UMULH (unpredicated)

Unsigned multiply returning high half (unpredicated)

Widening multiply unsigned integer values of all elements of the first source vector by corresponding elements of the second source vector and place the high half of the result in the corresponding elements of the destination vector. This instruction is unpredicated.

313029282726252423222120191817161514131211109876543210
00000100size1Zm011011ZnZd
U

UMULH <Zd>.<T>, <Zn>.<T>, <Zm>.<T>

if !IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer n = UInt(Zn); constant integer m = UInt(Zm); constant integer d = UInt(Zd); constant boolean unsigned = TRUE;

Assembler Symbols

<Zd>

Is the name of the destination scalable vector register, encoded in the "Zd" field.

<T>

Is the size specifier, encoded in size:

size <T>
00 B
01 H
10 S
11 D
<Zn>

Is the name of the first source scalable vector register, encoded in the "Zn" field.

<Zm>

Is the name of the second source scalable vector register, encoded in the "Zm" field.

Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer elements = VL DIV esize; constant bits(VL) operand1 = Z[n, VL]; constant bits(VL) operand2 = Z[m, VL]; bits(VL) result; for e = 0 to elements-1 constant integer element1 = Int(Elem[operand1, e, esize], unsigned); constant integer element2 = Int(Elem[operand2, e, esize], unsigned); constant integer product = (element1 * element2) >> esize; Elem[result, e, esize] = product<esize-1:0>; Z[d, VL] = result;

Operational information

If FEAT_SVE2 is implemented or FEAT_SME is implemented, then 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

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