X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fopt%2Fcombo.c;h=4d80dcf51619a171da332f3d7ffa8e19cca599c7;hb=605982d0319ef990db956a787fe1e727f8076c3f;hp=1fe140d776da1c0425b0f9a0aa6df1ca5bbcf63d;hpb=090736ef38c9b9406e0fc59d82c21a92715e0ca6;p=libfirm diff --git a/ir/opt/combo.c b/ir/opt/combo.c index 1fe140d77..4d80dcf51 100644 --- a/ir/opt/combo.c +++ b/ir/opt/combo.c @@ -22,299 +22,3049 @@ * @brief Cliff Click's Combined Analysis/Optimization * @author Michael Beck * @version $Id$ + * + * Note further that we use the terminology from Click's work here, which is different + * in some cases from Firm terminology. Especially, Click's type is a + * Firm tarval/entity, nevertheless we call it type here for "maximum compatibility". */ #ifdef HAVE_CONFIG_H # include "config.h" #endif -#include "iroptimize.h" #include + +#include "iroptimize.h" +#include "archop.h" +#include "irflag.h" +#include "ircons.h" #include "list.h" +#include "set.h" +#include "pmap.h" #include "obstack.h" #include "irgraph_t.h" #include "irnode_t.h" +#include "iropt_t.h" #include "irgwalk.h" #include "irop.h" #include "irouts.h" #include "irgmod.h" +#include "iropt_dbg.h" #include "debug.h" +#include "error.h" + +#include "tv_t.h" + +#include "irprintf.h" +#include "irdump.h" + +/* define this to check that all type translations are monotone */ +#undef VERIFY_MONOTONE + +/* define this to check the consistency of partitions */ +#define CHECK_PARTITIONS -typedef struct partition_entry_t partition_entry_t; +typedef struct node_t node_t; typedef struct partition_t partition_t; +typedef struct opcode_key_t opcode_key_t; +typedef struct listmap_entry_t listmap_entry_t; + +/** The type of the compute function. */ +typedef void (*compute_func)(node_t *node); + +/** + * An opcode map key. + */ +struct opcode_key_t { + ir_opcode code; /**< The Firm opcode. */ + ir_mode *mode; /**< The mode of all nodes in the partition. */ + int arity; /**< The arity of this opcode (needed for Phi etc. */ + union { + long proj; /**< For Proj nodes, its proj number */ + ir_entity *ent; /**< For Sel Nodes, its entity */ + } u; +}; + +/** + * An entry in the list_map. + */ +struct listmap_entry_t { + void *id; /**< The id. */ + node_t *list; /**< The associated list for this id. */ + listmap_entry_t *next; /**< Link to the next entry in the map. */ +}; + +/** We must map id's to lists. */ +typedef struct listmap_t { + set *map; /**< Map id's to listmap_entry_t's */ + listmap_entry_t *values; /**< List of all values in the map. */ +} listmap_t; + +/** + * A lattice element. Because we handle constants and symbolic constants different, we + * have to use this union. + */ +typedef union { + tarval *tv; + symconst_symbol sym; +} lattice_elem_t; /** - * A partition entry. + * A node. */ -struct partition_entry_t { - ir_node *node; /**< The node itself. */ - list_head list; /**< double-linked list */ - partition_t *part; /**< points to the partition this entry belongs to */ - partition_entry_t *touched_next; /**< Next entry on partition.touched set. */ - unsigned on_touched:1; /**< Set, if this entry is on the partition.touched set. */ +struct node_t { + ir_node *node; /**< The IR-node itself. */ + list_head node_list; /**< Double-linked list of leader/follower entries. */ + list_head cprop_list; /**< Double-linked partition.cprop list. */ + partition_t *part; /**< points to the partition this node belongs to */ + node_t *next; /**< Next node on local list (partition.touched, fallen). */ + node_t *race_next; /**< Next node on race list. */ + lattice_elem_t type; /**< The associated lattice element "type". */ + int max_user_input; /**< Maximum input number of Def-Use edges. */ + int next_edge; /**< Index of the next Def-Use edge to use. */ + int n_followers; /**< Number of Follower in the outs set. */ + unsigned on_touched:1; /**< Set, if this node is on the partition.touched set. */ + unsigned on_cprop:1; /**< Set, if this node is on the partition.cprop list. */ + unsigned on_fallen:1; /**< Set, if this node is on the fallen list. */ + unsigned is_follower:1; /**< Set, if this node is a follower. */ + unsigned by_all_const:1; /**< Set, if this node was once evaluated by all constants. */ + unsigned flagged:2; /**< 2 Bits, set if this node was visited by race 1 or 2. */ }; /** * A partition containing congruent nodes. */ struct partition_t { - list_head entries; /**< The partition entries. */ - partition_t *wl_next; /**< Next entry in the work list if any. */ - partition_t *touched_next; /**< points to the next partition in the touched set. */ - partition_entry_t *touched; /**< the partition.touched set of this partition. */ - unsigned n_entries; /**< number of entries in this partition. */ - unsigned n_touched; /**< number of entries in the partition.touched. */ - int n_inputs; /**< Maximum number of inputs of all entries. */ - unsigned on_worklist:1; /**< Set, if this partition is in the work list. */ - unsigned on_touched:1; /**< Set, if this partition is on the touched set. */ + list_head Leader; /**< The head of partition Leader node list. */ + list_head Follower; /**< The head of partition Follower node list. */ + list_head cprop; /**< The head of partition.cprop list. */ + partition_t *wl_next; /**< Next entry in the work list if any. */ + partition_t *touched_next; /**< Points to the next partition in the touched set. */ + partition_t *cprop_next; /**< Points to the next partition in the cprop list. */ + partition_t *split_next; /**< Points to the next partition in the list that must be split by split_by(). */ + node_t *touched; /**< The partition.touched set of this partition. */ + unsigned n_leader; /**< Number of entries in this partition.Leader. */ + unsigned n_touched; /**< Number of entries in the partition.touched. */ + int max_user_inputs; /**< Maximum number of user inputs of all entries. */ + unsigned on_worklist:1; /**< Set, if this partition is in the work list. */ + unsigned on_touched:1; /**< Set, if this partition is on the touched set. */ + unsigned on_cprop:1; /**< Set, if this partition is on the cprop list. */ + unsigned type_is_T_or_C:1;/**< Set, if all nodes in this partition have type Top or Constant. */ +#ifdef DEBUG_libfirm + partition_t *dbg_next; /**< Link all partitions for debugging */ + unsigned nr; /**< A unique number for (what-)mapping, >0. */ +#endif }; typedef struct environment_t { - struct obstack obst; /**< obstack to allocate data structures. */ - partition_t *worklist; /**< The work list. */ - partition_t *touched; /**< the touched set. */ - partition_t *opcode_map[iro_Last]; /**< The initial partition set. */ + struct obstack obst; /**< obstack to allocate data structures. */ + partition_t *worklist; /**< The work list. */ + partition_t *cprop; /**< The constant propagation list. */ + partition_t *touched; /**< the touched set. */ + partition_t *initial; /**< The initial partition. */ + set *opcode2id_map; /**< The opcodeMode->id map. */ + pmap *type2id_map; /**< The type->id map. */ + int end_idx; /**< -1 for local and 0 for global congruences. */ + int lambda_input; /**< Captured argument for lambda_partition(). */ + char nonstd_cond; /**< Set, if a Condb note has a non-Cmp predecessor. */ + char modified; /**< Set, if the graph was modified. */ +#ifdef DEBUG_libfirm + partition_t *dbg_list; /**< List of all partitions. */ +#endif } environment_t; -#define get_irn_entry(irn) ((partition_entry_t *)get_irn_link(irn)) -#define set_irn_entry(irn, entry) set_irn_link(irn, entry) +/** Type of the what function. */ +typedef void *(*what_func)(const node_t *node, environment_t *env); + +#define get_irn_node(follower) ((node_t *)get_irn_link(follower)) +#define set_irn_node(follower, node) set_irn_link(follower, node) + +/* we do NOT use tarval_unreachable here, instead we use Top for this purpose */ +#undef tarval_unreachable +#define tarval_unreachable tarval_top + /** The debug module handle. */ DEBUG_ONLY(static firm_dbg_module_t *dbg;) +/** Next partition number. */ +DEBUG_ONLY(static unsigned part_nr = 0); + +/** The tarval returned by Unknown nodes. */ +static tarval *tarval_UNKNOWN; + +/* forward */ +static node_t *identity(node_t *node); + +#ifdef CHECK_PARTITIONS +/** + * Check a partition. + */ +static void check_partition(const partition_t *T) { + node_t *node; + unsigned n = 0; + + list_for_each_entry(node_t, node, &T->Leader, node_list) { + assert(node->is_follower == 0); + assert(node->flagged == 0); + assert(node->part == T); + ++n; + } + assert(n == T->n_leader); + + list_for_each_entry(node_t, node, &T->Follower, node_list) { + assert(node->is_follower == 1); + assert(node->flagged == 0); + assert(node->part == T); + } +} /* check_partition */ + +static void check_all_partitions(environment_t *env) { + partition_t *P; + node_t *node; + +#ifdef DEBUG_libfirm + for (P = env->dbg_list; P != NULL; P = P->dbg_next) { + check_partition(P); + list_for_each_entry(node_t, node, &P->Follower, node_list) { + node_t *leader = identity(node); + + assert(leader != node && leader->part == node->part); + } + } +#endif +} + +/** + * Check list. + */ +static void do_check_list(const node_t *list, int ofs, const partition_t *Z) { + const node_t *e; + +#define NEXT(e) *((const node_t **)((char *)(e) + (ofs))) + for (e = list; e != NULL; e = NEXT(e)) { + assert(e->part == Z); + } +#undef NEXT +} /* ido_check_list */ + +/** + * Check a local list. + */ +static void check_list(const node_t *list, const partition_t *Z) { + do_check_list(list, offsetof(node_t, next), Z); +} /* check_list */ + +#else +#define check_partition(T) +#define check_list(list, Z) +#define check_all_partitions(env) +#endif /* CHECK_PARTITIONS */ + #ifdef DEBUG_libfirm -static void dump_partition(partition_t *part) { - partition_entry_t *entry; +static INLINE lattice_elem_t get_partition_type(const partition_t *X); + +/** + * Dump partition to output. + */ +static void dump_partition(const char *msg, const partition_t *part) { + const node_t *node; + int first = 1; + lattice_elem_t type = get_partition_type(part); + + DB((dbg, LEVEL_2, "%s part%u%s (%u, %+F) {\n ", + msg, part->nr, part->type_is_T_or_C ? "*" : "", + part->n_leader, type)); + list_for_each_entry(node_t, node, &part->Leader, node_list) { + DB((dbg, LEVEL_2, "%s%+F", first ? "" : ", ", node->node)); + first = 0; + } + if (! list_empty(&part->Follower)) { + DB((dbg, LEVEL_2, "\n---\n ")); + first = 1; + list_for_each_entry(node_t, node, &part->Follower, node_list) { + DB((dbg, LEVEL_2, "%s%+F", first ? "" : ", ", node->node)); + first = 0; + } + } + DB((dbg, LEVEL_2, "\n}\n")); +} /* dump_partition */ - DB((dbg, LEVEL_2, "{ ")); - list_for_each_entry(partition_entry_t, entry, &part->entries, list) { - DB((dbg, LEVEL_2, "%+F, ", entry->node)); +/** + * Dumps a list. + */ +static void do_dump_list(const char *msg, const node_t *node, int ofs) { + const node_t *p; + int first = 1; + +#define GET_LINK(p, ofs) *((const node_t **)((char *)(p) + (ofs))) + + DB((dbg, LEVEL_3, "%s = {\n ", msg)); + for (p = node; p != NULL; p = GET_LINK(p, ofs)) { + DB((dbg, LEVEL_3, "%s%+F", first ? "" : ", ", p->node)); + first = 0; + } + DB((dbg, LEVEL_3, "\n}\n")); + +#undef GET_LINK +} + +/** + * Dumps a race list. + */ +static void dump_race_list(const char *msg, const node_t *list) { + do_dump_list(msg, list, offsetof(node_t, race_next)); +} + +/** + * Dumps a local list. + */ +static void dump_list(const char *msg, const node_t *list) { + do_dump_list(msg, list, offsetof(node_t, next)); +} + +/** + * Dump all partitions. + */ +static void dump_all_partitions(const environment_t *env) { + const partition_t *P; + + DB((dbg, LEVEL_2, "All partitions\n===============\n")); + for (P = env->dbg_list; P != NULL; P = P->dbg_next) + dump_partition("", P); +} + +#else +#define dump_partition(msg, part) +#define dump_race_list(msg, list) +#define dump_list(msg, list) +#define dump_all_partitions(env) +#endif + +#if defined(VERIFY_MONOTONE) && defined (DEBUG_libfirm) +/** + * Verify that a type transition is monotone + */ +static void verify_type(const lattice_elem_t old_type, const lattice_elem_t new_type) { + if (old_type.tv == new_type.tv) { + /* no change */ + return; + } + if (old_type.tv == tarval_top) { + /* from Top down-to is always allowed */ + return; + } + if (old_type.tv == tarval_reachable) { + panic("verify_type(): wrong translation from %+F to %+F", old_type, new_type); } - DB((dbg, LEVEL_2, "}\n")); + if (new_type.tv == tarval_bottom || new_type.tv == tarval_reachable) { + /* bottom reached */ + return; + } + panic("verify_type(): wrong translation from %+F to %+F", old_type, new_type); } #else -#define dump_partition(part) +#define verify_type(old_type, new_type) #endif +/** + * Compare two pointer values of a listmap. + */ +static int listmap_cmp_ptr(const void *elt, const void *key, size_t size) { + const listmap_entry_t *e1 = elt; + const listmap_entry_t *e2 = key; + + (void) size; + return e1->id != e2->id; +} /* listmap_cmp_ptr */ + +/** + * Initializes a listmap. + * + * @param map the listmap + */ +static void listmap_init(listmap_t *map) { + map->map = new_set(listmap_cmp_ptr, 16); + map->values = NULL; +} /* listmap_init */ + +/** + * Terminates a listmap. + * + * @param map the listmap + */ +static void listmap_term(listmap_t *map) { + del_set(map->map); +} /* listmap_term */ + +/** + * Return the associated listmap entry for a given id. + * + * @param map the listmap + * @param id the id to search for + * + * @return the asociated listmap entry for the given id + */ +static listmap_entry_t *listmap_find(listmap_t *map, void *id) { + listmap_entry_t key, *entry; + + key.id = id; + key.list = NULL; + key.next = NULL; + entry = set_insert(map->map, &key, sizeof(key), HASH_PTR(id)); + + if (entry->list == NULL) { + /* a new entry, put into the list */ + entry->next = map->values; + map->values = entry; + } + return entry; +} /* listmap_find */ + +/** + * Calculate the hash value for an opcode map entry. + * + * @param entry an opcode map entry + * + * @return a hash value for the given opcode map entry + */ +static unsigned opcode_hash(const opcode_key_t *entry) { + return (entry->mode - (ir_mode *)0) * 9 + entry->code + entry->u.proj * 3 + HASH_PTR(entry->u.ent); +} /* opcode_hash */ + +/** + * Compare two entries in the opcode map. + */ +static int cmp_opcode(const void *elt, const void *key, size_t size) { + const opcode_key_t *o1 = elt; + const opcode_key_t *o2 = key; + + (void) size; + return o1->code != o2->code || o1->mode != o2->mode || + o1->arity != o2->arity || + o1->u.proj != o2->u.proj || o1->u.ent != o2->u.ent; +} /* cmp_opcode */ + +/** + * Compare two Def-Use edges for input position. + */ +static int cmp_def_use_edge(const void *a, const void *b) { + const ir_def_use_edge *ea = a; + const ir_def_use_edge *eb = b; + + /* no overrun, because range is [-1, MAXINT] */ + return ea->pos - eb->pos; +} /* cmp_def_use_edge */ + +/** + * We need the Def-Use edges sorted. + */ +static void sort_irn_outs(node_t *node) { + ir_node *irn = node->node; + int n_outs = get_irn_n_outs(irn); + + if (n_outs > 1) { + qsort(&irn->out[1], n_outs, sizeof(irn->out[0]), cmp_def_use_edge); + } + node->max_user_input = irn->out[n_outs].pos; +} /* sort_irn_outs */ + +/** + * Return the type of a node. + * + * @param irn an IR-node + * + * @return the associated type of this node + */ +static INLINE lattice_elem_t get_node_type(const ir_node *irn) { + return get_irn_node(irn)->type; +} /* get_node_type */ + +/** + * Return the tarval of a node. + * + * @param irn an IR-node + * + * @return the associated type of this node + */ +static INLINE tarval *get_node_tarval(const ir_node *irn) { + lattice_elem_t type = get_node_type(irn); + + if (is_tarval(type.tv)) + return type.tv; + return tarval_bottom; +} /* get_node_type */ + +/** + * Add a partition to the worklist. + */ +static INLINE void add_to_worklist(partition_t *X, environment_t *env) { + assert(X->on_worklist == 0); + X->wl_next = env->worklist; + X->on_worklist = 1; + env->worklist = X; +} /* add_to_worklist */ + /** * Create a new empty partition. + * + * @param env the environment + * + * @return a newly allocated partition */ static INLINE partition_t *new_partition(environment_t *env) { partition_t *part = obstack_alloc(&env->obst, sizeof(*part)); - INIT_LIST_HEAD(&part->entries); - part->wl_next = env->worklist; - part->touched_next = NULL; - part->touched = NULL; - part->n_entries = 0; - part->n_touched = 0; - part->n_inputs = 0; - part->on_worklist = 0; - part->on_touched = 0; + INIT_LIST_HEAD(&part->Leader); + INIT_LIST_HEAD(&part->Follower); + INIT_LIST_HEAD(&part->cprop); + part->wl_next = NULL; + part->touched_next = NULL; + part->cprop_next = NULL; + part->split_next = NULL; + part->touched = NULL; + part->n_leader = 0; + part->n_touched = 0; + part->max_user_inputs = 0; + part->on_worklist = 0; + part->on_touched = 0; + part->on_cprop = 0; + part->type_is_T_or_C = 0; +#ifdef DEBUG_libfirm + part->dbg_next = env->dbg_list; + env->dbg_list = part; + part->nr = part_nr++; +#endif return part; -} +} /* new_partition */ + +/** + * Get the first node from a partition. + */ +static INLINE node_t *get_first_node(const partition_t *X) { + return list_entry(X->Leader.next, node_t, node_list); +} /* get_first_node */ + +/** + * Return the type of a partition (assuming partition is non-empty and + * all elements have the same type). + * + * @param X a partition + * + * @return the type of the first element of the partition + */ +static INLINE lattice_elem_t get_partition_type(const partition_t *X) { + const node_t *first = get_first_node(X); + return first->type; +} /* get_partition_type */ /** - * Get the partition for a given opcode. + * Creates a partition node for the given IR-node and place it + * into the given partition. + * + * @param irn an IR-node + * @param part a partition to place the node in + * @param env the environment + * + * @return the created node */ -static INLINE partition_t *get_partition(ir_opcode code, environment_t *env) { - partition_t *part = env->opcode_map[code]; +static node_t *create_partition_node(ir_node *irn, partition_t *part, environment_t *env) { + /* create a partition node and place it in the partition */ + node_t *node = obstack_alloc(&env->obst, sizeof(*node)); - if (part == NULL) { - /* create a new partition and place it on the wait queue */ - part = new_partition(env); + INIT_LIST_HEAD(&node->node_list); + INIT_LIST_HEAD(&node->cprop_list); + node->node = irn; + node->part = part; + node->next = NULL; + node->race_next = NULL; + node->type.tv = tarval_top; + node->max_user_input = 0; + node->next_edge = 0; + node->n_followers = 0; + node->on_touched = 0; + node->on_cprop = 0; + node->on_fallen = 0; + node->is_follower = 0; + node->by_all_const = 0; + node->flagged = 0; + set_irn_node(irn, node); - part->on_worklist = 1; - env->worklist = part; - env->opcode_map[code] = part; + list_add_tail(&node->node_list, &part->Leader); + ++part->n_leader; + + return node; +} /* create_partition_node */ + +/** + * Pre-Walker, init all Block-Phi lists. + */ +static void init_block_phis(ir_node *irn, void *env) { + (void) env; + + if (is_Block(irn)) { + set_Block_phis(irn, NULL); } - return part; -} +} /* init_block_phis */ /** - * Walker, creates the initial partitions, one for every opcode and place them - * on the worklist. + * Post-Walker, initialize all Nodes' type to U or top and place + * all nodes into the TOP partition. */ static void create_initial_partitions(ir_node *irn, void *ctx) { environment_t *env = ctx; - ir_opcode code = get_irn_opcode(irn); - partition_t *part = get_partition(code, env); - int arity; - - /* create a partition entry and place it in the partition */ - partition_entry_t *entry = obstack_alloc(&env->obst, sizeof(*entry)); - - INIT_LIST_HEAD(&entry->list); - entry->node = irn; - entry->part = part; - entry->touched_next = NULL; - entry->on_touched = 0; - set_irn_entry(irn, entry); - - list_add_tail(&entry->list, &part->entries); - ++part->n_entries; - - arity = get_irn_arity(irn); - if (arity > part->n_inputs) - part->n_inputs = arity; -} + partition_t *part = env->initial; + node_t *node; + + node = create_partition_node(irn, part, env); + sort_irn_outs(node); + if (node->max_user_input > part->max_user_inputs) + part->max_user_inputs = node->max_user_input; + + if (is_Phi(irn)) { + add_Block_phi(get_nodes_block(irn), irn); + } else if (is_Cond(irn)) { + /* check if all Cond's have a Cmp predecessor. */ + if (get_irn_mode(irn) == mode_b && !is_Cmp(skip_Proj(get_Cond_selector(irn)))) + env->nonstd_cond = 1; -/** - * Add a partition to the touched set if not already there. - */ -static INLINE void add_to_touched(partition_t *part, environment_t *env) { - if (part->on_touched == 0) { - part->touched_next = env->touched; - env->touched = part; - part->on_touched = 1; } -} +} /* create_initial_partitions */ /** - * Add an entry to the entry.partition.touched set if not already there.. + * Add a node to the entry.partition.touched set and + * node->partition to the touched set if not already there. + * + * @param y a node + * @param env the environment */ -static INLINE void add_to_partition_touched(partition_entry_t *y) { +static INLINE void add_to_touched(node_t *y, environment_t *env) { if (y->on_touched == 0) { partition_t *part = y->part; - y->touched_next = part->touched; - part->touched = y; + y->next = part->touched; + part->touched = y; + y->on_touched = 1; ++part->n_touched; - y->on_touched = 1; + + if (part->on_touched == 0) { + part->touched_next = env->touched; + env->touched = part; + part->on_touched = 1; + } + + check_list(part->touched, part); } -} +} /* add_to_touched */ /** - * Split a partition by the touched set. + * Place a node on the cprop list. + * + * @param y the node + * @param env the environment */ -static partition_t *split(partition_t *Z, partition_entry_t *g, environment_t *env) { - partition_t *Z_prime; - partition_entry_t *entry; - unsigned n = 0; +static void add_to_cprop(node_t *y, environment_t *env) { + /* Add y to y.partition.cprop. */ + if (y->on_cprop == 0) { + partition_t *Y = y->part; - /* Remove g from Z. */ - for (entry = g; entry != NULL; entry = entry->touched_next) { - list_del(&entry->list); - entry->on_touched = 0; - ++n; + list_add_tail(&y->cprop_list, &Y->cprop); + y->on_cprop = 1; + + DB((dbg, LEVEL_3, "Add %+F to part%u.cprop\n", y->node, Y->nr)); + + /* place its partition on the cprop list */ + if (Y->on_cprop == 0) { + Y->cprop_next = env->cprop; + env->cprop = Y; + Y->on_cprop = 1; + } } - Z->n_entries -= n; + if (get_irn_mode(y->node) == mode_T) { + /* mode_T nodes always produce tarval_bottom, so we must explicitly + add it's Proj's to get constant evaluation to work */ + int i; - /* Move g to a new partition, Z’. */ - Z_prime = new_partition(env); - for (entry = g; entry != NULL; entry = entry->touched_next) { - list_add(&entry->list, &Z_prime->entries); - entry->part = Z_prime; - } - Z_prime->n_entries = n; - - /* If Z is on worklist then add Z’ to worklist. - Else add the smaller of Z and Z’ to worklist. */ - if (Z->on_worklist || Z_prime->n_entries < Z->n_entries) { - Z_prime->on_worklist = 1; - Z_prime->wl_next = env->worklist; - env->worklist = Z_prime; + for (i = get_irn_n_outs(y->node) - 1; i >= 0; --i) { + node_t *proj = get_irn_node(get_irn_out(y->node, i)); + + add_to_cprop(proj, env); + } + } else if (is_Block(y->node)) { + /* Due to the way we handle Phi's, we must place all Phis of a block on the list + * if someone placed the block. The Block is only placed if the reachability + * changes, and this must be re-evaluated in compute_Phi(). */ + ir_node *phi; + for (phi = get_Block_phis(y->node); phi != NULL; phi = get_Phi_next(phi)) { + node_t *p = get_irn_node(phi); + add_to_cprop(p, env); + } + } +} /* add_to_cprop */ + +/** + * Update the worklist: If Z is on worklist then add Z' to worklist. + * Else add the smaller of Z and Z' to worklist. + * + * @param Z the Z partition + * @param Z_prime the Z' partition, a previous part of Z + * @param env the environment + */ +static void update_worklist(partition_t *Z, partition_t *Z_prime, environment_t *env) { + if (Z->on_worklist || Z_prime->n_leader < Z->n_leader) { + add_to_worklist(Z_prime, env); } else { - Z->on_worklist = 1; - Z->wl_next = env->worklist; - env->worklist = Z; + add_to_worklist(Z, env); } - return Z_prime; -} +} /* update_worklist */ /** - * Split the partitions if caused by the first entry on the worklist. + * Make all inputs to x no longer be F.def_use edges. + * + * @param x the node */ -static void cause_splits(environment_t *env) { - partition_t *X, *Z; - partition_entry_t *x, *y, *e; - int i; +static void move_edges_to_leader(node_t *x) { + ir_node *irn = x->node; + int i, j, k; - /* remove the first partition from the worklist */ - X = env->worklist; - env->worklist = X->wl_next; - X->on_worklist = 0; + for (i = get_irn_arity(irn) - 1; i >= 0; --i) { + node_t *pred = get_irn_node(get_irn_n(irn, i)); + ir_node *p; + int n; - for (i = X->n_inputs - 1; i >= -1; --i) { - /* empty the touched set: already done, just clear the list */ - env->touched = NULL; + p = pred->node; + n = get_irn_n_outs(p); + for (j = 1; j <= pred->n_followers; ++j) { + if (p->out[j].pos == i && p->out[j].use == irn) { + /* found a follower edge to x, move it to the Leader */ + ir_def_use_edge edge = p->out[j]; - list_for_each_entry(partition_entry_t, x, &X->entries, list) { - if (i < get_irn_arity(x->node) && (!is_Block(x->node) || i >= 0)) { - y = get_irn_entry(get_irn_n(x->node, i)); + /* remove this edge from the Follower set */ + p->out[j] = p->out[pred->n_followers]; + --pred->n_followers; - add_to_touched(y->part, env); - add_to_partition_touched(y); + /* sort it into the leader set */ + for (k = pred->n_followers + 2; k <= n; ++k) { + if (p->out[k].pos >= edge.pos) + break; + p->out[k - 1] = p->out[k]; + } + /* place the new edge here */ + p->out[k - 1] = edge; + + /* edge found and moved */ + break; } } + } +} /* move_edges_to_leader */ - for (Z = env->touched; Z != NULL; Z = Z->touched_next) { - /* remove it from the touched set */ - Z->on_touched = 0; +/** + * Split a partition that has NO followers by a local list. + * + * @param Z partition to split + * @param g a (non-empty) node list + * @param env the environment + * + * @return a new partition containing the nodes of g + */ +static partition_t *split_no_followers(partition_t *Z, node_t *g, environment_t *env) { + partition_t *Z_prime; + node_t *node; + unsigned n = 0; + int max_input; - if (Z->n_entries != Z->n_touched) { - split(Z, Z->touched, env); - } - /* Empty Z.touched. */ - for (e = Z->touched; e != NULL; e = e->touched_next) { - e->on_touched = 0; - } - Z->touched = NULL; - } + dump_partition("Splitting ", Z); + dump_list("by list ", g); + assert(g != NULL); + + /* Remove g from Z. */ + for (node = g; node != NULL; node = node->next) { + assert(node->part == Z); + list_del(&node->node_list); + ++n; } -} + assert(n < Z->n_leader); + Z->n_leader -= n; + + /* Move g to a new partition, Z'. */ + Z_prime = new_partition(env); + max_input = 0; + for (node = g; node != NULL; node = node->next) { + list_add_tail(&node->node_list, &Z_prime->Leader); + node->part = Z_prime; + if (node->max_user_input > max_input) + max_input = node->max_user_input; + } + Z_prime->max_user_inputs = max_input; + Z_prime->n_leader = n; + + check_partition(Z); + check_partition(Z_prime); + + /* for now, copy the type info tag, it will be adjusted in split_by(). */ + Z_prime->type_is_T_or_C = Z->type_is_T_or_C; + + update_worklist(Z, Z_prime, env); + + dump_partition("Now ", Z); + dump_partition("Created new ", Z_prime); + return Z_prime; +} /* split_no_followers */ /** - * Get the leader for a given node from its congruence class. + * Make the Follower -> Leader transition for a node. * - * @param irn the node + * @param n the node */ -static ir_node *get_leader(ir_node *irn) { - partition_t *part = get_irn_entry(irn)->part; +static void follower_to_leader(node_t *n) { + assert(n->is_follower == 1); - if (part->n_entries > 1) { - DB((dbg, LEVEL_2, "Found congruence class for %+F ", irn)); - dump_partition(part); - } - return irn; -} + DB((dbg, LEVEL_2, "%+F make the follower -> leader transition\n", n->node)); + n->is_follower = 0; + move_edges_to_leader(n); + list_del(&n->node_list); + list_add_tail(&n->node_list, &n->part->Leader); + ++n->part->n_leader; +} /* follower_to_leader */ /** - * Post-Walker, apply the analysis results; + * The environment for one race step. */ -static void apply_result(ir_node *irn, void *ctx) { - environment_t *env = ctx; +typedef struct step_env { + node_t *initial; /**< The initial node list. */ + node_t *unwalked; /**< The unwalked node list. */ + node_t *walked; /**< The walked node list. */ + int index; /**< Next index of Follower use_def edge. */ + unsigned side; /**< side number. */ +} step_env; + +/** + * Return non-zero, if a input is a real follower + * + * @param irn the node to check + * @param input number of the input + */ +static int is_real_follower(const ir_node *irn, int input) { + node_t *pred; - ir_node *leader = get_leader(irn); + switch (get_irn_opcode(irn)) { + case iro_Confirm: + if (input == 1) { + /* ignore the Confirm bound input */ + return 0; + } + break; + case iro_Mux: + if (input == 0) { + /* ignore the Mux sel input */ + return 0; + } + break; + case iro_Phi: { + /* dead inputs are not follower edges */ + ir_node *block = get_nodes_block(irn); + node_t *pred = get_irn_node(get_Block_cfgpred(block, input)); - if (leader != irn) { - exchange(irn, leader); + if (pred->type.tv == tarval_unreachable) + return 0; + break; + } + case iro_Sub: + case iro_Shr: + case iro_Shl: + case iro_Shrs: + case iro_Rotl: + if (input == 1) { + /* only a Sub x,0 / Shift x,0 might be a follower */ + return 0; + } + break; + case iro_Add: + case iro_Or: + case iro_Eor: + pred = get_irn_node(get_irn_n(irn, input)); + if (is_tarval(pred->type.tv) && tarval_is_null(pred->type.tv)) + return 0; + break; + case iro_Mul: + pred = get_irn_node(get_irn_n(irn, input)); + if (is_tarval(pred->type.tv) && tarval_is_one(pred->type.tv)) + return 0; + break; + case iro_And: + pred = get_irn_node(get_irn_n(irn, input)); + if (is_tarval(pred->type.tv) && tarval_is_all_one(pred->type.tv)) + return 0; + break; + case iro_Min: + case iro_Max: + /* all inputs are followers */ + return 1; + default: + assert(!"opcode not implemented yet"); + break; } + return 1; } -void combo(ir_graph *irg) { - environment_t env; +/** + * Do one step in the race. + */ +static int step(step_env *env) { + node_t *n; - /* register a debug mask */ - FIRM_DBG_REGISTER(dbg, "firm.opt.combo"); - firm_dbg_set_mask(dbg, SET_LEVEL_2); + if (env->initial != NULL) { + /* Move node from initial to unwalked */ + n = env->initial; + env->initial = n->race_next; - obstack_init(&env.obst); - env.worklist = NULL; - env.touched = NULL; - memset(env.opcode_map, 0, sizeof(env.opcode_map)); + n->race_next = env->unwalked; + env->unwalked = n; - assure_irg_outs(irg); + return 0; + } - /* create the initial partitions */ - irg_walk_graph(irg, NULL, create_initial_partitions, &env); + while (env->unwalked != NULL) { + /* let n be the first node in unwalked */ + n = env->unwalked; + while (env->index < n->n_followers) { + const ir_def_use_edge *edge = &n->node->out[1 + env->index]; - while (env.worklist != NULL) - cause_splits(&env); + /* let m be n.F.def_use[index] */ + node_t *m = get_irn_node(edge->use); - /* apply the result */ - irg_walk_graph(irg, NULL, apply_result, &env); + assert(m->is_follower); + /* + * Some inputs, like the get_Confirm_bound are NOT + * real followers, sort them out. + */ + if (! is_real_follower(m->node, edge->pos)) { + ++env->index; + continue; + } + ++env->index; - obstack_free(&env.obst, NULL); + /* only followers from our partition */ + if (m->part != n->part) + continue; + + if ((m->flagged & env->side) == 0) { + m->flagged |= env->side; + + if (m->flagged != 3) { + /* visited the first time */ + /* add m to unwalked not as first node (we might still need to + check for more follower node */ + m->race_next = n->race_next; + n->race_next = m; + return 0; + } + /* else already visited by the other side and on the other list */ + } + } + /* move n to walked */ + env->unwalked = n->race_next; + n->race_next = env->walked; + env->walked = n; + env->index = 0; + } + return 1; +} /* step */ + +/** + * Clear the flags from a list and check for + * nodes that where touched from both sides. + * + * @param list the list + */ +static int clear_flags(node_t *list) { + int res = 0; + node_t *n; + + for (n = list; n != NULL; n = n->race_next) { + if (n->flagged == 3) { + /* we reach a follower from both sides, this will split congruent + * inputs and make it a leader. */ + follower_to_leader(n); + res = 1; + } + n->flagged = 0; + } + return res; +} /* clear_flags */ + +/** + * Split a partition by a local list using the race. + * + * @param pX pointer to the partition to split, might be changed! + * @param gg a (non-empty) node list + * @param env the environment + * + * @return a new partition containing the nodes of gg + */ +static partition_t *split(partition_t **pX, node_t *gg, environment_t *env) { + partition_t *X = *pX; + partition_t *X_prime; + list_head tmp; + step_env env1, env2, *winner; + node_t *g, *h, *node, *t; + int max_input, transitions; + unsigned n; + DEBUG_ONLY(static int run = 0;) + + DB((dbg, LEVEL_2, "Run %d ", run++)); + if (list_empty(&X->Follower)) { + /* if the partition has NO follower, we can use the fast + splitting algorithm. */ + return split_no_followers(X, gg, env); + } + /* else do the race */ + + dump_partition("Splitting ", X); + dump_list("by list ", gg); + + INIT_LIST_HEAD(&tmp); + + /* Remove gg from X.Leader and put into g */ + g = NULL; + for (node = gg; node != NULL; node = node->next) { + assert(node->part == X); + assert(node->is_follower == 0); + + list_del(&node->node_list); + list_add_tail(&node->node_list, &tmp); + node->race_next = g; + g = node; + } + /* produce h */ + h = NULL; + list_for_each_entry(node_t, node, &X->Leader, node_list) { + node->race_next = h; + h = node; + } + /* restore X.Leader */ + list_splice(&tmp, &X->Leader); + + env1.initial = g; + env1.unwalked = NULL; + env1.walked = NULL; + env1.index = 0; + env1.side = 1; + + env2.initial = h; + env2.unwalked = NULL; + env2.walked = NULL; + env2.index = 0; + env2.side = 2; + + for (;;) { + if (step(&env1)) { + winner = &env1; + break; + } + if (step(&env2)) { + winner = &env2; + break; + } + } + assert(winner->initial == NULL); + assert(winner->unwalked == NULL); + + /* clear flags from walked/unwalked */ + transitions = clear_flags(env1.unwalked); + transitions |= clear_flags(env1.walked); + transitions |= clear_flags(env2.unwalked); + transitions |= clear_flags(env2.walked); + + dump_race_list("winner ", winner->walked); + + /* Move walked_{winner} to a new partition, X'. */ + X_prime = new_partition(env); + max_input = 0; + n = 0; + for (node = winner->walked; node != NULL; node = node->race_next) { + list_del(&node->node_list); + node->part = X_prime; + if (node->is_follower) { + list_add_tail(&node->node_list, &X_prime->Follower); + } else { + list_add_tail(&node->node_list, &X_prime->Leader); + ++n; + } + if (node->max_user_input > max_input) + max_input = node->max_user_input; + } + X_prime->n_leader = n; + X_prime->max_user_inputs = max_input; + X->n_leader -= X_prime->n_leader; + + /* for now, copy the type info tag, it will be adjusted in split_by(). */ + X_prime->type_is_T_or_C = X->type_is_T_or_C; + + /* + * Even if a follower was not checked by both sides, it might have + * loose its congruence, so we need to check this case for all follower. + */ + list_for_each_entry_safe(node_t, node, t, &X_prime->Follower, node_list) { + if (identity(node) == node) { + follower_to_leader(node); + transitions = 1; + } + } + + check_partition(X); + check_partition(X_prime); + + /* X' is the smaller part */ + add_to_worklist(X_prime, env); + + /* + * If there where follower to leader transitions, ensure that the nodes + * can be split out if necessary. + */ + if (transitions) { + /* place partitions on the cprop list */ + if (X_prime->on_cprop == 0) { + X_prime->cprop_next = env->cprop; + env->cprop = X_prime; + X_prime->on_cprop = 1; + } + } + + dump_partition("Now ", X); + dump_partition("Created new ", X_prime); + + /* we have to ensure that the partition containing g is returned */ + if (winner == &env2) { + *pX = X_prime; + return X; + } + + return X_prime; +} /* split */ + +/** + * Returns non-zero if the i'th input of a Phi node is live. + * + * @param phi a Phi-node + * @param i an input number + * + * @return non-zero if the i'th input of the given Phi node is live + */ +static int is_live_input(ir_node *phi, int i) { + if (i >= 0) { + ir_node *block = get_nodes_block(phi); + ir_node *pred = get_Block_cfgpred(block, i); + lattice_elem_t type = get_node_type(pred); + + return type.tv != tarval_unreachable; + } + /* else it's the control input, always live */ + return 1; +} /* is_live_input */ + +/** + * Return non-zero if a type is a constant. + */ +static int is_constant_type(lattice_elem_t type) { + if (type.tv != tarval_bottom && type.tv != tarval_top) + return 1; + return 0; +} /* is_constant_type */ + +/** + * Check whether a type is neither Top or a constant. + * Note: U is handled like Top here, R is a constant. + * + * @param type the type to check + */ +static int type_is_neither_top_nor_const(const lattice_elem_t type) { + if (is_tarval(type.tv)) { + if (type.tv == tarval_top) + return 0; + if (tarval_is_constant(type.tv)) + return 0; + } else { + /* is a symconst */ + return 0; + } + return 1; +} + +/** + * Collect nodes to the touched list. + * + * @param list the list which contains the nodes that must be evaluated + * @param idx the index of the def_use edge to evaluate + * @param env the environment + */ +static void collect_touched(list_head *list, int idx, environment_t *env) { + node_t *x, *y; + int end_idx = env->end_idx; + + list_for_each_entry(node_t, x, list, node_list) { + int num_edges; + + if (idx == -1) { + /* leader edges start AFTER follower edges */ + x->next_edge = x->n_followers + 1; + } + num_edges = get_irn_n_outs(x->node); + + /* for all edges in x.L.def_use_{idx} */ + while (x->next_edge <= num_edges) { + const ir_def_use_edge *edge = &x->node->out[x->next_edge]; + ir_node *succ; + + /* check if we have necessary edges */ + if (edge->pos > idx) + break; + + ++x->next_edge; + + succ = edge->use; + + /* ignore the "control input" for non-pinned nodes + if we are running in GCSE mode */ + if (idx < end_idx && get_irn_pinned(succ) != op_pin_state_pinned) + continue; + + y = get_irn_node(succ); + assert(get_irn_n(succ, idx) == x->node); + + /* ignore block edges touching followers */ + if (idx == -1 && y->is_follower) + continue; + + if (is_constant_type(y->type)) { + ir_opcode code = get_irn_opcode(succ); + if (code == iro_Sub || code == iro_Eor || code == iro_Cmp) + add_to_cprop(y, env); + } + + /* Partitions of constants should not be split simply because their Nodes have unequal + functions or incongruent inputs. */ + if (type_is_neither_top_nor_const(y->type) && + (! is_Phi(y->node) || is_live_input(y->node, idx))) { + add_to_touched(y, env); + } + } + } +} /* collect_touched */ + +/** + * Split the partitions if caused by the first entry on the worklist. + * + * @param env the environment + */ +static void cause_splits(environment_t *env) { + partition_t *X, *Z, *N; + int idx; + + /* remove the first partition from the worklist */ + X = env->worklist; + env->worklist = X->wl_next; + X->on_worklist = 0; + + dump_partition("Cause_split: ", X); + + /* combine temporary leader and follower list */ + for (idx = -1; idx <= X->max_user_inputs; ++idx) { + /* empty the touched set: already done, just clear the list */ + env->touched = NULL; + + collect_touched(&X->Leader, idx, env); + collect_touched(&X->Follower, idx, env); + + for (Z = env->touched; Z != NULL; Z = N) { + node_t *e; + node_t *touched = Z->touched; + unsigned n_touched = Z->n_touched; + + assert(Z->touched != NULL); + + /* beware, split might change Z */ + N = Z->touched_next; + + /* remove it from the touched set */ + Z->on_touched = 0; + + /* Empty local Z.touched. */ + for (e = touched; e != NULL; e = e->next) { + assert(e->is_follower == 0); + e->on_touched = 0; + } + Z->touched = NULL; + Z->n_touched = 0; + + if (0 < n_touched && n_touched < Z->n_leader) { + DB((dbg, LEVEL_2, "Split part%d by touched\n", Z->nr)); + split(&Z, touched, env); + } else + assert(n_touched <= Z->n_leader); + } + } +} /* cause_splits */ + +/** + * Implements split_by_what(): Split a partition by characteristics given + * by the what function. + * + * @param X the partition to split + * @param What a function returning an Id for every node of the partition X + * @param P a list to store the result partitions + * @param env the environment + * + * @return *P + */ +static partition_t *split_by_what(partition_t *X, what_func What, + partition_t **P, environment_t *env) { + node_t *x, *S; + listmap_t map; + listmap_entry_t *iter; + partition_t *R; + + /* Let map be an empty mapping from the range of What to (local) list of Nodes. */ + listmap_init(&map); + list_for_each_entry(node_t, x, &X->Leader, node_list) { + void *id = What(x, env); + listmap_entry_t *entry; + + if (id == NULL) { + /* input not allowed, ignore */ + continue; + } + /* Add x to map[What(x)]. */ + entry = listmap_find(&map, id); + x->next = entry->list; + entry->list = x; + } + /* Let P be a set of Partitions. */ + + /* for all sets S except one in the range of map do */ + for (iter = map.values; iter != NULL; iter = iter->next) { + if (iter->next == NULL) { + /* this is the last entry, ignore */ + break; + } + S = iter->list; + + /* Add SPLIT( X, S ) to P. */ + DB((dbg, LEVEL_2, "Split part%d by what\n", X->nr)); + R = split(&X, S, env); + R->split_next = *P; + *P = R; + } + /* Add X to P. */ + X->split_next = *P; + *P = X; + + listmap_term(&map); + return *P; +} /* split_by_what */ + +/** lambda n.(n.type) */ +static void *lambda_type(const node_t *node, environment_t *env) { + (void)env; + return node->type.tv; +} /* lambda_type */ + +/** lambda n.(n.opcode) */ +static void *lambda_opcode(const node_t *node, environment_t *env) { + opcode_key_t key, *entry; + ir_node *irn = node->node; + + key.code = get_irn_opcode(irn); + key.mode = get_irn_mode(irn); + key.arity = get_irn_arity(irn); + key.u.proj = 0; + key.u.ent = NULL; + + switch (get_irn_opcode(irn)) { + case iro_Proj: + key.u.proj = get_Proj_proj(irn); + break; + case iro_Sel: + key.u.ent = get_Sel_entity(irn); + break; + default: + break; + } + + entry = set_insert(env->opcode2id_map, &key, sizeof(key), opcode_hash(&key)); + return entry; +} /* lambda_opcode */ + +/** lambda n.(n[i].partition) */ +static void *lambda_partition(const node_t *node, environment_t *env) { + ir_node *skipped = skip_Proj(node->node); + ir_node *pred; + node_t *p; + int i = env->lambda_input; + + if (i >= get_irn_arity(node->node)) { + /* we are outside the allowed range */ + return NULL; + } + + /* ignore the "control input" for non-pinned nodes + if we are running in GCSE mode */ + if (i < env->end_idx && get_irn_pinned(skipped) != op_pin_state_pinned) + return NULL; + + pred = i == -1 ? get_irn_n(skipped, i) : get_irn_n(node->node, i); + p = get_irn_node(pred); + + return p->part; +} /* lambda_partition */ + +/** + * Returns true if a type is a constant. + */ +static int is_con(const lattice_elem_t type) { + /* be conservative */ + if (is_tarval(type.tv)) + return tarval_is_constant(type.tv); + return is_entity(type.sym.entity_p); +} /* is_con */ + +/** + * Implements split_by(). + * + * @param X the partition to split + * @param env the environment + */ +static void split_by(partition_t *X, environment_t *env) { + partition_t *I, *P = NULL; + int input; + + dump_partition("split_by", X); + + if (X->n_leader == 1) { + /* we have only one leader, no need to split, just check it's type */ + node_t *x = get_first_node(X); + X->type_is_T_or_C = x->type.tv == tarval_top || is_con(x->type); + return; + } + + DB((dbg, LEVEL_2, "WHAT = lambda n.(n.type) on part%d\n", X->nr)); + P = split_by_what(X, lambda_type, &P, env); + + /* adjust the type tags, we have split partitions by type */ + for (I = P; I != NULL; I = I->split_next) { + node_t *x = get_first_node(I); + I->type_is_T_or_C = x->type.tv == tarval_top || is_con(x->type); + } + + do { + partition_t *Y = P; + + P = P->split_next; + if (Y->n_leader > 1) { + /* we do not want split the TOP or constant partitions */ + if (! Y->type_is_T_or_C) { + partition_t *Q = NULL; + + DB((dbg, LEVEL_2, "WHAT = lambda n.(n.opcode) on part%d\n", Y->nr)); + Q = split_by_what(Y, lambda_opcode, &Q, env); + + do { + partition_t *Z = Q; + + Q = Q->split_next; + if (Z->n_leader > 1) { + const node_t *first = get_first_node(Z); + int arity = get_irn_arity(first->node); + partition_t *R, *S; + + /* + * BEWARE: during splitting by input 2 for instance we might + * create new partitions which are different by input 1, so collect + * them and split further. + */ + Z->split_next = NULL; + R = Z; + S = NULL; + for (input = arity - 1; input >= -1; --input) { + do { + partition_t *Z_prime = R; + + R = R->split_next; + if (Z_prime->n_leader > 1) { + env->lambda_input = input; + DB((dbg, LEVEL_2, "WHAT = lambda n.(n[%d].partition) on part%d\n", input, Z_prime->nr)); + S = split_by_what(Z_prime, lambda_partition, &S, env); + } else { + Z_prime->split_next = S; + S = Z_prime; + } + } while (R != NULL); + R = S; + S = NULL; + } + } + } while (Q != NULL); + } + } + } while (P != NULL); +} /* split_by */ + +/** + * (Re-)compute the type for a given node. + * + * @param node the node + */ +static void default_compute(node_t *node) { + int i; + ir_node *irn = node->node; + node_t *block = get_irn_node(get_nodes_block(irn)); + + if (block->type.tv == tarval_unreachable) { + node->type.tv = tarval_top; + return; + } + + /* if any of the data inputs have type top, the result is type top */ + for (i = get_irn_arity(irn) - 1; i >= 0; --i) { + ir_node *pred = get_irn_n(irn, i); + node_t *p = get_irn_node(pred); + + if (p->type.tv == tarval_top) { + node->type.tv = tarval_top; + return; + } + } + + if (get_irn_mode(node->node) == mode_X) + node->type.tv = tarval_reachable; + else + node->type.tv = computed_value(irn); +} /* default_compute */ + +/** + * (Re-)compute the type for a Block node. + * + * @param node the node + */ +static void compute_Block(node_t *node) { + int i; + ir_node *block = node->node; + + if (block == get_irg_start_block(current_ir_graph)) { + /* start block is always reachable */ + node->type.tv = tarval_reachable; + return; + } + + for (i = get_Block_n_cfgpreds(block) - 1; i >= 0; --i) { + node_t *pred = get_irn_node(get_Block_cfgpred(block, i)); + + if (pred->type.tv == tarval_reachable) { + /* A block is reachable, if at least of predecessor is reachable. */ + node->type.tv = tarval_reachable; + return; + } + } + node->type.tv = tarval_top; +} /* compute_Block */ + +/** + * (Re-)compute the type for a Bad node. + * + * @param node the node + */ +static void compute_Bad(node_t *node) { + /* Bad nodes ALWAYS compute Top */ + node->type.tv = tarval_top; +} /* compute_Bad */ + +/** + * (Re-)compute the type for an Unknown node. + * + * @param node the node + */ +static void compute_Unknown(node_t *node) { + /* While Unknown nodes should compute Top this is dangerous: + * a Top input to a Cond would lead to BOTH control flows unreachable. + * While this is correct in the given semantics, it would destroy the Firm + * graph. + * + * It would be safe to compute Top IF it can be assured, that only Cmp + * nodes are inputs to Conds. We check that first. + * This is the way Frontends typically build Firm, but some optimizations + * (cond_eval for instance) might replace them by Phib's... + */ + node->type.tv = tarval_UNKNOWN; +} /* compute_Unknown */ + +/** + * (Re-)compute the type for a Jmp node. + * + * @param node the node + */ +static void compute_Jmp(node_t *node) { + node_t *block = get_irn_node(get_nodes_block(node->node)); + + node->type = block->type; +} /* compute_Jmp */ + +/** + * (Re-)compute the type for the End node. + * + * @param node the node + */ +static void compute_End(node_t *node) { + /* the End node is NOT dead of course */ + node->type.tv = tarval_reachable; +} + +/** + * (Re-)compute the type for a SymConst node. + * + * @param node the node + */ +static void compute_SymConst(node_t *node) { + ir_node *irn = node->node; + node_t *block = get_irn_node(get_nodes_block(irn)); + + if (block->type.tv == tarval_unreachable) { + node->type.tv = tarval_top; + return; + } + switch (get_SymConst_kind(irn)) { + case symconst_addr_ent: + /* case symconst_addr_name: cannot handle this yet */ + node->type.sym = get_SymConst_symbol(irn); + break; + default: + node->type.tv = computed_value(irn); + } +} /* compute_SymConst */ + +/** + * (Re-)compute the type for a Phi node. + * + * @param node the node + */ +static void compute_Phi(node_t *node) { + int i; + ir_node *phi = node->node; + lattice_elem_t type; + + /* if a Phi is in a unreachable block, its type is TOP */ + node_t *block = get_irn_node(get_nodes_block(phi)); + + if (block->type.tv == tarval_unreachable) { + node->type.tv = tarval_top; + return; + } + + /* Phi implements the Meet operation */ + type.tv = tarval_top; + for (i = get_Phi_n_preds(phi) - 1; i >= 0; --i) { + node_t *pred = get_irn_node(get_Phi_pred(phi, i)); + node_t *pred_X = get_irn_node(get_Block_cfgpred(block->node, i)); + + if (pred_X->type.tv == tarval_unreachable || pred->type.tv == tarval_top) { + /* ignore TOP inputs: We must check here for unreachable blocks, + because Firm constants live in the Start Block are NEVER Top. + Else, a Phi (1,2) will produce Bottom, even if the 2 for instance + comes from a unreachable input. */ + continue; + } + if (pred->type.tv == tarval_bottom) { + node->type.tv = tarval_bottom; + return; + } else if (type.tv == tarval_top) { + /* first constant found */ + type = pred->type; + } else if (type.tv != pred->type.tv) { + /* different constants or tarval_bottom */ + node->type.tv = tarval_bottom; + return; + } + /* else nothing, constants are the same */ + } + node->type = type; +} /* compute_Phi */ + +/** + * (Re-)compute the type for an Add. Special case: one nodes is a Zero Const. + * + * @param node the node + */ +static void compute_Add(node_t *node) { + ir_node *sub = node->node; + node_t *l = get_irn_node(get_Add_left(sub)); + node_t *r = get_irn_node(get_Add_right(sub)); + lattice_elem_t a = l->type; + lattice_elem_t b = r->type; + ir_mode *mode; + + if (a.tv == tarval_top || b.tv == tarval_top) { + node->type.tv = tarval_top; + } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) { + node->type.tv = tarval_bottom; + } else { + /* x + 0 = 0 + x = x, but beware of floating point +0 + -0, so we + must call tarval_add() first to handle this case! */ + if (is_tarval(a.tv)) { + if (is_tarval(b.tv)) { + node->type.tv = tarval_add(a.tv, b.tv); + return; + } + mode = get_tarval_mode(a.tv); + if (a.tv == get_mode_null(mode)) { + node->type = b; + return; + } + } else if (is_tarval(b.tv)) { + mode = get_tarval_mode(b.tv); + if (b.tv == get_mode_null(mode)) { + node->type = a; + return; + } + } + node->type.tv = tarval_bottom; + } +} /* compute_Add */ + +/** + * (Re-)compute the type for a Sub. Special case: both nodes are congruent. + * + * @param node the node + */ +static void compute_Sub(node_t *node) { + ir_node *sub = node->node; + node_t *l = get_irn_node(get_Sub_left(sub)); + node_t *r = get_irn_node(get_Sub_right(sub)); + lattice_elem_t a = l->type; + lattice_elem_t b = r->type; + tarval *tv; + + if (a.tv == tarval_top || b.tv == tarval_top) { + node->type.tv = tarval_top; + } else if (is_con(a) && is_con(b)) { + if (is_tarval(a.tv) && is_tarval(b.tv)) { + node->type.tv = tarval_sub(a.tv, b.tv, get_irn_mode(sub)); + } else if (is_tarval(a.tv) && tarval_is_null(a.tv)) { + node->type = b; + } else if (is_tarval(b.tv) && tarval_is_null(b.tv)) { + node->type = a; + } else { + node->type.tv = tarval_bottom; + } + node->by_all_const = 1; + } else if (r->part == l->part && + (!mode_is_float(get_irn_mode(l->node)))) { + /* + * BEWARE: a - a is NOT always 0 for floating Point values, as + * NaN op NaN = NaN, so we must check this here. + */ + ir_mode *mode = get_irn_mode(sub); + tv = get_mode_null(mode); + + /* if the node was ONCE evaluated by all constants, but now + this breakes AND we cat by partition a different result, switch to bottom. + This happens because initially all nodes are in the same partition ... */ + if (node->by_all_const && node->type.tv != tv) + tv = tarval_bottom; + node->type.tv = tv; + } else { + node->type.tv = tarval_bottom; + } +} /* compute_Sub */ + +/** + * (Re-)compute the type for an Eor. Special case: both nodes are congruent. + * + * @param node the node + */ +static void compute_Eor(node_t *node) { + ir_node *eor = node->node; + node_t *l = get_irn_node(get_Eor_left(eor)); + node_t *r = get_irn_node(get_Eor_right(eor)); + lattice_elem_t a = l->type; + lattice_elem_t b = r->type; + tarval *tv; + + if (a.tv == tarval_top || b.tv == tarval_top) { + node->type.tv = tarval_top; + } else if (is_con(a) && is_con(b)) { + if (is_tarval(a.tv) && is_tarval(b.tv)) { + node->type.tv = tarval_eor(a.tv, b.tv); + } else if (is_tarval(a.tv) && tarval_is_null(a.tv)) { + node->type = b; + } else if (is_tarval(b.tv) && tarval_is_null(b.tv)) { + node->type = a; + } else { + node->type.tv = tarval_bottom; + } + node->by_all_const = 1; + } else if (r->part == l->part) { + ir_mode *mode = get_irn_mode(eor); + tv = get_mode_null(mode); + + /* if the node was ONCE evaluated by all constants, but now + this breakes AND we cat by partition a different result, switch to bottom. + This happens because initially all nodes are in the same partition ... */ + if (node->by_all_const && node->type.tv != tv) + tv = tarval_bottom; + node->type.tv = tv; + } else { + node->type.tv = tarval_bottom; + } +} /* compute_Eor */ + +/** + * (Re-)compute the type for Cmp. + * + * @param node the node + */ +static void compute_Cmp(node_t *node) { + ir_node *cmp = node->node; + node_t *l = get_irn_node(get_Cmp_left(cmp)); + node_t *r = get_irn_node(get_Cmp_right(cmp)); + lattice_elem_t a = l->type; + lattice_elem_t b = r->type; + + if (a.tv == tarval_top || b.tv == tarval_top) { +#ifdef WITH_UNKNOWN + /* + * Top is congruent to any other value, we can + * calculate the compare result. + */ + node->type.tv = tarval_b_true; +#else + node->type.tv = tarval_top; +#endif + } else if (is_con(a) && is_con(b)) { + /* both nodes are constants, we can probably do something */ + node->type.tv = tarval_b_true; + } else if (r->part == l->part) { + /* both nodes congruent, we can probably do something */ + node->type.tv = tarval_b_true; + } else { + node->type.tv = tarval_bottom; + } +} /* compute_Proj_Cmp */ + +/** + * (Re-)compute the type for a Proj(Cmp). + * + * @param node the node + * @param cond the predecessor Cmp node + */ +static void compute_Proj_Cmp(node_t *node, ir_node *cmp) { + ir_node *proj = node->node; + node_t *l = get_irn_node(get_Cmp_left(cmp)); + node_t *r = get_irn_node(get_Cmp_right(cmp)); + lattice_elem_t a = l->type; + lattice_elem_t b = r->type; + pn_Cmp pnc = get_Proj_proj(proj); + tarval *tv; + + if (a.tv == tarval_top || b.tv == tarval_top) { +#ifdef WITH_UNKNOWN + /* see above */ + tv = new_tarval_from_long((pnc & pn_Cmp_Eq) ^ pn_Cmp_Eq, mode_b); + goto not_equal; +#else + node->type.tv = tarval_top; +#endif + } else if (is_con(a) && is_con(b)) { + default_compute(node); + node->by_all_const = 1; + } else if (r->part == l->part && + (!mode_is_float(get_irn_mode(l->node)) || pnc == pn_Cmp_Lt || pnc == pn_Cmp_Gt)) { + /* + * BEWARE: a == a is NOT always True for floating Point values, as + * NaN != NaN is defined, so we must check this here. + */ + tv = new_tarval_from_long(pnc & pn_Cmp_Eq, mode_b); +#ifdef WITH_UNKNOWN +not_equal: +#endif + + /* if the node was ONCE evaluated by all constants, but now + this breakes AND we cat by partition a different result, switch to bottom. + This happens because initially all nodes are in the same partition ... */ + if (node->by_all_const && node->type.tv != tv) + tv = tarval_bottom; + node->type.tv = tv; + } else { + node->type.tv = tarval_bottom; + } +} /* compute_Proj_Cmp */ + +/** + * (Re-)compute the type for a Proj(Cond). + * + * @param node the node + * @param cond the predecessor Cond node + */ +static void compute_Proj_Cond(node_t *node, ir_node *cond) { + ir_node *proj = node->node; + long pnc = get_Proj_proj(proj); + ir_node *sel = get_Cond_selector(cond); + node_t *selector = get_irn_node(sel); + + if (get_irn_mode(sel) == mode_b) { + /* an IF */ + if (pnc == pn_Cond_true) { + if (selector->type.tv == tarval_b_false) { + node->type.tv = tarval_unreachable; + } else if (selector->type.tv == tarval_b_true) { + node->type.tv = tarval_reachable; + } else if (selector->type.tv == tarval_bottom) { + node->type.tv = tarval_reachable; + } else { + assert(selector->type.tv == tarval_top); + node->type.tv = tarval_unreachable; + } + } else { + assert(pnc == pn_Cond_false); + + if (selector->type.tv == tarval_b_false) { + node->type.tv = tarval_reachable; + } else if (selector->type.tv == tarval_b_true) { + node->type.tv = tarval_unreachable; + } else if (selector->type.tv == tarval_bottom) { + node->type.tv = tarval_reachable; + } else { + assert(selector->type.tv == tarval_top); + node->type.tv = tarval_unreachable; + } + } + } else { + /* an SWITCH */ + if (selector->type.tv == tarval_bottom) { + node->type.tv = tarval_reachable; + } else if (selector->type.tv == tarval_top) { + node->type.tv = tarval_unreachable; + } else { + long value = get_tarval_long(selector->type.tv); + if (pnc == get_Cond_defaultProj(cond)) { + /* default switch, have to check ALL other cases */ + int i; + + for (i = get_irn_n_outs(cond) - 1; i >= 0; --i) { + ir_node *succ = get_irn_out(cond, i); + + if (succ == proj) + continue; + if (value == get_Proj_proj(succ)) { + /* we found a match, will NOT take the default case */ + node->type.tv = tarval_unreachable; + return; + } + } + /* all cases checked, no match, will take default case */ + node->type.tv = tarval_reachable; + } else { + /* normal case */ + node->type.tv = value == pnc ? tarval_reachable : tarval_unreachable; + } + } + } +} /* compute_Proj_Cond */ + +/** + * (Re-)compute the type for a Proj-Node. + * + * @param node the node + */ +static void compute_Proj(node_t *node) { + ir_node *proj = node->node; + ir_mode *mode = get_irn_mode(proj); + node_t *block = get_irn_node(get_nodes_block(skip_Proj(proj))); + ir_node *pred = get_Proj_pred(proj); + + if (block->type.tv == tarval_unreachable) { + /* a Proj in a unreachable Block stay Top */ + node->type.tv = tarval_top; + return; + } + if (get_irn_node(pred)->type.tv == tarval_top) { + /* if the predecessor is Top, its Proj follow */ + node->type.tv = tarval_top; + return; + } + + if (mode == mode_M) { + /* mode M is always bottom */ + node->type.tv = tarval_bottom; + return; + } + if (mode != mode_X) { + if (is_Cmp(pred)) + compute_Proj_Cmp(node, pred); + else + default_compute(node); + return; + } + /* handle mode_X nodes */ + + switch (get_irn_opcode(pred)) { + case iro_Start: + /* the Proj_X from the Start is always reachable. + However this is already handled at the top. */ + node->type.tv = tarval_reachable; + break; + case iro_Cond: + compute_Proj_Cond(node, pred); + break; + default: + default_compute(node); + } +} /* compute_Proj */ + +/** + * (Re-)compute the type for a Confirm. + * + * @param node the node + */ +static void compute_Confirm(node_t *node) { + ir_node *confirm = node->node; + node_t *pred = get_irn_node(get_Confirm_value(confirm)); + + if (get_Confirm_cmp(confirm) == pn_Cmp_Eq) { + node_t *bound = get_irn_node(get_Confirm_bound(confirm)); + + if (is_con(bound->type)) { + /* is equal to a constant */ + node->type = bound->type; + return; + } + } + /* a Confirm is a copy OR a Const */ + node->type = pred->type; +} /* compute_Confirm */ + +/** + * (Re-)compute the type for a Max. + * + * @param node the node + */ +static void compute_Max(node_t *node) { + ir_node *op = node->node; + node_t *l = get_irn_node(get_binop_left(op)); + node_t *r = get_irn_node(get_binop_right(op)); + lattice_elem_t a = l->type; + lattice_elem_t b = r->type; + + if (a.tv == tarval_top || b.tv == tarval_top) { + node->type.tv = tarval_top; + } else if (is_con(a) && is_con(b)) { + /* both nodes are constants, we can probably do something */ + if (a.tv == b.tv) { + /* this case handles symconsts as well */ + node->type = a; + } else { + ir_mode *mode = get_irn_mode(op); + tarval *tv_min = get_mode_min(mode); + + if (a.tv == tv_min) + node->type = b; + else if (b.tv == tv_min) + node->type = a; + else if (is_tarval(a.tv) && is_tarval(b.tv)) { + if (tarval_cmp(a.tv, b.tv) & pn_Cmp_Gt) + node->type.tv = a.tv; + else + node->type.tv = b.tv; + } else { + node->type.tv = tarval_bad; + } + } + } else if (r->part == l->part) { + /* both nodes congruent, we can probably do something */ + node->type = a; + } else { + node->type.tv = tarval_bottom; + } +} /* compute_Max */ + +/** + * (Re-)compute the type for a Min. + * + * @param node the node + */ +static void compute_Min(node_t *node) { + ir_node *op = node->node; + node_t *l = get_irn_node(get_binop_left(op)); + node_t *r = get_irn_node(get_binop_right(op)); + lattice_elem_t a = l->type; + lattice_elem_t b = r->type; + + if (a.tv == tarval_top || b.tv == tarval_top) { + node->type.tv = tarval_top; + } else if (is_con(a) && is_con(b)) { + /* both nodes are constants, we can probably do something */ + if (a.tv == b.tv) { + /* this case handles symconsts as well */ + node->type = a; + } else { + ir_mode *mode = get_irn_mode(op); + tarval *tv_max = get_mode_max(mode); + + if (a.tv == tv_max) + node->type = b; + else if (b.tv == tv_max) + node->type = a; + else if (is_tarval(a.tv) && is_tarval(b.tv)) { + if (tarval_cmp(a.tv, b.tv) & pn_Cmp_Gt) + node->type.tv = a.tv; + else + node->type.tv = b.tv; + } else { + node->type.tv = tarval_bad; + } + } + } else if (r->part == l->part) { + /* both nodes congruent, we can probably do something */ + node->type = a; + } else { + node->type.tv = tarval_bottom; + } +} /* compute_Min */ + +/** + * (Re-)compute the type for a given node. + * + * @param node the node + */ +static void compute(node_t *node) { + compute_func func; + + if (is_no_Block(node->node)) { + node_t *block = get_irn_node(get_nodes_block(node->node)); + + if (block->type.tv == tarval_unreachable) { + node->type.tv = tarval_top; + return; + } + } + + func = (compute_func)node->node->op->ops.generic; + if (func != NULL) + func(node); +} /* compute */ + +/* + * Identity functions: Note that one might thing that identity() is just a + * synonym for equivalent_node(). While this is true, we cannot use it for the algorithm + * here, because it expects that the identity node is one of the inputs, which is NOT + * always true for equivalent_node() which can handle (and does sometimes) DAGs. + * So, we have our own implementation, which copies some parts of equivalent_node() + */ + +/** + * Calculates the Identity for Phi nodes + */ +static node_t *identity_Phi(node_t *node) { + ir_node *phi = node->node; + ir_node *block = get_nodes_block(phi); + node_t *n_part = NULL; + int i; + + for (i = get_Phi_n_preds(phi) - 1; i >= 0; --i) { + node_t *pred_X = get_irn_node(get_Block_cfgpred(block, i)); + + if (pred_X->type.tv == tarval_reachable) { + node_t *pred = get_irn_node(get_Phi_pred(phi, i)); + + if (n_part == NULL) + n_part = pred; + else if (n_part->part != pred->part) { + /* incongruent inputs, not a follower */ + return node; + } + } + } + /* if n_part is NULL here, all inputs path are dead, the Phi computes + * tarval_top, is in the TOP partition and should NOT being split! */ + assert(n_part != NULL); + return n_part; +} /* identity_Phi */ + +/** + * Calculates the Identity for commutative 0 neutral nodes. + */ +static node_t *identity_comm_zero_binop(node_t *node) { + ir_node *op = node->node; + node_t *a = get_irn_node(get_binop_left(op)); + node_t *b = get_irn_node(get_binop_right(op)); + ir_mode *mode = get_irn_mode(op); + tarval *zero; + + /* for FP these optimizations are only allowed if fp_strict_algebraic is disabled */ + if (mode_is_float(mode) && (get_irg_fp_model(current_ir_graph) & fp_strict_algebraic)) + return node; + + /* node: no input should be tarval_top, else the binop would be also + * Top and not being split. */ + zero = get_mode_null(mode); + if (a->type.tv == zero) + return b; + if (b->type.tv == zero) + return a; + return node; +} /* identity_comm_zero_binop */ + +/** + * Calculates the Identity for Shift nodes. + */ +static node_t *identity_shift(node_t *node) { + ir_node *op = node->node; + node_t *b = get_irn_node(get_binop_right(op)); + ir_mode *mode = get_irn_mode(b->node); + tarval *zero; + + /* node: no input should be tarval_top, else the binop would be also + * Top and not being split. */ + zero = get_mode_null(mode); + if (b->type.tv == zero) + return get_irn_node(get_binop_left(op)); + return node; +} /* identity_shift */ + +/** + * Calculates the Identity for Mul nodes. + */ +static node_t *identity_Mul(node_t *node) { + ir_node *op = node->node; + node_t *a = get_irn_node(get_Mul_left(op)); + node_t *b = get_irn_node(get_Mul_right(op)); + ir_mode *mode = get_irn_mode(op); + tarval *one; + + /* for FP these optimizations are only allowed if fp_strict_algebraic is disabled */ + if (mode_is_float(mode) && (get_irg_fp_model(current_ir_graph) & fp_strict_algebraic)) + return node; + + /* node: no input should be tarval_top, else the binop would be also + * Top and not being split. */ + one = get_mode_one(mode); + if (a->type.tv == one) + return b; + if (b->type.tv == one) + return a; + return node; +} /* identity_Mul */ + +/** + * Calculates the Identity for Sub nodes. + */ +static node_t *identity_Sub(node_t *node) { + ir_node *sub = node->node; + node_t *b = get_irn_node(get_Sub_right(sub)); + ir_mode *mode = get_irn_mode(sub); + + /* for FP these optimizations are only allowed if fp_strict_algebraic is disabled */ + if (mode_is_float(mode) && (get_irg_fp_model(current_ir_graph) & fp_strict_algebraic)) + return node; + + /* node: no input should be tarval_top, else the binop would be also + * Top and not being split. */ + if (b->type.tv == get_mode_null(mode)) + return get_irn_node(get_Sub_left(sub)); + return node; +} /* identity_Mul */ + +/** + * Calculates the Identity for And nodes. + */ +static node_t *identity_And(node_t *node) { + ir_node *and = node->node; + node_t *a = get_irn_node(get_And_left(and)); + node_t *b = get_irn_node(get_And_right(and)); + tarval *neutral = get_mode_all_one(get_irn_mode(and)); + + /* node: no input should be tarval_top, else the And would be also + * Top and not being split. */ + if (a->type.tv == neutral) + return b; + if (b->type.tv == neutral) + return a; + return node; +} /* identity_And */ + +/** + * Calculates the Identity for Confirm nodes. + */ +static node_t *identity_Confirm(node_t *node) { + ir_node *confirm = node->node; + + /* a Confirm is always a Copy */ + return get_irn_node(get_Confirm_value(confirm)); +} /* identity_Confirm */ + +/** + * Calculates the Identity for Mux nodes. + */ +static node_t *identity_Mux(node_t *node) { + ir_node *mux = node->node; + node_t *t = get_irn_node(get_Mux_true(mux)); + node_t *f = get_irn_node(get_Mux_false(mux)); + /*node_t *sel; */ + + if (t->part == f->part) + return t; + + /* for now, the 1-input identity is not supported */ +#if 0 + sel = get_irn_node(get_Mux_sel(mux)); + + /* Mux sel input is mode_b, so it is always a tarval */ + if (sel->type.tv == tarval_b_true) + return t; + if (sel->type.tv == tarval_b_false) + return f; +#endif + return node; +} /* identity_Mux */ + +/** + * Calculates the Identity for Min nodes. + */ +static node_t *identity_Min(node_t *node) { + ir_node *op = node->node; + node_t *a = get_irn_node(get_binop_left(op)); + node_t *b = get_irn_node(get_binop_right(op)); + ir_mode *mode = get_irn_mode(op); + tarval *tv_max; + + if (a->part == b->part) { + /* leader of multiple predecessors */ + return a; + } + + /* works even with NaN */ + tv_max = get_mode_max(mode); + if (a->type.tv == tv_max) + return b; + if (b->type.tv == tv_max) + return a; + return node; +} /* identity_Min */ + +/** + * Calculates the Identity for Max nodes. + */ +static node_t *identity_Max(node_t *node) { + ir_node *op = node->node; + node_t *a = get_irn_node(get_binop_left(op)); + node_t *b = get_irn_node(get_binop_right(op)); + ir_mode *mode = get_irn_mode(op); + tarval *tv_min; + + if (a->part == b->part) { + /* leader of multiple predecessors */ + return a; + } + + /* works even with NaN */ + tv_min = get_mode_min(mode); + if (a->type.tv == tv_min) + return b; + if (b->type.tv == tv_min) + return a; + return node; +} /* identity_Max */ + +/** + * Calculates the Identity for nodes. + */ +static node_t *identity(node_t *node) { + ir_node *irn = node->node; + + switch (get_irn_opcode(irn)) { + case iro_Phi: + return identity_Phi(node); + case iro_Mul: + return identity_Mul(node); + case iro_Add: + case iro_Or: + case iro_Eor: + return identity_comm_zero_binop(node); + case iro_Shr: + case iro_Shl: + case iro_Shrs: + case iro_Rotl: + return identity_shift(node); + case iro_And: + return identity_And(node); + case iro_Sub: + return identity_Sub(node); + case iro_Confirm: + return identity_Confirm(node); + case iro_Mux: + return identity_Mux(node); + case iro_Min: + return identity_Min(node); + case iro_Max: + return identity_Max(node); + default: + return node; + } +} /* identity */ + +/** + * Node follower is a (new) follower of leader, segregate Leader + * out edges. + */ +static void segregate_def_use_chain_1(const ir_node *follower, node_t *leader) { + ir_node *l = leader->node; + int j, i, n = get_irn_n_outs(l); + + DB((dbg, LEVEL_2, "%+F is a follower of %+F\n", follower, leader->node)); + /* The leader edges must remain sorted, but follower edges can + be unsorted. */ + for (i = leader->n_followers + 1; i <= n; ++i) { + if (l->out[i].use == follower) { + ir_def_use_edge t = l->out[i]; + + for (j = i - 1; j >= leader->n_followers + 1; --j) + l->out[j + 1] = l->out[j]; + ++leader->n_followers; + l->out[leader->n_followers] = t; + break; + } + } +} /* segregate_def_use_chain_1 */ + +/** + * Node follower is a (new) follower of leader, segregate Leader + * out edges. If follower is a n-congruent Input identity, all follower + * inputs congruent to follower are also leader. + * + * @param follower the follower IR node + */ +static void segregate_def_use_chain(const ir_node *follower) { + int i; + + for (i = get_irn_arity(follower) - 1; i >= 0; --i) { + node_t *pred = get_irn_node(get_irn_n(follower, i)); + + segregate_def_use_chain_1(follower, pred); + } +} /* segregate_def_use_chain */ + +/** + * Propagate constant evaluation. + * + * @param env the environment + */ +static void propagate(environment_t *env) { + partition_t *X, *Y; + node_t *x; + lattice_elem_t old_type; + node_t *fallen; + unsigned n_fallen, old_type_was_T_or_C; + int i; + + while (env->cprop != NULL) { + void *oldopcode = NULL; + + /* remove the first partition X from cprop */ + X = env->cprop; + X->on_cprop = 0; + env->cprop = X->cprop_next; + + old_type_was_T_or_C = X->type_is_T_or_C; + + DB((dbg, LEVEL_2, "Propagate type on part%d\n", X->nr)); + fallen = NULL; + n_fallen = 0; + while (! list_empty(&X->cprop)) { + /* remove the first Node x from X.cprop */ + x = list_entry(X->cprop.next, node_t, cprop_list); + //assert(x->part == X); + list_del(&x->cprop_list); + x->on_cprop = 0; + + if (x->is_follower && identity(x) == x) { + /* check the opcode first */ + if (oldopcode == NULL) { + oldopcode = lambda_opcode(get_first_node(X), env); + } + if (oldopcode != lambda_opcode(x, env)) { + if (x->on_fallen == 0) { + /* different opcode -> x falls out of this partition */ + x->next = fallen; + x->on_fallen = 1; + fallen = x; + ++n_fallen; + DB((dbg, LEVEL_2, "Add node %+F to fallen\n", x->node)); + } + } + + /* x will make the follower -> leader transition */ + follower_to_leader(x); + } + + /* compute a new type for x */ + old_type = x->type; + DB((dbg, LEVEL_3, "computing type of %+F\n", x->node)); + compute(x); + if (x->type.tv != old_type.tv) { + verify_type(old_type, x->type); + DB((dbg, LEVEL_2, "node %+F has changed type from %+F to %+F\n", x->node, old_type, x->type)); + + if (x->on_fallen == 0) { + /* Add x to fallen. Nodes might fall from T -> const -> _|_, so check that they are + not already on the list. */ + x->next = fallen; + x->on_fallen = 1; + fallen = x; + ++n_fallen; + DB((dbg, LEVEL_2, "Add node %+F to fallen\n", x->node)); + } + for (i = get_irn_n_outs(x->node) - 1; i >= 0; --i) { + ir_node *succ = get_irn_out(x->node, i); + node_t *y = get_irn_node(succ); + + /* Add y to y.partition.cprop. */ + add_to_cprop(y, env); + } + } + } + + if (n_fallen > 0 && n_fallen != X->n_leader) { + DB((dbg, LEVEL_2, "Splitting part%d by fallen\n", X->nr)); + Y = split(&X, fallen, env); + /* + * We have split out fallen node. The type of the result + * partition is NOT set yet. + */ + Y->type_is_T_or_C = 0; + } else { + Y = X; + } + /* remove the flags from the fallen list */ + for (x = fallen; x != NULL; x = x->next) + x->on_fallen = 0; + + if (old_type_was_T_or_C) { + node_t *y, *tmp; + + if (Y->on_worklist == 0) + add_to_worklist(Y, env); + + /* check if some nodes will make the leader -> follower transition */ + list_for_each_entry_safe(node_t, y, tmp, &Y->Leader, node_list) { + if (y->type.tv != tarval_top && ! is_con(y->type)) { + node_t *eq_node = identity(y); + + if (eq_node != y && eq_node->part == y->part) { + DB((dbg, LEVEL_2, "Node %+F is a follower of %+F\n", y->node, eq_node->node)); + /* move to Follower */ + y->is_follower = 1; + list_del(&y->node_list); + list_add_tail(&y->node_list, &Y->Follower); + --Y->n_leader; + + segregate_def_use_chain(y->node); + } + } + } + } + split_by(Y, env); + } +} /* propagate */ + +/** + * Get the leader for a given node from its congruence class. + * + * @param irn the node + */ +static ir_node *get_leader(node_t *node) { + partition_t *part = node->part; + + if (part->n_leader > 1 || node->is_follower) { + if (node->is_follower) { + DB((dbg, LEVEL_2, "Replacing follower %+F\n", node->node)); + } + else + DB((dbg, LEVEL_2, "Found congruence class for %+F\n", node->node)); + + return get_first_node(part)->node; + } + return node->node; +} /* get_leader */ + +/** + * Return non-zero if the control flow predecessor node pred + * is the only reachable control flow exit of its block. + * + * @param pred the control flow exit + */ +static int can_exchange(ir_node *pred) { + if (is_Start(pred)) + return 0; + else if (is_Jmp(pred)) + return 1; + else if (get_irn_mode(pred) == mode_T) { + int i, k; + + /* if the predecessor block has more than one + reachable outputs we cannot remove the block */ + k = 0; + for (i = get_irn_n_outs(pred) - 1; i >= 0; --i) { + ir_node *proj = get_irn_out(pred, i); + node_t *node; + + /* skip non-control flow Proj's */ + if (get_irn_mode(proj) != mode_X) + continue; + + node = get_irn_node(proj); + if (node->type.tv == tarval_reachable) { + if (++k > 1) + return 0; + } + } + return 1; + } + return 0; +} /* can_exchange */ + +/** + * Block Post-Walker, apply the analysis results on control flow by + * shortening Phi's and Block inputs. + */ +static void apply_cf(ir_node *block, void *ctx) { + environment_t *env = ctx; + node_t *node = get_irn_node(block); + int i, j, k, n; + ir_node **ins, **in_X; + ir_node *phi, *next; + + n = get_Block_n_cfgpreds(block); + + if (node->type.tv == tarval_unreachable) { + env->modified = 1; + + for (i = n - 1; i >= 0; --i) { + ir_node *pred = get_Block_cfgpred(block, i); + + if (! is_Bad(pred)) { + node_t *pred_bl = get_irn_node(get_nodes_block(skip_Proj(pred))); + + if (pred_bl->flagged == 0) { + pred_bl->flagged = 3; + + if (pred_bl->type.tv == tarval_reachable) { + /* + * We will remove an edge from block to its pred. + * This might leave the pred block as an endless loop + */ + if (! is_backedge(block, i)) + keep_alive(pred_bl->node); + } + } + } + } + + /* the EndBlock is always reachable even if the analysis + finds out the opposite :-) */ + if (block != get_irg_end_block(current_ir_graph)) { + /* mark dead blocks */ + set_Block_dead(block); + DB((dbg, LEVEL_1, "Removing dead %+F\n", block)); + } else { + /* the endblock is unreachable */ + set_irn_in(block, 0, NULL); + } + return; + } + + if (n == 1) { + /* only one predecessor combine */ + ir_node *pred = skip_Proj(get_Block_cfgpred(block, 0)); + + if (can_exchange(pred)) { + ir_node *new_block = get_nodes_block(pred); + DB((dbg, LEVEL_1, "Fuse %+F with %+F\n", block, new_block)); + DBG_OPT_COMBO(block, new_block, FS_OPT_COMBO_CF); + exchange(block, new_block); + node->node = new_block; + env->modified = 1; + } + return; + } + + NEW_ARR_A(ir_node *, in_X, n); + k = 0; + for (i = 0; i < n; ++i) { + ir_node *pred = get_Block_cfgpred(block, i); + node_t *node = get_irn_node(pred); + + if (node->type.tv == tarval_reachable) { + in_X[k++] = pred; + } else { + DB((dbg, LEVEL_1, "Removing dead input %d from %+F (%+F)\n", i, block, pred)); + if (! is_Bad(pred)) { + node_t *pred_bl = get_irn_node(get_nodes_block(skip_Proj(pred))); + + if (pred_bl->flagged == 0) { + pred_bl->flagged = 3; + + if (pred_bl->type.tv == tarval_reachable) { + /* + * We will remove an edge from block to its pred. + * This might leave the pred block as an endless loop + */ + if (! is_backedge(block, i)) + keep_alive(pred_bl->node); + } + } + } + } + } + if (k >= n) + return; + + NEW_ARR_A(ir_node *, ins, n); + for (phi = get_Block_phis(block); phi != NULL; phi = next) { + node_t *node = get_irn_node(phi); + + next = get_Phi_next(phi); + if (is_tarval(node->type.tv) && tarval_is_constant(node->type.tv)) { + /* this Phi is replaced by a constant */ + tarval *tv = node->type.tv; + ir_node *c = new_r_Const(current_ir_graph, block, get_tarval_mode(tv), tv); + + set_irn_node(c, node); + node->node = c; + DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", phi, c)); + DBG_OPT_COMBO(phi, c, FS_OPT_COMBO_CONST); + exchange(phi, c); + env->modified = 1; + } else { + j = 0; + for (i = 0; i < n; ++i) { + node_t *pred = get_irn_node(get_Block_cfgpred(block, i)); + + if (pred->type.tv == tarval_reachable) { + ins[j++] = get_Phi_pred(phi, i); + } + } + if (j == 1) { + /* this Phi is replaced by a single predecessor */ + ir_node *s = ins[0]; + node_t *phi_node = get_irn_node(phi); + + node->node = s; + DB((dbg, LEVEL_1, "%+F is replaced by %+F because of cf change\n", phi, s)); + DBG_OPT_COMBO(phi, s, FS_OPT_COMBO_FOLLOWER); + exchange(phi, s); + phi_node->node = s; + env->modified = 1; + } else { + set_irn_in(phi, j, ins); + env->modified = 1; + } + } + } + + if (k == 1) { + /* this Block has only one live predecessor */ + ir_node *pred = skip_Proj(in_X[0]); + + if (can_exchange(pred)) { + ir_node *new_block = get_nodes_block(pred); + DBG_OPT_COMBO(block, new_block, FS_OPT_COMBO_CF); + exchange(block, new_block); + node->node = new_block; + env->modified = 1; + } + } else { + set_irn_in(block, k, in_X); + env->modified = 1; + } +} + +/** + * Post-Walker, apply the analysis results; + */ +static void apply_result(ir_node *irn, void *ctx) { + environment_t *env = ctx; + node_t *node = get_irn_node(irn); + + if (is_Block(irn) || is_End(irn) || is_Bad(irn)) { + /* blocks already handled, do not touch the End node */ + } else { + node_t *block = get_irn_node(get_nodes_block(irn)); + + if (block->type.tv == tarval_unreachable) { + ir_node *bad = get_irg_bad(current_ir_graph); + + /* here, bad might already have a node, but this can be safely ignored + as long as bad has at least ONE valid node */ + set_irn_node(bad, node); + node->node = bad; + DB((dbg, LEVEL_1, "%+F is unreachable\n", irn)); + exchange(irn, bad); + env->modified = 1; + } + else if (node->type.tv == tarval_unreachable) { + /* don't kick away Unknown */ + if (! is_Unknown(irn)) { + ir_node *bad = get_irg_bad(current_ir_graph); + + /* see comment above */ + set_irn_node(bad, node); + node->node = bad; + DB((dbg, LEVEL_1, "%+F is unreachable\n", irn)); + exchange(irn, bad); + env->modified = 1; + } + } + else if (get_irn_mode(irn) == mode_X) { + if (is_Proj(irn)) { + /* leave or Jmp */ + ir_node *cond = get_Proj_pred(irn); + + if (is_Cond(cond)) { + node_t *sel = get_irn_node(get_Cond_selector(cond)); + + if (is_tarval(sel->type.tv) && tarval_is_constant(sel->type.tv)) { + /* Cond selector is a constant and the Proj is reachable, make a Jmp */ + ir_node *jmp = new_r_Jmp(current_ir_graph, block->node); + set_irn_node(jmp, node); + node->node = jmp; + DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, jmp)); + DBG_OPT_COMBO(irn, jmp, FS_OPT_COMBO_CF); + exchange(irn, jmp); + env->modified = 1; + } + } + } + } else { + /* normal data node */ + if (is_tarval(node->type.tv) && tarval_is_constant(node->type.tv)) { + tarval *tv = node->type.tv; + + /* + * Beware: never replace mode_T nodes by constants. Currently we must mark + * mode_T nodes with constants, but do NOT replace them. + */ + if (! is_Const(irn) && get_irn_mode(irn) != mode_T) { + /* can be replaced by a constant */ + ir_node *c = new_r_Const(current_ir_graph, block->node, get_tarval_mode(tv), tv); + set_irn_node(c, node); + node->node = c; + DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, c)); + DBG_OPT_COMBO(irn, c, FS_OPT_COMBO_CONST); + exchange(irn, c); + env->modified = 1; + } + } else if (is_entity(node->type.sym.entity_p)) { + if (! is_SymConst(irn)) { + /* can be replaced by a Symconst */ + ir_node *symc = new_r_SymConst(current_ir_graph, block->node, get_irn_mode(irn), node->type.sym, symconst_addr_ent); + set_irn_node(symc, node); + node->node = symc; + + DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, symc)); + DBG_OPT_COMBO(irn, symc, FS_OPT_COMBO_CONST); + exchange(irn, symc); + env->modified = 1; + } + } else if (is_Confirm(irn)) { + /* Confirms are always follower, but do not kill them here */ + } else { + ir_node *leader = get_leader(node); + + if (leader != irn) { + DB((dbg, LEVEL_1, "%+F from part%d is replaced by %+F\n", irn, node->part->nr, leader)); + if (node->is_follower) + DBG_OPT_COMBO(irn, leader, FS_OPT_COMBO_FOLLOWER); + else + DBG_OPT_COMBO(irn, leader, FS_OPT_COMBO_CONGRUENT); + exchange(irn, leader); + env->modified = 1; + } + } + } + } +} /* apply_result */ + +/** + * Fix the keep-alives by deleting unreachable ones. + */ +static void apply_end(ir_node *end, environment_t *env) { + int i, j, n = get_End_n_keepalives(end); + ir_node **in; + + if (n > 0) + NEW_ARR_A(ir_node *, in, n); + + /* fix the keep alive */ + for (i = j = 0; i < n; i++) { + ir_node *ka = get_End_keepalive(end, i); + node_t *node = get_irn_node(ka); + + if (! is_Block(ka)) + node = get_irn_node(get_nodes_block(ka)); + + if (node->type.tv != tarval_unreachable) + in[j++] = ka; + } + if (j != n) { + set_End_keepalives(end, j, in); + env->modified = 1; + } +} /* apply_end */ + +#define SET(code) op_##code->ops.generic = (op_func)compute_##code + +/** + * sets the generic functions to compute. + */ +static void set_compute_functions(void) { + int i; + + /* set the default compute function */ + for (i = get_irp_n_opcodes() - 1; i >= 0; --i) { + ir_op *op = get_irp_opcode(i); + op->ops.generic = (op_func)default_compute; + } + + /* set specific functions */ + SET(Block); + SET(Unknown); + SET(Bad); + SET(Jmp); + SET(Phi); + SET(Add); + SET(Sub); + SET(Eor); + SET(SymConst); + SET(Cmp); + SET(Proj); + SET(Confirm); + SET(End); + + if (op_Max != NULL) + SET(Max); + if (op_Min != NULL) + SET(Min); + +} /* set_compute_functions */ + +static int dump_partition_hook(FILE *F, ir_node *n, ir_node *local) { +#ifdef DEBUG_libfirm + ir_node *irn = local != NULL ? local : n; + node_t *node = get_irn_node(irn); + + ir_fprintf(F, "info2 : \"partition %u type %+F\"\n", node->part->nr, node->type); + return 1; +#endif } + +void combo(ir_graph *irg) { + environment_t env; + ir_node *initial_bl; + node_t *start; + ir_graph *rem = current_ir_graph; + + current_ir_graph = irg; + + /* register a debug mask */ + FIRM_DBG_REGISTER(dbg, "firm.opt.combo"); + //firm_dbg_set_mask(dbg, SET_LEVEL_3); + + DB((dbg, LEVEL_1, "Doing COMBO for %+F\n", irg)); + + obstack_init(&env.obst); + env.worklist = NULL; + env.cprop = NULL; + env.touched = NULL; + env.initial = NULL; +#ifdef DEBUG_libfirm + env.dbg_list = NULL; +#endif + env.opcode2id_map = new_set(cmp_opcode, iro_Last * 4); + env.type2id_map = pmap_create(); + env.end_idx = get_opt_global_cse() ? 0 : -1; + env.lambda_input = 0; + env.nonstd_cond = 0; + env.modified = 0; + + assure_irg_outs(irg); + assure_cf_loop(irg); + + + /* we have our own value_of function */ + set_value_of_func(get_node_tarval); + + set_compute_functions(); + DEBUG_ONLY(part_nr = 0); + + ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK); + + /* create the initial partition and place it on the work list */ + env.initial = new_partition(&env); + add_to_worklist(env.initial, &env); + irg_walk_graph(irg, init_block_phis, create_initial_partitions, &env); + +#ifdef WITH_UNKNOWN + tarval_UNKNOWN = env.nonstd_cond ? tarval_bad : tarval_top; +#else + tarval_UNKNOWN = tarval_bad; +#endif + + /* all nodes on the initial partition have type Top */ + env.initial->type_is_T_or_C = 1; + + /* Place the START Node's partition on cprop. + Place the START Node on its local worklist. */ + initial_bl = get_irg_start_block(irg); + start = get_irn_node(initial_bl); + add_to_cprop(start, &env); + + do { + propagate(&env); + if (env.worklist != NULL) + cause_splits(&env); + } while (env.cprop != NULL || env.worklist != NULL); + + dump_all_partitions(&env); + check_all_partitions(&env); + +#if 0 + set_dump_node_vcgattr_hook(dump_partition_hook); + dump_ir_block_graph(irg, "-partition"); + set_dump_node_vcgattr_hook(NULL); +#else + (void)dump_partition_hook; +#endif + + /* apply the result */ + irg_block_walk_graph(irg, NULL, apply_cf, &env); + irg_walk_graph(irg, NULL, apply_result, &env); + apply_end(get_irg_end(irg), &env); + + if (env.modified) { + /* control flow might changed */ + set_irg_outs_inconsistent(irg); + set_irg_extblk_inconsistent(irg); + set_irg_doms_inconsistent(irg); + set_irg_loopinfo_inconsistent(irg); + } + + ir_free_resources(irg, IR_RESOURCE_IRN_LINK); + + pmap_destroy(env.type2id_map); + del_set(env.opcode2id_map); + obstack_free(&env.obst, NULL); + + /* restore value_of() default behavior */ + set_value_of_func(NULL); + current_ir_graph = rem; +} /* combo */