[csa] Return last value from BuildFastLoop to allow chaining sequential loops

src/code-stub-assembler.h

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_CODE_STUB_ASSEMBLER_H_
 #define V8_CODE_STUB_ASSEMBLER_H_
 
 #include <functional>
 
 #include "src/compiler/code-assembler.h"
@@ skipping 1055 matching lines @@
   Node* CreateWeakCellInFeedbackVector(Node* feedback_vector, Node* slot,
                                        Node* value);
 
   // Create a new AllocationSite and install it into a feedback vector.
   Node* CreateAllocationSiteInFeedbackVector(Node* feedback_vector, Node* slot);
 
   enum class IndexAdvanceMode { kPre, kPost };
 
   typedef std::function<void(Node* index)> FastLoopBody;
 
-  void BuildFastLoop(const VariableList& var_list,
-                     MachineRepresentation index_rep, Node* start_index,
-                     Node* end_index, const FastLoopBody& body, int increment,
-                     IndexAdvanceMode mode = IndexAdvanceMode::kPre);
+  Node* BuildFastLoop(const VariableList& var_list,
+                      MachineRepresentation index_rep, Node* start_index,
+                      Node* end_index, const FastLoopBody& body, int increment,
+                      IndexAdvanceMode mode = IndexAdvanceMode::kPre);
 
-  void BuildFastLoop(MachineRepresentation index_rep, Node* start_index,
-                     Node* end_index, const FastLoopBody& body, int increment,
-                     IndexAdvanceMode mode = IndexAdvanceMode::kPre) {
-    BuildFastLoop(VariableList(0, zone()), index_rep, start_index, end_index,
-                  body, increment, mode);
+  Node* BuildFastLoop(MachineRepresentation index_rep, Node* start_index,
+                      Node* end_index, const FastLoopBody& body, int increment,
+                      IndexAdvanceMode mode = IndexAdvanceMode::kPre) {
+    return BuildFastLoop(VariableList(0, zone()), index_rep, start_index,
+                         end_index, body, increment, mode);
   }
 
   enum class ForEachDirection { kForward, kReverse };
 
   typedef std::function<void(Node* fixed_array, Node* offset)>
       FastFixedArrayForEachBody;
 
   void BuildFastFixedArrayForEach(
       Node* fixed_array, ElementsKind kind, Node* first_element_inclusive,
       Node* last_element_exclusive, const FastFixedArrayForEachBody& body,
@@ skipping 208 matching lines @@
   }
 #else
 #define CSA_SLOW_ASSERT(csa, x) ((void)0)
 #endif
 
 DEFINE_OPERATORS_FOR_FLAGS(CodeStubAssembler::AllocationFlags);
 
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_CODE_STUB_ASSEMBLER_H_