-/*
- * Author: Daniel Grund, Sebastian Hack, Matthias Braun
- * Date: 29.09.2005
+/**
+ * @file
+ * @author Daniel Grund, Sebastian Hack, Matthias Braun
+ * @date 29.09.2005
+ * @version $Id$
* Copyright: (c) Universitaet Karlsruhe
* Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
*/
#include "irgwalk.h"
#include "array.h"
#include "pdeq.h"
-#include "unionfind.h"
#include "execfreq.h"
+#include "irnodeset.h"
#include "belive_t.h"
#include "besched_t.h"
#include "benodesets.h"
#include "bespilloptions.h"
#include "bestatevent.h"
+#include "bessaconstr.h"
// only rematerialise when costs are less than REMAT_COST_LIMIT
// TODO determine a good value here...
struct _reloader_t {
reloader_t *next;
- ir_node *reloader;
+ ir_node *reloader;
+ ir_node *rematted_node;
+ int allow_remat; /**< the node may be rematted instead of reloaded if global remat option is on */
};
typedef struct _spill_info_t {
/** if we had the value of a phi spilled before but not the phi itself then
* this field contains the spill for the phi value */
ir_node *old_spill;
+
+ /** the register class in which the reload should be placed */
+ const arch_register_class_t *reload_cls;
} spill_info_t;
struct _spill_env_t {
- const arch_register_class_t *cls;
const arch_env_t *arch_env;
- const be_chordal_env_t *chordal_env;
+ ir_graph *irg;
struct obstack obst;
be_irg_t *birg;
int spill_cost; /**< the cost of a single spill node */
int reload_cost; /**< the cost of a reload node */
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_nodeset_t mem_phis; /**< set of all special spilled phis. allocated and freed separately */
DEBUG_ONLY(firm_dbg_module_t *dbg;)
};
info.reloaders = NULL;
info.spill = NULL;
info.old_spill = NULL;
+ info.reload_cls = NULL;
res = set_insert(env->spills, &info, sizeof(info), hash);
}
return res;
}
-DEBUG_ONLY(
+#ifdef DEBUG_libfirm
/* 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;
}
-)
+#endif
/* Creates a new spill environment. */
-spill_env_t *be_new_spill_env(const be_chordal_env_t *chordal_env) {
+spill_env_t *be_new_spill_env(be_irg_t *birg) {
spill_env_t *env = xmalloc(sizeof(env[0]));
env->spills = new_set(cmp_spillinfo, 1024);
- env->cls = chordal_env->cls;
- env->chordal_env = chordal_env;
- env->birg = chordal_env->birg;
- env->arch_env = env->chordal_env->birg->main_env->arch_env;
- env->mem_phis = pset_new_ptr_default();
- // TODO, ask backend about costs...
+ env->irg = be_get_birg_irg(birg);
+ env->birg = birg;
+ env->arch_env = birg->main_env->arch_env;
+ ir_nodeset_init(&env->mem_phis);
+ // TODO, ask backend about costs..., or even ask backend whether we should
+ // rematerialize...
env->spill_cost = 8;
env->reload_cost = 5;
obstack_init(&env->obst);
/* Deletes a spill environment. */
void be_delete_spill_env(spill_env_t *env) {
del_set(env->spills);
- del_pset(env->mem_phis);
+ ir_nodeset_destroy(&env->mem_phis);
obstack_free(&env->obst, NULL);
free(env);
}
*
*/
-void be_add_reload(spill_env_t *env, ir_node *to_spill, ir_node *before) {
+void be_add_remat(spill_env_t *env, ir_node *to_spill, ir_node *before, ir_node *rematted_node) {
+ spill_info_t *spill_info;
+ reloader_t *reloader;
+
+ spill_info = get_spillinfo(env, to_spill);
+
+ /* add the remat information */
+ reloader = obstack_alloc(&env->obst, sizeof(reloader[0]));
+ reloader->next = spill_info->reloaders;
+ reloader->reloader = before;
+ reloader->rematted_node = rematted_node;
+ reloader->allow_remat = 1;
+
+ spill_info->reloaders = reloader;
+
+ DBG((env->dbg, LEVEL_1, "creating spillinfo for %+F, will be rematerialized before %+F\n",
+ to_spill, before));
+}
+
+void be_add_reload(spill_env_t *env, ir_node *to_spill, ir_node *before,
+ const arch_register_class_t *reload_cls, int allow_remat)
+{
spill_info_t *info;
reloader_t *rel;
- assert(arch_irn_consider_in_reg_alloc(env->arch_env, env->cls, to_spill));
-
info = get_spillinfo(env, to_spill);
- if(is_Phi(to_spill)) {
+ if (is_Phi(to_spill)) {
int i, arity;
- // create spillinfos for the phi arguments
- for(i = 0, arity = get_irn_arity(to_spill); i < arity; ++i) {
+
+ /* create spillinfos for the phi arguments */
+ for (i = 0, arity = get_irn_arity(to_spill); i < arity; ++i) {
ir_node *arg = get_irn_n(to_spill, i);
get_spillinfo(env, arg);
}
// the belady algo decides later to spill the whole phi, then sees the
// spill node and adds a reload for that spill node, problem is the
// reload gets attach to that same spill (and is totally unnecessary)
- if(info->old_spill != NULL &&
- (before == info->old_spill || value_dominates(before, info->old_spill))) {
+ if (info->old_spill != NULL &&
+ (before == info->old_spill || value_dominates(before, info->old_spill)))
+ {
printf("spilledphi hack was needed...\n");
before = sched_next(info->old_spill);
}
#endif
}
- rel = obstack_alloc(&env->obst, sizeof(rel[0]));
- rel->reloader = before;
- rel->next = info->reloaders;
- info->reloaders = rel;
+ /* put reload into list */
+ rel = obstack_alloc(&env->obst, sizeof(rel[0]));
+ rel->next = info->reloaders;
+ rel->reloader = before;
+ rel->rematted_node = NULL;
+ rel->allow_remat = allow_remat;
+
+ info->reloaders = rel;
+ assert(info->reload_cls == NULL || info->reload_cls == reload_cls);
+ info->reload_cls = reload_cls;
+
+ DBG((env->dbg, LEVEL_1, "creating spillinfo for %+F, will be reloaded before %+F, may%s be rematerialized\n",
+ to_spill, before, allow_remat ? "" : " not"));
}
-static ir_node *get_reload_insertion_point(ir_node *block, int pos) {
+/**
+ * Returns the point at which you can insert a node that should be executed
+ * before block @p block when coming from pred @p pos.
+ */
+static ir_node *get_block_insertion_point(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)
- */
+ /* 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)));
return sched_first(block);
}
if(!is_cfop(last)) {
- ir_graph *irg = get_irn_irg(block);
- ir_node *startblock = get_irg_start_block(irg);
-
last = sched_next(last);
// last node must be a cfop, only exception is the start block
- assert(last == startblock);
+ assert(last == get_irg_start_block(get_irn_irg(block)));
}
// add the reload before the (cond-)jump
return last;
}
-void be_add_reload_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos) {
- ir_node *before = get_reload_insertion_point(block, pos);
- be_add_reload(env, to_spill, before);
+void be_add_reload_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos,
+ const arch_register_class_t *reload_cls, int allow_remat)
+{
+ ir_node *before = get_block_insertion_point(block, pos);
+ be_add_reload(env, to_spill, before, reload_cls, allow_remat);
}
void be_spill_phi(spill_env_t *env, ir_node *node) {
assert(is_Phi(node));
- pset_insert_ptr(env->mem_phis, node);
+ ir_nodeset_insert(&env->mem_phis, node);
// create spillinfos for the phi arguments
spill = get_spillinfo(env, node);
*/
/**
- * Schedules a node after an instruction. (That is the place after all projs and phis
- * that are scheduled after the instruction)
- * This function also skips phi nodes at the beginning of a block
+ * Schedules a node after an instruction. That is the place after all projs and
+ * phis that are scheduled after the instruction. This function also skips phi
+ * nodes at the beginning of a block
*/
static void sched_add_after_insn(ir_node *sched_after, ir_node *node) {
ir_node *next = sched_next(sched_after);
* @return a be_Spill node
*/
static void spill_irn(spill_env_t *env, spill_info_t *spillinfo) {
- ir_node *to_spill = spillinfo->spilled_node;
+ optimization_state_t opt;
+ ir_node *to_spill = spillinfo->spilled_node;
- DBG((env->dbg, LEVEL_1, "%+F\n", to_spill));
+ DBG((env->dbg, LEVEL_1, "spilling %+F ... ", to_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
*
- * (although rematerialization code should handle most of these cases
- * this can still happen when spilling Phis)
+ * Normally reloads get simply rematerialized instead of spilled again; this
+ * can happen annyway when the reload is the pred of a phi to spill)
*/
- if(be_is_Reload(to_spill)) {
+ if (be_is_Reload(to_spill)) {
spillinfo->spill = get_irn_n(to_spill, be_pos_Reload_mem);
+ DB((env->dbg, LEVEL_1, "skip reload, using existing spill %+F\n", spillinfo->spill));
return;
}
- if (arch_irn_is(env->arch_env, to_spill, dont_spill)) {
- if (env->chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN)
- ir_fprintf(stderr, "Verify warning: spilling 'dont_spill' node %+F\n", to_spill);
- else if (env->chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT)
- assert(0 && "Attempt to spill a node marked 'dont_spill'");
+ assert(!(arch_irn_is(env->arch_env, to_spill, dont_spill)
+ && "Attempt to spill a node marked 'dont_spill'"));
+
+ /* some backends have virtual noreg/unknown nodes that are not scheduled */
+ if(!sched_is_scheduled(to_spill)) {
+ spillinfo->spill = new_NoMem();
+ return;
}
+
+ /*
+ We switch on optimizations here to get CSE. This is needed as some
+ backends have some extra spill phases and we want to make use of those
+ spills instead of creating new ones.
+ */
+ save_optimization_state(&opt);
+ set_optimize(1);
spillinfo->spill = be_spill(env->arch_env, to_spill);
- sched_add_after_insn(to_spill, spillinfo->spill);
+ restore_optimization_state(&opt);
+ if (! sched_is_scheduled(spillinfo->spill)) {
+ DB((env->dbg, LEVEL_1, "add spill %+F after %+F\n", spillinfo->spill, to_spill));
+ sched_add_after_insn(to_spill, spillinfo->spill);
+ } else {
+ DB((env->dbg, LEVEL_1, "re-using spill %+F after %+F\n", spillinfo->spill, to_spill));
+ }
}
static void spill_node(spill_env_t *env, spill_info_t *spillinfo);
assert(is_Phi(phi));
+ DBG((env->dbg, LEVEL_1, "spilling Phi %+F:\n", phi));
/* build a new PhiM */
ins = alloca(sizeof(ir_node*) * arity);
for(i = 0; i < arity; ++i) {
- ins[i] = get_irg_bad(env->chordal_env->irg);
+ ins[i] = get_irg_bad(env->irg);
}
- spillinfo->spill = new_r_Phi(env->chordal_env->irg, block, arity, ins, mode_M);
+ spillinfo->spill = new_r_Phi(env->irg, block, arity, ins, mode_M);
for(i = 0; i < arity; ++i) {
ir_node *arg = get_irn_n(phi, i);
set_irn_n(spillinfo->spill, i, arg_info->spill);
}
+ DBG((env->dbg, LEVEL_1, "... done spilling Phi %+F, created PhiM %+F\n", phi, spillinfo->spill));
// rewire reloads from old_spill to phi
- if(spillinfo->old_spill != NULL) {
+ if (spillinfo->old_spill != NULL) {
const ir_edge_t *edge, *next;
ir_node *old_spill = spillinfo->old_spill;
+ DBG((env->dbg, LEVEL_1, "old spill found, rewiring reloads:\n"));
+
foreach_out_edge_safe(old_spill, edge, next) {
- ir_node* reload = get_edge_src_irn(edge);
+ ir_node *reload = get_edge_src_irn(edge);
+ int pos = get_edge_src_pos(edge);
+
+ DBG((env->dbg, LEVEL_1, "\tset input %d of %+F to %+F\n", pos, reload, spillinfo->spill));
+
assert(be_is_Reload(reload) || is_Phi(reload));
- set_irn_n(reload, get_edge_src_pos(edge), spillinfo->spill);
+ set_irn_n(reload, pos, spillinfo->spill);
}
- set_irn_n(old_spill, be_pos_Spill_frame, new_Bad());
+ DBG((env->dbg, LEVEL_1, "\tset input of %+F to BAD\n", old_spill));
set_irn_n(old_spill, be_pos_Spill_val, new_Bad());
//sched_remove(old_spill);
spillinfo->old_spill = NULL;
return;
to_spill = spillinfo->spilled_node;
- if (is_Phi(to_spill) && pset_find_ptr(env->mem_phis, spillinfo->spilled_node)) {
+
+ if (is_Phi(to_spill) && ir_nodeset_contains(&env->mem_phis, to_spill)) {
spill_phi(env, spillinfo);
} else {
spill_irn(env, spillinfo);
if(be_is_Spill(arg))
return 1;
- if(arg == get_irg_frame(env->chordal_env->irg))
+ if(arg == get_irg_frame(env->irg))
return 1;
// hack for now (happens when command should be inserted at end of block)
return 0;
}
+ /*
+ * Ignore registers are always available
+ */
+ if(arch_irn_is(env->arch_env, arg, ignore)) {
+ return 1;
+ }
+
+#if 0
/* the following test does not work while spilling,
* because the liveness info is not adapted yet to the effects of the
* additional spills/reloads.
- *
- * So we can only do this test for ignore registers (of our register class)
*/
- if(arch_get_irn_reg_class(env->arch_env, arg, -1) == env->chordal_env->cls
- && arch_irn_is(env->arch_env, arg, ignore)) {
- int i, arity;
- /* we want to remat before the insn reloader
- * thus an arguments is alive if
- * - it interferes with the reloaders result
- * - or it is (last-) used by reloader itself
- */
- if (values_interfere(env->birg->lv, reloader, arg)) {
- return 1;
- }
+ /* we want to remat before the insn reloader
+ * thus an arguments is alive if
+ * - it interferes with the reloaders result
+ * - or it is (last-) used by reloader itself
+ */
+ if (values_interfere(env->birg->lv, reloader, arg)) {
+ return 1;
+ }
- arity = get_irn_arity(reloader);
- for (i = 0; i < arity; ++i) {
- ir_node *rel_arg = get_irn_n(reloader, i);
- if (rel_arg == arg)
- return 1;
- }
+ arity = get_irn_arity(reloader);
+ for (i = 0; i < arity; ++i) {
+ ir_node *rel_arg = get_irn_n(reloader, i);
+ if (rel_arg == arg)
+ return 1;
}
+#endif
return 0;
}
}
/* create a copy of the node */
- res = new_ir_node(get_irn_dbg_info(spilled), env->chordal_env->irg, bl,
+ res = new_ir_node(get_irn_dbg_info(spilled), env->irg, bl,
get_irn_op(spilled),
get_irn_mode(spilled),
get_irn_arity(spilled),
ins);
copy_node_attr(spilled, res);
new_backedge_info(res);
+ sched_reset(res);
- DBG((env->dbg, LEVEL_1, "Insert remat %+F before reloader %+F\n", res, reloader));
+ DBG((env->dbg, LEVEL_1, "Insert remat %+F of %+F before reloader %+F\n", res, spilled, reloader));
/* insert in schedule */
sched_add_before(reloader, res);
}
int be_get_reload_costs_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos) {
- ir_node *before = get_reload_insertion_point(block, pos);
+ ir_node *before = get_block_insertion_point(block, pos);
return be_get_reload_costs(env, to_spill, before);
}
void be_insert_spills_reloads(spill_env_t *env) {
const arch_env_t *arch_env = env->arch_env;
- spill_info_t *si;
- int remats = 0;
- int reloads = 0;
- int spills = 0;
+ int remats = 0;
+ int reloads = 0;
+ int spills = 0;
+ spill_info_t *si;
+ ir_nodeset_iterator_t iter;
+ ir_node *node;
+
+ /* create all phi-ms first, this is needed so, that phis, hanging on
+ spilled phis work correctly */
+ foreach_ir_nodeset(&env->mem_phis, node, iter) {
+ spill_info_t *info = get_spillinfo(env, node);
+ spill_node(env, info);
+ }
/* process each spilled node */
- for(si = set_first(env->spills); si; si = set_next(env->spills)) {
+ 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);
+ ir_node *spilled_node = si->spilled_node;
+ ir_mode *mode = get_irn_mode(spilled_node);
+ ir_node **copies = NEW_ARR_F(ir_node*, 0);
+
+ DBG((env->dbg, LEVEL_1, "\nhandling all reloaders of %+F:\n", spilled_node));
/* go through all reloads for this spill */
- for(rld = si->reloaders; rld; rld = rld->next) {
- ir_node *new_val;
+ for (rld = si->reloaders; rld; rld = rld->next) {
+ ir_node *copy; /* a reaload is a "copy" of the original value */
- if (be_do_remats && check_remat_conditions(env, si->spilled_node, rld->reloader)) {
- new_val = do_remat(env, si->spilled_node, rld->reloader);
+ if (rld->rematted_node != NULL) {
+ copy = rld->rematted_node;
+ remats++;
+ sched_add_before(rld->reloader, copy);
+ } else if (be_do_remats && rld->allow_remat &&
+ check_remat_conditions(env, spilled_node, rld->reloader)) {
+ copy = do_remat(env, spilled_node, rld->reloader);
remats++;
} else {
/* make sure we have a spill */
- if(si->spill == NULL) {
+ if (si->spill == NULL) {
spill_node(env, si);
spills++;
}
/* create a reload */
- new_val = be_reload(arch_env, env->cls, rld->reloader, mode, si->spill);
+ copy = be_reload(arch_env, si->reload_cls, rld->reloader, mode, si->spill);
reloads++;
}
- DBG((env->dbg, LEVEL_1, " %+F of %+F before %+F\n", new_val, si->spilled_node, rld->reloader));
- pset_insert_ptr(values, new_val);
+ DBG((env->dbg, LEVEL_1, " %+F of %+F before %+F\n",
+ copy, spilled_node, rld->reloader));
+ ARR_APP1(ir_node*, copies, copy);
}
- if(pset_count(values) > 0) {
- /* introduce copies, rewire the uses */
- pset_insert_ptr(values, si->spilled_node);
- be_ssa_constr_set_ignore(env->birg->dom_front, env->birg->lv, values, env->mem_phis);
+ /* if we had any reloads or remats, then we need to reconstruct the
+ * SSA form for the spilled value */
+ if (ARR_LEN(copies) > 0) {
+ be_ssa_construction_env_t senv;
+ /* be_lv_t *lv = be_get_birg_liveness(env->birg); */
+
+ be_ssa_construction_init(&senv, env->birg);
+ be_ssa_construction_add_copy(&senv, spilled_node);
+ be_ssa_construction_add_copies(&senv, copies, ARR_LEN(copies));
+ be_ssa_construction_fix_users(&senv, spilled_node);
+
+#if 0
+ /* no need to enable this as long as we invalidate liveness
+ after this function... */
+ be_ssa_construction_update_liveness_phis(&senv);
+ be_liveness_update(spilled_node);
+ len = ARR_LEN(copies);
+ for(i = 0; i < len; ++i) {
+ be_liveness_update(lv, copies[i]);
+ }
+#endif
+ be_ssa_construction_destroy(&senv);
}
- del_pset(values);
-
+ DEL_ARR_F(copies);
si->reloaders = NULL;
}
- if(be_stat_ev_is_active()) {
+#ifdef FIRM_STATISTICS
+ if (be_stat_ev_is_active()) {
be_stat_ev("spill_spills", spills);
be_stat_ev("spill_reloads", reloads);
be_stat_ev("spill_remats", remats);
}
+#endif /* FIRM_STATISTICS */
- be_remove_dead_nodes_from_schedule(env->chordal_env->irg);
- //be_liveness_recompute(env->birg->lv);
+ be_remove_dead_nodes_from_schedule(env->irg);
+ /* Matze: In theory be_ssa_construction should take care of the livenes...
+ * try to disable this again in the future */
be_invalidate_liveness(env->birg);
}