Re: [PATCH, committed] PR 42694: Optimize pow (x, 0.25), pow (x, 0.75), and pow (1./6.)

[Michael Meissner <meissner at linux dot vnet dot ibm dot com>]

On Wed, Apr 14, 2010 at 05:30:06PM +0200, Michael Matz wrote:
> Hi,
> 
> On Wed, 14 Apr 2010, Michael Meissner wrote:
> 
> > I committed the following patch for 42694 that adds some optimizations 
> > for pow, particularly pow (x, 0.75) that shows up in some Fortran code 
> > (bwaves).
> > 
> > The patch was discussed and approved in January when stage1 opened up: 
> > http://gcc.gnu.org/ml/gcc-patches/2010-01/msg01288.html
> 
> Have you considered to implement the transformation into the fold_builtin 
> phase, instead of into the expand_builtin phase?  That way the various 
> sqrt() calls would be exposed to the tree optimizers already which might 
> have some advantages.

Ok, sounds reasonable, and I'll think about it.  Thanks.

-- 
Michael Meissner, IBM
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