src/code-stubs.h

// Copyright 2006-2008 Google Inc. All Rights Reserved.
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#ifndef V8_CODE_STUBS_H_
#define V8_CODE_STUBS_H_

namespace v8 { namespace internal {


// Stub is base classes of all stubs.
class CodeStub BASE_EMBEDDED {
 public:
  enum Major {
    CallFunction,
    InlinedGenericOp,
    SmiOp,
    Compare,
    RecordWrite,  // Last stub that allows stub calls inside.
    GenericOp,
    StackCheck,
    UnarySub,
    RevertToNumber,
    CounterOp,
    ArgumentsAccess,
    Runtime,
    CEntry,
    JSEntry,
    GetProperty,   // ARM only
    SetProperty,   // ARM only
    InvokeBuiltin,  // ARM only
    JSExit,        // ARM only
    NUMBER_OF_IDS
  };

  // Retrieve the code for the stub. Generate the code if needed.
  Handle<Code> GetCode();

  static Major MajorKeyFromKey(uint32_t key) {
    return static_cast<Major>(MajorKeyBits::decode(key));
  };
  static int MinorKeyFromKey(uint32_t key) {
    return MinorKeyBits::decode(key);
  };
  static const char* MajorName(Major major_key);

  virtual ~CodeStub() {}

 private:
  // Generates the assembler code for the stub.
  virtual void Generate(MacroAssembler* masm) = 0;

  // Returns information for computing the number key.
  virtual Major MajorKey() = 0;
  virtual int MinorKey() = 0;

  // Returns a name for logging/debugging purposes.
  virtual const char* GetName() = 0;

#ifdef DEBUG
  virtual void Print() { PrintF("%s\n", GetName()); }
#endif

  // Computes the key based on major and minor.
  uint32_t GetKey() {
    ASSERT(static_cast<int>(MajorKey()) < NUMBER_OF_IDS);
    return MinorKeyBits::encode(MinorKey()) |
           MajorKeyBits::encode(MajorKey());
  }

  bool AllowsStubCalls() { return MajorKey() <= RecordWrite; }

  static const int kMajorBits = 5;
  static const int kMinorBits = kBitsPerPointer - kMajorBits - kSmiTagSize;

  class MajorKeyBits: public BitField<uint32_t, 0, kMajorBits> {};
  class MinorKeyBits: public BitField<uint32_t, kMajorBits, kMinorBits> {};

  friend class BreakPointIterator;
};

} }  // namespace v8::internal

#endif  // V8_CODE_STUBS_H_