Krzysztof Helt 94f6bac105 x86: do not allow to optimize flag_is_changeable_p() (rev. 2)
The flag_is_changeable_p() is used by
has_cpuid_p() which can return different results
in the code sequence below:

 if (!have_cpuid_p())
      identify_cpu_without_cpuid(c);

  /* cyrix could have cpuid enabled via c_identify()*/
  if (!have_cpuid_p())
      return;

Otherwise, the gcc 3.4.6 optimizes these two calls
into one which make the code not working correctly.

Cyrix cpus have the CPUID instruction enabled before
the second call to the have_cpuid_p() but
it is not detected due to the gcc optimization.
Thus the ARR registers (mtrr like) are not detected
on such a cpu.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13 10:33:13 +02:00
..
2008-09-08 15:32:02 +02:00
2008-06-03 14:43:00 -07:00
2008-07-31 23:56:27 +02:00
2008-09-10 08:21:05 +02:00
2008-09-04 21:09:45 +02:00