[PATCH] D21720: Unroll for uncountable loops

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

The use of the "Force" bit here is still really confusing... we need a better way of expressing the profitability of unrolling.



================
Comment at: include/llvm/CodeGen/BasicTTIImpl.h:332
+    if (L->getSubLoops().size() == 0 && TM.getOptLevel() > CodeGenOpt::Default)
+      UP.Force = true;
+
----------------
What effect does this have on performance?


Repository:
  rL LLVM

https://reviews.llvm.org/D21720