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22 * File name: ir/ir/irgopt.h
23 * Purpose: Optimizations for a whole ir graph, i.e., a procedure.
24 * Author: Christian Schaefer, Goetz Lindenmaier
25 * Modified by: Sebastian Felis
28 * Copyright: (c) 1998-2003 Universität Karlsruhe
34 * Optimizations for a whole ir graph, i.e., a procedure.
36 * @author Christian Schaefer, Goetz Lindenmaier
38 #ifndef _FIRM_IR_IRGOPT_H_
39 #define _FIRM_IR_IRGOPT_H_
41 #include "firm_types.h"
43 /** Applies local optimizations (see iropt.h) to all nodes reachable from node n.
45 * @param n The node to be optimized.
47 void local_optimize_node(ir_node *n);
49 /** Applies local optimizations (see iropt.h) to all nodes in the graph.
51 * @param irg The graph to be optimized.
53 * After applying local_optimize_graph() to a IR-graph, Bad nodes
54 * only occure as predecessor of Block and Phi nodes.
56 void local_optimize_graph (ir_graph *irg);
58 /** Applies local optimizations (see iropt.h) to all nodes in the graph.
60 * @param irg The graph to be optimized.
62 * After applying local_optimize_graph() to a IR-graph, Bad nodes
63 * only occure as predecessor of Block and Phi nodes.
65 * This version used a fixpoint iteration.
67 void optimize_graph_df(ir_graph *irg);
69 /** Performs dead node elimination by copying the ir graph to a new obstack.
71 * The major intention of this pass is to free memory occupied by
72 * dead nodes and outdated analyzes information. Further this
73 * function removes Bad predecessors from Blocks and the corresponding
74 * inputs to Phi nodes. This opens optimization potential for other
75 * optimizations. Further this phase reduces dead Block<->Jmp
76 * self-cycles to Bad nodes.
78 * Dead_node_elimination is only performed if options `optimize' and
79 * `opt_dead_node_elimination' are set. The graph may
80 * not be in state phase_building. The outs datasturcture is freed,
81 * the outs state set to outs_none. Backedge information is conserved.
82 * Removes old attributes of nodes. Sets link field to NULL.
83 * Callee information must be freed (irg_callee_info_none).
85 * @param irg The graph to be optimized.
87 void dead_node_elimination(ir_graph *irg);
89 typedef struct _survive_dce_t survive_dce_t;
92 * Make a new Survive DCE environment.
94 survive_dce_t *new_survive_dce(void);
97 * Free a Survive DCE environment.
99 void free_survive_dce(survive_dce_t *sd);
102 * Register a node pointer to be patched upon DCE.
103 * When DCE occurs, the node pointer specified by @p place will be
104 * patched to the new address of the node it is pointing to.
106 * @param sd The Survive DCE environment.
107 * @param place The address of the node pointer.
109 void survive_dce_register_irn(survive_dce_t *sd, ir_node **place);
111 /** Cleans the control flow from Bad predecessors.
113 * Removes Bad predecessors from Blocks and the corresponding
114 * inputs to Phi nodes as in dead_node_elimination but without
117 * Conserves loop information.
119 * @param irg The graph to be optimized.
121 void remove_bad_predecessors(ir_graph *irg);
123 /** Inlines a method at the given call site.
125 * Removes the call node and splits the basic block the call node
126 * belongs to. Inserts a copy of the called graph between these nodes.
127 * Assumes that call is a Call node in current_ir_graph and that
128 * the type in the Call nodes type attribute is the same as the
129 * type of the called graph.
130 * Further it assumes that all Phi nodes in a block of current_ir_graph
131 * are assembled in a "link" list in the link field of the corresponding
132 * block nodes. Further assumes that all Proj nodes are in a "link" list
133 * in the nodes producing the tuple. (This is only an optical feature
134 * for the graph.) Conserves this feature for the old
135 * nodes of the graph. This precondition can be established by a call to
136 * collect_phisprojs(), see irgmod.h.
137 * As dead_node_elimination this function reduces dead Block<->Jmp
138 * self-cycles to Bad nodes.
140 * Called_graph must be unequal to current_ir_graph. Will not inline
142 * Sets visited masterflag in current_ir_graph to the max of the flag in
143 * current and called graph.
144 * Assumes that both, the called and the calling graph are in state
145 * "op_pin_state_pinned".
146 * It is recommended to call local_optimize_graph() after inlining as this
147 * function leaves a set of obscure Tuple nodes, e.g. a Proj-Tuple-Jmp
148 * combination as control flow operation.
150 * @param call the call node that should be inlined
151 * @param called_graph the IR-graph that is called at call
153 * @return zero if method could not be inlined (recursion for instance),
154 * non-zero if all went ok
156 int inline_method(ir_node *call, ir_graph *called_graph);
158 /** Inlines all small methods at call sites where the called address comes
159 * from a SymConst node that references the entity representing the called
162 * The size argument is a rough measure for the code size of the method:
163 * Methods where the obstack containing the firm graph is smaller than
164 * size are inlined. Further only a limited number of calls are inlined.
165 * If the method contains more than 1024 inlineable calls none will be
167 * Inlining is only performed if flags `optimize' and `inlineing' are set.
168 * The graph may not be in state phase_building.
169 * It is recommended to call local_optimize_graph() after inlining as this
170 * function leaves a set of obscure Tuple nodes, e.g. a Proj-Tuple-Jmp
171 * combination as control flow operation.
173 void inline_small_irgs(ir_graph *irg, int size);
176 /** Inlineing with a different heuristic than inline_small_irgs().
178 * Inlines leave functions. If inlinening creates new leave
179 * function inlines these, too. (If g calls f, and f calls leave h,
180 * h is first inlined in f and then f in g.)
182 * Then inlines all small functions (this is not recursive).
184 * For a heuristic this inlineing uses firm node counts. It does
185 * not count auxiliary nodes as Proj, Tuple, End, Start, Id, Sync.
186 * If the ignore_runtime flag is set, calls to functions marked with the
187 * mtp_property_runtime property are ignored.
189 * @param maxsize Do not inline any calls if a method has more than
190 * maxsize firm nodes. It may reach this limit by
192 * @param leavesize Inline leave functions if they have less than leavesize
194 * @param size Inline all function smaller than size.
195 * @param ignore_runtime count a function only calling runtime functions as
198 void inline_leave_functions(int maxsize, int leavesize, int size, int ignore_runtime);
202 * Pins all floating nodes to a block where they
203 * will be executed only if needed. Depends on the flag opt_global_cse.
204 * Graph may not be in phase_building. Does not schedule control dead
205 * code. Uses dominator information which it computes if the irg is not
206 * in state dom_consistent. Destroys the out information as it moves nodes
207 * to other blocks. Optimizes Tuples in Control edges.
208 * @todo This is not tested!
210 * Call remove_critical_cf_edges() before place_code(). This normalizes
211 * the control flow graph so that for all operations a basic block exists
212 * where they can be optimally placed.
214 * @todo A more powerful code placement would move operations past Phi nodes
217 void place_code(ir_graph *irg);
219 /** Places an empty basic block on critical control flow edges thereby
222 * A critical control flow edge is an edge from a block with several
223 * control exits to a block with several control entries (See Muchnic
226 * @param irg IR Graph
228 void remove_critical_cf_edges(ir_graph *irg);
230 #endif /* _FIRM_IR_IRGOPT_H_ */