as for the Alpha supports many additional directives for compatibility with the native assembler. This section describes them only briefly.
These are the additional directives in
as for the Alpha:
.mdebuginformation, this will create a procedure descriptor for the function. In ELF, it will mark the symbol as a function a-la the generic
$26) is saved first.
This and the other directives that describe the stack frame are
currently only used when generating
.mdebug information. They
may in the future be used to generate DWARF2
information for hand written assembly.
$sp. The frame pointer is frameoffset bytes below the CFA. The return address is initially located in retreg until it is saved as indicated in
.mask. For compatibility with OSF/1 an optional argoffset parameter is accepted and ignored. It is believed to indicate the offset from the CFA to the saved argument registers.
$27. 0 indicates that
$27is not used; 1 indicates that the first two instructions of the function use
$27to perform a load of the GP register; 2 indicates that
$27is used in some non-standard way and so the linker cannot elide the load of the procedure vector during relaxation.
$27register, similar to
.prologue, but without the other semantics of needing to be inside an open
The which argument should be either
no, indicating that
$27 is not used, or
std, indicating that the first two
instructions of the function perform a GP load.
One might use this directive instead of
.prologue if you are
also using dwarf2 CFI directives.
$28) register. Some macros may not be expanded without this and will generate an error message if
noatis in effect. When
atis in effect, a warning will be generated if
$atis used by the programmer.
br $31,labelare considered alternate forms and not macros.
The following directives are recognized for compatibility with the OSF/1 assembler but are ignored.
.proc .aproc .reguse .livereg .option .aent .ugen .eflag .alias .noalias