Store Tag and Zero Multiple writes a naturally aligned block of N Allocation Tags and stores zero to the associated data locations, where the size of N is identified in DCZID_EL0.BS, and the Allocation Tag written to address A is taken from the source register bits<3:0>.
This instruction is undefined at EL0.
This instruction generates an Unchecked access.
If ID_AA64PFR1_EL1.MTE != 0b0010, this instruction is undefined.
| 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 |
| 1 | 1 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | Xn | Xt | ||||||||
if !HaveMTE2Ext() then UNDEFINED; integer t = UInt(Xt); integer n = UInt(Xn);
| <Xt> |
Is the 64-bit name of the general-purpose register to be transferred, encoded in the "Xt" field. |
| <Xn|SP> |
Is the 64-bit name of the general-purpose base register or stack pointer, encoded in the "Xn" field. |
if PSTATE.EL == EL0 then UNDEFINED; bits(64) data = X[t]; bits(4) tag = data<3:0>; bits(64) address; if n == 31 then CheckSPAlignment(); address = SP[]; else address = X[n]; integer size = 4*(2^(UInt(DCZID_EL0.BS))); address = Align(address,size); integer count = size >> LOG2_TAG_GRANULE; for i = 0 to count-1 AArch64.MemTag[address, AccType_NORMAL] = tag; Mem[address, TAG_GRANULE, AccType_NORMAL] = Zeros(8*TAG_GRANULE); address = address + TAG_GRANULE;
Internal version only: isa v32.15, AdvSIMD v29.05, pseudocode v2021-03, sve v2021-03_rc2 ; Build timestamp: 2021-03-30T21:36
Copyright © 2010-2021 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.