[turbofan] Introduce JSStackCheck operator.

src/compiler/ast-graph-builder.h

 // Copyright 2014 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_COMPILER_AST_GRAPH_BUILDER_H_
 #define V8_COMPILER_AST_GRAPH_BUILDER_H_
 
 #include "src/ast.h"
 #include "src/compiler/js-graph.h"
 
@@ skipping 242 matching lines @@
   Node* BuildHoleCheckThrow(Node* value, Variable* var, Node* not_hole,
                             BailoutId bailout_id);
 
   // Builders for non-local control flow.
   Node* BuildReturn(Node* return_value);
   Node* BuildThrow(Node* exception_value);
 
   // Builders for binary operations.
   Node* BuildBinaryOp(Node* left, Node* right, Token::Value op);
 
-  // Builder for stack-check guards.
-  Node* BuildStackCheck();
-
   // Check if the given statement is an OSR entry.
   // If so, record the stack height into the compilation and return {true}.
   bool CheckOsrEntry(IterationStatement* stmt);
 
   // Helper to wrap a Handle<T> into a Unique<T>.
   template <class T>
   Unique<T> MakeUnique(Handle<T> object) {
     return Unique<T>::CreateUninitialized(object);
   }
 
@@ skipping 204 matching lines @@
 
   // Prepare environment to be used as loop header.
   void PrepareForLoop(BitVector* assigned, bool is_osr = false);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_AST_GRAPH_BUILDER_H_