Read the first-fault register
Read the first-fault register (FFR) and place 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 | |||
S |
RDFFR <Pd>.B
if !IsFeatureImplemented(FEAT_SVE) then UNDEFINED; constant integer d = UInt(Pd);
CheckNonStreamingSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant bits(PL) ffr = FFR[PL]; P[d, PL] = ffr;
If FEAT_SVE2 is implemented or FEAT_SME is implemented, then if PSTATE.DIT is 1:
Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45
Copyright © 2010-2024 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.