This is a collection of Intel®’ IA32® Software Developer's Manuals (URL of the day) and AMD' AMD64 Architecture Programmer's Manual together with the related specifications, application notes, white papers, and change logs. The collection aims to keep all available revisions. It was originally created by Michal Necasek, see OS/2 Museum.

If you have a public document, related to the IA32® specifications and missing from the collection, please mail it to me. The content of this URL and all sub-ULRs is available for convenient bulk download by rsync x86docs password "" (empty).

WFIT -- A64

WFIT

Wait for interrupt with timeout

This instruction provides a hint 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.

System
(FEAT_WFxT)

313029282726252423222120191817161514131211109876543210
110101010000001100010000001Rd
CRmop2

Encoding

WFIT <Xt>

Decode for this encoding

if !IsFeatureImplemented(FEAT_WFxT) then EndOfDecode(Decode_UNDEF); end; let d : integer = UInt(Rd);

Assembler Symbols

<Xt>

Is the 64-bit name of the general-purpose source register, encoded in the "Rd" field.


2025-09_rel_asl1 2026-03-12 12:57:38

Copyright © 2010-2025 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.