[AArch64][14/14] Reuse target_option_current_node when passing pragma string to target attribute

	* config/aarch64/aarch64.c (aarch64_option_valid_attribute_p):
	Exit early and use target_option_current_node if processing current
	pragma.

From-SVN: r226567

gcc/ChangeLog

 2015-08-04  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
+	* config/aarch64/aarch64.c (aarch64_option_valid_attribute_p):
+	Exit early and use target_option_current_node if processing current
+	pragma.
+
+2015-08-04  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
 	* doc/extend.texi (AArch64 Function Attributes): New node.
 	(AArch64 Pragmas): Likewise.
 

gcc/config/aarch64/aarch64.c

@@ -8414,6 +8414,18 @@ aarch64_option_valid_attribute_p (tree fndecl, tree, tree args, int)
   tree old_optimize;
   tree new_target, new_optimize;
   tree existing_target = DECL_FUNCTION_SPECIFIC_TARGET (fndecl);
+
+  /* If what we're processing is the current pragma string then the
+     target option node is already stored in target_option_current_node
+     by aarch64_pragma_target_parse in aarch64-c.c.  Use that to avoid
+     having to re-parse the string.  This is especially useful to keep
+     arm_neon.h compile times down since that header contains a lot
+     of intrinsics enclosed in pragmas.  */
+  if (!existing_target && args == current_target_pragma)
+    {
+      DECL_FUNCTION_SPECIFIC_TARGET (fndecl) = target_option_current_node;
+      return true;
+    }
   tree func_optimize = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl);
 
   old_optimize = build_optimization_node (&global_options);