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Re: Does neon_vset_lane<mode> expand wrong code when BYTES_BIG_ENDIAN?


On Wed, 4 Jan 2012, Xinyu Qi wrote:

> It seems these two parts of the code dealing with BYTE_BIG_ENDIAN will 
> cancel each other, and result in the original imm op unchanged.

Yes, that's correct.  Lane numbers for NEON intrinsics are the same as 
those used in assembly instructions, but for big-endian they are different 
from those used in the target-independent semantics of the RTL 
intermediate representation.

> Is there something wrong with these code?

No, see <http://gcc.gnu.org/ml/gcc-patches/2010-06/msg00409.html> where I 
explain this at greater length.

-- 
Joseph S. Myers
joseph@codesourcery.com


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