X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbespill.c;h=aed7513e00092546e122d9e534b50e3ba77eb33e;hb=6ee1fce95429dbf57fda4455ca5f2cf011ac8190;hp=e003a2de4e0bbaac91e38a2bec3b8120f7d19a4b;hpb=9a616d42cec598933c021908880c8c48500a2112;p=libfirm diff --git a/ir/be/bespill.c b/ir/be/bespill.c index e003a2de4..aed7513e0 100644 --- a/ir/be/bespill.c +++ b/ir/be/bespill.c @@ -1,922 +1,239 @@ +/* + * This file is part of libFirm. + * Copyright (C) 2012 University of Karlsruhe. + */ + /** - * Author: Daniel Grund, Sebastian Hack - * Date: 29.09.2005 - * Copyright: (c) Universitaet Karlsruhe - * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE. + * @file + * @brief Spill module selection; Preparation steps + * @author Matthias Braun + * @date 29.09.2005 */ -#ifdef HAVE_CONFIG_H #include "config.h" -#endif -#include - -#include "pset.h" -#include "irnode_t.h" -#include "ircons_t.h" -#include "iredges_t.h" -#include "ident_t.h" -#include "type_t.h" -#include "entity_t.h" +#include "irtools.h" #include "debug.h" +#include "iredges_t.h" +#include "raw_bitset.h" +#include "statev_t.h" #include "irgwalk.h" -#include "array.h" -#include "pdeq.h" -#include "belive_t.h" -#include "besched_t.h" #include "bespill.h" -#include "benode_t.h" -#include "bechordal_t.h" - -/* This enables re-computation of values. Current state: Unfinished and buggy. */ -#undef BUGGY_REMAT - -typedef struct _reloader_t reloader_t; -typedef struct _spill_info_t spill_info_t; - -struct _reloader_t { - reloader_t *next; - ir_node *reloader; -}; +#include "bemodule.h" +#include "be.h" +#include "belive_t.h" +#include "beirg.h" +#include "bearch.h" +#include "benode.h" +#include "besched.h" +#include "bera.h" +#include "beintlive_t.h" -struct _spill_info_t { - ir_node *spilled_node; - reloader_t *reloaders; -}; +#include "lc_opts.h" +#include "lc_opts_enum.h" -typedef struct _spill_ctx_t { - ir_node *spilled; /**< The spilled node. */ - ir_node *user; /**< The node this spill is for. */ - ir_node *spill; /**< The spill itself. */ -} spill_ctx_t; +DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;) -struct _spill_env_t { +typedef struct be_pre_spill_env_t { + ir_graph *irg; const arch_register_class_t *cls; - const be_chordal_env_t *chordal_env; - struct obstack obst; - set *spill_ctxs; - set *spills; /**< all spill_info_t's, which must be placed */ - pset *mem_phis; /**< set of all special spilled phis. allocated and freed separately */ - ir_node **copies; /**< set of copies placed because of phi spills */ - DEBUG_ONLY(firm_dbg_module_t *dbg;) -}; - -/* associated Phi -> Spill*/ -typedef struct _phi_spill_assoc_t { - ir_node *phi; - ir_node *spill; -} phi_spill_assoc_t; - -/** - * Compare two Phi->Spill associations. - */ -static int cmp_phi_spill_assoc(const void *a, const void *b, size_t n) { - const phi_spill_assoc_t *p1 = a; - const phi_spill_assoc_t *p2 = b; - return p1->phi != p2->phi; -} - -/** - * compare two spill contexts. - */ -static int cmp_spillctx(const void *a, const void *b, size_t n) { - const spill_ctx_t *p = a; - const spill_ctx_t *q = b; - return p->user != q->user || p->spilled != q->spilled; -} - -/** - * Compare two spill infos. - */ -static int cmp_spillinfo(const void *x, const void *y, size_t size) { - const spill_info_t *xx = x; - const spill_info_t *yy = y; - return xx->spilled_node != yy->spilled_node; -} - -DEBUG_ONLY( -/* Sets the debug module of a spill environment. */ -void be_set_spill_env_dbg_module(spill_env_t *env, firm_dbg_module_t *dbg) { - env->dbg = dbg; -} -) - -/* Creates a new spill environment. */ -spill_env_t *be_new_spill_env(const be_chordal_env_t *chordal_env) { - spill_env_t *env = xmalloc(sizeof(env[0])); - env->spill_ctxs = new_set(cmp_spillctx, 1024); - env->spills = new_set(cmp_spillinfo, 1024); - env->cls = chordal_env->cls; - env->chordal_env = chordal_env; - env->mem_phis = pset_new_ptr_default(); - env->copies = NEW_ARR_F(ir_node*, 0); - obstack_init(&env->obst); - return env; -} - -/* Deletes a spill environment. */ -void be_delete_spill_env(spill_env_t *env) { - del_set(env->spill_ctxs); - del_set(env->spills); - del_pset(env->mem_phis); - DEL_ARR_F(env->copies); - obstack_free(&env->obst, NULL); - free(env); -} - -/** - * Returns a spill context. If the context did not exists, create one. - * - * @param sc the set containing all spill contexts - * @param to_spill the node that should be spilled - * @param ctx_irn an user of the spilled node - * - * @return a spill context. - */ -static spill_ctx_t *be_get_spill_ctx(set *sc, ir_node *to_spill, ir_node *ctx_irn) { - spill_ctx_t templ; - - templ.spilled = to_spill; - templ.user = ctx_irn; - templ.spill = NULL; - - return set_insert(sc, &templ, sizeof(templ), HASH_COMBINE(HASH_PTR(to_spill), HASH_PTR(ctx_irn))); -} - -/** - * Schedules a node after an instruction. (That is the place after all projs and phis - * that are scheduled after the instruction) - */ -static void sched_add_after_insn(ir_node *sched_after, ir_node *node) { - ir_node *next = sched_next(sched_after); - while(!sched_is_end(next)) { - if(!is_Proj(next) && !is_Phi(next)) - break; - next = sched_next(next); - } - - if(sched_is_end(next)) { - next = sched_last(get_nodes_block(sched_after)); - sched_add_after(next, node); - } else { - sched_add_before(next, node); - } -} - -/** - * Creates a spill. - * - * @param senv the spill environment - * @param irn the node that should be spilled - * @param ctx_irn an user of the spilled node - * - * @return a be_Spill node - */ -static ir_node *be_spill_irn(spill_env_t *senv, ir_node *irn, ir_node *ctx_irn) { - spill_ctx_t *ctx; - const be_main_env_t *env = senv->chordal_env->birg->main_env; - DBG((senv->dbg, LEVEL_1, "%+F in ctx %+F\n", irn, ctx_irn)); - - // Has the value already been spilled? - ctx = be_get_spill_ctx(senv->spill_ctxs, irn, ctx_irn); - if(ctx->spill) - return ctx->spill; - - /* Trying to spill an already spilled value, no need for a new spill - * node then, we can simply connect to the same one for this reload +} be_pre_spill_env_t; + +static void prepare_constr_insn(be_pre_spill_env_t *env, ir_node *node) +{ + const arch_register_class_t *cls = env->cls; + ir_node *block = get_nodes_block(node); + const ir_graph *irg = env->irg; + be_irg_t *birg = be_birg_from_irg(irg); + be_lv_t *lv = be_get_irg_liveness(irg); + unsigned *def_constr = NULL; + int arity = get_irn_arity(node); + + /* Insert a copy for constraint inputs attached to a value which can't + * fulfill the constraint + * (typical example: stack pointer as input to copyb) + * TODO: This really just checks precolored registers at the moment and + * ignores the general case of not matching in/out constraints */ - if(be_is_Reload(irn)) { - return get_irn_n(irn, be_pos_Reload_mem); - } - - ctx->spill = be_spill(env->arch_env, irn, ctx_irn); - sched_add_after_insn(irn, ctx->spill); - - return ctx->spill; -} - -/** - * Removes all copies introduced for phi-spills - */ -static void remove_copies(spill_env_t *env) { - int i; - - for(i = 0; i < ARR_LEN(env->copies); ++i) { - ir_node *node = env->copies[i]; - ir_node *src; - const ir_edge_t *edge, *ne; - - assert(be_is_Copy(node)); - - src = be_get_Copy_op(node); - foreach_out_edge_safe(node, edge, ne) { - ir_node *user = get_edge_src_irn(edge); - int user_pos = get_edge_src_pos(edge); - - set_irn_n(user, user_pos, src); - } - } - - ARR_SETLEN(ir_node*, env->copies, 0); -} - -static INLINE ir_node *skip_projs(ir_node *node) { - while(is_Proj(node)) { - node = sched_next(node); - assert(!sched_is_end(node)); - } - - return node; -} - -/** - * Searchs the schedule backwards until we reach the first use or def of a - * value or a phi. - * Returns the node after this node (so that you can do sched_add_before) - */ -static ir_node *find_last_use_def(spill_env_t *env, ir_node *block, ir_node *value) { - ir_node *node, *last; + for (int i = 0; i < arity; ++i) { + ir_node *op = get_irn_n(node, i); + const arch_register_req_t *req = arch_get_irn_register_req_in(node, i); + const arch_register_t *reg; + ir_node *copy; - last = NULL; - sched_foreach_reverse(block, node) { - int i, arity; - - if(is_Phi(node)) { - return last; - } - if(value == node) { - return skip_projs(last); - } - for(i = 0, arity = get_irn_arity(node); i < arity; ++i) { - ir_node *arg = get_irn_n(node, i); - if(arg == value) { - return skip_projs(last); - } - } - last = node; - } - - // simply return first node if no def or use found - return sched_first(block); -} + if (req->cls != cls) + continue; + reg = arch_get_irn_register(op); + if (reg == NULL) + continue; -/** - * If the first usage of a Phi result would be out of memory - * there is no sense in allocating a register for it. - * Thus we spill it and all its operands to the same spill slot. - * Therefore the phi/dataB becomes a phi/Memory - * - * @param senv the spill environment - * @param phi the Phi node that should be spilled - * @param ctx_irn an user of the spilled node - * - * @return a be_Spill node - */ -static ir_node *spill_phi(spill_env_t *senv, ir_node *phi, ir_node *ctx_irn, set *already_visited_phis, bitset_t *bs) { - int i; - int arity = get_irn_arity(phi); - ir_graph *irg = senv->chordal_env->irg; - ir_node *bl = get_nodes_block(phi); - ir_node **ins, *phi_spill; - phi_spill_assoc_t key; - spill_ctx_t *ctx; - - assert(is_Phi(phi)); - DBG((senv->dbg, LEVEL_1, "%+F in ctx %+F\n", phi, ctx_irn)); - - /* build a new PhiM */ - NEW_ARR_A(ir_node *, ins, arity); - for (i = 0; i < arity; ++i) { - ins[i] = new_r_Bad(irg); - } - phi_spill = new_r_Phi(senv->chordal_env->irg, bl, arity, ins, mode_M); - key.phi = phi; - key.spill = phi_spill; - set_insert(already_visited_phis, &key, sizeof(key), HASH_PTR(phi)); - bitset_set(bs, get_irn_idx(phi)); - - /* search an existing spill for this context */ - ctx = be_get_spill_ctx(senv->spill_ctxs, phi, ctx_irn); - - /* if not found spill the phi */ - if (! ctx->spill) { - /* collect all arguments of the phi */ - for (i = 0; i < arity; ++i) { - ir_node *arg = get_irn_n(phi, i); - ir_node *sub_res; - phi_spill_assoc_t *entry; - - if(is_Phi(arg) && pset_find_ptr(senv->mem_phis, arg)) { - // looping edge? - if(arg == phi) { - sub_res = phi_spill; - } else if (! bitset_is_set(bs, get_irn_idx(arg))) { - sub_res = spill_phi(senv, arg, ctx_irn, already_visited_phis, bs); - } else { - /* we already visited the argument phi: get it's spill */ - key.phi = arg; - key.spill = NULL; - entry = set_find(already_visited_phis, &key, sizeof(key), HASH_PTR(arg)); - assert(entry && "argument phi already visited, but no spill found?!?"); - sub_res = entry->spill; - assert(sub_res && "spill missing?!?"); - } - } else { - sub_res = be_spill_irn(senv, arg, ctx_irn); - } - - set_irn_n(phi_spill, i, sub_res); - } + /* Precolored with an ignore register (which is not virtual). */ + if (reg->type & arch_register_type_virtual || + rbitset_is_set(birg->allocatable_regs, reg->global_index)) + continue; - ctx->spill = phi_spill; - } - return ctx->spill; -} + if (!arch_register_req_is(req, limited)) + continue; + if (rbitset_is_set(req->limited, reg->index)) + continue; -/** - * Spill a node. - * - * @param senv the spill environment - * @param to_spill the node that should be spilled - * - * @return a be_Spill node - */ -static ir_node *be_spill_node(spill_env_t *senv, ir_node *to_spill) { - ir_graph *irg = get_irn_irg(to_spill); - ir_node *res; - - if (pset_find_ptr(senv->mem_phis, to_spill)) { - set *already_visited_phis = new_set(cmp_phi_spill_assoc, 10); - bitset_t *bs = bitset_alloca(get_irg_last_idx(irg)); - res = spill_phi(senv, to_spill, to_spill, already_visited_phis, bs); - del_set(already_visited_phis); - } else { - res = be_spill_irn(senv, to_spill, to_spill); + copy = be_new_Copy(block, op); + stat_ev_int("constr_copy", 1); + sched_add_before(node, copy); + set_irn_n(node, i, copy); + DBG((dbg, LEVEL_3, "inserting ignore arg copy %+F for %+F pos %d\n", + copy, node, i)); } - return res; -} - -#ifdef BUGGY_REMAT - -/** - * Check if a spilled node could be rematerialized. - * - * @param senv the spill environment - * @param spill the Spill node - * @param spilled the node that was spilled - * @param reloader a irn that requires a reload - */ -static int check_remat_conditions(spill_env_t *senv, ir_node *spilled, ir_node *reloader) { - int pos, max; - - /* check for 'normal' spill and general remat condition */ - if (!arch_irn_is(senv->chordal_env->birg->main_env->arch_env, spilled, rematerializable)) - return 0; - - /* check availability of original arguments */ - if (is_Block(reloader)) { + /* insert copies for nodes that occur constrained more than once. */ + be_foreach_use(node, cls, req, in, in_req_, + if (!arch_register_req_is(req, limited)) + continue; - /* we want to remat at the end of a block. - * thus all arguments must be alive at the end of the block - */ - for (pos=0, max=get_irn_arity(spilled); poscls != cls) + continue; + if (!arch_register_req_is(req2, limited)) + continue; + + in2 = get_irn_n(node, i2); + if (in2 != in) + continue; + + /* if the constraint is the same, no copy is necessary + * TODO generalise unequal but overlapping constraints */ + if (rbitsets_equal(req->limited, req2->limited, cls->n_regs)) + continue; + + ir_node *copy = be_new_Copy(block, in); + stat_ev_int("constr_copy", 1); + + sched_add_before(node, copy); + set_irn_n(node, i2, copy); + DBG((dbg, LEVEL_3, + "inserting multiple constr copy %+F for %+F pos %d\n", + copy, node, i2)); } + ); - } else { - - /* we want to remat before the insn reloader - * thus an arguments is alive if - * - it interferes with the reloaders result - * or - * - or it is (last-) used by reloader itself - */ - for (pos=0, max=get_irn_arity(spilled); posn_regs); } + rbitset_or(def_constr, req->limited, cls->n_regs); + ); + /* no output constraints => we're good */ + if (def_constr == NULL) { + return; } - return 1; -} - -#else /* BUGGY_REMAT */ - -/** - * A very simple rematerialization checker. - * - * @param senv the spill environment - * @param spill the Spill node - * @param spilled the node that was spilled - * @param reloader a irn that requires a reload - */ -static int check_remat_conditions(spill_env_t *senv, ir_node *spilled, ir_node *reloader) { - const arch_env_t *aenv = senv->chordal_env->birg->main_env->arch_env; - - return get_irn_arity(spilled) == 0 && - arch_irn_is(aenv, spilled, rematerializable); -} - -#endif /* BUGGY_REMAT */ - -/** - * Re-materialize a node. - * - * @param senv the spill environment - * @param spilled the node that was spilled - * @param reloader a irn that requires a reload - */ -static ir_node *do_remat(spill_env_t *senv, ir_node *spilled, ir_node *reloader) { - ir_node *res; - ir_node *bl = (is_Block(reloader)) ? reloader : get_nodes_block(reloader); - - /* recompute the value */ - res = new_ir_node(get_irn_dbg_info(spilled), senv->chordal_env->irg, bl, - get_irn_op(spilled), - get_irn_mode(spilled), - get_irn_arity(spilled), - get_irn_in(spilled) + 1); - copy_node_attr(spilled, res); - - DBG((senv->dbg, LEVEL_1, "Insert remat %+F before reloader %+F\n", res, reloader)); - - /* insert in schedule */ - if (is_Block(reloader)) { - ir_node *insert = sched_skip(reloader, 0, sched_skip_cf_predicator, (void *) senv->chordal_env->birg->main_env->arch_env); - sched_add_after(insert, res); - } else { - sched_add_before(reloader, res); - } - - return res; -} - -static void place_copies_for_phi(spill_env_t *env, ir_node* node) { - int i, arity; - - assert(is_Phi(node)); - - /* We have to place copy nodes in the predecessor blocks to temporarily - * produce new values that get separate spill slots + /* + * insert copies for all constrained arguments living through the node + * and being constrained to a register which also occurs in out constraints. */ - for(i = 0, arity = get_irn_arity(node); i < arity; ++i) { - ir_node *pred_block, *arg, *copy, *insert_point; - - /* Don't do anything for looping edges (there's no need - * and placing copies here breaks stuff as it suddenly - * generates new living values through the whole loop) + unsigned *const tmp = rbitset_alloca(cls->n_regs); + be_foreach_use(node, cls, req, in, in_req_, + /* Check, if + * 1) the operand is constrained. + * 2) lives through the node. + * 3) is constrained to a register occurring in out constraints. */ - arg = get_irn_n(node, i); - if(arg == node) + if (!arch_register_req_is(req, limited)) + continue; + if (!be_values_interfere(lv, node, in)) continue; - pred_block = get_Block_cfgpred_block(get_nodes_block(node), i); - copy = be_new_Copy(env->cls, get_irn_irg(arg), pred_block, arg); - - ARR_APP1(ir_node*, env->copies, copy); - insert_point = find_last_use_def(env, pred_block, arg); - sched_add_before(insert_point, copy); - - set_irn_n(node, i, copy); - } -} - -void be_place_copies(spill_env_t *env) { - ir_node *node; - - foreach_pset(env->mem_phis, node) { - place_copies_for_phi(env, node); - } -} - -void be_spill_phi(spill_env_t *env, ir_node *node) { - spill_ctx_t *spill_ctx; - - assert(is_Phi(node)); - - pset_insert_ptr(env->mem_phis, node); - - // remove spill context for this phi (if there was one) - spill_ctx = be_get_spill_ctx(env->spill_ctxs, node, node); - if(spill_ctx != NULL) { - spill_ctx->spill = NULL; - } -} - -void be_insert_spills_reloads(spill_env_t *env) { - const arch_env_t *arch_env = env->chordal_env->birg->main_env->arch_env; - //ir_node *node; - spill_info_t *si; - -#if 0 - // Matze: This should be pointless as beladies fix_block_borders - // should result in the same - DBG((env->dbg, LEVEL_1, "Reloads for mem-phis:\n")); - foreach_pset(env->mem_phis, node) { - const ir_edge_t *e; - - assert(is_Phi(node)); - - /* Add reloads for mem_phis */ - /* BETTER: These reloads (1) should only be inserted, if they are really needed */ - DBG((env->dbg, LEVEL_1, " Mem-phi %+F\n", node)); - foreach_out_edge(node, e) { - ir_node *user = e->src; - if (is_Phi(user) && !pset_find_ptr(env->mem_phis, user)) { - ir_node *use_bl = get_nodes_block(user); - DBG((env->dbg, LEVEL_1, " non-mem-phi user %+F\n", user)); - be_add_reload_on_edge(env, node, use_bl, e->pos); /* (1) */ - } - } - } -#endif - - /* process each spilled node */ - DBG((env->dbg, LEVEL_1, "Insert spills and reloads:\n")); - for(si = set_first(env->spills); si; si = set_next(env->spills)) { - reloader_t *rld; - ir_mode *mode = get_irn_mode(si->spilled_node); - pset *values = pset_new_ptr(16); - - /* go through all reloads for this spill */ - for(rld = si->reloaders; rld; rld = rld->next) { - ir_node *new_val; - - if (check_remat_conditions(env, si->spilled_node, rld->reloader)) { - new_val = do_remat(env, si->spilled_node, rld->reloader); - } else { - /* the spill for this reloader */ - ir_node *spill = be_spill_node(env, si->spilled_node); - - /* do a reload */ - new_val = be_reload(arch_env, env->cls, rld->reloader, mode, spill); - } - - DBG((env->dbg, LEVEL_1, " %+F of %+F before %+F\n", new_val, si->spilled_node, rld->reloader)); - pset_insert_ptr(values, new_val); - } - - /* introduce copies, rewire the uses */ - assert(pset_count(values) > 0 && "???"); - pset_insert_ptr(values, si->spilled_node); - be_ssa_constr_set_ignore(env->chordal_env->dom_front, env->chordal_env->lv, values, env->mem_phis); - - del_pset(values); - } - - remove_copies(env); - - // reloads are placed now, but we might reuse the spill environment for further spilling decisions - del_set(env->spills); - env->spills = new_set(cmp_spillinfo, 1024); -} - -void be_add_reload(spill_env_t *env, ir_node *to_spill, ir_node *before) { - spill_info_t templ, *res; - reloader_t *rel; - - assert(sched_is_scheduled(before)); - assert(arch_irn_consider_in_reg_alloc(env->chordal_env->birg->main_env->arch_env, env->cls, to_spill)); + rbitset_copy(tmp, req->limited, cls->n_regs); + rbitset_and(tmp, def_constr, cls->n_regs); - templ.spilled_node = to_spill; - templ.reloaders = NULL; - res = set_insert(env->spills, &templ, sizeof(templ), HASH_PTR(to_spill)); + if (rbitset_is_empty(tmp, cls->n_regs)) + continue; - rel = obstack_alloc(&env->obst, sizeof(rel[0])); - rel->reloader = before; - rel->next = res->reloaders; - res->reloaders = rel; + /* + * only create the copy if the operand is no copy. + * this is necessary since the assure constraints phase inserts + * Copies and Keeps for operands which must be different from the + * results. Additional copies here would destroy this. + */ + if (be_is_Copy(in)) + continue; - be_liveness_add_missing(env->chordal_env->lv); + ir_node *copy = be_new_Copy(block, in); + sched_add_before(node, copy); + set_irn_n(node, i_, copy); + DBG((dbg, LEVEL_3, "inserting constr copy %+F for %+F pos %d\n", + copy, node, i_)); + be_liveness_update(lv, in); + ); } -void be_add_reload_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos) { - ir_node *predblock, *last; - - /* simply add the reload to the beginning of the block if we only have 1 predecessor - * (we don't need to check for phis as there can't be any in a block with only 1 pred) - */ - if(get_Block_n_cfgpreds(block) == 1) { - assert(!is_Phi(sched_first(block))); - be_add_reload(env, to_spill, sched_first(block)); - return; - } - - /* We have to reload the value in pred-block */ - predblock = get_Block_cfgpred_block(block, pos); - last = sched_last(predblock); - - /* we might have projs and keepanys behind the jump... */ - while(is_Proj(last) || be_is_Keep(last)) { - last = sched_prev(last); - assert(!sched_is_end(last)); +static void pre_spill_prepare_constr_walker(ir_node *block, void *data) +{ + be_pre_spill_env_t *env = (be_pre_spill_env_t*)data; + sched_foreach(block, node) { + prepare_constr_insn(env, node); } - assert(is_cfop(last)); - - // add the reload before the (cond-)jump - be_add_reload(env, to_spill, last); } -/**************************************** - - SPILL SLOT MANAGEMENT AND OPTS - -****************************************/ - -typedef struct _spill_slot_t { - unsigned size; - unsigned align; - pset *members; - ir_mode *largest_mode; /* the mode of all members with largest size */ -} spill_slot_t; - -typedef struct _ss_env_t { - struct obstack ob; - be_chordal_env_t *cenv; - pmap *slots; /* maps spill_contexts to spill_slots */ - pmap *types; /* maps modes to types */ - DEBUG_ONLY(firm_dbg_module_t *dbg;) -} ss_env_t; - +void be_pre_spill_prepare_constr(ir_graph *irg, + const arch_register_class_t *cls) +{ + be_pre_spill_env_t env; + memset(&env, 0, sizeof(env)); + env.irg = irg; + env.cls = cls; -/** - * Walker: compute the spill slots - */ -static void compute_spill_slots_walker(ir_node *spill, void *env) { - ss_env_t *ssenv = env; - arch_env_t *arch_env = ssenv->cenv->birg->main_env->arch_env; - ir_node *ctx; - pmap_entry *entry; - spill_slot_t *ss; - const arch_register_class_t *cls; + be_assure_live_sets(irg); - if (! be_is_Spill(spill)) - return; - - cls = arch_get_irn_reg_class(arch_env, spill, be_pos_Spill_val); - - if (cls != ssenv->cenv->cls) - return; - - /* check, if this spill is for a context already known */ - ctx = be_get_Spill_context(spill); - entry = pmap_find(ssenv->slots, ctx); - - if (! entry) { - ir_mode *largest_mode = arch_register_class_mode(cls); - - /* this is a new spill context */ - ss = obstack_alloc(&ssenv->ob, sizeof(*ss)); - ss->members = pset_new_ptr(8); - ss->largest_mode = largest_mode; - ss->size = get_mode_size_bytes(ss->largest_mode); - ss->align = arch_isa_get_reg_class_alignment(arch_env->isa, cls); - pmap_insert(ssenv->slots, ctx, ss); - } else { - /* values with the same spill_ctx must go into the same spill slot */ - ss = entry->value; - -#ifndef NDEBUG - /* ugly mega assert :-) */ - { - ir_node *irn; - struct _arch_env_t *arch_env = ssenv->cenv->birg->main_env->arch_env; - const arch_register_class_t *cls = arch_get_irn_reg_class(arch_env, spill, be_pos_Spill_val); - int size = get_mode_size_bytes(arch_register_class_mode(cls)); - assert((int) ss->size == size && "Different sizes for the same spill slot are not allowed."); - for (irn = pset_first(ss->members); irn; irn = pset_next(ss->members)) { - /* use values_interfere here, because it uses the dominance check, - which does work for values in memory */ - assert(!values_interfere(ssenv->cenv->lv, spill, irn) && "Spills for the same spill slot must not interfere!"); - } - } -#endif /* NDEBUG */ - } - - pset_insert_ptr(ss->members, spill); -} - -/** - * qsort compare function, sort spill slots by size. - */ -static int ss_sorter(const void *v1, const void *v2) { - const spill_slot_t **ss1 = (const spill_slot_t **)v1; - const spill_slot_t **ss2 = (const spill_slot_t **)v2; - return ((int) (*ss2)->size) - ((int) (*ss1)->size); + irg_block_walk_graph(irg, pre_spill_prepare_constr_walker, NULL, &env); } -/** - * This function should optimize the spill slots. - * - Coalescing of multiple slots - * - Ordering the slots - * - * Input slots are in @p ssenv->slots - * @p size The count of initial spill slots in @p ssenv->slots - * This also is the size of the preallocated array @p ass - * - * @return An array of spill slots @p ass in specific order - **/ -static void optimize_slots(ss_env_t *ssenv, int size, spill_slot_t *ass[]) { - int i, o, used_slots; - pmap_entry *entr; - - i=0; - pmap_foreach(ssenv->slots, entr) - ass[i++] = entr->value; - - /* Sort the array to minimize fragmentation and cache footprint. - Large slots come first */ - qsort(ass, size, sizeof(ass[0]), ss_sorter); - - /* For each spill slot: - - assign a new offset to this slot - - xor find another slot to coalesce with */ - used_slots = 0; - for (i=0; idbg, LEVEL_1, "Spill slot %d members:\n", i)); - for(n1 = pset_first(ass[i]->members); n1; n1 = pset_next(ass[i]->members)) - DBG((ssenv->dbg, LEVEL_1, " %+F\n", n1)); - - - for (o=0; o < used_slots && tgt_slot == -1; ++o) { /* for each offset-assigned spill slot */ - /* check inter-slot-pairs for interference */ - ir_node *n2; - for(n1 = pset_first(ass[i]->members); n1; n1 = pset_next(ass[i]->members)) - for(n2 = pset_first(ass[o]->members); n2; n2 = pset_next(ass[o]->members)) - if(values_interfere(ssenv->cenv->lv, n1, n2)) { - pset_break(ass[i]->members); - pset_break(ass[o]->members); - DBG((ssenv->dbg, LEVEL_1, " Interf %+F -- %+F\n", n1, n2)); - goto interf_detected; - } - - /* if we are here, there is no interference between ass[i] and ass[o] */ - tgt_slot = o; - -interf_detected: /*nothing*/ ; - } - /* now the members of ass[i] join the members of ass[tgt_slot] */ +int be_coalesce_spill_slots = 1; +int be_do_remats = 1; - /* do we need a new slot? */ - if (tgt_slot == -1) { - tgt_slot = used_slots; - used_slots++; +static const lc_opt_table_entry_t be_spill_options[] = { + LC_OPT_ENT_BOOL ("coalesce_slots", "coalesce the spill slots", &be_coalesce_spill_slots), + LC_OPT_ENT_BOOL ("remat", "try to rematerialize values instead of reloading", &be_do_remats), + LC_OPT_LAST +}; - /* init slot */ - if (tgt_slot != i) { - ass[tgt_slot]->size = ass[i]->size; - del_pset(ass[tgt_slot]->members); - ass[tgt_slot]->members = pset_new_ptr(8); - } - } +static be_module_list_entry_t *spillers = NULL; +static const be_spiller_t *selected_spiller = NULL; - /* copy the members to the target pset */ - /* NOTE: If src and tgt pset are the same, inserting while iterating is not allowed */ - if (tgt_slot != i) - for(n1 = pset_first(ass[i]->members); n1; n1 = pset_next(ass[i]->members)) - pset_insert_ptr(ass[tgt_slot]->members, n1); - } +void be_register_spiller(const char *name, be_spiller_t *spiller) +{ + if (selected_spiller == NULL) + selected_spiller = spiller; + be_add_module_to_list(&spillers, name, spiller); } -#define ALIGN_SPILL_AREA 16 -#define pset_foreach(pset, elm) for(elm=pset_first(pset); elm; elm=pset_next(pset)) +void be_do_spill(ir_graph *irg, const arch_register_class_t *cls) +{ + assert(selected_spiller != NULL); -/** - * Returns a spill type for a mode. Keep them in a map to reduce - * the number of types. - * - * @param types a map containing all created types - * @param ss the spill slot - * - * Note that type types should are identical for every mode. - * This rule might break if two different register classes return the same - * mode but different alignments. - */ -static ir_type *get_spill_type(pmap *types, spill_slot_t *ss) { - pmap_entry *e = pmap_find(types, ss->largest_mode); - ir_type *res; - - if (! e) { - char buf[64]; - snprintf(buf, sizeof(buf), "spill_slot_type_%s", get_mode_name(ss->largest_mode)); - buf[sizeof(buf) - 1] = '\0'; - res = new_type_primitive(new_id_from_str(buf), ss->largest_mode); - set_type_alignment_bytes(res, ss->align); - pmap_insert(types, ss->largest_mode, res); - } else { - res = e->value; - assert(get_type_alignment_bytes(res) == (int)ss->align); - } - - return res; + selected_spiller->spill(irg, cls); } -/** - * Create spill slot entities on the frame type. - * - * @param ssenv the spill environment - * @param n number of spill slots - * @param ss array of spill slots - */ -static void assign_entities(ss_env_t *ssenv, int n_slots, spill_slot_t *ss[]) { - int i, offset, frame_align; - ir_type *frame; +BE_REGISTER_MODULE_CONSTRUCTOR(be_init_spilloptions) +void be_init_spilloptions(void) +{ + lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be"); + lc_opt_entry_t *spill_grp = lc_opt_get_grp(be_grp, "spill"); - /* do not align the frame if no spill slots are needed */ - if (n_slots <= 0) - return; - - frame = get_irg_frame_type(ssenv->cenv->irg); - - /* aligning by increasing frame size */ - offset = get_type_size_bytes(frame); - offset = round_up2(offset, ALIGN_SPILL_AREA); - - /* create entities and assign offsets according to size and alignment*/ - for (i = 0; i < n_slots; ++i) { - char buf[64]; - ident *name; - entity *spill_ent; - ir_node *irn; - - /* build entity */ - snprintf(buf, sizeof(buf), "spill_slot_%d", i); - buf[sizeof(buf) - 1] = '\0'; - name = new_id_from_str(buf); - - spill_ent = new_entity(frame, name, get_spill_type(ssenv->types, ss[i])); - - /* align */ - offset = round_up2(offset, ss[i]->align); - /* set */ - set_entity_offset_bytes(spill_ent, offset); - /* next possible offset */ - offset += round_up2(ss[i]->size, ss[i]->align); - - pset_foreach(ss[i]->members, irn) - be_set_Spill_entity(irn, spill_ent); - } - - - /* set final size of stack frame */ - frame_align = get_type_alignment_bytes(frame); - set_type_size_bytes(frame, round_up2(offset, frame_align)); -} + lc_opt_add_table(spill_grp, be_spill_options); + be_add_module_list_opt(be_grp, "spiller", "spill algorithm", + &spillers, (void**) &selected_spiller); -void be_compute_spill_offsets(be_chordal_env_t *cenv) { - ss_env_t ssenv; - spill_slot_t **ss; - int ss_size; - pmap_entry *pme; - - obstack_init(&ssenv.ob); - ssenv.cenv = cenv; - ssenv.slots = pmap_create(); - ssenv.types = pmap_create(); - FIRM_DBG_REGISTER(ssenv.dbg, "firm.be.spillslots"); - - /* Get initial spill slots */ - irg_walk_graph(cenv->irg, NULL, compute_spill_slots_walker, &ssenv); - - /* Build an empty array for optimized spill slots */ - ss_size = pmap_count(ssenv.slots); - ss = obstack_alloc(&ssenv.ob, ss_size * sizeof(*ss)); - optimize_slots(&ssenv, ss_size, ss); - - /* Integrate slots into the stack frame entity */ - assign_entities(&ssenv, ss_size, ss); - - /* Clean up */ - pmap_foreach(ssenv.slots, pme) - del_pset(((spill_slot_t *)pme->value)->members); - pmap_destroy(ssenv.slots); - pmap_destroy(ssenv.types); - obstack_free(&ssenv.ob, NULL); - - be_copy_entities_to_reloads(cenv->irg); + FIRM_DBG_REGISTER(dbg, "firm.be.spillprepare"); }