Unsigned maximum across vector
This instruction compares all the vector elements in the source SIMD&FP register, and writes the largest of the values as a scalar to the destination SIMD&FP register. All the values in this instruction are unsigned integer values.
Depending on the settings in the CPACR_EL1, CPTR_EL2, and CPTR_EL3 registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped.
| 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 | Q | 1 | 0 | 1 | 1 | 1 | 0 | size | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | Rn | Rd | |||||||||
| U | op | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_AdvSIMD) then EndOfDecode(Decode_UNDEF); if size:Q == '100' then EndOfDecode(Decode_UNDEF); if size == '11' then EndOfDecode(Decode_UNDEF); constant integer d = UInt(Rd); constant integer n = UInt(Rn); constant integer esize = 8 << UInt(size); constant integer datasize = 64 << UInt(Q); constant integer elements = datasize DIV esize; constant boolean unsigned = TRUE;
| <V> |
Is the destination width specifier,
encoded in
|
| <d> |
Is the number of the SIMD&FP destination register, encoded in the "Rd" field. |
| <Vn> |
Is the name of the SIMD&FP source register, encoded in the "Rn" field. |
| <T> |
Is an arrangement specifier,
encoded in
|
CheckFPAdvSIMDEnabled64(); constant bits(datasize) operand = V[n, datasize]; integer max = Int(Elem[operand, 0, esize], unsigned); for e = 1 to elements-1 constant integer element = Int(Elem[operand, e, esize], unsigned); max = Max(max, element); V[d, esize] = max<esize-1:0>;
If PSTATE.DIT is 1:
Internal version only: aarchmrs v2024-12_rel, pseudocode v2024-12_rel ; Build timestamp: 2024-12-15T22:18
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