Fix handling of CIF_FINAL_ERROR codes in inliner

[Jan Hubicka <hubicka at ucw dot cz>]

Hi,
this patch fixes accounting error in inliner growth calculation.  We have
CIF_FINAL_NORMAL and CIF_FINAL_ERROR inline_failed codes.  The FINAL_ERROR
means that it can not be revisited and inlining will fail.
Problem is that CIF_FINAL_ERROR is set at link time and not revisited
during LTO merging that may turn CIF_FINAL_ERROR into CIF_FINAL_NORMAL.

This patch makes the revisit to happen and also makes can_inline_edge_p
to more consistently short circuit when inlining is known to be impossible.
I also went across cif-code.def and fixed codes.

Bootstrapped/regtested x86_64-linux. This patch fixes regression on vortex
benchmark (among others probably). I will commit it after bit of more
testing.

Honza

	* ipa-inline.c (can_inline_edge_p): Short circuit if inline_failed
	already is final.
	(ipa_inline): Recompute inline_failed codes.
	* cif-code.def (FUNCTION_NOT_OPTIMIZED, REDEFINED_EXTERN_INLINE,
	USES_COMDAT_LOCAL, ATTRIBUTE_MISMATCH, UNREACHABLE): Declare as 
	CIF_FINAL_ERROR.
Index: ipa-inline.c
===================================================================
--- ipa-inline.c	(revision 221523)
+++ ipa-inline.c	(working copy)
@@ -312,6 +312,15 @@ static bool
 can_inline_edge_p (struct cgraph_edge *e, bool report,
 		   bool disregard_limits = false, bool early = false)
 {
+  gcc_checking_assert (e->inline_failed);
+
+  if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
+    {
+      if (report)
+        report_inline_failed_reason (e);
+      return false;
+    }
+
   bool inlinable = true;
   enum availability avail;
   cgraph_node *callee = e->callee->ultimate_alias_target (&avail);
@@ -323,9 +332,7 @@ can_inline_edge_p (struct cgraph_edge *e
   struct function *caller_fun = caller->get_fun ();
   struct function *callee_fun = callee ? callee->get_fun () : NULL;
 
-  gcc_assert (e->inline_failed);
-
-  if (!callee || !callee->definition)
+  if (!callee->definition)
     {
       e->inline_failed = CIF_BODY_NOT_AVAILABLE;
       inlinable = false;
@@ -363,8 +370,7 @@ can_inline_edge_p (struct cgraph_edge *e
     }
   /* TM pure functions should not be inlined into non-TM_pure
      functions.  */
-  else if (is_tm_pure (callee->decl)
-	   && !is_tm_pure (caller->decl))
+  else if (is_tm_pure (callee->decl) && !is_tm_pure (caller->decl))
     {
       e->inline_failed = CIF_UNSPECIFIED;
       inlinable = false;
@@ -2289,7 +2295,22 @@ ipa_inline (void)
   nnodes = ipa_reverse_postorder (order);
 
   FOR_EACH_FUNCTION (node)
-    node->aux = 0;
+    {
+      node->aux = 0;
+
+      /* Recompute the default reasons for inlining because they may have
+	 changed during merging.  */
+      if (in_lto_p)
+	{
+	  for (cgraph_edge *e = node->callees; e; e = e->next_callee)
+	    {
+	      gcc_assert (e->inline_failed);
+	      initialize_inline_failed (e);
+	    }
+	  for (cgraph_edge *e = node->indirect_calls; e; e = e->next_callee)
+	    initialize_inline_failed (e);
+	}
+    }
 
   if (dump_file)
     fprintf (dump_file, "\nFlattening functions:\n");
Index: cif-code.def
===================================================================
--- cif-code.def	(revision 221523)
+++ cif-code.def	(working copy)
@@ -39,7 +39,7 @@ DEFCIFCODE(FUNCTION_NOT_CONSIDERED, CIF_
 	   N_("function not considered for inlining"))
 
 /* Caller is compiled with optimizations disabled.  */
-DEFCIFCODE(FUNCTION_NOT_OPTIMIZED, CIF_FINAL_NORMAL,
+DEFCIFCODE(FUNCTION_NOT_OPTIMIZED, CIF_FINAL_ERROR,
 	   N_("caller is not optimized"))
 
 /* Inlining failed owing to unavailable function body.  */
@@ -47,7 +47,7 @@ DEFCIFCODE(BODY_NOT_AVAILABLE, CIF_FINAL
 	   N_("function body not available"))
 
 /* Extern inline function that has been redefined.  */
-DEFCIFCODE(REDEFINED_EXTERN_INLINE, CIF_FINAL_NORMAL,
+DEFCIFCODE(REDEFINED_EXTERN_INLINE, CIF_FINAL_ERROR,
 	   N_("redefined extern inline functions are not considered for "
 	      "inlining"))
 
@@ -121,13 +121,13 @@ DEFCIFCODE(OPTIMIZATION_MISMATCH, CIF_FI
 	   N_("optimization level attribute mismatch"))
 
 /* We can't inline because the callee refers to comdat-local symbols.  */
-DEFCIFCODE(USES_COMDAT_LOCAL, CIF_FINAL_NORMAL,
+DEFCIFCODE(USES_COMDAT_LOCAL, CIF_FINAL_ERROR,
 	   N_("callee refers to comdat-local symbols"))
 
 /* We can't inline because of mismatched caller/callee attributes.  */
-DEFCIFCODE(ATTRIBUTE_MISMATCH, CIF_FINAL_NORMAL,
+DEFCIFCODE(ATTRIBUTE_MISMATCH, CIF_FINAL_ERROR,
 	   N_("function attribute mismatch"))
 
 /* We proved that the call is unreachable.  */
-DEFCIFCODE(UNREACHABLE, CIF_FINAL_NORMAL,
+DEFCIFCODE(UNREACHABLE, CIF_FINAL_ERROR,
 	   N_("unreachable"))