glibc/sysdeps/ieee754/flt-32/s_finitef.c
Joseph Myers b8682397ab Reduce number of constants in __finite* (bug 15384).
Bug 15384 notes that in __finite, two different constants are used
that could be the same constant (the result only depends on the
exponent of the floating-point representation), and that using the
same constant is better for architectures where constants need loading
from a constant pool.  This patch implements that change.

Tested for x86_64, mips64 and powerpc.

	[BZ #15384]
	* sysdeps/ieee754/dbl-64/s_finite.c (FINITE): Use same constant as
	bit-mask as in subtraction.
	* sysdeps/ieee754/dbl-64/wordsize-64/s_finite.c (__finite):
	Likewise.
	* sysdeps/ieee754/flt-32/s_finitef.c (FINITEF): Likewise.
	* sysdeps/ieee754/ldbl-128/s_finitel.c (__finitel): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_finitel.c (__finitel): Likewise.
2015-09-17 16:47:14 +00:00

42 lines
1003 B
C

/* s_finitef.c -- float version of s_finite.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: s_finitef.c,v 1.4 1995/05/10 20:47:18 jtc Exp $";
#endif
/*
* finitef(x) returns 1 is x is finite, else 0;
* no branching!
*/
#include <math.h>
#include <math_private.h>
#undef __finitef
#ifndef FINITEF
# define FINITEF __finitef
#endif
int FINITEF(float x)
{
int32_t ix;
GET_FLOAT_WORD(ix,x);
return (int)((u_int32_t)((ix&0x7f800000)-0x7f800000)>>31);
}
hidden_def (__finitef)
weak_alias (__finitef, finitef)