RTEMS CPU Architecture Supplement
XXX
As discussed above, the XXX and XXX instructions do
not automatically save any registers. Subroutines use the registers
D0, D1, A0, and A1 as scratch registers. These registers are
not preserved by subroutines therefore, the contents of
these registers should not be assumed upon return from any subroutine
call including but not limited to an RTEMS directive.
The GNU and Texas Instruments compilers follow the same conventions for register usage.
RTEMS CPU Architecture Supplement
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