[PATCH] [WinEH] Update C++ exception state numbering code

[Reid Kleckner]

REPOSITORY
  rL LLVM

================
Comment at: lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp:588
@@ +587,3 @@
+// with each action before we start assigning state numbers.
+void WinEHNumbering::findActionRootLPads(const Function &F) {
+  auto I = VisitedHandlers.insert(&F);
----------------
majnemer wrote:
> `calculateStateNumbers` does the same basic traversal, how does stashing the first landing pad associated with the action help things?  Is it just to reenable the optimization in `processCallSite` ?
Yeah, if I read this right, all the RootLPad related changes are separable and are for reducing the number of TryBlockMapEntries.

What do you think about separating the ip2state handler begin label from the rootlpad change?

http://reviews.llvm.org/D9512

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/