[PATCH] Don't check for optab for 16bit bswap

[Thomas Preud'homme]

> From: Richard Biener [mailto:rguenther@suse.de]
> Sent: Monday, December 29, 2014 5:09 PM
> 
> OK, but what about targets without a rotation optab?  Is the fallback
> expansion reasonable in all cases?

To be honest I haven't checked. I thought being a treecode means it
can always be expanded, using a sequence of shift and bitwise or if
necessary. Isn't there some language that GCC support with rotate
operators?

Given your question I guess I was wrong assuming this. Is there a list
of gimple construct that are necessary supported? What about a list
of insn pattern that a backend must necessarily provide?

Best regards,

Thomas