950 //
951 // "All bets are off" unless the first publication occurs after a
952 // normal return from the constructor. We do not attempt to detect
953 // such unusual early publications. But no barrier is needed on
954 // exceptional returns, since they cannot publish normally.
955 //
956 if (method()->is_initializer() &&
957 (wrote_final() ||
958 PPC64_ONLY(wrote_volatile() ||)
959 (AlwaysSafeConstructors && wrote_fields()))) {
960 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
961 #ifndef PRODUCT
962 if (PrintOpto && (Verbose || WizardMode)) {
963 method()->print_name();
964 tty->print_cr(" writes finals and needs a memory barrier");
965 }
966 #endif
967 }
968
969 // Any method can write a @Stable field; insert memory barriers after
970 // those also. If there is a predecessor allocation node, bind the
971 // barrier there.
972 if (wrote_stable()) {
973 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
974 #ifndef PRODUCT
975 if (PrintOpto && (Verbose || WizardMode)) {
976 method()->print_name();
977 tty->print_cr(" writes @Stable and needs a memory barrier");
978 }
979 #endif
980 }
981
982 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
983 // transform each slice of the original memphi:
984 mms.set_memory(_gvn.transform(mms.memory()));
985 }
986
987 if (tf()->range()->cnt() > TypeFunc::Parms) {
988 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
989 Node* ret_phi = _gvn.transform( _exits.argument(0) );
990 if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
991 // In case of concurrent class loading, the type we set for the
992 // ret_phi in build_exits() may have been too optimistic and the
993 // ret_phi may be top now.
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950 //
951 // "All bets are off" unless the first publication occurs after a
952 // normal return from the constructor. We do not attempt to detect
953 // such unusual early publications. But no barrier is needed on
954 // exceptional returns, since they cannot publish normally.
955 //
956 if (method()->is_initializer() &&
957 (wrote_final() ||
958 PPC64_ONLY(wrote_volatile() ||)
959 (AlwaysSafeConstructors && wrote_fields()))) {
960 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
961 #ifndef PRODUCT
962 if (PrintOpto && (Verbose || WizardMode)) {
963 method()->print_name();
964 tty->print_cr(" writes finals and needs a memory barrier");
965 }
966 #endif
967 }
968
969 // Any method can write a @Stable field; insert memory barriers after
970 // those also. Can't bind predecessor allocation node with barrier.
971 // Because allocation doesn't always dominate MemBarRelease. Example
972 // foo(StableFieldObject s) {
973 // if (s != null) return s;
974 // s = new StableFieldObject();
975 // s.stable = 1;
976 // }
977 // MemBarRelease inserted at exit is not dominated by allocation
978 // (early return path might take) and will trigger assertion when
979 // verify_dominance, because use (MemBarRelease) is not dominate by
980 // def (allocation).
981 if (wrote_stable()) {
982 _exits.insert_mem_bar(Op_MemBarRelease);
983 #ifndef PRODUCT
984 if (PrintOpto && (Verbose || WizardMode)) {
985 method()->print_name();
986 tty->print_cr(" writes @Stable and needs a memory barrier");
987 }
988 #endif
989 }
990
991 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
992 // transform each slice of the original memphi:
993 mms.set_memory(_gvn.transform(mms.memory()));
994 }
995
996 if (tf()->range()->cnt() > TypeFunc::Parms) {
997 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
998 Node* ret_phi = _gvn.transform( _exits.argument(0) );
999 if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
1000 // In case of concurrent class loading, the type we set for the
1001 // ret_phi in build_exits() may have been too optimistic and the
1002 // ret_phi may be top now.
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