Signed Multiply-Subtract Long (vector). This instruction multiplies corresponding signed integer values in the lower or upper half of the vectors of the two source SIMD&FP registers, and subtracts the results from the vector elements of the destination SIMD&FP register. The destination vector elements are twice as long as the elements that are multiplied.
The SMLSL instruction extracts each source vector from the lower half of each source register, while the SMLSL2 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 | 1 | 0 | 1 | 0 | 0 | 0 | Rn | Rd | |||||||||||||
| U | o1 | ||||||||||||||||||||||||||||||
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 sub_op = (o1 == '1'); 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
size:
|
| <Vn> |
Is the name of the first SIMD&FP source register, encoded in the "Rn" field. |
| <Tb> |
Is an arrangement specifier,
encoded in
size:Q:
|
| <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) operand3 = V[d]; bits(2*datasize) result; integer element1; integer element2; bits(2*esize) product; bits(2*esize) accum; for e = 0 to elements-1 element1 = Int(Elem[operand1, e, esize], unsigned); element2 = Int(Elem[operand2, e, esize], unsigned); product = (element1 * element2)<2*esize-1:0>; if sub_op then accum = Elem[operand3, e, 2*esize] - product; else accum = Elem[operand3, e, 2*esize] + product; Elem[result, e, 2*esize] = accum; V[d] = result;
Internal version only: isa v32.13, AdvSIMD v29.04, pseudocode morello-2022-01_rc2, capabilities morello-2022-01_rc2 ; Build timestamp: 2022-01-11T11:23
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