aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/e_remainderl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/e_remainderl.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c b/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c
new file mode 100644
index 0000000..b7fa68f
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c
@@ -0,0 +1,78 @@
+/* e_fmodl.c -- long double version of e_fmod.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.
+ * ====================================================
+ */
+
+/* __ieee754_remainderl(x,p)
+ * Return :
+ * returns x REM p = x - [x/p]*p as if in infinite
+ * precise arithmetic, where [x/p] is the (infinite bit)
+ * integer nearest x/p (in half way case choose the even one).
+ * Method :
+ * Based on fmodl() return x-[x/p]chopped*p exactlp.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double zero = 0.0L;
+#else
+static long double zero = 0.0L;
+#endif
+
+
+#ifdef __STDC__
+ long double __ieee754_remainderl(long double x, long double p)
+#else
+ long double __ieee754_remainderl(x,p)
+ long double x,p;
+#endif
+{
+ int64_t hx,hp;
+ u_int64_t sx,lx,lp;
+ long double p_half;
+
+ GET_LDOUBLE_WORDS64(hx,lx,x);
+ GET_LDOUBLE_WORDS64(hp,lp,p);
+ sx = hx&0x8000000000000000ULL;
+ hp &= 0x7fffffffffffffffLL;
+ hx &= 0x7fffffffffffffffLL;
+
+ /* purge off exception values */
+ if((hp|(lp&0x7fffffffffffffff))==0) return (x*p)/(x*p); /* p = 0 */
+ if((hx>=0x7ff0000000000000LL)|| /* x not finite */
+ ((hp>=0x7ff0000000000000LL)&& /* p is NaN */
+ (((hp-0x7ff0000000000000LL)|lp)!=0)))
+ return (x*p)/(x*p);
+
+
+ if (hp<=0x7fdfffffffffffffLL) x = __ieee754_fmodl(x,p+p); /* now x < 2p */
+ if (((hx-hp)|(lx-lp))==0) return zero*x;
+ x = fabsl(x);
+ p = fabsl(p);
+ if (hp<0x0020000000000000LL) {
+ if(x+x>p) {
+ x-=p;
+ if(x+x>=p) x -= p;
+ }
+ } else {
+ p_half = 0.5L*p;
+ if(x>p_half) {
+ x-=p;
+ if(x>=p_half) x -= p;
+ }
+ }
+ GET_LDOUBLE_MSW64(hx,x);
+ SET_LDOUBLE_MSW64(x,hx^sx);
+ return x;
+}