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/* { dg-do compile } */
/* { dg-options "-O2 -fdump-tree-optimized" } */
/* PR tree-optimization/101590 */
/* These are the signed integer versions
of `(a & b) CMP a` and `(a | b) CMP a`
which can be optimized to 0. */
#if __SIZEOF_INT__ < 4
#define int __INT32_TYPE__
#endif
/* For `&`, the non-negativeness of b is not taken into account. */
int f_and_gt(int len) {
len &= 0xfffff;
const int N = 4;
int newlen = len & -N;
return newlen > len; // return 0
}
int f_and_gt_(int len, int N) {
len &= 0xfffff;
int newlen = len & -N;
return newlen > len; // return 0
}
/* For `|`, to get a known value, b either needs to be non-negative
or a constant. For the negative constant case, we swap around the comparison. */
int f_or_lt_(int len, int N) {
len &= 0xfffff;
N &= 0xffff;
int newlen = len | N;
return newlen < len; // return 0
}
int f_or_ge(int len) {
len &= 0xfffff;
const int N = 4;
int newlen = len | -N;
return newlen >= len; // return 0
}
/* { dg-final { scan-tree-dump-not " > " "optimized" } } */
/* { dg-final { scan-tree-dump-not " < " "optimized" } } */
/* { dg-final { scan-tree-dump-not " & " "optimized" } } */
/* { dg-final { scan-tree-dump-not " \\\| " "optimized" } } */
/* { dg-final { scan-tree-dump-times "return 0;" 4 "optimized" } } */
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