1646
1647 if (type()->isa_valuetypeptr() && can_reshape) {
1648 // If the Phi merges the result from a mix of constant and non
1649 // constant method handles, only some of its inputs are
1650 // ValueTypePtr nodes and we can't push the ValueTypePtr node down
1651 // to remove the need for allocations. This if fixed by transforming:
1652 //
1653 // (Phi ValueTypePtr#1 Node#2) to (Phi ValueTypePtr#1 CheckCastPP#2)
1654 //
1655 // Then pushing the CheckCastPP up through Phis until it reaches
1656 // the non constant method handle call. The type of the return
1657 // value is then known from the type of the CheckCastPP. A
1658 // ValueTypePtr can be created by adding projections to the call
1659 // for all values being returned. See
1660 // CheckCastPPNode::Ideal(). That ValueTypePtr node can then be
1661 // pushed down through Phis.
1662 const TypeValueTypePtr* vtptr = NULL;
1663 for (uint i = 1; i < req(); i++) {
1664 if (in(i) != NULL && in(i)->is_ValueTypePtr()) {
1665 const TypeValueTypePtr* t = phase->type(in(i))->is_valuetypeptr();
1666 if (vtptr == NULL) {
1667 vtptr = t;
1668 } else {
1669 assert(vtptr == t, "Phi should merge identical value types");
1670 }
1671 } else {
1672 assert(in(i) == NULL || vtptr == NULL || phase->type(in(i))->higher_equal(vtptr) || phase->type(in(i)) == Type::TOP ||
1673 phase->type(in(i))->is_valuetypeptr()->value_type()->value_klass() == phase->C->env()->___Value_klass(), "bad type");
1674 }
1675 }
1676 if (vtptr != NULL) {
1677 // One input is a value type. All inputs must have the same type.
1678 bool progress = false;
1679 PhaseIterGVN* igvn = phase->is_IterGVN();
1680 for (uint i = 1; i < req(); i++) {
1681 if (in(i) != NULL && !phase->type(in(i))->higher_equal(vtptr)) {
1682 // Can't transform because CheckCastPPNode::Identity can
1683 // push the cast up through another Phi and cause this same
1684 // transformation to run again, indefinitely
1685 Node* cast = igvn->register_new_node_with_optimizer(new CheckCastPPNode(NULL, in(i), vtptr));
1686 set_req(i, cast);
1687 progress = true;
1688 }
1689 }
1690 if (progress) {
1691 return this;
1692 }
1693 }
1694 }
1695
1696 Node *top = phase->C->top();
1697 bool new_phi = (outcnt() == 0); // transforming new Phi
1698 // No change for igvn if new phi is not hooked
1699 if (new_phi && can_reshape)
1700 return NULL;
1701
|
1646
1647 if (type()->isa_valuetypeptr() && can_reshape) {
1648 // If the Phi merges the result from a mix of constant and non
1649 // constant method handles, only some of its inputs are
1650 // ValueTypePtr nodes and we can't push the ValueTypePtr node down
1651 // to remove the need for allocations. This if fixed by transforming:
1652 //
1653 // (Phi ValueTypePtr#1 Node#2) to (Phi ValueTypePtr#1 CheckCastPP#2)
1654 //
1655 // Then pushing the CheckCastPP up through Phis until it reaches
1656 // the non constant method handle call. The type of the return
1657 // value is then known from the type of the CheckCastPP. A
1658 // ValueTypePtr can be created by adding projections to the call
1659 // for all values being returned. See
1660 // CheckCastPPNode::Ideal(). That ValueTypePtr node can then be
1661 // pushed down through Phis.
1662 const TypeValueTypePtr* vtptr = NULL;
1663 for (uint i = 1; i < req(); i++) {
1664 if (in(i) != NULL && in(i)->is_ValueTypePtr()) {
1665 const TypeValueTypePtr* t = phase->type(in(i))->is_valuetypeptr();
1666 t = t->cast_to_ptr_type(TypePtr::BotPTR)->is_valuetypeptr();
1667 if (vtptr == NULL) {
1668 vtptr = t;
1669 } else {
1670 assert(vtptr == t, "Phi should merge identical value types");
1671 }
1672 } else {
1673 assert(in(i) == NULL || vtptr == NULL || phase->type(in(i))->higher_equal(vtptr) || phase->type(in(i)) == Type::TOP ||
1674 phase->type(in(i))->is_valuetypeptr()->is__Value(), "bad type");
1675 }
1676 }
1677 if (vtptr != NULL) {
1678 // One input is a value type. All inputs must have the same type.
1679 bool progress = false;
1680 PhaseIterGVN* igvn = phase->is_IterGVN();
1681 for (uint i = 1; i < req(); i++) {
1682 if (in(i) != NULL && !in(i)->is_Con() && !phase->type(in(i))->higher_equal(vtptr)) {
1683 // Can't transform because CheckCastPPNode::Identity can
1684 // push the cast up through another Phi and cause this same
1685 // transformation to run again, indefinitely
1686 Node* cast = igvn->register_new_node_with_optimizer(new CheckCastPPNode(NULL, in(i), vtptr));
1687 set_req(i, cast);
1688 progress = true;
1689 }
1690 }
1691 if (progress) {
1692 return this;
1693 }
1694 }
1695 }
1696
1697 Node *top = phase->C->top();
1698 bool new_phi = (outcnt() == 0); // transforming new Phi
1699 // No change for igvn if new phi is not hooked
1700 if (new_phi && can_reshape)
1701 return NULL;
1702
|