-static be_insn_t *chordal_scan_insn(be_chordal_env_t *env, ir_node *irn)
-{
- be_insn_env_t ie;
-
- ie.ignore_colors = env->ignore_colors;
- ie.obst = env->obst;
- ie.cls = env->cls;
- return be_scan_insn(&ie, irn);
-}
-
-static ir_node *prepare_constr_insn(be_chordal_env_t *env, ir_node *irn)
-{
- bitset_t *tmp = bitset_alloca(env->cls->n_regs);
- bitset_t *def_constr = bitset_alloca(env->cls->n_regs);
- ir_node *bl = get_nodes_block(irn);
- const be_irg_t *birg = env->birg;
- be_lv_t *lv = birg->lv;
-
- be_insn_t *insn;
- int i, j;
-
- for (i = get_irn_arity(irn) - 1; i >= 0; --i) {
- ir_node *op = get_irn_n(irn, i);
- ir_node *copy;
- const arch_register_t *reg;
- const arch_register_req_t *req;
-
- req = arch_get_register_req(irn, i);
- if (req->cls != env->cls)
- continue;
-
- reg = arch_get_irn_register(op);
-
- if (reg == NULL || !arch_register_type_is(reg, ignore))
- continue;
- if (arch_register_type_is(reg, joker))
- continue;
-
- if (!arch_register_req_is(req, limited))
- continue;
-
- if (rbitset_is_set(req->limited, reg->index))
- continue;
-
- copy = be_new_Copy(env->cls, env->irg, bl, op);
- be_stat_ev("constr_copy", 1);
-
- sched_add_before(irn, copy);
- set_irn_n(irn, i, copy);
- DBG((dbg, LEVEL_3, "inserting ignore arg copy %+F for %+F pos %d\n", copy, irn, i));
- }
-
- insn = chordal_scan_insn(env, irn);
-
- if (!insn->has_constraints)
- goto end;
-
- /* insert copies for nodes that occur constrained more than once. */
- for (i = insn->use_start; i < insn->n_ops; ++i) {
- be_operand_t *op = &insn->ops[i];
-
- if (!op->has_constraints)
- continue;
-
- for (j = i + 1; j < insn->n_ops; ++j) {
- ir_node *copy;
- be_operand_t *a_op = &insn->ops[j];
-
- if (a_op->carrier != op->carrier || !a_op->has_constraints)
- continue;
-
- /* if the constraint is the same, no copy is necessary
- * TODO generalise unequal but overlapping constraints */
- if (a_op->req == op->req)
- continue;
-
- if (be_is_Copy(get_irn_n(insn->irn, a_op->pos)))
- continue;
-
- copy = be_new_Copy(env->cls, env->irg, bl, op->carrier);
- be_stat_ev("constr_copy", 1);
-
- sched_add_before(insn->irn, copy);
- set_irn_n(insn->irn, a_op->pos, copy);
- DBG((dbg, LEVEL_3, "inserting multiple constr copy %+F for %+F pos %d\n", copy, insn->irn, a_op->pos));
- }
- }
-
- /* collect all registers occurring in out constraints. */
- for (i = 0; i < insn->use_start; ++i) {
- be_operand_t *op = &insn->ops[i];
- if (op->has_constraints)
- bitset_or(def_constr, op->regs);
- }
-
- /*
- * insert copies for all constrained arguments living through the node
- * and being constrained to a register which also occurs in out constraints.
- */
- for (i = insn->use_start; i < insn->n_ops; ++i) {
- ir_node *copy;
- be_operand_t *op = &insn->ops[i];
-
- bitset_copy(tmp, op->regs);
- bitset_and(tmp, def_constr);
-
- /*
- * Check, if
- * 1) the operand is constrained.
- * 2) lives through the node.
- * 3) is constrained to a register occurring in out constraints.
- */
- if (!op->has_constraints ||
- !values_interfere(birg, insn->irn, op->carrier) ||
- bitset_popcnt(tmp) == 0)
- continue;
-
- /*
- * only create the copy if the operand is no copy.
- * this is necessary since the assure constraints phase inserts
- * Copies and Keeps for operands which must be different from the
- * results. Additional copies here would destroy this.
- */
- if (be_is_Copy(get_irn_n(insn->irn, op->pos)))
- continue;
-
- copy = be_new_Copy(env->cls, env->irg, bl, op->carrier);
-
- sched_add_before(insn->irn, copy);
- set_irn_n(insn->irn, op->pos, copy);
- DBG((dbg, LEVEL_3, "inserting constr copy %+F for %+F pos %d\n", copy, insn->irn, op->pos));
- be_liveness_update(lv, op->carrier);
- }
-
-end:
- obstack_free(env->obst, insn);
- return insn->next_insn;
-}
-
-static void pre_spill_prepare_constr_walker(ir_node *bl, void *data)
-{
- be_chordal_env_t *env = data;
- ir_node *irn;
- for (irn = sched_first(bl); !sched_is_end(irn);) {
- irn = prepare_constr_insn(env, irn);
- }
-}
-
-void be_pre_spill_prepare_constr(be_chordal_env_t *cenv)
-{
- irg_block_walk_graph(cenv->irg, pre_spill_prepare_constr_walker, NULL, cenv);
-}
-