[Bug tree-optimization/69950] New: Allow more than one exit phi for reduction in try_create_reduction_list

[vries at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69950

            Bug ID: 69950
           Summary: Allow more than one exit phi for reduction in
                    try_create_reduction_list
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: vries at gcc dot gnu.org
  Target Milestone: ---

Here ( https://gcc.gnu.org/ml/gcc-patches/2016-01/msg00517.html ) we fix
PR69039: "Only allow single exit phi for reduction in
try_create_reduction_list" conservatively.

We want to fix it optimally, by allowing more than one exit phi with the same
value (or to merge them before).