[PATCH] D49220: [x86] Teach the EFLAGS copy lowering to handle much more complex control flow patterns including forks, merges, and even cyles.

[Eric Christopher via Phabricator via llvm-commits]

echristo accepted this revision.
echristo added a comment.

LGTM, a couple of inline requests. One small and one maybe less so.

-eric



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Comment at: llvm/lib/Target/X86/X86FlagsCopyLowering.cpp:535
+      // In most cases, we walk from the beginning to the end of the block. But
+      // when the block is the same as the copy is from, we will visit it twice.
+      // The first time we start from the copy and go to the end. The second
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"is the same" -> "is the same block" please.


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Comment at: llvm/lib/Target/X86/X86FlagsCopyLowering.cpp:539
+      // handle copies inside of cycles.
+      for (auto MII = (&UseMBB == &MBB && !VisitedBlocks.count(&UseMBB))
+                          ? std::next(CopyI->getIterator())
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The logic of these fused loop feels a bit convoluted, but I can't come up with an easy way to split it - can you?


Repository:
  rL LLVM

https://reviews.llvm.org/D49220