[PATCH] D79605: MachineBasicBlock::updateTerminator now requires an explicit layout successor.

Tue May 12 14:32:46 PDT 2020

efriedma added a comment.

Okay, that explanation makes sense.

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Comment at: llvm/lib/CodeGen/MachineBasicBlock.cpp:586
+      // The block has an unconditional fallthrough (or the end of the block is
+      // unreachable).

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"or the end of the block is unreachable" makes me a little worried.  If I'm understanding correctly, if do somehow end up in that situation, the layout successor won't actually be a successor of the BasicBlock, and `assert(isSuccessor(PreviousLayoutSuccessor))` will fail.

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Comment at: llvm/lib/CodeGen/MachineBlockPlacement.cpp:2729
+  //   }
+  // }
+
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Commented out code?

Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D79605/new/

https://reviews.llvm.org/D79605