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package org.graalvm.compiler.nodes.memory;

A special form of MemoryAccess requiring barrier information for garbage collection. /**
 *
 * A special form of {@linkplain MemoryAccess} requiring barrier information for garbage collection.
 */
public interface OnHeapMemoryAccess extends MemoryAccess {

    
The types of (write/read) barriers attached to stores.
/**
     * The types of (write/read) barriers attached to stores.
     */
    enum BarrierType {
        
Primitive access which do not necessitate barriers.
/**
         * Primitive access which do not necessitate barriers.
         */
        NONE,
        
Array object access.
/**
         * Array object access.
         */
        ARRAY,
        
Field object access.
/**
         * Field object access.
         */
        FIELD,
        
Unknown (aka field or array) object access.
/**
         * Unknown (aka field or array) object access.
         */
        UNKNOWN,
        
Weak field access (e.g. Hotspot's Reference.referent field).
/**
         * Weak field access (e.g. Hotspot's Reference.referent field).
         */
        WEAK_FIELD,
        
An access which requires a dynamic check for Weak field access (e.g. Hotspot's
Reference.referent field).
/**
         * An access which requires a dynamic check for Weak field access (e.g. Hotspot's
         * Reference.referent field).
         */
        MAYBE_WEAK_FIELD
    }

    
Gets the write barrier type for that particular access.
/**
     * Gets the write barrier type for that particular access.
     */
    BarrierType getBarrierType();

}