diff --git a/include/llvm/IR/Attributes.h b/include/llvm/IR/Attributes.h
index 1fe1b21..e6b2804 100644
--- a/include/llvm/IR/Attributes.h
+++ b/include/llvm/IR/Attributes.h
@@ -774,12 +774,10 @@
   bool hasAlignmentAttr() const;
 
   /// Retrieve the alignment attribute, if it exists.
-  uint64_t getAlignment() const { return Alignment ? Alignment->value() : 0; }
+  MaybeAlign getAlignment() const { return Alignment; }
 
   /// Retrieve the stack alignment attribute, if it exists.
-  uint64_t getStackAlignment() const {
-    return StackAlignment ? StackAlignment->value() : 0;
-  }
+  MaybeAlign getStackAlignment() const { return StackAlignment; }
 
   /// Retrieve the number of dereferenceable bytes, if the
   /// dereferenceable attribute exists (zero is returned otherwise).
diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index 7a269ef..e58b6e9 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -140,7 +140,7 @@
       // If the alignment was parsed as an attribute, move to the alignment
       // field.
       if (FnAttrs.hasAlignmentAttr()) {
-        Fn->setAlignment(MaybeAlign(FnAttrs.getAlignment()));
+        Fn->setAlignment(FnAttrs.getAlignment());
         FnAttrs.removeAttribute(Attribute::Alignment);
       }
 
@@ -1122,9 +1122,9 @@
       if (ParseToken(lltok::StringConstant, "expected partition string"))
         return true;
     } else if (Lex.getKind() == lltok::kw_align) {
-      unsigned Alignment;
+      MaybeAlign Alignment;
       if (ParseOptionalAlignment(Alignment)) return true;
-      GV->setAlignment(MaybeAlign(Alignment));
+      GV->setAlignment(Alignment);
     } else if (Lex.getKind() == lltok::MetadataVar) {
       if (ParseGlobalObjectMetadataAttachment(*GV))
         return true;
@@ -1229,12 +1229,13 @@
       // As a hack, we allow function alignment to be initially parsed as an
       // attribute on a function declaration/definition or added to an attribute
       // group and later moved to the alignment field.
-      unsigned Alignment;
+      MaybeAlign Alignment;
       if (inAttrGrp) {
         Lex.Lex();
-        if (ParseToken(lltok::equal, "expected '=' here") ||
-            ParseUInt32(Alignment))
+        uint32_t Value = 0;
+        if (ParseToken(lltok::equal, "expected '=' here") || ParseUInt32(Value))
           return true;
+        Alignment = Align(Value);
       } else {
         if (ParseOptionalAlignment(Alignment))
           return true;
@@ -1603,7 +1604,7 @@
       continue;
     }
     case lltok::kw_align: {
-      unsigned Alignment;
+      MaybeAlign Alignment;
       if (ParseOptionalAlignment(Alignment))
         return true;
       B.addAlignmentAttr(Alignment);
@@ -1720,7 +1721,7 @@
       continue;
     }
     case lltok::kw_align: {
-      unsigned Alignment;
+      MaybeAlign Alignment;
       if (ParseOptionalAlignment(Alignment))
         return true;
       B.addAlignmentAttr(Alignment);
@@ -2069,16 +2070,19 @@
 /// ParseOptionalAlignment
 ///   ::= /* empty */
 ///   ::= 'align' 4
-bool LLParser::ParseOptionalAlignment(unsigned &Alignment) {
-  Alignment = 0;
+bool LLParser::ParseOptionalAlignment(MaybeAlign &Alignment) {
+  Alignment = None;
   if (!EatIfPresent(lltok::kw_align))
     return false;
   LocTy AlignLoc = Lex.getLoc();
-  if (ParseUInt32(Alignment)) return true;
-  if (!isPowerOf2_32(Alignment))
+  uint32_t Value = 0;
+  if (ParseUInt32(Value))
+    return true;
+  if (!isPowerOf2_32(Value))
     return Error(AlignLoc, "alignment is not a power of two");
-  if (Alignment > Value::MaximumAlignment)
+  if (Value > Value::MaximumAlignment)
     return Error(AlignLoc, "huge alignments are not supported yet");
+  Alignment = Align(Value);
   return false;
 }
 
@@ -2115,7 +2119,7 @@
 ///
 /// This returns with AteExtraComma set to true if it ate an excess comma at the
 /// end.
-bool LLParser::ParseOptionalCommaAlign(unsigned &Alignment,
+bool LLParser::ParseOptionalCommaAlign(MaybeAlign &Alignment,
                                        bool &AteExtraComma) {
   AteExtraComma = false;
   while (EatIfPresent(lltok::comma)) {
@@ -5370,7 +5374,7 @@
   LocTy BuiltinLoc;
   std::string Section;
   std::string Partition;
-  unsigned Alignment;
+  MaybeAlign Alignment;
   std::string GC;
   GlobalValue::UnnamedAddr UnnamedAddr = GlobalValue::UnnamedAddr::None;
   unsigned AddrSpace = 0;
@@ -6865,7 +6869,7 @@
 int LLParser::ParseAlloc(Instruction *&Inst, PerFunctionState &PFS) {
   Value *Size = nullptr;
   LocTy SizeLoc, TyLoc, ASLoc;
-  unsigned Alignment = 0;
+  MaybeAlign Alignment;
   unsigned AddrSpace = 0;
   Type *Ty = nullptr;
 
@@ -6913,7 +6917,8 @@
   if (Size && !Size->getType()->isIntegerTy())
     return Error(SizeLoc, "element count must have integer type");
 
-  AllocaInst *AI = new AllocaInst(Ty, AddrSpace, Size, Alignment);
+  AllocaInst *AI =
+      new AllocaInst(Ty, AddrSpace, Size, Alignment ? Alignment->value() : 0);
   AI->setUsedWithInAlloca(IsInAlloca);
   AI->setSwiftError(IsSwiftError);
   Inst = AI;
@@ -6926,7 +6931,7 @@
 ///       'singlethread'? AtomicOrdering (',' 'align' i32)?
 int LLParser::ParseLoad(Instruction *&Inst, PerFunctionState &PFS) {
   Value *Val; LocTy Loc;
-  unsigned Alignment = 0;
+  MaybeAlign Alignment;
   bool AteExtraComma = false;
   bool isAtomic = false;
   AtomicOrdering Ordering = AtomicOrdering::NotAtomic;
@@ -6964,7 +6969,8 @@
     return Error(ExplicitTypeLoc,
                  "explicit pointee type doesn't match operand's pointee type");
 
-  Inst = new LoadInst(Ty, Val, "", isVolatile, Alignment, Ordering, SSID);
+  Inst = new LoadInst(Ty, Val, "", isVolatile,
+                      Alignment ? Alignment->value() : 0, Ordering, SSID);
   return AteExtraComma ? InstExtraComma : InstNormal;
 }
 
@@ -6975,7 +6981,7 @@
 ///       'singlethread'? AtomicOrdering (',' 'align' i32)?
 int LLParser::ParseStore(Instruction *&Inst, PerFunctionState &PFS) {
   Value *Val, *Ptr; LocTy Loc, PtrLoc;
-  unsigned Alignment = 0;
+  MaybeAlign Alignment;
   bool AteExtraComma = false;
   bool isAtomic = false;
   AtomicOrdering Ordering = AtomicOrdering::NotAtomic;
@@ -7011,7 +7017,8 @@
       Ordering == AtomicOrdering::AcquireRelease)
     return Error(Loc, "atomic store cannot use Acquire ordering");
 
-  Inst = new StoreInst(Val, Ptr, isVolatile, Alignment, Ordering, SSID);
+  Inst = new StoreInst(Val, Ptr, isVolatile, Alignment ? Alignment->value() : 0,
+                       Ordering, SSID);
   return AteExtraComma ? InstExtraComma : InstNormal;
 }
 
diff --git a/lib/AsmParser/LLParser.h b/lib/AsmParser/LLParser.h
index 610e2e2..abc423b 100644
--- a/lib/AsmParser/LLParser.h
+++ b/lib/AsmParser/LLParser.h
@@ -281,14 +281,14 @@
     void ParseOptionalVisibility(unsigned &Res);
     void ParseOptionalDLLStorageClass(unsigned &Res);
     bool ParseOptionalCallingConv(unsigned &CC);
-    bool ParseOptionalAlignment(unsigned &Alignment);
+    bool ParseOptionalAlignment(MaybeAlign &Alignment);
     bool ParseOptionalDerefAttrBytes(lltok::Kind AttrKind, uint64_t &Bytes);
     bool ParseScopeAndOrdering(bool isAtomic, SyncScope::ID &SSID,
                                AtomicOrdering &Ordering);
     bool ParseScope(SyncScope::ID &SSID);
     bool ParseOrdering(AtomicOrdering &Ordering);
     bool ParseOptionalStackAlignment(unsigned &Alignment);
-    bool ParseOptionalCommaAlign(unsigned &Alignment, bool &AteExtraComma);
+    bool ParseOptionalCommaAlign(MaybeAlign &Alignment, bool &AteExtraComma);
     bool ParseOptionalCommaAddrSpace(unsigned &AddrSpace, LocTy &Loc,
                                      bool &AteExtraComma);
     bool ParseOptionalCommaInAlloca(bool &IsInAlloca);
diff --git a/lib/IR/Attributes.cpp b/lib/IR/Attributes.cpp
index 5b7b8b8..cc370e6 100644
--- a/lib/IR/Attributes.cpp
+++ b/lib/IR/Attributes.cpp
@@ -779,10 +779,12 @@
       Attr = Attribute::getWithByValType(C, B.getByValType());
       break;
     case Attribute::Alignment:
-      Attr = Attribute::getWithAlignment(C, Align(B.getAlignment()));
+      assert(B.getAlignment() && "Alignment must be set");
+      Attr = Attribute::getWithAlignment(C, *B.getAlignment());
       break;
     case Attribute::StackAlignment:
-      Attr = Attribute::getWithStackAlignment(C, Align(B.getStackAlignment()));
+      assert(B.getStackAlignment() && "StackAlignment must be set");
+      Attr = Attribute::getWithStackAlignment(C, *B.getStackAlignment());
       break;
     case Attribute::Dereferenceable:
       Attr = Attribute::getWithDereferenceableBytes(
@@ -1162,7 +1164,7 @@
   // FIXME it is not obvious how this should work for alignment. For now, say
   // we can't change a known alignment.
   const MaybeAlign OldAlign = getAttributes(Index).getAlignment();
-  unsigned NewAlign = B.getAlignment();
+  const MaybeAlign NewAlign = B.getAlignment();
   assert((!OldAlign || !NewAlign || OldAlign == NewAlign) &&
          "Attempt to change alignment!");
 #endif
@@ -1460,9 +1462,9 @@
   Attrs[Kind] = true;
 
   if (Kind == Attribute::Alignment)
-    Alignment = MaybeAlign(Attr.getAlignment());
+    Alignment = Attr.getAlignment();
   else if (Kind == Attribute::StackAlignment)
-    StackAlignment = MaybeAlign(Attr.getStackAlignment());
+    StackAlignment = Attr.getStackAlignment();
   else if (Kind == Attribute::ByVal)
     ByValType = Attr.getValueAsType();
   else if (Kind == Attribute::Dereferenceable)