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/*
* Copyright (c) 2025 Robert Clausecker <fuz@FreeBSD.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <assert.h>
#include <limits.h>
#include <stdbit.h>
/* Ensure we do not shift 1U out of range. */
static_assert(UCHAR_WIDTH < UINT_WIDTH,
"stdc_trailing_zeros_uc needs UCHAR_WIDTH < UINT_WIDTH");
unsigned int
stdc_trailing_zeros_uc(unsigned char x)
{
return (__builtin_ctz(x | 1U << UCHAR_WIDTH));
}
/* Ensure we do not shift 1U out of range. */
static_assert(USHRT_WIDTH < UINT_WIDTH,
"stdc_trailing_zeros_uc needs USHRT_WIDTH < UINT_WIDTH");
unsigned int
stdc_trailing_zeros_us(unsigned short x)
{
return (__builtin_ctz(x | 1U << USHRT_WIDTH));
}
unsigned int
stdc_trailing_zeros_ui(unsigned int x)
{
if (x == 0U)
return (UINT_WIDTH);
return (__builtin_ctz(x));
}
unsigned int
stdc_trailing_zeros_ul(unsigned long x)
{
if (x == 0UL)
return (ULONG_WIDTH);
return (__builtin_ctzl(x));
}
unsigned int
stdc_trailing_zeros_ull(unsigned long long x)
{
if (x == 0ULL)
return (ULLONG_WIDTH);
return (__builtin_ctzll(x));
}
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