unroll.c (find_splittable_givs): For a DEST_ADDR giv...

        * unroll.c (find_splittable_givs): For a DEST_ADDR giv, do not share
        a register with another DEST_ADDR giv if the address is not valid.

From-SVN: r24673

gcc/ChangeLog

 Thu Jan 14 22:38:41 1999  Jeffrey A Law  (law@cygnus.com)
 
+	* unroll.c (find_splittable_givs): For a DEST_ADDR giv, do not share
+	a register with another DEST_ADDR giv if the address is not valid.
+
 	* pa.c (hppa_expand_epilogue): Save and restore the static chain
 	around the call to mcount.
 

gcc/unroll.c

@@ -2847,8 +2847,11 @@ find_splittable_givs (bl, unroll_type, loop_start, loop_end, increment,
 			  To share a register here, the values must be
 			  equal.  */
 		       && rtx_equal_p (v->same->mult_val, v->mult_val)
-		       && rtx_equal_p (v->same->add_val, v->add_val))
-
+		       && rtx_equal_p (v->same->add_val, v->add_val)
+		       /* If the memory references have different modes,
+			  then the address may not be valid and we must
+			  not share registers.  */
+		       && verify_addresses (v, giv_inc, unroll_number))
 		{
 		  v->dest_reg = v->same->dest_reg;
 		  v->shared = 1;