constant-folding.c revision a0decc9a2481f938e1675b4f7bbd58761a882a36 
1// RUN: %clang_cc1 -analyze -analyzer-experimental-internal-checks -analyzer-checker=core.experimental.UnreachableCode -analyzer-check-objc-mem -analyzer-experimental-checks -verify %s
2
3// Trigger a warning if the analyzer reaches this point in the control flow.
4#define WARN ((void)*(char*)0)
5
6// There should be no warnings unless otherwise indicated.
7
8void testComparisons (int a) {
9  // Sema can already catch the simple comparison a==a,
10  // since that's usually a logic error (and not path-dependent).
11  int b = a;
12  if (!(b==a)) WARN; // expected-warning{{never executed}}
13  if (!(b>=a)) WARN; // expected-warning{{never executed}}
14  if (!(b<=a)) WARN; // expected-warning{{never executed}}
15  if (b!=a) WARN;    // expected-warning{{never executed}}
16  if (b>a) WARN;     // expected-warning{{never executed}}
17  if (b<a) WARN;     // expected-warning{{never executed}}
18}
19
20void testSelfOperations (int a) {
21  if ((a|a) != a) WARN; // expected-warning{{never executed}}
22  if ((a&a) != a) WARN; // expected-warning{{never executed}}
23  if ((a^a) != 0) WARN; // expected-warning{{never executed}}
24  if ((a-a) != 0) WARN; // expected-warning{{never executed}}
25}
26
27void testIdempotent (int a) {
28  if ((a*1) != a) WARN;    // expected-warning{{never executed}}
29  if ((a/1) != a) WARN;    // expected-warning{{never executed}}
30  if ((a+0) != a) WARN;    // expected-warning{{never executed}}
31  if ((a-0) != a) WARN;    // expected-warning{{never executed}}
32  if ((a<<0) != a) WARN;   // expected-warning{{never executed}}
33  if ((a>>0) != a) WARN;   // expected-warning{{never executed}}
34  if ((a^0) != a) WARN;    // expected-warning{{never executed}}
35  if ((a&(~0)) != a) WARN; // expected-warning{{never executed}}
36  if ((a|0) != a) WARN;    // expected-warning{{never executed}}
37}
38
39void testReductionToConstant (int a) {
40  if ((a*0) != 0) WARN; // expected-warning{{never executed}}
41  if ((a&0) != 0) WARN; // expected-warning{{never executed}}
42  if ((a|(~0)) != (~0)) WARN; // expected-warning{{never executed}}
43}
44
45void testSymmetricIntSymOperations (int a) {
46  if ((2+a) != (a+2)) WARN; // expected-warning{{never executed}}
47  if ((2*a) != (a*2)) WARN; // expected-warning{{never executed}}
48  if ((2&a) != (a&2)) WARN; // expected-warning{{never executed}}
49  if ((2^a) != (a^2)) WARN; // expected-warning{{never executed}}
50  if ((2|a) != (a|2)) WARN; // expected-warning{{never executed}}
51}
52
53void testAsymmetricIntSymOperations (int a) {
54  if (((~0) >> a) != (~0)) WARN; // expected-warning{{never executed}}
55  if ((0 >> a) != 0) WARN; // expected-warning{{never executed}}
56  if ((0 << a) != 0) WARN; // expected-warning{{never executed}}
57
58  // Unsigned right shift shifts in zeroes.
59  if ((((unsigned)(~0)) >> ((unsigned) a)) != ((unsigned)(~0)))
60    WARN; // expected-warning{{}}
61}
62
63void testLocations (char *a) {
64  char *b = a;
65  if (!(b==a)) WARN; // expected-warning{{never executed}}
66  if (!(b>=a)) WARN; // expected-warning{{never executed}}
67  if (!(b<=a)) WARN; // expected-warning{{never executed}}
68  if (b!=a) WARN; // expected-warning{{never executed}}
69  if (b>a) WARN; // expected-warning{{never executed}}
70  if (b<a) WARN; // expected-warning{{never executed}}
71  if (b-a) WARN; // expected-warning{{never executed}}
72}
73