+ /* collect all registers occuring 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 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;