STGM

Store Tag Multiple writes a naturally aligned block of N Allocation Tags, where the size of N is identified in GMID_EL1.BS, and the Allocation Tag written to address A is taken from the source register at 4*A<7:4>+3:4*A<7:4>.

This instruction is UNDEFINED at EL0.

This instruction generates an Unchecked access.

Integer
(FEAT_MTE2)

313029282726252423222120191817161514131211109876543210
1101100110100000000000XnXt
opcimm9op2

STGM <Xt>, [<Xn|SP>]

if !IsFeatureImplemented(FEAT_MTE2) then UNDEFINED; integer t = UInt(Xt); integer n = UInt(Xn);

Assembler Symbols

<Xt>

Is the 64-bit name of the general-purpose source register, 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.

Operation

if PSTATE.EL == EL0 then UNDEFINED; bits(64) data = X[t, 64]; bits(64) address; if n == 31 then CheckSPAlignment(); address = SP[]; else address = X[n, 64]; integer size = 4 * (2 ^ (UInt(GMID_EL1.BS))); address = Align(address, size); constant integer count = size >> LOG2_TAG_GRANULE; integer index = UInt(address<LOG2_TAG_GRANULE+3:LOG2_TAG_GRANULE>); constant bits(64) curraddress = address; boolean devstoreunpred = FALSE; AccessDescriptor accdesc = CreateAccDescLDGSTG(MemOp_STORE, devstoreunpred); for i = 0 to count-1 bits(4) tag = Elem[data, index, 4]; AArch64.MemTag[address, accdesc] = tag; address = GenerateAddress(address, TAG_GRANULE, accdesc); index = index + 1;


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

Copyright © 2010-2023 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.