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x86: cpu: Break out test for cpuid capabilities into separate function

This commit is contained in:
Diego Biurrun 2012-10-04 14:01:26 +02:00
parent cc5e9e5ff0
commit 54b243141e
1 changed files with 21 additions and 11 deletions
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32
libavutil/x86/cpu.c
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@ -86,6 +86,26 @@
#endif /* HAVE_INLINE_ASM */ #endif /* HAVE_INLINE_ASM */
#if ARCH_X86_64
#define cpuid_test() 1
#elif HAVE_INLINE_ASM || HAVE_RWEFLAGS
static int cpuid_test(void)
{
x86_reg a, c;
/* Check if CPUID is supported by attempting to toggle the ID bit in
* the EFLAGS register. */
get_eflags(a);
set_eflags(a ^ 0x200000);
get_eflags(c);
return a != c;
}
#endif
/* Function to test if multimedia instructions are supported... */ /* Function to test if multimedia instructions are supported... */
int ff_get_cpu_flags_x86(void) int ff_get_cpu_flags_x86(void)
{ {
@ -95,18 +115,8 @@ int ff_get_cpu_flags_x86(void)
int family = 0, model = 0; int family = 0, model = 0;
union { int i[3]; char c[12]; } vendor; union { int i[3]; char c[12]; } vendor;
#if ARCH_X86_32 if (!cpuid_test())
x86_reg a, c;
/* Check if CPUID is supported by attempting to toggle the ID bit in
* the EFLAGS register. */
get_eflags(a);
set_eflags(a ^ 0x200000);
get_eflags(c);
if (a == c)
return 0; /* CPUID not supported */ return 0; /* CPUID not supported */
#endif
cpuid(0, max_std_level, vendor.i[0], vendor.i[2], vendor.i[1]); cpuid(0, max_std_level, vendor.i[0], vendor.i[2], vendor.i[1]);