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References: <bug-17863-2109@http.gcc.gnu.org/bugzilla/>
Subject: [Bug tree-optimization/17863] [4.0/4.1/4.2/4.3 Regression] performance loss (not inlining as much??)
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From: "hubicka at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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------- Comment #36 from hubicka at gcc dot gnu dot org  2008-01-30 18:14 -------
Looking at the .optimized dump, one obvious problem is that we keep a lot of
pointer arithmetic that should be forward propagated:
<L147>:;
  D.184420 = *pz;
  p1 = pz + 8;
  D.184422 = *p1;
  p1 = p1 + 8;
  D.184424 = *p1;
  p1 = p1 + 8;
  D.184426 = *p1;
  p1 = p1 + 8;
  D.184428 = *p1;
  p1 = p1 + 8;
  D.184430 = *p1;
  p1 = p1 + 8;
  D.184432 = *p1;
  D.184434 = *(p1 + 8);

Those seems to be all just array manipulations.

Honza


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17863