST(ArrayRefTest, Equals) {
120   static const int A1[] = {1, 2, 3, 4, 5, 6, 7, 8};
121   ArrayRef<int> AR1(A1);
122   EXPECT_TRUE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 8}));
123   EXPECT_FALSE(AR1.equals({8, 1, 2, 4, 5, 6, 6, 7}));
124   EXPECT_FALSE(AR1.equals({2, 4, 5, 6, 6, 7, 8, 1}));
125   EXPECT_FALSE(AR1.equals({0, 1, 2, 4, 5, 6, 6, 7}));
126   EXPECT_FALSE(AR1.equals({1, 2, 42, 4, 5, 6, 7, 8}));
127   EXPECT_FALSE(AR1.equals({42, 2, 3, 4, 5, 6, 7, 8}));
128   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 42}));
129   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7}));
130   EXPECT_FALSE(AR1.equals({1, 2, 3, 4, 5, 6, 7, 8, 9}));
131 
132   ArrayRef<int> AR1a = AR1.drop_back();
133   EXPECT_TRUE(AR1a.equals({1, 2, 3, 4, 5, 6, 7}));
134   EXPECT_FALSE(AR1a.equals({1, 2, 3, 4, 5, 6, 7, 8}));
135 
136   ArrayRef<int> AR1b = AR1a.slice(2, 4);
137   EXPECT_TRUE(AR1b.equals({3, 4, 5, 6}));
138   EXPECT_FALSE(AR1b.equals({2, 3, 4, 5, 6}));
139   EXPECT_FALSE(AR1b.equals({3, 4, 5, 6, 7}));
140 }
141 
142 TEST(ArrayRefTest, EmptyEquals) {
143   EXPECT_TRUE(ArrayRef<unsigned>() == ArrayRef<unsigned>());
144 }
145 
146 TEST(ArrayRefTest, Slice) {
147   // Check that slice accepts size_t-sized numbers.
148   ArrayRef<char> AR((const char *)0x10000, SIZE_MAX - 0x10000);
149   EXPECT_EQ(1U, AR.slice(AR.size() - 1).size());
150   EXPECT_EQ(AR.size() - 1, AR.slice(1, AR.size() - 1).size());
151 }
152 
153 TEST(ArrayRefTest, ConstConvert) {
154   int buf[4];
155   for (int i = 0; i < 4; ++i)
156     buf[i] = i;
157 
158   static int *A[] = {&buf[0], &buf[1], &buf[2], &buf[3]};
159   ArrayRef<const int *> a((ArrayRef<int *>(A)));
160   a = ArrayRef<int *>(A);
161 }
162 
163 static std::vector<int> ReturnTest12() { return {1, 2}; }
164 static void ArgTest12(ArrayRef<int> A) {
165   EXPECT_EQ(2U, A.size());
166   EXPECT_EQ(1, A[0]);
167   EXPECT_EQ(2, A[1]);
168 }
169 
170 TEST(ArrayRefTest, InitializerList) {
171   std::initializer_list<int> init_list = { 0, 1, 2, 3, 4 };
172   ArrayRef<int> A = init_list;
173   for (int i = 0; i < 5; ++i)
174     EXPECT_EQ(i, A[i]);
175 
176   std::vector<int> B = ReturnTest12();
177   A = B;
178   EXPECT_EQ(1, A[0]);
179   EXPECT_EQ(2, A[1]);
180 
181   ArgTest12({1, 2});
182 }
183 
184 TEST(ArrayRefTest, EmptyInitializerList) {
185   ArrayRef<int> A = {};
186   EXPECT_TRUE(A.empty());
187 
188   A = {};
189   EXPECT_TRUE(A.empty());
190 }
191 
192 // Test that makeArrayRef works on ArrayRef (no-op)
193 TEST(ArrayRefTest, makeArrayRef) {
194   static const int A1[] = {1, 2, 3, 4, 5, 6, 7, 8};
195 
196   // No copy expected for non-const ArrayRef (true no-op)
197   ArrayRef<int> AR1(A1);
198   ArrayRef<int> &AR1Ref = makeArrayRef(AR1);
199   EXPECT_EQ(&AR1, &AR1Ref);
200 
201   // A copy is expected for non-const ArrayRef (thin copy)
202   const ArrayRef<int> AR2(A1);
203   const ArrayRef<int> &AR2Ref = makeArrayRef(AR2);
204   EXPECT_NE(&AR2Ref, &AR2);
205   EXPECT_TRUE(AR2.equals(AR2Ref));
206 }
207 
208 } // end anonymous namespace
209