From 8b1fadd6a89f12cbc81c5d621a75b91dd9eedec2 Mon Sep 17 00:00:00 2001 From: Pixel Date: Sat, 5 Feb 2011 11:06:07 -0800 Subject: Adding Sun's fdlibm, and libnix's scanf, tweaked to become an xscanf. Adding a few more libc inlined also. --- libm/src/s_nextafter.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) create mode 100644 libm/src/s_nextafter.c (limited to 'libm/src/s_nextafter.c') diff --git a/libm/src/s_nextafter.c b/libm/src/s_nextafter.c new file mode 100644 index 0000000..c530952 --- /dev/null +++ b/libm/src/s_nextafter.c @@ -0,0 +1,78 @@ + +/* @(#)s_nextafter.c 1.3 95/01/18 */ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunSoft, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +/* IEEE functions + * nextafter(x,y) + * return the next machine floating-point number of x in the + * direction toward y. + * Special cases: + */ + +#include "fdlibm.h" + +#ifdef __STDC__ + double nextafter(double x, double y) +#else + double nextafter(x,y) + double x,y; +#endif +{ + int hx,hy,ix,iy; + unsigned lx,ly; + + hx = __HI(x); /* high word of x */ + lx = __LO(x); /* low word of x */ + hy = __HI(y); /* high word of y */ + ly = __LO(y); /* low word of y */ + ix = hx&0x7fffffff; /* |x| */ + iy = hy&0x7fffffff; /* |y| */ + + if(((ix>=0x7ff00000)&&((ix-0x7ff00000)|lx)!=0) || /* x is nan */ + ((iy>=0x7ff00000)&&((iy-0x7ff00000)|ly)!=0)) /* y is nan */ + return x+y; + if(x==y) return x; /* x=y, return x */ + if((ix|lx)==0) { /* x == 0 */ + __HI(x) = hy&0x80000000; /* return +-minsubnormal */ + __LO(x) = 1; + y = x*x; + if(y==x) return y; else return x; /* raise underflow flag */ + } + if(hx>=0) { /* x > 0 */ + if(hx>hy||((hx==hy)&&(lx>ly))) { /* 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(hy>=0||hx>hy||((hx==hy)&&(lx>ly))){/* 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) return x+x; /* overflow */ + if(hy<0x00100000) { /* underflow */ + y = x*x; + if(y!=x) { /* raise underflow flag */ + __HI(y) = hx; __LO(y) = lx; + return y; + } + } + __HI(x) = hx; __LO(x) = lx; + return x; +} -- cgit v1.2.3