Signed Absolute Difference Long. This instruction subtracts the vector elements of the second source SIMD&FP register from the corresponding vector elements of the first source SIMD&FP register, places the absolute value of the results into a vector, and writes the vector to the lower or upper half of the destination SIMD&FP register. The destination vector elements are twice as long as the source vector elements.
The SABDL instruction extracts each source vector from the lower half of each source register, while the SABDL2 instruction extracts each source vector from the upper half of each 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.
| 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 | 0 | 0 | 1 | 1 | 1 | 0 | size | 1 | Rm | 0 | 1 | 1 | 1 | 0 | 0 | Rn | Rd | |||||||||||||
| U | op | ||||||||||||||||||||||||||||||
integer d = UInt(Rd); integer n = UInt(Rn); integer m = UInt(Rm); if size == '11' then UNDEFINED; integer esize = 8 << UInt(size); integer datasize = 64; integer part = UInt(Q); integer elements = datasize DIV esize; boolean accumulate = (op == '0'); boolean unsigned = (U == '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 first SIMD&FP source register, encoded in the "Rn" field. |
| <Tb> |
Is an arrangement specifier,
encoded in
|
| <Vm> |
Is the name of the second SIMD&FP source register, encoded in the "Rm" field. |
CheckFPAdvSIMDEnabled64(); bits(datasize) operand1 = Vpart[n, part]; bits(datasize) operand2 = Vpart[m, part]; bits(2*datasize) result; integer element1; integer element2; bits(2*esize) absdiff; result = if accumulate then V[d] else Zeros(); for e = 0 to elements-1 element1 = Int(Elem[operand1, e, esize], unsigned); element2 = Int(Elem[operand2, e, esize], unsigned); absdiff = Abs(element1 - element2)<2*esize-1:0>; Elem[result, e, 2*esize] = Elem[result, e, 2*esize] + absdiff; V[d] = result;
If 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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