9.22.4 Assembler Directives
The 68HC11 and 68HC12 version of
as have the following
specific assembler directives:
- The relax directive is used by the `GNU Compiler' to emit a specific
relocation to mark a group of instructions for linker relaxation.
The sequence of instructions within the group must be known to the linker
so that relaxation can be performed.
- This directive specifies the ABI. It overrides the `-mshort',
`-mlong', `-mshort-double' and `-mlong-double' options.
- This directive marks the symbol as a `far' symbol meaning that it
uses a `call/rtc' calling convention as opposed to `jsr/rts'.
During a final link, the linker will identify references to the `far'
symbol and will verify the proper calling convention.
- This directive marks the symbol as an interrupt entry point.
This information is then used by the debugger to correctly unwind the
frame across interrupts.
- This directive is defined for compatibility with the
`Specification for Motorola 8 and 16-Bit Assembly Language Input
Standard' and is ignored.