[clang][NFC] Convert StmtDiscardKind to a scoped enum

Author: Endilll

clang/lib/Sema/TreeTransform.h

@@ -357,10 +357,10 @@ class TreeTransform {
   /// @}
 
   /// The reason why the value of a statement is not discarded, if any.
-  enum StmtDiscardKind {
-    SDK_Discarded,
-    SDK_NotDiscarded,
-    SDK_StmtExprResult,
+  enum class StmtDiscardKind {
+    Discarded,
+    NotDiscarded,
+    StmtExprResult,
   };
 
   /// Transform the given statement.
@@ -372,7 +372,8 @@ class TreeTransform {
   /// other mechanism.
   ///
   /// \returns the transformed statement.
-  StmtResult TransformStmt(Stmt *S, StmtDiscardKind SDK = SDK_Discarded);
+  StmtResult TransformStmt(Stmt *S,
+                           StmtDiscardKind SDK = StmtDiscardKind::Discarded);
 
   /// Transform the given statement.
   ///
@@ -4292,9 +4293,9 @@ StmtResult TreeTransform<Derived>::TransformStmt(Stmt *S, StmtDiscardKind SDK) {
     {
       ExprResult E = getDerived().TransformExpr(cast<Expr>(S));
 
-      if (SDK == SDK_StmtExprResult)
+      if (SDK == StmtDiscardKind::StmtExprResult)
         E = getSema().ActOnStmtExprResult(E);
-      return getSema().ActOnExprStmt(E, SDK == SDK_Discarded);
+      return getSema().ActOnExprStmt(E, SDK == StmtDiscardKind::Discarded);
     }
   }
 
@@ -8086,7 +8087,8 @@ TreeTransform<Derived>::TransformCompoundStmt(CompoundStmt *S,
   SmallVector<Stmt*, 8> Statements;
   for (auto *B : S->body()) {
     StmtResult Result = getDerived().TransformStmt(
-        B, IsStmtExpr && B == ExprResult ? SDK_StmtExprResult : SDK_Discarded);
+        B, IsStmtExpr && B == ExprResult ? StmtDiscardKind::StmtExprResult
+                                         : StmtDiscardKind::Discarded);
 
     if (Result.isInvalid()) {
       // Immediately fail if this was a DeclStmt, since it's very
@@ -9067,8 +9069,8 @@ StmtResult
 TreeTransform<Derived>::TransformObjCForCollectionStmt(
                                                   ObjCForCollectionStmt *S) {
   // Transform the element statement.
-  StmtResult Element =
-      getDerived().TransformStmt(S->getElement(), SDK_NotDiscarded);
+  StmtResult Element = getDerived().TransformStmt(
+      S->getElement(), StmtDiscardKind::NotDiscarded);
   if (Element.isInvalid())
     return StmtError();