| /* sf_floor.c -- float version of s_floor.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. |
| * ==================================================== |
| */ |
| |
| /* |
| * floorf(x) |
| * Return x rounded toward -inf to integral value |
| * Method: |
| * Bit twiddling. |
| * Exception: |
| * Inexact flag raised if x not equal to floorf(x). |
| */ |
| |
| #include "fdlibm.h" |
| |
| #ifdef __STDC__ |
| static const float huge = 1.0e30; |
| #else |
| static float huge = 1.0e30; |
| #endif |
| |
| #ifdef __STDC__ |
| float floorf(float x) |
| #else |
| float floorf(x) |
| float x; |
| #endif |
| { |
| __int32_t i0,j0; |
| __uint32_t i,ix; |
| GET_FLOAT_WORD(i0,x); |
| ix = (i0&0x7fffffff); |
| j0 = (ix>>23)-0x7f; |
| if(j0<23) { |
| if(j0<0) { /* raise inexact if x != 0 */ |
| if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */ |
| if(i0>=0) {i0=0;} |
| else if(!FLT_UWORD_IS_ZERO(ix)) |
| { i0=0xbf800000;} |
| } |
| } else { |
| i = (0x007fffff)>>j0; |
| if((i0&i)==0) return x; /* x is integral */ |
| if(huge+x>(float)0.0) { /* raise inexact flag */ |
| if(i0<0) i0 += (0x00800000)>>j0; |
| i0 &= (~i); |
| } |
| } |
| } else { |
| if(!FLT_UWORD_IS_FINITE(ix)) return x+x; /* inf or NaN */ |
| else return x; /* x is integral */ |
| } |
| SET_FLOAT_WORD(x,i0); |
| return x; |
| } |
| |
| #ifdef _DOUBLE_IS_32BITS |
| |
| #ifdef __STDC__ |
| double floor(double x) |
| #else |
| double floor(x) |
| double x; |
| #endif |
| { |
| return (double) floorf((float) x); |
| } |
| |
| #endif /* defined(_DOUBLE_IS_32BITS) */ |
