Initial revision

mach/proto/fp/sub_ext.c

@@ -0,0 +1,28 @@
+/*
+#define	PRT_EXT
+	SUBTRACT EXTENDED FORMAT
+*/
+	/*	assumes that e1 >= e2 on entry	*/
+	/*	no test is made to check this	*/
+	/*	so make sure yourself		*/
+
+#include "FP_types.h"
+sub_ext(e1,e2)
+EXTEND	*e1,*e2;
+{
+#ifdef	PRT_EXT
+	prt_ext("before SUB_EXT() e1:",e1);
+	prt_ext("before SUB_EXT() e2:",e2);
+#endif	PRT_EXT
+	if (e2->m2 > e1->m2)
+		e1->m1 -= 1;	/* carry in */
+	e1->m1 -= e2->m1;
+	e1->m2 -= e2->m2;
+#ifdef	PRT_EXT
+	prt_ext("after  SUB_EXT() e1:",e1);
+#endif	PRT_EXT
+	nrm_ext(e1);
+#ifdef	PRT_EXT
+	prt_ext("after  NRM_EXT() e1:",e1);
+#endif	PRT_EXT
+}