61 if (member.getDeclaringClass().isInterface() &&
62 member.getReferenceKind() == REF_invokeInterface &&
63 member.isMethod() && !member.isAbstract()) {
64 // Check for corner case: invokeinterface of Object method
65 MemberName m = new MemberName(Object.class, member.getName(), member.getMethodType(), member.getReferenceKind());
66 m = MemberName.getFactory().resolveOrNull(m.getReferenceKind(), m, null, LM_TRUSTED);
67 if (m != null && m.isPublic()) {
68 assert(member.getReferenceKind() == m.getReferenceKind()); // else this.form is wrong
69 member = m;
70 }
71 }
72
73 this.member = member;
74 this.crackable = crackable;
75 }
76
77 // Factory methods:
78 static DirectMethodHandle make(byte refKind, Class<?> refc, MemberName member, Class<?> callerClass) {
79 MethodType mtype = member.getMethodOrFieldType();
80 if (!member.isStatic()) {
81 if (!member.getDeclaringClass().isAssignableFrom(refc) || member.isConstructor())
82 throw new InternalError(member.toString());
83 mtype = mtype.insertParameterTypes(0, refc);
84 }
85 if (!member.isField()) {
86 // refKind reflects the original type of lookup via findSpecial or
87 // findVirtual etc.
88 return switch (refKind) {
89 case REF_invokeSpecial -> {
90 member = member.asSpecial();
91 // if caller is an interface we need to adapt to get the
92 // receiver check inserted
93 if (callerClass == null) {
94 throw new InternalError("callerClass must not be null for REF_invokeSpecial");
95 }
96 LambdaForm lform = preparedLambdaForm(member, callerClass.isInterface());
97 yield new Special(mtype, lform, member, true, callerClass);
98 }
99 case REF_invokeInterface -> {
100 // for interfaces we always need the receiver typecheck,
101 // so we always pass 'true' to ensure we adapt if needed
102 // to include the REF_invokeSpecial case
103 LambdaForm lform = preparedLambdaForm(member, true);
111 } else {
112 LambdaForm lform = preparedFieldLambdaForm(member);
113 if (member.isStatic()) {
114 long offset = MethodHandleNatives.staticFieldOffset(member);
115 Object base = MethodHandleNatives.staticFieldBase(member);
116 return new StaticAccessor(mtype, lform, member, true, base, offset);
117 } else {
118 long offset = MethodHandleNatives.objectFieldOffset(member);
119 assert(offset == (int)offset);
120 return new Accessor(mtype, lform, member, true, (int)offset);
121 }
122 }
123 }
124 static DirectMethodHandle make(Class<?> refc, MemberName member) {
125 byte refKind = member.getReferenceKind();
126 if (refKind == REF_invokeSpecial)
127 refKind = REF_invokeVirtual;
128 return make(refKind, refc, member, null /* no callerClass context */);
129 }
130 static DirectMethodHandle make(MemberName member) {
131 if (member.isConstructor())
132 return makeAllocator(member);
133 return make(member.getDeclaringClass(), member);
134 }
135 private static DirectMethodHandle makeAllocator(MemberName ctor) {
136 assert(ctor.isConstructor() && ctor.getName().equals("<init>"));
137 Class<?> instanceClass = ctor.getDeclaringClass();
138 ctor = ctor.asConstructor();
139 assert(ctor.isConstructor() && ctor.getReferenceKind() == REF_newInvokeSpecial) : ctor;
140 MethodType mtype = ctor.getMethodType().changeReturnType(instanceClass);
141 LambdaForm lform = preparedLambdaForm(ctor);
142 MemberName init = ctor.asSpecial();
143 assert(init.getMethodType().returnType() == void.class);
144 return new Constructor(mtype, lform, ctor, true, init, instanceClass);
145 }
146
147 @Override
148 BoundMethodHandle rebind() {
149 return BoundMethodHandle.makeReinvoker(this);
150 }
151
152 @Override
153 MethodHandle copyWith(MethodType mt, LambdaForm lf) {
154 assert(this.getClass() == DirectMethodHandle.class); // must override in subclasses
155 return new DirectMethodHandle(mt, lf, member, crackable);
156 }
157
158 @Override
159 MethodHandle viewAsType(MethodType newType, boolean strict) {
521 /*non-public*/
522 static long fieldOffset(Object accessorObj) {
523 // Note: We return a long because that is what Unsafe.getObject likes.
524 // We store a plain int because it is more compact.
525 return ((Accessor)accessorObj).fieldOffset;
526 }
527
528 @ForceInline
529 /*non-public*/
530 static Object checkBase(Object obj) {
531 // Note that the object's class has already been verified,
532 // since the parameter type of the Accessor method handle
533 // is either member.getDeclaringClass or a subclass.
534 // This was verified in DirectMethodHandle.make.
535 // Therefore, the only remaining check is for null.
536 // Since this check is *not* guaranteed by Unsafe.getInt
537 // and its siblings, we need to make an explicit one here.
538 return Objects.requireNonNull(obj);
539 }
540
541 /** This subclass handles static field references. */
542 static class StaticAccessor extends DirectMethodHandle {
543 private final Class<?> fieldType;
544 private final Object staticBase;
545 private final long staticOffset;
546
547 private StaticAccessor(MethodType mtype, LambdaForm form, MemberName member,
548 boolean crackable, Object staticBase, long staticOffset) {
549 super(mtype, form, member, crackable);
550 this.fieldType = member.getFieldType();
551 this.staticBase = staticBase;
552 this.staticOffset = staticOffset;
553 }
554
555 @Override Object checkCast(Object obj) {
556 return fieldType.cast(obj);
557 }
558 @Override
559 MethodHandle copyWith(MethodType mt, LambdaForm lf) {
560 return new StaticAccessor(mt, lf, member, crackable, staticBase, staticOffset);
561 }
562 @Override
563 MethodHandle viewAsType(MethodType newType, boolean strict) {
564 assert(viewAsTypeChecks(newType, strict));
565 return new StaticAccessor(newType, form, member, false, staticBase, staticOffset);
573 }
574
575 @ForceInline
576 /*non-public*/
577 static Object staticBase(Object accessorObj) {
578 return ((StaticAccessor)accessorObj).staticBase;
579 }
580
581 @ForceInline
582 /*non-public*/
583 static long staticOffset(Object accessorObj) {
584 return ((StaticAccessor)accessorObj).staticOffset;
585 }
586
587 @ForceInline
588 /*non-public*/
589 static Object checkCast(Object mh, Object obj) {
590 return ((DirectMethodHandle) mh).checkCast(obj);
591 }
592
593 Object checkCast(Object obj) {
594 return member.getReturnType().cast(obj);
595 }
596
597 // Caching machinery for field accessors:
598 static final byte
599 AF_GETFIELD = 0,
600 AF_PUTFIELD = 1,
601 AF_GETSTATIC = 2,
602 AF_PUTSTATIC = 3,
603 AF_GETSTATIC_INIT = 4,
604 AF_PUTSTATIC_INIT = 5,
605 AF_LIMIT = 6;
606 // Enumerate the different field kinds using Wrapper,
607 // with an extra case added for checked references.
608 static final int
609 FT_LAST_WRAPPER = Wrapper.COUNT-1,
610 FT_UNCHECKED_REF = Wrapper.OBJECT.ordinal(),
611 FT_CHECKED_REF = FT_LAST_WRAPPER+1,
612 FT_LIMIT = FT_LAST_WRAPPER+2;
613 private static int afIndex(byte formOp, boolean isVolatile, int ftypeKind) {
614 return ((formOp * FT_LIMIT * 2)
615 + (isVolatile ? FT_LIMIT : 0)
616 + ftypeKind);
617 }
618 @Stable
619 private static final LambdaForm[] ACCESSOR_FORMS
620 = new LambdaForm[afIndex(AF_LIMIT, false, 0)];
621 static int ftypeKind(Class<?> ftype) {
622 if (ftype.isPrimitive())
623 return Wrapper.forPrimitiveType(ftype).ordinal();
624 else if (VerifyType.isNullReferenceConversion(Object.class, ftype))
625 return FT_UNCHECKED_REF;
626 else
627 return FT_CHECKED_REF;
628 }
629
630 /**
631 * Create a LF which can access the given field.
632 * Cache and share this structure among all fields with
633 * the same basicType and refKind.
634 */
635 private static LambdaForm preparedFieldLambdaForm(MemberName m) {
636 Class<?> ftype = m.getFieldType();
637 boolean isVolatile = m.isVolatile();
638 byte formOp = switch (m.getReferenceKind()) {
639 case REF_getField -> AF_GETFIELD;
640 case REF_putField -> AF_PUTFIELD;
641 case REF_getStatic -> AF_GETSTATIC;
642 case REF_putStatic -> AF_PUTSTATIC;
643 default -> throw new InternalError(m.toString());
644 };
645 if (shouldBeInitialized(m)) {
646 // precompute the barrier-free version:
647 preparedFieldLambdaForm(formOp, isVolatile, ftype);
648 assert((AF_GETSTATIC_INIT - AF_GETSTATIC) ==
649 (AF_PUTSTATIC_INIT - AF_PUTSTATIC));
650 formOp += (AF_GETSTATIC_INIT - AF_GETSTATIC);
651 }
652 LambdaForm lform = preparedFieldLambdaForm(formOp, isVolatile, ftype);
653 maybeCompile(lform, m);
654 assert(lform.methodType().dropParameterTypes(0, 1)
655 .equals(m.getInvocationType().basicType()))
656 : Arrays.asList(m, m.getInvocationType().basicType(), lform, lform.methodType());
657 return lform;
658 }
659 private static LambdaForm preparedFieldLambdaForm(byte formOp, boolean isVolatile, Class<?> ftype) {
660 int ftypeKind = ftypeKind(ftype);
661 int afIndex = afIndex(formOp, isVolatile, ftypeKind);
662 LambdaForm lform = ACCESSOR_FORMS[afIndex];
663 if (lform != null) return lform;
664 lform = makePreparedFieldLambdaForm(formOp, isVolatile, ftypeKind);
665 ACCESSOR_FORMS[afIndex] = lform; // don't bother with a CAS
666 return lform;
667 }
668
669 private static final Wrapper[] ALL_WRAPPERS = Wrapper.values();
670
671 private static Kind getFieldKind(boolean isGetter, boolean isVolatile, Wrapper wrapper) {
672 if (isGetter) {
673 if (isVolatile) {
674 switch (wrapper) {
675 case BOOLEAN: return GET_BOOLEAN_VOLATILE;
676 case BYTE: return GET_BYTE_VOLATILE;
677 case SHORT: return GET_SHORT_VOLATILE;
678 case CHAR: return GET_CHAR_VOLATILE;
679 case INT: return GET_INT_VOLATILE;
680 case LONG: return GET_LONG_VOLATILE;
681 case FLOAT: return GET_FLOAT_VOLATILE;
682 case DOUBLE: return GET_DOUBLE_VOLATILE;
683 case OBJECT: return GET_REFERENCE_VOLATILE;
684 }
685 } else {
686 switch (wrapper) {
687 case BOOLEAN: return GET_BOOLEAN;
688 case BYTE: return GET_BYTE;
689 case SHORT: return GET_SHORT;
690 case CHAR: return GET_CHAR;
691 case INT: return GET_INT;
692 case LONG: return GET_LONG;
693 case FLOAT: return GET_FLOAT;
694 case DOUBLE: return GET_DOUBLE;
695 case OBJECT: return GET_REFERENCE;
696 }
697 }
698 } else {
699 if (isVolatile) {
700 switch (wrapper) {
701 case BOOLEAN: return PUT_BOOLEAN_VOLATILE;
702 case BYTE: return PUT_BYTE_VOLATILE;
703 case SHORT: return PUT_SHORT_VOLATILE;
704 case CHAR: return PUT_CHAR_VOLATILE;
705 case INT: return PUT_INT_VOLATILE;
706 case LONG: return PUT_LONG_VOLATILE;
707 case FLOAT: return PUT_FLOAT_VOLATILE;
708 case DOUBLE: return PUT_DOUBLE_VOLATILE;
709 case OBJECT: return PUT_REFERENCE_VOLATILE;
710 }
711 } else {
712 switch (wrapper) {
713 case BOOLEAN: return PUT_BOOLEAN;
714 case BYTE: return PUT_BYTE;
715 case SHORT: return PUT_SHORT;
716 case CHAR: return PUT_CHAR;
717 case INT: return PUT_INT;
718 case LONG: return PUT_LONG;
719 case FLOAT: return PUT_FLOAT;
720 case DOUBLE: return PUT_DOUBLE;
721 case OBJECT: return PUT_REFERENCE;
722 }
723 }
724 }
725 throw new AssertionError("Invalid arguments");
726 }
727
728 static LambdaForm makePreparedFieldLambdaForm(byte formOp, boolean isVolatile, int ftypeKind) {
729 boolean isGetter = (formOp & 1) == (AF_GETFIELD & 1);
730 boolean isStatic = (formOp >= AF_GETSTATIC);
731 boolean needsInit = (formOp >= AF_GETSTATIC_INIT);
732 boolean needsCast = (ftypeKind == FT_CHECKED_REF);
733 Wrapper fw = (needsCast ? Wrapper.OBJECT : ALL_WRAPPERS[ftypeKind]);
734 Class<?> ft = fw.primitiveType();
735 assert(ftypeKind(needsCast ? String.class : ft) == ftypeKind);
736
737 // getObject, putIntVolatile, etc.
738 Kind kind = getFieldKind(isGetter, isVolatile, fw);
739
740 MethodType linkerType;
741 if (isGetter)
742 linkerType = MethodType.methodType(ft, Object.class, long.class);
743 else
744 linkerType = MethodType.methodType(void.class, Object.class, long.class, ft);
745 MemberName linker = new MemberName(Unsafe.class, kind.methodName, linkerType, REF_invokeVirtual);
746 try {
747 linker = IMPL_NAMES.resolveOrFail(REF_invokeVirtual, linker, null, LM_TRUSTED,
748 NoSuchMethodException.class);
749 } catch (ReflectiveOperationException ex) {
750 throw newInternalError(ex);
751 }
752
753 // What is the external type of the lambda form?
754 MethodType mtype;
755 if (isGetter)
756 mtype = MethodType.methodType(ft);
757 else
758 mtype = MethodType.methodType(void.class, ft);
759 mtype = mtype.basicType(); // erase short to int, etc.
760 if (!isStatic)
761 mtype = mtype.insertParameterTypes(0, Object.class);
762 final int DMH_THIS = 0;
763 final int ARG_BASE = 1;
764 final int ARG_LIMIT = ARG_BASE + mtype.parameterCount();
765 // if this is for non-static access, the base pointer is stored at this index:
766 final int OBJ_BASE = isStatic ? -1 : ARG_BASE;
767 // if this is for write access, the value to be written is stored at this index:
768 final int SET_VALUE = isGetter ? -1 : ARG_LIMIT - 1;
769 int nameCursor = ARG_LIMIT;
770 final int F_HOLDER = (isStatic ? nameCursor++ : -1); // static base if any
771 final int F_OFFSET = nameCursor++; // Either static offset or field offset.
772 final int OBJ_CHECK = (OBJ_BASE >= 0 ? nameCursor++ : -1);
773 final int U_HOLDER = nameCursor++; // UNSAFE holder
774 final int INIT_BAR = (needsInit ? nameCursor++ : -1);
775 final int PRE_CAST = (needsCast && !isGetter ? nameCursor++ : -1);
776 final int LINKER_CALL = nameCursor++;
777 final int POST_CAST = (needsCast && isGetter ? nameCursor++ : -1);
778 final int RESULT = nameCursor-1; // either the call or the cast
779 Name[] names = arguments(nameCursor - ARG_LIMIT, mtype.invokerType());
780 if (needsInit)
781 names[INIT_BAR] = new Name(getFunction(NF_ensureInitialized), names[DMH_THIS]);
782 if (needsCast && !isGetter)
783 names[PRE_CAST] = new Name(getFunction(NF_checkCast), names[DMH_THIS], names[SET_VALUE]);
784 Object[] outArgs = new Object[1 + linkerType.parameterCount()];
785 assert(outArgs.length == (isGetter ? 3 : 4));
786 outArgs[0] = names[U_HOLDER] = new Name(getFunction(NF_UNSAFE));
787 if (isStatic) {
788 outArgs[1] = names[F_HOLDER] = new Name(getFunction(NF_staticBase), names[DMH_THIS]);
789 outArgs[2] = names[F_OFFSET] = new Name(getFunction(NF_staticOffset), names[DMH_THIS]);
790 } else {
791 outArgs[1] = names[OBJ_CHECK] = new Name(getFunction(NF_checkBase), names[OBJ_BASE]);
792 outArgs[2] = names[F_OFFSET] = new Name(getFunction(NF_fieldOffset), names[DMH_THIS]);
793 }
794 if (!isGetter) {
795 outArgs[3] = (needsCast ? names[PRE_CAST] : names[SET_VALUE]);
796 }
797 for (Object a : outArgs) assert(a != null);
798 names[LINKER_CALL] = new Name(linker, outArgs);
799 if (needsCast && isGetter)
800 names[POST_CAST] = new Name(getFunction(NF_checkCast), names[DMH_THIS], names[LINKER_CALL]);
801 for (Name n : names) assert(n != null);
802
803 LambdaForm form;
804 if (needsCast || needsInit) {
805 // can't use the pre-generated form when casting and/or initializing
806 form = new LambdaForm(ARG_LIMIT, names, RESULT);
807 } else {
808 form = new LambdaForm(ARG_LIMIT, names, RESULT, kind);
809 }
810
811 if (LambdaForm.debugNames()) {
812 // add some detail to the lambdaForm debugname,
813 // significant only for debugging
814 StringBuilder nameBuilder = new StringBuilder(kind.methodName);
815 if (isStatic) {
826 LambdaForm.associateWithDebugName(form, nameBuilder.toString());
827 }
828 return form;
829 }
830
831 /**
832 * Pre-initialized NamedFunctions for bootstrapping purposes.
833 */
834 static final byte NF_internalMemberName = 0,
835 NF_internalMemberNameEnsureInit = 1,
836 NF_ensureInitialized = 2,
837 NF_fieldOffset = 3,
838 NF_checkBase = 4,
839 NF_staticBase = 5,
840 NF_staticOffset = 6,
841 NF_checkCast = 7,
842 NF_allocateInstance = 8,
843 NF_constructorMethod = 9,
844 NF_UNSAFE = 10,
845 NF_checkReceiver = 11,
846 NF_LIMIT = 12;
847
848 private static final @Stable NamedFunction[] NFS = new NamedFunction[NF_LIMIT];
849
850 private static NamedFunction getFunction(byte func) {
851 NamedFunction nf = NFS[func];
852 if (nf != null) {
853 return nf;
854 }
855 // Each nf must be statically invocable or we get tied up in our bootstraps.
856 nf = NFS[func] = createFunction(func);
857 assert(InvokerBytecodeGenerator.isStaticallyInvocable(nf));
858 return nf;
859 }
860
861 private static final MethodType OBJ_OBJ_TYPE = MethodType.methodType(Object.class, Object.class);
862
863 private static final MethodType LONG_OBJ_TYPE = MethodType.methodType(long.class, Object.class);
864
865 private static NamedFunction createFunction(byte func) {
866 try {
867 switch (func) {
868 case NF_internalMemberName:
869 return getNamedFunction("internalMemberName", OBJ_OBJ_TYPE);
870 case NF_internalMemberNameEnsureInit:
871 return getNamedFunction("internalMemberNameEnsureInit", OBJ_OBJ_TYPE);
872 case NF_ensureInitialized:
873 return getNamedFunction("ensureInitialized", MethodType.methodType(void.class, Object.class));
874 case NF_fieldOffset:
875 return getNamedFunction("fieldOffset", LONG_OBJ_TYPE);
876 case NF_checkBase:
877 return getNamedFunction("checkBase", OBJ_OBJ_TYPE);
878 case NF_staticBase:
879 return getNamedFunction("staticBase", OBJ_OBJ_TYPE);
880 case NF_staticOffset:
881 return getNamedFunction("staticOffset", LONG_OBJ_TYPE);
882 case NF_checkCast:
883 return getNamedFunction("checkCast", MethodType.methodType(Object.class, Object.class, Object.class));
884 case NF_allocateInstance:
885 return getNamedFunction("allocateInstance", OBJ_OBJ_TYPE);
886 case NF_constructorMethod:
887 return getNamedFunction("constructorMethod", OBJ_OBJ_TYPE);
888 case NF_UNSAFE:
889 MemberName member = new MemberName(MethodHandleStatics.class, "UNSAFE", Unsafe.class, REF_getField);
890 return new NamedFunction(
891 MemberName.getFactory().resolveOrFail(REF_getField, member,
892 DirectMethodHandle.class, LM_TRUSTED,
893 NoSuchMethodException.class));
894 case NF_checkReceiver:
895 member = new MemberName(DirectMethodHandle.class, "checkReceiver", OBJ_OBJ_TYPE, REF_invokeVirtual);
896 return new NamedFunction(
897 MemberName.getFactory().resolveOrFail(REF_invokeVirtual, member,
898 DirectMethodHandle.class, LM_TRUSTED,
899 NoSuchMethodException.class));
900 default:
901 throw newInternalError("Unknown function: " + func);
902 }
903 } catch (ReflectiveOperationException ex) {
904 throw newInternalError(ex);
905 }
906 }
907
908 private static NamedFunction getNamedFunction(String name, MethodType type)
909 throws ReflectiveOperationException
910 {
911 MemberName member = new MemberName(DirectMethodHandle.class, name, type, REF_invokeStatic);
912 return new NamedFunction(
913 MemberName.getFactory().resolveOrFail(REF_invokeStatic, member,
914 DirectMethodHandle.class, LM_TRUSTED,
915 NoSuchMethodException.class));
916 }
917
918 static {
919 // The Holder class will contain pre-generated DirectMethodHandles resolved
|
61 if (member.getDeclaringClass().isInterface() &&
62 member.getReferenceKind() == REF_invokeInterface &&
63 member.isMethod() && !member.isAbstract()) {
64 // Check for corner case: invokeinterface of Object method
65 MemberName m = new MemberName(Object.class, member.getName(), member.getMethodType(), member.getReferenceKind());
66 m = MemberName.getFactory().resolveOrNull(m.getReferenceKind(), m, null, LM_TRUSTED);
67 if (m != null && m.isPublic()) {
68 assert(member.getReferenceKind() == m.getReferenceKind()); // else this.form is wrong
69 member = m;
70 }
71 }
72
73 this.member = member;
74 this.crackable = crackable;
75 }
76
77 // Factory methods:
78 static DirectMethodHandle make(byte refKind, Class<?> refc, MemberName member, Class<?> callerClass) {
79 MethodType mtype = member.getMethodOrFieldType();
80 if (!member.isStatic()) {
81 if (!member.getDeclaringClass().isAssignableFrom(refc) || member.isObjectConstructor())
82 throw new InternalError(member.toString());
83 Class<?> receiverType = refc.isPrimitiveClass() ? refc.asValueType() : refc;
84 mtype = mtype.insertParameterTypes(0, receiverType);
85 }
86 if (!member.isField()) {
87 // refKind reflects the original type of lookup via findSpecial or
88 // findVirtual etc.
89 return switch (refKind) {
90 case REF_invokeSpecial -> {
91 member = member.asSpecial();
92 // if caller is an interface we need to adapt to get the
93 // receiver check inserted
94 if (callerClass == null) {
95 throw new InternalError("callerClass must not be null for REF_invokeSpecial");
96 }
97 LambdaForm lform = preparedLambdaForm(member, callerClass.isInterface());
98 yield new Special(mtype, lform, member, true, callerClass);
99 }
100 case REF_invokeInterface -> {
101 // for interfaces we always need the receiver typecheck,
102 // so we always pass 'true' to ensure we adapt if needed
103 // to include the REF_invokeSpecial case
104 LambdaForm lform = preparedLambdaForm(member, true);
112 } else {
113 LambdaForm lform = preparedFieldLambdaForm(member);
114 if (member.isStatic()) {
115 long offset = MethodHandleNatives.staticFieldOffset(member);
116 Object base = MethodHandleNatives.staticFieldBase(member);
117 return new StaticAccessor(mtype, lform, member, true, base, offset);
118 } else {
119 long offset = MethodHandleNatives.objectFieldOffset(member);
120 assert(offset == (int)offset);
121 return new Accessor(mtype, lform, member, true, (int)offset);
122 }
123 }
124 }
125 static DirectMethodHandle make(Class<?> refc, MemberName member) {
126 byte refKind = member.getReferenceKind();
127 if (refKind == REF_invokeSpecial)
128 refKind = REF_invokeVirtual;
129 return make(refKind, refc, member, null /* no callerClass context */);
130 }
131 static DirectMethodHandle make(MemberName member) {
132 if (member.isObjectConstructor() && member.getReturnType() == void.class)
133 return makeAllocator(member);
134 return make(member.getDeclaringClass(), member);
135 }
136 private static DirectMethodHandle makeAllocator(MemberName ctor) {
137 assert(ctor.isObjectConstructor() && !ctor.getDeclaringClass().isPrimitiveClass()) : ctor;
138
139 Class<?> instanceClass = ctor.getDeclaringClass();
140 ctor = ctor.asObjectConstructor();
141 assert(ctor.getReferenceKind() == REF_newInvokeSpecial) : ctor;
142 MethodType mtype = ctor.getMethodType().changeReturnType(instanceClass);
143 LambdaForm lform = preparedLambdaForm(ctor);
144 MemberName init = ctor.asSpecial();
145 assert(init.getMethodType().returnType() == void.class);
146 return new Constructor(mtype, lform, ctor, true, init, instanceClass);
147 }
148
149 @Override
150 BoundMethodHandle rebind() {
151 return BoundMethodHandle.makeReinvoker(this);
152 }
153
154 @Override
155 MethodHandle copyWith(MethodType mt, LambdaForm lf) {
156 assert(this.getClass() == DirectMethodHandle.class); // must override in subclasses
157 return new DirectMethodHandle(mt, lf, member, crackable);
158 }
159
160 @Override
161 MethodHandle viewAsType(MethodType newType, boolean strict) {
523 /*non-public*/
524 static long fieldOffset(Object accessorObj) {
525 // Note: We return a long because that is what Unsafe.getObject likes.
526 // We store a plain int because it is more compact.
527 return ((Accessor)accessorObj).fieldOffset;
528 }
529
530 @ForceInline
531 /*non-public*/
532 static Object checkBase(Object obj) {
533 // Note that the object's class has already been verified,
534 // since the parameter type of the Accessor method handle
535 // is either member.getDeclaringClass or a subclass.
536 // This was verified in DirectMethodHandle.make.
537 // Therefore, the only remaining check is for null.
538 // Since this check is *not* guaranteed by Unsafe.getInt
539 // and its siblings, we need to make an explicit one here.
540 return Objects.requireNonNull(obj);
541 }
542
543 static class StaticAccessor extends DirectMethodHandle {
544 final Class<?> fieldType;
545 final Object staticBase;
546 final long staticOffset;
547
548 private StaticAccessor(MethodType mtype, LambdaForm form, MemberName member,
549 boolean crackable, Object staticBase, long staticOffset) {
550 super(mtype, form, member, crackable);
551 this.fieldType = member.getFieldType();
552 this.staticBase = staticBase;
553 this.staticOffset = staticOffset;
554 }
555
556 @Override Object checkCast(Object obj) {
557 return fieldType.cast(obj);
558 }
559 @Override
560 MethodHandle copyWith(MethodType mt, LambdaForm lf) {
561 return new StaticAccessor(mt, lf, member, crackable, staticBase, staticOffset);
562 }
563 @Override
564 MethodHandle viewAsType(MethodType newType, boolean strict) {
565 assert(viewAsTypeChecks(newType, strict));
566 return new StaticAccessor(newType, form, member, false, staticBase, staticOffset);
574 }
575
576 @ForceInline
577 /*non-public*/
578 static Object staticBase(Object accessorObj) {
579 return ((StaticAccessor)accessorObj).staticBase;
580 }
581
582 @ForceInline
583 /*non-public*/
584 static long staticOffset(Object accessorObj) {
585 return ((StaticAccessor)accessorObj).staticOffset;
586 }
587
588 @ForceInline
589 /*non-public*/
590 static Object checkCast(Object mh, Object obj) {
591 return ((DirectMethodHandle) mh).checkCast(obj);
592 }
593
594 @ForceInline
595 /*non-public*/ static Class<?> fieldType(Object accessorObj) {
596 return ((Accessor) accessorObj).fieldType;
597 }
598
599 @ForceInline
600 /*non-public*/ static Class<?> staticFieldType(Object accessorObj) {
601 return ((StaticAccessor) accessorObj).fieldType;
602 }
603
604 Object checkCast(Object obj) {
605 return member.getReturnType().cast(obj);
606 }
607
608 // Caching machinery for field accessors:
609 static final byte
610 AF_GETFIELD = 0,
611 AF_PUTFIELD = 1,
612 AF_GETSTATIC = 2,
613 AF_PUTSTATIC = 3,
614 AF_GETSTATIC_INIT = 4,
615 AF_PUTSTATIC_INIT = 5,
616 AF_LIMIT = 6;
617 // Enumerate the different field kinds using Wrapper,
618 // with an extra case added for checked references and value field access
619 static final int
620 FT_LAST_WRAPPER = Wrapper.COUNT-1,
621 FT_UNCHECKED_REF = Wrapper.OBJECT.ordinal(),
622 FT_CHECKED_REF = FT_LAST_WRAPPER+1,
623 FT_CHECKED_VALUE = FT_LAST_WRAPPER+2, // flattened and non-flattened
624 FT_LIMIT = FT_LAST_WRAPPER+4;
625 private static int afIndex(byte formOp, boolean isVolatile, boolean isFlatValue, int ftypeKind) {
626 return ((formOp * FT_LIMIT * 2)
627 + (isVolatile ? FT_LIMIT : 0)
628 + (isFlatValue ? 1 : 0)
629 + ftypeKind);
630 }
631 @Stable
632 private static final LambdaForm[] ACCESSOR_FORMS
633 = new LambdaForm[afIndex(AF_LIMIT, false, false, 0)];
634 static int ftypeKind(Class<?> ftype, boolean isValue) {
635 if (ftype.isPrimitive())
636 return Wrapper.forPrimitiveType(ftype).ordinal();
637 else if (VerifyType.isNullReferenceConversion(Object.class, ftype)) {
638 return FT_UNCHECKED_REF;
639 } else
640 // null check for value type in addition to check cast
641 return isValue ? FT_CHECKED_VALUE : FT_CHECKED_REF;
642 }
643
644 /**
645 * Create a LF which can access the given field.
646 * Cache and share this structure among all fields with
647 * the same basicType and refKind.
648 */
649 private static LambdaForm preparedFieldLambdaForm(MemberName m) {
650 Class<?> ftype = m.getFieldType();
651 boolean isVolatile = m.isVolatile();
652 byte formOp = switch (m.getReferenceKind()) {
653 case REF_getField -> AF_GETFIELD;
654 case REF_putField -> AF_PUTFIELD;
655 case REF_getStatic -> AF_GETSTATIC;
656 case REF_putStatic -> AF_PUTSTATIC;
657 default -> throw new InternalError(m.toString());
658 };
659 if (shouldBeInitialized(m)) {
660 // precompute the barrier-free version:
661 preparedFieldLambdaForm(formOp, m.isVolatile(), m.isInlineableField(), m.isFlattened(), ftype);
662 assert((AF_GETSTATIC_INIT - AF_GETSTATIC) ==
663 (AF_PUTSTATIC_INIT - AF_PUTSTATIC));
664 formOp += (AF_GETSTATIC_INIT - AF_GETSTATIC);
665 }
666 LambdaForm lform = preparedFieldLambdaForm(formOp, m.isVolatile(), m.isInlineableField(), m.isFlattened(), ftype);
667 maybeCompile(lform, m);
668 assert(lform.methodType().dropParameterTypes(0, 1)
669 .equals(m.getInvocationType().basicType()))
670 : Arrays.asList(m, m.getInvocationType().basicType(), lform, lform.methodType());
671 return lform;
672 }
673
674 private static LambdaForm preparedFieldLambdaForm(byte formOp, boolean isVolatile, boolean isValue, boolean isFlatValue, Class<?> ftype) {
675 int ftypeKind = ftypeKind(ftype, isValue);
676 int afIndex = afIndex(formOp, isVolatile, isFlatValue, ftypeKind);
677 LambdaForm lform = ACCESSOR_FORMS[afIndex];
678 if (lform != null) return lform;
679 lform = makePreparedFieldLambdaForm(formOp, isVolatile, isValue, isFlatValue, ftypeKind);
680 ACCESSOR_FORMS[afIndex] = lform; // don't bother with a CAS
681 return lform;
682 }
683
684 private static final Wrapper[] ALL_WRAPPERS = Wrapper.values();
685
686 private static Kind getFieldKind(boolean isGetter, boolean isVolatile, boolean isFlatValue, Wrapper wrapper) {
687 if (isGetter) {
688 if (isVolatile) {
689 switch (wrapper) {
690 case BOOLEAN: return GET_BOOLEAN_VOLATILE;
691 case BYTE: return GET_BYTE_VOLATILE;
692 case SHORT: return GET_SHORT_VOLATILE;
693 case CHAR: return GET_CHAR_VOLATILE;
694 case INT: return GET_INT_VOLATILE;
695 case LONG: return GET_LONG_VOLATILE;
696 case FLOAT: return GET_FLOAT_VOLATILE;
697 case DOUBLE: return GET_DOUBLE_VOLATILE;
698 case OBJECT: return isFlatValue ? GET_VALUE_VOLATILE : GET_REFERENCE_VOLATILE;
699 }
700 } else {
701 switch (wrapper) {
702 case BOOLEAN: return GET_BOOLEAN;
703 case BYTE: return GET_BYTE;
704 case SHORT: return GET_SHORT;
705 case CHAR: return GET_CHAR;
706 case INT: return GET_INT;
707 case LONG: return GET_LONG;
708 case FLOAT: return GET_FLOAT;
709 case DOUBLE: return GET_DOUBLE;
710 case OBJECT: return isFlatValue ? GET_VALUE : GET_REFERENCE;
711 }
712 }
713 } else {
714 if (isVolatile) {
715 switch (wrapper) {
716 case BOOLEAN: return PUT_BOOLEAN_VOLATILE;
717 case BYTE: return PUT_BYTE_VOLATILE;
718 case SHORT: return PUT_SHORT_VOLATILE;
719 case CHAR: return PUT_CHAR_VOLATILE;
720 case INT: return PUT_INT_VOLATILE;
721 case LONG: return PUT_LONG_VOLATILE;
722 case FLOAT: return PUT_FLOAT_VOLATILE;
723 case DOUBLE: return PUT_DOUBLE_VOLATILE;
724 case OBJECT: return isFlatValue ? PUT_VALUE_VOLATILE : PUT_REFERENCE_VOLATILE;
725 }
726 } else {
727 switch (wrapper) {
728 case BOOLEAN: return PUT_BOOLEAN;
729 case BYTE: return PUT_BYTE;
730 case SHORT: return PUT_SHORT;
731 case CHAR: return PUT_CHAR;
732 case INT: return PUT_INT;
733 case LONG: return PUT_LONG;
734 case FLOAT: return PUT_FLOAT;
735 case DOUBLE: return PUT_DOUBLE;
736 case OBJECT: return isFlatValue ? PUT_VALUE : PUT_REFERENCE;
737 }
738 }
739 }
740 throw new AssertionError("Invalid arguments");
741 }
742
743 /** invoked by GenerateJLIClassesHelper */
744 static LambdaForm makePreparedFieldLambdaForm(byte formOp, boolean isVolatile, int ftype) {
745 return makePreparedFieldLambdaForm(formOp, isVolatile, false, false, ftype);
746 }
747
748 private static LambdaForm makePreparedFieldLambdaForm(byte formOp, boolean isVolatile, boolean isValue, boolean isFlatValue, int ftypeKind) {
749 boolean isGetter = (formOp & 1) == (AF_GETFIELD & 1);
750 boolean isStatic = (formOp >= AF_GETSTATIC);
751 boolean needsInit = (formOp >= AF_GETSTATIC_INIT);
752 boolean needsCast = (ftypeKind == FT_CHECKED_REF || ftypeKind == FT_CHECKED_VALUE);
753 Wrapper fw = (needsCast ? Wrapper.OBJECT : ALL_WRAPPERS[ftypeKind]);
754 Class<?> ft = fw.primitiveType();
755 assert(needsCast ? true : ftypeKind(ft, isValue) == ftypeKind);
756
757 // getObject, putIntVolatile, etc.
758 Kind kind = getFieldKind(isGetter, isVolatile, isFlatValue, fw);
759
760 MethodType linkerType;
761 boolean hasValueTypeArg = isGetter ? isValue : isFlatValue;
762 if (isGetter) {
763 linkerType = isValue ? MethodType.methodType(ft, Object.class, long.class, Class.class)
764 : MethodType.methodType(ft, Object.class, long.class);
765 } else {
766 linkerType = isFlatValue ? MethodType.methodType(void.class, Object.class, long.class, Class.class, ft)
767 : MethodType.methodType(void.class, Object.class, long.class, ft);
768 }
769 MemberName linker = new MemberName(Unsafe.class, kind.methodName, linkerType, REF_invokeVirtual);
770 try {
771 linker = IMPL_NAMES.resolveOrFail(REF_invokeVirtual, linker, null, LM_TRUSTED,
772 NoSuchMethodException.class);
773 } catch (ReflectiveOperationException ex) {
774 throw newInternalError(ex);
775 }
776
777 // What is the external type of the lambda form?
778 MethodType mtype;
779 if (isGetter)
780 mtype = MethodType.methodType(ft);
781 else
782 mtype = MethodType.methodType(void.class, ft);
783 mtype = mtype.basicType(); // erase short to int, etc.
784 if (!isStatic)
785 mtype = mtype.insertParameterTypes(0, Object.class);
786 final int DMH_THIS = 0;
787 final int ARG_BASE = 1;
788 final int ARG_LIMIT = ARG_BASE + mtype.parameterCount();
789 // if this is for non-static access, the base pointer is stored at this index:
790 final int OBJ_BASE = isStatic ? -1 : ARG_BASE;
791 // if this is for write access, the value to be written is stored at this index:
792 final int SET_VALUE = isGetter ? -1 : ARG_LIMIT - 1;
793 int nameCursor = ARG_LIMIT;
794 final int F_HOLDER = (isStatic ? nameCursor++ : -1); // static base if any
795 final int F_OFFSET = nameCursor++; // Either static offset or field offset.
796 final int OBJ_CHECK = (OBJ_BASE >= 0 ? nameCursor++ : -1);
797 final int U_HOLDER = nameCursor++; // UNSAFE holder
798 final int INIT_BAR = (needsInit ? nameCursor++ : -1);
799 final int VALUE_TYPE = (hasValueTypeArg ? nameCursor++ : -1);
800 final int PRE_CAST = (needsCast && !isGetter ? nameCursor++ : -1);
801 final int LINKER_CALL = nameCursor++;
802 final int POST_CAST = (needsCast && isGetter ? nameCursor++ : -1);
803 final int RESULT = nameCursor-1; // either the call or the cast
804 Name[] names = arguments(nameCursor - ARG_LIMIT, mtype.invokerType());
805 if (needsInit)
806 names[INIT_BAR] = new Name(getFunction(NF_ensureInitialized), names[DMH_THIS]);
807 if (needsCast && !isGetter)
808 names[PRE_CAST] = new Name(getFunction(NF_checkCast), names[DMH_THIS], names[SET_VALUE]);
809 Object[] outArgs = new Object[1 + linkerType.parameterCount()];
810 assert (outArgs.length == (isGetter ? 3 : 4) + (hasValueTypeArg ? 1 : 0));
811 outArgs[0] = names[U_HOLDER] = new Name(getFunction(NF_UNSAFE));
812 if (isStatic) {
813 outArgs[1] = names[F_HOLDER] = new Name(getFunction(NF_staticBase), names[DMH_THIS]);
814 outArgs[2] = names[F_OFFSET] = new Name(getFunction(NF_staticOffset), names[DMH_THIS]);
815 } else {
816 outArgs[1] = names[OBJ_CHECK] = new Name(getFunction(NF_checkBase), names[OBJ_BASE]);
817 outArgs[2] = names[F_OFFSET] = new Name(getFunction(NF_fieldOffset), names[DMH_THIS]);
818 }
819 int x = 3;
820 if (hasValueTypeArg) {
821 outArgs[x++] = names[VALUE_TYPE] = isStatic ? new Name(getFunction(NF_staticFieldType), names[DMH_THIS])
822 : new Name(getFunction(NF_fieldType), names[DMH_THIS]);
823 }
824 if (!isGetter) {
825 outArgs[x] = (needsCast ? names[PRE_CAST] : names[SET_VALUE]);
826 }
827 for (Object a : outArgs) assert(a != null);
828 names[LINKER_CALL] = new Name(linker, outArgs);
829 if (needsCast && isGetter)
830 names[POST_CAST] = new Name(getFunction(NF_checkCast), names[DMH_THIS], names[LINKER_CALL]);
831 for (Name n : names) assert(n != null);
832
833 LambdaForm form;
834 if (needsCast || needsInit) {
835 // can't use the pre-generated form when casting and/or initializing
836 form = new LambdaForm(ARG_LIMIT, names, RESULT);
837 } else {
838 form = new LambdaForm(ARG_LIMIT, names, RESULT, kind);
839 }
840
841 if (LambdaForm.debugNames()) {
842 // add some detail to the lambdaForm debugname,
843 // significant only for debugging
844 StringBuilder nameBuilder = new StringBuilder(kind.methodName);
845 if (isStatic) {
856 LambdaForm.associateWithDebugName(form, nameBuilder.toString());
857 }
858 return form;
859 }
860
861 /**
862 * Pre-initialized NamedFunctions for bootstrapping purposes.
863 */
864 static final byte NF_internalMemberName = 0,
865 NF_internalMemberNameEnsureInit = 1,
866 NF_ensureInitialized = 2,
867 NF_fieldOffset = 3,
868 NF_checkBase = 4,
869 NF_staticBase = 5,
870 NF_staticOffset = 6,
871 NF_checkCast = 7,
872 NF_allocateInstance = 8,
873 NF_constructorMethod = 9,
874 NF_UNSAFE = 10,
875 NF_checkReceiver = 11,
876 NF_fieldType = 12,
877 NF_staticFieldType = 13,
878 NF_LIMIT = 14;
879
880 private static final @Stable NamedFunction[] NFS = new NamedFunction[NF_LIMIT];
881
882 private static NamedFunction getFunction(byte func) {
883 NamedFunction nf = NFS[func];
884 if (nf != null) {
885 return nf;
886 }
887 // Each nf must be statically invocable or we get tied up in our bootstraps.
888 nf = NFS[func] = createFunction(func);
889 assert(InvokerBytecodeGenerator.isStaticallyInvocable(nf));
890 return nf;
891 }
892
893 private static final MethodType CLS_OBJ_TYPE = MethodType.methodType(Class.class, Object.class);
894
895 private static final MethodType OBJ_OBJ_TYPE = MethodType.methodType(Object.class, Object.class);
896
897 private static final MethodType LONG_OBJ_TYPE = MethodType.methodType(long.class, Object.class);
898
899 private static NamedFunction createFunction(byte func) {
900 try {
901 switch (func) {
902 case NF_internalMemberName:
903 return getNamedFunction("internalMemberName", OBJ_OBJ_TYPE);
904 case NF_internalMemberNameEnsureInit:
905 return getNamedFunction("internalMemberNameEnsureInit", OBJ_OBJ_TYPE);
906 case NF_ensureInitialized:
907 return getNamedFunction("ensureInitialized", MethodType.methodType(void.class, Object.class));
908 case NF_fieldOffset:
909 return getNamedFunction("fieldOffset", LONG_OBJ_TYPE);
910 case NF_checkBase:
911 return getNamedFunction("checkBase", OBJ_OBJ_TYPE);
912 case NF_staticBase:
913 return getNamedFunction("staticBase", OBJ_OBJ_TYPE);
914 case NF_staticOffset:
915 return getNamedFunction("staticOffset", LONG_OBJ_TYPE);
916 case NF_checkCast:
917 return getNamedFunction("checkCast", MethodType.methodType(Object.class, Object.class, Object.class));
918 case NF_allocateInstance:
919 return getNamedFunction("allocateInstance", OBJ_OBJ_TYPE);
920 case NF_constructorMethod:
921 return getNamedFunction("constructorMethod", OBJ_OBJ_TYPE);
922 case NF_UNSAFE:
923 MemberName member = new MemberName(MethodHandleStatics.class, "UNSAFE", Unsafe.class, REF_getField);
924 return new NamedFunction(
925 MemberName.getFactory().resolveOrFail(REF_getField, member,
926 DirectMethodHandle.class, LM_TRUSTED,
927 NoSuchMethodException.class));
928 case NF_checkReceiver:
929 member = new MemberName(DirectMethodHandle.class, "checkReceiver", OBJ_OBJ_TYPE, REF_invokeVirtual);
930 return new NamedFunction(
931 MemberName.getFactory().resolveOrFail(REF_invokeVirtual, member,
932 DirectMethodHandle.class, LM_TRUSTED,
933 NoSuchMethodException.class));
934 case NF_fieldType:
935 return getNamedFunction("fieldType", CLS_OBJ_TYPE);
936 case NF_staticFieldType:
937 return getNamedFunction("staticFieldType", CLS_OBJ_TYPE);
938 default:
939 throw newInternalError("Unknown function: " + func);
940 }
941 } catch (ReflectiveOperationException ex) {
942 throw newInternalError(ex);
943 }
944 }
945
946 private static NamedFunction getNamedFunction(String name, MethodType type)
947 throws ReflectiveOperationException
948 {
949 MemberName member = new MemberName(DirectMethodHandle.class, name, type, REF_invokeStatic);
950 return new NamedFunction(
951 MemberName.getFactory().resolveOrFail(REF_invokeStatic, member,
952 DirectMethodHandle.class, LM_TRUSTED,
953 NoSuchMethodException.class));
954 }
955
956 static {
957 // The Holder class will contain pre-generated DirectMethodHandles resolved
|