HLASM Language Reference

DC Instruction
| Symbols used in subfield 4 need not be previously defined, except in literals. For
| example:
| SYM DC FP(Rate5)'35.92'
| Rate5 EQU 5
| All expressions in program type must be evaluatable when the DC is processed.
| If program type is omitted, the assembler assigns a null to the program type, and
| querying the value using the SYSATTRP build-in function returns a null value.
Subfield 5: Modifier
The syntax for coding the modifier is shown in the subfield format on page 127.
You may omit the modifier subfield. Modifiers describe the length in bits or bytes
you want for a constant (in contrast to an implied length), and the scaling and
exponent for the constant.
The three modifiers are:
The length modifier (L), that explicitly defines the length in bytes you want for a
constant. For example:
LENGTH DC XL1'FF'
The scale modifier (S), that is only used with the fixed-point or floating-point
constants (for details, see “Scale Modifier” on page 138). For example:
SCALE DC FS8'35.92'
The exponent modifier (E), that is only used with fixed-point or floating-point
constants, and indicates the power of 10 by which the constant is to be
multiplied before conversion to its internal binary format. For example:
EXPON DC EE3'3.414'
If multiple modifiers are used, they must appear in this sequence: length, scale, and
exponent. For example:
ALL3 DC DL7S3E5'2.7182'
Symbols used in subfield 5 need not be previously defined, except in literals. For
example:
SYM DC FS(X)'35.92'
X EQU 7
Length Modifier
The length modifier indicates the number of bytes of storage into which the
constant is to be assembled. It is written as Ln, where n is either a decimal
self-defining term or an absolute expression enclosed by parentheses. It must
have a positive value.
When the length modifier is specified:
Its value determines the number of bytes of storage allocated to a constant. It
therefore determines whether the nominal value of a constant must be padded
or truncated to fit into the space allocated (see “Padding and Truncation of
Values” on page 130).
136 HLASM V1R5 Language Reference