diff options
Diffstat (limited to 'libquadmath/math/nextafterq.c')
-rw-r--r-- | libquadmath/math/nextafterq.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/libquadmath/math/nextafterq.c b/libquadmath/math/nextafterq.c new file mode 100644 index 000000000..01bfa6579 --- /dev/null +++ b/libquadmath/math/nextafterq.c @@ -0,0 +1,63 @@ +/* s_nextafterl.c -- long double version of s_nextafter.c. + * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz. + */ + +/* + * ==================================================== + * 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. + * ==================================================== + */ + +#include "quadmath-imp.h" + +__float128 +nextafterq (__float128 x, __float128 y) +{ + int64_t hx,hy,ix,iy; + uint64_t lx,ly; + + GET_FLT128_WORDS64(hx,lx,x); + GET_FLT128_WORDS64(hy,ly,y); + ix = hx&0x7fffffffffffffffLL; /* |x| */ + iy = hy&0x7fffffffffffffffLL; /* |y| */ + + if(((ix>=0x7fff000000000000LL)&&((ix-0x7fff000000000000LL)|lx)!=0) || /* x is nan */ + ((iy>=0x7fff000000000000LL)&&((iy-0x7fff000000000000LL)|ly)!=0)) /* y is nan */ + return x+y; + if(x==y) return y; /* x=y, return y */ + if((ix|lx)==0) { /* x == 0 */ + SET_FLT128_WORDS64(x,hy&0x8000000000000000ULL,1);/* return +-minsubnormal */ + + /* here we should raise an underflow flag */ + return x; + } + if(hx>=0) { /* x > 0 */ + if(hx>hy||((hx==hy)&&(lx>ly))) { /* x > y, x -= ulp */ + if(lx==0) hx--; + lx--; + } else { /* x < y, x += ulp */ + lx++; + if(lx==0) hx++; + } + } else { /* x < 0 */ + if(hy>=0||hx>hy||((hx==hy)&&(lx>ly))){/* x < y, x -= ulp */ + if(lx==0) hx--; + lx--; + } else { /* x > y, x += ulp */ + lx++; + if(lx==0) hx++; + } + } + hy = hx&0x7fff000000000000LL; + if(hy==0x7fff000000000000LL) return x+x;/* overflow */ + if(hy==0) { + /* here we should raise an underflow flag */ + } + SET_FLT128_WORDS64(x,hx,lx); + return x; +} |