SPARC, register renaming, __builtin_return_address

[Mark Mitchell]

>>>>> "David" == David Edelsohn <dje@watson.ibm.com> writes:

    David> 	I think this is the key point: either return 0 for
    David> b_r_a(1) or force a stack-frame when b_r_a() is detected.

We can't control the caller.  To do b_r_a (N) we have to make
assumptions about the the call frames up the stack.  I think we can
assume whatever the psABI requires on the platform, which is usually
enough to do the unwinding. 

But, I'm not sure what "force a stack frame" means.

--
Mark Mitchell                   mark@codesourcery.com
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