Copy signed integer immediate to vector elements (zeroing)
Copy a signed integer immediate to each active element in the destination vector. Inactive elements in the destination vector register are set to zero.
The immediate operand is a signed value in the range -128 to +127, and for element widths of 16 bits or higher it may also be a signed multiple of 256 in the range -32768 to +32512 (excluding 0).
The immediate is encoded in 8 bits with an optional left shift by 8. The preferred disassembly when the shift option is specified is "#<simm8>, LSL #8". However an assembler and disassembler may also allow use of the shifted 16-bit value unless the immediate is 0 and the shift amount is 8, which must be unambiguously described as "#0, LSL #8".
This instruction is used by the alias MOV (immediate, predicated, zeroing).
| 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 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | size | 0 | 1 | Pg | 0 | 0 | sh | imm8 | Zd | |||||||||||||||
| M | |||||||||||||||||||||||||||||||
if !HaveSVE() && !HaveSME() then UNDEFINED; if size:sh == '001' then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer d = UInt(Zd); boolean merging = FALSE; integer imm = SInt(imm8); if sh == '1' then imm = imm << 8;
| <Zd> |
Is the name of the destination scalable vector register, encoded in the "Zd" field. |
| <T> |
Is the size specifier,
encoded in
|
| <Pg> |
Is the name of the governing scalable predicate register, encoded in the "Pg" field. |
| <imm> |
Is a signed immediate in the range -128 to 127, encoded in the "imm8" field. |
| <shift> |
Is the optional left shift to apply to the immediate, defaulting to LSL #0 and
encoded in
|
CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(VL) dest = Z[d]; bits(VL) result; for e = 0 to elements-1 if ElemP[mask, e, esize] == '1' then Elem[result, e, esize] = imm<esize-1:0>; elsif merging then Elem[result, e, esize] = Elem[dest, e, esize]; else Elem[result, e, esize] = Zeros(); Z[d] = result;
If FEAT_SVE2 is enabled or FEAT_SME is enabled, then when PSTATE.DIT is 1:
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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