[PATCH] D132542: [InstCombine] Use dyn_cast instead of cast in visitPHINode

[Liao Chunyu via Phabricator via llvm-commits]

liaolucy added a comment.

Yes, PHI node should have first instruction as PHI.

Crash:
L3.preheader:                                     ; preds = %L3.preheader.preheader, %L2.loopexit

  %11 = zext i16 %10 to i32 -------------------------------------------------------------------------first
  %i.130 = phi i32 [ 0, %L2.loopexit ], [ %rem20.zext, %L3.preheader.preheader ]
  %tobool5.not = icmp eq i32 %i.130, 0
  br label %L3

No crash.
L3.preheader:                                     ; preds = %L3.preheader.preheader, %L2.loopexit

  %i.130 = phi i32 [ 0, %L2.loopexit ], [ %rem20.zext, %L3.preheader.preheader ]
  %11 = zext i16 %10 to i32 --------------------------------------------------------------------------change to second
  %tobool5.not = icmp eq i32 %i.130, 0
  br label %L3
   

It maybe the crash caused by this patch: https://reviews.llvm.org/D129710


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D132542/new/

https://reviews.llvm.org/D132542