3 * File name: ir/ir/irgopt.h
4 * Purpose: Optimizations for a whole ir graph, i.e., a procedure.
5 * Author: Christian Schaefer, Goetz Lindenmaier
6 * Modified by: Sebastian Felis
9 * Copyright: (c) 1998-2003 Universität Karlsruhe
10 * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
16 * Optimizations for a whole ir graph, i.e., a procedure.
18 * @author Christian Schaefer, Goetz Lindenmaier
20 #ifndef _FIRM_IR_IRGOPT_H_
21 #define _FIRM_IR_IRGOPT_H_
23 #include "firm_types.h"
25 /** Applies local optimizations (see iropt.h) to all nodes reachable from node n.
27 * @param n The node to be optimized.
29 void local_optimize_node(ir_node *n);
31 /** Applies local optimizations (see iropt.h) to all nodes in the graph.
33 * @param irg The graph to be optimized.
35 * After applying local_optimize_graph() to a IR-graph, Bad nodes
36 * only occure as predecessor of Block and Phi nodes.
38 void local_optimize_graph (ir_graph *irg);
40 /** Applies local optimizations (see iropt.h) to all nodes in the graph.
42 * @param irg The graph to be optimized.
44 * After applying local_optimize_graph() to a IR-graph, Bad nodes
45 * only occure as predecessor of Block and Phi nodes.
47 * This version used a fixpoint iteration.
49 void optimize_graph_df(ir_graph *irg);
51 /** Performs dead node elimination by copying the ir graph to a new obstack.
53 * The major intention of this pass is to free memory occupied by
54 * dead nodes and outdated analyzes information. Further this
55 * function removes Bad predecessors from Blocks and the corresponding
56 * inputs to Phi nodes. This opens optimization potential for other
57 * optimizations. Further this phase reduces dead Block<->Jmp
58 * self-cycles to Bad nodes.
60 * Dead_node_elimination is only performed if options `optimize' and
61 * `opt_dead_node_elimination' are set. The graph may
62 * not be in state phase_building. The outs datasturcture is freed,
63 * the outs state set to outs_none. Backedge information is conserved.
64 * Removes old attributes of nodes. Sets link field to NULL.
65 * Callee information must be freed (irg_callee_info_none).
67 * @param irg The graph to be optimized.
69 void dead_node_elimination(ir_graph *irg);
71 typedef struct _survive_dce_t survive_dce_t;
74 * Make a new Survive DCE environment.
76 survive_dce_t *new_survive_dce(void);
79 * Free a Survive DCE environment.
81 void free_survive_dce(survive_dce_t *sd);
84 * Register a node pointer to be patched upon DCE.
85 * When DCE occurs, the node pointer specified by @p place will be
86 * patched to the new address of the node it is pointing to.
88 * @param sd The Survive DCE environment.
89 * @param place The address of the node pointer.
91 void survive_dce_register_irn(survive_dce_t *sd, ir_node **place);
93 /** Cleans the control flow from Bad predecessors.
95 * Removes Bad predecessors from Blocks and the corresponding
96 * inputs to Phi nodes as in dead_node_elimination but without
99 * Conserves loop information.
101 * @param irg The graph to be optimized.
103 void remove_bad_predecessors(ir_graph *irg);
105 /** Inlines a method at the given call site.
107 * Removes the call node and splits the basic block the call node
108 * belongs to. Inserts a copy of the called graph between these nodes.
109 * Assumes that call is a Call node in current_ir_graph and that
110 * the type in the Call nodes type attribute is the same as the
111 * type of the called graph.
112 * Further it assumes that all Phi nodes in a block of current_ir_graph
113 * are assembled in a "link" list in the link field of the corresponding
114 * block nodes. Further assumes that all Proj nodes are in a "link" list
115 * in the nodes producing the tuple. (This is only an optical feature
116 * for the graph.) Conserves this feature for the old
117 * nodes of the graph. This precondition can be established by a call to
118 * collect_phisprojs(), see irgmod.h.
119 * As dead_node_elimination this function reduces dead Block<->Jmp
120 * self-cycles to Bad nodes.
122 * Called_graph must be unequal to current_ir_graph. Will not inline
124 * Sets visited masterflag in current_ir_graph to the max of the flag in
125 * current and called graph.
126 * Assumes that both, the called and the calling graph are in state
127 * "op_pin_state_pinned".
128 * It is recommended to call local_optimize_graph() after inlining as this
129 * function leaves a set of obscure Tuple nodes, e.g. a Proj-Tuple-Jmp
130 * combination as control flow operation.
132 * @param call the call node that should be inlined
133 * @param called_graph the IR-graph that is called at call
135 * @return zero if method could not be inlined (recursion for instance),
136 * non-zero if all went ok
138 int inline_method(ir_node *call, ir_graph *called_graph);
140 /** Inlines all small methods at call sites where the called address comes
141 * from a SymConst node that references the entity representing the called
144 * The size argument is a rough measure for the code size of the method:
145 * Methods where the obstack containing the firm graph is smaller than
146 * size are inlined. Further only a limited number of calls are inlined.
147 * If the method contains more than 1024 inlineable calls none will be
149 * Inlining is only performed if flags `optimize' and `inlineing' are set.
150 * The graph may not be in state phase_building.
151 * It is recommended to call local_optimize_graph() after inlining as this
152 * function leaves a set of obscure Tuple nodes, e.g. a Proj-Tuple-Jmp
153 * combination as control flow operation.
155 void inline_small_irgs(ir_graph *irg, int size);
158 /** Inlineing with a different heuristic than inline_small_irgs().
160 * Inlines leave functions. If inlinening creates new leave
161 * function inlines these, too. (If g calls f, and f calls leave h,
162 * h is first inlined in f and then f in g.)
164 * Then inlines all small functions (this is not recursive).
166 * For a heuristic this inlineing uses firm node counts. It does
167 * not count auxiliary nodes as Proj, Tuple, End, Start, Id, Sync.
168 * If the ignore_runtime flag is set, calls to functions marked with the
169 * mtp_property_runtime property are ignored.
171 * @param maxsize Do not inline any calls if a method has more than
172 * maxsize firm nodes. It may reach this limit by
174 * @param leavesize Inline leave functions if they have less than leavesize
176 * @param size Inline all function smaller than size.
177 * @param ignore_runtime count a function only calling runtime functions as
180 void inline_leave_functions(int maxsize, int leavesize, int size, int ignore_runtime);
184 * Pins all floating nodes to a block where they
185 * will be executed only if needed. Depends on the flag opt_global_cse.
186 * Graph may not be in phase_building. Does not schedule control dead
187 * code. Uses dominator information which it computes if the irg is not
188 * in state dom_consistent. Destroys the out information as it moves nodes
189 * to other blocks. Optimizes Tuples in Control edges.
190 * @todo This is not tested!
192 * Call remove_critical_cf_edges() before place_code(). This normalizes
193 * the control flow graph so that for all operations a basic block exists
194 * where they can be optimally placed.
196 * @todo A more powerful code placement would move operations past Phi nodes
199 void place_code(ir_graph *irg);
201 /** Places an empty basic block on critical control flow edges thereby
204 * A critical control flow edge is an edge from a block with several
205 * control exits to a block with several control entries (See Muchnic
208 * @param irg IR Graph
210 void remove_critical_cf_edges(ir_graph *irg);
212 #endif /* _FIRM_IR_IRGOPT_H_ */