FDUP

Broadcast floating-point immediate to vector elements (unpredicated)

This instruction unconditionally broadcasts the floating-point immediate into each element of the destination vector. This instruction is unpredicated.

This instruction is used by the alias FMOV (immediate, unpredicated).

SVE
(FEAT_SVE || FEAT_SME)

313029282726252423222120191817161514131211109876543210
00100101size111001110imm8Zd
opco2

Encoding

FDUP <Zd>.<T>, #<const>

Decode for this encoding

if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; if size == '00' then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 8 << UInt(size); let d : integer = UInt(Zd); let imm : bits(esize) = VFPExpandImm{}(imm8);

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 RESERVED
01 H
10 S
11 D
<const>

Is a floating-point immediate value expressible as ±n÷16×2^r, where n and r are integers such that 16 ≤ n ≤ 31 and -3 ≤ r ≤ 4, i.e. a normalized binary floating-point encoding with 1 sign bit, 3-bit exponent, and 4-bit fractional part, encoded in the "imm8" field.

Operation

CheckSVEEnabled(); let VL : integer{} = CurrentVL(); let elements : integer = VL DIV esize; var result : bits(VL); for e = 0 to elements-1 do result[e*:esize] = imm; end; Z{VL}(d) = result;


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

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