Don't track max alignment during stack object allocations since they can be deleted later. Let PEI compute it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47668 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/PrologEpilogInserter.cpp

@@ -475,8 +475,7 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
 
   // Remember the required stack alignment in case targets need it to perform
   // dynamic stack alignment.
-  assert(FFI->getMaxAlignment() == MaxAlign &&
-         "Stack alignment calculation broken!");
+  FFI->setMaxAlignment(MaxAlign);
 }