+ /*
+ Check, if
+ 1) the operand is constrained.
+ 2) lives through the node.
+ 3) is constrained to a register occuring 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, (void *) cenv);