SQABS

Signed saturating absolute value

This instruction reads each vector element from the source SIMD&FP register, puts the absolute value of the result into a vector, and writes the vector to the destination SIMD&FP register. All the values in this instruction are signed integer values.

If overflow occurs with any of the results, those results are saturated. If saturation occurs, the cumulative saturation bit FPSR.QC is set.

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.

It has encodings from 2 classes: Scalar and Vector

Scalar
(FEAT_AdvSIMD)

313029282726252423222120191817161514131211109876543210
01011110size100000011110RnRd
Uopcode

Encoding

SQABS <V><d>, <V><n>

Decode for this encoding

if !IsFeatureImplemented(FEAT_AdvSIMD) then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let esize : integer{} = 8 << UInt(size); let datasize : integer{} = esize; let elements : integer = 1;

Vector
(FEAT_AdvSIMD)

313029282726252423222120191817161514131211109876543210
0Q001110size100000011110RnRd
Uopcode

Encoding

SQABS <Vd>.<T>, <Vn>.<T>

Decode for this encoding

if !IsFeatureImplemented(FEAT_AdvSIMD) then EndOfDecode(Decode_UNDEF); end; if size::Q == '110' then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let esize : integer{} = 8 << UInt(size); let datasize : integer{} = 64 << UInt(Q); let elements : integer = datasize DIV esize;

Assembler Symbols

<V>

Is a width specifier, encoded in size:

size <V>
00 B
01 H
10 S
11 D
<d>

Is the number of the SIMD&FP destination register, encoded in the "Rd" field.

<n>

Is the number of the SIMD&FP source register, encoded in the "Rn" field.

<Vd>

Is the name of the SIMD&FP destination register, encoded in the "Rd" field.

<T>

Is an arrangement specifier, encoded in (size :: Q):

size Q <T>
00 0 8B
00 1 16B
01 0 4H
01 1 8H
10 0 2S
10 1 4S
11 0 RESERVED
11 1 2D
<Vn>

Is the name of the SIMD&FP source register, encoded in the "Rn" field.

Operation

AArch64_CheckFPAdvSIMDEnabled(); let operand : bits(datasize) = V{}(n); var result : bits(datasize); var element : integer; var sat : boolean; for e = 0 to elements-1 do element = SInt(operand[e*:esize]); element = Abs(element); (result[e*:esize], sat) = SignedSatQ{esize}(element); if sat then FPSR().QC = '1'; end; end; V{datasize}(d) = result;


2026-03_rel 2026-03-26 20:48:11

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