Initial revision

lib/float/cif4.c

@@ -0,0 +1,56 @@
+/*
+  (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
+  See the copyright notice in the ACK home directory, in the file "Copyright".
+*/
+
+/* $Header$ */
+
+/*
+	CONVERT INTEGER TO SINGLE (CIF n 4)
+
+	THIS ROUTINE WORKS BY FILLING AN EXTENDED
+	WITH THE INTEGER VALUE IN EXTENDED FORMAT
+	AND USES COMPACT() TO PUT IT INTO THE PROPER
+	FLOATING POINT PRECISION.
+*/
+
+#include "FP_types.h"
+
+void
+cif4(ss,src)
+int	ss;	/* source size */
+long	src;	/* largest possible integer to convert */
+{
+	EXTEND	buf;
+	short	*ipt;
+	long	i_src;
+	SINGLE	*result;
+
+	zrf_ext(&buf);
+	if (ss == sizeof(long))	{
+		buf.exp = 31;
+		i_src = src;
+		result = (SINGLE *) &src;
+	}
+	else	{
+		ipt = (short *) &src;
+		i_src = (long) *ipt;
+		buf.exp = 15;
+		result = (SINGLE *) &ss;
+	}
+	if (i_src == 0)	{
+		*result = (SINGLE) 0L;
+		return;
+	}
+			/* ESTABLISHED THAT src != 0	*/
+			/* adjust exponent field	*/
+	buf.sign = (i_src < 0) ? 0x8000 : 0;
+			/* clear sign bit of integer	*/
+			/* move to mantissa field	*/
+	buf.m1 = (i_src < 0) ? -i_src : i_src;
+			/* adjust mantissa field	*/
+	if (ss != sizeof(long))
+		buf.m1 <<= 16;
+	nrm_ext(&buf);		/* adjust mantissa field	*/
+	compact(&buf, result,sizeof(SINGLE));	/* put on stack */
+}