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package com.oracle.truffle.llvm.runtime.pointer;

import com.oracle.truffle.llvm.runtime.interop.access.LLVMInteropType;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMNode;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMTypes;

Represents a pointer to a managed object on the Java heap. Managed pointers consist of a base object and an offset. Important: Java type checks or cast for the pointer interface types will not work because all interfaces are implemented by a single implementation class for efficiency reasons. Use the static methods isInstance and cast instead. All nodes that use specializations on pointer interfaces need to extend from LLVMNode, or at least use the LLVMTypes type system. /**
 * Represents a pointer to a managed object on the Java heap. Managed pointers consist of a
 * {@link #getObject base object} and an {@link #getOffset offset}.
 *
 * Important: Java type checks or cast for the pointer interface types will not work because all
 * interfaces are implemented by a single implementation class for efficiency reasons. Use the
 * static methods {@link #isInstance} and {@link #cast} instead.
 *
 * All nodes that use specializations on pointer interfaces need to extend from {@link LLVMNode}, or
 * at least use the {@link LLVMTypes} type system.
 */
public interface LLVMManagedPointer extends LLVMPointer {

    
Get the managed object that is the base of this pointer. This is guaranteed to be non-null.
/**
     * Get the managed object that is the base of this pointer. This is guaranteed to be non-null.
     */
    Object getObject();

    
Get the offset into the base object.
/**
     * Get the offset into the base object.
     */
    long getOffset();

    @Override
    LLVMManagedPointer copy();

    @Override
    @Deprecated
    @SuppressWarnings("deprecation")
    boolean equals(Object obj);

    
Increment this pointer. The result has the same base object, and the offset is incremented. The export type of the result pointer is reset to null. /**
     * Increment this pointer. The result has the same {@link #getObject base object}, and the
     * {@link #getOffset offset} is incremented.
     *
     * The {@link #getExportType export type} of the result pointer is reset to {@code null}.
     */
    @Override
    LLVMManagedPointer increment(long offset);

    @Override
    LLVMManagedPointer export(LLVMInteropType newType);

    
Create a new managed pointer, pointing to the beginning of a managed object.
/**
     * Create a new managed pointer, pointing to the beginning of a managed object.
     */
    static LLVMManagedPointer create(Object object) {
        return create(object, 0L);
    }

    
Create a new managed pointer, pointing to a particular offset of a managed object.
/**
     * Create a new managed pointer, pointing to a particular offset of a managed object.
     */
    static LLVMManagedPointer create(Object object, long offset) {
        assert object != null;
        return new LLVMPointerImpl(object, offset, null);
    }

    
Check whether an object is a LLVMManagedPointer. This method must be used instead of the regular Java instanceof operator. /**
     * Check whether an object is a {@link LLVMManagedPointer}. This method must be used instead of
     * the regular Java {@code instanceof} operator.
     */
    static boolean isInstance(Object object) {
        return object instanceof LLVMPointerImpl && ((LLVMPointerImpl) object).isManaged();
    }

    
Cast an object to a LLVMManagedPointer. This method must be used instead of the regular Java typecast operator. /**
     * Cast an object to a {@link LLVMManagedPointer}. This method must be used instead of the
     * regular Java typecast operator.
     */
    static LLVMManagedPointer cast(Object object) {
        assert isInstance(object);
        return (LLVMPointerImpl) object;
    }
}