[Alignment][NFC] Remove AllocaInst::setAlignment(unsigned)

Summary:
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: jholewinski, arsenm, jvesely, nhaehnle, eraman, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68141

llvm-svn: 373207
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index f40ced0..f87a6d6 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -2366,7 +2366,7 @@
             .toCharUnitsFromBits(TI.getSuitableAlign())
             .getQuantity();
     AllocaInst *AI = Builder.CreateAlloca(Builder.getInt8Ty(), Size);
-    AI->setAlignment(SuitableAlignmentInBytes);
+    AI->setAlignment(MaybeAlign(SuitableAlignmentInBytes));
     initializeAlloca(*this, AI, Size, SuitableAlignmentInBytes);
     return RValue::get(AI);
   }
@@ -2379,7 +2379,7 @@
     unsigned AlignmentInBytes =
         CGM.getContext().toCharUnitsFromBits(AlignmentInBits).getQuantity();
     AllocaInst *AI = Builder.CreateAlloca(Builder.getInt8Ty(), Size);
-    AI->setAlignment(AlignmentInBytes);
+    AI->setAlignment(MaybeAlign(AlignmentInBytes));
     initializeAlloca(*this, AI, Size, AlignmentInBytes);
     return RValue::get(AI);
   }