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Re: i686 pic & DCmode


Having poked further, I find this in the testsuite:

pr11001-strlen-2.c
--begin
register int regvar asm("%eax");

char *
do_copy (char *str)
{
  return malloc (strlen (str) + 1);
}
--end

Is that even meaningful?  The doc's for a global reg var say:
'Choose a register that is normally saved and restored by function calls on your
machine, so that library routines will not clobber it.'

If one never made calls to a library unaware of the reg's global use, things would be ok. Except if one chose a register that is used by the ABI to return things, or by the pro/epilogue code as a scratch register.

Should attempts to use a call_used reg as a global reg var generate an error? Should it stop it being marked as a fixed_reg?

nathan


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