diff --git a/clang/lib/CodeGen/CGObjC.cpp b/clang/lib/CodeGen/CGObjC.cpp
index f3a948cf13f9c..ccda7ce8f41b9 100644
--- a/clang/lib/CodeGen/CGObjC.cpp
+++ b/clang/lib/CodeGen/CGObjC.cpp
@@ -842,15 +842,6 @@ static void emitStructGetterCall(CodeGenFunction &CGF, ObjCIvarDecl *ivar,
                callee, ReturnValueSlot(), args);
 }
 
-/// Determine whether the given architecture supports unaligned atomic
-/// accesses.  They don't have to be fast, just faster than a function
-/// call and a mutex.
-static bool hasUnalignedAtomics(llvm::Triple::ArchType arch) {
-  // FIXME: Allow unaligned atomic load/store on x86.  (It is not
-  // currently supported by the backend.)
-  return false;
-}
-
 /// Return the maximum size that permits atomic accesses for the given
 /// architecture.
 static CharUnits getMaxAtomicAccessSize(CodeGenModule &CGM,
@@ -1023,14 +1014,6 @@ PropertyImplStrategy::PropertyImplStrategy(CodeGenModule &CGM,
   llvm::Triple::ArchType arch =
     CGM.getTarget().getTriple().getArch();
 
-  // Most architectures require memory to fit within a single cache
-  // line, so the alignment has to be at least the size of the access.
-  // Otherwise we have to grab a lock.
-  if (IvarAlignment < IvarSize && !hasUnalignedAtomics(arch)) {
-    Kind = CopyStruct;
-    return;
-  }
-
   // If the ivar's size exceeds the architecture's maximum atomic
   // access size, we have to use CopyStruct.
   if (IvarSize > getMaxAtomicAccessSize(CGM, arch)) {
diff --git a/clang/test/CodeGenObjC/objc_copyStruct.m b/clang/test/CodeGenObjC/objc_copyStruct.m
index 7bbad866e2b1f..8e52815a308ab 100644
--- a/clang/test/CodeGenObjC/objc_copyStruct.m
+++ b/clang/test/CodeGenObjC/objc_copyStruct.m
@@ -2,7 +2,7 @@
 // RUN: %clang -target x86_64-apple-ios -fobjc-runtime=ios -Wno-objc-root-class -S -o - -emit-llvm %s | FileCheck %s
 
 struct S {
-  float f, g;
+  double f, g;
 };
 
 @interface I
@@ -13,4 +13,3 @@ @implementation I
 @end
 
 // CHECK: declare {{.*}}void @objc_copyStruct(ptr, ptr, i64, i1, i1)
-
diff --git a/clang/test/CodeGenObjC/property-aggregate.m b/clang/test/CodeGenObjC/property-aggregate.m
index f4211b6b62bd5..4c8c8893f920f 100644
--- a/clang/test/CodeGenObjC/property-aggregate.m
+++ b/clang/test/CodeGenObjC/property-aggregate.m
@@ -1,13 +1,8 @@
 // RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm %s -o - | FileCheck %s
 
-// This structure's size is not a power of two, so the property does
-// not get native atomics, even though x86-64 can do unaligned atomics
-// with a lock prefix.
 struct s3 { char c[3]; };
 
 // This structure's size is, so it does, because it can.
-// FIXME: But we don't at the moment; the backend doesn't know how to generate
-// correct code.
 struct s4 { char c[4]; };
 
 @interface Test0
@@ -18,14 +13,8 @@ @implementation Test0
 @synthesize s3, s4;
 @end
 
-// CHECK: define internal i24 @"\01-[Test0 s3]"(
-// CHECK: call void @objc_copyStruct
 
-// CHECK: define internal void @"\01-[Test0 setS3:]"(
-// CHECK: call void @objc_copyStruct
 
-// CHECK: define internal i32 @"\01-[Test0 s4]"(
-// CHECK: call void @objc_copyStruct
 
-// CHECK: define internal void @"\01-[Test0 setS4:]"(
-// CHECK: call void @objc_copyStruct
+//// NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+// CHECK: {{.*}}