Initial revision

mach/proto/fp/cfu.c

@@ -0,0 +1,43 @@
+/*
+		CONVERT FLOAT TO UNSIGNED
+
+		N.B. The caller must know what it is getting.
+		     A LONG is always returned. If it is an
+		     integer the high byte is cleared first.
+*/
+
+#include "FP_trap.h"
+#include "FP_types.h"
+
+long
+cfu(ds,ss,src)
+int	ds;	/* destination size (2 or 4) */
+int	ss;	/* source size	    (4 or 8) */
+_double	src;	/* assume worst case */
+{
+	EXTEND	buf;
+	long	new;
+	short	newint, max_exp;
+
+	extend(&src,&buf,ss);	/* get extended format	*/
+#ifdef	PRT_EXT
+	prt_ext("CFU() entry:",&buf);
+#endif	PRT_EXT
+	buf.exp--;		/* additional bias correction */
+	if (buf.exp < 1) {	/* no conversion needed	*/
+		src.__double[ss == 8] = 0L;
+		return(0L);
+	}
+	max_exp = (ds << 3);
+	if (buf.exp > max_exp) {
+#ifdef	PRT_EXT
+		prt_ext("CFU() INT OVERFLOW",&buf);
+#endif	PRT_EXT
+		trap(EIOVFL);	/* integer overflow	*/
+		buf.exp %= max_exp;
+	}
+	new = buf.m1 >> (32-buf.exp);
+done:
+	src.__double[ss == 8] = new;
+	return(new);
+}