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_floor.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 libm/src/s_floor.c (limited to 'libm/src/s_floor.c') diff --git a/libm/src/s_floor.c b/libm/src/s_floor.c new file mode 100644 index 0000000..b37c41b --- /dev/null +++ b/libm/src/s_floor.c @@ -0,0 +1,79 @@ + +/* @(#)s_floor.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. + * ==================================================== + */ + +/* + * floor(x) + * Return x rounded toward -inf to integral value + * Method: + * Bit twiddling. + * Exception: + * Inexact flag raised if x not equal to floor(x). + */ + +#include "fdlibm.h" + +#ifdef __STDC__ +static const double huge = 1.0e300; +#else +static double huge = 1.0e300; +#endif + +#ifdef __STDC__ + double floor(double x) +#else + double floor(x) + double x; +#endif +{ + int i0,i1,j0; + unsigned i,j; + i0 = __HI(x); + i1 = __LO(x); + j0 = ((i0>>20)&0x7ff)-0x3ff; + if(j0<20) { + if(j0<0) { /* raise inexact if x != 0 */ + if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */ + if(i0>=0) {i0=i1=0;} + else if(((i0&0x7fffffff)|i1)!=0) + { i0=0xbff00000;i1=0;} + } + } else { + i = (0x000fffff)>>j0; + if(((i0&i)|i1)==0) return x; /* x is integral */ + if(huge+x>0.0) { /* raise inexact flag */ + if(i0<0) i0 += (0x00100000)>>j0; + i0 &= (~i); i1=0; + } + } + } else if (j0>51) { + if(j0==0x400) return x+x; /* inf or NaN */ + else return x; /* x is integral */ + } else { + i = ((unsigned)(0xffffffff))>>(j0-20); + if((i1&i)==0) return x; /* x is integral */ + if(huge+x>0.0) { /* raise inexact flag */ + if(i0<0) { + if(j0==20) i0+=1; + else { + j = i1+(1<<(52-j0)); + if(j