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Re: Help w/ CFG/loop optimization problem?


Hi Dale,

> Advice?

Spooky!  I posted to patch to gcc-patches to fix a similar problem
(CFG vs LOOP) less than an hour after your question.

I think I know a possible fix.  I believe that the "conditional branch
over an unconditional branch" idiom that GCC's initial RTL generation
uses is a historical artifact.  I suspect that GCC now handles long
conditional branches perfectly well,  so creating jumps over jumps
does nothing but confuse CFG, which in turn confuses LOOP.

Roger
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