HLASM Language Reference

Addressing
Literal Pools
ALPHA LR 3,4
CR 4,6
BCR 1,14
BETA AR 2,3
Literals, collected into pools by the assembler, are assembled as part of the
executable control section to which the pools belong. If a LTORG instruction is
specified at the end of each control section or element, the literals specified for that
section or element are assembled into the pool starting at the LTORG instruction.
If no LTORG instruction is specified, a literal pool containing all the literals used in
| the whole source module is assembled at the end of the first control section or at
| the end of the B_TEXT class belonging to the first section. This literal pool appears
in the listings after the END instruction. For more information about the LTORG
instruction, see “LTORG Instruction” on page 193.
Independently Addressed Segments: If any control section is divided into
independently addressed segments, a LTORG instruction should be specified at the
end of each segment to create a separate literal pool for that segment.
Establishing Residence and Addressing Mode
The AMODE and RMODE instructions specify the addressing mode (AMODE) and
the residence mode (RMODE) to be associated with control sections in the object
deck. These modes may be specified for the following types of control sections:
Control section (for example START, CSECT)
Unnamed control section
Common control section (COM instruction)
The assembler sets the AMODE and RMODE indicators in the ESD record for each
applicable control section in an assembly. The linker stores the AMODE and
RMODE values in the load module. They are subsequently used by the loader
program that brings the load module into storage. The loader program uses the
RMODE value to determine where it loads the load module, and passes the
AMODE value to the operating system to establish the addressing mode.
| When you specify the GOFF option, the RMODE value specified for a
| section is by default assigned to the B_TEXT class, and the AMODE specified for the
| section is assigned to an entry point having the section name and the location of
| the first byte of class B_TEXT. If the source program defines additional classes,
| each class may be assigned its own RMODE, and an entry point in any class may
| be assigned its own AMODE.
For more information about the AMODE and RMODE instructions, see “AMODE
Instruction” on page 110 and “RMODE Instruction” on page 211.
Symbolic Linkages
Symbols can be defined in one module and referred to in another, which results in
symbolic linkages between independently assembled program sections. These
linkages can be made only if the assembler can provide information about the
linkage symbols to the linker, which resolves the linkage references at link-edit
time.
68 HLASM V1R5 Language Reference