Let foreach_pset() declare its iterator variable.

[libfirm] / ir / opt / cfopt.c

diff --git a/ir/opt/cfopt.c b/ir/opt/cfopt.c
index 49aa772..f681765 100644 (file)
--- a/ir/opt/cfopt.c
+++ b/ir/opt/cfopt.c
@@ -46,7 +46,6 @@
 #include "irdump.h"
 #include "irverify.h"
 #include "iredges.h"
-#include "opt_manage.h"
 
 #include "array_t.h"
 
@@ -234,6 +233,26 @@ non_dispensable:
        return 1;
 }
 
+/**
+ * This method merges blocks. A block is applicable to be merged, if it
+ * has only one predecessor with an unconditional jump to this block;
+ * and if this block does not contain any phis.
+ */
+static void merge_blocks(ir_node *b, void *env)
+{
+       (void) env;
+
+       if (get_Block_n_cfgpreds(b) == 1) {
+               ir_node* pred = get_Block_cfgpred(b, 0);
+               if (is_Jmp(pred)) {
+                       ir_node* pred_block = get_nodes_block(pred);
+                       if (get_Block_phis(b) == NULL) {
+                               exchange(b, pred_block);
+                       }
+               }
+       }
+}
+
 /**
  * This method removes empty blocks.  A block is empty if it only contains Phi
  * and Jmp nodes.
@@ -789,12 +808,13 @@ static void cfgopt_ignoring_phis(ir_graph *irg)
                irg_block_walk_graph(irg, NULL, optimize_ifs, &env);
 
                if (env.changed) {
-                       clear_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE);
+                       confirm_irg_properties(irg, IR_GRAPH_PROPERTIES_NONE);
                        /* clear block info, because it must be recomputed */
                        irg_block_walk_graph(irg, clear_block_info, NULL, &env.block_infos);
                        /* Removing blocks and Conds might enable more optimizations */
                        continue;
                } else {
+                       confirm_irg_properties(irg, IR_GRAPH_PROPERTIES_ALL);
                        break;
                }
        }
@@ -803,7 +823,7 @@ static void cfgopt_ignoring_phis(ir_graph *irg)
 }
 
 /* Optimizations of the control flow that also require changes of Phi nodes.  */
-static ir_graph_state_t do_cfopt(ir_graph *irg)
+void optimize_cf(ir_graph *irg)
 {
        int i, j, n;
        ir_node **in = NULL;
@@ -820,7 +840,7 @@ static ir_graph_state_t do_cfopt(ir_graph *irg)
        assert(get_irg_pinned(irg) != op_pin_state_floats &&
               "Control flow optimization need a pinned graph");
 
-       edges_deactivate(irg);
+       assure_irg_properties(irg, IR_GRAPH_PROPERTY_NO_UNREACHABLE_CODE);
 
        /* First the "simple" optimizations, which do not touch Phis */
        cfgopt_ignoring_phis(irg);
@@ -829,27 +849,13 @@ static ir_graph_state_t do_cfopt(ir_graph *irg)
        ir_reserve_resources(irg, IR_RESOURCE_BLOCK_MARK | IR_RESOURCE_IRN_LINK
                             | IR_RESOURCE_PHI_LIST);
 
-       /* The switch Cond optimization might expose unreachable code, so we loop */
-       for (;;) {
-               bool changed = false;
-
-               assure_doms(irg);
-
-               /*
-                * This pass collects all Phi nodes in a link list in the block
-                * nodes.  Further it performs simple control flow optimizations.
-                * Finally it marks all blocks that do not contain useful
-                * computations, i.e., these blocks might be removed.
-                */
-               irg_walk(end, clear_link_and_mark_blocks_removable, collect_nodes, NULL);
-
-               if (!changed)
-                       break;
-
-               clear_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE
-                                  | IR_GRAPH_STATE_VALID_EXTENDED_BLOCKS
-                                  | IR_GRAPH_STATE_CONSISTENT_ENTITY_USAGE);
-       }
+       /*
+        * This pass collects all Phi nodes in a link list in the block
+        * nodes.  Further it performs simple control flow optimizations.
+        * Finally it marks all blocks that do not contain useful
+        * computations, i.e., these blocks might be removed.
+        */
+       irg_walk(end, clear_link_and_mark_blocks_removable, collect_nodes, NULL);
 
        /* assert due to collect_nodes:
         * 1. removable blocks are now marked as such
@@ -857,11 +863,11 @@ static ir_graph_state_t do_cfopt(ir_graph *irg)
         */
 
        /* Optimize the standard code.
-        * It walks only over block nodes and adapts these and the Phi nodes in these
-        * blocks, which it finds in a linked list computed before.
-        * */
-       assure_doms(irg);
-       irg_block_walk_graph(irg, optimize_blocks, NULL, &env);
+        * It walks only over block nodes and adapts these and the Phi nodes in
+        * these blocks, which it finds in a linked list computed before.
+        */
+       assure_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_DOMINANCE);
+       irg_block_walk_graph(irg, optimize_blocks, merge_blocks, &env);
 
        new_end = optimize_in_place(end);
        if (new_end != end) {
@@ -909,18 +915,8 @@ static ir_graph_state_t do_cfopt(ir_graph *irg)
                }
        }
 
-       return 0;
-}
-
-static optdesc_t opt_cf = {
-       "control-flow",
-       IR_GRAPH_STATE_NO_UNREACHABLE_CODE,
-       do_cfopt,
-};
-
-void optimize_cf(ir_graph *irg)
-{
-       perform_irg_optimization(irg, &opt_cf);
+       confirm_irg_properties(irg,
+               env.changed ? IR_GRAPH_PROPERTIES_NONE : IR_GRAPH_PROPERTIES_ALL);
 }
 
 /* Creates an ir_graph pass for optimize_cf. */