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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/104276] memset is not elimited when followed by a store loop writing to that memory location
Date: Fri, 28 Jan 2022 23:40:50 +0000	[thread overview]
Message-ID: <bug-104276-4-x19wxLloWS@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-104276-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104276

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Fail to eliminate deadstore |memset is not elimited when
                   |from vector constructor     |followed by a store loop
                   |                            |writing to that memory
                   |                            |location
   Last reconfirmed|                            |2022-01-28
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Simplified C testcase (without std::vector usage):

#define SZ 4096

void foo1(int *a) {
    __builtin_memset(a, 0, sizeof(int)*SZ);
    for (int n = 0; n < SZ; ++n) {
        a[n] = n;
    }
}

  parent reply	other threads:[~2022-01-28 23:40 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-28 23:16 [Bug c++/104276] New: Fail to eliminate deadstore from vector constructor Darrell.Wright at gmail dot com
2022-01-28 23:33 ` [Bug tree-optimization/104276] " pinskia at gcc dot gnu.org
2022-01-28 23:33 ` pinskia at gcc dot gnu.org
2022-01-28 23:35 ` pinskia at gcc dot gnu.org
2022-01-28 23:37 ` Darrell.Wright at gmail dot com
2022-01-28 23:40 ` pinskia at gcc dot gnu.org [this message]
2022-01-28 23:44 ` [Bug tree-optimization/104276] memset is not elimited when followed by a store loop writing to that memory location pinskia at gcc dot gnu.org
2022-01-28 23:45 ` pinskia at gcc dot gnu.org
2022-01-31  8:15 ` rguenth at gcc dot gnu.org
2022-07-15 19:14 ` Darrell.Wright at gmail dot com

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