USQADD

Unsigned saturating addition of signed value

Add active signed elements of the source vector to the corresponding unsigned elements of the addend vector, and destructively place the results in the corresponding elements of the addend vector. Each result element is saturated to the N-bit element's unsigned integer range 0 to (2N)-1. Inactive elements in the destination vector register remain unmodified.

313029282726252423222120191817161514131211109876543210
01000100size011101100PgZmZdn
SU

USQADD <Zdn>.<T>, <Pg>/M, <Zdn>.<T>, <Zm>.<T>

if !IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer g = UInt(Pg); constant integer dn = UInt(Zdn); constant integer m = UInt(Zm);

Assembler Symbols

<Zdn>

Is the name of the first source and destination scalable vector register, encoded in the "Zdn" field.

<T>

Is the size specifier, encoded in size:

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

Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" 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 PL = VL DIV 8; constant integer elements = VL DIV esize; constant bits(PL) mask = P[g, PL]; constant bits(VL) operand1 = Z[dn, VL]; constant bits(VL) operand2 = if AnyActiveElement(mask, esize) then Z[m, VL] else Zeros(VL); bits(VL) result; for e = 0 to elements-1 constant bits(esize) element1 = Elem[operand1, e, esize]; constant bits(esize) element2 = Elem[operand2, e, esize]; if ActivePredicateElement(mask, e, esize) then Elem[result, e, esize] = UnsignedSat(UInt(element1) + SInt(element2), esize); else Elem[result, e, esize] = Elem[operand1, e, esize]; Z[dn, VL] = result;

Operational information

This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is constrained unpredictable:


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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