Function _xrstors
#[target_feature(enable = "xsave", enable = "xsaves")]
pub unsafe fn _xrstors(mem_addr: *const u8, rs_mask: u64)Performs a full or partial restore of the enabled processor states using the
state information stored in memory at mem_addr.
xrstors differs from xrstor in that it can restore state components
corresponding to bits set in the IA32_XSS MSR; xrstors cannot restore
from an xsave area in which the extended region is in the standard form.
State is restored based on bits [62:0] in rs_mask, XCR0, and
mem_addr.HEADER.XSTATE_BV. mem_addr must be aligned on a 64-byte
boundary.