Texas Instruments TMS320C54x, Руководство пользователя

Страница: 106 / 469

Miscellaneous Directives
4-23 Assembler Directives
4.10 Miscellaneous Directives
These directives enable miscellaneous functions or features:
-
The .algebraic directive tells the assembler that the file contains algebraic
assembly source code. This must be the first line in the file if the –mg as-
sembler option is not used.
-
The .c_mode directive tells the assembler that calls and branches are
within the normal 16-bit address range. This is the default behavior of the
assembler.
-
The .end directive terminates assembly. It should be the last source
statement of a program. This directive has the same effect as an
end-of-file.
-
The .far_mode directive tells the assembler that calls are far calls.
-
The .mmregs directive defines symbolic names for the memory-mapped
register. Using .mmregs is the same as executing a .set for all
memory-mapped registers. See Table 4–2 on page 4-70 for a list of
memory-mapped registers.
-
The .newblock directive resets local labels. Local labels are symbols of
the form $n or name?. They are defined when they appear in the label field.
Local labels are temporary labels that can be used as operands for jump
instructions. The .newblock directive limits the scope of local labels by re-
setting them after they are used. For more information about local labels,
see subsection 3.8.6,
Local Labels, on page 3-21.
-
The .sblock directive designates sections for blocking. Blocking is an
address alignment mechanism similar to page alignment, but weaker. A
blocked section is guaranteed not to cross a page boundary (128 words)
if it is smaller than a page, or to start on a page boundary if it is larger than
a page. Note that this directive allows specification of blocking for initial-
ized sections only, not uninitialized sections declared with .usect or the
.bss section. The section names may or may not be enclosed in quotes.
-
The .version directive determines the processor for which instructions are
being built. Each ’C54x device has its own value.