[Alignment] Get DataLayout::StackAlignment as Align

Summary:
Internally it is needed to know if StackAlignment is set but we can
expose it as llvm::Align.

This is 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

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67852

llvm-svn: 372585
diff --git a/llvm/lib/Target/ARM/ARMCallingConv.cpp b/llvm/lib/Target/ARM/ARMCallingConv.cpp
index 5ede7c6..92ebc54 100644
--- a/llvm/lib/Target/ARM/ARMCallingConv.cpp
+++ b/llvm/lib/Target/ARM/ARMCallingConv.cpp
@@ -193,7 +193,7 @@
   // Try to allocate a contiguous block of registers, each of the correct
   // size to hold one member.
   auto &DL = State.getMachineFunction().getDataLayout();
-  unsigned StackAlign = DL.getStackAlignment();
+  unsigned StackAlign = DL.getStackAlignment().value();
   unsigned Align = std::min(PendingMembers[0].getExtraInfo(), StackAlign);
 
   ArrayRef<MCPhysReg> RegList;