Audit cgraphunit for optimization attributes

[Jan Hubicka]

Hi,
this patch updates cgraphunit.  One non-trivial case is expand_thunk.  Jason, I
think expand_thunk should always inherit optimization/target attributes from
the function it is associated with, right?

Bootstrapped/regtested x86_64-linux.

Honza

        * cgraphunit.c (analyze_functions): Use opt_for_fn.

Index: cgraphunit.c
===================================================================
--- cgraphunit.c        (revision 217633)
+++ cgraphunit.c        (working copy)
@@ -1001,7 +1001,7 @@ analyze_functions (void)
              for (edge = cnode->callees; edge; edge = edge->next_callee)
                if (edge->callee->definition)
                   enqueue_node (edge->callee);
-             if (optimize && flag_devirtualize)
+             if (optimize && opt_for_fn (cnode->decl, flag_devirtualize))
                {
                  cgraph_edge *next;