[turbofan] Decouple inlining and native context specialization.

src/compiler/js-global-object-specialization.h

 // Copyright 2015 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_JS_GLOBAL_OBJECT_SPECIALIZATION_H_
 #define V8_COMPILER_JS_GLOBAL_OBJECT_SPECIALIZATION_H_
 
 #include "src/base/flags.h"
 #include "src/compiler/graph-reducer.h"
 
 namespace v8 {
 namespace internal {
 
 // Forward declarations.
 class CompilationDependencies;
-class ScriptContextTable;
 class TypeCache;
 
 
 namespace compiler {
 
 // Forward declarations.
 class CommonOperatorBuilder;
 class JSGraph;
 class JSOperatorBuilder;
 class SimplifiedOperatorBuilder;
 
 
 // Specializes a given JSGraph to a given global object, potentially constant
 // folding some {JSLoadGlobal} nodes or strength reducing some {JSStoreGlobal}
 // nodes.
 class JSGlobalObjectSpecialization final : public AdvancedReducer {
  public:
   // Flags that control the mode of operation.
   enum Flag {
     kNoFlags = 0u,
     kDeoptimizationEnabled = 1u << 0,
   };
   typedef base::Flags<Flag> Flags;
 
   JSGlobalObjectSpecialization(Editor* editor, JSGraph* jsgraph, Flags flags,
-                               Handle<JSGlobalObject> global_object,
+                               MaybeHandle<Context> native_context,
                                CompilationDependencies* dependencies);
 
   Reduction Reduce(Node* node) final;
 
  private:
   Reduction ReduceJSLoadGlobal(Node* node);
   Reduction ReduceJSStoreGlobal(Node* node);
 
+  // Retrieve the global object from the given {node} if known.
+  MaybeHandle<JSGlobalObject> GetGlobalObject(Node* node);
+
   struct ScriptContextTableLookupResult;
-  bool LookupInScriptContextTable(Handle<Name> name,
+  bool LookupInScriptContextTable(Handle<JSGlobalObject> global_object,
+                                  Handle<Name> name,
                                   ScriptContextTableLookupResult* result);
 
   Graph* graph() const;
   JSGraph* jsgraph() const { return jsgraph_; }
   Isolate* isolate() const;
   CommonOperatorBuilder* common() const;
   JSOperatorBuilder* javascript() const;
   SimplifiedOperatorBuilder* simplified() const;
   Flags flags() const { return flags_; }
-  Handle<JSGlobalObject> global_object() const { return global_object_; }
-  Handle<ScriptContextTable> script_context_table() const {
-    return script_context_table_;
-  }
+  MaybeHandle<Context> native_context() const { return native_context_; }
   CompilationDependencies* dependencies() const { return dependencies_; }
 
   JSGraph* const jsgraph_;
   Flags const flags_;
-  Handle<JSGlobalObject> global_object_;
-  Handle<ScriptContextTable> script_context_table_;
+  MaybeHandle<Context> native_context_;
   CompilationDependencies* const dependencies_;
   TypeCache const& type_cache_;
 
   DISALLOW_COPY_AND_ASSIGN(JSGlobalObjectSpecialization);
 };
 
 DEFINE_OPERATORS_FOR_FLAGS(JSGlobalObjectSpecialization::Flags)
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_JS_GLOBAL_OBJECT_SPECIALIZATION_H_