VDUP (scalar)

Duplicate vector element to vector duplicates a single element of a vector into every element of the destination vector.

The scalar, and the destination vector elements, can be any one of 8-bit, 16-bit, or 32-bit fields. There is no distinction between data types.

For more information about scalars see Advanced SIMD scalars.

Depending on settings in the CPACR, NSACR, and HCPTR registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be undefined, or trapped to Hyp mode. For more information see Enabling Advanced SIMD and floating-point support.

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .

A1

if imm4 IN {'x000'} then UNDEFINED; if Q == '1' && Vd<0> == '1' then UNDEFINED; integer esize; integer elements; integer index; case imm4 of when 'xxx1' esize = 8; elements = 8; index = UInt(imm4<3:1>); when 'xx10' esize = 16; elements = 4; index = UInt(imm4<3:2>); when 'x100' esize = 32; elements = 2; index = UInt(imm4<3>); d = UInt(D:Vd); m = UInt(M:Vm); regs = if Q == '0' then 1 else 2;

T1

if imm4 IN {'x000'} then UNDEFINED; if Q == '1' && Vd<0> == '1' then UNDEFINED; integer esize; integer elements; integer index; case imm4 of when 'xxx1' esize = 8; elements = 8; index = UInt(imm4<3:1>); when 'xx10' esize = 16; elements = 4; index = UInt(imm4<3:2>); when 'x100' esize = 32; elements = 2; index = UInt(imm4<3>); d = UInt(D:Vd); m = UInt(M:Vm); regs = if Q == '0' then 1 else 2;