X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fir%2Firgopt.h;h=910cbc34d1e253162420cd3f4465503662f39360;hb=f9d25133f86594ca2b1f33fb0b41a591ecc9b914;hp=b444fde8d4ed16ddb066334547f52bae8a320c05;hpb=45a9397451c25fb527c32c87f64ffefc72015c81;p=libfirm diff --git a/ir/ir/irgopt.h b/ir/ir/irgopt.h index b444fde8d..910cbc34d 100644 --- a/ir/ir/irgopt.h +++ b/ir/ir/irgopt.h @@ -1,22 +1,192 @@ -/* Copyright (C) 1998 - 2000 by Universitaet Karlsruhe -** All rights reserved. -** -** Author: Christian Schaefer -** -** dead node elemination -** walks one time through the whole graph and copies it into another graph, -** so unreachable nodes will be lost. -*/ +/* + * 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. + */ + +/** + * @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) 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. */ -void dead_node_elemination(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 + * + * The major intention of this pass is to free memory occupied by + * dead nodes and outdated analyses information.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); + +/** 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. + * 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 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(). + * + * 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. + * + * @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); + +/** 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); + +/** + * Copies a node to the current_ir_graph. The Ins of the new node point to + * the predecessors on the graph of the old node. For block/phi nodes not all + * predecessors might be copied. + * For Phi and Block nodes the function allocates in-arrays with an arity + * only for useful predecessors. The arity is determined by counting + * the non-bad predecessors of the block. + * Does NOT copy Bad nodes, as these are "local" to the graph. + * Use get_irg_bad() instead. + * + * @param n The node to be copied + * @param copy_node_nr if non-NULL, the node number attribute will be copied to the new node + */ +ir_node *copy_irn(ir_node *n, int copy_node_nr); # endif /* _IRGOPT_H_ */