The 68HC11 and 68HC12 version of as have the following
specific assembler directives:
.relax
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.
.mode [mshort|mlong|mshort-double|mlong-double]
This directive specifies the ABI. It overrides the -mshort,
-mlong, -mshort-double and -mlong-double options.
.far
symbol
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.
.interrupt
symbol
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.
.xrefb
symbol
This directive is defined for compatibility with the Specification for Motorola 8 and 16-Bit Assembly Language Input Standard and is ignored.
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