[PATCH] D27742: CodeGen: Allow small copyable blocks to "break" the CFG.

[David Li via Phabricator via llvm-commits]

davidxl added inline comments.


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Comment at: test/CodeGen/PowerPC/tail-dup-break-cfg.ll:7
+; The code for tail-duplication during layout will produce the layout:
+; test1
+; test2
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This test demonstrates that  this patch helps when test2 is more likely (but the branch probability is not biased enough to make the successor selection to pick test2 as successor without the patch).

What happens if body1 a more likely successor such that even with the patch, body1 will be selected as test1's successor. Later when block test2 is checked, it is still beneficial to tail duplicate it. Does it happen with the patch?


https://reviews.llvm.org/D27742