about summary refs log tree commit diff
path: root/sysdeps/ieee754/ldbl-96/e_remainderl.c
diff options
context:
space:
mode:
authorUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
committerUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
commitabfbdde177c3a7155070dda1b2cdc8292054cc26 (patch)
treee021306b596381fbf8311d2b7eb294e918ff17c8 /sysdeps/ieee754/ldbl-96/e_remainderl.c
parent86421aa57ecfd70963ae66848bd6a6dd3b8e0fe6 (diff)
downloadglibc-abfbdde177c3a7155070dda1b2cdc8292054cc26.tar.gz
glibc-abfbdde177c3a7155070dda1b2cdc8292054cc26.tar.xz
glibc-abfbdde177c3a7155070dda1b2cdc8292054cc26.zip
Update.
Diffstat (limited to 'sysdeps/ieee754/ldbl-96/e_remainderl.c')
-rw-r--r--sysdeps/ieee754/ldbl-96/e_remainderl.c83
1 files changed, 83 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-96/e_remainderl.c b/sysdeps/ieee754/ldbl-96/e_remainderl.c
new file mode 100644
index 0000000000..e721a6e8cd
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-96/e_remainderl.c
@@ -0,0 +1,83 @@
+/* e_remainderl.c -- long double version of e_remainder.c.
+ * Conversion to long double by Ulrich Drepper,
+ * Cygnus Support, drepper@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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: $";
+#endif
+
+/* __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 fmod() return x-[x/p]chopped*p exactlp.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double zero = 0.0;
+#else
+static long double zero = 0.0;
+#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
+{
+	u_int32_t sx,sex,sep,x0,x1,p0,p1;
+	long double p_half;
+
+	GET_LDOUBLE_WORDS(sex,x0,x1,x);
+	GET_LDOUBLE_WORDS(sep,p0,p1,p);
+	sx = sex&0x8000;
+	sep &= 0x7fff;
+	sex &= 0x7fff;
+
+    /* purge off exception values */
+	if((sep|p0|p1)==0) return (x*p)/(x*p); 	/* p = 0 */
+	if((sex==0x7fff)||			/* x not finite */
+	  ((sep==0x7fff)&&			/* p is NaN */
+	   ((p0|p1)!=0)))
+	    return (x*p)/(x*p);
+
+
+	if (sep<0x7ffe) x = __ieee754_fmodl(x,p+p);	/* now x < 2p */
+	if (((sex-sep)|(x0-p0)|(x1-p1))==0) return zero*x;
+	x  = fabsl(x);
+	p  = fabsl(p);
+	if (sep<0x0002) {
+	    if(x+x>p) {
+		x-=p;
+		if(x+x>=p) x -= p;
+	    }
+	} else {
+	    p_half = 0.5*p;
+	    if(x>p_half) {
+		x-=p;
+		if(x>=p_half) x -= p;
+	    }
+	}
+	GET_LDOUBLE_EXP(sex,x);
+	SET_LDOUBLE_EXP(x,sex^sx);
+	return x;
+}