[PATCH] D54411: [Codegen] Merge tail blocks with no successors after block placement

[Reid Kleckner via Phabricator via llvm-commits]

rnk added inline comments.


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Comment at: lib/CodeGen/BranchFolding.cpp:1076-1077
   // First find blocks with no successors.
-  // Block placement does not create new tail merging opportunities for these
-  // blocks.
-  if (!AfterBlockPlacement) {
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The fact that you have to update so many tests shows that this comment is incorrect, at the very least.


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Comment at: test/CodeGen/X86/tail-opts.ll:589
 entry:
   %0 = icmp eq i32 undef, 0
   br i1 %0, label %bbx, label %bby
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I think we have to fix this test by replacing uses of undef with some new i32 parameter, then it will test the relevant code again.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D54411/new/

https://reviews.llvm.org/D54411