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      1  1.1  mrg /* s_floorl.c -- long double version of s_floor.c.
      2  1.1  mrg  * Conversion to IEEE quad long double by Jakub Jelinek, jj (at) ultra.linux.cz.
      3  1.1  mrg  */
      4  1.1  mrg 
      5  1.1  mrg /*
      6  1.1  mrg  * ====================================================
      7  1.1  mrg  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
      8  1.1  mrg  *
      9  1.1  mrg  * Developed at SunPro, a Sun Microsystems, Inc. business.
     10  1.1  mrg  * Permission to use, copy, modify, and distribute this
     11  1.1  mrg  * software is freely granted, provided that this notice
     12  1.1  mrg  * is preserved.
     13  1.1  mrg  * ====================================================
     14  1.1  mrg  */
     15  1.1  mrg 
     16  1.1  mrg #if defined(LIBM_SCCS) && !defined(lint)
     17  1.1  mrg static char rcsid[] = "NetBSD: ";
     18  1.1  mrg #endif
     19  1.1  mrg 
     20  1.1  mrg /*
     21  1.1  mrg  * floorq(x)
     22  1.1  mrg  * Return x rounded toward -inf to integral value
     23  1.1  mrg  * Method:
     24  1.1  mrg  *	Bit twiddling.
     25  1.1  mrg  */
     26  1.1  mrg 
     27  1.1  mrg #define NO_MATH_REDIRECT
     28  1.1  mrg 
     29  1.1  mrg #include "quadmath-imp.h"
     30  1.1  mrg 
     31  1.1  mrg __float128 floorq(__float128 x)
     32  1.1  mrg {
     33  1.1  mrg 	int64_t i0,i1,j0;
     34  1.1  mrg 	uint64_t i,j;
     35  1.1  mrg 	GET_FLT128_WORDS64(i0,i1,x);
     36  1.1  mrg 	j0 = ((i0>>48)&0x7fff)-0x3fff;
     37  1.1  mrg 	if(j0<48) {
     38  1.1  mrg 	    if(j0<0) {
     39  1.1  mrg 		/* return 0*sign(x) if |x|<1 */
     40  1.1  mrg 		if(i0>=0) {i0=i1=0;}
     41  1.1  mrg 		else if(((i0&0x7fffffffffffffffLL)|i1)!=0)
     42  1.1  mrg 		    { i0=0xbfff000000000000ULL;i1=0;}
     43  1.1  mrg 	    } else {
     44  1.1  mrg 		i = (0x0000ffffffffffffULL)>>j0;
     45  1.1  mrg 		if(((i0&i)|i1)==0) return x; /* x is integral */
     46  1.1  mrg 		if(i0<0) i0 += (0x0001000000000000LL)>>j0;
     47  1.1  mrg 		i0 &= (~i); i1=0;
     48  1.1  mrg 	    }
     49  1.1  mrg 	} else if (j0>111) {
     50  1.1  mrg 	    if(j0==0x4000) return x+x;	/* inf or NaN */
     51  1.1  mrg 	    else return x;		/* x is integral */
     52  1.1  mrg 	} else {
     53  1.1  mrg 	    i = -1ULL>>(j0-48);
     54  1.1  mrg 	    if((i1&i)==0) return x;	/* x is integral */
     55  1.1  mrg 	    if(i0<0) {
     56  1.1  mrg 		if(j0==48) i0+=1;
     57  1.1  mrg 		else {
     58  1.1  mrg 		    j = i1+(1LL<<(112-j0));
     59  1.1  mrg 		    if(j<i1) i0 +=1 ; 	/* got a carry */
     60  1.1  mrg 		    i1=j;
     61  1.1  mrg 		}
     62  1.1  mrg 	    }
     63  1.1  mrg 	    i1 &= (~i);
     64  1.1  mrg 	}
     65  1.1  mrg 	SET_FLT128_WORDS64(x,i0,i1);
     66  1.1  mrg 	return x;
     67  1.1  mrg }
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