Read the first-fault register
This instruction reads the first-fault register (FFR) and places the read values in the destination predicate without predication.
This instruction is illegal when executed in Streaming SVE mode, unless FEAT_SME_FA64 is implemented and enabled.
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 0 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | Pd | |||
| op | S | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE) then EndOfDecode(Decode_UNDEF); end; let d : integer = UInt(Pd);
CheckNonStreamingSVEEnabled(); let VL : integer{} = CurrentVL(); let PL : integer{} = VL DIV 8; let ffr : bits(PL) = FFR{}(); P{PL}(d) = ffr;
2026-03_rel 2026-03-26 20:48:11
Copyright © 2010-2026 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.