minix/lib/libc/gen/fixunsdfsi_ieee754.c

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/* $NetBSD: fixunsdfsi_ieee754.c,v 1.3 2013/04/30 01:44:07 matt Exp $ */
/*-
* Copyright (c) 2011 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Matt Thomas of 3am Software Foundry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: fixunsdfsi_ieee754.c,v 1.3 2013/04/30 01:44:07 matt Exp $");
#endif /* LIBC_SCCS and not lint */
#include <stdbool.h>
#include <stdint.h>
#include <float.h>
#include <machine/ieee.h>
#if defined(SOFTFLOAT) || defined(__ARM_EABI__)
#include "softfloat/softfloat-for-gcc.h"
#endif
uint32_t __fixunsgen32(int, bool, size_t, size_t, const uint32_t *);
uint32_t __fixunsdfsi(double);
/*
* Convert double to (unsigned) int. All operations are done module 2^32.
*/
uint32_t
__fixunsdfsi(double x)
{
const union ieee_double_u dblu = { .dblu_d = x };
const uint32_t frac[(DBL_FRACBITS + 31)/32 + 1] = {
[0] = 0,
[1] = dblu.dblu_dbl.dbl_fracl,
[2] = dblu.dblu_dbl.dbl_frach,
};
return __fixunsgen32(
dblu.dblu_dbl.dbl_exp - DBL_EXP_BIAS,
dblu.dblu_dbl.dbl_sign != 0,
DBL_MANT_DIG,
DBL_FRACHBITS,
&frac[__arraycount(frac)-1]);
}