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vqrshrn.u16 d0, q1, #0 instruction do not exists anymore

Note: This was originally posted on 10th September 2012 at http://forums.arm.com

Hi.

I have a small problem. xcode 4.4.1 do not accept those 2 instructions anymore


vqrshrn.u16  d0, q1, #0
vshrn.u16  d6, q3, #0

The problem comes from the immédiat value (#0)

I've had to replace those line by


vmovn.u16  d0, q1
vmovn.u16  d6, q3

But if vmovn is equivalent to vshrn, it is not really the same thing for vqrshrn !!!

I wonder if it could be a missing compilation option !

Etienne SOBOLE over 12 years ago

Note: This was originally posted on 11th September 2012 at http://forums.arm.com

The Architecture Reference Manual states that "VSHRN #0" is a synonym for "VMOVN", and that "VQSHRN #0" is a synonym for "VQMOVN".

Hum, thank you. I did not see the last line of the doc !
And I did not know the VQMOVN instruction

That's nice !
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Simon Craske over 12 years ago

Note: This was originally posted on 10th September 2012 at http://forums.arm.com

The Architecture Reference Manual states that "VSHRN #0" is a synonym for "VMOVN", and that "VQSHRN #0" is a synonym for "VQMOVN".

hth
s.
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Simon Craske over 12 years ago

Note: This was originally posted on 10th September 2012 at http://forums.arm.com

"VQRSHRN #0" can be considered as "VQSHRN #0" as there will be no fractional bits to round.

s.
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