- /* 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));
- }
- 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;
-
-
-/**
- * Walker: compute the spill slots
- */
-static void compute_spill_slots_walker(ir_node *spill, void *env) {
- ss_env_t *ssenv = env;
- ir_node *ctx;
- pmap_entry *entry;
- spill_slot_t *ss;
-
- if (!be_is_Spill(spill))
- 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) {
- 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);
- 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(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);
-}
-
-
-/**
- * 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; i<size; ++i) {
- /* for each spill slot */
- ir_node *n1;
- int tgt_slot = -1;
-
- DBG((ssenv->dbg, 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(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] */
-
- /* do we need a new slot? */
- if (tgt_slot == -1) {
- tgt_slot = used_slots;
- used_slots++;