Function core_arch::x86::_xsaveopt

pub unsafe fn _xsaveopt(mem_addr: *mut u8, save_mask: u64)

This is supported on x86 and target feature xsave,xsaveopt only.

Performs a full or partial save of the enabled processor states to memory at mem_addr.

State is saved based on bits [62:0] in save_mask and XCR0. mem_addr must be aligned on a 64-byte boundary. The hardware may optimize the manner in which data is saved. The performance of this instruction will be equal to or better than using the XSAVE instruction.

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