/**
* @file
- * @brief Introduce several copies for one node.
- * @author Sebastian Hack, Daniel Grund, Matthias Braun, Christian Wuerdig
- * @date 30.03.2007
- * @version $Id$
- * Copyright: (c) Universitaet Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
-
+ * @brief SSA construction for a set of nodes
+ * @author Sebastian Hack, Daniel Grund, Matthias Braun, Christian Wuerdig
+ * @date 30.03.2007
+ * @version $Id$
+ *
+ * The problem: Given a value and a set of "copies" that are known to
+ * represent the same abstract value, rewire all usages of the original value
+ * to their closest copy while introducing phis as necessary.
+ *
+ * Algorithm: Mark all blocks in the iterated dominance frontiers of the value
+ * and it's copies. Link the copies ordered by dominance to the blocks. The
+ * we search for each use all all definitions in the current block, if none is
+ * found, then we search one in the immediate dominator. If we are in a block
+ * of the dominance frontier, create a phi and search do the same search for
+ * the phi arguments.
+ *
* A copy in this context means, that you want to introduce several new
* abstract values (in Firm: nodes) for which you know, that they
* represent the same concrete value. This is the case if you
* This function reroutes all uses of the original value to the copies in the
* corresponding dominance subtrees and creates Phi functions where necessary.
*/
-#ifndef FIRM_BE_SSACONSTR_H
-#define FIRM_BE_SSACONSTR_H
+#ifndef FIRM_BE_BESSACONSTR_H
+#define FIRM_BE_BESSACONSTR_H
-#include <stdlib.h>
+#include "firm_types.h"
#include "bedomfront.h"
-#include "irnode.h"
#include "irnodeset.h"
#include "belive.h"
#include "beirg.h"
#include "pdeq.h"
typedef struct be_ssa_construction_env_t {
- ir_graph *irg;
- const be_dom_front_info_t *domfronts;
- ir_mode *mode;
- waitq *worklist;
- const ir_nodeset_t *ignore_uses;
+ ir_graph *irg;
+ const be_dom_front_info_t *domfronts;
+ ir_mode *mode;
+ waitq *worklist;
+ const ir_nodeset_t *ignore_uses;
ir_node **new_phis;
- int iterated_domfront_calculated;
+ int iterated_domfront_calculated;
} be_ssa_construction_env_t;
/**
*/
void be_ssa_construction_destroy(be_ssa_construction_env_t *env);
-#endif
+#endif /* FIRM_BE_BESSACONSTR_H */