1 /*
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11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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13  * accompanied this code).
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23 package jdk.vm.ci.meta;
24 
25 /**
26  * Provides memory access operations for the target VM.
27  */
28 public interface MemoryAccessProvider {
29 
30     /**
31      * Reads a primitive value using a base address and a displacement.
32      *
33      * @param kind the {@link JavaKind} of the returned {@link JavaConstant} object
34      * @param base the base address from which the value is read
35      * @param displacement the displacement within the object in bytes
36      * @param bits the number of bits to read from memory
37      * @return the read value encapsulated in a {@link JavaConstant} object of {@link JavaKind} kind
38      * @throws IllegalArgumentException if the read is out of bounds of the object or {@code kind}
39      *             is {@link JavaKind#Void} or not {@linkplain JavaKind#isPrimitive() primitive}
40      *             kind or {@code bits} is not 8, 16, 32 or 64
41      */
readPrimitiveConstant(JavaKind kind, Constant base, long displacement, int bits)42     JavaConstant readPrimitiveConstant(JavaKind kind, Constant base, long displacement, int bits) throws IllegalArgumentException;
43 
44     /**
45      * Reads a Java {@link Object} value using a base address and a displacement.
46      *
47      * @param base the base address from which the value is read
48      * @param displacement the displacement within the object in bytes
49      * @return the read value encapsulated in a {@link Constant} object
50      * @throws IllegalArgumentException if the address computed from {@code base} and
51      *             {@code displacement} does not denote a location holding an {@code Object} value
52      */
readObjectConstant(Constant base, long displacement)53     JavaConstant readObjectConstant(Constant base, long displacement);
54 }
55