[all-commits] [llvm/llvm-project] 32e401: [AArch64][SelectionDAG] fix infinite loop caused b...

[Fangrui Song via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 32e4013dd4003abe98d97d794600d0bd3a571018
      https://github.com/llvm/llvm-project/commit/32e4013dd4003abe98d97d794600d0bd3a571018
  Author: FLZ101 <zhangfenglei at huawei.com>
  Date:   2023-06-27 (Tue, 27 Jun 2023)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    A llvm/test/CodeGen/AArch64/dag-combine-concat-vectors.ll

  Log Message:
  -----------
  [AArch64][SelectionDAG] fix infinite loop caused by legalizing & combining CONCAT_VECTORS

Legalizing in `AArch64TargetLowering::LowerCONCAT_VECTORS()` and combining in `DAGCombiner::visitCONCAT_VECTORS()` could cause an infinite loop.
This commit fixes that issue by conditionally skipping the combining.

Fix https://github.com/llvm/llvm-project/issues/63322

Reviewed By: RKSimon, MaskRay

Differential Revision: https://reviews.llvm.org/D153316