HLASM Language Reference

DC Instruction—Binary Floating-Point Special Values
nominal_value
defines the special value to be generated.
Notes:
1. The nominal value can be in mixed case.
2. SNAN assembles with an exponent of ones and 01 in the high order fraction
bits with the remainder of the fraction containing zeros.
3. QNAN assembles with an exponent of ones and 11 in the high order fraction
bits with the remainder of the fraction containing zeros.
4. NAN assembles with an exponent of one and 10 in the high order fraction bits
with the remainder of the fraction containing zeros.
5. MIN assembles as a normalized minimum value, that is an exponent of one
| and a fraction of zeros for binary constants, and a fraction with a leading
| hexadecimal digit 1 followed by zeros for hexadecimal constants.
| 6. DMIN assembles as a denormalized minimum value with an exponent of zeros
| and a fraction of all zeros except for a low order bit of one.
7. INF assembles with an exponent of ones and a fraction of zeros.
| 8. MAX assembles with a fraction of all ones and an exponent of all ones for
| hexadecimal constants, and an exponent of all ones except for the low bit for
| binary constants.
Literal Constants
Literal constants let you define and refer to data directly in machine instruction
operands. You do not need to define a constant separately in another part of your
source module. The differences between a literal, a data constant, and a
self-defining term are described in “Literals” on page 40.
A literal constant is specified in the same way as the operand of a DC instruction.
The general rules for the operand subfields of a DC instruction also apply to the
subfield of a literal constant. Moreover, the rules that apply to the individual types
of constants apply to literal constants as well.
However, literal constants differ from DC operands in the following ways:
Literals must be preceded by an equal sign.
Multiple operands are not allowed.
The duplication factor must not be zero.
Symbols used in the duplication factor or length modifier must be previously
defined. Scale and Exponent modifiers do not need pre-definition.
If an address-type literal constant specifies a duplication factor greater than one
and a nominal value containing the location counter reference, the value of the
location counter reference is not incremented, but remains the same for each
duplication.
The assembler groups literals together by size. If you use a literal constant,
the alignment of the constant can be different than might be the case for an
explicit constant. See “Literal Pool” on page 44.
Chapter 5. Assembler Instruction Statements 171