STLR
Store-release register
This instruction 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.
This instruction is a data-independent-time instruction as described in About PSTATE.DIT.
It has encodings from 2 classes:
No offset
and
Pre-index
1
x
0
0
1
0
0
0
1
0
0
(1)
(1)
(1)
(1)
(1)
1
(1)
(1)
(1)
(1)
(1)
0
STLR <Wt>, [<Xn|SP>{, #0}]
1
STLR <Xt>, [<Xn|SP>{, #0}]
let t : integer{} = UInt(Rt);
let n : integer{} = UInt(Rn);
let wback : boolean = FALSE;
let offset : integer = 0;
let rt_unknown : boolean = FALSE;
let elsize : integer{} = 8 << UInt(size);
let datasize : integer{} = elsize;
let acquire : boolean = FALSE;
let tagchecked : boolean = n != 31;
1
x
0
1
1
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
1
0
0
STLR <Wt>, [<Xn|SP>, #-4]!
1
STLR <Xt>, [<Xn|SP>, #-8]!
if !IsFeatureImplemented(FEAT_LRCPC3) then EndOfDecode(Decode_UNDEF); end;
let wback : boolean = TRUE;
let t : integer{} = UInt(Rt);
let n : integer{} = UInt(Rn);
let datasize : integer{} = 8 << UInt(size);
let offset : integer = -1 * (1 << UInt(size));
let acquire : boolean = FALSE;
let tagchecked : boolean = TRUE;
var rt_unknown : boolean = FALSE;
if n == t && n != 31 then
let c : Constraint = 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 => EndOfDecode(Decode_UNDEF);
when Constraint_NOP => EndOfDecode(Decode_NOP);
end;
end;
<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.
var address : bits(64);
let dbytes : integer{} = datasize DIV 8;
let accdesc : AccessDescriptor = CreateAccDescAcqRel(MemOp_STORE, tagchecked, acquire, t);
if n == 31 then
CheckSPAlignment();
address = SP{64}();
else
address = X{64}(n);
end;
address = AddressAdd(address, offset, accdesc);
var data : bits(datasize);
if rt_unknown then
data = ARBITRARY : bits(datasize);
else
data = X{datasize}(t);
end;
Mem{datasize}(address, accdesc) = data;
if wback then
if n == 31 then
SP{64}() = address;
else
X{64}(n) = address;
end;
end;
2026-03-26 20:27:25
2026-03_rel