Store Allocation Tag and Pair of registers stores an Allocation Tag and two 64-bit doublewords to memory, from two registers. The address used for the store is calculated from the base register and an immediate signed offset scaled by the Tag granule. The Allocation Tag is calculated from the Logical Address Tag in the base register.
This instruction generates an Unchecked access.
It has encodings from 3 classes: Post-index , Pre-index and Signed offset
| 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 | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | simm7 | Xt2 | Xn | Xt | ||||||||||||||||||
if !HaveMTEExt() then UNDEFINED; integer n = UInt(Xn); integer t = UInt(Xt); integer t2 = UInt(Xt2); bits(64) offset = LSL(SignExtend(simm7, 64), LOG2_TAG_GRANULE); boolean writeback = TRUE; boolean postindex = TRUE;
| 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 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | simm7 | Xt2 | Xn | Xt | ||||||||||||||||||
if !HaveMTEExt() then UNDEFINED; integer n = UInt(Xn); integer t = UInt(Xt); integer t2 = UInt(Xt2); bits(64) offset = LSL(SignExtend(simm7, 64), LOG2_TAG_GRANULE); boolean writeback = TRUE; boolean postindex = FALSE;
| 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 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | simm7 | Xt2 | Xn | Xt | ||||||||||||||||||
if !HaveMTEExt() then UNDEFINED; integer n = UInt(Xn); integer t = UInt(Xt); integer t2 = UInt(Xt2); bits(64) offset = LSL(SignExtend(simm7, 64), LOG2_TAG_GRANULE); boolean writeback = FALSE; boolean postindex = FALSE;
| <Xt1> |
Is the 64-bit name of the first general-purpose register to be transferred, encoded in the "Xt" field. |
| <Xt2> |
Is the 64-bit name of the second general-purpose register to be transferred, encoded in the "Xt2" field. |
| <Xn|SP> |
Is the 64-bit name of the general-purpose base register or stack pointer, encoded in the "Xn" field. |
bits(64) address; bits(64) data1; bits(64) data2; SetTagCheckedInstruction(FALSE); if n == 31 then CheckSPAlignment(); address = SP[]; else address = X[n]; data1 = X[t]; data2 = X[t2]; if !postindex then address = address + offset; if address != Align(address, TAG_GRANULE) then iswrite = TRUE; secondstage = FALSE; AArch64.Abort(address, AlignmentFault(AccType_NORMAL, iswrite, secondstage)); Mem[address, 8, AccType_NORMAL] = data1; Mem[address+8, 8, AccType_NORMAL] = data2; AArch64.MemTag[address, AccType_NORMAL] = AArch64.AllocationTagFromAddress(address); if writeback then if postindex then address = address + offset; if n == 31 then SP[] = address; else X[n] = address;
Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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