Unsigned Multiply 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, places the results in a vector, and writes the vector to the destination SIMD&FP register. The destination vector elements are twice as long as the elements that are multiplied.
The UMULL instruction extracts vector elements from the lower half of the first source register. The UMULL2 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 | 1 | 0 | 1 | 0 | H | 0 | Rn | Rd | ||||||||||||
U |
integer idxdsize = if H == '1' then 128 else 64; 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); integer esize = 8 << UInt(size); integer datasize = 64; integer part = UInt(Q); integer elements = datasize DIV esize; 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
|
<Ts> |
Is an element size specifier,
encoded in
|
<index> |
Is the element index,
encoded in
|
CheckFPAdvSIMDEnabled64(); bits(datasize) operand1 = Vpart[n, part]; bits(idxdsize) operand2 = V[m]; 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>; Elem[result, e, 2*esize] = product; 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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