[Bug tree-optimization/113167] New: [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[Bug tree-optimization/113167] New: [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113167

            Bug ID: 113167
           Summary: [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started
                    failing many targets after recent change
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: law at gcc dot gnu.org
  Target Milestone: ---

Many targets are now seeing this failure:

FAIL: gcc.dg/tree-ssa/gen-vect-26.c scan-tree-dump-times vect "Alignment of
access forced using peeling" 1

Which has been bisected to:

commit 01f4251b8775c832a92d55e2df57c9ac72eaceef (HEAD)
Author: Tamar Christina <tamar.christina@arm.com>
Date:   Sun Dec 24 19:18:12 2023 +0000

    middle-end: Support vectorization of loops with multiple exits.

    Hi All,

    This patch adds initial support for early break vectorization in GCC. In
other
    words it implements support for vectorization of loops with multiple exits.
    The support is added for any target that implements a vector cbranch optab,
    this includes both fully masked and non-masked targets.
[ ... ]

The regression is seen on just about every cross target I'm testing.  So just
to pick one, fr30-elf.  Since this is a scan failure, you don't need a full
toolchain to reproduce, just the compiler proper.

[Bug testsuite/113167] [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113167

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0
   Last reconfirmed|                            |2023-12-29
          Component|tree-optimization           |testsuite
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
           Keywords|                            |testsuite-fail

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Just the testcase needs to be fixed/changed and added:
  #pragma GCC novector
in front of the check loop.

Note the testcase was already failing on aarch64 which is why it was not
noticed by Tamar.

[Bug testsuite/113167] [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113167

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |pinskia at gcc dot gnu.org
             Status|NEW                         |ASSIGNED

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I will fix it (and also fix the testcase for aarch64, adding 
-mgeneral-regs-only ).

[Bug testsuite/113167] [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113167

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Oh it is not on either x86_64 or aarch64:
/* { dg-do run { target vect_cmdline_needed } } */

[Bug testsuite/113167] [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113167

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Andrew Pinski <pinskia@gcc.gnu.org>:

https://gcc.gnu.org/g:200531d5b9fb99eca2b0d6b8d1e42d176413225f

commit r14-6861-g200531d5b9fb99eca2b0d6b8d1e42d176413225f
Author: Andrew Pinski <quic_apinski@quicinc.com>
Date:   Thu Dec 28 20:26:01 2023 -0800

    Fix gen-vect-26.c testcase after loops with multiple exits [PR113167]

    This fixes the gcc.dg/tree-ssa/gen-vect-26.c testcase by adding
    `#pragma GCC novector` in front of the loop that is doing the checking
    of the result. We only want to test the first loop to see if it can be
    vectorize.

    Committed as obvious after testing on x86_64-linux-gnu with -m32.

    gcc/testsuite/ChangeLog:

            PR testsuite/113167
            * gcc.dg/tree-ssa/gen-vect-26.c: Mark the test/check loop
            as novector.

    Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>

[Bug testsuite/113167] [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113167

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|ASSIGNED                    |RESOLVED

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed.

[Bug testsuite/113167] [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[tnfchris at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113167

Tamar Christina <tnfchris at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |tnfchris at gcc dot gnu.org

--- Comment #6 from Tamar Christina <tnfchris at gcc dot gnu.org> ---
Thanks for the fix.

I suspect they'll be other target tests that fail in similar ways as well as a
side effect of abort loops being vectorizable now.

[Bug testsuite/113167] [14 Regression] gcc.dg/tree-ssa/gen-vect-26.c started failing many targets after recent change

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113167

--- Comment #7 from Jeffrey A. Law <law at gcc dot gnu.org> ---
So far that's the only fallout I've seen on the embedded targets.

The qemu emulated natives aren't running as I've got some kind of network
problem here and the workers are going offline after a few hours causing those
builds to fail.