ARM Architecture Reference Manual ARMv7-A and ARMv7-R edition

Assembler syntax
VDUP. , Encoded as Q = 1
VDUP. , Encoded as Q = 0
where:
Instruction Details
See Standard assembler syntax fields on page A8-7. An ARM VDUP instruction must be
unconditional.
The data size. It must be one of:
8 Encoded as imm4 = '1'. imm4 encodes the index [x] of the scalar.
16 Encoded as imm4 = '10'. imm4 encodes the index [x] of the scalar.
32 Encoded as imm4 = '100'. imm4 encodes the index [x] of the scalar.
The destination vector for a quadword operation.
The destination vector for a doubleword operation.
The scalar. For details of how [x] is encoded, see the description of .
Operation
if ConditionPassed() then
EncodingSpecificOperations(); CheckAdvSIMDEnabled();
scalar = Elem[D[m],index,esize];
for r = 0 to regs-1
for e = 0 to elements-1
Elem[D[d+r],e,esize] = scalar;
Exceptions
Undefined Instruction.
ARM DDI 0406B Copyright © 1996-1998, 2000, 2004-2008 ARM Limited. All rights reserved. A8-593