[PATCH] avail_expr_stack is no longer file scoped

       PR tree-optimization/47679
        * tree-ssa-dom.c (avail_exprs_stack): No longer file scoped.  Move
        it here ...
        (dom_opt_dom_walker): New private member holding the avail_exprs_stack
        object.  Update constructor.
        (pass_dominator::execute):  Corresponding chagnes to declaration
        and initialization of avail_exprs_stack.  Update constructor call
        for dom_opt_dom_walker object.
        (lookup_avail_expr, record_cond): Accept additional argument.  Pass
        it down to children as needed.
        (record_equivalences_from_incoming_edge): Likewise.
        (eliminate_redundant_computations): Likewise.
        (record_equivalences_from_stmt): Likewise.
        (simplify_stmt_for_jump_threading): Likewise.
        (record_temporary_equivalences): Likewise.
        (optimize_stmt): Likewise.
        (dom_opt_dom_walker::thread_across_edge): Update access to
        avail_exprs_stack object and pass it to children as needed.
        (dom_opt_dom_walker::before_dom_children): Similarly.
        (dom_opt_dom_walker::after_dom_children): Similarly.
        * tree-ssa-threadedge.c (pfn_simplify): New typedef.
        (record_temporary_equivalences_from_stmts_at_dest): Use new typedef.
        Add avail_expr_stack argument.  Pass it to children as needed.
        (dummy_simplify): Likewise.
        (simplify_control_stmt_condition): Likewise.
        (thread_around_empty_blocks): Likewise.
        (thread_through_normal_block): Likewise.
        (thread_across_edge): Likewise.
        * tree-ssa-threadedge.h (thread_across_edge): Update prototype.
        * tree-vrp.c (simplify_stmt_for_jump_threading): Update.

From-SVN: r227931

gcc/ChangeLog

 2015-09-18  Jeff Law  <law@redhat.com>
 
 	PR tree-optimization/47679
+	* tree-ssa-dom.c (avail_exprs_stack): No longer file scoped.  Move
+	it here ...
+	(dom_opt_dom_walker): New private member holding the avail_exprs_stack
+	object.  Update constructor.
+	(pass_dominator::execute):  Corresponding chagnes to declaration
+	and initialization of avail_exprs_stack.  Update constructor call
+	for dom_opt_dom_walker object.
+	(lookup_avail_expr, record_cond): Accept additional argument.  Pass
+	it down to children as needed.
+	(record_equivalences_from_incoming_edge): Likewise.
+	(eliminate_redundant_computations): Likewise.
+	(record_equivalences_from_stmt): Likewise.
+	(simplify_stmt_for_jump_threading): Likewise.
+	(record_temporary_equivalences): Likewise.
+	(optimize_stmt): Likewise.
+	(dom_opt_dom_walker::thread_across_edge): Update access to
+	avail_exprs_stack object and pass it to children as needed.
+	(dom_opt_dom_walker::before_dom_children): Similarly.
+	(dom_opt_dom_walker::after_dom_children): Similarly.
+	* tree-ssa-threadedge.c (pfn_simplify): New typedef.
+	(record_temporary_equivalences_from_stmts_at_dest): Use new typedef.
+	Add avail_expr_stack argument.  Pass it to children as needed.
+	(dummy_simplify): Likewise.
+	(simplify_control_stmt_condition): Likewise.
+	(thread_around_empty_blocks): Likewise.
+	(thread_through_normal_block): Likewise.
+	(thread_across_edge): Likewise.
+	* tree-ssa-threadedge.h (thread_across_edge): Update prototype.
+	* tree-vrp.c (simplify_stmt_for_jump_threading): Update.
+
+	PR tree-optimization/47679
 	* tree-ssa-dom.c (const_and_copies): No longer file scoped.  Move
 	it here ...
 	(dom_opt_dom_walker): New private member holding the const_and_copies

gcc/tree-ssa-threadedge.c

@@ -56,6 +56,8 @@ static int stmt_count;
 /* Array to record value-handles per SSA_NAME.  */
 vec<tree> ssa_name_values;
 
+typedef tree (pfn_simplify) (gimple, gimple, class avail_exprs_stack *);
+
 /* Set the value for the SSA name NAME to VALUE.  */
 
 void
@@ -256,10 +258,10 @@ fold_assignment_stmt (gimple stmt)
 
 static gimple
 record_temporary_equivalences_from_stmts_at_dest (edge e,
-						  const_and_copies *const_and_copies,
-						  tree (*simplify) (gimple,
-								    gimple),
-						  bool backedge_seen)
+    const_and_copies *const_and_copies,
+    avail_exprs_stack *avail_exprs_stack,
+    pfn_simplify simplify,
+    bool backedge_seen)
 {
   gimple stmt = NULL;
   gimple_stmt_iterator gsi;
@@ -412,7 +414,7 @@ record_temporary_equivalences_from_stmts_at_dest (edge e,
           if (!cached_lhs
               || (TREE_CODE (cached_lhs) != SSA_NAME
                   && !is_gimple_min_invariant (cached_lhs)))
-            cached_lhs = (*simplify) (stmt, stmt);
+            cached_lhs = (*simplify) (stmt, stmt, avail_exprs_stack);
 
 	  /* Restore the statement's original uses/defs.  */
 	  i = 0;
@@ -445,7 +447,8 @@ record_temporary_equivalences_from_stmts_at_dest (edge e,
    necessarily valid.  We use this callback rather than the ones provided by
    DOM/VRP to achieve that effect.  */
 static tree
-dummy_simplify (gimple stmt1 ATTRIBUTE_UNUSED, gimple stmt2 ATTRIBUTE_UNUSED)
+dummy_simplify (gimple stmt1 ATTRIBUTE_UNUSED, gimple stmt2 ATTRIBUTE_UNUSED,
+		class avail_exprs_stack *avail_exprs_stack ATTRIBUTE_UNUSED)
 {
   return NULL_TREE;
 }
@@ -459,13 +462,16 @@ dummy_simplify (gimple stmt1 ATTRIBUTE_UNUSED, gimple stmt2 ATTRIBUTE_UNUSED)
    a condition using pass specific information.
 
    Return the simplified condition or NULL if simplification could
-   not be performed.  */
+   not be performed. 
+
+   The available expression table is referenced via AVAIL_EXPRS_STACK.  */
 
 static tree
 simplify_control_stmt_condition (edge e,
 				 gimple stmt,
+				 class avail_exprs_stack *avail_exprs_stack,
 				 gcond *dummy_cond,
-				 tree (*simplify) (gimple, gimple),
+				 pfn_simplify simplify,
 				 bool handle_dominating_asserts)
 {
   tree cond, cached_lhs;
@@ -552,7 +558,7 @@ simplify_control_stmt_condition (edge e,
 	 then use the pass specific callback to simplify the condition.  */
       if (!cached_lhs
           || !is_gimple_min_invariant (cached_lhs))
-        cached_lhs = (*simplify) (dummy_cond, stmt);
+        cached_lhs = (*simplify) (dummy_cond, stmt, avail_exprs_stack);
 
       /* If we were just testing that an integral type was != 0, and that
 	 failed, just return the first operand.  This gives the FSM code a
@@ -614,7 +620,7 @@ simplify_control_stmt_condition (edge e,
       /* If we haven't simplified to an invariant yet, then use the
 	 pass specific callback to try and simplify it further.  */
       if (cached_lhs && ! is_gimple_min_invariant (cached_lhs))
-        cached_lhs = (*simplify) (stmt, stmt);
+        cached_lhs = (*simplify) (stmt, stmt, avail_exprs_stack);
 
       /* We couldn't find an invariant.  But, callers of this
 	 function may be able to do something useful with the
@@ -764,12 +770,16 @@ propagate_threaded_block_debug_into (basic_block dest, basic_block src)
    return false.
 
    DUMMY_COND, HANDLE_DOMINATING_ASSERTS and SIMPLIFY are used to
-   try and simplify the condition at the end of TAKEN_EDGE->dest.  */
+   try and simplify the condition at the end of TAKEN_EDGE->dest. 
+
+   The available expression table is referenced via AVAIL_EXPRS_STACK.  */
+
 static bool
 thread_around_empty_blocks (edge taken_edge,
 			    gcond *dummy_cond,
+			    class avail_exprs_stack *avail_exprs_stack,
 			    bool handle_dominating_asserts,
-			    tree (*simplify) (gimple, gimple),
+			    pfn_simplify simplify,
 			    bitmap visited,
 			    vec<jump_thread_edge *> *path,
 			    bool *backedge_seen_p)
@@ -818,6 +828,7 @@ thread_around_empty_blocks (edge taken_edge,
 		simplify = dummy_simplify;
 	      return thread_around_empty_blocks (taken_edge,
 						 dummy_cond,
+						 avail_exprs_stack,
 						 handle_dominating_asserts,
 						 simplify,
 						 visited,
@@ -846,7 +857,8 @@ thread_around_empty_blocks (edge taken_edge,
     simplify = dummy_simplify;
 
   /* Extract and simplify the condition.  */
-  cond = simplify_control_stmt_condition (taken_edge, stmt, dummy_cond,
+  cond = simplify_control_stmt_condition (taken_edge, stmt,
+					  avail_exprs_stack, dummy_cond,
 					  simplify, handle_dominating_asserts);
 
   /* If the condition can be statically computed and we have not already
@@ -869,6 +881,7 @@ thread_around_empty_blocks (edge taken_edge,
 
       thread_around_empty_blocks (taken_edge,
 				  dummy_cond,
+				  avail_exprs_stack,
 				  handle_dominating_asserts,
 				  simplify,
 				  visited,
@@ -1187,7 +1200,8 @@ thread_through_normal_block (edge e,
 			     gcond *dummy_cond,
 			     bool handle_dominating_asserts,
 			     const_and_copies *const_and_copies,
-			     tree (*simplify) (gimple, gimple),
+			     avail_exprs_stack *avail_exprs_stack,
+			     pfn_simplify simplify,
 			     vec<jump_thread_edge *> *path,
 			     bitmap visited,
 			     bool *backedge_seen_p)
@@ -1210,6 +1224,7 @@ thread_through_normal_block (edge e,
      temporary equivalences we can detect.  */
   gimple stmt
     = record_temporary_equivalences_from_stmts_at_dest (e, const_and_copies,
+							avail_exprs_stack,
 							simplify,
 							*backedge_seen_p);
 
@@ -1248,7 +1263,8 @@ thread_through_normal_block (edge e,
       tree cond;
 
       /* Extract and simplify the condition.  */
-      cond = simplify_control_stmt_condition (e, stmt, dummy_cond, simplify,
+      cond = simplify_control_stmt_condition (e, stmt, avail_exprs_stack,
+					      dummy_cond, simplify,
 					      handle_dominating_asserts);
 
       if (!cond)
@@ -1293,6 +1309,7 @@ thread_through_normal_block (edge e,
 	  bitmap_set_bit (visited, e->dest->index);
 	  thread_around_empty_blocks (taken_edge,
 				      dummy_cond,
+				      avail_exprs_stack,
 				      handle_dominating_asserts,
 				      simplify,
 				      visited,
@@ -1348,8 +1365,10 @@ thread_through_normal_block (edge e,
    the simplified condition with left-hand sides of ASSERT_EXPRs they are
    used in.
 
-   STACK is used to undo temporary equivalences created during the walk of
-   E->dest.
+   CONST_AND_COPIES is used to undo temporary equivalences created during the
+   walk of E->dest.
+
+   The available expression table is referenced vai AVAIL_EXPRS_STACK.
 
    SIMPLIFY is a pass-specific function used to simplify statements.  */
 
@@ -1357,9 +1376,10 @@ void
 thread_across_edge (gcond *dummy_cond,
 		    edge e,
 		    bool handle_dominating_asserts,
-		    const_and_copies *const_and_copies,
-		    avail_exprs_stack *avail_exprs_stack,
-		    tree (*simplify) (gimple, gimple))
+		    class const_and_copies *const_and_copies,
+		    class avail_exprs_stack *avail_exprs_stack,
+		    tree (*simplify) (gimple, gimple,
+				      class avail_exprs_stack *))
 {
   bitmap visited = BITMAP_ALLOC (NULL);
   bool backedge_seen;
@@ -1376,7 +1396,9 @@ thread_across_edge (gcond *dummy_cond,
 
   int threaded = thread_through_normal_block (e, dummy_cond,
 					      handle_dominating_asserts,
-					      const_and_copies, simplify, path,
+					      const_and_copies,
+					      avail_exprs_stack,
+					      simplify, path,
 					      visited, &backedge_seen);
   if (threaded > 0)
     {
@@ -1467,6 +1489,7 @@ thread_across_edge (gcond *dummy_cond,
 	  simplify = dummy_simplify;
 	found = thread_around_empty_blocks (taken_edge,
 					    dummy_cond,
+					    avail_exprs_stack,
 					    handle_dominating_asserts,
 					    simplify,
 					    visited,
@@ -1479,7 +1502,9 @@ thread_across_edge (gcond *dummy_cond,
 	if (!found)
 	  found = thread_through_normal_block (path->last ()->e, dummy_cond,
 					       handle_dominating_asserts,
-					       const_and_copies, simplify, path,
+					       const_and_copies,
+					       avail_exprs_stack,
+					       simplify, path,
 					       visited, &backedge_seen) > 0;
 
 	/* If we were able to thread through a successor of E->dest, then

gcc/tree-ssa-threadedge.h

@@ -33,6 +33,6 @@ extern void propagate_threaded_block_debug_into (basic_block, basic_block);
 extern void thread_across_edge (gcond *, edge, bool,
 				const_and_copies *,
 				avail_exprs_stack *,
-				tree (*) (gimple, gimple));
+				tree (*) (gimple, gimple, avail_exprs_stack *));
 
 #endif /* GCC_TREE_SSA_THREADEDGE_H */

gcc/tree-vrp.c

@@ -10066,7 +10066,8 @@ const_and_copies *equiv_stack;
    for any overflow warnings.  */
 
 static tree
-simplify_stmt_for_jump_threading (gimple stmt, gimple within_stmt)
+simplify_stmt_for_jump_threading (gimple stmt, gimple within_stmt,
+    class avail_exprs_stack *avail_exprs_stack ATTRIBUTE_UNUSED)
 {
   if (gcond *cond_stmt = dyn_cast <gcond *> (stmt))
     return vrp_evaluate_conditional (gimple_cond_code (cond_stmt),