[all-commits] [llvm/llvm-project] 00396e: [ConstraintElim] Support arbitrary incoming values...

[Florian Hahn via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 00396e6a1a0b79fda008cb4e86b616d7952b33c8
      https://github.com/llvm/llvm-project/commit/00396e6a1a0b79fda008cb4e86b616d7952b33c8
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2023-10-03 (Tue, 03 Oct 2023)

  Changed paths:
    M llvm/lib/Transforms/Scalar/ConstraintElimination.cpp
    M llvm/test/Transforms/ConstraintElimination/monotonic-int-phis-nested-loops.ll

  Log Message:
  -----------
  [ConstraintElim] Support arbitrary incoming values for inductions (#68032)

Support arbitray incoming values for AddRecs by getting the loop
predecessor and checking if its SCEV matches the AddRec start.

This is done after the existing check, which can help to catch cases
where the expression gets simplified by SCEV to either an IR constant or
existing value which can be used instead.