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Re: [PATCH] Fix PR63259: bswap not recognized when finishing with rotation


On Wed, Oct 08, 2014 at 02:56:46PM +0800, Thomas Preud'homme wrote:
> > From: gcc-patches-owner@gcc.gnu.org [mailto:gcc-patches-
> > owner@gcc.gnu.org] On Behalf Of Thomas Preud'homme
> > Sent: Wednesday, October 08, 2014 2:43 PM
> > > Also, perhaps you could short-circuit this if the rotation isn't by constant
> 
> Note that do_shift_rotate already check for this. Is it enough?

The question is only about the compile time cost needed through all the
routines find_bswap_or_nop calls before it finds out it can't do anything
with the rotate, the short-circuiting could avoid that.  E.g.
find_bswap_or_nop_1 first recurses on the argument etc.

	Jakub


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