[Alignment][NFC] Migrate MachineFrameInfo::CreateSpillStackObject to Align

[gchatelet]

Summary

iThis patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

llvm/include/llvm/CodeGen/MachineFrameInfo.h

LLVM_ATTRIBUTE_DEPRECATED(
       "Use CreateStackObject that takes an Align instead") {
     return CreateStackObject(Size, assumeAligned(Alignment), isSpillSlot,
                              Alloca, ID);
   }
 
   /// Create a new statically sized stack object that represents a spill slot,
   /// returning a nonnegative identifier to represent it.
   int CreateSpillStackObject(uint64_t Size, Align Alignment);
-  /// FIXME: Remove this function when transition to Align is over.
-  inline int CreateSpillStackObject(uint64_t Size, unsigned Alignment) {
+  LLVM_ATTRIBUTE_DEPRECATED(
+      inline int CreateSpillStackObject(uint64_t Size, unsigned Alignment),
+      "Use CreateSpillStackObject that takes an Align instead") {
     return CreateSpillStackObject(Size, assumeAligned(Alignment));
   }
 
   /// Remove or mark dead a statically sized stack object.
   void RemoveStackObject(int ObjectIdx) {
     // Mark it dead.
     Objects[ObjectIdx+NumFixedObjects].Size = ~0ULL;
   }

llvm/lib/CodeGen/FixupStatepointCallerSaved.cpp

if (Line.Index < Line.Slots.size()) {
       // spill slot size.
       if (MFI.getObjectSize(FI) < Size) {
         MFI.setObjectSize(FI, Size);
         MFI.setObjectAlignment(FI, Align(Size));
         NumSpillSlotsExtended++;
       }
       return FI;
     }
-    int FI = MFI.CreateSpillStackObject(Size, Size);
+    int FI = MFI.CreateSpillStackObject(Size, Align(Size));
     NumSpillSlotsAllocated++;
     Line.Slots.push_back(FI);
     ++Line.Index;
     return FI;
   }
   // Sort all registers to spill in descendent order. In the
   // FixupSCSExtendSlotSize mode it will minimize the total frame size.
   // In non FixupSCSExtendSlotSize mode we can skip this step.