87 lines
3.2 KiB
C
87 lines
3.2 KiB
C
/* $NetBSD: fixunsdfdi.c,v 1.11 2013/02/03 01:48:53 matt Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 1992, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This software was developed by the Computer Systems Engineering group
|
|
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
|
|
* contributed to Berkeley.
|
|
*
|
|
* 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.
|
|
* 3. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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)
|
|
#if 0
|
|
static char sccsid[] = "@(#)fixunsdfdi.c 8.1 (Berkeley) 6/4/93";
|
|
#else
|
|
__RCSID("$NetBSD: fixunsdfdi.c,v 1.11 2013/02/03 01:48:53 matt Exp $");
|
|
#endif
|
|
#endif /* LIBC_SCCS and not lint */
|
|
|
|
#if defined(SOFTFLOAT) || defined(__ARM_EABI__)
|
|
#include "softfloat/softfloat-for-gcc.h"
|
|
#endif
|
|
|
|
#include "quad.h"
|
|
|
|
#define ONE_FOURTH ((int)1 << (unsigned int)(INT_BITS - 2))
|
|
#define ONE_HALF (ONE_FOURTH * 2.0)
|
|
#define ONE (ONE_FOURTH * 4.0)
|
|
|
|
/*
|
|
* Convert double to (unsigned) quad.
|
|
* Not sure what to do with negative numbers---for now, anything out
|
|
* of range becomes UQUAD_MAX.
|
|
*/
|
|
u_quad_t
|
|
__fixunsdfdi(double x)
|
|
{
|
|
union uu t;
|
|
unsigned int tmp;
|
|
|
|
if (x < 0)
|
|
return (UQUAD_MAX); /* ??? should be 0? ERANGE??? */
|
|
#ifdef notdef /* this falls afoul of a GCC bug */
|
|
if (x >= UQUAD_MAX)
|
|
return (UQUAD_MAX);
|
|
#else /* so we wire in 2^64-1 instead */
|
|
if (x >= 18446744073709551615.0) /* XXX */
|
|
return (UQUAD_MAX);
|
|
#endif
|
|
/*
|
|
* Now we know that 0 <= x <= 18446744073709549568. The upper
|
|
* limit is one ulp less than 18446744073709551615 tested for above.
|
|
* Dividing this by 2^32 will *not* round irrespective of any
|
|
* rounding modes (except if the result is an IEEE denorm).
|
|
* Furthermore, the quotient will fit into a 32-bit integer.
|
|
*/
|
|
tmp = x / ONE;
|
|
t.ul[L] = (unsigned int) (x - tmp * ONE);
|
|
t.ul[H] = tmp;
|
|
return (t.uq);
|
|
}
|