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Re: Some thoughts about steerring commitee work


On Fri, Jun 15, 2007 at 06:21:53PM -0700, Ian Lance Taylor wrote:
> 
> This is hardly a new thought, but I believe that for the i386 gcc is
> handicapped by reload.  No matter how smart we are before reload, it
> just take one poor decision by reload in an inner loop and we've lost
> all the gains.  Reload has enormous complexities which are mostly
> irrelevant for the i386.  And I think that the idea of doing register
> allocation separately from spill code generation does not make sense
> on the i386.
> 

Why don't we turn on vectorizer at -O3 or even -O2, depending on
ISA? I added -ftree-vectorize to BOOT_CFLAGS on x86-64. According to
-ftree-vectorizer-verbose=1, there are 82 loops vectorized in
gcc source. There are no regressions. There are not much changes
in bootstrap time as well as "make check" time.


H.J.


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