Qualified addressing

Qualified addressing lets you use the same symbol to refer to data in different storage locations. Qualified symbols are simply ordinary symbols prefixed by a symbol qualifier and a period. A symbol qualifier is used to specify which base register the assembler should use when converting an implicit address into its explicit base-displacement form. Before you use a symbol qualifier, you must have previously defined it in the name entry of a labeled USING instruction. For information about labeled USING instructions, see USING instruction. When defined, you can use a symbol qualifier to qualify any symbol that names a storage location within the range of the labeled USING. Qualified symbols may be used anywhere a relocatable term may be used.

The following examples show the use of qualified symbols. SOURCE and TARGET are both symbol qualifiers previously defined in two labeled USING instructions. X and Y are both symbols that name storage locations within the range of both labeled USING instructions.

         MVC             TARGET.X,SOURCE.X
         MVC             TARGET.Y+5(3),SOURCE.Y+5
         XC              TARGET.X+10(L'X-10),TARGET.X+10
         LA              2,SOURCE.Y

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