Wait For Interrupt with Timeout is a hint instruction that indicates that the PE can enter a low-power state and remain there until either a local timeout event or a wakeup event occurs. For more information, see Wait For Interrupt.
As described in Wait For Interrupt, the execution of a WFIT instruction that would otherwise cause entry to a low-power state can be trapped to a higher Exception level. See:
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WFIT <Xt>
if !HaveFeatWFxT() then UNDEFINED; integer d = UInt(Rd);
bits(64) operand = X[d]; integer localtimeout = UInt(operand); if Halted() && ConstrainUnpredictableBool(Unpredictable_WFxTDEBUG) then EndOfInstruction(); Hint_WFI(localtimeout, WFxType_WFIT);
Internal version only: isa v32.13, AdvSIMD v29.05, pseudocode v2020-12, sve v2020-12 ; Build timestamp: 2020-12-16T16:53
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