2830 if (UncommonNullCast // Cutout for this technique
2831 && obj != null() // And not the -Xcomp stupid case?
2832 && !too_many_traps(reason)
2833 ) {
2834 if (speculating) {
2835 return true;
2836 }
2837 if (data == NULL)
2838 // Edge case: no mature data. Be optimistic here.
2839 return true;
2840 // If the profile has not seen a null, assume it won't happen.
2841 assert(java_bc() == Bytecodes::_checkcast ||
2842 java_bc() == Bytecodes::_instanceof ||
2843 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2844 return !data->as_BitData()->null_seen();
2845 }
2846 speculating = false;
2847 return false;
2848 }
2849
2850 //------------------------maybe_cast_profiled_receiver-------------------------
2851 // If the profile has seen exactly one type, narrow to exactly that type.
2852 // Subsequent type checks will always fold up.
2853 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2854 ciKlass* require_klass,
2855 ciKlass* spec_klass,
2856 bool safe_for_replace) {
2857 if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2858
2859 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2860
2861 // Make sure we haven't already deoptimized from this tactic.
2862 if (too_many_traps_or_recompiles(reason))
2863 return NULL;
2864
2865 // (No, this isn't a call, but it's enough like a virtual call
2866 // to use the same ciMethod accessor to get the profile info...)
2867 // If we have a speculative type use it instead of profiling (which
2868 // may not help us)
2869 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
|
2830 if (UncommonNullCast // Cutout for this technique
2831 && obj != null() // And not the -Xcomp stupid case?
2832 && !too_many_traps(reason)
2833 ) {
2834 if (speculating) {
2835 return true;
2836 }
2837 if (data == NULL)
2838 // Edge case: no mature data. Be optimistic here.
2839 return true;
2840 // If the profile has not seen a null, assume it won't happen.
2841 assert(java_bc() == Bytecodes::_checkcast ||
2842 java_bc() == Bytecodes::_instanceof ||
2843 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2844 return !data->as_BitData()->null_seen();
2845 }
2846 speculating = false;
2847 return false;
2848 }
2849
2850 void GraphKit::guard_klass_being_initialized(Node* klass) {
2851 int init_state_off = in_bytes(InstanceKlass::init_state_offset());
2852 Node* adr = basic_plus_adr(top(), klass, init_state_off);
2853 Node* init_state = LoadNode::make(_gvn, NULL, immutable_memory(), adr,
2854 adr->bottom_type()->is_ptr(), TypeInt::BYTE,
2855 T_BYTE, MemNode::unordered);
2856 init_state = _gvn.transform(init_state);
2857
2858 Node* being_initialized_state = makecon(TypeInt::make(InstanceKlass::being_initialized));
2859
2860 Node* chk = _gvn.transform(new CmpINode(being_initialized_state, init_state));
2861 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
2862
2863 { BuildCutout unless(this, tst, PROB_MAX);
2864 uncommon_trap(Deoptimization::Reason_initialized, Deoptimization::Action_reinterpret);
2865 }
2866 }
2867
2868 void GraphKit::guard_init_thread(Node* klass) {
2869 int init_thread_off = in_bytes(InstanceKlass::init_thread_offset());
2870 Node* adr = basic_plus_adr(top(), klass, init_thread_off);
2871
2872 Node* init_thread = LoadNode::make(_gvn, NULL, immutable_memory(), adr,
2873 adr->bottom_type()->is_ptr(), TypePtr::NOTNULL,
2874 T_ADDRESS, MemNode::unordered);
2875 init_thread = _gvn.transform(init_thread);
2876
2877 Node* cur_thread = _gvn.transform(new ThreadLocalNode());
2878
2879 Node* chk = _gvn.transform(new CmpPNode(cur_thread, init_thread));
2880 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
2881
2882 { BuildCutout unless(this, tst, PROB_MAX);
2883 uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
2884 }
2885 }
2886
2887 void GraphKit::clinit_barrier(ciInstanceKlass* ik, ciMethod* context) {
2888 if (ik->is_being_initialized()) {
2889 if (C->needs_clinit_barrier(ik, context)) {
2890 Node* klass = makecon(TypeKlassPtr::make(ik));
2891 guard_klass_being_initialized(klass);
2892 guard_init_thread(klass);
2893 insert_mem_bar(Op_MemBarCPUOrder);
2894 }
2895 } else if (ik->is_initialized()) {
2896 return; // no barrier needed
2897 } else {
2898 uncommon_trap(Deoptimization::Reason_uninitialized,
2899 Deoptimization::Action_reinterpret,
2900 NULL);
2901 }
2902 }
2903
2904 //------------------------maybe_cast_profiled_receiver-------------------------
2905 // If the profile has seen exactly one type, narrow to exactly that type.
2906 // Subsequent type checks will always fold up.
2907 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2908 ciKlass* require_klass,
2909 ciKlass* spec_klass,
2910 bool safe_for_replace) {
2911 if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2912
2913 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2914
2915 // Make sure we haven't already deoptimized from this tactic.
2916 if (too_many_traps_or_recompiles(reason))
2917 return NULL;
2918
2919 // (No, this isn't a call, but it's enough like a virtual call
2920 // to use the same ciMethod accessor to get the profile info...)
2921 // If we have a speculative type use it instead of profiling (which
2922 // may not help us)
2923 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
|