Factor out repeated code to build 'this' expressions and mark them
referenced.

llvm-svn: 361588
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 455a71b..e3286e8 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -1298,10 +1298,20 @@
   /// which the function is called.
 
   QualType ThisTy = getCurrentThisType();
-  if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use);
+  if (ThisTy.isNull())
+    return Diag(Loc, diag::err_invalid_this_use);
+  return BuildCXXThisExpr(Loc, ThisTy, /*isImplicit=*/false);
+}
 
-  CheckCXXThisCapture(Loc);
-  return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false);
+Expr *Sema::BuildCXXThisExpr(SourceLocation Loc, QualType Type,
+                             bool IsImplicit) {
+  auto *This = new (Context) CXXThisExpr(Loc, Type, IsImplicit);
+  MarkThisReferenced(This);
+  return This;
+}
+
+void Sema::MarkThisReferenced(CXXThisExpr *This) {
+  CheckCXXThisCapture(This->getExprLoc());
 }
 
 bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) {
diff --git a/clang/lib/Sema/SemaExprMember.cpp b/clang/lib/Sema/SemaExprMember.cpp
index b07bba5..3d7b8db 100644
--- a/clang/lib/Sema/SemaExprMember.cpp
+++ b/clang/lib/Sema/SemaExprMember.cpp
@@ -1092,8 +1092,7 @@
     SourceLocation Loc = R.getNameLoc();
     if (SS.getRange().isValid())
       Loc = SS.getRange().getBegin();
-    CheckCXXThisCapture(Loc);
-    BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true);
+    BaseExpr = BuildCXXThisExpr(Loc, BaseExprType, /*isImplicit=*/true);
   }
 
   // Check the use of this member.
@@ -1836,8 +1835,7 @@
     SourceLocation Loc = R.getNameLoc();
     if (SS.getRange().isValid())
       Loc = SS.getRange().getBegin();
-    CheckCXXThisCapture(Loc);
-    baseExpr = new (Context) CXXThisExpr(loc, ThisTy, /*isImplicit=*/true);
+    baseExpr = BuildCXXThisExpr(loc, ThisTy, /*isImplicit=*/true);
   }
 
   return BuildMemberReferenceExpr(baseExpr, ThisTy,
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index eadc01e..e5cbd1d 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -13910,10 +13910,8 @@
         SourceLocation Loc = MemExpr->getMemberLoc();
         if (MemExpr->getQualifier())
           Loc = MemExpr->getQualifierLoc().getBeginLoc();
-        CheckCXXThisCapture(Loc);
-        Base = new (Context) CXXThisExpr(Loc,
-                                         MemExpr->getBaseType(),
-                                         /*isImplicit=*/true);
+        Base =
+            BuildCXXThisExpr(Loc, MemExpr->getBaseType(), /*isImplicit=*/true);
       }
     } else
       Base = MemExpr->getBase();
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index c653fb1..b5114ee 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -2697,8 +2697,7 @@
   ExprResult RebuildCXXThisExpr(SourceLocation ThisLoc,
                                 QualType ThisType,
                                 bool isImplicit) {
-    getSema().CheckCXXThisCapture(ThisLoc);
-    return new (getSema().Context) CXXThisExpr(ThisLoc, ThisType, isImplicit);
+    return getSema().BuildCXXThisExpr(ThisLoc, ThisType, isImplicit);
   }
 
   /// Build a new C++ throw expression.
@@ -10355,8 +10354,9 @@
   QualType T = getSema().getCurrentThisType();
 
   if (!getDerived().AlwaysRebuild() && T == E->getType()) {
-    // Make sure that we capture 'this'.
-    getSema().CheckCXXThisCapture(E->getBeginLoc());
+    // Mark it referenced in the new context regardless.
+    // FIXME: this is a bit instantiation-specific.
+    getSema().MarkThisReferenced(E);
     return E;
   }