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| author | Jiri Slaby <jirislaby@gmail.com> | 2018-06-15 10:32:26 +0200 |
|---|---|---|
| committer | Cristian Cadar <c.cadar@imperial.ac.uk> | 2018-07-10 23:26:42 +0100 |
| commit | f30de64e0babbcc68e1611ea4f191ca20c80a837 (patch) | |
| tree | 57499f018cd9cce2e8e1350e4f51aeb3f9d45a24 | |
| parent | 44eb0541fa55f4a7a35af9eaa295ef41c46b3af1 (diff) | |
| download | klee-f30de64e0babbcc68e1611ea4f191ca20c80a837.tar.gz | |
test: remove undefined behaviour
Shifting negative values is implementation-defined. Shifting by equal number of the bits as is the size of the type is undefined. So fix both of these. This fixes #911. Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
| -rw-r--r-- | test/Feature/arithmetic-right-overshift-sym-conc.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/test/Feature/arithmetic-right-overshift-sym-conc.c b/test/Feature/arithmetic-right-overshift-sym-conc.c index 7af6f9d7..6a9bbc21 100644 --- a/test/Feature/arithmetic-right-overshift-sym-conc.c +++ b/test/Feature/arithmetic-right-overshift-sym-conc.c @@ -13,6 +13,8 @@ typedef enum UNKNOWN } overshift_t; +#define INT_31_BITS (0xffffffff >> 1) + // We're using signed ints so should be doing // arithmetic right shift. // lhs should be a constant @@ -20,7 +22,7 @@ int overshift(signed int lhs, volatile unsigned int y, const char * type) { overshift_t ret; volatile signed int x = lhs; - unsigned int limit = sizeof(x)*8; + unsigned int limit = sizeof(x)*8 - 1; assert(!klee_is_symbolic(x)); volatile signed int result; @@ -47,12 +49,12 @@ int overshift(signed int lhs, volatile unsigned int y, const char * type) int main(int argc, char** argv) { - volatile unsigned int y = sizeof(unsigned int)*8; + volatile unsigned int y = sizeof(unsigned int)*8 - 1; // Try with +ve lhs overshift_t conc = overshift(15, y, "Concrete"); assert(conc == TO_ZERO); // Try with -ve lhs - conc = overshift(-1, y, "Concrete"); + conc = overshift(INT_31_BITS, y, "Concrete"); assert(conc == TO_ZERO); // Symbolic overshift @@ -65,7 +67,7 @@ int main(int argc, char** argv) overshift_t sym = overshift(15, y2, "Symbolic"); assert(sym == TO_ZERO); // Try with -ve lhs - sym = overshift(-1, y2, "Symbolic"); + sym = overshift(INT_31_BITS, y2, "Symbolic"); assert(sym == TO_ZERO); // Concrete and symbolic behaviour should be the same |