xref: /llvm-project/clang/test/Analysis/builtin-functions.cpp (revision 566363981bb9ff6a6081490f05aa6b19aefc16f0)
1 // RUN: %clang_analyze_cc1 -triple x86_64-apple-darwin10 -analyzer-checker=core,debug.ExprInspection %s -std=c++11 -verify
2 // RUN: %clang_analyze_cc1 -triple x86_64-pc-windows-msvc19.11.0 -fms-extensions -analyzer-checker=core,debug.ExprInspection %s -std=c++11 -verify
3 
4 #include "Inputs/system-header-simulator-cxx.h"
5 
6 namespace std {
7 // Intentionally not using an "auto" return type here, as such must also have a definition.
8 template <typename T, typename U> constexpr int&& forward_like(U&& x) noexcept;
9 template <typename T> const T& move_if_noexcept(T& x) noexcept;
10 } // namespace std
11 
12 template <typename T> void clang_analyzer_dump_ref(T&&);
13 template <typename T> void clang_analyzer_dump_ptr(T*);
14 void clang_analyzer_eval(bool);
15 void clang_analyzer_warnIfReached();
16 
17 void testAddressof(int x) {
18   clang_analyzer_eval(&x == __builtin_addressof(x)); // expected-warning{{TRUE}}
19 }
20 
21 void testStdBuiltinLikeFunctions(int x) {
22   clang_analyzer_dump_ptr(std::addressof(x));           // expected-warning{{&x}}
23   clang_analyzer_dump_ptr(std::__addressof(x));         // expected-warning{{&x}}
24   clang_analyzer_dump_ref(std::as_const(x));            // expected-warning{{&x}}
25   clang_analyzer_dump_ref(std::forward<int &>(x));      // expected-warning{{&x}}
26   clang_analyzer_dump_ref(std::forward_like<int &>(x)); // expected-warning{{&x}}
27   clang_analyzer_dump_ref(std::move(x));                // expected-warning{{&x}}
28   clang_analyzer_dump_ref(std::move_if_noexcept(x));    // expected-warning{{&x}}
29 }
30 
31 void testSize() {
32   struct {
33     int x;
34     int y;
35     char z;
36   } object;
37   clang_analyzer_eval(__builtin_object_size(&object.y, 0) == sizeof(object) - sizeof(int)); // expected-warning{{TRUE}}
38 
39   // Clang can't actually evaluate these builtin "calls", but importantly they don't actually evaluate the argument expression either.
40   int i = 0;
41   char buf[10];
42   clang_analyzer_eval(__builtin_object_size(&buf[i++], 0) == sizeof(buf)); // expected-warning{{FALSE}}
43   clang_analyzer_eval(__builtin_object_size(&buf[++i], 0) == sizeof(buf) - 1); // expected-warning{{FALSE}}
44 
45   clang_analyzer_eval(i == 0); // expected-warning{{TRUE}}
46 }
47 
48 void test_assume_aligned_1(char *p) {
49   char *q;
50 
51   q = (char*) __builtin_assume_aligned(p, 16);
52   clang_analyzer_eval(p == q); // expected-warning{{TRUE}}
53 }
54 
55 void test_assume_aligned_2(char *p) {
56   char *q;
57 
58   q = (char*) __builtin_assume_aligned(p, 16, 8);
59   clang_analyzer_eval(p == q); // expected-warning{{TRUE}}
60 }
61 
62 void test_assume_aligned_3(char *p) {
63   void *q;
64 
65   q = __builtin_assume_aligned(p, 16, 8);
66   clang_analyzer_eval(p == q); // expected-warning{{TRUE}}
67 }
68 
69 void test_assume_aligned_4(char *p) {
70   char *q;
71 
72   q = (char*) __builtin_assume_aligned(p + 1, 16);
73   clang_analyzer_eval(p == q); // expected-warning{{FALSE}}
74 }
75 
76 void f(int i) {
77   __builtin_assume(i < 10);
78   clang_analyzer_eval(i < 15); // expected-warning {{TRUE}}
79 }
80 
81 void g(int i) {
82   if (i > 5) {
83     __builtin_assume(i < 5);
84     clang_analyzer_warnIfReached(); // Assumtion contradicts constraints.
85                                     // We give up the analysis on this path.
86   }
87 }
88 
89 #ifdef _WIN32
90 namespace ms {
91 void f(int i) {
92   __assume(i < 10);
93   clang_analyzer_eval(i < 15); // expected-warning {{TRUE}}
94 }
95 
96 void g(int i) {
97   if (i > 5) {
98     __assume(i < 5);
99     clang_analyzer_warnIfReached(); // Assumtion contradicts constraints.
100                                     // We give up the analysis on this path.
101   }
102 }
103 } // namespace ms
104 #endif
105 
106 void test_constant_p(void *ptr) {
107   int i = 1;
108   const int j = 2;
109   constexpr int k = 3;
110   clang_analyzer_eval(__builtin_constant_p(42) == 1); // expected-warning {{TRUE}}
111   clang_analyzer_eval(__builtin_constant_p(i) == 0); // expected-warning {{TRUE}}
112   clang_analyzer_eval(__builtin_constant_p(j) == 1); // expected-warning {{TRUE}}
113   clang_analyzer_eval(__builtin_constant_p(k) == 1); // expected-warning {{TRUE}}
114   clang_analyzer_eval(__builtin_constant_p(i + 42) == 0); // expected-warning {{TRUE}}
115   clang_analyzer_eval(__builtin_constant_p(j + 42) == 1); // expected-warning {{TRUE}}
116   clang_analyzer_eval(__builtin_constant_p(k + 42) == 1); // expected-warning {{TRUE}}
117   clang_analyzer_eval(__builtin_constant_p(" ") == 1); // expected-warning {{TRUE}}
118   clang_analyzer_eval(__builtin_constant_p(test_constant_p) == 0); // expected-warning {{TRUE}}
119   clang_analyzer_eval(__builtin_constant_p(k - 3) == 0); // expected-warning {{FALSE}}
120   clang_analyzer_eval(__builtin_constant_p(k - 3) == 1); // expected-warning {{TRUE}}
121   clang_analyzer_eval(__builtin_constant_p(ptr == 0)); // expected-warning {{FALSE}}
122 }
123