X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fir%2Firgopt.h;h=70b48980a6dd229db87a18dbea585708b91849ac;hb=2853e2e68b316d25973f21292b117a834275a7fd;hp=e85fd4e6548c0eba606c8c8956dfad8886c87ad3;hpb=bbba4631276380ff7e88dbc70a3b8fb89cb96899;p=libfirm diff --git a/ir/ir/irgopt.h b/ir/ir/irgopt.h index e85fd4e65..70b48980a 100644 --- a/ir/ir/irgopt.h +++ b/ir/ir/irgopt.h @@ -23,76 +23,129 @@ # include "irgraph.h" -/** Applies local optimizations (see iropt.h) to all nodes in the graph. */ +/** Applies local optimizations (see iropt.h) to all nodes reachable from node n. + * + * @param n The node to be optimized. + */ +void local_optimize_node(ir_node *n); + +/** Applies local optimizations (see iropt.h) to all nodes in the graph. + * + * @param irg The graph to be optimized. + * + * After applying local_optimize_graph() to a IR-graph, Bad nodes + * only occure as predecessor of Block and Phi nodes. + */ void local_optimize_graph (ir_graph *irg); /** Performs dead node elimination by copying the ir graph to a new obstack. + * + * The major intention of this pass is to free memory occupied by + * dead nodes and outdated analyses information. Further this + * function removes Bad predecesors from Blocks and the corresponding + * inputs to Phi nodes. This opens optmization potential for other + * optimizations. Further this phase reduces dead Block<->Jmp + * self-cycles to Bad nodes. + * + * Dead_node_elimination 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 outs_none. Backedge information is conserved. + * Removes old attributes of nodes. Sets link field to NULL. + * Callee information must be freed (irg_callee_info_none). + * + * @param irg The graph to be optimized. + */ +void dead_node_elimination(ir_graph *irg); - 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. - @todo Change this? -> inconsistent. +typedef struct _survive_dce_t survive_dce_t; - Backedge information is conserved. - Removes old attributes of nodes. Sets link field to NULL. - Callee information must be freed (irg_callee_info_none). +/** + * Make a new Survive DCE environment. + */ +survive_dce_t *new_survive_dce(void); - 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); +/** + * Free a Survive DCE environment. + */ +void free_survive_dce(survive_dce_t *sd); -/** Removes Bad Bad predecesors from Blocks and the corresponding - inputs to Phi nodes as in dead_node_elimination but without - copying the graph. +/** + * Register a node pointer to be patched upon DCE. + * When DCE occurs, the node pointer specified by @p place will be + * patched to the new address of the node it is pointing to. + * + * @param sd The Survive DCE environment. + * @param place The address of the node pointer. + */ +void survive_dce_register_irn(survive_dce_t *sd, ir_node **place); - @todo not implemented! */ +/** Cleans the control flow from Bad predecesors. + * + * Removes Bad predecesors from Blocks and the corresponding + * inputs to Phi nodes as in dead_node_elimination but without + * copying the graph. + * + * Conserves loop information. + * + * @param irg The graph to be optimized. + */ void remove_bad_predecessors(ir_graph *irg); /** 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. - Further it assumes that all Phi nodes in a block of current_ir_graph - are assembled in a "link" list in the link field of the corresponding - block nodes. Further assumes that all Proj nodes are in a "link" list - in the nodes producing the tuple. (This is only an optical feature - for the graph.) Conserves this feature for the old - nodes of the graph. This precondition can be established by a call to - collect_phisprojs(), see irgmod.h. - Called_graph must be unequal to current_ir_graph. Will not inline - if they are equal. - Sets visited masterflag in current_ir_graph to the max of the flag in - current and called graph. - 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); + * + * 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. + * Further it assumes that all Phi nodes in a block of current_ir_graph + * are assembled in a "link" list in the link field of the corresponding + * block nodes. Further assumes that all Proj nodes are in a "link" list + * in the nodes producing the tuple. (This is only an optical feature + * for the graph.) Conserves this feature for the old + * nodes of the graph. This precondition can be established by a call to + * collect_phisprojs(), see irgmod.h. + * As dead_node_elimination this function reduces dead Block<->Jmp + * self-cycles to Bad nodes. + * + * Called_graph must be unequal to current_ir_graph. Will not inline + * if they are equal. + * Sets visited masterflag in current_ir_graph to the max of the flag in + * current and called graph. + * Assumes that both, the called and the calling graph are in state + * "op_pin_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. + * + * @param call the call node that should be inlined + * @param called_graph the IR-graph that is called at call + * + * @return zero if method could not be inlined (recursion for instance), + * non-zero if all went ok + */ +int inline_method(ir_node *call, ir_graph *called_graph); /** 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: - Methods where the obstack containing the firm graph is smaller than - size are inlined. Further only a limited number of calls are inlined. - If the method contains more than 1024 inlineable calls none will be - inlined. - Inlining is only performed if flags `optimize' and `inlineing' are set. - The graph may not be in state phase_building. - 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. */ + * from a SymConst node that references the entity representing the called + * method. + * + * The size argument is a rough measure for the code size of the method: + * Methods where the obstack containing the firm graph is smaller than + * size are inlined. Further only a limited number of calls are inlined. + * If the method contains more than 1024 inlineable calls none will be + * inlined. + * Inlining is only performed if flags `optimize' and `inlineing' are set. + * The graph may not be in state phase_building. + * 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_small_irgs(ir_graph *irg, int size); -/** Inlineing with a different heuristic than inline_small_irgs. +/** 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, @@ -103,55 +156,43 @@ void inline_small_irgs(ir_graph *irg, int size); * 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. + * @param maxsize Do not inline any calls if a method has more than + * maxsize firm nodes. It may reach this limit by + * inlineing. + * @param leavesize Inline leave functions if they have less than leavesize + * nodes. + * @param 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. - @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. +/** Code Placement. + * + * Pins 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. + * @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 optimize_cf(ir_graph *irg); - +void place_code(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 -*/ + * 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). + * + * @param irg IR Graph + */ void remove_critical_cf_edges(ir_graph *irg); # endif /* _IRGOPT_H_ */