Unsigned extend Long. This instruction copies each vector element from the lower or upper half of the source SIMD&FP register into a vector, and writes the vector to the destination SIMD&FP register. The destination vector elements are twice as long as the source vector elements.
The UXTL instruction extracts vector elements from the lower half of the source register. The UXTL2 instruction extracts vector elements from the upper half of the source register.
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.
This is an alias of USHLL, USHLL2. This means:
| 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 | 1 | 0 | != 0000 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | Rn | Rd | |||||||||||
| U | immh | immb | opcode | ||||||||||||||||||||||||||||
is equivalent to
USHLL{2} <Vd>.<Ta>, <Vn>.<Tb>, #0
and is the preferred disassembly when BitCount(immh) == 1.
| <Vd> |
Is the name of the SIMD&FP destination register, encoded in the "Rd" field. |
| <Ta> |
Is an arrangement specifier,
encoded in
|
| <Vn> |
Is the name of the SIMD&FP source register, encoded in the "Rn" field. |
| <Tb> |
Is an arrangement specifier,
encoded in
|
The description of USHLL, USHLL2 gives the operational pseudocode for this instruction.
If PSTATE.DIT is 1:
Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46
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