X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fana%2Fcgana.c;h=a4052fadef085d893a14f9e35e39270b830bb65e;hb=b451899be294500fe974c6e97febc59cabdda114;hp=ae09efcc3872b072755a1715b790219473328a68;hpb=06f46cfcf9e018ca5d0c735e7192f4e01fc0379b;p=libfirm diff --git a/ir/ana/cgana.c b/ir/ana/cgana.c index ae09efcc3..a4052fade 100644 --- a/ir/ana/cgana.c +++ b/ir/ana/cgana.c @@ -1,32 +1,40 @@ /* - * Project: libFIRM - * File name: ir/ana/cgana.c - * Purpose: Intraprozedural analyses to estimate the call graph. - * Author: Hubert Schmid - * Modified by: - * Created: 09.06.2002 - * CVS-ID: $Id$ - * Copyright: (c) 1999-2003 Universität Karlsruhe - * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE. + * Copyright (C) 1995-2011 University of Karlsruhe. All right reserved. + * + * This file is part of libFirm. + * + * This file may be distributed and/or modified under the terms of the + * GNU General Public License version 2 as published by the Free Software + * Foundation and appearing in the file LICENSE.GPL included in the + * packaging of this file. + * + * Licensees holding valid libFirm Professional Edition licenses may use + * this file in accordance with the libFirm Commercial License. + * Agreement provided with the Software. + * + * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE + * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE. */ /** - * @file cgana.c - * Intraprozedurale Analyse zur Abschätzung der Aufrufrelation. Es - * wird eine Menge von freien Methoden und anschließend die an den - * Call-Operationen aufrufbaren Methoden bestimmt. + * @file + * @brief Intraprozedural analyses to estimate the call graph. + * @author Hubert Schmid + * @date 09.06.2002 + * @brief + * Interprocedural analysis to estimate the calling relation. * + * This analysis computes all entities representing methods that + * can be called at a Call node. Further it computes a set of + * methods that are 'free', i.e., their adress is handled by + * the program directly, or they are visible external. */ -#ifdef HAVE_CONFIG_H -# include "config.h" -#endif +#include "config.h" -#ifdef HAVE_STRING_H -# include -#endif +#include #include "cgana.h" -#include "rta.h" #include "xmalloc.h" #include "irnode_t.h" @@ -35,849 +43,794 @@ #include "irgwalk.h" #include "ircons.h" #include "irgmod.h" +#include "iropt.h" +#include "irtools.h" #include "irflag_t.h" #include "dbginfo_t.h" #include "iropt_dbg.h" -#include "eset.h" #include "pmap.h" #include "array.h" +#include "error.h" #include "irdump.h" -#include "firmstat.h" - -/* Eindeutige Adresse zur Markierung von besuchten Knoten und zur - * Darstellung der unbekannten Methode. */ -static void * MARK = &MARK; - +/* unambiguous address used as a mark. */ +static void *MARK = &MARK; +static pset *entities = NULL; -/* --- sel methods ---------------------------------------------------------- */ +/*--------------------------------------------------------------------------*/ +/* The analysis */ +/*--------------------------------------------------------------------------*/ -static eset * entities = NULL; - - -/** Bestimmt die eindeutige Methode, die die Methode für den - * übergebenen (dynamischen) Typ überschreibt. */ -static entity * get_implementation(type * class, entity * method) { - int i; - if (get_entity_peculiarity(method) != peculiarity_description && - get_entity_owner(method) == class) { - return method; - } - for (i = get_entity_n_overwrittenby(method) - 1; i >= 0; --i) { - entity * e = get_entity_overwrittenby(method, i); - if (get_entity_peculiarity(e) != peculiarity_description && get_entity_owner(e) == class) { - return e; - } - } - for (i = get_class_n_supertypes(class) - 1; i >= 0; --i) { - entity * e = get_implementation(get_class_supertype(class, i), method); - if (e) { - return e; - } - } - assert(0 && "implementation not found"); - return NULL; -} - -/** Returns the entity that contains the implementation of the inherited - entity if available, else returns the entity passed. */ -static entity *get_inherited_methods_implementation(entity *inh_meth) { - assert(get_atomic_ent_value(inh_meth) && "constant entity without value"); - assert((get_irn_op(get_atomic_ent_value(inh_meth)) == op_SymConst) && - (get_SymConst_kind(get_atomic_ent_value(inh_meth)) == symconst_addr_ent) && - "Complex constant values not supported -- address of method should be straight constant!"); - - return get_SymConst_entity(get_atomic_ent_value(inh_meth)); - -#if 0 // this stuff is outdated, I think. GL 10.11.04 - entity *impl_meth = NULL; - ir_node *addr = get_atomic_ent_value(inh_meth); - - assert(get_atomic_ent_value(inh_meth) && "constant entity without value"); - - if ((get_irn_op(addr) == op_SymConst) && - (get_SymConst_kind(addr) == symconst_addr_ent)) { - impl_meth = get_SymConst_entity(addr); - } else { - assert(0 && "Complex constant values not supported -- address of method should be straight constant!"); - } - - if (impl_meth && (get_entity_peculiarity(impl_meth) != peculiarity_existent)) { - /* - printf("this_meth: "); DDMEO(inh_meth); - printf("impl meth: "); DDMEO(impl_meth); - assert(!impl_meth || get_entity_peculiarity(impl_meth) == peculiarity_existent); - */ - assert(0); - impl_meth = NULL; - } - assert((impl_meth || inh_meth) && "no implementation for inherited entity"); - return impl_meth? impl_meth : inh_meth; -#endif -} - +/*--------------------------------------------------------------------------*/ +/* Initialize datastructures, remove unwanted constructs, optimize */ +/* call target computations. */ +/*--------------------------------------------------------------------------*/ /** Collect the entity representing the implementation of this - * entity (not the same if inherited) and all entities for overwriting - * implementations in "set". - * If the implementation of the method is not included in the - * compilation unit "open" is set to true. + * method (not the same if inherited) and all entities for overwriting + * implementations in parameter set. * A recursive descend in the overwritten relation. * Cycle-free, therefore must terminate. * - * @param method + * @param method the overwritten method * @param set A set of entities. - * @param size Number of entities in set. - * @param open + * + * @return Number of entities in set. */ -static void collect_impls(entity *method, eset *set, int *size, bool *open) { - int i; - entity *impl; - -#if 0 - if (get_entity_peculiarity(method) == peculiarity_existent) { - if ((get_entity_visibility(method) == visibility_external_allocated) - && (NULL == get_entity_irg(method))) { - /* We could also add these entities to the callees, but right now we - subsume them by unknown_entity. */ - *open = true; - } else { - assert(get_entity_irg(method) != NULL); - if (!eset_contains(set, method)) { - eset_insert(set, method); - ++(*size); - } - } - } - - if (get_entity_peculiarity(method) == peculiarity_inherited) { - entity *impl_ent = get_inherited_methods_implementation(method); - if (get_entity_visibility(impl_ent) == visibility_external_allocated) { - assert(get_entity_irg(impl_ent) == NULL); - *open = true; - } else { - assert(get_entity_irg(impl_ent) != NULL); - if (!eset_contains(set, impl_ent)) { - eset_insert(set, impl_ent); - ++(*size); - } - } - } -#endif - /* Only the assertions: */ - if (get_entity_peculiarity(method) == peculiarity_existent) { - if ((get_entity_visibility(method) == visibility_external_allocated) - && (NULL == get_entity_irg(method))) { - } else { - assert(get_entity_irg(method) != NULL); - } - } - if (get_entity_peculiarity(method) == peculiarity_inherited) { - entity *impl_ent = get_inherited_methods_implementation(method); - if (get_entity_visibility(impl_ent) == visibility_external_allocated) { - assert(get_entity_irg(impl_ent) == NULL); - } else { - assert(get_entity_irg(impl_ent) != NULL); - } - } - - /* Add the implementation to the set if it contains an irg, else - remember that there are more methods called. */ - /* @@@ We could also add unknown_entity, or the entities with the - unknown irgs. The first case would result in the exact same - behavior: all unknown irgs are represented by the one and only - unknown entity. If we add all entities, we known the number of - entities possibly called, and whether there are real unknown - entities, i.e, such not represented in the type description. - This would be better for an analysis: it could rule out more - cases. */ - impl = method; - if (get_entity_peculiarity(method) == peculiarity_inherited) - impl = get_inherited_methods_implementation(method); - - if (get_entity_peculiarity(method) != peculiarity_description) { - //if (get_entity_irg(impl)) { - eset_insert(set, impl); - ++(*size); - //} else { - /* GL: better: eset_insert(set, unknown_entity); */ - //*open = true; - //} - } - - /*- recursive descent -*/ - for (i = get_entity_n_overwrittenby(method) - 1; i >= 0; --i) - collect_impls(get_entity_overwrittenby(method, i), set, size, open); +static size_t collect_impls(ir_entity *method, pset *set) +{ + size_t i; + size_t size = 0; + + if (get_entity_irg(method) != NULL) { + /* has an implementation */ + pset_insert_ptr(set, method); + ++size; + } + + /*- recursive descent -*/ + for (i = get_entity_n_overwrittenby(method); i > 0;) + size += collect_impls(get_entity_overwrittenby(method, --i), set); + return size; } - -/** Alle Methoden bestimmen, die die übergebene Methode überschreiben - * (und implementieren). In der zurückgegebenen Reihung kommt jede - * Methode nur einmal vor. Der Wert 'NULL' steht für unbekannte - * (externe) Methoden. Die zurückgegebene Reihung muß vom Aufrufer - * wieder freigegeben werden (siehe "DEL_ARR_F"). Gibt es überhaupt - * keine Methoden, die "method" überschreiben, so gibt die Methode - * "NULL" zurück. +/** + * Determine all methods that overwrite the given method (and implement it). + * The returned array must be freed by the caller (see DEL_ARR_F). + * If the set of overwriting methods is empty, returns NULL. * - * @param method + * @param method the method */ -static entity ** get_impl_methods(entity * method) { - eset * set = eset_create(); - int size = 0; - entity ** arr; - bool open = false; - - /* Collect all method entities that can be called here */ - collect_impls(method, set, &size, &open); - - /* Vorgaenger einfuegen. */ - if (size == 0 && !open) { - /* keine implementierte überschriebene Methode */ - arr = NULL; - } else if (open) { - entity * ent; - arr = NEW_ARR_F(entity *, size + 1); - arr[0] = NULL; /* Represents open method */ - for (ent = eset_first(set); size > 0; ent = eset_next(set), --size) - arr[size] = ent; - } else { - entity * ent; - arr = NEW_ARR_F(entity *, size); - for (size -= 1, ent = eset_first(set); size >= 0; ent = eset_next(set), --size) - arr[size] = ent; - } - eset_destroy(set); - return arr; +static ir_entity **get_impl_methods(ir_entity *method) +{ + ir_entity **arr; + pset *set = pset_new_ptr_default(); + size_t size; + + /* Collect all method entities that can be called here */ + size = collect_impls(method, set); + + if (size == 0) { + /* no overwriting methods found */ + arr = NULL; + } else { + arr = NEW_ARR_F(ir_entity *, size); + foreach_pset(set, ir_entity, ent) { + arr[--size] = ent; + } + } + del_pset(set); + return arr; } /** Analyze address computations. * + * Compute for all Sel nodes the set of methods that can be selected. + * For each entity we store the set of subentities in the link field. + * + * Further do some optimizations: + * - Call standard optimizations for Sel nodes: this removes polymorphic + * calls. * - If the node is a SymConst(name) replace it by SymConst(ent) if possible. + * For this we precomputed a map name->entity. Nowadays, we no more support + * this and assert. * - If the node is a Sel: - * * If the pointer to the Sel comes directly from an Alloc node - * replace the Sel by a SymConst(ent). + * If we found only a single method that can be called, replace the Sel + * by a SymConst. This is more powerful than the analysis in opt_polymorphy, + * as here we walk the type graph. In opt_polymorphy we only apply a local + * pattern. * - * - * @param node The node to analyze - * @param env A map that maps names of entities to the entities. + * @param node The node to analyze + * @param env A map that maps names of entities to the entities. */ -static void sel_methods_walker(ir_node * node, void *env) { - pmap *ldname_map = env; - - /* replace SymConst(name)-operations by SymConst(ent) */ - if (get_irn_op(node) == op_SymConst) { - if (get_SymConst_kind(node) == symconst_addr_name) { - pmap_entry * entry = pmap_find(ldname_map, (void *) get_SymConst_name(node)); - if (entry != NULL) { /* Method is declared in the compiled code */ - entity * ent = entry->value; - if (get_opt_normalize() && (get_entity_visibility(ent) != visibility_external_allocated)) { /* Meth. is defined */ - ir_node *new_node; - - set_irg_current_block(current_ir_graph, get_nodes_block(node)); - new_node = copy_const_value(get_atomic_ent_value(ent)); - - DBG_OPT_CSTEVAL(node, new_node); - - assert(get_entity_irg(ent)); - DDMN(new_node); - exchange(node, new_node); - } - } - } - } - else if (get_irn_op(node) == op_Sel && - is_method_type(get_entity_type(get_Sel_entity(node)))) { - entity * ent = get_Sel_entity(node); - - /* Sel from Alloc: replace by constant */ - if (get_opt_optimize() && get_opt_dyn_meth_dispatch() && - (get_irn_op(skip_Proj(get_Sel_ptr(node))) == op_Alloc)) { - ir_node *new_node; - entity *called_ent; - - /* We know which method will be called, no dispatch necessary. */ - called_ent = resolve_ent_polymorphy(get_Alloc_type(skip_Proj(get_Sel_ptr(node))), ent); - set_irg_current_block(current_ir_graph, get_nodes_block(node)); - - /* called_ent may not be description: has no Address/Const to Call! */ - assert(get_entity_peculiarity(called_ent) != peculiarity_description); - new_node = copy_const_value(get_atomic_ent_value(called_ent)); - - DBG_OPT_POLY_ALLOC(node, new_node); - exchange(node, new_node); - } - else { - assert(get_entity_peculiarity(ent) != peculiarity_inherited); - if (!eset_contains(entities, ent)) { - /* Entity noch nicht behandelt. Alle (intern oder extern) - * implementierten Methoden suchen, die diese Entity - * überschreiben. Die Menge an entity.link speichern. */ - set_entity_link(ent, get_impl_methods(ent)); - eset_insert(entities, ent); - } - if (get_entity_link(ent) == NULL) { - /* Die Sel-Operation kann nie einen Zeiger auf eine aufrufbare - * Methode zurückgeben. Damit ist sie insbesondere nicht - * ausführbar und nicht erreichbar. */ - /* Gib eine Warnung aus wenn die Entitaet eine Beschreibung ist - fuer die es keine Implementierung gibt. */ - if (get_entity_peculiarity(ent) == peculiarity_description) { - /* This is possible: We call a method in a dead part of the program. */ - } else { - DDMN(node); - assert(0); /* Why should this happen ??? */ - //exchange(node, new_Bad()); - } - } else { - entity ** arr = get_entity_link(ent); - +static void sel_methods_walker(ir_node *node, void *env) +{ + ir_entity **arr; + (void)env; + + /* Call standard optimizations */ + if (is_Sel(node)) { + ir_node *new_node = optimize_in_place(node); + if (node != new_node) { + exchange(node, new_node); + node = new_node; + } + } + + if (is_Sel(node) && is_Method_type(get_entity_type(get_Sel_entity(node)))) { + ir_entity *ent = get_SymConst_entity(get_atomic_ent_value(get_Sel_entity(node))); + + if (!pset_find_ptr(entities, ent)) { + /* Entity not yet handled. Find all (internal or external) + * implemented methods that overwrites this entity. + * This set is stored in the entity link. */ + set_entity_link(ent, get_impl_methods(ent)); + pset_insert_ptr(entities, ent); + } + + /* -- As an add on we get an optimization that removes polymorphic calls. + This optimization is more powerful than that in transform_node_Sel(). -- */ + arr = (ir_entity**) get_entity_link(ent); + if (arr == NULL) { + /* + * The Sel node never returns a pointer to a usable method. + * We could not call it, but it may be description: + * We call a method in a dead part of the program. + */ + assert(get_entity_irg(ent) == NULL); + } #if 0 - int i; - printf("\nCall site "); DDMN(node); - printf(" in "); DDME(get_irg_entity(current_ir_graph)); - printf(" can call:\n"); - for (i = 0; i < ARR_LEN(arr); i++) { - printf(" - "); DDME(arr[i]); - printf(" with owner "); DDMT(get_entity_owner(arr[i])); - } - printf("\n"); + else if (get_opt_closed_world() && get_opt_dyn_meth_dispatch() && + (ARR_LEN(arr) == 1 && arr[0] != NULL)) { + ir_node *new_node; + + /* + * The Sel node returns only one possible method. + * So we could replace the Sel node by a SymConst. + * This method must exists. + */ + assert(get_entity_irg(arr[0]) != NULL); + new_node = copy_const_value(get_irn_dbg_info(node), get_atomic_ent_value(arr[0]), get_nodes_block(node)); + DBG_OPT_POLY(node, new_node); + exchange(node, new_node); + } #endif - - if (get_opt_optimize() && get_opt_dyn_meth_dispatch() && - (ARR_LEN(arr) == 1 && arr[0] != NULL)) { - ir_node *new_node; - /* Die Sel-Operation kann immer nur _einen_ Wert auf eine - * interne Methode zurückgeben. Wir können daher die - * Sel-Operation durch eine Const- bzw. SymConst-Operation - * ersetzen. */ - set_irg_current_block(current_ir_graph, get_nodes_block(node)); - assert(get_entity_peculiarity(get_SymConst_entity(get_atomic_ent_value(arr[0]))) == - peculiarity_existent); - new_node = copy_const_value(get_atomic_ent_value(arr[0])); - DBG_OPT_POLY(node, new_node); - exchange (node, new_node); - } - } - } - } -} - - -/** Datenstruktur initialisieren. Zusätzlich werden alle - * SymConst(name)-Operationen, die auf interne Methoden verweisen, durch - * SymConst(entity)-Operationen ersetzt. */ -static void sel_methods_init(void) { - int i; - pmap * ldname_map = pmap_create(); /* Map entity names to entities: to replace SymConst(name) by SymConst(ent). */ - - assert(entities == NULL); - entities = eset_create(); - for (i = get_irp_n_irgs() - 1; i >= 0; --i) { - ir_graph *irg = get_irp_irg(i); - entity * ent = get_irg_entity(irg); - /* Nur extern sichtbare Methoden können überhaupt mit SymConst - * aufgerufen werden. */ - if (get_entity_visibility(ent) != visibility_local) { - pmap_insert(ldname_map, (void *) get_entity_ld_ident(ent), ent); - } - } - all_irg_walk(sel_methods_walker, NULL, ldname_map); - pmap_destroy(ldname_map); + } } -/*****************************************************************************/ - -/** Frees the allocated entity map */ -static void sel_methods_dispose(void) { - entity * ent; - assert(entities); - for (ent = eset_first(entities); ent; ent = eset_next(entities)) { - entity ** arr = get_entity_link(ent); - if (arr) { - DEL_ARR_F(arr); - } - set_entity_link(ent, NULL); - } - eset_destroy(entities); - entities = NULL; +/** + * Initialize auxiliary data structures. + * + * Computes a set of entities that overwrite an entity and contain + * an implementation. The set is stored in the entity's link field. + * + * Further replaces Sel nodes where this set contains exactly one + * method by SymConst nodes. + * Finally asserts if there is a SymConst(name) if there could be a + * SymConst(ent). + */ +static void sel_methods_init(void) +{ + size_t i, n; + pmap *ldname_map = pmap_create(); /* Map entity names to entities: to replace + SymConst(name) by SymConst(ent). */ + assert(entities == NULL); + entities = pset_new_ptr_default(); + for (i = 0, n = get_irp_n_irgs(); i < n; ++i) { + ir_entity * ent = get_irg_entity(get_irp_irg(i)); + /* only external visible methods are allowed to call by a SymConst_ptr_name */ + if (entity_is_externally_visible(ent)) { + pmap_insert(ldname_map, (void *)get_entity_ld_ident(ent), ent); + } + } + + all_irg_walk(sel_methods_walker, NULL, NULL); + pmap_destroy(ldname_map); } +/*--------------------------------------------------------------------------*/ +/* Find free methods. + * + * We expect that each entity has an array with all implementations in its + * link field. */ +/*--------------------------------------------------------------------------*/ /** * Returns an array of all methods that could be called at a Sel node. * This array contains every entry only once. + * + * @param sel the Sel node */ -static entity ** get_Sel_arr(ir_node * sel) { - static entity ** NULL_ARRAY = NULL; - entity * ent; - entity ** arr; - - assert(sel && get_irn_op(sel) == op_Sel); - ent = get_Sel_entity(sel); - assert(is_method_type(get_entity_type(ent))); /* what else? */ - arr = get_entity_link(ent); - if (arr) { - return arr; - } else { - /* "NULL" zeigt an, dass keine Implementierung existiert. Dies - * kann für polymorphe (abstrakte) Methoden passieren. */ - if (!NULL_ARRAY) { - NULL_ARRAY = NEW_ARR_F(entity *, 0); - } - return NULL_ARRAY; - } +static ir_entity ** get_Sel_arr(ir_node * sel) +{ + static ir_entity ** NULL_ARRAY = NULL; + ir_entity * ent; + ir_entity ** arr; + + assert(is_Sel(sel)); + ent = get_Sel_entity(sel); + + assert(is_Method_type(get_entity_type(ent))); /* what else? */ + arr = (ir_entity**) get_entity_link(ent); + if (arr) { + return arr; + } else { + /* "NULL" zeigt an, dass keine Implementierung existiert. Dies + * kann f�r polymorphe (abstrakte) Methoden passieren. */ + if (!NULL_ARRAY) { + NULL_ARRAY = NEW_ARR_F(ir_entity *, 0); + } + return NULL_ARRAY; + } } /** * Returns the number of possible called methods at a Sel node. + * + * @param sel the Sel node */ -static int get_Sel_n_methods(ir_node * sel) { - return ARR_LEN(get_Sel_arr(sel)); +static size_t get_Sel_n_methods(ir_node * sel) +{ + return ARR_LEN(get_Sel_arr(sel)); } /** * Returns the ith possible called method entity at a Sel node. */ -static entity * get_Sel_method(ir_node * sel, int pos) { - entity ** arr = get_Sel_arr(sel); - assert(pos >= 0 && pos < ARR_LEN(arr)); - return arr[pos]; +static ir_entity * get_Sel_method(ir_node * sel, size_t pos) +{ + ir_entity ** arr = get_Sel_arr(sel); + assert(pos < ARR_LEN(arr)); + return arr[pos]; } +/* forward */ +static void free_mark(ir_node *node, pset *set); - -/* --- callee analysis ------------------------------------------------------ */ - - -static void callee_ana_node(ir_node * node, eset * methods); - - -static void callee_ana_proj(ir_node * node, long n, eset * methods) { - assert(get_irn_mode(node) == mode_T); - if (get_irn_link(node) == MARK) { - /* already visited */ - return; - } - set_irn_link(node, MARK); - - switch (get_irn_opcode(node)) { - case iro_Proj: { - /* proj_proj: in einem "sinnvollen" Graphen kommt jetzt ein - * op_Tuple oder ein Knoten, der eine "freie Methode" - * zurückgibt. */ - ir_node * pred = get_Proj_pred(node); - if (get_irn_link(pred) != MARK) { - if (get_irn_op(pred) == op_Tuple) { - callee_ana_proj(get_Tuple_pred(pred, get_Proj_proj(node)), n, methods); - } else { - eset_insert(methods, MARK); /* free method -> unknown */ - } - } - break; - } - - case iro_Tuple: - callee_ana_node(get_Tuple_pred(node, n), methods); - break; - - case iro_Id: - callee_ana_proj(get_Id_pred(node), n, methods); - break; - - default: - eset_insert(methods, MARK); /* free method -> unknown */ - break; - } - - set_irn_link(node, NULL); +static void free_mark_proj(ir_node *node, long n, pset *set) +{ + assert(get_irn_mode(node) == mode_T); + if (get_irn_link(node) == MARK) { + /* already visited */ + return; + } + set_irn_link(node, MARK); + switch (get_irn_opcode(node)) { + case iro_Proj: { + /* proj_proj: in einem "sinnvollen" Graphen kommt jetzt ein + * op_Tuple oder ein Knoten, der in "free_ana_walker" behandelt + * wird. */ + ir_node * pred = get_Proj_pred(node); + if (get_irn_link(pred) != MARK && is_Tuple(pred)) { + free_mark_proj(get_Tuple_pred(pred, get_Proj_proj(node)), n, set); + } else { + /* nothing: da in "free_ana_walker" behandelt. */ + } + break; + } + + case iro_Tuple: + free_mark(get_Tuple_pred(node, n), set); + break; + + case iro_Id: + free_mark_proj(get_Id_pred(node), n, set); + break; + + case iro_Start: + case iro_Alloc: + case iro_Load: + /* nothing: Die Operationen werden in free_ana_walker() selbst + * behandelt. */ + break; + + default: + assert(0 && "unexpected opcode or opcode not implemented"); + break; + } + // set_irn_link(node, NULL); } - -static void callee_ana_node(ir_node * node, eset * methods) { - int i; - - assert(mode_is_reference(get_irn_mode(node)) || is_Bad(node)); - /* rekursion verhindern */ - if (get_irn_link(node) == MARK) { - /* already visited */ - return; - } - set_irn_link(node, MARK); - - switch (get_irn_opcode(node)) { - case iro_SymConst: - if (get_SymConst_kind(node) == symconst_addr_ent) { - entity * ent = get_SymConst_entity(node); - assert(ent && is_method_type(get_entity_type(ent))); - eset_insert(methods, ent); - } else { - assert(get_SymConst_kind(node) == symconst_addr_name); - /* externe Methode (wegen fix_symconst!) */ - eset_insert(methods, MARK); /* free method -> unknown */ - } - break; - case iro_Sel: - /* polymorphe Methode */ - for (i = get_Sel_n_methods(node) - 1; i >= 0; --i) { - entity * ent = get_Sel_method(node, i); - if (ent) { - eset_insert(methods, ent); - } else { - eset_insert(methods, MARK); - } - } - break; - - case iro_Bad: - /* nothing */ - break; - - case iro_Phi: /* Vereinigung */ - for (i = get_Phi_n_preds(node) - 1; i >= 0; --i) { - callee_ana_node(get_Phi_pred(node, i), methods); - } - break; - - case iro_Id: - callee_ana_node(get_Id_pred(node), methods); - break; - - case iro_Proj: - callee_ana_proj(get_Proj_pred(node), get_Proj_proj(node), methods); - break; - - case iro_Add: - case iro_Sub: - case iro_Conv: - /* extern */ - eset_insert(methods, MARK); /* free method -> unknown */ - break; - - default: - assert(0 && "invalid opcode or opcode not implemented"); - break; - } - - set_irn_link(node, NULL); +/** + * Called for predecessors nodes of "interesting" ones. + * Interesting ones include all nodes that can somehow make + * a method visible. + * + * If a method (or a set of methods in case of polymorph calls) gets visible, + * add it to the set of 'free' methods + * + * @param node the current visited node + * @param set the set of all free methods + */ +static void free_mark(ir_node *node, pset *set) +{ + if (get_irn_link(node) == MARK) + return; /* already visited */ + + set_irn_link(node, MARK); + + switch (get_irn_opcode(node)) { + case iro_Sel: { + ir_entity *ent = get_Sel_entity(node); + if (is_method_entity(ent)) { + size_t i, n; + for (i = 0, n = get_Sel_n_methods(node); i < n; ++i) { + pset_insert_ptr(set, get_Sel_method(node, i)); + } + } + break; + } + case iro_SymConst: + if (get_SymConst_kind(node) == symconst_addr_ent) { + ir_entity *ent = get_SymConst_entity(node); + if (is_method_entity(ent)) { + pset_insert_ptr(set, ent); + } + } + break; + + case iro_Phi: + { + int i, n; + for (i = 0, n = get_Phi_n_preds(node); i < n; ++i) { + free_mark(get_Phi_pred(node, i), set); + } + break; + } + case iro_Proj: + free_mark_proj(get_Proj_pred(node), get_Proj_proj(node), set); + break; + default: + /* nothing: */ + break; + } } - -static void callee_walker(ir_node * call, void * env) { - if (get_irn_op(call) == op_Call) { - eset * methods = eset_create(); - entity * ent; - entity ** arr = NEW_ARR_F(entity *, 0); - assert(get_irn_op(get_Call_ptr(call)) != op_Id); - callee_ana_node(get_Call_ptr(call), methods); - if (eset_contains(methods, MARK)) { /* unknown method */ - ARR_APP1(entity *, arr, unknown_entity); - } - for (ent = eset_first(methods); ent; ent = eset_next(methods)) { - if (ent != MARK) { - ARR_APP1(entity *, arr, ent); - } - } -#if 0 /* This generates Bad nodes when we don't want it. - Call it with a check for valid cgana information in local_optimize. */ - if (ARR_LEN(arr) == 0 && get_opt_optimize() && get_opt_dyn_meth_dispatch()) { - /* Kann vorkommen, wenn der Vorgänger beispielsweise eine - * Sel-Operation war, die keine Methoden zurückgeben - * konnte. Wir ersetzen die Call-Operation ebenfalls durch - * eine Bad-Operation. Die Verlinkung muss wiederhergestellt - * werden! */ - ir_node *mem = get_Call_mem(call); - turn_into_tuple (call, 5 /* pn_Call_max */); - set_Tuple_pred(call, pn_Call_M_regular , mem); - set_Tuple_pred(call, pn_Call_T_result , new_Bad()); - set_Tuple_pred(call, pn_Call_P_value_res_base, new_Bad()); - set_Tuple_pred(call, pn_Call_X_except , new_Bad()); /* new_Jmp() ?? new_Raise() ?? */ - set_Tuple_pred(call, pn_Call_M_except , new_Bad()); - - } else -#endif - { - /* remove, what we repaired. */ - int i; - for (i = 0; i < ARR_LEN(arr); ++i) { - assert(arr[i]); - //if (arr[i] == unknown_entity) arr[i] = NULL; - } - - set_Call_callee_arr(call, ARR_LEN(arr), arr); - } - DEL_ARR_F(arr); - eset_destroy(methods); - } +/** + * post-walker. Find method addresses. + */ +static void free_ana_walker(ir_node *node, void *env) +{ + pset *set = (pset*) env; + + if (get_irn_link(node) == MARK) { + /* already visited */ + return; + } + switch (get_irn_opcode(node)) { + /* special nodes */ + case iro_Sel: + case iro_SymConst: + case iro_Const: + case iro_Phi: + case iro_Id: + case iro_Proj: + case iro_Tuple: + /* nothing */ + break; + case iro_Call: + { + size_t i, n; + /* we must handle Call nodes specially, because their call address input + do not expose a method address. */ + set_irn_link(node, MARK); + for (i = 0, n = get_Call_n_params(node); i < n; ++i) { + ir_node *pred = get_Call_param(node, i); + if (mode_is_reference(get_irn_mode(pred))) { + free_mark(pred, set); + } + } + break; + } + default: { + int i; + /* other nodes: Alle anderen Knoten nehmen wir als Verr�ter an, bis + * jemand das Gegenteil implementiert. */ + set_irn_link(node, MARK); + for (i = get_irn_arity(node) - 1; i >= 0; --i) { + ir_node *pred = get_irn_n(node, i); + if (mode_is_reference(get_irn_mode(pred))) { + free_mark(pred, set); + } + } + break; + } + } } - -static void remove_Tuples(ir_node * proj, void * env) { - ir_node *new; - if (get_irn_opcode(proj) != iro_Proj) return; - - new = skip_Tuple(proj); - if (new != proj) exchange(proj, new); +/** + * Add all method addresses in global new style initializers to the set. + * + * @note + * We do NOT check the type here, just if it's an entity address. + * The reason for this is code like: + * + * void *p = function; + * + * which is sometimes used to anchor functions. + */ +static void add_method_address_inititializer(ir_initializer_t *initializer, + pset *set) +{ + ir_node *n; + size_t i; + + switch (initializer->kind) { + case IR_INITIALIZER_CONST: + n = initializer->consti.value; + + /* let's check if it's the address of a function */ + if (is_SymConst_addr_ent(n)) { + ir_entity *ent = get_SymConst_entity(n); + + if (is_Method_type(get_entity_type(ent))) + pset_insert_ptr(set, ent); + } + return; + case IR_INITIALIZER_TARVAL: + case IR_INITIALIZER_NULL: + return; + case IR_INITIALIZER_COMPOUND: + for (i = 0; i < initializer->compound.n_initializers; ++i) { + ir_initializer_t *sub_initializer + = initializer->compound.initializers[i]; + add_method_address_inititializer(sub_initializer, set); + } + return; + } + panic("invalid initializer found"); } +/** + * Add all method addresses in global initializers to the set. + * + * @note + * We do NOT check the type here, just if it's an entity address. + * The reason for this is code like: + * + * void *p = function; + * + * which is sometimes used to anchor functions. + */ +static void add_method_address(ir_entity *ent, pset *set) +{ + ir_type *tp; + + /* ignore methods: these of course reference their addresses + * TODO: remove this later once this incorrect self-initialisation is gone + */ + tp = get_entity_type(ent); + if (is_Method_type(tp)) + return; + + if (ent->initializer != NULL) { + add_method_address_inititializer(get_entity_initializer(ent), set); + } +} -/* Bestimmt für jede Call-Operation die Menge der aufrufbaren Methode - * und speichert das Ergebnis in der Call-Operation. (siehe - * "set_Call_callee"). "sel_methods" wird für den Aufbau benötigt und - * muss bereits aufgebaut sein. */ -static void callee_ana(void) { - int i; - /* Alle Graphen analysieren. */ - for (i = get_irp_n_irgs() - 1; i >= 0; --i) { - irg_walk_graph(get_irp_irg(i), callee_walker, remove_Tuples, NULL); - set_irg_callee_info_state(get_irp_irg(i), irg_callee_info_consistent); - } - set_irp_callee_info_state(irg_callee_info_consistent); +/** + * returns a list of 'free' methods, i.e., the methods that can be called + * from external or via function pointers. + * + * Die Datenstrukturen für sel-Methoden (sel_methods) muß vor dem + * Aufruf von "get_free_methods" aufgebaut sein. Die (internen) + * SymConst(name)-Operationen müssen in passende SymConst(ent)-Operationen + * umgewandelt worden sein, d.h. SymConst-Operationen verweisen immer + * auf eine echt externe Methode. + */ +static size_t get_free_methods(ir_entity ***free_methods) +{ + pset *free_set = pset_new_ptr_default(); + size_t i, n, j, m; + ir_entity **arr; + ir_graph *irg; + ir_type *tp; + size_t length; + + for (i = 0, n = get_irp_n_irgs(); i < n; ++i) { + ir_linkage linkage; + irg = get_irp_irg(i); + ir_entity *const ent = get_irg_entity(irg); + linkage = get_entity_linkage(ent); + + if ((linkage & IR_LINKAGE_HIDDEN_USER) || entity_is_externally_visible(ent)) { + pset_insert_ptr(free_set, ent); + } + + ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK); + /* Find all method entities that gets "visible" through this graphs, + * for instance because their address is stored. */ + irg_walk_graph(irg, firm_clear_link, free_ana_walker, free_set); + ir_free_resources(irg, IR_RESOURCE_IRN_LINK); + } + + /* insert all methods that are used in global variables initializers */ + tp = get_glob_type(); + for (j = 0, m = get_class_n_members(tp); j < m; ++j) { + ir_entity *const ent = get_class_member(tp, j); + add_method_address(ent, free_set); + } + tp = get_tls_type(); + for (j = 0, m = get_compound_n_members(tp); j < m; ++j) { + ir_entity *const ent = get_compound_member(tp, j); + add_method_address(ent, free_set); + } + + /* the main program is even then "free", if it's not external visible. */ + irg = get_irp_main_irg(); + if (irg != NULL) + pset_insert_ptr(free_set, get_irg_entity(irg)); + + /* Finally, transform the set into an array. */ + length = pset_count(free_set); + arr = XMALLOCN(ir_entity*, length); + i = 0; + foreach_pset(free_set, ir_entity, ent) { + arr[i++] = ent; + } + del_pset(free_set); + + *free_methods = arr; + return length; } +/*--------------------------------------------------------------------------*/ +/* Callee analysis. */ +/*--------------------------------------------------------------------------*/ +static void callee_ana_node(ir_node *node, pset *methods); -/* --- free method analysis ------------------------------------------------- */ - - -static void free_mark(ir_node * node, eset * set); - -static void free_mark_proj(ir_node * node, long n, eset * set) { - assert(get_irn_mode(node) == mode_T); - if (get_irn_link(node) == MARK) { - /* already visited */ - return; - } - set_irn_link(node, MARK); - switch (get_irn_opcode(node)) { - case iro_Proj: { - /* proj_proj: in einem "sinnvollen" Graphen kommt jetzt ein - * op_Tuple oder ein Knoten, der in "free_ana_walker" behandelt - * wird. */ - ir_node * pred = get_Proj_pred(node); - if (get_irn_link(pred) != MARK && get_irn_op(pred) == op_Tuple) { - free_mark_proj(get_Tuple_pred(pred, get_Proj_proj(node)), n, set); - } else { - /* nothing: da in "free_ana_walker" behandelt. */ - } - break; - } - - case iro_Tuple: - free_mark(get_Tuple_pred(node, n), set); - break; - - case iro_Id: - free_mark_proj(get_Id_pred(node), n, set); - break; - - case iro_Start: - case iro_Alloc: - case iro_Load: - /* nothing: Die Operationen werden in "free_ana_walker" selbst - * behandelt. */ - break; - - default: - assert(0 && "unexpected opcode or opcode not implemented"); - break; - } - set_irn_link(node, NULL); +static void callee_ana_proj(ir_node *node, long n, pset *methods) +{ + assert(get_irn_mode(node) == mode_T); + if (get_irn_link(node) == MARK) { + /* already visited */ + return; + } + set_irn_link(node, MARK); + + switch (get_irn_opcode(node)) { + case iro_Proj: { + /* proj_proj: in einem "sinnvollen" Graphen kommt jetzt ein + * op_Tuple oder ein Knoten, der eine "freie Methode" + * zur�ckgibt. */ + ir_node *pred = get_Proj_pred(node); + if (get_irn_link(pred) != MARK) { + if (is_Tuple(pred)) { + callee_ana_proj(get_Tuple_pred(pred, get_Proj_proj(node)), n, methods); + } else { + pset_insert_ptr(methods, get_unknown_entity()); /* free method -> unknown */ + } + } + break; + } + + case iro_Tuple: + callee_ana_node(get_Tuple_pred(node, n), methods); + break; + + default: + pset_insert_ptr(methods, get_unknown_entity()); /* free method -> unknown */ + break; + } } +/** + * Analyse a Call address. + * + * @param node the node representing the call address + * @param methods after call contains the set of all possibly called entities + */ +static void callee_ana_node(ir_node *node, pset *methods) +{ + assert(mode_is_reference(get_irn_mode(node)) || is_Bad(node)); + /* Beware of recursion */ + if (get_irn_link(node) == MARK) { + /* already visited */ + return; + } + set_irn_link(node, MARK); + + switch (get_irn_opcode(node)) { + case iro_Const: + /* A direct address call. We tread this as an external + call and ignore it completely. */ + pset_insert_ptr(methods, get_unknown_entity()); /* free method -> unknown */ + break; + + case iro_SymConst: { + ir_entity *ent = get_SymConst_entity(node); + assert(ent && is_method_entity(ent)); + pset_insert_ptr(methods, ent); + break; + } + + case iro_Sel: { + /* polymorphic method */ + size_t i, n; + for (i = 0, n = get_Sel_n_methods(node); i < n; ++i) { + ir_entity *ent = get_Sel_method(node, i); + if (ent != NULL) { + pset_insert_ptr(methods, ent); + } else { + pset_insert_ptr(methods, get_unknown_entity()); + } + } + break; + } + + case iro_Bad: + /* nothing */ + break; + + case iro_Phi: { + int i; + for (i = get_Phi_n_preds(node) - 1; i >= 0; --i) { + callee_ana_node(get_Phi_pred(node, i), methods); + } + break; + } + + case iro_Mux: + callee_ana_node(get_Mux_false(node), methods); + callee_ana_node(get_Mux_true(node), methods); + break; + + case iro_Id: + callee_ana_node(get_Id_pred(node), methods); + break; + + case iro_Proj: + callee_ana_proj(get_Proj_pred(node), get_Proj_proj(node), methods); + break; + + case iro_Add: + case iro_Sub: + case iro_Conv: + /* extern */ + pset_insert_ptr(methods, get_unknown_entity()); /* free method -> unknown */ + break; + + default: + assert(0 && "invalid opcode or opcode not implemented"); + break; + } +} -static void free_mark(ir_node * node, eset * set) { - int i; - - if (get_irn_link(node) == MARK) { - return; /* already visited */ - } - set_irn_link(node, MARK); - switch (get_irn_opcode(node)) { - case iro_Sel: { - entity * ent = get_Sel_entity(node); - if (is_method_type(get_entity_type(ent))) { - for (i = get_Sel_n_methods(node) - 1; i >= 0; --i) { - eset_insert(set, get_Sel_method(node, i)); - } - } - break; - } - case iro_SymConst: - if (get_SymConst_kind(node) == symconst_addr_ent) { - entity * ent = get_SymConst_entity(node); - if (is_method_type(get_entity_type(ent))) { - eset_insert(set, ent); - } - } else { - assert(get_SymConst_kind(node) == symconst_addr_name); - /* nothing: SymConst points to extern method */ - } - break; - - case iro_Phi: - for (i = get_Phi_n_preds(node) - 1; i >= 0; --i) { - free_mark(get_Phi_pred(node, i), set); - } - break; - case iro_Id: - free_mark(get_Id_pred(node), set); - break; - case iro_Proj: - free_mark_proj(get_Proj_pred(node), get_Proj_proj(node), set); - break; - default: - /* nothing: Wird unten behandelt! */ - break; - } - set_irn_link(node, NULL); +/** + * Walker: Analyses every Call node and calculates an array of possible + * callees for that call. + */ +static void callee_walker(ir_node *call, void *env) +{ + (void) env; + if (is_Call(call)) { + pset *methods = pset_new_ptr_default(); + ir_entity **arr; + size_t i; + + callee_ana_node(get_Call_ptr(call), methods); + arr = NEW_ARR_F(ir_entity*, pset_count(methods)); + i = 0; + foreach_pset(methods, ir_entity, ent) { + arr[i] = ent; + /* we want the unknown_entity on the zero position for easy tests later */ + if (is_unknown_entity(ent)) { + arr[i] = arr[0]; + arr[0] = get_unknown_entity(); + } + ++i; + } + set_Call_callee_arr(call, ARR_LEN(arr), arr); + DEL_ARR_F(arr); + del_pset(methods); + } } +/** + * Walker: Removes all tuple. + */ +static void remove_Tuples(ir_node *proj, void *env) +{ + ir_node *nn; + (void) env; + if (! is_Proj(proj)) return; -static void free_ana_walker(ir_node * node, eset * set) { - int i; - if (get_irn_link(node) == MARK) { - /* bereits in einem Zyklus besucht. */ - return; - } - switch (get_irn_opcode(node)) { - /* special nodes */ - case iro_Sel: - case iro_SymConst: - case iro_Const: - case iro_Phi: - case iro_Id: - case iro_Proj: - case iro_Tuple: - /* nothing */ - break; - /* Sonderbehandlung, da der Funktionszeigereingang natürlich kein - * Verräter ist. */ - case iro_Call: - set_irn_link(node, MARK); - for (i = get_Call_arity(node) - 1; i >= 0; --i) { - ir_node * pred = get_Call_param(node, i); - if (mode_is_reference(get_irn_mode(pred))) { - free_mark(pred, set); - } - } - break; - /* other nodes: Alle anderen Knoten nehmen wir als Verräter an, bis - * jemand das Gegenteil implementiert. */ - default: - set_irn_link(node, MARK); - for (i = get_irn_arity(node) - 1; i >= 0; --i) { - ir_node * pred = get_irn_n(node, i); - if (mode_is_reference(get_irn_mode(pred))) { - free_mark(pred, set); - } - } - break; - } - set_irn_link(node, NULL); + nn = skip_Tuple(proj); + if (nn != proj) exchange(proj, nn); } -/* Die Datenstrukturen für sel-Methoden (sel_methods) muß vor dem - * Aufruf von "get_free_methods" aufgebaut sein. Die (internen) - * SymConst-Operationen müssen in passende Const-Operationen - * umgewandelt worden sein, d.h. SymConst-Operationen verweisen immer - * auf eine echt externe Methode. */ -static entity ** get_free_methods(void) +/** + * Determine for every Call the set of possibly called methods and stores it + * inside the Call (@see set_Call_callee()). + * Uses the sel_methods set with much be already calculated. + */ +static void callee_ana(void) { - eset * set = eset_create(); - int i; - entity ** arr = NEW_ARR_F(entity *, 0); - entity * ent; - - for (i = get_irp_n_irgs() - 1; i >= 0; --i) { - ir_graph * irg = get_irp_irg(i); - entity * ent = get_irg_entity(irg); - /* insert "external visible" methods. */ - if (get_entity_visibility(ent) != visibility_local) { - eset_insert(set, ent); - } - /* Finde alle Methoden die in dieser Methode extern sichtbar werden, - z.B. da die Adresse einer Methode abgespeichert wird. */ - irg_walk_graph(irg, NULL, (irg_walk_func *) free_ana_walker, set); - } - - /* insert sticky methods, too */ - for (i = get_irp_n_irgs() - 1; i >= 0; --i) { - ir_graph * irg = get_irp_irg(i); - entity * ent = get_irg_entity(irg); - /* insert "external visible" methods. */ - if (get_entity_stickyness (ent) == stickyness_sticky) { - eset_insert(set, ent); - } - } - - /* Hauptprogramm ist auch dann frei, wenn es nicht "external - * visible" ist. */ - if (get_irp_main_irg()) { - eset_insert(set, get_irg_entity(get_irp_main_irg())); - } - /* Wandle Menge in Feld um. Effizienter. */ - for (ent = eset_first(set); ent; ent = eset_next(set)) { - ARR_APP1(entity *, arr, ent); - } - eset_destroy(set); - - return arr; + size_t i, n; + /* analyse all graphs */ + for (i = 0, n = get_irp_n_irgs(); i < n; ++i) { + ir_graph *irg = get_irp_irg(i); + irg_walk_graph(irg, callee_walker, remove_Tuples, NULL); + set_irg_callee_info_state(irg, irg_callee_info_consistent); + } + set_irp_callee_info_state(irg_callee_info_consistent); } -void cgana(int *length, entity ***free_methods) { - entity ** free_meths, **p; +/*--------------------------------------------------------------------------*/ +/* Cleanup after analyses. */ +/*--------------------------------------------------------------------------*/ - sel_methods_init(); - free_meths = get_free_methods(); - callee_ana(); - sel_methods_dispose(); - - /* Convert the flexible array to an array that can be handled - by standard C. */ - p = xmalloc(sizeof(*p) * ARR_LEN(free_meths)); - memcpy(p, free_meths, ARR_LEN(free_meths) * sizeof(*p)); - - *length = ARR_LEN(free_meths); - *free_methods = p; - - DEL_ARR_F(free_meths); +/** Frees intermediate data structures. */ +static void sel_methods_dispose(void) +{ + assert(entities); + foreach_pset(entities, ir_entity, ent) { + ir_entity **arr = (ir_entity**) get_entity_link(ent); + if (arr != NULL) { + DEL_ARR_F(arr); + } + set_entity_link(ent, NULL); + } + del_pset(entities); + entities = NULL; } +static void destruct_walker(ir_node * node, void * env) +{ + (void) env; + if (is_Call(node)) { + remove_Call_callee_arr(node); + } +} - -static void destruct_walker(ir_node * node, void * env) { - if (get_irn_op(node) == op_Call) { - remove_Call_callee_arr(node); - } +size_t cgana(ir_entity ***free_methods) +{ + size_t length; + /* Optimize Sel/SymConst nodes and compute all methods that implement an entity. */ + sel_methods_init(); + length = get_free_methods(free_methods); + callee_ana(); + sel_methods_dispose(); + return length; } -void free_callee_info(ir_graph *irg) { - irg_walk_graph(irg, destruct_walker, NULL, NULL); - set_irg_callee_info_state(irg, irg_callee_info_none); +void free_callee_info(ir_graph *irg) +{ + irg_walk_graph(irg, destruct_walker, NULL, NULL); + set_irg_callee_info_state(irg, irg_callee_info_none); } +void free_irp_callee_info(void) +{ + size_t i, n; + for (i = 0, n = get_irp_n_irgs(); i < n; ++i) { + free_callee_info(get_irp_irg(i)); + } +} -/* Optimize the address expressions passed to call nodes. - * - * This optimization performs the following transformations for - * all ir graphs: - * - All SymConst operations that refer to intern methods are replaced - * by Const operations refering to the corresponding entity. - * - Sel nodes, that select entities that are not overwritten are - * replaced by Const nodes refering to the selected entity. - * - Sel nodes, for witch no method exists at all are replaced by Bad - * nodes. - * - Sel nodes with a pointer input that is an Alloc node are replaced - * by Const nodes refering to the entity that implements the method in - * the type given by the Alloc node. - */ -void opt_call_addrs(void) { - sel_methods_init(); - sel_methods_dispose(); +void opt_call_addrs(void) +{ + /* Optimize the address expressions passed to call nodes. + * + * This optimization performs the following transformations for + * all ir graphs: + * - All SymConst operations that refer to intern methods are replaced + * by Const operations referring to the corresponding entity. + * - Sel nodes, that select entities that are not overwritten are + * replaced by Const nodes referring to the selected entity. + * - Sel nodes, for which no method exists at all are replaced by Bad + * nodes. + * - Sel nodes with a pointer input that is an Alloc node are replaced + * by Const nodes referring to the entity that implements the method in + * the type given by the Alloc node. + */ + sel_methods_init(); + sel_methods_dispose(); }