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Date: Mon, 18 Jul 2005 05:52:00 -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/22532] [4.1 Regression] We produce worse code on the mainline for a loop
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------- Additional Comments From pinskia at gcc dot gnu dot org  2005-07-18 05:17 -------
The reason why eustore does not remove it is because we have a loop and a PHI intbetween the load 
and store:
  #   d_15 = V_MUST_DEF <d_1>;
  d = s_2;
  #   d_18 = V_MAY_DEF <d_15>;
  f (s_9);
  #   VUSE <d_18>;
  s_16 = d;
  i_17 = i_3 + 1;

  # i_3 = PHI <i_10(0), i_17(1)>;
  # s_2 = PHI <s_8(0), s_16(1)>;
  # d_1 = PHI <d_4(0), d_18(1)>;
<L1>:;
  if (i_3 < l_11) goto <L0>; else goto <L2>;

<L2>:;
  s_12 = s_2;
  #   d_13 = V_MUST_DEF <d_1>;
  d = s_2;

See how have a PHI involved.  Maybe eustore should handle PHIs too.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22532