Store-Release Register stores a 32-bit word or a 64-bit doubleword to a memory location, from a register. The instruction also has memory ordering semantics as described in Load-Acquire, Store-Release. For information about addressing modes, see Load/Store addressing modes.
It has encodings from 2 classes: No offset and Pre-index
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 | x | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | (1) | (1) | (1) | (1) | (1) | 1 | (1) | (1) | (1) | (1) | (1) | Rn | Rt | ||||||||
size | L | Rs | o0 | Rt2 |
integer t = UInt(Rt); integer n = UInt(Rn); boolean wback = FALSE; integer offset = 0; boolean rt_unknown = FALSE; constant integer elsize = 8 << UInt(size); constant integer datasize = elsize; boolean tagchecked = n != 31;
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 | x | 0 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | Rn | Rt | ||||||||
size | L |
boolean wback = TRUE; integer t = UInt(Rt); integer n = UInt(Rn); constant integer datasize = 8 << UInt(size); integer offset = -1 * (1 << UInt(size)); boolean tagchecked = TRUE; boolean rt_unknown = FALSE; if n == t && n != 31 then Constraint c = ConstrainUnpredictable(Unpredictable_WBOVERLAPST); assert c IN {Constraint_NONE, Constraint_UNKNOWN, Constraint_UNDEF, Constraint_NOP}; case c of when Constraint_NONE rt_unknown = FALSE; // value stored is original value when Constraint_UNKNOWN rt_unknown = TRUE; // value stored is UNKNOWN when Constraint_UNDEF UNDEFINED; when Constraint_NOP EndOfInstruction();
<Wt> |
Is the 32-bit name of the general-purpose register to be transferred, encoded in the "Rt" field. |
<Xn|SP> |
Is the 64-bit name of the general-purpose base register or stack pointer, encoded in the "Rn" field. |
<Xt> |
Is the 64-bit name of the general-purpose register to be transferred, encoded in the "Rt" field. |
bits(64) address; constant integer dbytes = datasize DIV 8; AccessDescriptor accdesc = CreateAccDescAcqRel(MemOp_STORE, tagchecked); if n == 31 then CheckSPAlignment(); address = SP[]; else address = X[n, 64]; address = AddressAdd(address, offset, accdesc); bits(datasize) data; if rt_unknown then data = bits(datasize) UNKNOWN; else data = X[t, datasize]; Mem[address, dbytes, accdesc] = data; if wback then if n == 31 then SP[] = address; else X[n, 64] = address;
If PSTATE.DIT is 1, the timing of this instruction is insensitive to the value of the data being loaded or stored.
Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45
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