/*
-* Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
-*
-* This file is part of libFirm.
-*
-* This file may be distributed and/or modified under the terms of the
-* GNU General Public License version 2 as published by the Free Software
-* Foundation and appearing in the file LICENSE.GPL included in the
-* packaging of this file.
-*
-* Licensees holding valid libFirm Professional Edition licenses may use
-* this file in accordance with the libFirm Commercial License.
-* Agreement provided with the Software.
-*
-* This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
-* WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-* PURPOSE.
-*/
+ * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
+ *
+ * This file is part of libFirm.
+ *
+ * This file may be distributed and/or modified under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation and appearing in the file LICENSE.GPL included in the
+ * packaging of this file.
+ *
+ * Licensees holding valid libFirm Professional Edition licenses may use
+ * this file in accordance with the libFirm Commercial License.
+ * Agreement provided with the Software.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+ * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE.
+ */
/**
-* @file
-* @brief Loop datastructure and access functions.
-* @author Goetz Lindenmaier
-* @date 7.2002
-* @version $Id$
-* @summary
-* Computes backedges in the control and data flow.
-*
-* @note
-* Only Block and Phi/Filter nodes can have incoming backedges.
-* Constructs loops data structure: indicates loop nesting.
-*/
+ * @file
+ * @brief Loop datastructure and access functions.
+ * @author Goetz Lindenmaier
+ * @date 7.2002
+ * @version $Id$
+ * @summary
+ * Computes backedges in the control and data flow.
+ *
+ * @note
+ * Only Block and Phi/Filter nodes can have incoming backedges.
+ * Constructs loops data structure: indicates loop nesting.
+ */
#ifndef FIRM_ANA_IRLOOP_H
#define FIRM_ANA_IRLOOP_H
#include "firm_types.h"
+#include "firm_common.h"
/* ------------------------------------------------------------------- */
/*
-* Backedge information.
-*
-* Predecessors of Block, Phi and interprocedural Filter nodes can
-* have backedges. If loop information is computed, this
-* information is computed, too.
-* The backedge information can only be used if the graph is not in
-* phase phase_building.
-*/
+ * Backedge information.
+ *
+ * Predecessors of Block, Phi and interprocedural Filter nodes can
+ * have backedges. If loop information is computed, this
+ * information is computed, too.
+ * The backedge information can only be used if the graph is not in
+ * phase phase_building.
+ */
/* ------------------------------------------------------------------- */
#ifdef INTERPROCEDURAL_VIEW
/** Loop elements: loop nodes and ir nodes */
typedef union {
firm_kind *kind; /**< is either k_ir_node or k_ir_loop */
- ir_node *node; /**< Pointer to an ir_node element */
- ir_loop *son; /**< Pointer to an ir_loop element */
+ ir_node *node; /**< Pointer to an ir_node element */
+ ir_loop *son; /**< Pointer to an ir_loop element */
+ ir_graph *irg; /**< Pointer to an ir_graph element (only callgraph loop trees) */
} loop_element;
int is_ir_loop(const void *thing);
void set_irg_loop(ir_graph *irg, ir_loop *l);
/* Returns the root loop info (if exists) for an irg. */
-ir_loop *get_irg_loop(ir_graph *irg);
+ir_loop *get_irg_loop(const ir_graph *irg);
/** Returns the loop n is contained in. NULL if node is in no loop. */
ir_loop *get_irn_loop(const ir_node *n);
ir_loop *get_loop_son(ir_loop *loop, int pos);
/** Returns the number of nodes contained in loop. */
-int get_loop_n_nodes(ir_loop *loop);
+int get_loop_n_nodes(const ir_loop *loop);
/** Returns the pos`th ir_node of a loop.
Returns NULL if there is not a pos`th ir_node. */
-ir_node *get_loop_node(ir_loop *loop, int pos);
+ir_node *get_loop_node(const ir_loop *loop, int pos);
/** Returns the number of elements contained in loop. */
int get_loop_n_elements(const ir_loop *loop);
/* ------------------------------------------------------------------- */
/** Constructs backedge information and loop tree for a graph in intraprocedural view.
-*
-* The algorithm views the program representation as a pure graph.
-* It assumes that only block and phi nodes may be loop headers.
-* The resulting loop tree is a possible visiting order for dataflow
-* analysis.
-*
-* This algorithm destoyes the link field of block nodes.
-*
-* @returns Maximal depth of loop tree.
-*
-* @remark
-* One assumes, the Phi nodes in a block with a backedge have backedges
-* at the same positions as the block. This is not the case, as
-* the scc algorithms does not respect the program semantics in this case.
-* Take a swap in a loop (t = i; i = j; j = t;) This results in two Phi
-* nodes. They form a cycle. Once the scc algorithm deleted one of the
-* edges, the cycle is removed. The second Phi node does not get a
-* backedge!
-*/
+ *
+ * The algorithm views the program representation as a pure graph.
+ * It assumes that only block and phi nodes may be loop headers.
+ * The resulting loop tree is a possible visiting order for dataflow
+ * analysis.
+ *
+ * This algorithm destoyes the link field of block nodes.
+ *
+ * @returns Maximal depth of loop tree.
+ *
+ * @remark
+ * One assumes, the Phi nodes in a block with a backedge have backedges
+ * at the same positions as the block. This is not the case, as
+ * the scc algorithms does not respect the program semantics in this case.
+ * Take a swap in a loop (t = i; i = j; j = t;) This results in two Phi
+ * nodes. They form a cycle. Once the scc algorithm deleted one of the
+ * edges, the cycle is removed. The second Phi node does not get a
+ * backedge!
+ */
/* @@@ Well, maybe construct_loop_information or analyze_loops ? */
int construct_backedges(ir_graph *irg);
#ifdef INTERPROCEDURAL_VIEW
/** Constructs backedges for all irgs in interprocedural view.
-*
-* @see As construct_backedges(), but for interprocedural view.
-*
-* @remark
-* All loops in the graph will be marked as such, not only
-* realizeable loops and recursions in the program. E.g., if the
-* same funcion is called twice, there is a loop between the first
-* function return and the second call.
-*
-* @returns Maximal depth of loop tree.
-*/
+ *
+ * @see As construct_backedges(), but for interprocedural view.
+ *
+ * @remark
+ * All loops in the graph will be marked as such, not only
+ * realizeable loops and recursions in the program. E.g., if the
+ * same funcion is called twice, there is a loop between the first
+ * function return and the second call.
+ *
+ * @returns Maximal depth of loop tree.
+ */
int construct_ip_backedges(void);
#endif
-/** Construct loop tree only for control flow.
-*
-* This constructs loop information resembling the program structure.
-* It is useful for loop optimizations and analyses, as, e.g., finding
-* iteration variables or loop invariant code motion.
-*
-* This algorithm computes only back edge information for Block nodes, not
-* for Phi nodes.
-*
-* This algorithm destroyes the link field of block nodes.
-*
-* @returns Maximal depth of loop tree.
-*/
+/**
+ * Construct Intra-procedural control flow loop tree for a IR-graph.
+ *
+ * This constructs loop information resembling the program structure.
+ * It is useful for loop optimizations and analyses, as, e.g., finding
+ * iteration variables or loop invariant code motion.
+ *
+ * This algorithm computes only back edge information for Block nodes, not
+ * for Phi nodes.
+ *
+ * This algorithm destroyes the link field of block nodes.
+ *
+ * @param irg the graph
+ *
+ * @returns Maximal depth of loop tree.
+ */
int construct_cf_backedges(ir_graph *irg);
+/**
+ * Computes Intra-procedural control flow loop tree on demand.
+ *
+ * @param irg the graph
+ */
+void assure_cf_loop(ir_graph *irg);
+
#ifdef INTERPROCEDURAL_VIEW
-/** Construct interprocedural loop tree for control flow.
-*
-* @see construct_cf_backedges() and construct_ip_backedges().
-*/
-int construct_ip_cf_backedges (void);
+/**
+ * Construct Inter-procedural control flow loop tree.
+ *
+ * @see construct_cf_backedges() and construct_ip_backedges().
+ */
+int construct_ip_cf_backedges(void);
#endif
-/** Removes all loop information.
-* Resets all backedges. Works for any construction algorithm.
-*/
+/**
+ * Removes all loop information.
+ * Resets all backedges. Works for any construction algorithm.
+ */
void free_loop_information(ir_graph *irg);
void free_all_loop_information (void);
/* ------------------------------------------------------------------- */
/** Test whether a value is loop invariant.
-*
-* @param n The node to be tested.
-* @param block A block node.
-*
-* Returns non-zero, if the node n is not changed in the loop block
-* belongs to or in inner loops of this block. */
-int is_loop_invariant(ir_node *n, ir_node *block);
+ *
+ * @param n The node to be tested.
+ * @param block A block node.
+ *
+ * Returns non-zero, if the node n is not changed in the loop block
+ * belongs to or in inner loops of this block. */
+int is_loop_invariant(const ir_node *n, const ir_node *block);
#endif