needed ldexp routine for exp.c

lang/pc/libpc/exp.c

@@ -11,6 +11,38 @@
 #include <pc_err.h>
 extern	_trp();
 
+static double
+ldexp(fl,exp)
+	double fl;
+	int exp;
+{
+	extern double _fef();
+	int sign = 1;
+	int currexp;
+
+	if (fl<0) {
+		fl = -fl;
+		sign = -1;
+	}
+	fl = _fef(fl,&currexp);
+	exp += currexp;
+	if (exp > 0) {
+		while (exp>30) {
+			fl *= (double) (1L << 30);
+			exp -= 30;
+		}
+		fl *= (double) (1L << exp);
+	}
+	else	{
+		while (exp<-30) {
+			fl /= (double) (1L << 30);
+			exp += 30;
+		}
+		fl /= (double) (1L << -exp);
+	}
+	return sign * fl;
+}
+
 double
 _exp(x)
 	double x;