Move the personality function from LandingPadInst to Function

The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239940 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/DwarfEHPrepare.cpp

@@ -181,27 +181,22 @@ size_t DwarfEHPrepare::pruneUnreachableResumes(
 bool DwarfEHPrepare::InsertUnwindResumeCalls(Function &Fn) {
   SmallVector<ResumeInst*, 16> Resumes;
   SmallVector<LandingPadInst*, 16> CleanupLPads;
-  bool FoundLP = false;
   for (BasicBlock &BB : Fn) {
     if (auto *RI = dyn_cast<ResumeInst>(BB.getTerminator()))
       Resumes.push_back(RI);
-    if (auto *LP = BB.getLandingPadInst()) {
+    if (auto *LP = BB.getLandingPadInst())
       if (LP->isCleanup())
         CleanupLPads.push_back(LP);
-      // Check the personality on the first landingpad. Don't do anything if
-      // it's for MSVC.
-      if (!FoundLP) {
-        FoundLP = true;
-        EHPersonality Pers = classifyEHPersonality(LP->getPersonalityFn());
-        if (isMSVCEHPersonality(Pers))
-          return false;
-      }
-    }
   }
 
   if (Resumes.empty())
     return false;
 
+  // Check the personality, don't do anything if it's for MSVC.
+  EHPersonality Pers = classifyEHPersonality(Fn.getPersonalityFn());
+  if (isMSVCEHPersonality(Pers))
+    return false;
+
   LLVMContext &Ctx = Fn.getContext();
 
   size_t ResumesLeft = pruneUnreachableResumes(Fn, Resumes, CleanupLPads);