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copy each element value to ARM register

Note: This was originally posted on 25th June 2009 at http://forums.arm.com

Hello,

How to copy NEON Double word or Quad Word each element value into ARM register 's bit?

like D0 = {0,0,1,1,1,1,0,0} so R0 = 0x0000003C

Thanks

Rachit Shah over 12 years ago

Note: This was originally posted on 26th June 2009 at http://forums.arm.com

Hello sim,

Thanks,
I have checked with it and it's working fine.
Does it have any similar NEON instruction to reduce cycle time?
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Rachit Shah over 12 years ago

Note: This was originally posted on 27th June 2009 at http://forums.arm.com

Hello,
Yes , I have to extract particular bits from quad word register and insert into ARM register bit positions.
like "pmovmskb eax, xmm0" instrcution in SSE2 of x86 assembly.

Thanks
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Simon Craske over 12 years ago

Note: This was originally posted on 25th June 2009 at http://forums.arm.com

[font="Courier New"]VMOV r0,r1,d0
ORR r0,r0,r1,LSL#4
ORR r0,r0,r0,LSR#7
ORR r0,r0,r0,LSR#14
UXTB r0,r0[/font]

would be one solution.

s.
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Simon Craske over 12 years ago

Note: This was originally posted on 26th June 2009 at http://forums.arm.com

I don't believe so; does byte to bit conversion form a significant part of your algorithm?

s.
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