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Re: [m68k] Fix m68k-netbsdelf bootstrap


Andreas Schwab wrote:
Bernardo Innocenti <bernie@develer.com> writes:


Gunther Nikl wrote:

#if FRAME_POINTER_REGNUM == 14
/* Return a register name by index, handling fp nicely.  */
# define M68K_REGNAME(r) ( \
  ((r) == FRAME_POINTER_REGNUM && frame_pointer_needed) ? \
    M68K_FP_REG_NAME : reg_names[(r)])
#else
/* GAS and possibly other assemblers hard-code fp to a6.  */
# define M68K_REGNAME(r) reg_names[(r)]
#endif

This does only work if FRAME_POINTER_REGNUM is defined correctly before, eg. in config.gcc. However, since FRAME_POINTER_REGNUM is a compile-time constant you could move the check into the macro definition to get the same result :-)

No, it would work even if FRAME_POINTER_REGNUM is defined later, for the same reason Andreas' earlier patch works: the C preprocessor expands nested macros lazily, not at definition time.


Not in this case, since the #if expression is evaluated immediately, and
undefined macros are replaced with 0 here.

Doh!


Anyway, this conditional code is going to be ripped out
now that Gunther confirmed that GAS knows about %fp in
m68k-amigaos.

AFAIK, no other m68k targets have %fp != %a6.  Even so,
they'd better patch GAS too, otherwise they'd get broken
code for asm functions and inline macros.

--
 // Bernardo Innocenti - Develer S.r.l., R&D dept.
\X/  http://www.develer.com/



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