Clean up uses of unique_ptr for RAII objects. NFC.

- EnterExpressionEvaluationContext allows you to specify whether you
  *actually* want to enter an evaluation context.
- For types that don't allow that, llvm::Optional<Foo> should do the
  same thing as std::unique_ptr<Foo>, but with 100% less heap
  allocations.

llvm-svn: 286500

1 files changed, 9 insertions, 8 deletions

diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index f36e9dfdc44..ea942eb69a9 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -25,6 +25,7 @@
 #include "clang/Sema/PrettyDeclStackTrace.h"
 #include "clang/Sema/Scope.h"
 #include "clang/Sema/SemaDiagnostic.h"
+#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringSwitch.h"
@@ -301,10 +302,10 @@ unsigned Parser::ParseAttributeArgsCommon(
 
     // Parse the non-empty comma-separated list of expressions.
     do {
-      std::unique_ptr<EnterExpressionEvaluationContext> Unevaluated;
-      if (attributeParsedArgsUnevaluated(*AttrName))
-        Unevaluated.reset(
-            new EnterExpressionEvaluationContext(Actions, Sema::Unevaluated));
+      bool ShouldEnter = attributeParsedArgsUnevaluated(*AttrName);
+      EnterExpressionEvaluationContext Unevaluated(
+          Actions, Sema::Unevaluated, /*LambdaContextDecl=*/nullptr,
+          /*IsDecltype=*/false, ShouldEnter);
 
       ExprResult ArgExpr(
           Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression()));
@@ -366,13 +367,13 @@ void Parser::ParseGNUAttributeArgs(IdentifierInfo *AttrName,
 
   // These may refer to the function arguments, but need to be parsed early to
   // participate in determining whether it's a redeclaration.
-  std::unique_ptr<ParseScope> PrototypeScope;
+  llvm::Optional<ParseScope> PrototypeScope;
   if (normalizeAttrName(AttrName->getName()) == "enable_if" &&
       D && D->isFunctionDeclarator()) {
     DeclaratorChunk::FunctionTypeInfo FTI = D->getFunctionTypeInfo();
-    PrototypeScope.reset(new ParseScope(this, Scope::FunctionPrototypeScope |
-                                        Scope::FunctionDeclarationScope |
-                                        Scope::DeclScope));
+    PrototypeScope.emplace(this, Scope::FunctionPrototypeScope |
+                                     Scope::FunctionDeclarationScope |
+                                     Scope::DeclScope);
     for (unsigned i = 0; i != FTI.NumParams; ++i) {
       ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
       Actions.ActOnReenterCXXMethodParameter(getCurScope(), Param);