core::arch::x86

Function __cpuid_count

1.27.0 · source
pub unsafe fn __cpuid_count(leaf: u32, sub_leaf: u32) -> CpuidResult
Available on x86 and (x86 or x86-64) only.
Expand description

Returns the result of the cpuid instruction for a given leaf (EAX) and sub_leaf (ECX).

The highest-supported leaf value is returned by the first tuple argument of __get_cpuid_max(0). For leaves containung sub-leaves, the second tuple argument returns the highest-supported sub-leaf value.

The CPUID Wikipedia page contains how to query which information using the EAX and ECX registers, and the interpretation of the results returned in EAX, EBX, ECX, and EDX.

The references are: