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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug target/105546] [11/12/13 Regression] ifconversion introduces
 many compares with loads
Date: Tue, 10 May 2022 21:02:49 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105546

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Target|                            |x86_64-linux-gnu
           Keywords|                            |missed-optimization
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-05-10
   Target Milestone|---                         |11.4
            Summary|load introduction when      |[11/12/13 Regression]
                   |initializing a struct       |ifconversion introduces
                   |                            |many compares with loads
          Component|middle-end                  |target

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This is ifconversion changing:
  if (g_344.0_1 !=3D 0)
    goto <bb 4>; [50.00%]
  else
    goto <bb 3>; [50.00%]

  <bb 3> [local count: 536870912]:

  <bb 4> [local count: 1073741824]:
  # _16 =3D PHI <4499926296329723445(2), -6(3)>
  # _18 =3D PHI <3(2), 3409572933270154779(3)>
  # _20 =3D PHI <171(2), 161(3)>
  # _22 =3D PHI <-1(2), -8(3)>
  # _24 =3D PHI <27943(2), 1(3)>
  # _26 =3D PHI <2738(2), 65526(3)>

Into straight line code but keeps the load around.

THis is a target issue.=