[Bug tree-optimization/104114] New: vect.exp fails when run with -Wvector-operation-performance due to bogus diagnostics

[Bug tree-optimization/104114] New: vect.exp fails when run with -Wvector-operation-performance due to bogus diagnostics

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104114

            Bug ID: 104114
           Summary: vect.exp fails when run with
                    -Wvector-operation-performance due to bogus
                    diagnostics
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rguenth at gcc dot gnu.org
  Target Milestone: ---

On x86_64 running the vect.exp tests with additional
-Wvector-operation-performance

FAIL: gcc.dg/vect/vect-cond-11.c (test for excess errors)
FAIL: gcc.dg/vect/vect-cond-11.c -flto -ffat-lto-objects (test for excess
errors
)

which is because vector lowering diagnoses decomposing V1SImode operations
(it probably should not do that).

FAIL: gcc.dg/vect/vect-singleton_1.c (test for excess errors)
FAIL: gcc.dg/vect/vect-singleton_1.c -flto -ffat-lto-objects (test for excess
errors)

for the very same reason.

[Bug tree-optimization/104114] vect.exp fails when run with -Wvector-operation-performance due to bogus diagnostics

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104114

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot gnu.org
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2022-01-19

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
I have a patch.

[Bug tree-optimization/104114] vect.exp fails when run with -Wvector-operation-performance due to bogus diagnostics

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104114

Richard Biener <rguenth at gcc dot gnu.org> changed:

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

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed for GCC 12.

[Bug tree-optimization/104114] vect.exp fails when run with -Wvector-operation-performance due to bogus diagnostics

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104114

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:ad4188f8385f86cc04806fb0e26c7da1f5f655b8

commit r12-6755-gad4188f8385f86cc04806fb0e26c7da1f5f655b8
Author: Richard Biener <rguenther@suse.de>
Date:   Wed Jan 19 13:59:21 2022 +0100

    tree-optimization/104114 - avoid diagnosing V1mode lowering

    Currently we diagnose vector lowering of V1mode operations that
    are not natively supported into V_C_E, scalar op plus CTOR with
    -Wvector-operation-performance but that's hardly useful behavior
    even though the way we lower things can be improved.

    The following disables the diagnostics for the cases the vect.exp
    testsuite runs into, on x86 that are vect-cond-11.c and
    vect-singleton_1.c.

    2022-01-19  Richard Biener  <rguenther@suse.de>

            PR tree-optimization/104114
            * tree-vect-generic.cc (expand_vector_piecewise): Do not diagnose
            single element vector decomposition.