Re: Gnu C compiler RTL question

dadorran@my-dejanews.com wrote:
: I read somewhere that the RTL is independent of the machine description, but
: looking at some compiled code shows that it does depend on the registers used
: as the stack and frame pointers.


: Are thes the only instances where this occurs??


GCC RTL is machine independent in general, but the specific RTL generated
is machine-dependent. Some machine-dependent RTL features:


    - machine specific register usage:
            frame pointer, stack pointer, function return value register,
            function return pointer register


    - existence of a conditional code register, represented by cc0_rtx


    - the forms of the RTL insns generated depend on the availability of
        machine instructions; for example, this type if RTL is not generated
        for a machine with a load/store architecture:


                (set (reg ...)
                          (plus (reg ...) (mem ...)))


Tim
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