freebsd-nq/lib/libc/quad/fixunsdfdi.c
Dimitry Andric feb1d5507e Add casts and L suffixes to libc quad support, to work around various
-Werror warnings from clang 10.0.0, such as:

lib/libc/quad/fixdfdi.c:57:12: error: implicit conversion from 'long long' to 'double' changes value from 9223372036854775807 to 9223372036854775808 [-Werror,-Wimplicit-int-float-conversion]
                if (x >= QUAD_MAX)
                      ~~ ^~~~~~~~
/usr/obj/usr/src/powerpc.powerpc/tmp/usr/include/sys/limits.h:89:19: note: expanded from macro 'QUAD_MAX'
#define QUAD_MAX        (__QUAD_MAX)    /* max value for a quad_t */
                         ^~~~~~~~~~
/usr/obj/usr/src/powerpc.powerpc/tmp/usr/include/machine/_limits.h:91:20: note: expanded from macro '__QUAD_MAX'
#define __QUAD_MAX      __LLONG_MAX     /* max value for a quad_t */
                        ^~~~~~~~~~~
/usr/obj/usr/src/powerpc.powerpc/tmp/usr/include/machine/_limits.h:75:21: note: expanded from macro '__LLONG_MAX'
#define __LLONG_MAX     0x7fffffffffffffffLL    /* max value for a long long */
                        ^~~~~~~~~~~~~~~~~~~~

and many instances of:

lib/libc/quad/fixunsdfdi.c:73:17: error: shift count >= width of type [-Werror,-Wshift-count-overflow]
        toppart = (x - ONE_HALF) / ONE;
                       ^~~~~~~~
lib/libc/quad/fixunsdfdi.c:45:19: note: expanded from macro 'ONE_HALF'
#define ONE_HALF        (ONE_FOURTH * 2.0)
                         ^~~~~~~~~~
lib/libc/quad/fixunsdfdi.c:44:23: note: expanded from macro 'ONE_FOURTH'
#define ONE_FOURTH      (1 << (LONG_BITS - 2))
                           ^  ~~~~~~~~~~~~~~~
lib/libc/quad/fixunsdfdi.c:73:29: error: shift count >= width of type [-Werror,-Wshift-count-overflow]
        toppart = (x - ONE_HALF) / ONE;
                                   ^~~
lib/libc/quad/fixunsdfdi.c:46:15: note: expanded from macro 'ONE'
#define ONE             (ONE_FOURTH * 4.0)
                         ^~~~~~~~~~
lib/libc/quad/fixunsdfdi.c:44:23: note: expanded from macro 'ONE_FOURTH'
#define ONE_FOURTH      (1 << (LONG_BITS - 2))
                           ^  ~~~~~~~~~~~~~~~
2020-02-17 20:14:59 +00:00

96 lines
3.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)fixunsdfdi.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "quad.h"
#define ONE_FOURTH (1L << (LONG_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)
{
double toppart;
union uu t;
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)
return (UQUAD_MAX);
#endif
/*
* Get the upper part of the result. Note that the divide
* may round up; we want to avoid this if possible, so we
* subtract `1/2' first.
*/
toppart = (x - ONE_HALF) / ONE;
/*
* Now build a u_quad_t out of the top part. The difference
* between x and this is the bottom part (this may introduce
* a few fuzzy bits, but what the heck). With any luck this
* difference will be nonnegative: x should wind up in the
* range [0..ULONG_MAX]. For paranoia, we assume [LONG_MIN..
* 2*ULONG_MAX] instead.
*/
t.ul[H] = (unsigned long)toppart;
t.ul[L] = 0;
x -= (double)t.uq;
if (x < 0) {
t.ul[H]--;
x += (double)ULONG_MAX;
}
if (x > (double)ULONG_MAX) {
t.ul[H]++;
x -= (double)ULONG_MAX;
}
t.ul[L] = (u_long)x;
return (t.uq);
}