[all-commits] [llvm/llvm-project] c3b9c3: [SCCP] Propagate exact flags (#72432)

[Yingwei Zheng via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: c3b9c36f3ab4d9021951a00c9a6798e3fe0a48a5
      https://github.com/llvm/llvm-project/commit/c3b9c36f3ab4d9021951a00c9a6798e3fe0a48a5
  Author: Yingwei Zheng <dtcxzyw2333 at gmail.com>
  Date:   2023-11-16 (Thu, 16 Nov 2023)

  Changed paths:
    M llvm/lib/Transforms/Utils/SCCPSolver.cpp
    A llvm/test/Transforms/SCCP/exact-flags.ll

  Log Message:
  -----------
  [SCCP] Propagate exact flags (#72432)

This patch propagates exact flags for `ashr->lshr` and `sdiv->udiv` in
SCCP.

This missed optimization is discovered with the help of
https://github.com/AliveToolkit/alive2/pull/962.