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Diffstat (limited to 'clang/test/Analysis/constant-folding.c')
| -rw-r--r-- | clang/test/Analysis/constant-folding.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/clang/test/Analysis/constant-folding.c b/clang/test/Analysis/constant-folding.c new file mode 100644 index 0000000..e7a5705 --- /dev/null +++ b/clang/test/Analysis/constant-folding.c @@ -0,0 +1,72 @@ +// RUN: %clang_cc1 -analyze -analyzer-checker=core,experimental.deadcode.UnreachableCode -Wno-null-dereference -verify %s + +// Trigger a warning if the analyzer reaches this point in the control flow. +#define WARN ((void)*(char*)0) + +// There should be no warnings unless otherwise indicated. + +void testComparisons (int a) { + // Sema can already catch the simple comparison a==a, + // since that's usually a logic error (and not path-dependent). + int b = a; + if (!(b==a)) WARN; // expected-warning{{never executed}} + if (!(b>=a)) WARN; // expected-warning{{never executed}} + if (!(b<=a)) WARN; // expected-warning{{never executed}} + if (b!=a) WARN; // expected-warning{{never executed}} + if (b>a) WARN; // expected-warning{{never executed}} + if (b<a) WARN; // expected-warning{{never executed}} +} + +void testSelfOperations (int a) { + if ((a|a) != a) WARN; // expected-warning{{never executed}} + if ((a&a) != a) WARN; // expected-warning{{never executed}} + if ((a^a) != 0) WARN; // expected-warning{{never executed}} + if ((a-a) != 0) WARN; // expected-warning{{never executed}} +} + +void testIdempotent (int a) { + if ((a*1) != a) WARN; // expected-warning{{never executed}} + if ((a/1) != a) WARN; // expected-warning{{never executed}} + if ((a+0) != a) WARN; // expected-warning{{never executed}} + if ((a-0) != a) WARN; // expected-warning{{never executed}} + if ((a<<0) != a) WARN; // expected-warning{{never executed}} + if ((a>>0) != a) WARN; // expected-warning{{never executed}} + if ((a^0) != a) WARN; // expected-warning{{never executed}} + if ((a&(~0)) != a) WARN; // expected-warning{{never executed}} + if ((a|0) != a) WARN; // expected-warning{{never executed}} +} + +void testReductionToConstant (int a) { + if ((a*0) != 0) WARN; // expected-warning{{never executed}} + if ((a&0) != 0) WARN; // expected-warning{{never executed}} + if ((a|(~0)) != (~0)) WARN; // expected-warning{{never executed}} +} + +void testSymmetricIntSymOperations (int a) { + if ((2+a) != (a+2)) WARN; // expected-warning{{never executed}} + if ((2*a) != (a*2)) WARN; // expected-warning{{never executed}} + if ((2&a) != (a&2)) WARN; // expected-warning{{never executed}} + if ((2^a) != (a^2)) WARN; // expected-warning{{never executed}} + if ((2|a) != (a|2)) WARN; // expected-warning{{never executed}} +} + +void testAsymmetricIntSymOperations (int a) { + if (((~0) >> a) != (~0)) WARN; // expected-warning{{never executed}} + if ((0 >> a) != 0) WARN; // expected-warning{{never executed}} + if ((0 << a) != 0) WARN; // expected-warning{{never executed}} + + // Unsigned right shift shifts in zeroes. + if ((((unsigned)(~0)) >> ((unsigned) a)) != ((unsigned)(~0))) + WARN; // expected-warning{{}} +} + +void testLocations (char *a) { + char *b = a; + if (!(b==a)) WARN; // expected-warning{{never executed}} + if (!(b>=a)) WARN; // expected-warning{{never executed}} + if (!(b<=a)) WARN; // expected-warning{{never executed}} + if (b!=a) WARN; // expected-warning{{never executed}} + if (b>a) WARN; // expected-warning{{never executed}} + if (b<a) WARN; // expected-warning{{never executed}} + if (b-a) WARN; // expected-warning{{never executed}} +} |