[PATCH] D21291: [SimplifyCFG] Range reduce switches

[silviu.baranga@arm.com via llvm-commits]

sbaranga added inline comments.

================
Comment at: lib/Transforms/Utils/SimplifyCFG.cpp:4993
@@ +4992,3 @@
+  bool HasHoles = Values.back() != SI->getNumCases() - 1;
+  if (!HasHoles)
+    // This switch is already dense.
----------------
Could you also add a test for this case?

================
Comment at: lib/Transforms/Utils/SimplifyCFG.cpp:5009
@@ +5008,3 @@
+  // We can range-reduce this switch (X) to switch (X - Base) / GCD.
+  // This should be profitable if the resulting switch has no holes -
+  // this should result in a better lowering.
----------------
If it doesn't have holes then the GCD that you are looking for should be Values[1].


Repository:
  rL LLVM

http://reviews.llvm.org/D21291