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/* PR tree-optimization/114760 */
/* { dg-do compile } */
/* { dg-require-effective-target clz } */
/* { dg-require-effective-target ctz } */
/* { dg-options "-O3 -fdump-tree-optimized" } */
unsigned
ntz32_1 (unsigned x)
{
int n = 32;
while (x != 0)
{
n = n - 1;
x = x * 2;
}
return n;
}
unsigned
ntz32_2 (unsigned x)
{
int n = 32;
while (x != 0)
{
n = n - 1;
x = x + x;
}
return n;
}
unsigned
ntz32_3 (unsigned x)
{
int n = 32;
while (x != 0)
{
n = n - 1;
x = x << 1;
}
return n;
}
#define PREC (__CHAR_BIT__ * __SIZEOF_INT__)
int
nlz32_1 (unsigned int b) {
int c = PREC;
while (b != 0) {
b >>= 1;
c --;
}
return c;
}
int
nlz32_2 (unsigned int b) {
int c = PREC;
while (b != 0) {
b /= 2;
c --;
}
return c;
}
/* { dg-final { scan-tree-dump-times "__builtin_ctz|\\.CTZ" 3 "optimized" } } */
/* { dg-final { scan-tree-dump-times "__builtin_clz|\\.CLZ" 2 "optimized" } } */
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