Implement better magic to handle changing control dependencies when welding blocks

[r7798]

diff --git a/ir/opt/ifconv.c b/ir/opt/ifconv.c
index 67e31a7..b7aa9c6 100644 (file)
--- a/ir/opt/ifconv.c
+++ b/ir/opt/ifconv.c
@@ -75,14 +75,14 @@ static ir_node* walk_to_projx(ir_node* start, const ir_node* dependency)
        arity = get_irn_arity(start);
        for (i = 0; i < arity; ++i) {
                ir_node* pred = get_irn_n(start, i);
-               ir_node* pred_block;
+               ir_node* pred_block = get_nodes_block(pred);
 
-               if (is_Proj(pred)) {
+               if (pred_block == dependency) {
+                       assert(is_Proj(pred));
                        assert(get_irn_mode(pred) == mode_X);
                        return pred;
                }
 
-               pred_block = get_nodes_block(pred);
                if (is_cdep_on(pred_block, dependency)) {
                        return walk_to_projx(pred_block, dependency);
                }
@@ -321,9 +321,17 @@ restart:
                                exchange(get_nodes_block(get_irn_n(block, j)), psi_block);
 
                                if (arity == 2) {
+#if 1
+                                       DB((dbg, LEVEL_1,  "Welding block %+F and %+F\n", block, psi_block));
+                                       get_block_blockinfo(block)->has_pinned |=       get_block_blockinfo(psi_block)->has_pinned;
+                                       set_irn_in(block, get_irn_arity(psi_block), get_irn_in(psi_block) + 1);
+                                       exchange_cdep(psi_block, block);
+                                       exchange(psi_block, block);
+#else
                                        DB((dbg, LEVEL_1,  "Welding block %+F to %+F\n", block, psi_block));
                                        get_block_blockinfo(psi_block)->has_pinned |=   get_block_blockinfo(block)->has_pinned;
                                        exchange(block, psi_block);
+#endif
                                        return;
                                } else {
                                        rewire(block, i, j, new_r_Jmp(current_ir_graph, psi_block));