[PATCH] D34200: [PM/unswitch] Teach SimpleLoopUnswitch to do non-trivial unswitching, making it no longer even remotely simple.

[Zixuan Wu (Zeson) via Phabricator via llvm-commits]

wuzish added inline comments.


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Comment at: llvm/trunk/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp:61
+static cl::opt<bool> EnableNonTrivialUnswitch(
+    "enable-nontrivial-unswitch", cl::init(false), cl::Hidden,
+    cl::desc("Forcibly enables non-trivial loop unswitching rather than "
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wuzish wrote:
> I have a question about the default value `false` of "enable-nontrivial-unswitch". Could it be changed to `true` because it seems that it can bring much improvement of bmk when enable it. Or is there any reason to stop it?
@chandlerc @sanjoy @davide  Could you please have a look at the comment?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D34200/new/

https://reviews.llvm.org/D34200