[Function builders] allowOneWay->oneWay and clean up some logic

Author: DougGregor

lib/Sema/BuilderTransform.cpp

@@ -53,7 +53,7 @@ class BuilderClosureVisitor
   Expr *buildCallIfWanted(SourceLoc loc,
                           Identifier fnName, ArrayRef<Expr *> args,
                           ArrayRef<Identifier> argLabels,
-                          bool allowOneWay) {
+                          bool oneWay) {
     if (!wantExpr)
       return nullptr;
 
@@ -87,7 +87,7 @@ class BuilderClosureVisitor
                                     /*trailing closure*/ nullptr,
                                     /*implicit*/true);
 
-    if (allowOneWay) {
+    if (oneWay) {
       // Form a one-way constraint to prevent backward propagation.
       result = new (ctx) OneWayExpr(result);
     }
@@ -173,10 +173,10 @@ class BuilderClosureVisitor
         if (builderSupports(ctx.Id_buildExpression)) {
           expr = buildCallIfWanted(expr->getLoc(), ctx.Id_buildExpression,
                                    { expr }, { Identifier() },
-                                   /*allowOneWay=*/true);
-        } else {
-          expr = new (ctx) OneWayExpr(expr);
+                                   /*oneWay=*/false);
         }
+
+        expr = new (ctx) OneWayExpr(expr);
       }
 
       expressions.push_back(expr);
@@ -186,7 +186,7 @@ class BuilderClosureVisitor
     return buildCallIfWanted(braceStmt->getStartLoc(),
                              ctx.Id_buildBlock, expressions,
                              /*argLabels=*/{ },
-                             /*allowOneWay=*/true);
+                             /*oneWay=*/true);
   }
 
   Expr *visitReturnStmt(ReturnStmt *stmt) {
@@ -212,7 +212,7 @@ class BuilderClosureVisitor
       return nullptr;
 
     return buildCallIfWanted(doStmt->getStartLoc(), ctx.Id_buildDo, arg,
-                             /*argLabels=*/{ }, /*allowOneWay=*/true);
+                             /*argLabels=*/{ }, /*oneWay=*/true);
   }
 
   CONTROL_FLOW_STMT(Yield)
@@ -299,7 +299,7 @@ class BuilderClosureVisitor
       chainExpr = buildCallIfWanted(ifStmt->getStartLoc(),
                                     ctx.Id_buildIf, chainExpr,
                                     /*argLabels=*/{ },
-                                    /*allowOneWay=*/true);
+                                    /*oneWay=*/true);
     } else {
       // Form a one-way constraint to prevent backward propagation.
       chainExpr = new (ctx) OneWayExpr(chainExpr);
@@ -423,7 +423,7 @@ class BuilderClosureVisitor
       operand = buildCallIfWanted(operand->getStartLoc(),
                                   ctx.Id_buildEither, operand,
                                   {isSecond ? ctx.Id_second : ctx.Id_first},
-                                  /*allowOneWay=*/false);
+                                  /*oneWay=*/false);
     }
 
     // Inject into Optional if required.  We'll be adding the call to