[AArch64 costs 18/18] Dump a message if we are unable to cost an insn.

gcc/

	* config/aarch64/aarch64.c (aarch64_rtx_costs): Handle the case
	where we were unable to cost an RTX.

From-SVN: r210510

gcc/ChangeLog

 2014-05-16  James Greenhalgh  <james.greenhalgh@arm.com>
 
+	* config/aarch64/aarch64.c (aarch64_rtx_costs): Handle the case
+	where we were unable to cost an RTX.
+
+2014-05-16  James Greenhalgh  <james.greenhalgh@arm.com>
+
 	* config/aarch64/aarch64.c (aarch64_rtx_costs): Cost SYMBOL_REF,
 	HIGH, LO_SUM.
 

gcc/config/aarch64/aarch64.c

@@ -5787,7 +5787,11 @@ cost_plus:
 
       /* Fall through.  */
     default:
-      break;
+      if (dump_file && (dump_flags & TDF_DETAILS))
+	fprintf (dump_file,
+		 "\nFailed to cost RTX.  Assuming default cost.\n");
+
+      return true;
     }
   return false;
 }