[PATCH] D65958: [Loop] Add isRotated method to Loop class.

[Michael Kruse via Phabricator via llvm-commits]

Meinersbur added inline comments.


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Comment at: llvm/include/llvm/Analysis/LoopInfo.h:763
+    BasicBlock *Latch = getLoopLatch();
+    assert(Latch && "Expecting valid latch block.");
+    return isLoopExiting(Latch);
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I think it would be simpler if the function would return `false` if there are multiple latches with the meaning that the loop is not in loop-rotated normal form.

Note that there might still be multiple exiting edges, e.g. if the latch's terminator is a switch.

I can also think a definition for rotated with multiple latches: All latches' outgoing edges that are not backedges are existing (so the property is orthogonal to simplified form), but this would probably not be useful for anything.


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Comment at: llvm/unittests/Analysis/LoopInfoTest.cpp:1214
     EXPECT_TRUE(Exits.size() == 1);
   });
 }
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[suggestion] ` EXPECT_FALSE(L->isRotated())` to have a negative test as well.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D65958/new/

https://reviews.llvm.org/D65958