-/* Copyright (C) 1998 - 2001 by Universitaet Karlsruhe
-** All rights reserved.
-**
-** Author: Christian Schaefer, Goetz Lindenmaier
-**
-** Optimizations for a whole ir graph, i.e., a procedure.
-*/
+/*
+ * Project: libFIRM
+ * File name: ir/ir/irgopt.h
+ * Purpose: Optimizations for a whole ir graph, i.e., a procedure.
+ * Author: Christian Schaefer, Goetz Lindenmaier
+ * Modified by: Sebastian Felis
+ * Created:
+ * CVS-ID: $Id$
+ * Copyright: (c) 1998-2003 Universität Karlsruhe
+ * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
+ */
-/* $Id$ */
+/**
+ * @file irgopt.h
+ *
+ * Optimizations for a whole ir graph, i.e., a procedure.
+ *
+ * @author Christian Schaefer, Goetz Lindenmaier
+ */
# ifndef _IRGOPT_H_
# define _IRGOPT_H_
# include "irgraph.h"
-/* Applies local optimizations (see iropt.h) to all nodes in the graph. */
+/** Applies local optimizations (see iropt.h) to all nodes in the graph. */
void local_optimize_graph (ir_graph *irg);
-/* Performs dead node elimination by copying the ir graph to a new obstack.
+/** Performs dead node elimination by copying the ir graph to a new obstack.
+
Further removes Bad predecesors from Blocks and the corresponding
inputs to Phi nodes.
Optimization is only performed if options `optimize' and
`opt_dead_node_elimination' are set.
The graph may not be in state phase_building. The outs datasturcture
- is freed, the outs state set to no_outs. (@@@ Change this? -> inconsistent.)
+ is freed, the outs state set to no_outs.
+ @todo Change this? -> inconsistent.
+
+ Backedge information is conserved.
Removes old attributes of nodes. Sets link field to NULL.
+ Callee information must be freed (irg_callee_info_none).
+
Attention: the numbers assigned to nodes if the library is compiled for
development/debugging are not conserved by copying. */
void dead_node_elimination(ir_graph *irg);
-/* Removes Bad Bad predecesors from Blocks and the corresponding
+/** Removes Bad Bad predecesors from Blocks and the corresponding
inputs to Phi nodes as in dead_node_elimination but without
copying the graph.
- @@@ not implemented! */
+
+ @todo not implemented! */
void remove_bad_predecessors(ir_graph *irg);
-/* Inlines a method at the given call site.
+/** Inlines a method at the given call site.
+
+ Removes the call node and splits the basic block the call node
+ belongs to. Inserts a copy of the called graph between these nodes.
Assumes that call is a Call node in current_ir_graph and that
the type in the Call nodes type attribute is the same as the
type of the called graph.
if they are equal.
Sets visited masterflag in current_ir_graph to the max of the flag in
current and called graph.
- Removes the call node and splits the basic block the call node
- belongs to. Inserts a copy of the called graph between these nodes.
+ Assumes that both, the called and the calling graph are in state
+ "pinned".
It is recommended to call local_optimize_graph after inlining as this
function leaves a set of obscure Tuple nodes, e.g. a Proj-Tuple-Jmp
combination as control flow operation. */
void inline_method(ir_node *call, ir_graph *called_graph);
-
-/* Inlines all small methods at call sites where the called address comes
+/** Inlines all small methods at call sites where the called address comes
from a Const node that references the entity representing the called
method.
The size argument is a rough measure for the code size of the method:
combination as control flow operation. */
void inline_small_irgs(ir_graph *irg, int size);
-/* Code Placement. Pinns all floating nodes to a block where they
+
+/** Inlineing with a different heuristic than inline_small_irgs.
+ *
+ * Inlines leave functions. If inlinening creates new leave
+ * function inlines these, too. (If g calls f, and f calls leave h,
+ * h is first inlined in f and then f in g.)
+ *
+ * Then inlines all small functions (this is not recursive).
+ *
+ * For a heuristic this inlineing uses firm node counts. It does
+ * not count auxiliary nodes as Proj, Tuple, End, Start, Id, Sync.
+ *
+ * maxsize Do not inline any calls if a method has more than
+ * maxsize firm nodes. It may reach this limit by
+ * inlineing.
+ * leavesize Inline leave functions if they have less than leavesize
+ * nodes.
+ * size Inline all function smaller than size.
+ */
+void inline_leave_functions(int maxsize, int leavesize, int size);
+
+/** Code Placement. Pinns all floating nodes to a block where they
will be executed only if needed. Depends on the flag opt_global_cse.
Graph may not be in phase_building. Does not schedule control dead
code. Uses dominator information which it computes if the irg is not
in state dom_consistent. Destroys the out information as it moves nodes
- to other blocks. Optimizes Tuples in Control edges. (@@@ This
- is not tested!)
- @@@ A more powerful code placement would move operations past Phi nodes
- out of loops. Further the control flow should be normalized before
- computing the dominator information so that there exists an optimal block
- for all operations. */
+ to other blocks. Optimizes Tuples in Control edges.
+ @todo This is not tested!
+
+ Call remove_critical_cf_edges() before place_code(). This normalizes
+ the control flow graph so that for all operations a basic block exists
+ where they can be optimally placed.
+
+ @todo A more powerful code placement would move operations past Phi nodes
+ out of loops. */
void place_code(ir_graph *irg);
+/** Control flow optimization.
+ * Removes empty blocks doing if simplifications and loop simplifications.
+ * A block is empty if it contains only a Jmp node and Phi nodes.
+ * Merges single entry single exit blocks with their predecessor
+ * and propagates dead control flow by calling equivalent_node.
+ * Independent of compiler flag it removes Tuples from cf edges,
+ * Bad predecessors form blocks and unnecessary predecessors of End.
+ *
+ * @bug So far destroys backedge information.
+ * @bug Chokes on Id nodes if called in a certain order with other
+ * optimizations. Call local_optimize_graph before to remove
+ * Ids.
+ */
+void optimize_cf(ir_graph *irg);
+/** Places an empty basic block on critical control flow edges thereby
+ removing them.
+ A critical control flow edge is an edge from a block with several
+ control exits to a block with several control entries (See Muchnic
+ p. 407).
+ Is only executed if flag set_opt_critical_edges() is set.
+ @param irg IR Graph
+*/
+void remove_critical_cf_edges(ir_graph *irg);
+
# endif /* _IRGOPT_H_ */
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