glibc/sysdeps/ieee754/flt-32/s_log1pf.c

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/* s_log1pf.c -- float version of s_log1p.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
Update. 1997-07-22 01:35 Ulrich Drepper <drepper@cygnus.com> * Makerules (+make-deps): Use $(CFLAGS) in run of $(+mkdep) so that optimizing is also selected for dependency generation. * configure.in: Add machine description for TI c[34]x. * inet/Makefile (routines): Remove ntohl and ntohs. * inet/netinet/in.h: Use optimized version of hton? and ntoh? for little endian machines. * sysdeps/alpha/ntohl.s: Removed. * sysdeps/alpha/ntohs.s: Removed. * sysdeps/generic/ntohl.c: Removed. * sysdeps/generic/ntohs.c: Removed. * sysdeps/generic/htonl.c: Add aliases for ntohl. * sysdeps/vax/htonl.s: Likewise. * sysdeps/generic/htons.c: Add aliases for ntohs. * sysdeps/vax/htons.s: Likewise. * sysdeps/vax/ntohl.s: Removed. * sysdeps/vax/ntohs.s: Removed. * sysdeps/generic/bits/htontoh.h: New file. * sysdeps/i386/htonl.S: New file. * sysdeps/i386/htons.S: New file. * sysdeps/i386/i486/htonl.S: New file. * sysdeps/i386/fpu/bits/mathinline.h: Correct and optimized compare macros. * sysdeps/mips/dl-machine.h: Remove mips64 dependent parts. * sysdeps/mips/mips64/dl-machine.h: New file. * sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Don't install syscall-list.h. 1997-07-12 Andreas Jaeger <aj@arthur.rhein-neckar.de> * libc.map: Add missing symbol _obstack. 1997-07-14 08:22 H.J. Lu <hjl@gnu.ai.mit.edu> * sysdeps/mips/rtld-parms: New. * sysdeps/unix/sysv/linux/mips/lxstat.h: Moved to * sysdeps/unix/sysv/linux/mips/lxstat.c: ...this. * sysdeps/unix/sysv/linux/mips/sgidef.h: Moved to * sysdeps/unix/sysv/linux/mips/sgidefs.h: ...this. * sysdeps/generic/dl-sysdep.c (_start): Change to ENTRY_POINT. 1997-07-17 08:39 H.J. Lu <hjl@gnu.ai.mit.edu> * sysdeps/mips/dl-machine.h: Remove extra stuff. 1997-07-06 07:18 Geoff Keating <geoffk@ozemail.com.au> * sysdeps/powerpc/bits/endian.h: Handle multiple endianess. * stdlib/grouping.h: Suppress gcc warning about testing unsigned char for less-than-zero. * stdio-common/printf_fp.c: Likewise. * stdio-common/vfprintf.c: Likewise. * sysdeps/powerpc/add_n.s: New file. * sysdeps/powerpc/sub_n.s: New file. * sysdeps/powerpc/lshift.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/mul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/addmul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/submul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/rshift.s: Ported XCOFF->ELF (from GMP). * math/libm-test.c (cos_test, sin_test, sincos_test): Use precomputed pi/6 rather than having gcc calculate it, otherwise tests give inaccurate result due to inaccurate input. * math/libm.map: Add __fe_*_env constants to list of exported symbols. * sysdeps/libm-ieee754/s_isinf.c: Simplify, make faster. * sysdeps/libm-ieee754/s_isinff.c: Simplify, make faster. * sysdeps/libm-ieee754/s_atan2f.c: Correct value of pi to be correct round-to-nearest value. * sysdeps/libm-ieee754/e_log.c: Make sure exceptions are raised. * sysdeps/libm-ieee754/e_log10.c: Likewise. * sysdeps/libm-ieee754/e_log10f.c: Likewise. * sysdeps/libm-ieee754/e_logf.c: Likewise. * sysdeps/libm-ieee754/s_log1p.c: Likewise. Also use correct -Inf. * sysdeps/libm-ieee754/s_log1pf.c: Likewise. Also use correct -Inf. * sysdeps/libm-ieee754/s_log2.c: Likewise. * sysdeps/libm-ieee754/s_log2f.c: Likewise. 1997-07-15 21:54 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> * nis/nss_compat/compat-grp.c: Fix "buffer to small" problems and memory leaks. * nis/nss_compat/compat-pwd.c: Likewise. * nis/nss_compat/compat-spwd.c: Likewise. * nis/nss_nis/nis-alias.c: Likewise. * nis/nss_nis/nis-ethers.c: Likewise. * nis/nss_nis/nis-grp.c: Likewise. * nis/nss_nis/nis-hosts.c: Likewise. * nis/nss_nis/nis-network.c: Likewise. * nis/nss_nis/nis-proto.c: Likewise. * nis/nss_nis/nis-pwd.c: Likewise. * nis/nss_nis/nis-rpc.c: Likewise. * nis/nss_nis/nis-service.c: Likewise. * nis/nss_nis/nis-spwd.c: Likewise. * nis/nss_nisplus-alias.c: Likewise. * nis/nss_nisplus-ethers.c: Likewise. * nis/nss_nisplus-grp.c: Likewise. * nis/nss_nisplus-hosts.c: Likewise. * nis/nss_nisplus-netgrp.c: Likewise. * nis/nss_nisplus-network.c: Likewise. * nis/nss_nisplus-proto.c: Likewise. * nis/nss_nisplus-pwd.c: Likewise. * nis/nss_nisplus-rpc.c: Likewise. * nis/nss_nisplus-service.c: Likewise. * nis/nss_nisplus-spwd.c: Likewise. * nis/nss_nisplus-parse.c: If buffer to small, give -1 back. 1997-07-20 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/m68k/dl-machine.h (elf_machine_rela): Mention program name in warning message. * sysdeps/powerpc/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_rel): Print program name first. 1997-07-20 19:33 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> * libc.map: Add _null_auth and _seterr_reply. * sunrpc/clnt_udp.c (clntudp_call): If xargs is NULL, don't encode it.
1997-07-22 00:10:33 +00:00
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include <float.h>
#include <math.h>
#include <math_private.h>
static const float
ln2_hi = 6.9313812256e-01, /* 0x3f317180 */
ln2_lo = 9.0580006145e-06, /* 0x3717f7d1 */
two25 = 3.355443200e+07, /* 0x4c000000 */
Lp1 = 6.6666668653e-01, /* 3F2AAAAB */
Lp2 = 4.0000000596e-01, /* 3ECCCCCD */
Lp3 = 2.8571429849e-01, /* 3E924925 */
Lp4 = 2.2222198546e-01, /* 3E638E29 */
Lp5 = 1.8183572590e-01, /* 3E3A3325 */
Lp6 = 1.5313838422e-01, /* 3E1CD04F */
Lp7 = 1.4798198640e-01; /* 3E178897 */
static const float zero = 0.0;
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float
__log1pf(float x)
{
float hfsq,f,c,s,z,R,u;
int32_t k,hx,hu,ax;
GET_FLOAT_WORD(hx,x);
ax = hx&0x7fffffff;
k = 1;
if (hx < 0x3ed413d7) { /* x < 0.41422 */
if(ax>=0x3f800000) { /* x <= -1.0 */
if(x==(float)-1.0) return -two25/zero; /* log1p(-1)=-inf */
else return (x-x)/(x-x); /* log1p(x<-1)=NaN */
}
if(ax<0x31000000) { /* |x| < 2**-29 */
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math_force_eval(two25+x); /* raise inexact */
if (ax<0x24800000) /* |x| < 2**-54 */
{
if (fabsf (x) < FLT_MIN)
{
float force_underflow = x * x;
math_force_eval (force_underflow);
}
return x;
}
else
return x - x*x*(float)0.5;
}
if(hx>0||hx<=((int32_t)0xbe95f61f)) {
k=0;f=x;hu=1;} /* -0.2929<x<0.41422 */
Update. 1997-07-22 01:35 Ulrich Drepper <drepper@cygnus.com> * Makerules (+make-deps): Use $(CFLAGS) in run of $(+mkdep) so that optimizing is also selected for dependency generation. * configure.in: Add machine description for TI c[34]x. * inet/Makefile (routines): Remove ntohl and ntohs. * inet/netinet/in.h: Use optimized version of hton? and ntoh? for little endian machines. * sysdeps/alpha/ntohl.s: Removed. * sysdeps/alpha/ntohs.s: Removed. * sysdeps/generic/ntohl.c: Removed. * sysdeps/generic/ntohs.c: Removed. * sysdeps/generic/htonl.c: Add aliases for ntohl. * sysdeps/vax/htonl.s: Likewise. * sysdeps/generic/htons.c: Add aliases for ntohs. * sysdeps/vax/htons.s: Likewise. * sysdeps/vax/ntohl.s: Removed. * sysdeps/vax/ntohs.s: Removed. * sysdeps/generic/bits/htontoh.h: New file. * sysdeps/i386/htonl.S: New file. * sysdeps/i386/htons.S: New file. * sysdeps/i386/i486/htonl.S: New file. * sysdeps/i386/fpu/bits/mathinline.h: Correct and optimized compare macros. * sysdeps/mips/dl-machine.h: Remove mips64 dependent parts. * sysdeps/mips/mips64/dl-machine.h: New file. * sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Don't install syscall-list.h. 1997-07-12 Andreas Jaeger <aj@arthur.rhein-neckar.de> * libc.map: Add missing symbol _obstack. 1997-07-14 08:22 H.J. Lu <hjl@gnu.ai.mit.edu> * sysdeps/mips/rtld-parms: New. * sysdeps/unix/sysv/linux/mips/lxstat.h: Moved to * sysdeps/unix/sysv/linux/mips/lxstat.c: ...this. * sysdeps/unix/sysv/linux/mips/sgidef.h: Moved to * sysdeps/unix/sysv/linux/mips/sgidefs.h: ...this. * sysdeps/generic/dl-sysdep.c (_start): Change to ENTRY_POINT. 1997-07-17 08:39 H.J. Lu <hjl@gnu.ai.mit.edu> * sysdeps/mips/dl-machine.h: Remove extra stuff. 1997-07-06 07:18 Geoff Keating <geoffk@ozemail.com.au> * sysdeps/powerpc/bits/endian.h: Handle multiple endianess. * stdlib/grouping.h: Suppress gcc warning about testing unsigned char for less-than-zero. * stdio-common/printf_fp.c: Likewise. * stdio-common/vfprintf.c: Likewise. * sysdeps/powerpc/add_n.s: New file. * sysdeps/powerpc/sub_n.s: New file. * sysdeps/powerpc/lshift.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/mul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/addmul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/submul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/rshift.s: Ported XCOFF->ELF (from GMP). * math/libm-test.c (cos_test, sin_test, sincos_test): Use precomputed pi/6 rather than having gcc calculate it, otherwise tests give inaccurate result due to inaccurate input. * math/libm.map: Add __fe_*_env constants to list of exported symbols. * sysdeps/libm-ieee754/s_isinf.c: Simplify, make faster. * sysdeps/libm-ieee754/s_isinff.c: Simplify, make faster. * sysdeps/libm-ieee754/s_atan2f.c: Correct value of pi to be correct round-to-nearest value. * sysdeps/libm-ieee754/e_log.c: Make sure exceptions are raised. * sysdeps/libm-ieee754/e_log10.c: Likewise. * sysdeps/libm-ieee754/e_log10f.c: Likewise. * sysdeps/libm-ieee754/e_logf.c: Likewise. * sysdeps/libm-ieee754/s_log1p.c: Likewise. Also use correct -Inf. * sysdeps/libm-ieee754/s_log1pf.c: Likewise. Also use correct -Inf. * sysdeps/libm-ieee754/s_log2.c: Likewise. * sysdeps/libm-ieee754/s_log2f.c: Likewise. 1997-07-15 21:54 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> * nis/nss_compat/compat-grp.c: Fix "buffer to small" problems and memory leaks. * nis/nss_compat/compat-pwd.c: Likewise. * nis/nss_compat/compat-spwd.c: Likewise. * nis/nss_nis/nis-alias.c: Likewise. * nis/nss_nis/nis-ethers.c: Likewise. * nis/nss_nis/nis-grp.c: Likewise. * nis/nss_nis/nis-hosts.c: Likewise. * nis/nss_nis/nis-network.c: Likewise. * nis/nss_nis/nis-proto.c: Likewise. * nis/nss_nis/nis-pwd.c: Likewise. * nis/nss_nis/nis-rpc.c: Likewise. * nis/nss_nis/nis-service.c: Likewise. * nis/nss_nis/nis-spwd.c: Likewise. * nis/nss_nisplus-alias.c: Likewise. * nis/nss_nisplus-ethers.c: Likewise. * nis/nss_nisplus-grp.c: Likewise. * nis/nss_nisplus-hosts.c: Likewise. * nis/nss_nisplus-netgrp.c: Likewise. * nis/nss_nisplus-network.c: Likewise. * nis/nss_nisplus-proto.c: Likewise. * nis/nss_nisplus-pwd.c: Likewise. * nis/nss_nisplus-rpc.c: Likewise. * nis/nss_nisplus-service.c: Likewise. * nis/nss_nisplus-spwd.c: Likewise. * nis/nss_nisplus-parse.c: If buffer to small, give -1 back. 1997-07-20 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/m68k/dl-machine.h (elf_machine_rela): Mention program name in warning message. * sysdeps/powerpc/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_rel): Print program name first. 1997-07-20 19:33 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> * libc.map: Add _null_auth and _seterr_reply. * sunrpc/clnt_udp.c (clntudp_call): If xargs is NULL, don't encode it.
1997-07-22 00:10:33 +00:00
}
if (hx >= 0x7f800000) return x+x;
if(k!=0) {
if(hx<0x5a000000) {
Update. 1997-07-22 01:35 Ulrich Drepper <drepper@cygnus.com> * Makerules (+make-deps): Use $(CFLAGS) in run of $(+mkdep) so that optimizing is also selected for dependency generation. * configure.in: Add machine description for TI c[34]x. * inet/Makefile (routines): Remove ntohl and ntohs. * inet/netinet/in.h: Use optimized version of hton? and ntoh? for little endian machines. * sysdeps/alpha/ntohl.s: Removed. * sysdeps/alpha/ntohs.s: Removed. * sysdeps/generic/ntohl.c: Removed. * sysdeps/generic/ntohs.c: Removed. * sysdeps/generic/htonl.c: Add aliases for ntohl. * sysdeps/vax/htonl.s: Likewise. * sysdeps/generic/htons.c: Add aliases for ntohs. * sysdeps/vax/htons.s: Likewise. * sysdeps/vax/ntohl.s: Removed. * sysdeps/vax/ntohs.s: Removed. * sysdeps/generic/bits/htontoh.h: New file. * sysdeps/i386/htonl.S: New file. * sysdeps/i386/htons.S: New file. * sysdeps/i386/i486/htonl.S: New file. * sysdeps/i386/fpu/bits/mathinline.h: Correct and optimized compare macros. * sysdeps/mips/dl-machine.h: Remove mips64 dependent parts. * sysdeps/mips/mips64/dl-machine.h: New file. * sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Don't install syscall-list.h. 1997-07-12 Andreas Jaeger <aj@arthur.rhein-neckar.de> * libc.map: Add missing symbol _obstack. 1997-07-14 08:22 H.J. Lu <hjl@gnu.ai.mit.edu> * sysdeps/mips/rtld-parms: New. * sysdeps/unix/sysv/linux/mips/lxstat.h: Moved to * sysdeps/unix/sysv/linux/mips/lxstat.c: ...this. * sysdeps/unix/sysv/linux/mips/sgidef.h: Moved to * sysdeps/unix/sysv/linux/mips/sgidefs.h: ...this. * sysdeps/generic/dl-sysdep.c (_start): Change to ENTRY_POINT. 1997-07-17 08:39 H.J. Lu <hjl@gnu.ai.mit.edu> * sysdeps/mips/dl-machine.h: Remove extra stuff. 1997-07-06 07:18 Geoff Keating <geoffk@ozemail.com.au> * sysdeps/powerpc/bits/endian.h: Handle multiple endianess. * stdlib/grouping.h: Suppress gcc warning about testing unsigned char for less-than-zero. * stdio-common/printf_fp.c: Likewise. * stdio-common/vfprintf.c: Likewise. * sysdeps/powerpc/add_n.s: New file. * sysdeps/powerpc/sub_n.s: New file. * sysdeps/powerpc/lshift.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/mul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/addmul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/submul_1.s: Ported XCOFF->ELF (from GMP). * sysdeps/powerpc/rshift.s: Ported XCOFF->ELF (from GMP). * math/libm-test.c (cos_test, sin_test, sincos_test): Use precomputed pi/6 rather than having gcc calculate it, otherwise tests give inaccurate result due to inaccurate input. * math/libm.map: Add __fe_*_env constants to list of exported symbols. * sysdeps/libm-ieee754/s_isinf.c: Simplify, make faster. * sysdeps/libm-ieee754/s_isinff.c: Simplify, make faster. * sysdeps/libm-ieee754/s_atan2f.c: Correct value of pi to be correct round-to-nearest value. * sysdeps/libm-ieee754/e_log.c: Make sure exceptions are raised. * sysdeps/libm-ieee754/e_log10.c: Likewise. * sysdeps/libm-ieee754/e_log10f.c: Likewise. * sysdeps/libm-ieee754/e_logf.c: Likewise. * sysdeps/libm-ieee754/s_log1p.c: Likewise. Also use correct -Inf. * sysdeps/libm-ieee754/s_log1pf.c: Likewise. Also use correct -Inf. * sysdeps/libm-ieee754/s_log2.c: Likewise. * sysdeps/libm-ieee754/s_log2f.c: Likewise. 1997-07-15 21:54 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> * nis/nss_compat/compat-grp.c: Fix "buffer to small" problems and memory leaks. * nis/nss_compat/compat-pwd.c: Likewise. * nis/nss_compat/compat-spwd.c: Likewise. * nis/nss_nis/nis-alias.c: Likewise. * nis/nss_nis/nis-ethers.c: Likewise. * nis/nss_nis/nis-grp.c: Likewise. * nis/nss_nis/nis-hosts.c: Likewise. * nis/nss_nis/nis-network.c: Likewise. * nis/nss_nis/nis-proto.c: Likewise. * nis/nss_nis/nis-pwd.c: Likewise. * nis/nss_nis/nis-rpc.c: Likewise. * nis/nss_nis/nis-service.c: Likewise. * nis/nss_nis/nis-spwd.c: Likewise. * nis/nss_nisplus-alias.c: Likewise. * nis/nss_nisplus-ethers.c: Likewise. * nis/nss_nisplus-grp.c: Likewise. * nis/nss_nisplus-hosts.c: Likewise. * nis/nss_nisplus-netgrp.c: Likewise. * nis/nss_nisplus-network.c: Likewise. * nis/nss_nisplus-proto.c: Likewise. * nis/nss_nisplus-pwd.c: Likewise. * nis/nss_nisplus-rpc.c: Likewise. * nis/nss_nisplus-service.c: Likewise. * nis/nss_nisplus-spwd.c: Likewise. * nis/nss_nisplus-parse.c: If buffer to small, give -1 back. 1997-07-20 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/m68k/dl-machine.h (elf_machine_rela): Mention program name in warning message. * sysdeps/powerpc/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_rel): Print program name first. 1997-07-20 19:33 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> * libc.map: Add _null_auth and _seterr_reply. * sunrpc/clnt_udp.c (clntudp_call): If xargs is NULL, don't encode it.
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u = (float)1.0+x;
GET_FLOAT_WORD(hu,u);
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k = (hu>>23)-127;
/* correction term */
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c = (k>0)? (float)1.0-(u-x):x-(u-(float)1.0);
c /= u;
} else {
u = x;
GET_FLOAT_WORD(hu,u);
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k = (hu>>23)-127;
c = 0;
}
hu &= 0x007fffff;
if(hu<0x3504f7) {
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SET_FLOAT_WORD(u,hu|0x3f800000);/* normalize u */
} else {
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k += 1;
SET_FLOAT_WORD(u,hu|0x3f000000); /* normalize u/2 */
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hu = (0x00800000-hu)>>2;
}
f = u-(float)1.0;
}
hfsq=(float)0.5*f*f;
if(hu==0) { /* |f| < 2**-20 */
if(f==zero) {
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if(k==0) return zero;
else {c += k*ln2_lo; return k*ln2_hi+c;}
}
R = hfsq*((float)1.0-(float)0.66666666666666666*f);
if(k==0) return f-R; else
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return k*ln2_hi-((R-(k*ln2_lo+c))-f);
}
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s = f/((float)2.0+f);
z = s*s;
R = z*(Lp1+z*(Lp2+z*(Lp3+z*(Lp4+z*(Lp5+z*(Lp6+z*Lp7))))));
if(k==0) return f-(hfsq-s*(hfsq+R)); else
return k*ln2_hi-((hfsq-(s*(hfsq+R)+(k*ln2_lo+c)))-f);
}