about summary refs log tree commit diff
path: root/sysdeps/ieee754/ldbl-128/s_rintl.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/ieee754/ldbl-128/s_rintl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128/s_rintl.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_rintl.c b/sysdeps/ieee754/ldbl-128/s_rintl.c
new file mode 100644
index 0000000000..c3fc3ba193
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/s_rintl.c
@@ -0,0 +1,90 @@
+/* s_rintl.c -- long double version of s_rint.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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: $";
+#endif
+
+/*
+ * rintl(x)
+ * Return x rounded to integral value according to the prevailing
+ * rounding mode.
+ * Method:
+ *	Using floating addition.
+ * Exception:
+ *	Inexact flag raised if x not equal to rintl(x).
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double
+#else
+static long double
+#endif
+TWO112[2]={
+  5.19229685853482762853049632922009600E+33L, /* 0x406F000000000000, 0 */
+ -5.19229685853482762853049632922009600E+33L  /* 0xC06F000000000000, 0 */
+};
+
+#ifdef __STDC__
+	long double __rintl(long double x)
+#else
+	long double __rintl(x)
+	long double x;
+#endif
+{
+	int64_t i0,j0,sx;
+	u_int64_t i,i1;
+	long double w,t;
+	GET_LDOUBLE_WORDS64(i0,i1,x);
+	sx = (((u_int64_t)i0)>>63);
+	j0 = ((i0>>48)&0x7fff)-0x3fff;
+	if(j0<48) {
+	    if(j0<0) {
+		if(((i0&0x7fffffffffffffffLL)|i1)==0) return x;
+		i1 |= (i0&0x0000ffffffffffffLL);
+		i0 &= 0xffffe00000000000ULL;
+		i0 |= ((i1|-i1)>>16)&0x0000800000000000LL;
+		SET_LDOUBLE_MSW64(x,i0);
+	        w = TWO112[sx]+x;
+	        t = w-TWO112[sx];
+		GET_LDOUBLE_MSW64(i0,t);
+		SET_LDOUBLE_MSW64(t,(i0&0x7fffffffffffffffLL)|(sx<<63));
+	        return t;
+	    } else {
+		i = (0x0000ffffffffffffLL)>>j0;
+		if(((i0&i)|i1)==0) return x; /* x is integral */
+		i>>=1;
+		if(((i0&i)|i1)!=0) {
+		    if(j0==47) i1 = 0x4000000000000000ULL; else
+		    i0 = (i0&(~i))|((0x0000200000000000LL)>>j0);
+		}
+	    }
+	} else if (j0>111) {
+	    if(j0==0x4000) return x+x;	/* inf or NaN */
+	    else return x;		/* x is integral */
+	} else {
+	    i = -1ULL>>(j0-48);
+	    if((i1&i)==0) return x;	/* x is integral */
+	    i>>=1;
+	    if((i1&i)!=0) i1 = (i1&(~i))|((0x4000000000000000LL)>>(j0-48));
+	}
+	SET_LDOUBLE_WORDS64(x,i0,i1);
+	w = TWO112[sx]+x;
+	return w-TWO112[sx];
+}
+weak_alias (__rintl, rintl)