Port of fast-case switch to ARM

src/codegen.h

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 148 matching lines @@
   // Support for accessing the value field of an object (used by Date).
   virtual void GenerateValueOf(ZoneList<Expression*>* args) = 0;
   virtual void GenerateSetValueOf(ZoneList<Expression*>* args) = 0;
 
   // Fast support for charCodeAt(n).
   virtual void GenerateFastCharCodeAt(ZoneList<Expression*>* args) = 0;
 
   // Fast support for object equality testing.
   virtual void GenerateObjectEquals(ZoneList<Expression*>* args) = 0;
 
+
+  // Multiple methods for fast case switch statement support.
+
+  // The limit of the range of a fast-case switch, as a factor of the number
+  // of cases of the switch. Each platform should return a value that
+  // is optimal compared to the default code generated for a switch statement
+  // on that platform.
+  virtual int FastCaseSwitchMaxOverheadFactor() = 0;
+
+  // The minimal number of cases in a switch before the fast-case switch
+  // optimization is enabled. Each platform should return a value that
+  // is optimal compared to the default code generated for a switch statement
+  // on that platform.
+  virtual int FastCaseSwitchMinCaseCount() = 0;
+
+  // Allocate a jump table and create code to jump through it.
+  // Should call GenerateFastCaseSwitchCases to generate the code for
+  // all the cases at the appropriate point.
+  virtual void GenerateFastCaseSwitchJumpTable(
+      SwitchStatement* node, int min_index, int range, Label *fail_label,
+      SmartPointer<Label*> &case_targets, SmartPointer<Label>& case_labels) = 0;
+
+  // Generate the code for cases for the fast case switch.
+  // Called by GenerateFastCaseSwitchJumpTable.
+  virtual void GenerateFastCaseSwitchCases(
+      SwitchStatement* node, SmartPointer<Label> &case_labels);
+
+  // Fast support for constant-Smi switches.
+  virtual void GenerateFastCaseSwitchStatement(
+      SwitchStatement *node, int min_index, int range, int default_index);
+
+  // Fast support for constant-Smi switches. Tests whether switch statement
+  // permits optimization and calls GenerateFastCaseSwitch if it does.
+  // Returns true if the fast-case switch was generated, and false if not.
+  virtual bool TryGenerateFastCaseSwitchStatement(SwitchStatement *node);
+
+
  private:
   bool is_eval_;  // Tells whether code is generated for eval.
   Handle<Script> script_;
   List<DeferredCode*> deferred_;
 };
 
 
-// RuntimeStub models code stubs calling entrypoints in the Runtime class.
+// RuntimeStub models code stubs calling entry points in the Runtime class.
 class RuntimeStub : public CodeStub {
  public:
   explicit RuntimeStub(Runtime::FunctionId id, int num_arguments)
       : id_(id), num_arguments_(num_arguments) { }
 
   void Generate(MacroAssembler* masm);
 
   // Disassembler support.  It is useful to be able to print the name
   // of the runtime function called through this stub.
   static const char* GetNameFromMinorKey(int minor_key) {
@@ skipping 115 matching lines @@
   int MinorKey() { return 1; }
 
   const char* GetName() { return "JSConstructEntryStub"; }
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CODEGEN_H_