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Date: Mon, 08 Aug 2005 19:54:00 -0000
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From: "pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/23286] missed fully redundant expression
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------- Additional Comments From pinskia at gcc dot gnu dot org  2005-08-08 19:54 -------
Here is a stupid testcase which can be sped up by pulling the reduandant expressions up:
int ii;
static inline int f(int i, int ii)
{
  return i/ ii;
}

int h(int) __attribute__((pure,const));

int g(int i)
{
  int j, j1 = i;
  for (j = 0; j <1000; j++)
    {
      int ii1 = ii;
      if (h(j))
        i = j1/ii1 + 2;
      else
        i = j1/ii1;
    }
  return i;
}

As we then pull the division before the loop.  As I said this was stupid as this was made up and I don't 
know how often this happens in real life.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23286