summary refs log tree commit diff
path: root/sysdeps/ieee754/ldbl-96/s_rintl.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/ieee754/ldbl-96/s_rintl.c')
-rw-r--r--sysdeps/ieee754/ldbl-96/s_rintl.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-96/s_rintl.c b/sysdeps/ieee754/ldbl-96/s_rintl.c
new file mode 100644
index 0000000000..9d4777dcc4
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-96/s_rintl.c
@@ -0,0 +1,91 @@
+/* s_rintl.c -- long double version of s_rint.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
+
+/*
+ * 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
+TWO63[2]={
+  9.223372036854775808000000e+18, /* 0x403E, 0x00000000, 0x00000000 */
+ -9.223372036854775808000000e+18  /* 0xC03E, 0x00000000, 0x00000000 */
+};
+
+#ifdef __STDC__
+	long double __rintl(long double x)
+#else
+	long double __rintl(x)
+	long double x;
+#endif
+{
+	int32_t se,j0,sx;
+	u_int32_t i,i0,i1;
+	long double w,t;
+	GET_LDOUBLE_WORDS(se,i0,i1,x);
+	sx = (se>>15)&1;
+	j0 = (se&0x7fff)-0x3fff;
+	if(j0<31) {
+	    if(j0<0) {
+		if(((se&0x7fff)|i0|i1)==0) return x;
+		i1 |= i0;
+		i0 &= 0xe0000000;
+		i0 |= (i1|-i1)&0x80000000;
+		SET_LDOUBLE_MSW(x,i0);
+	        w = TWO63[sx]+x;
+	        t = w-TWO63[sx];
+		GET_LDOUBLE_EXP(i0,t);
+		SET_LDOUBLE_EXP(t,(i0&0x7fff)|(sx<<15));
+	        return t;
+	    } else {
+		i = (0x7fffffff)>>j0;
+		if(((i0&i)|i1)==0) return x; /* x is integral */
+		i>>=1;
+		if(((i0&i)|i1)!=0) {
+		    if(j0==30) i1 = 0x40000000; else
+		    i0 = (i0&(~i))|((0x20000000)>>j0);
+		}
+	    }
+	} else if (j0>62) {
+	    if(j0==0x4000) return x+x;	/* inf or NaN */
+	    else return x;		/* x is integral */
+	} else {
+	    i = ((u_int32_t)(0xffffffff))>>(j0-31);
+	    if((i1&i)==0) return x;	/* x is integral */
+	    i>>=1;
+	    if((i1&i)!=0) i1 = (i1&(~i))|((0x40000000)>>(j0-31));
+	}
+	SET_LDOUBLE_WORDS(x,se,i0,i1);
+	w = TWO63[sx]+x;
+	return w-TWO63[sx];
+}
+weak_alias (__rintl, rintl)