mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-29 08:11:08 +00:00
54142c44e9
Where glibc code needs to avoid excess range and precision in floating-point arithmetic, code variously uses either asms or volatile to force the results of that arithmetic to memory; mostly this is conditional on FLT_EVAL_METHOD, but in the case of lrint / llrint functions some use of volatile is unconditional (and is present unnecessarily in versions for long double). This patch make such code use the recently-added math_narrow_eval macro consistently, removing the unnecessary uses of volatile in long double lrint / llrint implementations completely. Tested for x86_64, x86, mips64 and powerpc. * math/s_nexttowardf.c (__nexttowardf): Use math_narrow_eval. * stdlib/strtod_l.c: Include <math_private.h>. (overflow_value): Use math_narrow_eval. (underflow_value): Likewise. * sysdeps/i386/fpu/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/i386/fpu/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/dbl-64/e_gamma_r.c (gamma_positive): Likewise. (__ieee754_gamma_r): Likewise. * sysdeps/ieee754/dbl-64/gamma_productf.c (__gamma_productf): Likewise. * sysdeps/ieee754/dbl-64/k_rem_pio2.c (__kernel_rem_pio2): Likewise. * sysdeps/ieee754/dbl-64/lgamma_neg.c (__lgamma_neg): Likewise. * sysdeps/ieee754/dbl-64/s_erf.c (__erfc): Likewise. * sysdeps/ieee754/dbl-64/s_llrint.c (__llrint): Likewise. * sysdeps/ieee754/dbl-64/s_lrint.c (__lrint): Likewise. * sysdeps/ieee754/flt-32/e_gammaf_r.c (gammaf_positive): Likewise. (__ieee754_gammaf_r): Likewise. * sysdeps/ieee754/flt-32/k_rem_pio2f.c (__kernel_rem_pio2f): Likewise. * sysdeps/ieee754/flt-32/lgamma_negf.c (__lgamma_negf): Likewise. * sysdeps/ieee754/flt-32/s_erff.c (__erfcf): Likewise. * sysdeps/ieee754/flt-32/s_llrintf.c (__llrintf): Likewise. * sysdeps/ieee754/flt-32/s_lrintf.c (__lrintf): Likewise. * sysdeps/ieee754/ldbl-128/s_llrintl.c (__llrintl): Do not use volatile. * sysdeps/ieee754/ldbl-128/s_lrintl.c (__lrintl): Likewise. * sysdeps/ieee754/ldbl-128/s_nexttoward.c (__nexttoward): Use math_narrow_eval. * sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-96/gamma_product.c (__gamma_product): Likewise. * sysdeps/ieee754/ldbl-96/s_llrintl.c (__llrintl): Do not use volatile. * sysdeps/ieee754/ldbl-96/s_lrintl.c (__lrintl): Likewise. * sysdeps/ieee754/ldbl-96/s_nexttoward.c (__nexttoward): Use math_narrow_eval. * sysdeps/ieee754/ldbl-96/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c (__nldbl_nexttowardf): Likewise.
91 lines
2.3 KiB
C
91 lines
2.3 KiB
C
/* s_nexttoward.c
|
|
* Special i387 version
|
|
* Conversion from s_nextafter.c by Ulrich Drepper, Cygnus Support,
|
|
* drepper@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: $";
|
|
#endif
|
|
|
|
/* IEEE functions
|
|
* nexttoward(x,y)
|
|
* return the next machine floating-point number of x in the
|
|
* direction toward y.
|
|
* Special cases:
|
|
*/
|
|
|
|
#include <math.h>
|
|
#include <math_private.h>
|
|
#include <float.h>
|
|
|
|
double __nexttoward(double x, long double y)
|
|
{
|
|
int32_t hx,ix,iy;
|
|
u_int32_t lx,hy,ly,esy;
|
|
|
|
EXTRACT_WORDS(hx,lx,x);
|
|
GET_LDOUBLE_WORDS(esy,hy,ly,y);
|
|
ix = hx&0x7fffffff; /* |x| */
|
|
iy = esy&0x7fff; /* |y| */
|
|
|
|
/* Intel's extended format has the normally implicit 1 explicit
|
|
present. Sigh! */
|
|
if(((ix>=0x7ff00000)&&((ix-0x7ff00000)|lx)!=0) || /* x is nan */
|
|
((iy>=0x7fff)&&((hy&0x7fffffff)|ly)!=0)) /* y is nan */
|
|
return x+y;
|
|
if((long double) x==y) return y; /* x=y, return y */
|
|
if((ix|lx)==0) { /* x == 0 */
|
|
double u;
|
|
INSERT_WORDS(x,(esy&0x8000)<<16,1); /* return +-minsub */
|
|
u = math_opt_barrier (x);
|
|
u = u * u;
|
|
math_force_eval (u); /* raise underflow flag */
|
|
return x;
|
|
}
|
|
if(hx>=0) { /* x > 0 */
|
|
if (x > y) { /* x -= ulp */
|
|
if(lx==0) hx -= 1;
|
|
lx -= 1;
|
|
} else { /* x < y, x += ulp */
|
|
lx += 1;
|
|
if(lx==0) hx += 1;
|
|
}
|
|
} else { /* x < 0 */
|
|
if (x < y) { /* x -= ulp */
|
|
if(lx==0) hx -= 1;
|
|
lx -= 1;
|
|
} else { /* x > y, x += ulp */
|
|
lx += 1;
|
|
if(lx==0) hx += 1;
|
|
}
|
|
}
|
|
hy = hx&0x7ff00000;
|
|
if(hy>=0x7ff00000) {
|
|
x = math_narrow_eval (x+x); /* overflow */
|
|
return x;
|
|
}
|
|
if(hy<0x00100000) {
|
|
double u = x*x; /* underflow */
|
|
math_force_eval (u); /* raise underflow flag */
|
|
}
|
|
INSERT_WORDS(x,hx,lx);
|
|
return x;
|
|
}
|
|
weak_alias (__nexttoward, nexttoward)
|
|
#ifdef NO_LONG_DOUBLE
|
|
strong_alias (__nexttoward, __nexttowardl)
|
|
weak_alias (__nexttoward, nexttowardl)
|
|
#endif
|