From: Christian Würdig Date: Wed, 21 Feb 2007 17:18:42 +0000 (+0000) Subject: check register pressure in loops for variables, selected for spilling due to loop... X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=1a684155e6dadb818cb3afebe4ae80e2c33a2a48;p=libfirm check register pressure in loops for variables, selected for spilling due to loop structure --- diff --git a/ir/be/bespillbelady.c b/ir/be/bespillbelady.c index 8710ccc99..dac32ee8d 100644 --- a/ir/be/bespillbelady.c +++ b/ir/be/bespillbelady.c @@ -40,6 +40,7 @@ #include "benode_t.h" #include "bechordal_t.h" #include "bespilloptions.h" +#include "beloopana.h" #define DBG_SPILL 1 #define DBG_WSETS 2 @@ -69,6 +70,7 @@ 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 */ @@ -372,13 +374,11 @@ 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; } /* @@ -386,15 +386,17 @@ 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); @@ -402,38 +404,58 @@ 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); + 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); + 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); } else { be_spill_phi(env->senv, irn); } } + /* 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); + free_slots = env->n_regs - ARR_LEN(starters); + free_pressure_slots = env->n_regs - pressure; + 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]); + } + 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); @@ -441,7 +463,7 @@ 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); @@ -654,6 +676,7 @@ void be_spill_belady_spill_env(be_irg_t *birg, const arch_register_class_t *cls, env.n_regs = env.cls->n_regs - be_put_ignore_regs(birg, cls, NULL); 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 { @@ -675,6 +698,7 @@ 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); }