flow.c (find_auto_inc): Also try to generate a PRE_MODIFY with constant offset.

* flow.c (find_auto_inc): Also try to generate a PRE_MODIFY with
constant offset.

From-SVN: r61333

gcc/ChangeLog

 2003-01-15  Richard Earnshaw  <rearnsha@arm.com>
 
+	* flow.c (find_auto_inc): Also try to generate a PRE_MODIFY with
+	constant offset.
+
+2003-01-15  Richard Earnshaw  <rearnsha@arm.com>
+
 	* arm.h (HAVE_PRE_MODIFY_DISP, HAVE_PRE_MODIFY_REG): Define.
 	(HAVE_POST_MODIFY_DISP, HAVE_POST_MODIFY_REG): Define.
 	(ARM_GO_IF_LEGITIMATE_ADDRESS): Handle pre/post-modify addresses.

gcc/flow.c

@@ -3525,6 +3525,12 @@ find_auto_inc (pbi, x, insn)
 								  addr,
 								  inc_val)),
 			  insn, x, incr, addr);
+      else if (HAVE_PRE_MODIFY_DISP && offset == INTVAL (inc_val))
+	attempt_auto_inc (pbi, gen_rtx_PRE_MODIFY (Pmode, addr,
+						    gen_rtx_PLUS (Pmode,
+								  addr,
+								  inc_val)),
+			  insn, x, incr, addr);
     }
   else if (GET_CODE (inc_val) == REG
 	   && ! reg_set_between_p (inc_val, PREV_INSN (insn),