[Bug web/103077] New: This flag is enabled by default at -O3 and by -ftree-vectorize

[Bug web/103077] New: This flag is enabled by default at -O3 and by -ftree-vectorize

[mathieu.malaterre at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103077

            Bug ID: 103077
           Summary: This flag is enabled by default at -O3 and by
                    -ftree-vectorize
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: web
          Assignee: unassigned at gcc dot gnu.org
          Reporter: mathieu.malaterre at gmail dot com
  Target Milestone: ---

The online documentation for `-ftree-vectorize` is a bit misleading. Reading it
today:

* https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html

Gives:

[...]
-O2 turns on all optimization flags specified by -O1. It also turns on the
following optimization flags:
[...]
-ftree-loop-vectorize 
[...]
-ftree-slp-vectorize 
[...]

But later in the page:

[...]
-ftree-loop-vectorize
Perform loop vectorization on trees. This flag is enabled by default at -O3 and
by -ftree-vectorize, -fprofile-use, and -fauto-profile.

-ftree-slp-vectorize
Perform basic block vectorization on trees. This flag is enabled by default at
-O3 and by -ftree-vectorize, -fprofile-use, and -fauto-profile.
[...]

Please clarify documentation for -02 if it does turn on: -ftree-loop-vectorize
& -ftree-slp-vectorize. Thanks

[Bug tree-optimization/103077] [12 Regression] -ftree-loop-vectorize and -ftree-slp-vectorize are enabled at -O2 but their documentation says they are only enabled at -O3 and above

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103077

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-11-04
             Status|UNCONFIRMED                 |NEW
            Summary|This flag is enabled by     |[12 Regression]
                   |default at -O3 and by       |-ftree-loop-vectorize and
                   |-ftree-vectorize            |-ftree-slp-vectorize are
                   |                            |enabled at -O2 but their
                   |                            |documentation says they are
                   |                            |only enabled at -O3 and
                   |                            |above
          Component|web                         |tree-optimization
           Keywords|                            |documentation
     Ever confirmed|0                           |1
   Target Milestone|---                         |12.0

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The documentation for -ftree-slp-vectorize and -ftree-loop-vectorize was forgot
to be updated for the changes to enable it at -O2.

[Bug tree-optimization/103077] [12 Regression] -ftree-loop-vectorize and -ftree-slp-vectorize are enabled at -O2 but their documentation says they are only enabled at -O3 and above

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103077

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by hongtao Liu <liuhongt@gcc.gnu.org>:

https://gcc.gnu.org/g:ae1de0bf72fca92f94a7e29f51ce4448b877db4a

commit r12-4986-gae1de0bf72fca92f94a7e29f51ce4448b877db4a
Author: liuhongt <hongtao.liu@intel.com>
Date:   Fri Nov 5 10:41:22 2021 +0800

    Update documentation for -ftree-loop-vectorize and -ftree-slp-vectorize
which are enabled by default at -02.

    gcc/ChangeLog:

            PR tree-optimization/103077
            * doc/invoke.texi (Options That Control Optimization):
            Update documentation for -ftree-loop-vectorize and
            -ftree-slp-vectorize which are enabled by default at -02.

[Bug tree-optimization/103077] [12 Regression] -ftree-loop-vectorize and -ftree-slp-vectorize are enabled at -O2 but their documentation says they are only enabled at -O3 and above

[crazylht at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103077

Hongtao.liu <crazylht at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |crazylht at gmail dot com

--- Comment #3 from Hongtao.liu <crazylht at gmail dot com> ---
Fixed in GCC12.

[Bug tree-optimization/103077] [12 Regression] -ftree-loop-vectorize and -ftree-slp-vectorize are enabled at -O2 but their documentation says they are only enabled at -O3 and above

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103077

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

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

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
.