Function core::arch::x86_64::_xsetbv

pub unsafe fn _xsetbv(a: u32, val: u64)

Available on (x86 or x86-64) and target feature xsave and x86-64 only.

Copies 64-bits from val to the extended control register (XCR) specified by a.

Currently only XFEATURE_ENABLED_MASK XCR is supported.

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