X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fir%2Firgopt.h;h=70b48980a6dd229db87a18dbea585708b91849ac;hb=2853e2e68b316d25973f21292b117a834275a7fd;hp=e66d893020fc877947997559197b11ec0b99d46c;hpb=dddcc630819f338c3b45e2bc646233e6872d5bb6;p=libfirm diff --git a/ir/ir/irgopt.h b/ir/ir/irgopt.h index e66d89302..70b48980a 100644 --- a/ir/ir/irgopt.h +++ b/ir/ir/irgopt.h @@ -25,12 +25,17 @@ /** Applies local optimizations (see iropt.h) to all nodes reachable from node n. * - * @param n The node to be optimized. */ + * @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. */ + * @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. @@ -49,18 +54,40 @@ void local_optimize_graph (ir_graph *irg); * 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. - * - * @param irg The graph to be optimized. */ + * @param irg The graph to be optimized. + */ void dead_node_elimination(ir_graph *irg); +typedef struct _survive_dce_t survive_dce_t; + +/** + * Make a new Survive DCE environment. + */ +survive_dce_t *new_survive_dce(void); + +/** + * Free a Survive DCE environment. + */ +void free_survive_dce(survive_dce_t *sd); + +/** + * 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); + /** 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); @@ -88,7 +115,7 @@ void remove_bad_predecessors(ir_graph *irg); * 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 + * 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. * @@ -97,12 +124,13 @@ void remove_bad_predecessors(ir_graph *irg); * * @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 + * 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. @@ -110,13 +138,14 @@ int inline_method(ir_node *call, ir_graph *called_graph); * 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 + * 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. */ + * 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, @@ -136,46 +165,34 @@ void inline_small_irgs(ir_graph *irg, int 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_ */