type.hpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
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 *
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_OPTO_TYPE_HPP
#define SHARE_OPTO_TYPE_HPP

#include "opto/adlcVMDeps.hpp"
#include "runtime/handles.hpp"

// Portions of code courtesy of Clifford Click

// Optimization - Graph Style


// This class defines a Type lattice.  The lattice is used in the constant
// propagation algorithms, and for some type-checking of the iloc code.
// Basic types include RSD's (lower bound, upper bound, stride for integers),
// float & double precision constants, sets of data-labels and code-labels.
// The complete lattice is described below.  Subtypes have no relationship to
// up or down in the lattice; that is entirely determined by the behavior of
// the MEET/JOIN functions.

class Dict;
class Type;
class   TypeD;
class   TypeF;
class   TypeInt;
class   TypeLong;
class   TypeNarrowPtr;
class     TypeNarrowOop;
class     TypeNarrowKlass;
class   TypeAry;
class   TypeTuple;
class   TypeVect;
class     TypeVectS;
class     TypeVectD;
class     TypeVectX;
class     TypeVectY;
class     TypeVectZ;
class   TypePtr;
class     TypeRawPtr;
class     TypeOopPtr;
class       TypeInstPtr;
class       TypeAryPtr;
class     TypeKlassPtr;
class     TypeMetadataPtr;

//------------------------------Type-------------------------------------------
// Basic Type object, represents a set of primitive Values.
// Types are hash-cons'd into a private class dictionary, so only one of each
// different kind of Type exists.  Types are never modified after creation, so
// all their interesting fields are constant.
class Type {
  friend class VMStructs;

public:
  enum TYPES {
    Bad=0,                      // Type check
    Control,                    // Control of code (not in lattice)
    Top,                        // Top of the lattice
    Int,                        // Integer range (lo-hi)
    Long,                       // Long integer range (lo-hi)
    Half,                       // Placeholder half of doubleword
    NarrowOop,                  // Compressed oop pointer
    NarrowKlass,                // Compressed klass pointer

    Tuple,                      // Method signature or object layout
    Array,                      // Array types
    VectorS,                    //  32bit Vector types
    VectorD,                    //  64bit Vector types
    VectorX,                    // 128bit Vector types
    VectorY,                    // 256bit Vector types
    VectorZ,                    // 512bit Vector types

    AnyPtr,                     // Any old raw, klass, inst, or array pointer
    RawPtr,                     // Raw (non-oop) pointers
    OopPtr,                     // Any and all Java heap entities
    InstPtr,                    // Instance pointers (non-array objects)
    AryPtr,                     // Array pointers
    // (Ptr order matters:  See is_ptr, isa_ptr, is_oopptr, isa_oopptr.)

    MetadataPtr,                // Generic metadata
    KlassPtr,                   // Klass pointers

    Function,                   // Function signature
    Abio,                       // Abstract I/O
    Return_Address,             // Subroutine return address
    Memory,                     // Abstract store
    FloatTop,                   // No float value
    FloatCon,                   // Floating point constant
    FloatBot,                   // Any float value
    DoubleTop,                  // No double value
    DoubleCon,                  // Double precision constant
    DoubleBot,                  // Any double value
    Bottom,                     // Bottom of lattice
    lastype                     // Bogus ending type (not in lattice)
  };

  // Signal values for offsets from a base pointer
  enum OFFSET_SIGNALS {
    OffsetTop = -2000000000,    // undefined offset
    OffsetBot = -2000000001     // any possible offset
  };

  // Min and max WIDEN values.
  enum WIDEN {
    WidenMin = 0,
    WidenMax = 3
  };

private:
  typedef struct {
    TYPES                dual_type;
    BasicType            basic_type;
    const char*          msg;
    bool                 isa_oop;
    uint                 ideal_reg;
    relocInfo::relocType reloc;
  } TypeInfo;

  // Dictionary of types shared among compilations.
  static Dict* _shared_type_dict;
  static const TypeInfo _type_info[];

  static int uhash( const Type *const t );
  // Structural equality check.  Assumes that cmp() has already compared
  // the _base types and thus knows it can cast 't' appropriately.
  virtual bool eq( const Type *t ) const;

  // Top-level hash-table of types
  static Dict *type_dict() {
    return Compile::current()->type_dict();
  }

  // DUAL operation: reflect around lattice centerline.  Used instead of
  // join to ensure my lattice is symmetric up and down.  Dual is computed
  // lazily, on demand, and cached in _dual.
  const Type *_dual;            // Cached dual value
  // Table for efficient dualing of base types
  static const TYPES dual_type[lastype];

#ifdef ASSERT
  // One type is interface, the other is oop
  virtual bool interface_vs_oop_helper(const Type *t) const;
#endif

  const Type *meet_helper(const Type *t, bool include_speculative) const;

protected:
  // Each class of type is also identified by its base.
  const TYPES _base;            // Enum of Types type

  Type( TYPES t ) : _dual(NULL),  _base(t) {} // Simple types
  // ~Type();                   // Use fast deallocation
  const Type *hashcons();       // Hash-cons the type
  virtual const Type *filter_helper(const Type *kills, bool include_speculative) const;
  const Type *join_helper(const Type *t, bool include_speculative) const {
    return dual()->meet_helper(t->dual(), include_speculative)->dual();
  }

public:

  inline void* operator new( size_t x ) throw() {
    Compile* compile = Compile::current();
    compile->set_type_last_size(x);
    return compile->type_arena()->Amalloc_D(x);
  }
  inline void operator delete( void* ptr ) {
    Compile* compile = Compile::current();
    compile->type_arena()->Afree(ptr,compile->type_last_size());
  }

  // Initialize the type system for a particular compilation.
  static void Initialize(Compile* compile);

  // Initialize the types shared by all compilations.
  static void Initialize_shared(Compile* compile);

  TYPES base() const {
    assert(_base > Bad && _base < lastype, "sanity");
    return _base;
  }

  // Create a new hash-consd type
  static const Type *make(enum TYPES);
  // Test for equivalence of types
  static int cmp( const Type *const t1, const Type *const t2 );
  // Test for higher or equal in lattice
  // Variant that drops the speculative part of the types
  bool higher_equal(const Type *t) const {
    return !cmp(meet(t),t->remove_speculative());
  }
  // Variant that keeps the speculative part of the types
  bool higher_equal_speculative(const Type *t) const {
    return !cmp(meet_speculative(t),t);
  }

  // MEET operation; lower in lattice.
  // Variant that drops the speculative part of the types
  const Type *meet(const Type *t) const {
    return meet_helper(t, false);
  }
  // Variant that keeps the speculative part of the types
  const Type *meet_speculative(const Type *t) const {
    return meet_helper(t, true)->cleanup_speculative();
  }
  // WIDEN: 'widens' for Ints and other range types
  virtual const Type *widen( const Type *old, const Type* limit ) const { return this; }
  // NARROW: complement for widen, used by pessimistic phases
  virtual const Type *narrow( const Type *old ) const { return this; }

  // DUAL operation: reflect around lattice centerline.  Used instead of
  // join to ensure my lattice is symmetric up and down.
  const Type *dual() const { return _dual; }

  // Compute meet dependent on base type
  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.

  // JOIN operation; higher in lattice.  Done by finding the dual of the
  // meet of the dual of the 2 inputs.
  // Variant that drops the speculative part of the types
  const Type *join(const Type *t) const {
    return join_helper(t, false);
  }
  // Variant that keeps the speculative part of the types
  const Type *join_speculative(const Type *t) const {
    return join_helper(t, true)->cleanup_speculative();
  }

  // Modified version of JOIN adapted to the needs Node::Value.
  // Normalizes all empty values to TOP.  Does not kill _widen bits.
  // Currently, it also works around limitations involving interface types.
  // Variant that drops the speculative part of the types
  const Type *filter(const Type *kills) const {
    return filter_helper(kills, false);
  }
  // Variant that keeps the speculative part of the types
  const Type *filter_speculative(const Type *kills) const {
    return filter_helper(kills, true)->cleanup_speculative();
  }

#ifdef ASSERT
  // One type is interface, the other is oop
  virtual bool interface_vs_oop(const Type *t) const;
#endif

  // Returns true if this pointer points at memory which contains a
  // compressed oop references.
  bool is_ptr_to_narrowoop() const;
  bool is_ptr_to_narrowklass() const;

  bool is_ptr_to_boxing_obj() const;


  // Convenience access
  float getf() const;
  double getd() const;

  const TypeInt    *is_int() const;
  const TypeInt    *isa_int() const;             // Returns NULL if not an Int
  const TypeLong   *is_long() const;
  const TypeLong   *isa_long() const;            // Returns NULL if not a Long
  const TypeD      *isa_double() const;          // Returns NULL if not a Double{Top,Con,Bot}
  const TypeD      *is_double_constant() const;  // Asserts it is a DoubleCon
  const TypeD      *isa_double_constant() const; // Returns NULL if not a DoubleCon
  const TypeF      *isa_float() const;           // Returns NULL if not a Float{Top,Con,Bot}
  const TypeF      *is_float_constant() const;   // Asserts it is a FloatCon
  const TypeF      *isa_float_constant() const;  // Returns NULL if not a FloatCon
  const TypeTuple  *is_tuple() const;            // Collection of fields, NOT a pointer
  const TypeAry    *is_ary() const;              // Array, NOT array pointer
  const TypeAry    *isa_ary() const;             // Returns NULL of not ary
  const TypeVect   *is_vect() const;             // Vector
  const TypeVect   *isa_vect() const;            // Returns NULL if not a Vector
  const TypePtr    *is_ptr() const;              // Asserts it is a ptr type
  const TypePtr    *isa_ptr() const;             // Returns NULL if not ptr type
  const TypeRawPtr *isa_rawptr() const;          // NOT Java oop
  const TypeRawPtr *is_rawptr() const;           // Asserts is rawptr
  const TypeNarrowOop  *is_narrowoop() const;    // Java-style GC'd pointer
  const TypeNarrowOop  *isa_narrowoop() const;   // Returns NULL if not oop ptr type
  const TypeNarrowKlass *is_narrowklass() const; // compressed klass pointer
  const TypeNarrowKlass *isa_narrowklass() const;// Returns NULL if not oop ptr type
  const TypeOopPtr   *isa_oopptr() const;        // Returns NULL if not oop ptr type
  const TypeOopPtr   *is_oopptr() const;         // Java-style GC'd pointer
  const TypeInstPtr  *isa_instptr() const;       // Returns NULL if not InstPtr
  const TypeInstPtr  *is_instptr() const;        // Instance
  const TypeAryPtr   *isa_aryptr() const;        // Returns NULL if not AryPtr
  const TypeAryPtr   *is_aryptr() const;         // Array oop

  const TypeMetadataPtr   *isa_metadataptr() const;   // Returns NULL if not oop ptr type
  const TypeMetadataPtr   *is_metadataptr() const;    // Java-style GC'd pointer
  const TypeKlassPtr      *isa_klassptr() const;      // Returns NULL if not KlassPtr
  const TypeKlassPtr      *is_klassptr() const;       // assert if not KlassPtr

  virtual bool      is_finite() const;           // Has a finite value
  virtual bool      is_nan()    const;           // Is not a number (NaN)

  // Returns this ptr type or the equivalent ptr type for this compressed pointer.
  const TypePtr* make_ptr() const;

  // Returns this oopptr type or the equivalent oopptr type for this compressed pointer.
  // Asserts if the underlying type is not an oopptr or narrowoop.
  const TypeOopPtr* make_oopptr() const;

  // Returns this compressed pointer or the equivalent compressed version
  // of this pointer type.
  const TypeNarrowOop* make_narrowoop() const;

  // Returns this compressed klass pointer or the equivalent
  // compressed version of this pointer type.
  const TypeNarrowKlass* make_narrowklass() const;

  // Special test for register pressure heuristic
  bool is_floatingpoint() const;        // True if Float or Double base type

  // Do you have memory, directly or through a tuple?
  bool has_memory( ) const;

  // TRUE if type is a singleton
  virtual bool singleton(void) const;

  // TRUE if type is above the lattice centerline, and is therefore vacuous
  virtual bool empty(void) const;

  // Return a hash for this type.  The hash function is public so ConNode
  // (constants) can hash on their constant, which is represented by a Type.
  virtual int hash() const;

  // Map ideal registers (machine types) to ideal types
  static const Type *mreg2type[];

  // Printing, statistics
#ifndef PRODUCT
  void         dump_on(outputStream *st) const;
  void         dump() const {
    dump_on(tty);
  }
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
  static  void dump_stats();

  static const char* str(const Type* t);
#endif
  void typerr(const Type *t) const; // Mixing types error

  // Create basic type
  static const Type* get_const_basic_type(BasicType type) {
    assert((uint)type <= T_CONFLICT && _const_basic_type[type] != NULL, "bad type");
    return _const_basic_type[type];
  }

  // For two instance arrays of same dimension, return the base element types.
  // Otherwise or if the arrays have different dimensions, return NULL.
  static void get_arrays_base_elements(const Type *a1, const Type *a2,
                                       const TypeInstPtr **e1, const TypeInstPtr **e2);

  // Mapping to the array element's basic type.
  BasicType array_element_basic_type() const;

  // Create standard type for a ciType:
  static const Type* get_const_type(ciType* type);

  // Create standard zero value:
  static const Type* get_zero_type(BasicType type) {
    assert((uint)type <= T_CONFLICT && _zero_type[type] != NULL, "bad type");
    return _zero_type[type];
  }

  // Report if this is a zero value (not top).
  bool is_zero_type() const {
    BasicType type = basic_type();
    if (type == T_VOID || type >= T_CONFLICT)
      return false;
    else
      return (this == _zero_type[type]);
  }

  // Convenience common pre-built types.
  static const Type *ABIO;
  static const Type *BOTTOM;
  static const Type *CONTROL;
  static const Type *DOUBLE;
  static const Type *FLOAT;
  static const Type *HALF;
  static const Type *MEMORY;
  static const Type *MULTI;
  static const Type *RETURN_ADDRESS;
  static const Type *TOP;

  // Mapping from compiler type to VM BasicType
  BasicType basic_type() const       { return _type_info[_base].basic_type; }
  uint ideal_reg() const             { return _type_info[_base].ideal_reg; }
  const char* msg() const            { return _type_info[_base].msg; }
  bool isa_oop_ptr() const           { return _type_info[_base].isa_oop; }
  relocInfo::relocType reloc() const { return _type_info[_base].reloc; }

  // Mapping from CI type system to compiler type:
  static const Type* get_typeflow_type(ciType* type);

  static const Type* make_from_constant(ciConstant constant,
                                        bool require_constant = false,
                                        int stable_dimension = 0,
                                        bool is_narrow = false,
                                        bool is_autobox_cache = false);

  static const Type* make_constant_from_field(ciInstance* holder,
                                              int off,
                                              bool is_unsigned_load,
                                              BasicType loadbt);

  static const Type* make_constant_from_field(ciField* field,
                                              ciInstance* holder,
                                              BasicType loadbt,
                                              bool is_unsigned_load);

  static const Type* make_constant_from_array_element(ciArray* array,
                                                      int off,
                                                      int stable_dimension,
                                                      BasicType loadbt,
                                                      bool is_unsigned_load);

  // Speculative type helper methods. See TypePtr.
  virtual const TypePtr* speculative() const                                  { return NULL; }
  virtual ciKlass* speculative_type() const                                   { return NULL; }
  virtual ciKlass* speculative_type_not_null() const                          { return NULL; }
  virtual bool speculative_maybe_null() const                                 { return true; }
  virtual bool speculative_always_null() const                                { return true; }
  virtual const Type* remove_speculative() const                              { return this; }
  virtual const Type* cleanup_speculative() const                             { return this; }
  virtual bool would_improve_type(ciKlass* exact_kls, int inline_depth) const { return exact_kls != NULL; }
  virtual bool would_improve_ptr(ProfilePtrKind ptr_kind) const { return ptr_kind == ProfileAlwaysNull || ptr_kind == ProfileNeverNull; }
  const Type* maybe_remove_speculative(bool include_speculative) const;

  virtual bool maybe_null() const { return true; }
  virtual bool is_known_instance() const { return false; }

private:
  // support arrays
  static const Type*        _zero_type[T_CONFLICT+1];
  static const Type* _const_basic_type[T_CONFLICT+1];
};

//------------------------------TypeF------------------------------------------
// Class of Float-Constant Types.
class TypeF : public Type {
  TypeF( float f ) : Type(FloatCon), _f(f) {};
public:
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous
public:
  const float _f;               // Float constant

  static const TypeF *make(float f);

  virtual bool        is_finite() const;  // Has a finite value
  virtual bool        is_nan()    const;  // Is not a number (NaN)

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.
  // Convenience common pre-built types.
  static const TypeF *ZERO; // positive zero only
  static const TypeF *ONE;
  static const TypeF *POS_INF;
  static const TypeF *NEG_INF;
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
#endif
};

//------------------------------TypeD------------------------------------------
// Class of Double-Constant Types.
class TypeD : public Type {
  TypeD( double d ) : Type(DoubleCon), _d(d) {};
public:
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous
public:
  const double _d;              // Double constant

  static const TypeD *make(double d);

  virtual bool        is_finite() const;  // Has a finite value
  virtual bool        is_nan()    const;  // Is not a number (NaN)

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.
  // Convenience common pre-built types.
  static const TypeD *ZERO; // positive zero only
  static const TypeD *ONE;
  static const TypeD *POS_INF;
  static const TypeD *NEG_INF;
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
#endif
};

//------------------------------TypeInt----------------------------------------
// Class of integer ranges, the set of integers between a lower bound and an
// upper bound, inclusive.
class TypeInt : public Type {
  TypeInt( jint lo, jint hi, int w );
protected:
  virtual const Type *filter_helper(const Type *kills, bool include_speculative) const;

public:
  typedef jint NativeType;
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous
  const jint _lo, _hi;          // Lower bound, upper bound
  const short _widen;           // Limit on times we widen this sucker

  static const TypeInt *make(jint lo);
  // must always specify w
  static const TypeInt *make(jint lo, jint hi, int w);

  // Check for single integer
  int is_con() const { return _lo==_hi; }
  bool is_con(int i) const { return is_con() && _lo == i; }
  jint get_con() const { assert( is_con(), "" );  return _lo; }

  virtual bool        is_finite() const;  // Has a finite value

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.
  virtual const Type *widen( const Type *t, const Type* limit_type ) const;
  virtual const Type *narrow( const Type *t ) const;
  // Do not kill _widen bits.
  // Convenience common pre-built types.
  static const TypeInt *MINUS_1;
  static const TypeInt *ZERO;
  static const TypeInt *ONE;
  static const TypeInt *BOOL;
  static const TypeInt *CC;
  static const TypeInt *CC_LT;  // [-1]  == MINUS_1
  static const TypeInt *CC_GT;  // [1]   == ONE
  static const TypeInt *CC_EQ;  // [0]   == ZERO
  static const TypeInt *CC_LE;  // [-1,0]
  static const TypeInt *CC_GE;  // [0,1] == BOOL (!)
  static const TypeInt *BYTE;
  static const TypeInt *UBYTE;
  static const TypeInt *CHAR;
  static const TypeInt *SHORT;
  static const TypeInt *POS;
  static const TypeInt *POS1;
  static const TypeInt *INT;
  static const TypeInt *SYMINT; // symmetric range [-max_jint..max_jint]
  static const TypeInt *TYPE_DOMAIN; // alias for TypeInt::INT

  static const TypeInt *as_self(const Type *t) { return t->is_int(); }
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
#endif
};


//------------------------------TypeLong---------------------------------------
// Class of long integer ranges, the set of integers between a lower bound and
// an upper bound, inclusive.
class TypeLong : public Type {
  TypeLong( jlong lo, jlong hi, int w );
protected:
  // Do not kill _widen bits.
  virtual const Type *filter_helper(const Type *kills, bool include_speculative) const;
public:
  typedef jlong NativeType;
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous
public:
  const jlong _lo, _hi;         // Lower bound, upper bound
  const short _widen;           // Limit on times we widen this sucker

  static const TypeLong *make(jlong lo);
  // must always specify w
  static const TypeLong *make(jlong lo, jlong hi, int w);

  // Check for single integer
  int is_con() const { return _lo==_hi; }
  bool is_con(int i) const { return is_con() && _lo == i; }
  jlong get_con() const { assert( is_con(), "" ); return _lo; }

  // Check for positive 32-bit value.
  int is_positive_int() const { return _lo >= 0 && _hi <= (jlong)max_jint; }

  virtual bool        is_finite() const;  // Has a finite value


  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.
  virtual const Type *widen( const Type *t, const Type* limit_type ) const;
  virtual const Type *narrow( const Type *t ) const;
  // Convenience common pre-built types.
  static const TypeLong *MINUS_1;
  static const TypeLong *ZERO;
  static const TypeLong *ONE;
  static const TypeLong *POS;
  static const TypeLong *LONG;
  static const TypeLong *INT;    // 32-bit subrange [min_jint..max_jint]
  static const TypeLong *UINT;   // 32-bit unsigned [0..max_juint]
  static const TypeLong *TYPE_DOMAIN; // alias for TypeLong::LONG

  // static convenience methods.
  static const TypeLong *as_self(const Type *t) { return t->is_long(); }

#ifndef PRODUCT
  virtual void dump2( Dict &d, uint, outputStream *st  ) const;// Specialized per-Type dumping
#endif
};

//------------------------------TypeTuple--------------------------------------
// Class of Tuple Types, essentially type collections for function signatures
// and class layouts.  It happens to also be a fast cache for the HotSpot
// signature types.
class TypeTuple : public Type {
  TypeTuple( uint cnt, const Type **fields ) : Type(Tuple), _cnt(cnt), _fields(fields) { }

  const uint          _cnt;              // Count of fields
  const Type ** const _fields;           // Array of field types

public:
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous

  // Accessors:
  uint cnt() const { return _cnt; }
  const Type* field_at(uint i) const {
    assert(i < _cnt, "oob");
    return _fields[i];
  }
  void set_field_at(uint i, const Type* t) {
    assert(i < _cnt, "oob");
    _fields[i] = t;
  }

  static const TypeTuple *make( uint cnt, const Type **fields );
  static const TypeTuple *make_range(ciSignature *sig);
  static const TypeTuple *make_domain(ciInstanceKlass* recv, ciSignature *sig);

  // Subroutine call type with space allocated for argument types
  // Memory for Control, I_O, Memory, FramePtr, and ReturnAdr is allocated implicitly
  static const Type **fields( uint arg_cnt );

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.
  // Convenience common pre-built types.
  static const TypeTuple *IFBOTH;
  static const TypeTuple *IFFALSE;
  static const TypeTuple *IFTRUE;
  static const TypeTuple *IFNEITHER;
  static const TypeTuple *LOOPBODY;
  static const TypeTuple *MEMBAR;
  static const TypeTuple *STORECONDITIONAL;
  static const TypeTuple *START_I2C;
  static const TypeTuple *INT_PAIR;
  static const TypeTuple *LONG_PAIR;
  static const TypeTuple *INT_CC_PAIR;
  static const TypeTuple *LONG_CC_PAIR;
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint, outputStream *st  ) const; // Specialized per-Type dumping
#endif
};

//------------------------------TypeAry----------------------------------------
// Class of Array Types
class TypeAry : public Type {
  TypeAry(const Type* elem, const TypeInt* size, bool stable) : Type(Array),
      _elem(elem), _size(size), _stable(stable) {}
public:
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous

private:
  const Type *_elem;            // Element type of array
  const TypeInt *_size;         // Elements in array
  const bool _stable;           // Are elements @Stable?
  friend class TypeAryPtr;

public:
  static const TypeAry* make(const Type* elem, const TypeInt* size, bool stable = false);

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.
  bool ary_must_be_exact() const;  // true if arrays of such are never generic
  virtual const Type* remove_speculative() const;
  virtual const Type* cleanup_speculative() const;
#ifdef ASSERT
  // One type is interface, the other is oop
  virtual bool interface_vs_oop(const Type *t) const;
#endif
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint, outputStream *st  ) const; // Specialized per-Type dumping
#endif
};

//------------------------------TypeVect---------------------------------------
// Class of Vector Types
class TypeVect : public Type {
  const Type*   _elem;  // Vector's element type
  const uint  _length;  // Elements in vector (power of 2)

protected:
  TypeVect(TYPES t, const Type* elem, uint length) : Type(t),
    _elem(elem), _length(length) {}

public:
  const Type* element_type() const { return _elem; }
  BasicType element_basic_type() const { return _elem->array_element_basic_type(); }
  uint length() const { return _length; }
  uint length_in_bytes() const {
   return _length * type2aelembytes(element_basic_type());
  }

  virtual bool eq(const Type *t) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous

  static const TypeVect *make(const BasicType elem_bt, uint length) {
    // Use bottom primitive type.
    return make(get_const_basic_type(elem_bt), length);
  }
  // Used directly by Replicate nodes to construct singleton vector.
  static const TypeVect *make(const Type* elem, uint length);

  virtual const Type *xmeet( const Type *t) const;
  virtual const Type *xdual() const;     // Compute dual right now.

  static const TypeVect *VECTS;
  static const TypeVect *VECTD;
  static const TypeVect *VECTX;
  static const TypeVect *VECTY;
  static const TypeVect *VECTZ;

#ifndef PRODUCT
  virtual void dump2(Dict &d, uint, outputStream *st) const; // Specialized per-Type dumping
#endif
};

class TypeVectS : public TypeVect {
  friend class TypeVect;
  TypeVectS(const Type* elem, uint length) : TypeVect(VectorS, elem, length) {}
};

class TypeVectD : public TypeVect {
  friend class TypeVect;
  TypeVectD(const Type* elem, uint length) : TypeVect(VectorD, elem, length) {}
};

class TypeVectX : public TypeVect {
  friend class TypeVect;
  TypeVectX(const Type* elem, uint length) : TypeVect(VectorX, elem, length) {}
};

class TypeVectY : public TypeVect {
  friend class TypeVect;
  TypeVectY(const Type* elem, uint length) : TypeVect(VectorY, elem, length) {}
};

class TypeVectZ : public TypeVect {
  friend class TypeVect;
  TypeVectZ(const Type* elem, uint length) : TypeVect(VectorZ, elem, length) {}
};

//------------------------------TypePtr----------------------------------------
// Class of machine Pointer Types: raw data, instances or arrays.
// If the _base enum is AnyPtr, then this refers to all of the above.
// Otherwise the _base will indicate which subset of pointers is affected,
// and the class will be inherited from.
class TypePtr : public Type {
  friend class TypeNarrowPtr;
public:
  enum PTR { TopPTR, AnyNull, Constant, Null, NotNull, BotPTR, lastPTR };
protected:
  TypePtr(TYPES t, PTR ptr, int offset,
          const TypePtr* speculative = NULL,
          int inline_depth = InlineDepthBottom) :
    Type(t), _speculative(speculative), _inline_depth(inline_depth), _offset(offset),
    _ptr(ptr) {}
  static const PTR ptr_meet[lastPTR][lastPTR];
  static const PTR ptr_dual[lastPTR];
  static const char * const ptr_msg[lastPTR];

  enum {
    InlineDepthBottom = INT_MAX,
    InlineDepthTop = -InlineDepthBottom
  };

  // Extra type information profiling gave us. We propagate it the
  // same way the rest of the type info is propagated. If we want to
  // use it, then we have to emit a guard: this part of the type is
  // not something we know but something we speculate about the type.
  const TypePtr*   _speculative;
  // For speculative types, we record at what inlining depth the
  // profiling point that provided the data is. We want to favor
  // profile data coming from outer scopes which are likely better for
  // the current compilation.
  int _inline_depth;

  // utility methods to work on the speculative part of the type
  const TypePtr* dual_speculative() const;
  const TypePtr* xmeet_speculative(const TypePtr* other) const;
  bool eq_speculative(const TypePtr* other) const;
  int hash_speculative() const;
  const TypePtr* add_offset_speculative(intptr_t offset) const;
#ifndef PRODUCT
  void dump_speculative(outputStream *st) const;
#endif

  // utility methods to work on the inline depth of the type
  int dual_inline_depth() const;
  int meet_inline_depth(int depth) const;
#ifndef PRODUCT
  void dump_inline_depth(outputStream *st) const;
#endif

public:
  const int _offset;            // Offset into oop, with TOP & BOT
  const PTR _ptr;               // Pointer equivalence class

  const int offset() const { return _offset; }
  const PTR ptr()    const { return _ptr; }

  static const TypePtr *make(TYPES t, PTR ptr, int offset,
                             const TypePtr* speculative = NULL,
                             int inline_depth = InlineDepthBottom);

  // Return a 'ptr' version of this type
  virtual const Type *cast_to_ptr_type(PTR ptr) const;

  virtual intptr_t get_con() const;

  int xadd_offset( intptr_t offset ) const;
  virtual const TypePtr *add_offset( intptr_t offset ) const;
  virtual bool eq(const Type *t) const;
  virtual int  hash() const;             // Type specific hashing

  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous
  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xmeet_helper( const Type *t ) const;
  int meet_offset( int offset ) const;
  int dual_offset( ) const;
  virtual const Type *xdual() const;    // Compute dual right now.

  // meet, dual and join over pointer equivalence sets
  PTR meet_ptr( const PTR in_ptr ) const { return ptr_meet[in_ptr][ptr()]; }
  PTR dual_ptr()                   const { return ptr_dual[ptr()];      }

  // This is textually confusing unless one recalls that
  // join(t) == dual()->meet(t->dual())->dual().
  PTR join_ptr( const PTR in_ptr ) const {
    return ptr_dual[ ptr_meet[ ptr_dual[in_ptr] ] [ dual_ptr() ] ];
  }

  // Speculative type helper methods.
  virtual const TypePtr* speculative() const { return _speculative; }
  int inline_depth() const                   { return _inline_depth; }
  virtual ciKlass* speculative_type() const;
  virtual ciKlass* speculative_type_not_null() const;
  virtual bool speculative_maybe_null() const;
  virtual bool speculative_always_null() const;
  virtual const Type* remove_speculative() const;
  virtual const Type* cleanup_speculative() const;
  virtual bool would_improve_type(ciKlass* exact_kls, int inline_depth) const;
  virtual bool would_improve_ptr(ProfilePtrKind maybe_null) const;
  virtual const TypePtr* with_inline_depth(int depth) const;

  virtual bool maybe_null() const { return meet_ptr(Null) == ptr(); }

  // Tests for relation to centerline of type lattice:
  static bool above_centerline(PTR ptr) { return (ptr <= AnyNull); }
  static bool below_centerline(PTR ptr) { return (ptr >= NotNull); }
  // Convenience common pre-built types.
  static const TypePtr *NULL_PTR;
  static const TypePtr *NOTNULL;
  static const TypePtr *BOTTOM;
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st  ) const;
#endif
};

//------------------------------TypeRawPtr-------------------------------------
// Class of raw pointers, pointers to things other than Oops.  Examples
// include the stack pointer, top of heap, card-marking area, handles, etc.
class TypeRawPtr : public TypePtr {
protected:
  TypeRawPtr( PTR ptr, address bits ) : TypePtr(RawPtr,ptr,0), _bits(bits){}
public:
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;     // Type specific hashing

  const address _bits;          // Constant value, if applicable

  static const TypeRawPtr *make( PTR ptr );
  static const TypeRawPtr *make( address bits );

  // Return a 'ptr' version of this type
  virtual const Type *cast_to_ptr_type(PTR ptr) const;

  virtual intptr_t get_con() const;

  virtual const TypePtr *add_offset( intptr_t offset ) const;

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.
  // Convenience common pre-built types.
  static const TypeRawPtr *BOTTOM;
  static const TypeRawPtr *NOTNULL;
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st  ) const;
#endif
};

//------------------------------TypeOopPtr-------------------------------------
// Some kind of oop (Java pointer), either instance or array.
class TypeOopPtr : public TypePtr {
protected:
  TypeOopPtr(TYPES t, PTR ptr, ciKlass* k, bool xk, ciObject* o, int offset, int instance_id,
             const TypePtr* speculative, int inline_depth);
public:
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  enum {
   InstanceTop = -1,   // undefined instance
   InstanceBot = 0     // any possible instance
  };
protected:

  // Oop is NULL, unless this is a constant oop.
  ciObject*     _const_oop;   // Constant oop
  // If _klass is NULL, then so is _sig.  This is an unloaded klass.
  ciKlass*      _klass;       // Klass object
  // Does the type exclude subclasses of the klass?  (Inexact == polymorphic.)
  bool          _klass_is_exact;
  bool          _is_ptr_to_narrowoop;
  bool          _is_ptr_to_narrowklass;
  bool          _is_ptr_to_boxed_value;

  // If not InstanceTop or InstanceBot, indicates that this is
  // a particular instance of this type which is distinct.
  // This is the node index of the allocation node creating this instance.
  int           _instance_id;

  static const TypeOopPtr* make_from_klass_common(ciKlass* klass, bool klass_change, bool try_for_exact);

  int dual_instance_id() const;
  int meet_instance_id(int uid) const;

  // Do not allow interface-vs.-noninterface joins to collapse to top.
  virtual const Type *filter_helper(const Type *kills, bool include_speculative) const;

public:
  // Creates a type given a klass. Correctly handles multi-dimensional arrays
  // Respects UseUniqueSubclasses.
  // If the klass is final, the resulting type will be exact.
  static const TypeOopPtr* make_from_klass(ciKlass* klass) {
    return make_from_klass_common(klass, true, false);
  }
  // Same as before, but will produce an exact type, even if
  // the klass is not final, as long as it has exactly one implementation.
  static const TypeOopPtr* make_from_klass_unique(ciKlass* klass) {
    return make_from_klass_common(klass, true, true);
  }
  // Same as before, but does not respects UseUniqueSubclasses.
  // Use this only for creating array element types.
  static const TypeOopPtr* make_from_klass_raw(ciKlass* klass) {
    return make_from_klass_common(klass, false, false);
  }
  // Creates a singleton type given an object.
  // If the object cannot be rendered as a constant,
  // may return a non-singleton type.
  // If require_constant, produce a NULL if a singleton is not possible.
  static const TypeOopPtr* make_from_constant(ciObject* o,
                                              bool require_constant = false);

  // Make a generic (unclassed) pointer to an oop.
  static const TypeOopPtr* make(PTR ptr, int offset, int instance_id,
                                const TypePtr* speculative = NULL,
                                int inline_depth = InlineDepthBottom);

  ciObject* const_oop()    const { return _const_oop; }
  virtual ciKlass* klass() const { return _klass;     }
  bool klass_is_exact()    const { return _klass_is_exact; }

  // Returns true if this pointer points at memory which contains a
  // compressed oop references.
  bool is_ptr_to_narrowoop_nv() const { return _is_ptr_to_narrowoop; }
  bool is_ptr_to_narrowklass_nv() const { return _is_ptr_to_narrowklass; }
  bool is_ptr_to_boxed_value()   const { return _is_ptr_to_boxed_value; }
  bool is_known_instance()       const { return _instance_id > 0; }
  int  instance_id()             const { return _instance_id; }
  bool is_known_instance_field() const { return is_known_instance() && _offset >= 0; }

  virtual intptr_t get_con() const;

  virtual const Type *cast_to_ptr_type(PTR ptr) const;

  virtual const Type *cast_to_exactness(bool klass_is_exact) const;

  virtual const TypeOopPtr *cast_to_instance_id(int instance_id) const;

  // corresponding pointer to klass, for a given instance
  const TypeKlassPtr* as_klass_type() const;

  virtual const TypePtr *add_offset( intptr_t offset ) const;

  // Speculative type helper methods.
  virtual const Type* remove_speculative() const;
  virtual const Type* cleanup_speculative() const;
  virtual bool would_improve_type(ciKlass* exact_kls, int inline_depth) const;
  virtual const TypePtr* with_inline_depth(int depth) const;

  virtual const TypePtr* with_instance_id(int instance_id) const;

  virtual const Type *xdual() const;    // Compute dual right now.
  // the core of the computation of the meet for TypeOopPtr and for its subclasses
  virtual const Type *xmeet_helper(const Type *t) const;

  // Convenience common pre-built type.
  static const TypeOopPtr *BOTTOM;
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
#endif
};

//------------------------------TypeInstPtr------------------------------------
// Class of Java object pointers, pointing either to non-array Java instances
// or to a Klass* (including array klasses).
class TypeInstPtr : public TypeOopPtr {
  TypeInstPtr(PTR ptr, ciKlass* k, bool xk, ciObject* o, int offset, int instance_id,
              const TypePtr* speculative, int inline_depth);
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing

  ciSymbol*  _name;        // class name

 public:
  ciSymbol* name()         const { return _name; }

  bool  is_loaded() const { return _klass->is_loaded(); }

  // Make a pointer to a constant oop.
  static const TypeInstPtr *make(ciObject* o) {
    return make(TypePtr::Constant, o->klass(), true, o, 0, InstanceBot);
  }
  // Make a pointer to a constant oop with offset.
  static const TypeInstPtr *make(ciObject* o, int offset) {
    return make(TypePtr::Constant, o->klass(), true, o, offset, InstanceBot);
  }

  // Make a pointer to some value of type klass.
  static const TypeInstPtr *make(PTR ptr, ciKlass* klass) {
    return make(ptr, klass, false, NULL, 0, InstanceBot);
  }

  // Make a pointer to some non-polymorphic value of exactly type klass.
  static const TypeInstPtr *make_exact(PTR ptr, ciKlass* klass) {
    return make(ptr, klass, true, NULL, 0, InstanceBot);
  }

  // Make a pointer to some value of type klass with offset.
  static const TypeInstPtr *make(PTR ptr, ciKlass* klass, int offset) {
    return make(ptr, klass, false, NULL, offset, InstanceBot);
  }

  // Make a pointer to an oop.
  static const TypeInstPtr *make(PTR ptr, ciKlass* k, bool xk, ciObject* o, int offset,
                                 int instance_id = InstanceBot,
                                 const TypePtr* speculative = NULL,
                                 int inline_depth = InlineDepthBottom);

  /** Create constant type for a constant boxed value */
  const Type* get_const_boxed_value() const;

  // If this is a java.lang.Class constant, return the type for it or NULL.
  // Pass to Type::get_const_type to turn it to a type, which will usually
  // be a TypeInstPtr, but may also be a TypeInt::INT for int.class, etc.
  ciType* java_mirror_type() const;

  virtual const Type *cast_to_ptr_type(PTR ptr) const;

  virtual const Type *cast_to_exactness(bool klass_is_exact) const;

  virtual const TypeOopPtr *cast_to_instance_id(int instance_id) const;

  virtual const TypePtr *add_offset( intptr_t offset ) const;

  // Speculative type helper methods.
  virtual const Type* remove_speculative() const;
  virtual const TypePtr* with_inline_depth(int depth) const;
  virtual const TypePtr* with_instance_id(int instance_id) const;

  // the core of the computation of the meet of 2 types
  virtual const Type *xmeet_helper(const Type *t) const;
  virtual const TypeInstPtr *xmeet_unloaded( const TypeInstPtr *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.

  // Convenience common pre-built types.
  static const TypeInstPtr *NOTNULL;
  static const TypeInstPtr *BOTTOM;
  static const TypeInstPtr *MIRROR;
  static const TypeInstPtr *MARK;
  static const TypeInstPtr *KLASS;
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const; // Specialized per-Type dumping
#endif
};

//------------------------------TypeAryPtr-------------------------------------
// Class of Java array pointers
class TypeAryPtr : public TypeOopPtr {
  TypeAryPtr( PTR ptr, ciObject* o, const TypeAry *ary, ciKlass* k, bool xk,
              int offset, int instance_id, bool is_autobox_cache,
              const TypePtr* speculative, int inline_depth)
    : TypeOopPtr(AryPtr,ptr,k,xk,o,offset, instance_id, speculative, inline_depth),
    _ary(ary),
    _is_autobox_cache(is_autobox_cache)
 {
#ifdef ASSERT
    if (k != NULL) {
      // Verify that specified klass and TypeAryPtr::klass() follow the same rules.
      ciKlass* ck = compute_klass(true);
      if (k != ck) {
        this->dump(); tty->cr();
        tty->print(" k: ");
        k->print(); tty->cr();
        tty->print("ck: ");
        if (ck != NULL) ck->print();
        else tty->print("<NULL>");
        tty->cr();
        assert(false, "unexpected TypeAryPtr::_klass");
      }
    }
#endif
  }
  virtual bool eq( const Type *t ) const;
  virtual int hash() const;     // Type specific hashing
  const TypeAry *_ary;          // Array we point into
  const bool     _is_autobox_cache;

  ciKlass* compute_klass(DEBUG_ONLY(bool verify = false)) const;

public:
  // Accessors
  ciKlass* klass() const;
  const TypeAry* ary() const  { return _ary; }
  const Type*    elem() const { return _ary->_elem; }
  const TypeInt* size() const { return _ary->_size; }
  bool      is_stable() const { return _ary->_stable; }

  bool is_autobox_cache() const { return _is_autobox_cache; }

  static const TypeAryPtr *make(PTR ptr, const TypeAry *ary, ciKlass* k, bool xk, int offset,
                                int instance_id = InstanceBot,
                                const TypePtr* speculative = NULL,
                                int inline_depth = InlineDepthBottom);
  // Constant pointer to array
  static const TypeAryPtr *make(PTR ptr, ciObject* o, const TypeAry *ary, ciKlass* k, bool xk, int offset,
                                int instance_id = InstanceBot,
                                const TypePtr* speculative = NULL,
                                int inline_depth = InlineDepthBottom, bool is_autobox_cache = false);

  // Return a 'ptr' version of this type
  virtual const Type *cast_to_ptr_type(PTR ptr) const;

  virtual const Type *cast_to_exactness(bool klass_is_exact) const;

  virtual const TypeOopPtr *cast_to_instance_id(int instance_id) const;

  virtual const TypeAryPtr* cast_to_size(const TypeInt* size) const;
  virtual const TypeInt* narrow_size_type(const TypeInt* size) const;

  virtual bool empty(void) const;        // TRUE if type is vacuous
  virtual const TypePtr *add_offset( intptr_t offset ) const;

  // Speculative type helper methods.
  virtual const Type* remove_speculative() const;
  virtual const TypePtr* with_inline_depth(int depth) const;
  virtual const TypePtr* with_instance_id(int instance_id) const;

  // the core of the computation of the meet of 2 types
  virtual const Type *xmeet_helper(const Type *t) const;
  virtual const Type *xdual() const;    // Compute dual right now.

  const TypeAryPtr* cast_to_stable(bool stable, int stable_dimension = 1) const;
  int stable_dimension() const;

  const TypeAryPtr* cast_to_autobox_cache(bool cache) const;

  static jint max_array_length(BasicType etype) ;

  // Convenience common pre-built types.
  static const TypeAryPtr *RANGE;
  static const TypeAryPtr *OOPS;
  static const TypeAryPtr *NARROWOOPS;
  static const TypeAryPtr *BYTES;
  static const TypeAryPtr *SHORTS;
  static const TypeAryPtr *CHARS;
  static const TypeAryPtr *INTS;
  static const TypeAryPtr *LONGS;
  static const TypeAryPtr *FLOATS;
  static const TypeAryPtr *DOUBLES;
  // selects one of the above:
  static const TypeAryPtr *get_array_body_type(BasicType elem) {
    assert((uint)elem <= T_CONFLICT && _array_body_type[elem] != NULL, "bad elem type");
    return _array_body_type[elem];
  }
  static const TypeAryPtr *_array_body_type[T_CONFLICT+1];
  // sharpen the type of an int which is used as an array size
#ifdef ASSERT
  // One type is interface, the other is oop
  virtual bool interface_vs_oop(const Type *t) const;
#endif
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const; // Specialized per-Type dumping
#endif
};

//------------------------------TypeMetadataPtr-------------------------------------
// Some kind of metadata, either Method*, MethodData* or CPCacheOop
class TypeMetadataPtr : public TypePtr {
protected:
  TypeMetadataPtr(PTR ptr, ciMetadata* metadata, int offset);
  // Do not allow interface-vs.-noninterface joins to collapse to top.
  virtual const Type *filter_helper(const Type *kills, bool include_speculative) const;
public:
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton

private:
  ciMetadata*   _metadata;

public:
  static const TypeMetadataPtr* make(PTR ptr, ciMetadata* m, int offset);

  static const TypeMetadataPtr* make(ciMethod* m);
  static const TypeMetadataPtr* make(ciMethodData* m);

  ciMetadata* metadata() const { return _metadata; }

  virtual const Type *cast_to_ptr_type(PTR ptr) const;

  virtual const TypePtr *add_offset( intptr_t offset ) const;

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.

  virtual intptr_t get_con() const;

  // Convenience common pre-built types.
  static const TypeMetadataPtr *BOTTOM;

#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
#endif
};

//------------------------------TypeKlassPtr-----------------------------------
// Class of Java Klass pointers
class TypeKlassPtr : public TypePtr {
  TypeKlassPtr( PTR ptr, ciKlass* klass, int offset );

protected:
  virtual const Type *filter_helper(const Type *kills, bool include_speculative) const;
 public:
  virtual bool eq( const Type *t ) const;
  virtual int hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
 private:

  static const TypeKlassPtr* make_from_klass_common(ciKlass* klass, bool klass_change, bool try_for_exact);

  ciKlass* _klass;

  // Does the type exclude subclasses of the klass?  (Inexact == polymorphic.)
  bool          _klass_is_exact;

public:
  ciSymbol* name()  const { return klass()->name(); }

  ciKlass* klass() const { return  _klass; }
  bool klass_is_exact()    const { return _klass_is_exact; }

  bool  is_loaded() const { return klass()->is_loaded(); }

  // Creates a type given a klass. Correctly handles multi-dimensional arrays
  // Respects UseUniqueSubclasses.
  // If the klass is final, the resulting type will be exact.
  static const TypeKlassPtr* make_from_klass(ciKlass* klass) {
    return make_from_klass_common(klass, true, false);
  }
  // Same as before, but will produce an exact type, even if
  // the klass is not final, as long as it has exactly one implementation.
  static const TypeKlassPtr* make_from_klass_unique(ciKlass* klass) {
    return make_from_klass_common(klass, true, true);
  }
  // Same as before, but does not respects UseUniqueSubclasses.
  // Use this only for creating array element types.
  static const TypeKlassPtr* make_from_klass_raw(ciKlass* klass) {
    return make_from_klass_common(klass, false, false);
  }

  // Make a generic (unclassed) pointer to metadata.
  static const TypeKlassPtr* make(PTR ptr, int offset);

  // ptr to klass 'k'
  static const TypeKlassPtr *make( ciKlass* k ) { return make( TypePtr::Constant, k, 0); }
  // ptr to klass 'k' with offset
  static const TypeKlassPtr *make( ciKlass* k, int offset ) { return make( TypePtr::Constant, k, offset); }
  // ptr to klass 'k' or sub-klass
  static const TypeKlassPtr *make( PTR ptr, ciKlass* k, int offset);

  virtual const Type *cast_to_ptr_type(PTR ptr) const;

  virtual const Type *cast_to_exactness(bool klass_is_exact) const;

  // corresponding pointer to instance, for a given class
  const TypeOopPtr* as_instance_type() const;

  virtual const TypePtr *add_offset( intptr_t offset ) const;
  virtual const Type    *xmeet( const Type *t ) const;
  virtual const Type    *xdual() const;      // Compute dual right now.

  virtual intptr_t get_con() const;

  // Convenience common pre-built types.
  static const TypeKlassPtr* OBJECT; // Not-null object klass or below
  static const TypeKlassPtr* OBJECT_OR_NULL; // Maybe-null version of same
#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const; // Specialized per-Type dumping
#endif
};

class TypeNarrowPtr : public Type {
protected:
  const TypePtr* _ptrtype; // Could be TypePtr::NULL_PTR

  TypeNarrowPtr(TYPES t, const TypePtr* ptrtype): Type(t),
                                                  _ptrtype(ptrtype) {
    assert(ptrtype->offset() == 0 ||
           ptrtype->offset() == OffsetBot ||
           ptrtype->offset() == OffsetTop, "no real offsets");
  }

  virtual const TypeNarrowPtr *isa_same_narrowptr(const Type *t) const = 0;
  virtual const TypeNarrowPtr *is_same_narrowptr(const Type *t) const = 0;
  virtual const TypeNarrowPtr *make_same_narrowptr(const TypePtr *t) const = 0;
  virtual const TypeNarrowPtr *make_hash_same_narrowptr(const TypePtr *t) const = 0;
  // Do not allow interface-vs.-noninterface joins to collapse to top.
  virtual const Type *filter_helper(const Type *kills, bool include_speculative) const;
public:
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.

  virtual intptr_t get_con() const;

  virtual bool empty(void) const;        // TRUE if type is vacuous

  // returns the equivalent ptr type for this compressed pointer
  const TypePtr *get_ptrtype() const {
    return _ptrtype;
  }

  bool is_known_instance() const {
    return _ptrtype->is_known_instance();
  }

#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
#endif
};

//------------------------------TypeNarrowOop----------------------------------
// A compressed reference to some kind of Oop.  This type wraps around
// a preexisting TypeOopPtr and forwards most of it's operations to
// the underlying type.  It's only real purpose is to track the
// oopness of the compressed oop value when we expose the conversion
// between the normal and the compressed form.
class TypeNarrowOop : public TypeNarrowPtr {
protected:
  TypeNarrowOop( const TypePtr* ptrtype): TypeNarrowPtr(NarrowOop, ptrtype) {
  }

  virtual const TypeNarrowPtr *isa_same_narrowptr(const Type *t) const {
    return t->isa_narrowoop();
  }

  virtual const TypeNarrowPtr *is_same_narrowptr(const Type *t) const {
    return t->is_narrowoop();
  }

  virtual const TypeNarrowPtr *make_same_narrowptr(const TypePtr *t) const {
    return new TypeNarrowOop(t);
  }

  virtual const TypeNarrowPtr *make_hash_same_narrowptr(const TypePtr *t) const {
    return (const TypeNarrowPtr*)((new TypeNarrowOop(t))->hashcons());
  }

public:

  static const TypeNarrowOop *make( const TypePtr* type);

  static const TypeNarrowOop* make_from_constant(ciObject* con, bool require_constant = false) {
    return make(TypeOopPtr::make_from_constant(con, require_constant));
  }

  static const TypeNarrowOop *BOTTOM;
  static const TypeNarrowOop *NULL_PTR;

  virtual const Type* remove_speculative() const;
  virtual const Type* cleanup_speculative() const;

#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
#endif
};

//------------------------------TypeNarrowKlass----------------------------------
// A compressed reference to klass pointer.  This type wraps around a
// preexisting TypeKlassPtr and forwards most of it's operations to
// the underlying type.
class TypeNarrowKlass : public TypeNarrowPtr {
protected:
  TypeNarrowKlass( const TypePtr* ptrtype): TypeNarrowPtr(NarrowKlass, ptrtype) {
  }

  virtual const TypeNarrowPtr *isa_same_narrowptr(const Type *t) const {
    return t->isa_narrowklass();
  }

  virtual const TypeNarrowPtr *is_same_narrowptr(const Type *t) const {
    return t->is_narrowklass();
  }

  virtual const TypeNarrowPtr *make_same_narrowptr(const TypePtr *t) const {
    return new TypeNarrowKlass(t);
  }

  virtual const TypeNarrowPtr *make_hash_same_narrowptr(const TypePtr *t) const {
    return (const TypeNarrowPtr*)((new TypeNarrowKlass(t))->hashcons());
  }

public:
  static const TypeNarrowKlass *make( const TypePtr* type);

  // static const TypeNarrowKlass *BOTTOM;
  static const TypeNarrowKlass *NULL_PTR;

#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
#endif
};

//------------------------------TypeFunc---------------------------------------
// Class of Array Types
class TypeFunc : public Type {
  TypeFunc( const TypeTuple *domain, const TypeTuple *range ) : Type(Function),  _domain(domain), _range(range) {}
  virtual bool eq( const Type *t ) const;
  virtual int  hash() const;             // Type specific hashing
  virtual bool singleton(void) const;    // TRUE if type is a singleton
  virtual bool empty(void) const;        // TRUE if type is vacuous

  const TypeTuple* const _domain;     // Domain of inputs
  const TypeTuple* const _range;      // Range of results

public:
  // Constants are shared among ADLC and VM
  enum { Control    = AdlcVMDeps::Control,
         I_O        = AdlcVMDeps::I_O,
         Memory     = AdlcVMDeps::Memory,
         FramePtr   = AdlcVMDeps::FramePtr,
         ReturnAdr  = AdlcVMDeps::ReturnAdr,
         Parms      = AdlcVMDeps::Parms
  };


  // Accessors:
  const TypeTuple* domain() const { return _domain; }
  const TypeTuple* range()  const { return _range; }

  static const TypeFunc *make(ciMethod* method);
  static const TypeFunc *make(ciSignature signature, const Type* extra);
  static const TypeFunc *make(const TypeTuple* domain, const TypeTuple* range);

  virtual const Type *xmeet( const Type *t ) const;
  virtual const Type *xdual() const;    // Compute dual right now.

  BasicType return_type() const;

#ifndef PRODUCT
  virtual void dump2( Dict &d, uint depth, outputStream *st ) const; // Specialized per-Type dumping
#endif
  // Convenience common pre-built types.
};

//------------------------------accessors--------------------------------------
inline bool Type::is_ptr_to_narrowoop() const {
#ifdef _LP64
  return (isa_oopptr() != NULL && is_oopptr()->is_ptr_to_narrowoop_nv());
#else
  return false;
#endif
}

inline bool Type::is_ptr_to_narrowklass() const {
#ifdef _LP64
  return (isa_oopptr() != NULL && is_oopptr()->is_ptr_to_narrowklass_nv());
#else
  return false;
#endif
}

inline float Type::getf() const {
  assert( _base == FloatCon, "Not a FloatCon" );
  return ((TypeF*)this)->_f;
}

inline double Type::getd() const {
  assert( _base == DoubleCon, "Not a DoubleCon" );
  return ((TypeD*)this)->_d;
}

inline const TypeInt *Type::is_int() const {
  assert( _base == Int, "Not an Int" );
  return (TypeInt*)this;
}

inline const TypeInt *Type::isa_int() const {
  return ( _base == Int ? (TypeInt*)this : NULL);
}

inline const TypeLong *Type::is_long() const {
  assert( _base == Long, "Not a Long" );
  return (TypeLong*)this;
}

inline const TypeLong *Type::isa_long() const {
  return ( _base == Long ? (TypeLong*)this : NULL);
}

inline const TypeF *Type::isa_float() const {
  return ((_base == FloatTop ||
           _base == FloatCon ||
           _base == FloatBot) ? (TypeF*)this : NULL);
}

inline const TypeF *Type::is_float_constant() const {
  assert( _base == FloatCon, "Not a Float" );
  return (TypeF*)this;
}

inline const TypeF *Type::isa_float_constant() const {
  return ( _base == FloatCon ? (TypeF*)this : NULL);
}

inline const TypeD *Type::isa_double() const {
  return ((_base == DoubleTop ||
           _base == DoubleCon ||
           _base == DoubleBot) ? (TypeD*)this : NULL);
}

inline const TypeD *Type::is_double_constant() const {
  assert( _base == DoubleCon, "Not a Double" );
  return (TypeD*)this;
}

inline const TypeD *Type::isa_double_constant() const {
  return ( _base == DoubleCon ? (TypeD*)this : NULL);
}

inline const TypeTuple *Type::is_tuple() const {
  assert( _base == Tuple, "Not a Tuple" );
  return (TypeTuple*)this;
}

inline const TypeAry *Type::is_ary() const {
  assert( _base == Array , "Not an Array" );
  return (TypeAry*)this;
}

inline const TypeAry *Type::isa_ary() const {
  return ((_base == Array) ? (TypeAry*)this : NULL);
}

inline const TypeVect *Type::is_vect() const {
  assert( _base >= VectorS && _base <= VectorZ, "Not a Vector" );
  return (TypeVect*)this;
}

inline const TypeVect *Type::isa_vect() const {
  return (_base >= VectorS && _base <= VectorZ) ? (TypeVect*)this : NULL;
}

inline const TypePtr *Type::is_ptr() const {
  // AnyPtr is the first Ptr and KlassPtr the last, with no non-ptrs between.
  assert(_base >= AnyPtr && _base <= KlassPtr, "Not a pointer");
  return (TypePtr*)this;
}

inline const TypePtr *Type::isa_ptr() const {
  // AnyPtr is the first Ptr and KlassPtr the last, with no non-ptrs between.
  return (_base >= AnyPtr && _base <= KlassPtr) ? (TypePtr*)this : NULL;
}

inline const TypeOopPtr *Type::is_oopptr() const {
  // OopPtr is the first and KlassPtr the last, with no non-oops between.
  assert(_base >= OopPtr && _base <= AryPtr, "Not a Java pointer" ) ;
  return (TypeOopPtr*)this;
}

inline const TypeOopPtr *Type::isa_oopptr() const {
  // OopPtr is the first and KlassPtr the last, with no non-oops between.
  return (_base >= OopPtr && _base <= AryPtr) ? (TypeOopPtr*)this : NULL;
}

inline const TypeRawPtr *Type::isa_rawptr() const {
  return (_base == RawPtr) ? (TypeRawPtr*)this : NULL;
}

inline const TypeRawPtr *Type::is_rawptr() const {
  assert( _base == RawPtr, "Not a raw pointer" );
  return (TypeRawPtr*)this;
}

inline const TypeInstPtr *Type::isa_instptr() const {
  return (_base == InstPtr) ? (TypeInstPtr*)this : NULL;
}

inline const TypeInstPtr *Type::is_instptr() const {
  assert( _base == InstPtr, "Not an object pointer" );
  return (TypeInstPtr*)this;
}

inline const TypeAryPtr *Type::isa_aryptr() const {
  return (_base == AryPtr) ? (TypeAryPtr*)this : NULL;
}

inline const TypeAryPtr *Type::is_aryptr() const {
  assert( _base == AryPtr, "Not an array pointer" );
  return (TypeAryPtr*)this;
}

inline const TypeNarrowOop *Type::is_narrowoop() const {
  // OopPtr is the first and KlassPtr the last, with no non-oops between.
  assert(_base == NarrowOop, "Not a narrow oop" ) ;
  return (TypeNarrowOop*)this;
}

inline const TypeNarrowOop *Type::isa_narrowoop() const {
  // OopPtr is the first and KlassPtr the last, with no non-oops between.
  return (_base == NarrowOop) ? (TypeNarrowOop*)this : NULL;
}

inline const TypeNarrowKlass *Type::is_narrowklass() const {
  assert(_base == NarrowKlass, "Not a narrow oop" ) ;
  return (TypeNarrowKlass*)this;
}

inline const TypeNarrowKlass *Type::isa_narrowklass() const {
  return (_base == NarrowKlass) ? (TypeNarrowKlass*)this : NULL;
}

inline const TypeMetadataPtr *Type::is_metadataptr() const {
  // MetadataPtr is the first and CPCachePtr the last
  assert(_base == MetadataPtr, "Not a metadata pointer" ) ;
  return (TypeMetadataPtr*)this;
}

inline const TypeMetadataPtr *Type::isa_metadataptr() const {
  return (_base == MetadataPtr) ? (TypeMetadataPtr*)this : NULL;
}

inline const TypeKlassPtr *Type::isa_klassptr() const {
  return (_base == KlassPtr) ? (TypeKlassPtr*)this : NULL;
}

inline const TypeKlassPtr *Type::is_klassptr() const {
  assert( _base == KlassPtr, "Not a klass pointer" );
  return (TypeKlassPtr*)this;
}

inline const TypePtr* Type::make_ptr() const {
  return (_base == NarrowOop) ? is_narrowoop()->get_ptrtype() :
                              ((_base == NarrowKlass) ? is_narrowklass()->get_ptrtype() :
                                                       isa_ptr());
}

inline const TypeOopPtr* Type::make_oopptr() const {
  return (_base == NarrowOop) ? is_narrowoop()->get_ptrtype()->isa_oopptr() : isa_oopptr();
}

inline const TypeNarrowOop* Type::make_narrowoop() const {
  return (_base == NarrowOop) ? is_narrowoop() :
                                (isa_ptr() ? TypeNarrowOop::make(is_ptr()) : NULL);
}

inline const TypeNarrowKlass* Type::make_narrowklass() const {
  return (_base == NarrowKlass) ? is_narrowklass() :
                                  (isa_ptr() ? TypeNarrowKlass::make(is_ptr()) : NULL);
}

inline bool Type::is_floatingpoint() const {
  if( (_base == FloatCon)  || (_base == FloatBot) ||
      (_base == DoubleCon) || (_base == DoubleBot) )
    return true;
  return false;
}

inline bool Type::is_ptr_to_boxing_obj() const {
  const TypeInstPtr* tp = isa_instptr();
  return (tp != NULL) && (tp->offset() == 0) &&
         tp->klass()->is_instance_klass()  &&
         tp->klass()->as_instance_klass()->is_box_klass();
}


// ===============================================================
// Things that need to be 64-bits in the 64-bit build but
// 32-bits in the 32-bit build.  Done this way to get full
// optimization AND strong typing.
#ifdef _LP64

// For type queries and asserts
#define is_intptr_t  is_long
#define isa_intptr_t isa_long
#define find_intptr_t_type find_long_type
#define find_intptr_t_con  find_long_con
#define TypeX        TypeLong
#define Type_X       Type::Long
#define TypeX_X      TypeLong::LONG
#define TypeX_ZERO   TypeLong::ZERO
// For 'ideal_reg' machine registers
#define Op_RegX      Op_RegL
// For phase->intcon variants
#define MakeConX     longcon
#define ConXNode     ConLNode
// For array index arithmetic
#define MulXNode     MulLNode
#define AndXNode     AndLNode
#define OrXNode      OrLNode
#define CmpXNode     CmpLNode
#define SubXNode     SubLNode
#define LShiftXNode  LShiftLNode
// For object size computation:
#define AddXNode     AddLNode
#define RShiftXNode  RShiftLNode
// For card marks and hashcodes
#define URShiftXNode URShiftLNode
// UseOptoBiasInlining
#define XorXNode     XorLNode
#define StoreXConditionalNode StoreLConditionalNode
#define LoadXNode    LoadLNode
#define StoreXNode   StoreLNode
// Opcodes
#define Op_LShiftX   Op_LShiftL
#define Op_AndX      Op_AndL
#define Op_AddX      Op_AddL
#define Op_SubX      Op_SubL
#define Op_XorX      Op_XorL
#define Op_URShiftX  Op_URShiftL
#define Op_LoadX     Op_LoadL
// conversions
#define ConvI2X(x)   ConvI2L(x)
#define ConvL2X(x)   (x)
#define ConvX2I(x)   ConvL2I(x)
#define ConvX2L(x)   (x)
#define ConvX2UL(x)  (x)

#else

// For type queries and asserts
#define is_intptr_t  is_int
#define isa_intptr_t isa_int
#define find_intptr_t_type find_int_type
#define find_intptr_t_con  find_int_con
#define TypeX        TypeInt
#define Type_X       Type::Int
#define TypeX_X      TypeInt::INT
#define TypeX_ZERO   TypeInt::ZERO
// For 'ideal_reg' machine registers
#define Op_RegX      Op_RegI
// For phase->intcon variants
#define MakeConX     intcon
#define ConXNode     ConINode
// For array index arithmetic
#define MulXNode     MulINode
#define AndXNode     AndINode
#define OrXNode      OrINode
#define CmpXNode     CmpINode
#define SubXNode     SubINode
#define LShiftXNode  LShiftINode
// For object size computation:
#define AddXNode     AddINode
#define RShiftXNode  RShiftINode
// For card marks and hashcodes
#define URShiftXNode URShiftINode
// UseOptoBiasInlining
#define XorXNode     XorINode
#define StoreXConditionalNode StoreIConditionalNode
#define LoadXNode    LoadINode
#define StoreXNode   StoreINode
// Opcodes
#define Op_LShiftX   Op_LShiftI
#define Op_AndX      Op_AndI
#define Op_AddX      Op_AddI
#define Op_SubX      Op_SubI
#define Op_XorX      Op_XorI
#define Op_URShiftX  Op_URShiftI
#define Op_LoadX     Op_LoadI
// conversions
#define ConvI2X(x)   (x)
#define ConvL2X(x)   ConvL2I(x)
#define ConvX2I(x)   (x)
#define ConvX2L(x)   ConvI2L(x)
#define ConvX2UL(x)  ConvI2UL(x)

#endif

#endif // SHARE_OPTO_TYPE_HPP