2 files changed, 20 insertions, 0 deletions
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 9617de8eb7a..523e2d26247 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -583,6 +583,9 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
   if (D->hasAttr<ColdAttr>())
     F->addFnAttr(llvm::Attributes::OptimizeForSize);
 
+  if (D->hasAttr<ForceSizeOptAttr>())
+    F->addFnAttr(llvm::Attributes::ForceSizeOpt);
+
   if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
     F->setUnnamedAddr(true);
 
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index df4757e4d27..992cafce747 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -1523,6 +1523,20 @@ static void handleAliasAttr(Sema &S, Decl *D, const AttributeList &Attr) {
                                          Str->getString()));
 }
 
+static void handleForceSizeOptAttr(Sema &S, Decl *D, const AttributeList &Attr) {
+  // Check the attribute arguments.
+  if (!checkAttributeNumArgs(S, Attr, 0))
+    return;
+
+  if (!isa<FunctionDecl>(D)) {
+    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
+      << Attr.getName() << ExpectedFunction;
+    return;
+  }
+
+  D->addAttr(::new (S.Context) ForceSizeOptAttr(Attr.getRange(), S.Context));
+}
+
 static void handleColdAttr(Sema &S, Decl *D, const AttributeList &Attr) {
   // Check the attribute arguments.
   if (!checkAttributeNumArgs(S, Attr, 0))
@@ -4285,6 +4299,9 @@ static void ProcessInheritableDeclAttr(Sema &S, Scope *scope, Decl *D,
   case AttributeList::AT_ExtVectorType:
     handleExtVectorTypeAttr(S, scope, D, Attr);
     break;
+  case AttributeList::AT_ForceSizeOpt:
+    handleForceSizeOptAttr(S, D, Attr);
+    break;
   case AttributeList::AT_Format:      handleFormatAttr      (S, D, Attr); break;
   case AttributeList::AT_FormatArg:   handleFormatArgAttr   (S, D, Attr); break;
   case AttributeList::AT_CUDAGlobal:  handleGlobalAttr      (S, D, Attr); break;