From 679e434a639f3cbf7876c6ee8fd45f69e74b69bd Mon Sep 17 00:00:00 2001 From: Michael Beck Date: Wed, 8 Oct 2008 00:06:47 +0000 Subject: [PATCH] - Add support for commutative congruences: Add(a,b) and Add(b,a) are congruent now - add some explaining comment for the "wrong opcode after split_by(lambda_opcode) problem - new checker added - improved debug output [r22595] --- ir/opt/combo.c | 254 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 245 insertions(+), 9 deletions(-) diff --git a/ir/opt/combo.c b/ir/opt/combo.c index 099091c7e..daac64797 100644 --- a/ir/opt/combo.c +++ b/ir/opt/combo.c @@ -23,6 +23,13 @@ * @author Michael Beck * @version $Id$ * + * This is a slightly enhanced version of Cliff Clicks combo algorithm + * - support for commutative node is added, add(a,b) and add(b,a) ARE congruent + * - supports all Firm direct (by a data edge) identities except Mux + * (Mux can be a 2-input or 1-input identity, only 2-input is implemented yet) + * - supports Confirm nodes (handle them like COpies but do NOT remove them) + * - support for global congruences is implemented but not tested yet + * * 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". @@ -168,6 +175,7 @@ typedef struct environment_t { 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. */ + char commutative; /**< Set, if commutation nodes should be handled specially. */ #ifdef DEBUG_libfirm partition_t *dbg_list; /**< List of all partitions. */ #endif @@ -187,6 +195,9 @@ typedef void *(*what_func)(const node_t *node, environment_t *env); /** The debug module handle. */ DEBUG_ONLY(static firm_dbg_module_t *dbg;) +/** The what reason. */ +DEBUG_ONLY(static const char *what_reason;) + /** Next partition number. */ DEBUG_ONLY(static unsigned part_nr = 0); @@ -219,6 +230,54 @@ static void check_partition(const partition_t *T) { } } /* check_partition */ +/** + * check that all leader nodes in the partition have the same opcode. + */ +static void check_opcode(const partition_t *Z) { + node_t *node; + opcode_key_t key; + int first = 1; + + list_for_each_entry(node_t, node, &Z->Leader, node_list) { + ir_node *irn = node->node; + + if (first) { + 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; + } + first = 0; + } else { + assert(key.code == get_irn_opcode(irn)); + assert(key.mode == get_irn_mode(irn)); + assert(key.arity == get_irn_arity(irn)); + + switch (get_irn_opcode(irn)) { + case iro_Proj: + assert(key.u.proj == get_Proj_proj(irn)); + break; + case iro_Sel: + assert(key.u.ent == get_Sel_entity(irn)); + break; + default: + break; + } + } + } +} /* check_opcode */ + static void check_all_partitions(environment_t *env) { partition_t *P; node_t *node; @@ -226,6 +285,8 @@ static void check_all_partitions(environment_t *env) { #ifdef DEBUG_libfirm for (P = env->dbg_list; P != NULL; P = P->dbg_next) { check_partition(P); + if (! P->type_is_T_or_C) + check_opcode(P); list_for_each_entry(node_t, node, &P->Follower, node_list) { node_t *leader = identity(node); @@ -334,11 +395,24 @@ static void dump_all_partitions(const environment_t *env) { dump_partition("", P); } +/** + * Sump a split list. + */ +static void dump_split_list(const partition_t *list) { + const partition_t *p; + + DB((dbg, LEVEL_2, "Split by %s produced = {\n", what_reason)); + for (p = list; p != NULL; p = p->split_next) + DB((dbg, LEVEL_2, "part%u, ", p->nr)); + DB((dbg, LEVEL_2, "\n}\n")); +} + #else #define dump_partition(msg, part) #define dump_race_list(msg, list) #define dump_list(msg, list) #define dump_all_partitions(env) +#define dump_split_list(list) #endif #if defined(VERIFY_MONOTONE) && defined (DEBUG_libfirm) @@ -429,7 +503,7 @@ static listmap_entry_t *listmap_find(listmap_t *map, void *id) { * @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); + return (entry->mode - (ir_mode *)0) * 9 + entry->code + entry->u.proj * 3 + HASH_PTR(entry->u.ent) + entry->arity; } /* opcode_hash */ /** @@ -1128,7 +1202,7 @@ static partition_t *split(partition_t **pX, node_t *gg, environment_t *env) { */ if (transitions) { /* place partitions on the cprop list */ - if (X_prime->on_cprop == 0) { + if (X_prime->on_cprop == 0) { X_prime->cprop_next = env->cprop; env->cprop = X_prime; X_prime->on_cprop = 1; @@ -1228,6 +1302,11 @@ static void collect_touched(list_head *list, int idx, environment_t *env) { succ = edge->use; + /* only non-commutative nodes */ + if (env->commutative && + (idx == 0 || idx == 1) && is_op_commutative(get_irn_op(succ))) + continue; + /* 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) @@ -1242,7 +1321,7 @@ static void collect_touched(list_head *list, int idx, environment_t *env) { if (is_constant_type(y->type)) { ir_opcode code = get_irn_opcode(succ); - if (code == iro_Sub || code == iro_Eor || code == iro_Cmp) + if (code == iro_Sub || code == iro_Cmp) add_to_cprop(y, env); } @@ -1256,6 +1335,57 @@ static void collect_touched(list_head *list, int idx, environment_t *env) { } } /* collect_touched */ +/** + * Collect commutative nodes to the touched list. + * + * @param list the list which contains the nodes that must be evaluated + * @param env the environment + */ +static void collect_commutative_touched(list_head *list, environment_t *env) { + node_t *x, *y; + + list_for_each_entry(node_t, x, list, node_list) { + int num_edges; + + num_edges = get_irn_n_outs(x->node); + + x->next_edge = x->n_followers + 1; + + /* 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 > 1) + break; + + ++x->next_edge; + if (edge->pos < 0) + continue; + + succ = edge->use; + + /* only commutative nodes */ + if (!is_op_commutative(get_irn_op(succ))) + continue; + + y = get_irn_node(succ); + if (is_constant_type(y->type)) { + ir_opcode code = get_irn_opcode(succ); + if (code == iro_Eor) + 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)) { + add_to_touched(y, env); + } + } + } +} /* collect_commutative_touched */ + /** * Split the partitions if caused by the first entry on the worklist. * @@ -1272,6 +1402,44 @@ static void cause_splits(environment_t *env) { dump_partition("Cause_split: ", X); + if (env->commutative) { + /* handle commutative nodes first */ + + /* empty the touched set: already done, just clear the list */ + env->touched = NULL; + + collect_commutative_touched(&X->Leader, env); + collect_commutative_touched(&X->Follower, 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); + } + } + /* 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 */ @@ -1354,7 +1522,7 @@ static partition_t *split_by_what(partition_t *X, what_func What, S = iter->list; /* Add SPLIT( X, S ) to P. */ - DB((dbg, LEVEL_2, "Split part%d by what\n", X->nr)); + DB((dbg, LEVEL_2, "Split part%d by WHAT = %s\n", X->nr, what_reason)); R = split(&X, S, env); R->split_next = *P; *P = R; @@ -1407,7 +1575,13 @@ static void *lambda_partition(const node_t *node, environment_t *env) { int i = env->lambda_input; if (i >= get_irn_arity(node->node)) { - /* we are outside the allowed range */ + /* + * We are outside the allowed range: This can happen even + * if we have split by opcode first: doing so might move Followers + * to Leaders and those will have a different opcode! + * Note that in this case the partition is on the cprop list and will be + * split again. + */ return NULL; } @@ -1422,6 +1596,58 @@ static void *lambda_partition(const node_t *node, environment_t *env) { return p->part; } /* lambda_partition */ +/** lambda n.(n[i].partition) for commutative nodes */ +static void *lambda_commutative_partition(const node_t *node, environment_t *env) { + ir_node *irn = node->node; + ir_node *skipped = skip_Proj(irn); + ir_node *pred, *left, *right; + node_t *p; + partition_t *pl, *pr; + int i = env->lambda_input; + + if (i >= get_irn_arity(node->node)) { + /* + * We are outside the allowed range: This can happen even + * if we have split by opcode first: doing so might move Followers + * to Leaders and those will have a different opcode! + * Note that in this case the partition is on the cprop list and will be + * split again. + */ + 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; + + if (i == -1) { + pred = get_irn_n(skipped, i); + p = get_irn_node(pred); + return p->part; + } + + if (is_op_commutative(get_irn_op(irn))) { + /* normalize partition order by returning the "smaller" on input 0, + the "bigger" on input 1. */ + left = get_binop_left(irn); + pl = get_irn_node(left)->part; + right = get_binop_right(irn); + pr = get_irn_node(right)->part; + + if (i == 0) + return pl < pr ? pl : pr; + else + return pl > pr ? pl : pr; + } else { + /* a not split out Follower */ + pred = get_irn_n(irn, i); + p = get_irn_node(pred); + + return p->part; + } +} /* lambda_commutative_partition */ + /** * Returns true if a type is a constant. */ @@ -1451,8 +1677,9 @@ static void split_by(partition_t *X, environment_t *env) { return; } - DB((dbg, LEVEL_2, "WHAT = lambda n.(n.type) on part%d\n", X->nr)); + DEBUG_ONLY(what_reason = "lambda n.(n.type)";) P = split_by_what(X, lambda_type, &P, env); + dump_split_list(P); /* adjust the type tags, we have split partitions by type */ for (I = P; I != NULL; I = I->split_next) { @@ -1469,8 +1696,9 @@ static void split_by(partition_t *X, environment_t *env) { 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)); + DEBUG_ONLY(what_reason = "lambda n.(n.opcode)";) Q = split_by_what(Y, lambda_opcode, &Q, env); + dump_split_list(Q); do { partition_t *Z = Q; @@ -1480,6 +1708,11 @@ static void split_by(partition_t *X, environment_t *env) { const node_t *first = get_first_node(Z); int arity = get_irn_arity(first->node); partition_t *R, *S; + what_func what = lambda_partition; + DEBUG_ONLY(char buf[64];) + + if (env->commutative && is_op_commutative(get_irn_op(first->node))) + what = lambda_commutative_partition; /* * BEWARE: during splitting by input 2 for instance we might @@ -1496,8 +1729,10 @@ static void split_by(partition_t *X, environment_t *env) { 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); + DEBUG_ONLY(snprintf(buf, sizeof(buf), "lambda n.(n[%d].partition)", input);) + DEBUG_ONLY(what_reason = buf;) + S = split_by_what(Z_prime, what, &S, env); + dump_split_list(S); } else { Z_prime->split_next = S; S = Z_prime; @@ -2993,6 +3228,7 @@ void combo(ir_graph *irg) { env.end_idx = get_opt_global_cse() ? 0 : -1; env.lambda_input = 0; env.nonstd_cond = 0; + env.commutative = 1; env.modified = 0; assure_irg_outs(irg); -- 2.20.1