m68k/cc issue (was Re: gettimeofday seconds rollover problem?)
Till Straumann
strauman at slac.stanford.edu
Mon Feb 27 21:03:02 UTC 2006
Someone (don't have enough m68k knowledge in my cache
behind my eyes) should be answer this. It's not
rocket science:
Do the enable/disable inlines potentially modify
a bit in the 'cc' that the ABI declares non-volatile?
BTW: I couldn't help playing with this and it seems
that 'cc' is ignored anyways on m68k and on powerpc
(I know that on the powerpc you must explicitely
list the non-volatile crX in the clobber list if you
modify them from an asm, 'cc' is definitely ignored)
void blah()
{
asm volatile("":::"cc");
}
is compiled (m68k-rtems-gcc -m528x, version 4.0.2) into
Disassembly of section .text:
00000000 <blah>:
0: 4e75 rts
FWIW
-- T.
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