[Bug rtl-optimization/48715] New: CASE_VALUES_THRESHOLD should be settable with --param

[Bug rtl-optimization/48715] New: CASE_VALUES_THRESHOLD should be settable with --param

[meissner at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48715

           Summary: CASE_VALUES_THRESHOLD should be settable with --param
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: rtl-optimization
        AssignedTo: meissner@gcc.gnu.org
        ReportedBy: meissner@gcc.gnu.org
              Host: powerpc64-linux
            Target: powerpc64-linux
             Build: powerpc64-linux


Created attachment 24068
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=24068
Patch to use --param to set CASE_VALUES_THRESHOLD

In looking at some improvements to the powerpc, we wanted to change the default
for when a table jump is generated vs. a series of if statements.  Now, we
could just add a powerpc specific TARGET_CASE_VALUES_THRESHOLD, but I tend to
think that these should be settable on all/most ports with --param.

At present, there are only two ports (avr and mn10300) that define their own
TARGET_CASE_VALUES_THRESHOLD hook.  My first patch does not remove the target
hook and modify the avr/mn10300 ports to use maybe_set_param_value, but that
can be done if desired.

The patch adds two --param values, one for when the port is using the casesi
insn, and the other when it uses the more primitive tablejump insn.

[Bug rtl-optimization/48715] CASE_VALUES_THRESHOLD should be settable with --param

[eric.weddington at atmel dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48715

Eric Weddington <eric.weddington at atmel dot com> changed:

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

--- Comment #1 from Eric Weddington <eric.weddington at atmel dot com> 2011-12-01 12:53:46 UTC ---
Hi Mike,

Were you planning on getting this patch in for 4.7?

[Bug rtl-optimization/48715] CASE_VALUES_THRESHOLD should be settable with --param

[meissner at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48715

Michael Meissner <meissner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.0

--- Comment #2 from Michael Meissner <meissner at gcc dot gnu.org> 2011-12-01 15:12:42 UTC ---
Patch was checked in July 5th, 2011.

[Bug rtl-optimization/48715] CASE_VALUES_THRESHOLD should be settable with --param

[gjl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48715

--- Comment #3 from Georg-Johann Lay <gjl at gcc dot gnu.org> 2011-12-01 15:36:01 UTC ---
The commit is r175878:

http://gcc.gnu.org/viewcvs?view=revision&revision=175878

There is no link-back to here because the ChangeLog does not mention the PR and
there is no commit message mentioning it.