Load single 4-element structure to one lane of four registers loads one 4-element structure from memory into corresponding elements of four registers. Elements of the registers that are not loaded are unchanged. For details of the addressing mode, see Advanced SIMD addressing mode.
Depending on settings in the CPACR, NSACR, and HCPTR registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be undefined, or trapped to Hyp mode. For more information, see Enabling Advanced SIMD and floating-point support.
It has encodings from the following instruction sets: A32 ( A1 , A2 and A3 ) and T32 ( T1 , T2 and T3 ) .
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 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | D | 1 | 0 | Rn | Vd | 0 | 0 | 1 | 1 | index_align | Rm | ||||||||||||
size |
if size == '11' then SEE "VLD4 (single 4-element structure to all lanes)"; ebytes = 1; index = UInt(index_align<3:1>); inc = 1; alignment = if index_align<0> == '0' then 1 else 4; d = UInt(D:Vd); d2 = d + inc; d3 = d2 + inc; d4 = d3 + inc; n = UInt(Rn); m = UInt(Rm); wback = (m != 15); register_index = (m != 15 && m != 13); if n == 15 || d4 > 31 then UNPREDICTABLE;
If d4 > 31, then one of the following behaviors must occur:
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 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | D | 1 | 0 | Rn | Vd | 0 | 1 | 1 | 1 | index_align | Rm | ||||||||||||
size |
if size == '11' then SEE "VLD4 (single 4-element structure to all lanes)"; ebytes = 2; index = UInt(index_align<3:2>); inc = if index_align<1> == '0' then 1 else 2; alignment = if index_align<0> == '0' then 1 else 8; d = UInt(D:Vd); d2 = d + inc; d3 = d2 + inc; d4 = d3 + inc; n = UInt(Rn); m = UInt(Rm); wback = (m != 15); register_index = (m != 15 && m != 13); if n == 15 || d4 > 31 then UNPREDICTABLE;
If d4 > 31, then one of the following behaviors must occur:
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 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | D | 1 | 0 | Rn | Vd | 1 | 0 | 1 | 1 | index_align | Rm | ||||||||||||
size |
if size == '11' then SEE "VLD4 (single 4-element structure to all lanes)"; if index_align<1:0> == '11' then UNDEFINED; ebytes = 4; index = UInt(index_align<3>); inc = if index_align<2> == '0' then 1 else 2; alignment = if index_align<1:0> == '00' then 1 else 4 << UInt(index_align<1:0>); d = UInt(D:Vd); d2 = d + inc; d3 = d2 + inc; d4 = d3 + inc; n = UInt(Rn); m = UInt(Rm); wback = (m != 15); register_index = (m != 15 && m != 13); if n == 15 || d4 > 31 then UNPREDICTABLE;
If d4 > 31, then one of the following behaviors must occur:
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | D | 1 | 0 | Rn | Vd | 0 | 0 | 1 | 1 | index_align | Rm | ||||||||||||
size |
if size == '11' then SEE "VLD4 (single 4-element structure to all lanes)"; ebytes = 1; index = UInt(index_align<3:1>); inc = 1; alignment = if index_align<0> == '0' then 1 else 4; d = UInt(D:Vd); d2 = d + inc; d3 = d2 + inc; d4 = d3 + inc; n = UInt(Rn); m = UInt(Rm); wback = (m != 15); register_index = (m != 15 && m != 13); if n == 15 || d4 > 31 then UNPREDICTABLE;
If d4 > 31, then one of the following behaviors must occur:
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | D | 1 | 0 | Rn | Vd | 0 | 1 | 1 | 1 | index_align | Rm | ||||||||||||
size |
if size == '11' then SEE "VLD4 (single 4-element structure to all lanes)"; ebytes = 2; index = UInt(index_align<3:2>); inc = if index_align<1> == '0' then 1 else 2; alignment = if index_align<0> == '0' then 1 else 8; d = UInt(D:Vd); d2 = d + inc; d3 = d2 + inc; d4 = d3 + inc; n = UInt(Rn); m = UInt(Rm); wback = (m != 15); register_index = (m != 15 && m != 13); if n == 15 || d4 > 31 then UNPREDICTABLE;
If d4 > 31, then one of the following behaviors must occur:
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | D | 1 | 0 | Rn | Vd | 1 | 0 | 1 | 1 | index_align | Rm | ||||||||||||
size |
if size == '11' then SEE "VLD4 (single 4-element structure to all lanes)"; if index_align<1:0> == '11' then UNDEFINED; ebytes = 4; index = UInt(index_align<3>); inc = if index_align<2> == '0' then 1 else 2; alignment = if index_align<1:0> == '00' then 1 else 4 << UInt(index_align<1:0>); d = UInt(D:Vd); d2 = d + inc; d3 = d2 + inc; d4 = d3 + inc; n = UInt(Rn); m = UInt(Rm); wback = (m != 15); register_index = (m != 15 && m != 13); if n == 15 || d4 > 31 then UNPREDICTABLE;
If d4 > 31, then one of the following behaviors must occur:
For more information about the constrained unpredictable behavior of this instruction, see Architectural Constraints on UNPREDICTABLE behaviors, and particularly VLD4 (single 4-element structure to one lane).
<c> |
For encoding A1, A2 and A3: see Standard assembler syntax fields. This encoding must be unconditional. |
For encoding T1, T2 and T3: see Standard assembler syntax fields. |
<q> |
<size> |
Is the data size,
encoded in
|
<Rn> |
Is the general-purpose base register, encoded in the "Rn" field. |
<align> |
Is the optional alignment. Whenever <align> is omitted, the standard alignment is used, see Unaligned data access, and the encoding depends on <size>:
Whenever <align> is present, the permitted values and encoding depend on <size>:
: is the preferred separator before the <align> value, but the alignment can be specified as @<align>, see Advanced SIMD addressing mode. |
<Rm> |
Is the general-purpose index register containing an offset applied after the access, encoded in the "Rm" field. |
For more information about the variants of this instruction, see Advanced SIMD addressing mode.
if ConditionPassed() then EncodingSpecificOperations(); CheckAdvSIMDEnabled(); address = R[n]; boolean nontemporal = FALSE; boolean tagchecked = FALSE; AccessDescriptor accdesc = CreateAccDescASIMD(MemOp_LOAD, nontemporal, tagchecked); if !IsAligned(address, alignment) then AArch32.Abort(address, AlignmentFault(accdesc)); Elem[D[d], index,8*ebytes] = MemU[address,ebytes]; Elem[D[d2],index,8*ebytes] = MemU[address+ebytes,ebytes]; Elem[D[d3],index,8*ebytes] = MemU[address+2*ebytes,ebytes]; Elem[D[d4],index,8*ebytes] = MemU[address+3*ebytes,ebytes]; if wback then if register_index then R[n] = R[n] + R[m]; else R[n] = R[n] + 4*ebytes;
If CPSR.DIT is 1, the timing of this instruction is insensitive to the value of the data being loaded or stored.
Internal version only: isa v01_31, pseudocode v2023-06_rel, sve v2023-06_rel ; Build timestamp: 2023-07-04T18:06
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