Used visited flag to check for loops in find_conds

[r5087]

diff --git a/ir/opt/ifconv.c b/ir/opt/ifconv.c
index 49be52a..8755820 100644 (file)
--- a/ir/opt/ifconv.c
+++ b/ir/opt/ifconv.c
@@ -373,7 +373,7 @@ static int cond_cmp(const void *a, const void *b, size_t size)
 /**
  * @see find_conds.
  */
-static void _find_conds(ir_node *irn, ir_node *start_block,
+static void _find_conds(ir_node *irn, unsigned long visited_nr,
                ir_node *dominator, ir_node *masked_by, int pos, int depth, set *conds)
 {
        ir_node *block;
@@ -384,10 +384,6 @@ static void _find_conds(ir_node *irn, ir_node *start_block,
                ir_node *cond = NULL;
                int i, n;
 
-               /* We ran into a loop, since we saw the start block twice. */
-               if(block == start_block && depth > 0)
-                       return;
-
                /* check, if we're on a ProjX */
                if(is_Proj(irn) && get_irn_mode(irn) == mode_X) {
 
@@ -433,17 +429,27 @@ static void _find_conds(ir_node *irn, ir_node *start_block,
                        }
                }
 
-               /* Search recursively from this cond. */
-               for(i = 0, n = get_irn_arity(block); i < n; ++i) {
-                       ir_node *pred = get_irn_n(block, i);
+               /*
+                * If this block has already been visited, don't recurse to its
+                * children.
+                */
+               if(get_irn_visited(block) < visited_nr) {
 
-                       /*
-                        * If the depth is 0 (the first recursion), we set the pos to
-                        * the current viewed predecessor, else we adopt the position
-                        * as given by the caller. We also increase the depth for the
-                        * recursively called functions.
-                        */
-                       _find_conds(pred, start_block, dominator, cond, depth == 0 ? i : pos, depth + 1, conds);
+                       /* Mark the block visited. */
+                       set_irn_visited(block, visited_nr);
+
+                       /* Search recursively from this cond. */
+                       for(i = 0, n = get_irn_arity(block); i < n; ++i) {
+                               ir_node *pred = get_irn_n(block, i);
+
+                               /*
+                                * If the depth is 0 (the first recursion), we set the pos to
+                                * the current viewed predecessor, else we adopt the position
+                                * as given by the caller. We also increase the depth for the
+                                * recursively called functions.
+                                */
+                               _find_conds(pred, visited_nr, dominator, cond, depth == 0 ? i : pos, depth + 1, conds);
+                       }
                }
        }
 }
@@ -459,7 +465,8 @@ static void _find_conds(ir_node *irn, ir_node *start_block,
  */
 static INLINE void find_conds(ir_node *irn, ir_node *dominator, set *conds)
 {
-       _find_conds(irn, get_nodes_block(irn), dominator, NULL, 0, 0, conds);
+       inc_irg_visited(current_ir_graph);
+       _find_conds(irn, get_irg_visited(current_ir_graph), dominator, NULL, 0, 0, conds);
 }
 
 
@@ -618,7 +625,11 @@ static void check_out_phi(ir_node *irn, opt_if_conv_info_t *info)
         */
        mux = make_mux_on_demand(irn, idom, largest_cond);
 
+       /*
+        * Try to optimize mux chains.
+        */
        mux = optimize_mux_chain(mux);
+
        /*
         * Set all preds of the phi node to the mux
         * for the 'largest' cond.
@@ -640,7 +651,7 @@ static void annotate_cond_info_post(ir_node *irn, void *data)
         * phi's block up to its dominator.
         * The set is attached to the blocks link field.
         */
-       if(is_Phi(irn)) {
+       if(is_Phi(irn) && mode_is_datab(get_irn_mode(irn))) {
                ir_node *block = get_nodes_block(irn);
                ir_node **phi_list_head = (ir_node **) data;