Unsigned Multiply-Subtract Long (vector, by element). This instruction multiplies each vector element in the lower or upper half of the first source SIMD&FP register by the specified vector element of the second source SIMD&FP register 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 UMLSL instruction extracts vector elements from the lower half of the first source register. The UMLSL2 instruction extracts vector elements from the upper half of the first 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 | 1 | 0 | 1 | 1 | 1 | 1 | size | L | M | Rm | 0 | 1 | 1 | 0 | H | 0 | Rn | Rd | ||||||||||||
U | o2 |
constant integer idxdsize = 64 << UInt(H); integer index; bit Rmhi; case size of when '01' index = UInt(H:L:M); Rmhi = '0'; when '10' index = UInt(H:L); Rmhi = M; otherwise UNDEFINED; integer d = UInt(Rd); integer n = UInt(Rn); integer m = UInt(Rmhi:Rm); constant integer esize = 8 << UInt(size); constant integer datasize = 64; integer part = UInt(Q); integer elements = datasize DIV esize; boolean unsigned = (U == '1'); boolean sub_op = (o2 == '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
|
<Ts> |
Is an element size specifier,
encoded in
|
<index> |
Is the element index,
encoded in
|
CheckFPAdvSIMDEnabled64(); bits(datasize) operand1 = Vpart[n, part, datasize]; bits(idxdsize) operand2 = V[m, idxdsize]; bits(2*datasize) operand3 = V[d, 2*datasize]; bits(2*datasize) result; integer element1; integer element2; bits(2*esize) product; element2 = Int(Elem[operand2, index, esize], unsigned); for e = 0 to elements-1 element1 = Int(Elem[operand1, e, esize], unsigned); product = (element1*element2)<2*esize-1:0>; if sub_op then Elem[result, e, 2*esize] = Elem[operand3, e, 2*esize] - product; else Elem[result, e, 2*esize] = Elem[operand3, e, 2*esize] + product; V[d, 2*datasize] = result;
If PSTATE.DIT is 1:
Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45
Copyright © 2010-2024 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.