From ee2ee92d62c43f6658d37ddea4c316d2089d0fe9 Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Tue, 3 Sep 2013 04:09:12 +0000 Subject: math: rewrite remainder functions (remainder, remquo, fmod, modf) * results are exact * modfl follows truncl (raises inexact flag spuriously now) * modf and modff only had cosmetic cleanup * remainder is just a wrapper around remquo now * using iterative shift+subtract for remquo and fmod * ld80 and ld128 are supported as well --- src/math/remainderf.c | 60 ++++----------------------------------------------- 1 file changed, 4 insertions(+), 56 deletions(-) (limited to 'src/math/remainderf.c') diff --git a/src/math/remainderf.c b/src/math/remainderf.c index 77671039..b418bbff 100644 --- a/src/math/remainderf.c +++ b/src/math/remainderf.c @@ -1,59 +1,7 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/e_remainderf.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. - * ==================================================== - */ +#include -#include "libm.h" - -float remainderf(float x, float p) +float remainderf(float x, float y) { - int32_t hx,hp; - uint32_t sx; - float p_half; - - GET_FLOAT_WORD(hx, x); - GET_FLOAT_WORD(hp, p); - sx = hx & 0x80000000; - hp &= 0x7fffffff; - hx &= 0x7fffffff; - - /* purge off exception values */ - if (hp == 0 || hx >= 0x7f800000 || hp > 0x7f800000) /* p = 0, x not finite, p is NaN */ - return (x*p)/(x*p); - - if (hp <= 0x7effffff) - x = fmodf(x, p + p); /* now x < 2p */ - if (hx - hp == 0) - return 0.0f*x; - x = fabsf(x); - p = fabsf(p); - if (hp < 0x01000000) { - if (x + x > p) { - x -= p; - if (x + x >= p) - x -= p; - } - } else { - p_half = 0.5f*p; - if (x > p_half) { - x -= p; - if (x >= p_half) - x -= p; - } - } - GET_FLOAT_WORD(hx, x); - if ((hx & 0x7fffffff) == 0) - hx = 0; - SET_FLOAT_WORD(x, hx ^ sx); - return x; + int q; + return remquof(x, y, &q); } -- cgit v1.2.1