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#ifndef __NPY_TYPED_COMMON_INC
#define __NPY_TYPED_COMMON_INC
/* utility functions that profit from templates */
#include "numpy/npy_common.h"
#include <assert.h>
/**begin repeat
* #name = int, uint, long, ulong,
* longlong, ulonglong#
* #type = npy_int, npy_uint, npy_long, npy_ulong,
* npy_longlong, npy_ulonglong#
* #MAX = NPY_MAX_INT, NPY_MAX_UINT, NPY_MAX_LONG, NPY_MAX_ULONG,
* NPY_MAX_LONGLONG, NPY_MAX_ULONGLONG#
*
* #neg = (1,0)*3#
* #abs_func = abs*2, labs*2, llabs*2#
*/
/*
* writes result of a * b into r
* returns 1 if a * b overflowed else returns 0
*
* These functions are not designed to work if either a or b is negative, but
* that is not checked. Could use absolute values and adjust the sign if that
* functionality was desired.
*/
static inline int
npy_mul_with_overflow_@name@(@type@ * r, @type@ a, @type@ b)
{
#ifdef HAVE___BUILTIN_MUL_OVERFLOW
return __builtin_mul_overflow(a, b, r);
#else
const @type@ half_sz = ((@type@)1 << ((sizeof(a) * 8 - 1 ) / 2));
*r = a * b;
/*
* avoid expensive division on common no overflow case
*/
if ((NPY_UNLIKELY((a | b) >= half_sz) || (a | b) < 0) &&
a != 0 &&
#if @neg@
@abs_func@(b) > @abs_func@(@MAX@ / a)
#else
b > @MAX@ / a
#endif
) {
return 1;
}
return 0;
#endif
}
/**end repeat**/
static inline int
npy_mul_sizes_with_overflow (npy_intp * r, npy_intp a, npy_intp b)
{
#ifdef HAVE___BUILTIN_MUL_OVERFLOW
return __builtin_mul_overflow(a, b, r);
#else
/* this function only supports non-negative numbers */
assert(a >= 0 && b >= 0);
const npy_intp half_sz = ((npy_intp)1 << ((sizeof(a) * 8 - 1 ) / 2));
*r = a * b;
/*
* avoid expensive division on common no overflow case
*/
if (NPY_UNLIKELY((a | b) >= half_sz)
&& a != 0 && b > NPY_MAX_INTP / a) {
return 1;
}
return 0;
#endif
}
#endif
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