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From: "crazylht at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/104579] vectorizer failed to reduce max & index search together
Date: Thu, 17 Feb 2022 07:35:51 +0000	[thread overview]
Message-ID: <bug-104579-4-JdXvbMILfS@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-104579-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104579

--- Comment #2 from Hongtao.liu <crazylht at gmail dot com> ---
One possible way is sink maxInt = src[i] out of loop, when there's synchronised
index search in the loop, just like below.

int max (int *src, int n, int *position)
{
  int maxInt;
  int maxIndex;
  int i;

  maxInt = src[0];
  maxIndex = 0;
  for (i = 1; i < n; i++) {
    if (maxInt < src[i]) {
      maxIndex = i;
    }
  }
  maxInt = src[maxIndex];
  *position = maxIndex;
  return (maxInt);
}

  parent reply	other threads:[~2022-02-17  7:35 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-02-17  7:02 [Bug tree-optimization/104579] New: " crazylht at gmail dot com
2022-02-17  7:07 ` [Bug tree-optimization/104579] " crazylht at gmail dot com
2022-02-17  7:35 ` crazylht at gmail dot com [this message]
2022-02-17  8:14 ` crazylht at gmail dot com
2022-02-17 10:12 ` rguenth at gcc dot gnu.org
2022-02-17 11:15 ` crazylht at gmail dot com
2022-02-18  0:48 ` pinskia at gcc dot gnu.org

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