[PATCH] D36134: [ARM] Improve loop unrolling for Cortex-M

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: lib/Target/ARM/ARMTargetTransformInfo.cpp:619
+    if (isa<SCEVCouldNotCompute>(Count) || !Count->getType()->isIntegerTy())
+      UP.DefaultUnrollRuntimeCount = 4;
+  }
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This seems like you're running into some sort of limitation of unrolling infrastructure.  Maybe we need to add a feature to unroll remainder loops?

Also, which function in the test covers this codepath?


https://reviews.llvm.org/D36134