From db66bf68a1cd1d417000032cc255dfe177ce50fc Mon Sep 17 00:00:00 2001
From: Jan Hubicka <hubicka@ucw.cz>
Date: Sun, 12 Apr 2015 07:44:52 +0200
Subject: [PATCH] re PR middle-end/65743 (LTO+FDO build of Firefox crashes at
 startup)

	PR ipa/65743
	* ipa-inline-transform.c (speculation_removed): Remove static var.
	(check_speculations): New function.
	(clone_inlined_nodes): Do not check spculations.
	(inline_call): Call check_speculations.
	* ipa-prop.c (ipa_make_edge_direct_to_target): Do not
	consider non-invariants.

From-SVN: r222017
---
 gcc/ChangeLog              | 10 ++++++++++
 gcc/ipa-inline-transform.c | 20 ++++++++++++++++++--
 gcc/ipa-prop.c             | 26 +++++++++++++++++++++++---
 3 files changed, 51 insertions(+), 5 deletions(-)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 19350f35894..687770055df 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+2015-04-11 Jan Hubicka  <hubicka@ucw.cz>
+
+	PR ipa/65743
+	* ipa-inline-transform.c (speculation_removed): Remove static var.
+	(check_speculations): New function.
+	(clone_inlined_nodes): Do not check spculations.
+	(inline_call): Call check_speculations.
+	* ipa-prop.c (ipa_make_edge_direct_to_target): Do not
+	consider non-invariants.
+
 2015-04-11 Jan Hubicka  <hubicka@ucw.cz>
 	   Martin Liska  <mliska@suse.cz>
 
diff --git a/gcc/ipa-inline-transform.c b/gcc/ipa-inline-transform.c
index 99ed512ea96..5a628f39dd6 100644
--- a/gcc/ipa-inline-transform.c
+++ b/gcc/ipa-inline-transform.c
@@ -64,7 +64,6 @@ along with GCC; see the file COPYING3.  If not see
 
 int ncalls_inlined;
 int nfunctions_inlined;
-bool speculation_removed;
 
 /* Scale frequency of NODE edges by FREQ_SCALE.  */
 
@@ -256,12 +255,29 @@ clone_inlined_nodes (struct cgraph_edge *e, bool duplicate,
       next = e->next_callee;
       if (!e->inline_failed)
         clone_inlined_nodes (e, duplicate, update_original, overall_size, freq_scale);
+    }
+}
+
+/* Check all speculations in N and resolve them if they seems useless. */
+
+static bool
+check_speculations (cgraph_node *n)
+{
+  bool speculation_removed = false;
+  cgraph_edge *next;
+
+  for (cgraph_edge *e = n->callees; e; e = next)
+    {
+      next = e->next_callee;
       if (e->speculative && !speculation_useful_p (e, true))
 	{
 	  e->resolve_speculation (NULL);
 	  speculation_removed = true;
 	}
+      else if (!e->inline_failed)
+	speculation_removed |= check_speculations (e->callee);
     }
+  return speculation_removed;
 }
 
 /* Mark all call graph edges coming out of NODE and all nodes that have been
@@ -310,7 +326,6 @@ inline_call (struct cgraph_edge *e, bool update_original,
   bool predicated = inline_edge_summary (e)->predicate != NULL;
 #endif
 
-  speculation_removed = false;
   /* Don't inline inlined edges.  */
   gcc_assert (e->inline_failed);
   /* Don't even think of inlining inline clone.  */
@@ -360,6 +375,7 @@ inline_call (struct cgraph_edge *e, bool update_original,
     mark_all_inlined_calls_cdtor (e->callee);
   if (opt_for_fn (e->caller->decl, optimize))
     new_edges_found = ipa_propagate_indirect_call_infos (curr, new_edges);
+  check_speculations (e->callee);
   if (update_overall_summary)
    inline_update_overall_summary (to);
   new_size = inline_summaries->get (to)->size;
diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
index 89a4623e0c2..dc8f3606b1e 100644
--- a/gcc/ipa-prop.c
+++ b/gcc/ipa-prop.c
@@ -2626,9 +2626,29 @@ ipa_make_edge_direct_to_target (struct cgraph_edge *ie, tree target,
       target = canonicalize_constructor_val (target, NULL);
       if (!target || TREE_CODE (target) != FUNCTION_DECL)
 	{
-	  if (ie->indirect_info->member_ptr)
-	    /* Member pointer call that goes through a VMT lookup.  */
-	    return NULL;
+	  /* Member pointer call that goes through a VMT lookup.  */
+	  if (ie->indirect_info->member_ptr
+	      /* Or if target is not an invariant expression and we do not
+		 know if it will evaulate to function at runtime.
+		 This can happen when folding through &VAR, where &VAR
+		 is IP invariant, but VAR itself is not.
+
+		 TODO: Revisit this when GCC 5 is branched.  It seems that
+		 member_ptr check is not needed and that we may try to fold
+		 the expression and see if VAR is readonly.  */
+	      || !is_gimple_ip_invariant (target))
+	    {
+	      if (dump_enabled_p ())
+		{
+		  location_t loc = gimple_location_safe (ie->call_stmt);
+		  dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, loc,
+				   "discovered direct call non-invariant "
+				   "%s/%i\n",
+				   ie->caller->name (), ie->caller->order);
+		}
+	      return NULL;
+	    }
+
 
           if (dump_enabled_p ())
 	    {
-- 
2.30.2