Initial revision

lib/float/shifter.c

@@ -0,0 +1,75 @@
+/*
+  (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
+  See the copyright notice in the ACK home directory, in the file "Copyright".
+*/
+
+/* $Header$ */
+
+# include "FP_types.h"
+
+void
+b64_sft(e1,n)
+B64	*e1;
+int	n;
+{
+	if (n > 0) {
+		if (n > 63) {
+			e1->l_32 = 0;
+			e1->h_32 = 0;
+			return;
+		}
+		if (n >= 32) {
+			e1->l_32 = e1->h_32;
+			e1->h_32 = 0;
+			n -= 32;
+		}
+		if (n > 0) {
+			e1->l_32 >>= n;
+			if (e1->h_32 != 0) {
+				e1->l_32 |= (e1->h_32 << (32 - n));
+				e1->h_32 >>= n;
+			}
+		}
+		return;
+	}
+	n = -n;
+	if (n > 0) {
+		if (n > 63) {
+			e1->l_32 = 0;
+			e1->h_32 = 0;
+			return;
+		}
+		if (n >= 32) {
+			e1->h_32 = e1->l_32;
+			e1->l_32 = 0;
+			n -= 32;
+		}
+		if (n > 0) {
+			e1->h_32 <<= n;
+			if (e1->l_32 != 0) {
+				e1->h_32 |= (e1->l_32 >> (32 - n));
+				e1->l_32 <<= n;
+			}
+		}
+	}
+}
+
+void
+b64_lsft(e1)
+B64	*e1;
+{
+	/*	shift left 1 bit */
+	e1->h_32 <<= 1;
+	if (e1->l_32 & 0x80000000L) e1->h_32 |= 1;
+	e1->l_32 <<= 1;
+}
+
+void
+b64_rsft(e1)
+B64	*e1;
+{
+	/*	shift right 1 bit */
+	e1->l_32 >>= 1;
+	if (e1->h_32 & 1) e1->l_32 |= 0x80000000L;
+	e1->h_32 >>= 1;
+}