+++ /dev/null
-/*
- * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
- *
- * This file is part of libFirm.
- *
- * This file may be distributed and/or modified under the terms of the
- * GNU General Public License version 2 as published by the Free Software
- * Foundation and appearing in the file LICENSE.GPL included in the
- * packaging of this file.
- *
- * Licensees holding valid libFirm Professional Edition licenses may use
- * this file in accordance with the libFirm Commercial License.
- * Agreement provided with the Software.
- *
- * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
- * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE.
- */
-
-/**
- * @file
- * @brief Morgans spill algorithm.
- * @author Matthias Braun
- * @date 05.05.2006
- * @version $Id$
- */
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include "irgwalk.h"
-#include "irloop_t.h"
-#include "irgraph_t.h"
-#include "irprintf.h"
-#include "obst.h"
-#include "error.h"
-
-#include "bespillmorgan.h"
-#include "bechordal_t.h"
-#include "bespill.h"
-#include "belive_t.h"
-#include "beabi.h"
-#include "bespillbelady.h"
-#include "beverify.h"
-#include "benodesets.h"
-#include "bespilloptions.h"
-#include "besched.h"
-#include "beutil.h"
-#include "bemodule.h"
-#include "beirg_t.h"
-
-#define DBG_LIVE 1
-#define DBG_LOOPANA 2
-#define DBG_PRESSURE 4
-#define DBG_SPILLS 8
-#define DBG_CHOOSE 16
-DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
-
-typedef struct morgan_env {
- const arch_env_t *arch;
- const arch_register_class_t *cls;
- ir_graph *irg;
- be_lv_t *lv;
- struct obstack obst;
- /** maximum safe register pressure */
- int registers_available;
-
- spill_env_t *senv;
-
- set *loop_attr_set;
- set *block_attr_set;
-} morgan_env_t;
-
-typedef struct loop_edge {
- ir_node *block;
- int pos;
-} loop_edge_t;
-
-typedef struct loop_attr {
- const ir_loop *loop;
- set *out_edges;
- set *in_edges;
- /** The set of all values that are live in the loop but not used in the loop */
- bitset_t *livethrough_unused;
-} loop_attr_t;
-
-typedef struct morgan_block_attr {
- const ir_node *block;
- /** set of all values that are live in the block but not used in the block */
- bitset_t *livethrough_unused;
-} block_attr_t;
-
-//---------------------------------------------------------------------------
-
-static int loop_edge_cmp(const void* p1, const void* p2, size_t size) {
- loop_edge_t *e1 = (loop_edge_t*) p1;
- loop_edge_t *e2 = (loop_edge_t*) p2;
- (void) size;
-
- return e1->block != e2->block || e1->pos != e2->pos;
-}
-
-static int loop_attr_cmp(const void *e1, const void *e2, size_t size) {
- loop_attr_t *la1 = (loop_attr_t*) e1;
- loop_attr_t *la2 = (loop_attr_t*) e2;
- (void) size;
-
- return la1->loop != la2->loop;
-}
-
-static int block_attr_cmp(const void *e1, const void *e2, size_t size) {
- block_attr_t *b1 = (block_attr_t*) e1;
- block_attr_t *b2 = (block_attr_t*) e2;
- (void) size;
-
- return b1->block != b2->block;
-}
-
-static INLINE int loop_attr_hash(const loop_attr_t *a) {
-#ifdef DEBUG_libfirm
- return a->loop->loop_nr;
-#else
- return HASH_PTR(a->loop);
-#endif
-}
-
-static INLINE int block_attr_hash(const block_attr_t *b) {
- return nodeset_hash(b->block);
-}
-
-static INLINE int loop_edge_hash(const loop_edge_t *e) {
- return nodeset_hash(e->block) ^ (e->pos * 31);
-}
-
-static INLINE loop_attr_t *get_loop_attr(morgan_env_t *env, const ir_loop *loop) {
- loop_attr_t l_attr, *res;
- int hash;
- l_attr.loop = loop;
-
- hash = loop_attr_hash(&l_attr);
- res = set_find(env->loop_attr_set, &l_attr, sizeof(l_attr), hash);
-
- // create new loop_attr if none exists yet
- if (res == NULL) {
- l_attr.out_edges = new_set(loop_edge_cmp, 1);
- l_attr.in_edges = new_set(loop_edge_cmp, 1);
- l_attr.livethrough_unused = bitset_obstack_alloc(&env->obst, get_irg_last_idx(env->irg));
- res = set_insert(env->loop_attr_set, &l_attr, sizeof(l_attr), hash);
- }
-
- return res;
-}
-
-static INLINE block_attr_t *get_block_attr(morgan_env_t *env, const ir_node *block) {
- block_attr_t b_attr, *res;
- int hash;
- b_attr.block = block;
-
- hash = block_attr_hash(&b_attr);
- res = set_find(env->block_attr_set, &b_attr, sizeof(b_attr), hash);
-
- if(res == NULL) {
- b_attr.livethrough_unused = NULL;
- res = set_insert(env->block_attr_set, &b_attr, sizeof(b_attr), hash);
- }
-
- return res;
-}
-
-//---------------------------------------------------------------------------
-
-static INLINE int consider_for_spilling(const arch_env_t *env, const arch_register_class_t *cls, const ir_node *node) {
- if(!arch_irn_has_reg_class(env, node, -1, cls))
- return 0;
-
- return !(arch_irn_get_flags(env, node) & (arch_irn_flags_ignore | arch_irn_flags_dont_spill));
-}
-
-/**
- * Determine edges going out of a loop (= edges that go to a block that is not
- * inside the loop or one of its subloops)
- */
-static INLINE void construct_loop_edges(ir_node *block, void *data) {
- morgan_env_t *env = data;
- int n_cfgpreds = get_Block_n_cfgpreds(block);
- int i;
- ir_loop* loop = get_irn_loop(block);
- DBG((dbg, DBG_LOOPANA, "Loop for %+F: %d (depth %d)\n", block, loop->loop_nr, loop->depth));
-
- for(i = 0; i < n_cfgpreds; ++i) {
- loop_edge_t edge;
- int hash;
- ir_node* cfgpred = get_Block_cfgpred(block, i);
- ir_node* cfgpred_block = get_nodes_block(cfgpred);
- ir_loop* cfgpred_loop = get_irn_loop(cfgpred_block);
-
- if(cfgpred_loop == loop)
- continue;
-
- assert(get_loop_depth(cfgpred_loop) != get_loop_depth(loop));
-
- edge.block = block;
- edge.pos = i;
- hash = loop_edge_hash(&edge);
-
- // edge out of a loop?
- if(get_loop_depth(cfgpred_loop) > get_loop_depth(loop)) {
- ir_loop *l;
-
- DBG((dbg, DBG_LOOPANA, "Loop out edge from %+F (loop %d) to %+F (loop %d)\n", block, get_loop_loop_nr(loop),
- cfgpred_block, get_loop_loop_nr(cfgpred_loop)));
-
- /* this might be a jump out of multiple loops, so add this to all
- * needed outedge sets */
- l = cfgpred_loop;
- do {
- loop_attr_t *l_attr = get_loop_attr(env, l);
- set_insert(l_attr->out_edges, &edge, sizeof(edge), hash);
-
- l = get_loop_outer_loop(l);
- assert(l != NULL);
- } while(l != loop);
- } else {
- ir_loop *l;
-
- // edge into a loop
- DBG((dbg, DBG_LOOPANA, "Loop in edge from %+F (loop %d) to %+F (loop %d)\n", block, get_loop_loop_nr(loop),
- cfgpred_block, get_loop_loop_nr(cfgpred_loop)));
-
- l = loop;
- do {
- loop_attr_t *l_attr = get_loop_attr(env, l);
- set_insert(l_attr->in_edges, &edge, sizeof(edge), hash);
-
- l = get_loop_outer_loop(l);
- } while(l != cfgpred_loop);
- }
- }
-}
-
-static void free_loop_edges(morgan_env_t *env) {
- loop_attr_t *l_attr;
-
- for(l_attr = set_first(env->loop_attr_set); l_attr != NULL; l_attr = set_next(env->loop_attr_set)) {
- del_set(l_attr->out_edges);
- del_set(l_attr->in_edges);
- }
-}
-
-#if 0
-/**
- * Debugging help, shows all nodes in a (node-)bitset
- */
-static void show_nodebitset(ir_graph* irg, const bitset_t* bitset) {
- int i;
-
- bitset_foreach(bitset, i) {
- ir_node* node = get_idx_irn(irg, i);
- ir_fprintf(stderr, " %+F", node);
- }
- fprintf(stderr, "\n");
-}
-#endif
-
-static INLINE void init_livethrough_unuseds(block_attr_t *attr, morgan_env_t *env) {
- const ir_node *block;
- int i;
- const be_lv_t *lv = env->lv;
-
- if(attr->livethrough_unused != NULL)
- return;
-
- block = attr->block;
-
- attr->livethrough_unused = bitset_obstack_alloc(&env->obst, get_irg_last_idx(env->irg));
-
- // copy all live-outs into the livethrough_unused set
- be_lv_foreach(lv, block, be_lv_state_in | be_lv_state_out, i) {
- ir_node *irn = be_lv_get_irn(lv, block, i);
- int node_idx;
-
- if(!consider_for_spilling(env->arch, env->cls, irn))
- continue;
-
- node_idx = get_irn_idx(irn);
- bitset_set(attr->livethrough_unused, node_idx);
- }
-}
-
-/**
- * Construct the livethrough unused set for a block
- */
-static void construct_block_livethrough_unused(ir_node *block, void *data) {
- morgan_env_t* env = data;
- block_attr_t *block_attr = get_block_attr(env, block);
- ir_node *node;
- int n_cfgpreds;
- block_attr_t **pred_attrs = NULL;
- int i;
-
- init_livethrough_unuseds(block_attr, env);
-
- DBG((dbg, DBG_LIVE, "Processing block %d\n", get_irn_node_nr(block)));
-
- n_cfgpreds = get_Block_n_cfgpreds(block);
- if(n_cfgpreds > 1) {
- pred_attrs = alloca(sizeof(pred_attrs[0]) * n_cfgpreds);
- for(i = 0; i < n_cfgpreds; ++i) {
- ir_node *pred_block = get_Block_cfgpred_block(block, i);
- pred_attrs[i] = get_block_attr(env, pred_block);
- init_livethrough_unuseds(pred_attrs[i], env);
- }
- }
-
- /*
- * All values that are used within the block are not unused (and therefore not
- * livethrough_unused)
- *
- * TODO FIXME use block out edges and not schedule to find uses
- */
- panic("needs fixing");
- sched_foreach(block, node) {
- int i, arity;
-
- // phis are really uses in the pred block
- if(is_Phi(node)) {
- int j;
- for(j = 0; j < n_cfgpreds; ++j) {
- ir_node *used_value = get_Phi_pred(node, j);
- int idx = get_irn_idx(used_value);
- block_attr_t *pred_attr = pred_attrs[j];
-
- bitset_clear(pred_attr->livethrough_unused, idx);
- }
- } else {
- // mark all used values as used
- for(i = 0, arity = get_irn_arity(node); i < arity; ++i) {
- int idx = get_irn_idx(get_irn_n(node, i));
- bitset_clear(block_attr->livethrough_unused, idx);
- }
- }
- }
-}
-
-/**
- * Construct the livethrough unused set for a loop (and all its subloops+blocks)
- */
-static bitset_t *construct_loop_livethrough_unused(morgan_env_t *env, const ir_loop *loop) {
- int i;
- loop_attr_t* loop_attr = get_loop_attr(env, loop);
-
- DBG((dbg, DBG_LIVE, "Processing Loop %d\n", loop->loop_nr));
- assert(get_loop_n_elements(loop) > 0);
- for(i = 0; i < get_loop_n_elements(loop); ++i) {
- loop_element elem = get_loop_element(loop, i);
- switch (*elem.kind) {
- case k_ir_node: {
- ir_node *block = elem.node;
- block_attr_t *block_attr = get_block_attr(env, block);
- bitset_t *livethrough_block_unused = block_attr->livethrough_unused;
-
- assert(is_Block(elem.node));
- assert(livethrough_block_unused != NULL);
-
- if(i == 0) {
- bitset_copy(loop_attr->livethrough_unused, livethrough_block_unused);
- } else {
- bitset_and(loop_attr->livethrough_unused, livethrough_block_unused);
- }
- break;
- }
- case k_ir_loop: {
- bitset_t *livethrough_son_unused;
-
- livethrough_son_unused = construct_loop_livethrough_unused(env, elem.son);
- if(i == 0) {
- bitset_copy(loop_attr->livethrough_unused, livethrough_son_unused);
- } else {
- bitset_and(loop_attr->livethrough_unused, livethrough_son_unused);
- }
- break;
- }
- default:
- assert(0);
- break;
- }
- }
- DBG((dbg, DBG_LIVE, "Done with loop %d\n", loop->loop_nr));
-
- // remove all unused livethroughs that are remembered for this loop from child loops and blocks
- for(i = 0; i < get_loop_n_elements(loop); ++i) {
- const loop_element elem = get_loop_element(loop, i);
-
- if(*elem.kind == k_ir_loop) {
- loop_attr_t *son_attr = get_loop_attr(env, elem.son);
- bitset_andnot(son_attr->livethrough_unused, loop_attr->livethrough_unused);
-
- DBG((dbg, DBG_LIVE, "Livethroughs for loop %d:\n", loop->loop_nr));
- } else if(*elem.kind == k_ir_node) {
- block_attr_t *block_attr = get_block_attr(env, elem.node);
- bitset_andnot(block_attr->livethrough_unused, loop_attr->livethrough_unused);
-
- DBG((dbg, DBG_LIVE, "Livethroughs for block %+F\n", elem.node));
- } else {
- assert(0);
- }
- }
-
- return loop_attr->livethrough_unused;
-}
-
-/*---------------------------------------------------------------------------*/
-
-typedef struct _spillcandidate_t {
- ir_node *node;
- double cost;
-} spillcandidate_t;
-
-static int compare_spillcandidates(const void *d1, const void *d2) {
- const spillcandidate_t *cand1 = d1;
- const spillcandidate_t *cand2 = d2;
-
- return (int)(cand1->cost - cand2->cost);
-}
-
-static void spill_values(morgan_env_t *env, const loop_attr_t *loop_attr, int spills) {
- const bitset_t *cand_bitset = loop_attr->livethrough_unused;
- int candidatecount = bitset_popcnt(cand_bitset);
- spillcandidate_t *candidates;
- bitset_pos_t idx;
- int i, c;
- loop_edge_t *edge;
-
- assert(spills <= candidatecount);
-
- candidates = alloca(sizeof(candidates[0]) * candidatecount);
-
- DBG((dbg, DBG_CHOOSE, "Candidates for loop %d\n", get_loop_loop_nr(loop_attr->loop)));
- // build candidiate list
- c = 0;
- bitset_foreach(cand_bitset, idx) {
- ir_node *node = get_idx_irn(env->irg, idx);
- candidates[c].node = node;
- candidates[c].cost = 0.0;
-
- for(edge = set_first(loop_attr->out_edges); edge != NULL; edge = set_next(loop_attr->out_edges)) {
- candidates[c].cost += be_get_reload_costs_on_edge(env->senv, node, edge->block, edge->pos);
- }
- DBG((dbg, DBG_CHOOSE, "%+F has costs %f\n", node, candidates[c].cost));
-
- c++;
- }
- assert(c == candidatecount);
-
- // sort list
- qsort(candidates, candidatecount, sizeof(candidates[0]), compare_spillcandidates);
-
- // spill values
- for(i = 0; i < spills; ++i) {
- ir_node *to_spill = candidates[i].node;
- DBG((dbg, DBG_CHOOSE, "Spilling %+F ", to_spill));
-
- for(edge = set_first(loop_attr->out_edges); edge != NULL; edge = set_next(loop_attr->out_edges)) {
- be_add_reload_on_edge(env->senv, to_spill, edge->block, edge->pos, env->cls, 1);
- }
- }
-}
-
-static int reduce_register_pressure_in_block(morgan_env_t *env, const ir_node* block, int loop_unused_spills_possible) {
- ir_node *node;
- int max_pressure;
- int loop_unused_spills_needed;
- ir_nodeset_t live_nodes;
- const be_lv_t *lv = env->lv;
-
- ir_nodeset_init(&live_nodes);
-
- be_liveness_end_of_block(lv, env->arch, env->cls, block, &live_nodes);
- max_pressure = ir_nodeset_size(&live_nodes);
-
- DBG((dbg, DBG_LIVE, "Reduce pressure to %d In Block %+F:\n", env->registers_available, block));
-
- /**
- * Determine register pressure in block
- */
- sched_foreach_reverse(block, node) {
- int pressure;
-
- if(is_Phi(node))
- break;
-
- be_liveness_transfer(env->arch, env->cls, node, &live_nodes);
- pressure = ir_nodeset_size(&live_nodes);
- if(pressure > max_pressure)
- max_pressure = pressure;
- }
- ir_nodeset_destroy(&live_nodes);
-
- loop_unused_spills_needed = max_pressure - env->registers_available;
-
- if(loop_unused_spills_needed < 0) {
- loop_unused_spills_needed = 0;
- } else if(loop_unused_spills_needed > loop_unused_spills_possible) {
- loop_unused_spills_needed = loop_unused_spills_possible;
- }
-
- DBG((dbg, DBG_PRESSURE, "Block %+F: max-pressure %d spills possible: %d spills used: %d\n",
- block, max_pressure, loop_unused_spills_possible, loop_unused_spills_needed));
- return loop_unused_spills_needed;
-}
-
-/**
- * Reduce register pressure in a loop
- *
- * @param unused_spills_possible Number of spills from livethrough_unused variables possible in outer loops
- * @return Number of spills of livethrough_unused variables needed in outer loops
- */
-static int reduce_register_pressure_in_loop(morgan_env_t *env, const ir_loop *loop, int outer_spills_possible) {
- int i;
- loop_attr_t* loop_attr = get_loop_attr(env, loop);
- int spills_needed = 0;
- int spills_possible = outer_spills_possible + bitset_popcnt(loop_attr->livethrough_unused);
- int outer_spills_needed;
-
- DBG((dbg, DBG_PRESSURE, "Reducing Pressure in loop %d\n", loop->loop_nr));
- for(i = 0; i < get_loop_n_elements(loop); ++i) {
- loop_element elem = get_loop_element(loop, i);
- switch (*elem.kind) {
- case k_ir_node: {
- int needed;
- assert(is_Block(elem.node));
- needed = reduce_register_pressure_in_block(env, elem.node, spills_possible);
- assert(needed >= 0);
- assert(needed <= spills_possible);
- if(needed > spills_needed)
- spills_needed = needed;
- break;
- }
- case k_ir_loop: {
- int needed = reduce_register_pressure_in_loop(env, elem.son, spills_possible);
- assert(needed >= 0);
- assert(needed <= spills_possible);
- if(needed > spills_needed)
- spills_needed = needed;
- break;
- }
- default:
- assert(0);
- break;
- }
- }
-
- /* calculate number of spills needed in outer loop and spill
- * unused livethrough nodes around this loop */
- if(spills_needed > outer_spills_possible) {
- int spills_to_place;
- outer_spills_needed = outer_spills_possible;
- spills_needed -= outer_spills_possible;
-
- spills_to_place = spills_needed;
-
- DBG((dbg, DBG_SPILLS, "%d values unused in loop %d, spilling %d\n",
- spills_possible - outer_spills_possible, loop->loop_nr, spills_to_place));
-
- spill_values(env, loop_attr, spills_to_place);
- } else {
- outer_spills_needed = spills_needed;
- }
-
- return outer_spills_needed;
-}
-
-void be_spill_morgan(be_irg_t *birg, const arch_register_class_t *cls) {
- ir_graph *irg = be_get_birg_irg(birg);
- morgan_env_t env;
-
- be_liveness_assure_sets(be_assure_liveness(birg));
-
- env.arch = birg->main_env->arch_env;
- env.irg = irg;
- env.cls = cls;
- env.lv = be_get_birg_liveness(birg);
- env.senv = be_new_spill_env(birg);
-
- obstack_init(&env.obst);
-
- env.registers_available = env.cls->n_regs - be_put_ignore_regs(birg, env.cls, NULL);
-
- env.loop_attr_set = new_set(loop_attr_cmp, 5);
- env.block_attr_set = new_set(block_attr_cmp, 20);
-
- /* -- Part1: Analysis -- */
-
- /* construct control flow loop tree */
- if (! (get_irg_loopinfo_state(irg) & loopinfo_cf_consistent)) {
- construct_cf_backedges(irg);
- }
-
- /* construct loop out edges and livethrough_unused sets for loops and blocks */
- irg_block_walk_graph(irg, construct_block_livethrough_unused, construct_loop_edges, &env);
- construct_loop_livethrough_unused(&env, get_irg_loop(irg));
-
- /* -- Part2: Transformation -- */
-
- /* spill unused livethrough values around loops and blocks where
- * the pressure is too high
- */
- reduce_register_pressure_in_loop(&env, get_irg_loop(irg), 0);
-
- /* Insert real spill/reload nodes and fix usages */
- be_insert_spills_reloads(env.senv);
-
- /* Verify the result */
- if (birg->main_env->options->vrfy_option == BE_VRFY_WARN) {
- be_verify_schedule(birg);
- } else if (birg->main_env->options->vrfy_option == BE_VRFY_ASSERT) {
- assert(be_verify_schedule(birg));
- }
-
- /* cleanup */
- free_loop_edges(&env);
- del_set(env.loop_attr_set);
- del_set(env.block_attr_set);
-
- /* fix the remaining places with too high register pressure with beladies algorithm */
- be_spill_belady_spill_env(birg, cls, env.senv);
-
- be_delete_spill_env(env.senv);
- obstack_free(&env.obst, NULL);
-}
-
-void be_init_spillmorgan(void)
-{
- static be_spiller_t morgan_spiller = {
- be_spill_morgan
- };
-
- be_register_spiller("morgan", &morgan_spiller);
- FIRM_DBG_REGISTER(dbg, "ir.be.spillmorgan");
-}
-
-BE_REGISTER_MODULE_CONSTRUCTOR(be_init_spillmorgan);
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