X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbespillbelady.c;h=c5e58b727dc4f628439b472e7fd9eed32e22ba14;hb=205396c4f4f5abe7abd6dc2350c8c398a7623afc;hp=dcc58684740b0e9988af0898f4c2ebafc20405b8;hpb=02046d6f22e734521c84dfb2f342cf61e6442c2f;p=libfirm diff --git a/ir/be/bespillbelady.c b/ir/be/bespillbelady.c index dcc586847..c5e58b727 100644 --- a/ir/be/bespillbelady.c +++ b/ir/be/bespillbelady.c @@ -9,14 +9,6 @@ #include "config.h" #endif -#ifdef HAVE_ALLOCA_H -#include -#endif - -#ifdef HAVE_MALLOC_H -#include -#endif - #include "obst.h" #include "set.h" #include "pset.h" @@ -29,9 +21,10 @@ #include "iredges_t.h" #include "ircons_t.h" #include "irprintf.h" +#include "xmalloc.h" #include "beutil.h" -#include "bearch.h" +#include "bearch_t.h" #include "bespillbelady.h" #include "beuses_t.h" #include "besched_t.h" @@ -40,6 +33,7 @@ #include "benode_t.h" #include "bechordal_t.h" #include "bespilloptions.h" +#include "beloopana.h" #define DBG_SPILL 1 #define DBG_WSETS 2 @@ -69,6 +63,7 @@ typedef struct _belady_env_t { const arch_env_t *arch; const arch_register_class_t *cls; const be_lv_t *lv; + be_loopana_t *loop_ana; int n_regs; /** number of regs in this reg-class */ workset_t *ws; /**< the main workset used while processing a block. ob-allocated */ @@ -87,7 +82,7 @@ static int loc_compare(const void *a, const void *b) return p->time - q->time; } -void workset_print(const workset_t *w) +static INLINE void workset_print(const workset_t *w) { int i; @@ -246,48 +241,6 @@ static INLINE unsigned get_distance(belady_env_t *env, ir_node *from, unsigned f return use.time; } -#if 0 -/** - * Fix to remove dead nodes (especially don't spill nodes) from workset. - */ -static void fix_dead_values(workset_t *ws, ir_node *irn) { - int idx; - ir_node *node; - ir_node *block = get_nodes_block(irn); - - DBG((dbg, DBG_DECIDE, "fixing dead values at %+F:\n", irn)); - - workset_foreach(ws, node, idx) { - const ir_edge_t *edge; - int fixme = 1; - - /* skip already fixed nodes */ - if (workset_get_time(ws, idx) == INT_MAX) - continue; - - /* check all users */ - foreach_out_edge(node, edge) { - ir_node *user = get_edge_src_irn(edge); - - if ((get_nodes_block(user) != block) || /* user is in a different block */ - (sched_is_scheduled(user) && sched_comes_after(irn, user)) || /* user is scheduled after irn */ - user == irn) /* irn is the user */ - { /* => don't fix distance */ - fixme = 0; - break; - } - } - - /* all users scheduled prior to current irn in in same block as irn -> fix */ - if (fixme) { - workset_set_time(ws, idx, INT_MAX); - DBG((dbg, DBG_DECIDE, "\tfixing time for %+F to INT_MAX\n", node)); - } - } - -} -#endif - /** * Performs the actions necessary to grant the request that: * - new_vals can be held in registers @@ -344,19 +297,6 @@ static void displace(belady_env_t *env, workset_t *new_vals, int is_usage) { workset_set_time(ws, i, dist); } -#if 0 - /* - FIX for don't spill nodes: - Problem is that get_distance always returns 0 for those nodes even if they are not - needed anymore (all their usages have already been visited). - Even if we change this behavior, get_distance doesn't distinguish between not - used anymore (dead) and live out of block. - Solution: Set distances of all nodes having all their usages in schedule prior to - current instruction to MAX_INT. - */ - fix_dead_values(ws, env->instr); -#endif - /* sort entries by increasing nextuse-distance*/ workset_sort(ws); @@ -395,18 +335,28 @@ static void displace(belady_env_t *env, workset_t *new_vals, int is_usage) { static void belady(ir_node *block, void *env); -static loc_t to_take_or_not_to_take(belady_env_t *env, ir_node* first, ir_node *node, ir_node *block, ir_loop *loop) { +/** Decides whether a specific node should be in the start workset or not + * + * @param env belady environment + * @param first + * @param node the node to test + * @param block the block of the node + * @param loop the loop of the node + */ +static loc_t to_take_or_not_to_take(belady_env_t *env, ir_node* first, + ir_node *node, ir_node *block, + ir_loop *loop) +{ be_next_use_t next_use; loc_t loc; loc.time = USES_INFINITY; + loc.irn = node; if (!arch_irn_consider_in_reg_alloc(env->arch, env->cls, node)) { loc.time = USES_INFINITY; return loc; } - loc.irn = node; - /* We have to keep nonspillable nodes in the workingset */ if(arch_irn_get_flags(env->arch, node) & arch_irn_flags_dont_spill) { loc.time = 0; @@ -417,9 +367,12 @@ static loc_t to_take_or_not_to_take(belady_env_t *env, ir_node* first, ir_node * next_use = be_get_next_use(env->uses, first, 0, node, 0); if(USES_IS_INFINITE(next_use.time)) { // the nodes marked as live in shouldn't be dead, so it must be a phi + assert(is_Phi(node)); loc.time = USES_INFINITY; DBG((dbg, DBG_START, " %+F not taken (dead)\n", node)); - assert(is_Phi(node)); + if(is_Phi(node)) { + be_spill_phi(env->senv, node); + } return loc; } @@ -427,13 +380,11 @@ static loc_t to_take_or_not_to_take(belady_env_t *env, ir_node* first, ir_node * if(next_use.outermost_loop >= get_loop_depth(loop)) { DBG((dbg, DBG_START, " %+F taken (%u, loop %d)\n", node, loc.time, next_use.outermost_loop)); - return loc; - // ARR_APP1(loc_t, starters, loc); } else { - loc.time = USES_INFINITY; - DBG((dbg, DBG_START, " %+F not taken (outerloopdepth %d < loopdetph %d)\n", node, next_use.outermost_loop, get_loop_depth(loop))); - return loc; + loc.time = USES_PENDING; + DBG((dbg, DBG_START, " %+F delayed (outerloopdepth %d < loopdetph %d)\n", node, next_use.outermost_loop, get_loop_depth(loop))); } + return loc; } /* @@ -441,15 +392,17 @@ static loc_t to_take_or_not_to_take(belady_env_t *env, ir_node* first, ir_node * * and notifies spill algorithm which phis need to be spilled */ static void compute_live_ins(ir_node *block, void *data) { - belady_env_t *env = data; - block_info_t *block_info; - ir_node *first, *irn; - loc_t loc, *starters; - int i, len, ws_count; - ir_loop *loop = get_irn_loop(block); - const be_lv_t *lv = env->lv; - - if(get_Block_n_cfgpreds(block) == 1 && get_irg_start_block(get_irn_irg(block)) != block) + belady_env_t *env = data; + ir_loop *loop = get_irn_loop(block); + const be_lv_t *lv = env->lv; + block_info_t *block_info; + ir_node *first, *irn; + loc_t loc, *starters, *delayed; + int i, len, ws_count; + int free_slots, free_pressure_slots; + unsigned pressure; + + if (get_Block_n_cfgpreds(block) == 1 && get_irg_start_block(get_irn_irg(block)) != block) return; block_info = new_block_info(&env->ob); @@ -457,42 +410,67 @@ static void compute_live_ins(ir_node *block, void *data) { /* Collect all values living at start of block */ starters = NEW_ARR_F(loc_t, 0); - - /* rebuild schedule time information, because it seems to be broken */ - // Matze: is this still true? - //sched_renumber(block); + delayed = NEW_ARR_F(loc_t, 0); DBG((dbg, DBG_START, "Living at start of %+F:\n", block)); first = sched_first(block); + /* check all Phis first */ sched_foreach(block, irn) { - if(!is_Phi(irn)) + if (! is_Phi(irn)) break; loc = to_take_or_not_to_take(env, first, irn, block, loop); - if(!USES_IS_INFINITE(loc.time)) { - ARR_APP1(loc_t, starters, loc); - } else { - be_spill_phi(env->senv, irn); + if (! USES_IS_INFINITE(loc.time)) { + if (USES_IS_PENDING(loc.time)) + ARR_APP1(loc_t, delayed, loc); + else + ARR_APP1(loc_t, starters, loc); } } + /* check all Live-Ins */ be_lv_foreach(lv, block, be_lv_state_in, i) { ir_node *node = be_lv_get_irn(lv, block, i); loc = to_take_or_not_to_take(env, first, node, block, loop); - if(!USES_IS_INFINITE(loc.time)) { - ARR_APP1(loc_t, starters, loc); + if (! USES_IS_INFINITE(loc.time)) { + if (USES_IS_PENDING(loc.time)) + ARR_APP1(loc_t, delayed, loc); + else + ARR_APP1(loc_t, starters, loc); } } - // Sort start values by first use + pressure = be_get_loop_pressure(env->loop_ana, env->cls, loop); + assert(ARR_LEN(delayed) <= pressure); + free_slots = env->n_regs - ARR_LEN(starters); + free_pressure_slots = env->n_regs - (pressure - ARR_LEN(delayed)); + free_slots = MIN(free_slots, free_pressure_slots); + /* append nodes delayed due to loop structure until start set is full */ + for (i = 0; i < ARR_LEN(delayed) && i < free_slots; ++i) { + DBG((dbg, DBG_START, " delayed %+F taken\n", delayed[i].irn)); + ARR_APP1(loc_t, starters, delayed[i]); + delayed[i].irn = NULL; + } + + /* spill all delayed phis which didn't make it into start workset */ + for (i = ARR_LEN(delayed) - 1; i >= 0; --i) { + ir_node *irn = delayed[i].irn; + if (irn && is_Phi(irn)) { + DBG((dbg, DBG_START, " spilling delayed phi %+F\n", irn)); + be_spill_phi(env->senv, irn); + } + } + DEL_ARR_F(delayed); + + /* Sort start values by first use */ qsort(starters, ARR_LEN(starters), sizeof(starters[0]), loc_compare); /* Copy the best ones from starters to start workset */ - ws_count = MIN(ARR_LEN(starters), env->n_regs); + ws_count = MIN(ARR_LEN(starters), env->n_regs); block_info->ws_start = new_workset(env, &env->ob); workset_bulk_fill(block_info->ws_start, ws_count, starters); @@ -500,7 +478,7 @@ static void compute_live_ins(ir_node *block, void *data) { len = ARR_LEN(starters); for (i = ws_count; i < len; ++i) { irn = starters[i].irn; - if (!is_Phi(irn) || get_nodes_block(irn) != block) + if (! is_Phi(irn) || get_nodes_block(irn) != block) continue; be_spill_phi(env->senv, irn); @@ -688,27 +666,44 @@ next_value: } } -void be_spill_belady(be_irg_t *birg, const arch_register_class_t *cls) { +/** + * Do spilling for a register class on a graph using the belady heuristic. + * In the transformed graph, the register pressure never exceeds the number + * of available registers. + * + * @param birg The backend graph + * @param cls The register class to spill + */ +static void be_spill_belady(be_irg_t *birg, const arch_register_class_t *cls) { be_spill_belady_spill_env(birg, cls, NULL); } void be_spill_belady_spill_env(be_irg_t *birg, const arch_register_class_t *cls, spill_env_t *spill_env) { belady_env_t env; ir_graph *irg = be_get_birg_irg(birg); + int n_regs; - FIRM_DBG_REGISTER(dbg, "firm.be.spill.belady"); - //firm_dbg_set_mask(dbg, DBG_SPILL); + /* some special classes contain only ignore regs, nothing to do then */ + n_regs = cls->n_regs - be_put_ignore_regs(birg, cls, NULL); + if(n_regs == 0) + return; + be_invalidate_liveness(birg); be_assure_liveness(birg); + /* construct control flow loop tree */ + if(! (get_irg_loopinfo_state(irg) & loopinfo_cf_consistent)) { + construct_cf_backedges(irg); + } /* init belady env */ obstack_init(&env.ob); env.arch = birg->main_env->arch_env; env.cls = cls; env.lv = be_get_birg_liveness(birg); - env.n_regs = env.cls->n_regs - be_put_ignore_regs(birg, cls, NULL); + env.n_regs = n_regs; env.ws = new_workset(&env, &env.ob); env.uses = be_begin_uses(irg, env.lv); + env.loop_ana = be_new_loop_pressure(birg); if(spill_env == NULL) { env.senv = be_new_spill_env(birg); } else { @@ -730,21 +725,18 @@ void be_spill_belady_spill_env(be_irg_t *birg, const arch_register_class_t *cls, if(spill_env == NULL) be_delete_spill_env(env.senv); be_end_uses(env.uses); + be_free_loop_pressure(env.loop_ana); obstack_free(&env.ob, NULL); } -static void be_spill_belady_oldinterface(const be_chordal_env_t *chordal_env) -{ - be_spill_belady(chordal_env->birg, chordal_env->cls); -} - void be_init_spillbelady(void) { static be_spiller_t belady_spiller = { - be_spill_belady_oldinterface + be_spill_belady }; be_register_spiller("belady", &belady_spiller); + FIRM_DBG_REGISTER(dbg, "firm.be.spill.belady"); } BE_REGISTER_MODULE_CONSTRUCTOR(be_init_spillbelady);