freebsd-dev/lib/libc/ia64/_fpmath.h
David Schultz 21f9dd806f - Define LDBL_NBIT to be a mask indicating the position of the integer
bit in a long double.  For architectures that don't have such a bit,
  LDBL_NBIT is 0.  This makes it possible to say `mantissa & ~LDBL_NBIT'
  in places that previously used an #ifdef to select the right expression.
  The optimizer should dispense with the extra arithmetic when LDBL_NBIT
  is 0 anyway.
- Add an XXX comment for the big endian case.
2005-03-07 04:55:40 +00:00

72 lines
2.4 KiB
C

/*-
* Copyright (c) 2003 Mike Barcroft <mike@FreeBSD.org>
* Copyright (c) 2002, 2003 David Schultz <das@FreeBSD.ORG>
* All rights reserved.
*
* 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 AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#include <sys/endian.h>
union IEEEl2bits {
long double e;
struct {
#if _BYTE_ORDER == _LITTLE_ENDIAN
unsigned int manl :32;
unsigned int manh :32;
unsigned int exp :15;
unsigned int sign :1;
unsigned long junk :48;
#else /* _BIG_ENDIAN */
unsigned long junk :48;
unsigned int sign :1;
unsigned int exp :15;
unsigned int manh :32;
unsigned int manl :32;
#endif
} bits;
};
#if _BYTE_ORDER == _LITTLE_ENDIAN
#define LDBL_NBIT 0x80000000
#define mask_nbit_l(u) ((u).bits.manh &= ~LDBL_NBIT)
#else /* _BIG_ENDIAN */
/*
* XXX This doesn't look right. Very few machines have a different
* endianness for integers and floating-point, and in nextafterl()
* we assume that none do. If you have an environment for testing
* this, please let me know. --das
*/
#define LDBL_NBIT 0x80
#define mask_nbit_l(u) ((u).bits.manh &= ~LDBL_NBIT)
#endif
#define LDBL_MANH_SIZE 32
#define LDBL_MANL_SIZE 32
#define LDBL_TO_ARRAY32(u, a) do { \
(a)[0] = (uint32_t)(u).bits.manl; \
(a)[1] = (uint32_t)(u).bits.manh; \
} while(0)