[Bug tree-optimization/80821] New: genmatch conflicting predicates

[glisse at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80821

            Bug ID: 80821
           Summary: genmatch conflicting predicates
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: glisse at gcc dot gnu.org
  Target Milestone: ---

Here is an artificial .pd file to demonstrate the issue:

(match (p1 @0) INTEGER_CST@0)
(match (p2 @0) REAL_CST@0)
(simplify (convert (p1 @0)) @0)
(simplify (convert (p2 @0)) @0)

genmatch generates a gimple_simplify_CONVERT_EXPR with twice the line

  tree op0_pops[1];

at the same level, causing a compilation error.