HLASM Language Reference

Terms, Literals, and Expressions
It can also be specified in literal constants. See “Literals” on page 40. For
example:
| THERE L =3A()
| generates three identical address constants, each with value A(THERE).
| The value of the location counter reference (*) is the same as the value of the
| symbol THERE, the current value of the location counter of the control section
in which the asterisk (*) is specified as a term. The asterisk has the same
value as the address of the first byte of the instruction in which it appears. For
example:
HERE B +8
where the value of is the value of HERE.
For the value of the asterisk in address constants with duplication factors, see
“Subfield 1: Duplication Factor” on page 132 of “DC Instruction” on page 126, and
| “Address Constants—A and Y” on page 153. For a discussion of location counter
| references in literals, see “Subfield 1: Duplication Factor” on page 132.
Symbol Length Attribute Reference
The length attribute of a symbol may be used as a term. Reference to the attribute
is made by coding L' followed by the symbol, as in:
L'BETA
The length attribute of BETA is substituted for the term. When you specify a symbol
length attribute reference, you obtain the length of the instruction or data named by
a symbol. You can use this reference as a term in instruction operands to:
Specify assembler-determined storage area lengths
Cause the assembler to compute length specifications for you
Build expressions to be evaluated by the assembler
The symbol length attribute reference must be specified according to the following
rules:
| The format must be L' immediately followed by a valid symbol (L'SYMBOL), an
| expression (L'SYMBOL+SYMBOL2-SYMBOL7), or the location counter reference (L').
| If the operand is an expression, the length attribute of its leftmost term is used.
| Symbols must be defined in the same source module in which the symbol
length attribute reference is specified.
The symbol length attribute reference can be used in the operand of any
instruction that requires an absolute term. However, it cannot be used in the
form L' in any instruction or expression that requires a previously defined
symbol.
The value of the length attribute is normally the length in bytes of the storage area
required by an instruction, constant, or field represented by a symbol. The
assembler stores the value of the length attribute in the symbol table along with the
address value assigned to the symbol.
When the assembler encounters a symbol length attribute reference, it substitutes
the value of the attribute from the symbol table entry for the symbol specified.
38 HLASM V1R5 Language Reference