jdk8-mips64-public/hotspot: src/share/vm/opto/type.cpp@884ed7a10f09 (annotated)

src/share/vm/opto/type.cpp@884ed7a10f09 (annotated)

src/share/vm/opto/type.cpp

Mon, 16 Sep 2013 09:41:03 +0200

author: tschatzl
date: Mon, 16 Sep 2013 09:41:03 +0200
changeset 5710: 884ed7a10f09
parent 5694: 7944aba7ba41
parent 5658: edb5ab0f3fe5
child 5791: c9ccd7b85f20
permissions: -rw-r--r--

Merge

 /*
  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * 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).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "ci/ciMethodData.hpp"
 #include "ci/ciTypeFlow.hpp"
 #include "classfile/symbolTable.hpp"
 #include "classfile/systemDictionary.hpp"
 #include "compiler/compileLog.hpp"
 #include "libadt/dict.hpp"
 #include "memory/gcLocker.hpp"
 #include "memory/oopFactory.hpp"
 #include "memory/resourceArea.hpp"
 #include "oops/instanceKlass.hpp"
 #include "oops/instanceMirrorKlass.hpp"
 #include "oops/objArrayKlass.hpp"
 #include "oops/typeArrayKlass.hpp"
 #include "opto/matcher.hpp"
 #include "opto/node.hpp"
 #include "opto/opcodes.hpp"
 #include "opto/type.hpp"
 // Portions of code courtesy of Clifford Click
 // Optimization - Graph Style
 // Dictionary of types shared among compilations.
 Dict* Type::_shared_type_dict = NULL;
 // Array which maps compiler types to Basic Types
 Type::TypeInfo Type::_type_info[Type::lastype] = {
   { Bad,             T_ILLEGAL,    "bad",           false, Node::NotAMachineReg, relocInfo::none          },  // Bad
   { Control,         T_ILLEGAL,    "control",       false, 0,                    relocInfo::none          },  // Control
   { Bottom,          T_VOID,       "top",           false, 0,                    relocInfo::none          },  // Top
   { Bad,             T_INT,        "int:",          false, Op_RegI,              relocInfo::none          },  // Int
   { Bad,             T_LONG,       "long:",         false, Op_RegL,              relocInfo::none          },  // Long
   { Half,            T_VOID,       "half",          false, 0,                    relocInfo::none          },  // Half
   { Bad,             T_NARROWOOP,  "narrowoop:",    false, Op_RegN,              relocInfo::none          },  // NarrowOop
   { Bad,             T_NARROWKLASS,"narrowklass:",  false, Op_RegN,              relocInfo::none          },  // NarrowKlass
   { Bad,             T_ILLEGAL,    "tuple:",        false, Node::NotAMachineReg, relocInfo::none          },  // Tuple
   { Bad,             T_ARRAY,      "array:",        false, Node::NotAMachineReg, relocInfo::none          },  // Array
 #ifndef SPARC
   { Bad,             T_ILLEGAL,    "vectors:",      false, Op_VecS,              relocInfo::none          },  // VectorS
   { Bad,             T_ILLEGAL,    "vectord:",      false, Op_VecD,              relocInfo::none          },  // VectorD
   { Bad,             T_ILLEGAL,    "vectorx:",      false, Op_VecX,              relocInfo::none          },  // VectorX
   { Bad,             T_ILLEGAL,    "vectory:",      false, Op_VecY,              relocInfo::none          },  // VectorY
 #else
   { Bad,             T_ILLEGAL,    "vectors:",      false, 0,                    relocInfo::none          },  // VectorS
   { Bad,             T_ILLEGAL,    "vectord:",      false, Op_RegD,              relocInfo::none          },  // VectorD
   { Bad,             T_ILLEGAL,    "vectorx:",      false, 0,                    relocInfo::none          },  // VectorX
   { Bad,             T_ILLEGAL,    "vectory:",      false, 0,                    relocInfo::none          },  // VectorY
 #endif // IA32 || AMD64
   { Bad,             T_ADDRESS,    "anyptr:",       false, Op_RegP,              relocInfo::none          },  // AnyPtr
   { Bad,             T_ADDRESS,    "rawptr:",       false, Op_RegP,              relocInfo::none          },  // RawPtr
   { Bad,             T_OBJECT,     "oop:",          true,  Op_RegP,              relocInfo::oop_type      },  // OopPtr
   { Bad,             T_OBJECT,     "inst:",         true,  Op_RegP,              relocInfo::oop_type      },  // InstPtr
   { Bad,             T_OBJECT,     "ary:",          true,  Op_RegP,              relocInfo::oop_type      },  // AryPtr
   { Bad,             T_METADATA,   "metadata:",     false, Op_RegP,              relocInfo::metadata_type },  // MetadataPtr
   { Bad,             T_METADATA,   "klass:",        false, Op_RegP,              relocInfo::metadata_type },  // KlassPtr
   { Bad,             T_OBJECT,     "func",          false, 0,                    relocInfo::none          },  // Function
   { Abio,            T_ILLEGAL,    "abIO",          false, 0,                    relocInfo::none          },  // Abio
   { Return_Address,  T_ADDRESS,    "return_address",false, Op_RegP,              relocInfo::none          },  // Return_Address
   { Memory,          T_ILLEGAL,    "memory",        false, 0,                    relocInfo::none          },  // Memory
   { FloatBot,        T_FLOAT,      "float_top",     false, Op_RegF,              relocInfo::none          },  // FloatTop
   { FloatCon,        T_FLOAT,      "ftcon:",        false, Op_RegF,              relocInfo::none          },  // FloatCon
   { FloatTop,        T_FLOAT,      "float",         false, Op_RegF,              relocInfo::none          },  // FloatBot
   { DoubleBot,       T_DOUBLE,     "double_top",    false, Op_RegD,              relocInfo::none          },  // DoubleTop
   { DoubleCon,       T_DOUBLE,     "dblcon:",       false, Op_RegD,              relocInfo::none          },  // DoubleCon
   { DoubleTop,       T_DOUBLE,     "double",        false, Op_RegD,              relocInfo::none          },  // DoubleBot
   { Top,             T_ILLEGAL,    "bottom",        false, 0,                    relocInfo::none          }   // Bottom
 };
 // Map ideal registers (machine types) to ideal types
 const Type *Type::mreg2type[_last_machine_leaf];
 // Map basic types to canonical Type* pointers.
 const Type* Type::     _const_basic_type[T_CONFLICT+1];
 // Map basic types to constant-zero Types.
 const Type* Type::            _zero_type[T_CONFLICT+1];
 // Map basic types to array-body alias types.
 const TypeAryPtr* TypeAryPtr::_array_body_type[T_CONFLICT+1];
 //=============================================================================
 // Convenience common pre-built types.
 const Type *Type::ABIO;         // State-of-machine only
 const Type *Type::BOTTOM;       // All values
 const Type *Type::CONTROL;      // Control only
 const Type *Type::DOUBLE;       // All doubles
 const Type *Type::FLOAT;        // All floats
 const Type *Type::HALF;         // Placeholder half of doublewide type
 const Type *Type::MEMORY;       // Abstract store only
 const Type *Type::RETURN_ADDRESS;
 const Type *Type::TOP;          // No values in set
 //------------------------------get_const_type---------------------------
 const Type* Type::get_const_type(ciType* type) {
   if (type == NULL) {
     return NULL;
   } else if (type->is_primitive_type()) {
     return get_const_basic_type(type->basic_type());
   } else {
     return TypeOopPtr::make_from_klass(type->as_klass());
   }
 }
 //---------------------------array_element_basic_type---------------------------------
 // Mapping to the array element's basic type.
 BasicType Type::array_element_basic_type() const {
   BasicType bt = basic_type();
   if (bt == T_INT) {
     if (this == TypeInt::INT)   return T_INT;
     if (this == TypeInt::CHAR)  return T_CHAR;
     if (this == TypeInt::BYTE)  return T_BYTE;
     if (this == TypeInt::BOOL)  return T_BOOLEAN;
     if (this == TypeInt::SHORT) return T_SHORT;
     return T_VOID;
   }
   return bt;
 }
 //---------------------------get_typeflow_type---------------------------------
 // Import a type produced by ciTypeFlow.
 const Type* Type::get_typeflow_type(ciType* type) {
   switch (type->basic_type()) {
   case ciTypeFlow::StateVector::T_BOTTOM:
     assert(type == ciTypeFlow::StateVector::bottom_type(), "");
     return Type::BOTTOM;
   case ciTypeFlow::StateVector::T_TOP:
     assert(type == ciTypeFlow::StateVector::top_type(), "");
     return Type::TOP;
   case ciTypeFlow::StateVector::T_NULL:
     assert(type == ciTypeFlow::StateVector::null_type(), "");
     return TypePtr::NULL_PTR;
   case ciTypeFlow::StateVector::T_LONG2:
     // The ciTypeFlow pass pushes a long, then the half.
     // We do the same.
     assert(type == ciTypeFlow::StateVector::long2_type(), "");
     return TypeInt::TOP;
   case ciTypeFlow::StateVector::T_DOUBLE2:
     // The ciTypeFlow pass pushes double, then the half.
     // Our convention is the same.
     assert(type == ciTypeFlow::StateVector::double2_type(), "");
     return Type::TOP;
   case T_ADDRESS:
     assert(type->is_return_address(), "");
     return TypeRawPtr::make((address)(intptr_t)type->as_return_address()->bci());
   default:
     // make sure we did not mix up the cases:
     assert(type != ciTypeFlow::StateVector::bottom_type(), "");
     assert(type != ciTypeFlow::StateVector::top_type(), "");
     assert(type != ciTypeFlow::StateVector::null_type(), "");
     assert(type != ciTypeFlow::StateVector::long2_type(), "");
     assert(type != ciTypeFlow::StateVector::double2_type(), "");
     assert(!type->is_return_address(), "");
     return Type::get_const_type(type);
   }
 }
 //-----------------------make_from_constant------------------------------------
 const Type* Type::make_from_constant(ciConstant constant,
                                      bool require_constant, bool is_autobox_cache) {
   switch (constant.basic_type()) {
   case T_BOOLEAN:  return TypeInt::make(constant.as_boolean());
   case T_CHAR:     return TypeInt::make(constant.as_char());
   case T_BYTE:     return TypeInt::make(constant.as_byte());
   case T_SHORT:    return TypeInt::make(constant.as_short());
   case T_INT:      return TypeInt::make(constant.as_int());
   case T_LONG:     return TypeLong::make(constant.as_long());
   case T_FLOAT:    return TypeF::make(constant.as_float());
   case T_DOUBLE:   return TypeD::make(constant.as_double());
   case T_ARRAY:
   case T_OBJECT:
     {
       // cases:
       //   can_be_constant    = (oop not scavengable || ScavengeRootsInCode != 0)
       //   should_be_constant = (oop not scavengable || ScavengeRootsInCode >= 2)
       // An oop is not scavengable if it is in the perm gen.
       ciObject* oop_constant = constant.as_object();
       if (oop_constant->is_null_object()) {
         return Type::get_zero_type(T_OBJECT);
       } else if (require_constant || oop_constant->should_be_constant()) {
         return TypeOopPtr::make_from_constant(oop_constant, require_constant, is_autobox_cache);
       }
     }
   }
   // Fall through to failure
   return NULL;
 }
 //------------------------------make-------------------------------------------
 // Create a simple Type, with default empty symbol sets.  Then hashcons it
 // and look for an existing copy in the type dictionary.
 const Type *Type::make( enum TYPES t ) {
   return (new Type(t))->hashcons();
 }
 //------------------------------cmp--------------------------------------------
 int Type::cmp( const Type *const t1, const Type *const t2 ) {
   if( t1->_base != t2->_base )
     return 1;                   // Missed badly
   assert(t1 != t2 || t1->eq(t2), "eq must be reflexive");
   return !t1->eq(t2);           // Return ZERO if equal
 }
 //------------------------------hash-------------------------------------------
 int Type::uhash( const Type *const t ) {
   return t->hash();
 }
 #define SMALLINT ((juint)3)  // a value too insignificant to consider widening
 //--------------------------Initialize_shared----------------------------------
 void Type::Initialize_shared(Compile* current) {
   // This method does not need to be locked because the first system
   // compilations (stub compilations) occur serially.  If they are
   // changed to proceed in parallel, then this section will need
   // locking.
   Arena* save = current->type_arena();
   Arena* shared_type_arena = new (mtCompiler)Arena();
   current->set_type_arena(shared_type_arena);
   _shared_type_dict =
     new (shared_type_arena) Dict( (CmpKey)Type::cmp, (Hash)Type::uhash,
                                   shared_type_arena, 128 );
   current->set_type_dict(_shared_type_dict);
   // Make shared pre-built types.
   CONTROL = make(Control);      // Control only
   TOP     = make(Top);          // No values in set
   MEMORY  = make(Memory);       // Abstract store only
   ABIO    = make(Abio);         // State-of-machine only
   RETURN_ADDRESS=make(Return_Address);
   FLOAT   = make(FloatBot);     // All floats
   DOUBLE  = make(DoubleBot);    // All doubles
   BOTTOM  = make(Bottom);       // Everything
   HALF    = make(Half);         // Placeholder half of doublewide type
   TypeF::ZERO = TypeF::make(0.0); // Float 0 (positive zero)
   TypeF::ONE  = TypeF::make(1.0); // Float 1
   TypeD::ZERO = TypeD::make(0.0); // Double 0 (positive zero)
   TypeD::ONE  = TypeD::make(1.0); // Double 1
   TypeInt::MINUS_1 = TypeInt::make(-1);  // -1
   TypeInt::ZERO    = TypeInt::make( 0);  //  0
   TypeInt::ONE     = TypeInt::make( 1);  //  1
   TypeInt::BOOL    = TypeInt::make(0,1,   WidenMin);  // 0 or 1, FALSE or TRUE.
   TypeInt::CC      = TypeInt::make(-1, 1, WidenMin);  // -1, 0 or 1, condition codes
   TypeInt::CC_LT   = TypeInt::make(-1,-1, WidenMin);  // == TypeInt::MINUS_1
   TypeInt::CC_GT   = TypeInt::make( 1, 1, WidenMin);  // == TypeInt::ONE
   TypeInt::CC_EQ   = TypeInt::make( 0, 0, WidenMin);  // == TypeInt::ZERO
   TypeInt::CC_LE   = TypeInt::make(-1, 0, WidenMin);
   TypeInt::CC_GE   = TypeInt::make( 0, 1, WidenMin);  // == TypeInt::BOOL
   TypeInt::BYTE    = TypeInt::make(-128,127,     WidenMin); // Bytes
   TypeInt::UBYTE   = TypeInt::make(0, 255,       WidenMin); // Unsigned Bytes
   TypeInt::CHAR    = TypeInt::make(0,65535,      WidenMin); // Java chars
   TypeInt::SHORT   = TypeInt::make(-32768,32767, WidenMin); // Java shorts
   TypeInt::POS     = TypeInt::make(0,max_jint,   WidenMin); // Non-neg values
   TypeInt::POS1    = TypeInt::make(1,max_jint,   WidenMin); // Positive values
   TypeInt::INT     = TypeInt::make(min_jint,max_jint, WidenMax); // 32-bit integers
   TypeInt::SYMINT  = TypeInt::make(-max_jint,max_jint,WidenMin); // symmetric range
   // CmpL is overloaded both as the bytecode computation returning
   // a trinary (-1,0,+1) integer result AND as an efficient long
   // compare returning optimizer ideal-type flags.
   assert( TypeInt::CC_LT == TypeInt::MINUS_1, "types must match for CmpL to work" );
   assert( TypeInt::CC_GT == TypeInt::ONE,     "types must match for CmpL to work" );
   assert( TypeInt::CC_EQ == TypeInt::ZERO,    "types must match for CmpL to work" );
   assert( TypeInt::CC_GE == TypeInt::BOOL,    "types must match for CmpL to work" );
   assert( (juint)(TypeInt::CC->_hi - TypeInt::CC->_lo) <= SMALLINT, "CC is truly small");
   TypeLong::MINUS_1 = TypeLong::make(-1);        // -1
   TypeLong::ZERO    = TypeLong::make( 0);        //  0
   TypeLong::ONE     = TypeLong::make( 1);        //  1
   TypeLong::POS     = TypeLong::make(0,max_jlong, WidenMin); // Non-neg values
   TypeLong::LONG    = TypeLong::make(min_jlong,max_jlong,WidenMax); // 64-bit integers
   TypeLong::INT     = TypeLong::make((jlong)min_jint,(jlong)max_jint,WidenMin);
   TypeLong::UINT    = TypeLong::make(0,(jlong)max_juint,WidenMin);
   const Type **fboth =(const Type**)shared_type_arena->Amalloc_4(2*sizeof(Type*));
   fboth[0] = Type::CONTROL;
   fboth[1] = Type::CONTROL;
   TypeTuple::IFBOTH = TypeTuple::make( 2, fboth );
   const Type **ffalse =(const Type**)shared_type_arena->Amalloc_4(2*sizeof(Type*));
   ffalse[0] = Type::CONTROL;
   ffalse[1] = Type::TOP;
   TypeTuple::IFFALSE = TypeTuple::make( 2, ffalse );
   const Type **fneither =(const Type**)shared_type_arena->Amalloc_4(2*sizeof(Type*));
   fneither[0] = Type::TOP;
   fneither[1] = Type::TOP;
   TypeTuple::IFNEITHER = TypeTuple::make( 2, fneither );
   const Type **ftrue =(const Type**)shared_type_arena->Amalloc_4(2*sizeof(Type*));
   ftrue[0] = Type::TOP;
   ftrue[1] = Type::CONTROL;
   TypeTuple::IFTRUE = TypeTuple::make( 2, ftrue );
   const Type **floop =(const Type**)shared_type_arena->Amalloc_4(2*sizeof(Type*));
   floop[0] = Type::CONTROL;
   floop[1] = TypeInt::INT;
   TypeTuple::LOOPBODY = TypeTuple::make( 2, floop );
   TypePtr::NULL_PTR= TypePtr::make( AnyPtr, TypePtr::Null, 0 );
   TypePtr::NOTNULL = TypePtr::make( AnyPtr, TypePtr::NotNull, OffsetBot );
   TypePtr::BOTTOM  = TypePtr::make( AnyPtr, TypePtr::BotPTR, OffsetBot );
   TypeRawPtr::BOTTOM = TypeRawPtr::make( TypePtr::BotPTR );
   TypeRawPtr::NOTNULL= TypeRawPtr::make( TypePtr::NotNull );
   const Type **fmembar = TypeTuple::fields(0);
   TypeTuple::MEMBAR = TypeTuple::make(TypeFunc::Parms+0, fmembar);
   const Type **fsc = (const Type**)shared_type_arena->Amalloc_4(2*sizeof(Type*));
   fsc[0] = TypeInt::CC;
   fsc[1] = Type::MEMORY;
   TypeTuple::STORECONDITIONAL = TypeTuple::make(2, fsc);
   TypeInstPtr::NOTNULL = TypeInstPtr::make(TypePtr::NotNull, current->env()->Object_klass());
   TypeInstPtr::BOTTOM  = TypeInstPtr::make(TypePtr::BotPTR,  current->env()->Object_klass());
   TypeInstPtr::MIRROR  = TypeInstPtr::make(TypePtr::NotNull, current->env()->Class_klass());
   TypeInstPtr::MARK    = TypeInstPtr::make(TypePtr::BotPTR,  current->env()->Object_klass(),
                                            false, 0, oopDesc::mark_offset_in_bytes());
   TypeInstPtr::KLASS   = TypeInstPtr::make(TypePtr::BotPTR,  current->env()->Object_klass(),
                                            false, 0, oopDesc::klass_offset_in_bytes());
   TypeOopPtr::BOTTOM  = TypeOopPtr::make(TypePtr::BotPTR, OffsetBot, TypeOopPtr::InstanceBot);
   TypeMetadataPtr::BOTTOM = TypeMetadataPtr::make(TypePtr::BotPTR, NULL, OffsetBot);
   TypeNarrowOop::NULL_PTR = TypeNarrowOop::make( TypePtr::NULL_PTR );
   TypeNarrowOop::BOTTOM   = TypeNarrowOop::make( TypeInstPtr::BOTTOM );
   TypeNarrowKlass::NULL_PTR = TypeNarrowKlass::make( TypePtr::NULL_PTR );
   mreg2type[Op_Node] = Type::BOTTOM;
   mreg2type[Op_Set ] = 0;
   mreg2type[Op_RegN] = TypeNarrowOop::BOTTOM;
   mreg2type[Op_RegI] = TypeInt::INT;
   mreg2type[Op_RegP] = TypePtr::BOTTOM;
   mreg2type[Op_RegF] = Type::FLOAT;
   mreg2type[Op_RegD] = Type::DOUBLE;
   mreg2type[Op_RegL] = TypeLong::LONG;
   mreg2type[Op_RegFlags] = TypeInt::CC;
   TypeAryPtr::RANGE   = TypeAryPtr::make( TypePtr::BotPTR, TypeAry::make(Type::BOTTOM,TypeInt::POS), NULL /* current->env()->Object_klass() */, false, arrayOopDesc::length_offset_in_bytes());
   TypeAryPtr::NARROWOOPS = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(TypeNarrowOop::BOTTOM, TypeInt::POS), NULL /*ciArrayKlass::make(o)*/,  false,  Type::OffsetBot);
 #ifdef _LP64
   if (UseCompressedOops) {
     assert(TypeAryPtr::NARROWOOPS->is_ptr_to_narrowoop(), "array of narrow oops must be ptr to narrow oop");
     TypeAryPtr::OOPS  = TypeAryPtr::NARROWOOPS;
   } else
 #endif
   {
     // There is no shared klass for Object[].  See note in TypeAryPtr::klass().
     TypeAryPtr::OOPS  = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(TypeInstPtr::BOTTOM,TypeInt::POS), NULL /*ciArrayKlass::make(o)*/,  false,  Type::OffsetBot);
   }
   TypeAryPtr::BYTES   = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(TypeInt::BYTE      ,TypeInt::POS), ciTypeArrayKlass::make(T_BYTE),   true,  Type::OffsetBot);
   TypeAryPtr::SHORTS  = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(TypeInt::SHORT     ,TypeInt::POS), ciTypeArrayKlass::make(T_SHORT),  true,  Type::OffsetBot);
   TypeAryPtr::CHARS   = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(TypeInt::CHAR      ,TypeInt::POS), ciTypeArrayKlass::make(T_CHAR),   true,  Type::OffsetBot);
   TypeAryPtr::INTS    = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(TypeInt::INT       ,TypeInt::POS), ciTypeArrayKlass::make(T_INT),    true,  Type::OffsetBot);
   TypeAryPtr::LONGS   = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(TypeLong::LONG     ,TypeInt::POS), ciTypeArrayKlass::make(T_LONG),   true,  Type::OffsetBot);
   TypeAryPtr::FLOATS  = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(Type::FLOAT        ,TypeInt::POS), ciTypeArrayKlass::make(T_FLOAT),  true,  Type::OffsetBot);
   TypeAryPtr::DOUBLES = TypeAryPtr::make(TypePtr::BotPTR, TypeAry::make(Type::DOUBLE       ,TypeInt::POS), ciTypeArrayKlass::make(T_DOUBLE), true,  Type::OffsetBot);
   // Nobody should ask _array_body_type[T_NARROWOOP]. Use NULL as assert.
   TypeAryPtr::_array_body_type[T_NARROWOOP] = NULL;
   TypeAryPtr::_array_body_type[T_OBJECT]  = TypeAryPtr::OOPS;
   TypeAryPtr::_array_body_type[T_ARRAY]   = TypeAryPtr::OOPS; // arrays are stored in oop arrays
   TypeAryPtr::_array_body_type[T_BYTE]    = TypeAryPtr::BYTES;
   TypeAryPtr::_array_body_type[T_BOOLEAN] = TypeAryPtr::BYTES;  // boolean[] is a byte array
   TypeAryPtr::_array_body_type[T_SHORT]   = TypeAryPtr::SHORTS;
   TypeAryPtr::_array_body_type[T_CHAR]    = TypeAryPtr::CHARS;
   TypeAryPtr::_array_body_type[T_INT]     = TypeAryPtr::INTS;
   TypeAryPtr::_array_body_type[T_LONG]    = TypeAryPtr::LONGS;
   TypeAryPtr::_array_body_type[T_FLOAT]   = TypeAryPtr::FLOATS;
   TypeAryPtr::_array_body_type[T_DOUBLE]  = TypeAryPtr::DOUBLES;
   TypeKlassPtr::OBJECT = TypeKlassPtr::make( TypePtr::NotNull, current->env()->Object_klass(), 0 );
   TypeKlassPtr::OBJECT_OR_NULL = TypeKlassPtr::make( TypePtr::BotPTR, current->env()->Object_klass(), 0 );
   const Type **fi2c = TypeTuple::fields(2);
   fi2c[TypeFunc::Parms+0] = TypeInstPtr::BOTTOM; // Method*
   fi2c[TypeFunc::Parms+1] = TypeRawPtr::BOTTOM; // argument pointer
   TypeTuple::START_I2C = TypeTuple::make(TypeFunc::Parms+2, fi2c);
   const Type **intpair = TypeTuple::fields(2);
   intpair[0] = TypeInt::INT;
   intpair[1] = TypeInt::INT;
   TypeTuple::INT_PAIR = TypeTuple::make(2, intpair);
   const Type **longpair = TypeTuple::fields(2);
   longpair[0] = TypeLong::LONG;
   longpair[1] = TypeLong::LONG;
   TypeTuple::LONG_PAIR = TypeTuple::make(2, longpair);
   _const_basic_type[T_NARROWOOP]   = TypeNarrowOop::BOTTOM;
   _const_basic_type[T_NARROWKLASS] = Type::BOTTOM;
   _const_basic_type[T_BOOLEAN]     = TypeInt::BOOL;
   _const_basic_type[T_CHAR]        = TypeInt::CHAR;
   _const_basic_type[T_BYTE]        = TypeInt::BYTE;
   _const_basic_type[T_SHORT]       = TypeInt::SHORT;
   _const_basic_type[T_INT]         = TypeInt::INT;
   _const_basic_type[T_LONG]        = TypeLong::LONG;
   _const_basic_type[T_FLOAT]       = Type::FLOAT;
   _const_basic_type[T_DOUBLE]      = Type::DOUBLE;
   _const_basic_type[T_OBJECT]      = TypeInstPtr::BOTTOM;
   _const_basic_type[T_ARRAY]       = TypeInstPtr::BOTTOM; // there is no separate bottom for arrays
   _const_basic_type[T_VOID]        = TypePtr::NULL_PTR;   // reflection represents void this way
   _const_basic_type[T_ADDRESS]     = TypeRawPtr::BOTTOM;  // both interpreter return addresses & random raw ptrs
   _const_basic_type[T_CONFLICT]    = Type::BOTTOM;        // why not?
   _zero_type[T_NARROWOOP]   = TypeNarrowOop::NULL_PTR;
   _zero_type[T_NARROWKLASS] = TypeNarrowKlass::NULL_PTR;
   _zero_type[T_BOOLEAN]     = TypeInt::ZERO;     // false == 0
   _zero_type[T_CHAR]        = TypeInt::ZERO;     // '\0' == 0
   _zero_type[T_BYTE]        = TypeInt::ZERO;     // 0x00 == 0
   _zero_type[T_SHORT]       = TypeInt::ZERO;     // 0x0000 == 0
   _zero_type[T_INT]         = TypeInt::ZERO;
   _zero_type[T_LONG]        = TypeLong::ZERO;
   _zero_type[T_FLOAT]       = TypeF::ZERO;
   _zero_type[T_DOUBLE]      = TypeD::ZERO;
   _zero_type[T_OBJECT]      = TypePtr::NULL_PTR;
   _zero_type[T_ARRAY]       = TypePtr::NULL_PTR; // null array is null oop
   _zero_type[T_ADDRESS]     = TypePtr::NULL_PTR; // raw pointers use the same null
   _zero_type[T_VOID]        = Type::TOP;         // the only void value is no value at all
   // get_zero_type() should not happen for T_CONFLICT
   _zero_type[T_CONFLICT]= NULL;
   // Vector predefined types, it needs initialized _const_basic_type[].
   if (Matcher::vector_size_supported(T_BYTE,4)) {
     TypeVect::VECTS = TypeVect::make(T_BYTE,4);
   }
   if (Matcher::vector_size_supported(T_FLOAT,2)) {
     TypeVect::VECTD = TypeVect::make(T_FLOAT,2);
   }
   if (Matcher::vector_size_supported(T_FLOAT,4)) {
     TypeVect::VECTX = TypeVect::make(T_FLOAT,4);
   }
   if (Matcher::vector_size_supported(T_FLOAT,8)) {
     TypeVect::VECTY = TypeVect::make(T_FLOAT,8);
   }
   mreg2type[Op_VecS] = TypeVect::VECTS;
   mreg2type[Op_VecD] = TypeVect::VECTD;
   mreg2type[Op_VecX] = TypeVect::VECTX;
   mreg2type[Op_VecY] = TypeVect::VECTY;
   // Restore working type arena.
   current->set_type_arena(save);
   current->set_type_dict(NULL);
 }
 //------------------------------Initialize-------------------------------------
 void Type::Initialize(Compile* current) {
   assert(current->type_arena() != NULL, "must have created type arena");
   if (_shared_type_dict == NULL) {
     Initialize_shared(current);
   }
   Arena* type_arena = current->type_arena();
   // Create the hash-cons'ing dictionary with top-level storage allocation
   Dict *tdic = new (type_arena) Dict( (CmpKey)Type::cmp,(Hash)Type::uhash, type_arena, 128 );
   current->set_type_dict(tdic);
   // Transfer the shared types.
   DictI i(_shared_type_dict);
   for( ; i.test(); ++i ) {
     Type* t = (Type*)i._value;
     tdic->Insert(t,t);  // New Type, insert into Type table
   }
 }
 //------------------------------hashcons---------------------------------------
 // Do the hash-cons trick.  If the Type already exists in the type table,
 // delete the current Type and return the existing Type.  Otherwise stick the
 // current Type in the Type table.
 const Type *Type::hashcons(void) {
   debug_only(base());           // Check the assertion in Type::base().
   // Look up the Type in the Type dictionary
   Dict *tdic = type_dict();
   Type* old = (Type*)(tdic->Insert(this, this, false));
   if( old ) {                   // Pre-existing Type?
     if( old != this )           // Yes, this guy is not the pre-existing?
       delete this;              // Yes, Nuke this guy
     assert( old->_dual, "" );
     return old;                 // Return pre-existing
   }
   // Every type has a dual (to make my lattice symmetric).
   // Since we just discovered a new Type, compute its dual right now.
   assert( !_dual, "" );         // No dual yet
   _dual = xdual();              // Compute the dual
   if( cmp(this,_dual)==0 ) {    // Handle self-symmetric
     _dual = this;
     return this;
   }
   assert( !_dual->_dual, "" );  // No reverse dual yet
   assert( !(*tdic)[_dual], "" ); // Dual not in type system either
   // New Type, insert into Type table
   tdic->Insert((void*)_dual,(void*)_dual);
   ((Type*)_dual)->_dual = this; // Finish up being symmetric
 #ifdef ASSERT
   Type *dual_dual = (Type*)_dual->xdual();
   assert( eq(dual_dual), "xdual(xdual()) should be identity" );
   delete dual_dual;
 #endif
   return this;                  // Return new Type
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool Type::eq( const Type * ) const {
   return true;                  // Nothing else can go wrong
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int Type::hash(void) const {
   return _base;
 }
 //------------------------------is_finite--------------------------------------
 // Has a finite value
 bool Type::is_finite() const {
   return false;
 }
 //------------------------------is_nan-----------------------------------------
 // Is not a number (NaN)
 bool Type::is_nan()    const {
   return false;
 }
 //----------------------interface_vs_oop---------------------------------------
 #ifdef ASSERT
 bool Type::interface_vs_oop(const Type *t) const {
   bool result = false;
   const TypePtr* this_ptr = this->make_ptr(); // In case it is narrow_oop
   const TypePtr*    t_ptr =    t->make_ptr();
   if( this_ptr == NULL || t_ptr == NULL )
     return result;
   const TypeInstPtr* this_inst = this_ptr->isa_instptr();
   const TypeInstPtr*    t_inst =    t_ptr->isa_instptr();
   if( this_inst && this_inst->is_loaded() && t_inst && t_inst->is_loaded() ) {
     bool this_interface = this_inst->klass()->is_interface();
     bool    t_interface =    t_inst->klass()->is_interface();
     result = this_interface ^ t_interface;
   }
   return result;
 }
 #endif
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  NOT virtual.  It enforces that meet is
 // commutative and the lattice is symmetric.
 const Type *Type::meet( const Type *t ) const {
   if (isa_narrowoop() && t->isa_narrowoop()) {
     const Type* result = make_ptr()->meet(t->make_ptr());
     return result->make_narrowoop();
   }
   if (isa_narrowklass() && t->isa_narrowklass()) {
     const Type* result = make_ptr()->meet(t->make_ptr());
     return result->make_narrowklass();
   }
   const Type *mt = xmeet(t);
   if (isa_narrowoop() || t->isa_narrowoop()) return mt;
   if (isa_narrowklass() || t->isa_narrowklass()) return mt;
 #ifdef ASSERT
   assert( mt == t->xmeet(this), "meet not commutative" );
   const Type* dual_join = mt->_dual;
   const Type *t2t    = dual_join->xmeet(t->_dual);
   const Type *t2this = dual_join->xmeet(   _dual);
   // Interface meet Oop is Not Symmetric:
   // Interface:AnyNull meet Oop:AnyNull == Interface:AnyNull
   // Interface:NotNull meet Oop:NotNull == java/lang/Object:NotNull
   if( !interface_vs_oop(t) && (t2t != t->_dual || t2this != _dual) ) {
     tty->print_cr("=== Meet Not Symmetric ===");
     tty->print("t   =                   ");         t->dump(); tty->cr();
     tty->print("this=                   ");            dump(); tty->cr();
     tty->print("mt=(t meet this)=       ");        mt->dump(); tty->cr();
     tty->print("t_dual=                 ");  t->_dual->dump(); tty->cr();
     tty->print("this_dual=              ");     _dual->dump(); tty->cr();
     tty->print("mt_dual=                "); mt->_dual->dump(); tty->cr();
     tty->print("mt_dual meet t_dual=    "); t2t      ->dump(); tty->cr();
     tty->print("mt_dual meet this_dual= "); t2this   ->dump(); tty->cr();
     fatal("meet not symmetric" );
   }
 #endif
   return mt;
 }
 //------------------------------xmeet------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *Type::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Meeting TOP with anything?
   if( _base == Top ) return t;
   // Meeting BOTTOM with anything?
   if( _base == Bottom ) return BOTTOM;
   // Current "this->_base" is one of: Bad, Multi, Control, Top,
   // Abio, Abstore, Floatxxx, Doublexxx, Bottom, lastype.
   switch (t->base()) {  // Switch on original type
   // Cut in half the number of cases I must handle.  Only need cases for when
   // the given enum "t->type" is less than or equal to the local enum "type".
   case FloatCon:
   case DoubleCon:
   case Int:
   case Long:
     return t->xmeet(this);
   case OopPtr:
     return t->xmeet(this);
   case InstPtr:
     return t->xmeet(this);
   case MetadataPtr:
   case KlassPtr:
     return t->xmeet(this);
   case AryPtr:
     return t->xmeet(this);
   case NarrowOop:
     return t->xmeet(this);
   case NarrowKlass:
     return t->xmeet(this);
   case Bad:                     // Type check
   default:                      // Bogus type not in lattice
     typerr(t);
     return Type::BOTTOM;
   case Bottom:                  // Ye Olde Default
     return t;
   case FloatTop:
     if( _base == FloatTop ) return this;
   case FloatBot:                // Float
     if( _base == FloatBot || _base == FloatTop ) return FLOAT;
     if( _base == DoubleTop || _base == DoubleBot ) return Type::BOTTOM;
     typerr(t);
     return Type::BOTTOM;
   case DoubleTop:
     if( _base == DoubleTop ) return this;
   case DoubleBot:               // Double
     if( _base == DoubleBot || _base == DoubleTop ) return DOUBLE;
     if( _base == FloatTop || _base == FloatBot ) return Type::BOTTOM;
     typerr(t);
     return Type::BOTTOM;
   // These next few cases must match exactly or it is a compile-time error.
   case Control:                 // Control of code
   case Abio:                    // State of world outside of program
   case Memory:
     if( _base == t->_base )  return this;
     typerr(t);
     return Type::BOTTOM;
   case Top:                     // Top of the lattice
     return this;
   }
   // The type is unchanged
   return this;
 }
 //-----------------------------filter------------------------------------------
 const Type *Type::filter( const Type *kills ) const {
   const Type* ft = join(kills);
   if (ft->empty())
     return Type::TOP;           // Canonical empty value
   return ft;
 }
 //------------------------------xdual------------------------------------------
 // Compute dual right now.
 const Type::TYPES Type::dual_type[Type::lastype] = {
   Bad,          // Bad
   Control,      // Control
   Bottom,       // Top
   Bad,          // Int - handled in v-call
   Bad,          // Long - handled in v-call
   Half,         // Half
   Bad,          // NarrowOop - handled in v-call
   Bad,          // NarrowKlass - handled in v-call
   Bad,          // Tuple - handled in v-call
   Bad,          // Array - handled in v-call
   Bad,          // VectorS - handled in v-call
   Bad,          // VectorD - handled in v-call
   Bad,          // VectorX - handled in v-call
   Bad,          // VectorY - handled in v-call
   Bad,          // AnyPtr - handled in v-call
   Bad,          // RawPtr - handled in v-call
   Bad,          // OopPtr - handled in v-call
   Bad,          // InstPtr - handled in v-call
   Bad,          // AryPtr - handled in v-call
   Bad,          //  MetadataPtr - handled in v-call
   Bad,          // KlassPtr - handled in v-call
   Bad,          // Function - handled in v-call
   Abio,         // Abio
   Return_Address,// Return_Address
   Memory,       // Memory
   FloatBot,     // FloatTop
   FloatCon,     // FloatCon
   FloatTop,     // FloatBot
   DoubleBot,    // DoubleTop
   DoubleCon,    // DoubleCon
   DoubleTop,    // DoubleBot
   Top           // Bottom
 };
 const Type *Type::xdual() const {
   // Note: the base() accessor asserts the sanity of _base.
   assert(_type_info[base()].dual_type != Bad, "implement with v-call");
   return new Type(_type_info[_base].dual_type);
 }
 //------------------------------has_memory-------------------------------------
 bool Type::has_memory() const {
   Type::TYPES tx = base();
   if (tx == Memory) return true;
   if (tx == Tuple) {
     const TypeTuple *t = is_tuple();
     for (uint i=0; i < t->cnt(); i++) {
       tx = t->field_at(i)->base();
       if (tx == Memory)  return true;
     }
   }
   return false;
 }
 #ifndef PRODUCT
 //------------------------------dump2------------------------------------------
 void Type::dump2( Dict &d, uint depth, outputStream *st ) const {
   st->print(_type_info[_base].msg);
 }
 //------------------------------dump-------------------------------------------
 void Type::dump_on(outputStream *st) const {
   ResourceMark rm;
   Dict d(cmpkey,hashkey);       // Stop recursive type dumping
   dump2(d,1, st);
   if (is_ptr_to_narrowoop()) {
     st->print(" [narrow]");
   } else if (is_ptr_to_narrowklass()) {
     st->print(" [narrowklass]");
   }
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants (Ldi nodes).  Singletons are integer, float or double constants.
 bool Type::singleton(void) const {
   return _base == Top || _base == Half;
 }
 //------------------------------empty------------------------------------------
 // TRUE if Type is a type with no values, FALSE otherwise.
 bool Type::empty(void) const {
   switch (_base) {
   case DoubleTop:
   case FloatTop:
   case Top:
     return true;
   case Half:
   case Abio:
   case Return_Address:
   case Memory:
   case Bottom:
   case FloatBot:
   case DoubleBot:
     return false;  // never a singleton, therefore never empty
   }
   ShouldNotReachHere();
   return false;
 }
 //------------------------------dump_stats-------------------------------------
 // Dump collected statistics to stderr
 #ifndef PRODUCT
 void Type::dump_stats() {
   tty->print("Types made: %d\n", type_dict()->Size());
 }
 #endif
 //------------------------------typerr-----------------------------------------
 void Type::typerr( const Type *t ) const {
 #ifndef PRODUCT
   tty->print("\nError mixing types: ");
   dump();
   tty->print(" and ");
   t->dump();
   tty->print("\n");
 #endif
   ShouldNotReachHere();
 }
 //=============================================================================
 // Convenience common pre-built types.
 const TypeF *TypeF::ZERO;       // Floating point zero
 const TypeF *TypeF::ONE;        // Floating point one
 //------------------------------make-------------------------------------------
 // Create a float constant
 const TypeF *TypeF::make(float f) {
   return (TypeF*)(new TypeF(f))->hashcons();
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeF::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is FloatCon
   switch (t->base()) {          // Switch on original type
   case AnyPtr:                  // Mixing with oops happens when javac
   case RawPtr:                  // reuses local variables
   case OopPtr:
   case InstPtr:
   case AryPtr:
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
   case NarrowKlass:
   case Int:
   case Long:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case FloatBot:
     return t;
   default:                      // All else is a mistake
     typerr(t);
   case FloatCon:                // Float-constant vs Float-constant?
     if( jint_cast(_f) != jint_cast(t->getf()) )         // unequal constants?
                                 // must compare bitwise as positive zero, negative zero and NaN have
                                 // all the same representation in C++
       return FLOAT;             // Return generic float
                                 // Equal constants
   case Top:
   case FloatTop:
     break;                      // Return the float constant
   }
   return this;                  // Return the float constant
 }
 //------------------------------xdual------------------------------------------
 // Dual: symmetric
 const Type *TypeF::xdual() const {
   return this;
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeF::eq( const Type *t ) const {
   if( g_isnan(_f) ||
       g_isnan(t->getf()) ) {
     // One or both are NANs.  If both are NANs return true, else false.
     return (g_isnan(_f) && g_isnan(t->getf()));
   }
   if (_f == t->getf()) {
     // (NaN is impossible at this point, since it is not equal even to itself)
     if (_f == 0.0) {
       // difference between positive and negative zero
       if (jint_cast(_f) != jint_cast(t->getf()))  return false;
     }
     return true;
   }
   return false;
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeF::hash(void) const {
   return *(int*)(&_f);
 }
 //------------------------------is_finite--------------------------------------
 // Has a finite value
 bool TypeF::is_finite() const {
   return g_isfinite(getf()) != 0;
 }
 //------------------------------is_nan-----------------------------------------
 // Is not a number (NaN)
 bool TypeF::is_nan()    const {
   return g_isnan(getf()) != 0;
 }
 //------------------------------dump2------------------------------------------
 // Dump float constant Type
 #ifndef PRODUCT
 void TypeF::dump2( Dict &d, uint depth, outputStream *st ) const {
   Type::dump2(d,depth, st);
   st->print("%f", _f);
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants (Ldi nodes).  Singletons are integer, float or double constants
 // or a single symbol.
 bool TypeF::singleton(void) const {
   return true;                  // Always a singleton
 }
 bool TypeF::empty(void) const {
   return false;                 // always exactly a singleton
 }
 //=============================================================================
 // Convenience common pre-built types.
 const TypeD *TypeD::ZERO;       // Floating point zero
 const TypeD *TypeD::ONE;        // Floating point one
 //------------------------------make-------------------------------------------
 const TypeD *TypeD::make(double d) {
   return (TypeD*)(new TypeD(d))->hashcons();
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeD::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is DoubleCon
   switch (t->base()) {          // Switch on original type
   case AnyPtr:                  // Mixing with oops happens when javac
   case RawPtr:                  // reuses local variables
   case OopPtr:
   case InstPtr:
   case AryPtr:
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
   case NarrowKlass:
   case Int:
   case Long:
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case DoubleBot:
     return t;
   default:                      // All else is a mistake
     typerr(t);
   case DoubleCon:               // Double-constant vs Double-constant?
     if( jlong_cast(_d) != jlong_cast(t->getd()) )       // unequal constants? (see comment in TypeF::xmeet)
       return DOUBLE;            // Return generic double
   case Top:
   case DoubleTop:
     break;
   }
   return this;                  // Return the double constant
 }
 //------------------------------xdual------------------------------------------
 // Dual: symmetric
 const Type *TypeD::xdual() const {
   return this;
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeD::eq( const Type *t ) const {
   if( g_isnan(_d) ||
       g_isnan(t->getd()) ) {
     // One or both are NANs.  If both are NANs return true, else false.
     return (g_isnan(_d) && g_isnan(t->getd()));
   }
   if (_d == t->getd()) {
     // (NaN is impossible at this point, since it is not equal even to itself)
     if (_d == 0.0) {
       // difference between positive and negative zero
       if (jlong_cast(_d) != jlong_cast(t->getd()))  return false;
     }
     return true;
   }
   return false;
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeD::hash(void) const {
   return *(int*)(&_d);
 }
 //------------------------------is_finite--------------------------------------
 // Has a finite value
 bool TypeD::is_finite() const {
   return g_isfinite(getd()) != 0;
 }
 //------------------------------is_nan-----------------------------------------
 // Is not a number (NaN)
 bool TypeD::is_nan()    const {
   return g_isnan(getd()) != 0;
 }
 //------------------------------dump2------------------------------------------
 // Dump double constant Type
 #ifndef PRODUCT
 void TypeD::dump2( Dict &d, uint depth, outputStream *st ) const {
   Type::dump2(d,depth,st);
   st->print("%f", _d);
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants (Ldi nodes).  Singletons are integer, float or double constants
 // or a single symbol.
 bool TypeD::singleton(void) const {
   return true;                  // Always a singleton
 }
 bool TypeD::empty(void) const {
   return false;                 // always exactly a singleton
 }
 //=============================================================================
 // Convience common pre-built types.
 const TypeInt *TypeInt::MINUS_1;// -1
 const TypeInt *TypeInt::ZERO;   // 0
 const TypeInt *TypeInt::ONE;    // 1
 const TypeInt *TypeInt::BOOL;   // 0 or 1, FALSE or TRUE.
 const TypeInt *TypeInt::CC;     // -1,0 or 1, condition codes
 const TypeInt *TypeInt::CC_LT;  // [-1]  == MINUS_1
 const TypeInt *TypeInt::CC_GT;  // [1]   == ONE
 const TypeInt *TypeInt::CC_EQ;  // [0]   == ZERO
 const TypeInt *TypeInt::CC_LE;  // [-1,0]
 const TypeInt *TypeInt::CC_GE;  // [0,1] == BOOL (!)
 const TypeInt *TypeInt::BYTE;   // Bytes, -128 to 127
 const TypeInt *TypeInt::UBYTE;  // Unsigned Bytes, 0 to 255
 const TypeInt *TypeInt::CHAR;   // Java chars, 0-65535
 const TypeInt *TypeInt::SHORT;  // Java shorts, -32768-32767
 const TypeInt *TypeInt::POS;    // Positive 32-bit integers or zero
 const TypeInt *TypeInt::POS1;   // Positive 32-bit integers
 const TypeInt *TypeInt::INT;    // 32-bit integers
 const TypeInt *TypeInt::SYMINT; // symmetric range [-max_jint..max_jint]
 //------------------------------TypeInt----------------------------------------
 TypeInt::TypeInt( jint lo, jint hi, int w ) : Type(Int), _lo(lo), _hi(hi), _widen(w) {
 }
 //------------------------------make-------------------------------------------
 const TypeInt *TypeInt::make( jint lo ) {
   return (TypeInt*)(new TypeInt(lo,lo,WidenMin))->hashcons();
 }
 static int normalize_int_widen( jint lo, jint hi, int w ) {
   // Certain normalizations keep us sane when comparing types.
   // The 'SMALLINT' covers constants and also CC and its relatives.
   if (lo <= hi) {
     if ((juint)(hi - lo) <= SMALLINT)  w = Type::WidenMin;
     if ((juint)(hi - lo) >= max_juint) w = Type::WidenMax; // TypeInt::INT
   } else {
     if ((juint)(lo - hi) <= SMALLINT)  w = Type::WidenMin;
     if ((juint)(lo - hi) >= max_juint) w = Type::WidenMin; // dual TypeInt::INT
   }
   return w;
 }
 const TypeInt *TypeInt::make( jint lo, jint hi, int w ) {
   w = normalize_int_widen(lo, hi, w);
   return (TypeInt*)(new TypeInt(lo,hi,w))->hashcons();
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type representation object
 // with reference count equal to the number of Types pointing at it.
 // Caller should wrap a Types around it.
 const Type *TypeInt::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type?
   // Currently "this->_base" is a TypeInt
   switch (t->base()) {          // Switch on original type
   case AnyPtr:                  // Mixing with oops happens when javac
   case RawPtr:                  // reuses local variables
   case OopPtr:
   case InstPtr:
   case AryPtr:
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
   case NarrowKlass:
   case Long:
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   default:                      // All else is a mistake
     typerr(t);
   case Top:                     // No change
     return this;
   case Int:                     // Int vs Int?
     break;
   }
   // Expand covered set
   const TypeInt *r = t->is_int();
   return make( MIN2(_lo,r->_lo), MAX2(_hi,r->_hi), MAX2(_widen,r->_widen) );
 }
 //------------------------------xdual------------------------------------------
 // Dual: reverse hi & lo; flip widen
 const Type *TypeInt::xdual() const {
   int w = normalize_int_widen(_hi,_lo, WidenMax-_widen);
   return new TypeInt(_hi,_lo,w);
 }
 //------------------------------widen------------------------------------------
 // Only happens for optimistic top-down optimizations.
 const Type *TypeInt::widen( const Type *old, const Type* limit ) const {
   // Coming from TOP or such; no widening
   if( old->base() != Int ) return this;
   const TypeInt *ot = old->is_int();
   // If new guy is equal to old guy, no widening
   if( _lo == ot->_lo && _hi == ot->_hi )
     return old;
   // If new guy contains old, then we widened
   if( _lo <= ot->_lo && _hi >= ot->_hi ) {
     // New contains old
     // If new guy is already wider than old, no widening
     if( _widen > ot->_widen ) return this;
     // If old guy was a constant, do not bother
     if (ot->_lo == ot->_hi)  return this;
     // Now widen new guy.
     // Check for widening too far
     if (_widen == WidenMax) {
       int max = max_jint;
       int min = min_jint;
       if (limit->isa_int()) {
         max = limit->is_int()->_hi;
         min = limit->is_int()->_lo;
       }
       if (min < _lo && _hi < max) {
         // If neither endpoint is extremal yet, push out the endpoint
         // which is closer to its respective limit.
         if (_lo >= 0 ||                 // easy common case
             (juint)(_lo - min) >= (juint)(max - _hi)) {
           // Try to widen to an unsigned range type of 31 bits:
           return make(_lo, max, WidenMax);
         } else {
           return make(min, _hi, WidenMax);
         }
       }
       return TypeInt::INT;
     }
     // Returned widened new guy
     return make(_lo,_hi,_widen+1);
   }
   // If old guy contains new, then we probably widened too far & dropped to
   // bottom.  Return the wider fellow.
   if ( ot->_lo <= _lo && ot->_hi >= _hi )
     return old;
   //fatal("Integer value range is not subset");
   //return this;
   return TypeInt::INT;
 }
 //------------------------------narrow---------------------------------------
 // Only happens for pessimistic optimizations.
 const Type *TypeInt::narrow( const Type *old ) const {
   if (_lo >= _hi)  return this;   // already narrow enough
   if (old == NULL)  return this;
   const TypeInt* ot = old->isa_int();
   if (ot == NULL)  return this;
   jint olo = ot->_lo;
   jint ohi = ot->_hi;
   // If new guy is equal to old guy, no narrowing
   if (_lo == olo && _hi == ohi)  return old;
   // If old guy was maximum range, allow the narrowing
   if (olo == min_jint && ohi == max_jint)  return this;
   if (_lo < olo || _hi > ohi)
     return this;                // doesn't narrow; pretty wierd
   // The new type narrows the old type, so look for a "death march".
   // See comments on PhaseTransform::saturate.
   juint nrange = _hi - _lo;
   juint orange = ohi - olo;
   if (nrange < max_juint - 1 && nrange > (orange >> 1) + (SMALLINT*2)) {
     // Use the new type only if the range shrinks a lot.
     // We do not want the optimizer computing 2^31 point by point.
     return old;
   }
   return this;
 }
 //-----------------------------filter------------------------------------------
 const Type *TypeInt::filter( const Type *kills ) const {
   const TypeInt* ft = join(kills)->isa_int();
   if (ft == NULL || ft->empty())
     return Type::TOP;           // Canonical empty value
   if (ft->_widen < this->_widen) {
     // Do not allow the value of kill->_widen to affect the outcome.
     // The widen bits must be allowed to run freely through the graph.
     ft = TypeInt::make(ft->_lo, ft->_hi, this->_widen);
   }
   return ft;
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeInt::eq( const Type *t ) const {
   const TypeInt *r = t->is_int(); // Handy access
   return r->_lo == _lo && r->_hi == _hi && r->_widen == _widen;
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeInt::hash(void) const {
   return _lo+_hi+_widen+(int)Type::Int;
 }
 //------------------------------is_finite--------------------------------------
 // Has a finite value
 bool TypeInt::is_finite() const {
   return true;
 }
 //------------------------------dump2------------------------------------------
 // Dump TypeInt
 #ifndef PRODUCT
 static const char* intname(char* buf, jint n) {
   if (n == min_jint)
     return "min";
   else if (n < min_jint + 10000)
     sprintf(buf, "min+" INT32_FORMAT, n - min_jint);
   else if (n == max_jint)
     return "max";
   else if (n > max_jint - 10000)
     sprintf(buf, "max-" INT32_FORMAT, max_jint - n);
   else
     sprintf(buf, INT32_FORMAT, n);
   return buf;
 }
 void TypeInt::dump2( Dict &d, uint depth, outputStream *st ) const {
   char buf[40], buf2[40];
   if (_lo == min_jint && _hi == max_jint)
     st->print("int");
   else if (is_con())
     st->print("int:%s", intname(buf, get_con()));
   else if (_lo == BOOL->_lo && _hi == BOOL->_hi)
     st->print("bool");
   else if (_lo == BYTE->_lo && _hi == BYTE->_hi)
     st->print("byte");
   else if (_lo == CHAR->_lo && _hi == CHAR->_hi)
     st->print("char");
   else if (_lo == SHORT->_lo && _hi == SHORT->_hi)
     st->print("short");
   else if (_hi == max_jint)
     st->print("int:>=%s", intname(buf, _lo));
   else if (_lo == min_jint)
     st->print("int:<=%s", intname(buf, _hi));
   else
     st->print("int:%s..%s", intname(buf, _lo), intname(buf2, _hi));
   if (_widen != 0 && this != TypeInt::INT)
     st->print(":%.*s", _widen, "wwww");
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants.
 bool TypeInt::singleton(void) const {
   return _lo >= _hi;
 }
 bool TypeInt::empty(void) const {
   return _lo > _hi;
 }
 //=============================================================================
 // Convenience common pre-built types.
 const TypeLong *TypeLong::MINUS_1;// -1
 const TypeLong *TypeLong::ZERO; // 0
 const TypeLong *TypeLong::ONE;  // 1
 const TypeLong *TypeLong::POS;  // >=0
 const TypeLong *TypeLong::LONG; // 64-bit integers
 const TypeLong *TypeLong::INT;  // 32-bit subrange
 const TypeLong *TypeLong::UINT; // 32-bit unsigned subrange
 //------------------------------TypeLong---------------------------------------
 TypeLong::TypeLong( jlong lo, jlong hi, int w ) : Type(Long), _lo(lo), _hi(hi), _widen(w) {
 }
 //------------------------------make-------------------------------------------
 const TypeLong *TypeLong::make( jlong lo ) {
   return (TypeLong*)(new TypeLong(lo,lo,WidenMin))->hashcons();
 }
 static int normalize_long_widen( jlong lo, jlong hi, int w ) {
   // Certain normalizations keep us sane when comparing types.
   // The 'SMALLINT' covers constants.
   if (lo <= hi) {
     if ((julong)(hi - lo) <= SMALLINT)   w = Type::WidenMin;
     if ((julong)(hi - lo) >= max_julong) w = Type::WidenMax; // TypeLong::LONG
   } else {
     if ((julong)(lo - hi) <= SMALLINT)   w = Type::WidenMin;
     if ((julong)(lo - hi) >= max_julong) w = Type::WidenMin; // dual TypeLong::LONG
   }
   return w;
 }
 const TypeLong *TypeLong::make( jlong lo, jlong hi, int w ) {
   w = normalize_long_widen(lo, hi, w);
   return (TypeLong*)(new TypeLong(lo,hi,w))->hashcons();
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type representation object
 // with reference count equal to the number of Types pointing at it.
 // Caller should wrap a Types around it.
 const Type *TypeLong::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type?
   // Currently "this->_base" is a TypeLong
   switch (t->base()) {          // Switch on original type
   case AnyPtr:                  // Mixing with oops happens when javac
   case RawPtr:                  // reuses local variables
   case OopPtr:
   case InstPtr:
   case AryPtr:
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
   case NarrowKlass:
   case Int:
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   default:                      // All else is a mistake
     typerr(t);
   case Top:                     // No change
     return this;
   case Long:                    // Long vs Long?
     break;
   }
   // Expand covered set
   const TypeLong *r = t->is_long(); // Turn into a TypeLong
   return make( MIN2(_lo,r->_lo), MAX2(_hi,r->_hi), MAX2(_widen,r->_widen) );
 }
 //------------------------------xdual------------------------------------------
 // Dual: reverse hi & lo; flip widen
 const Type *TypeLong::xdual() const {
   int w = normalize_long_widen(_hi,_lo, WidenMax-_widen);
   return new TypeLong(_hi,_lo,w);
 }
 //------------------------------widen------------------------------------------
 // Only happens for optimistic top-down optimizations.
 const Type *TypeLong::widen( const Type *old, const Type* limit ) const {
   // Coming from TOP or such; no widening
   if( old->base() != Long ) return this;
   const TypeLong *ot = old->is_long();
   // If new guy is equal to old guy, no widening
   if( _lo == ot->_lo && _hi == ot->_hi )
     return old;
   // If new guy contains old, then we widened
   if( _lo <= ot->_lo && _hi >= ot->_hi ) {
     // New contains old
     // If new guy is already wider than old, no widening
     if( _widen > ot->_widen ) return this;
     // If old guy was a constant, do not bother
     if (ot->_lo == ot->_hi)  return this;
     // Now widen new guy.
     // Check for widening too far
     if (_widen == WidenMax) {
       jlong max = max_jlong;
       jlong min = min_jlong;
       if (limit->isa_long()) {
         max = limit->is_long()->_hi;
         min = limit->is_long()->_lo;
       }
       if (min < _lo && _hi < max) {
         // If neither endpoint is extremal yet, push out the endpoint
         // which is closer to its respective limit.
         if (_lo >= 0 ||                 // easy common case
             (julong)(_lo - min) >= (julong)(max - _hi)) {
           // Try to widen to an unsigned range type of 32/63 bits:
           if (max >= max_juint && _hi < max_juint)
             return make(_lo, max_juint, WidenMax);
           else
             return make(_lo, max, WidenMax);
         } else {
           return make(min, _hi, WidenMax);
         }
       }
       return TypeLong::LONG;
     }
     // Returned widened new guy
     return make(_lo,_hi,_widen+1);
   }
   // If old guy contains new, then we probably widened too far & dropped to
   // bottom.  Return the wider fellow.
   if ( ot->_lo <= _lo && ot->_hi >= _hi )
     return old;
   //  fatal("Long value range is not subset");
   // return this;
   return TypeLong::LONG;
 }
 //------------------------------narrow----------------------------------------
 // Only happens for pessimistic optimizations.
 const Type *TypeLong::narrow( const Type *old ) const {
   if (_lo >= _hi)  return this;   // already narrow enough
   if (old == NULL)  return this;
   const TypeLong* ot = old->isa_long();
   if (ot == NULL)  return this;
   jlong olo = ot->_lo;
   jlong ohi = ot->_hi;
   // If new guy is equal to old guy, no narrowing
   if (_lo == olo && _hi == ohi)  return old;
   // If old guy was maximum range, allow the narrowing
   if (olo == min_jlong && ohi == max_jlong)  return this;
   if (_lo < olo || _hi > ohi)
     return this;                // doesn't narrow; pretty wierd
   // The new type narrows the old type, so look for a "death march".
   // See comments on PhaseTransform::saturate.
   julong nrange = _hi - _lo;
   julong orange = ohi - olo;
   if (nrange < max_julong - 1 && nrange > (orange >> 1) + (SMALLINT*2)) {
     // Use the new type only if the range shrinks a lot.
     // We do not want the optimizer computing 2^31 point by point.
     return old;
   }
   return this;
 }
 //-----------------------------filter------------------------------------------
 const Type *TypeLong::filter( const Type *kills ) const {
   const TypeLong* ft = join(kills)->isa_long();
   if (ft == NULL || ft->empty())
     return Type::TOP;           // Canonical empty value
   if (ft->_widen < this->_widen) {
     // Do not allow the value of kill->_widen to affect the outcome.
     // The widen bits must be allowed to run freely through the graph.
     ft = TypeLong::make(ft->_lo, ft->_hi, this->_widen);
   }
   return ft;
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeLong::eq( const Type *t ) const {
   const TypeLong *r = t->is_long(); // Handy access
   return r->_lo == _lo &&  r->_hi == _hi  && r->_widen == _widen;
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeLong::hash(void) const {
   return (int)(_lo+_hi+_widen+(int)Type::Long);
 }
 //------------------------------is_finite--------------------------------------
 // Has a finite value
 bool TypeLong::is_finite() const {
   return true;
 }
 //------------------------------dump2------------------------------------------
 // Dump TypeLong
 #ifndef PRODUCT
 static const char* longnamenear(jlong x, const char* xname, char* buf, jlong n) {
   if (n > x) {
     if (n >= x + 10000)  return NULL;
     sprintf(buf, "%s+" JLONG_FORMAT, xname, n - x);
   } else if (n < x) {
     if (n <= x - 10000)  return NULL;
     sprintf(buf, "%s-" JLONG_FORMAT, xname, x - n);
   } else {
     return xname;
   }
   return buf;
 }
 static const char* longname(char* buf, jlong n) {
   const char* str;
   if (n == min_jlong)
     return "min";
   else if (n < min_jlong + 10000)
     sprintf(buf, "min+" JLONG_FORMAT, n - min_jlong);
   else if (n == max_jlong)
     return "max";
   else if (n > max_jlong - 10000)
     sprintf(buf, "max-" JLONG_FORMAT, max_jlong - n);
   else if ((str = longnamenear(max_juint, "maxuint", buf, n)) != NULL)
     return str;
   else if ((str = longnamenear(max_jint, "maxint", buf, n)) != NULL)
     return str;
   else if ((str = longnamenear(min_jint, "minint", buf, n)) != NULL)
     return str;
   else
     sprintf(buf, JLONG_FORMAT, n);
   return buf;
 }
 void TypeLong::dump2( Dict &d, uint depth, outputStream *st ) const {
   char buf[80], buf2[80];
   if (_lo == min_jlong && _hi == max_jlong)
     st->print("long");
   else if (is_con())
     st->print("long:%s", longname(buf, get_con()));
   else if (_hi == max_jlong)
     st->print("long:>=%s", longname(buf, _lo));
   else if (_lo == min_jlong)
     st->print("long:<=%s", longname(buf, _hi));
   else
     st->print("long:%s..%s", longname(buf, _lo), longname(buf2, _hi));
   if (_widen != 0 && this != TypeLong::LONG)
     st->print(":%.*s", _widen, "wwww");
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants
 bool TypeLong::singleton(void) const {
   return _lo >= _hi;
 }
 bool TypeLong::empty(void) const {
   return _lo > _hi;
 }
 //=============================================================================
 // Convenience common pre-built types.
 const TypeTuple *TypeTuple::IFBOTH;     // Return both arms of IF as reachable
 const TypeTuple *TypeTuple::IFFALSE;
 const TypeTuple *TypeTuple::IFTRUE;
 const TypeTuple *TypeTuple::IFNEITHER;
 const TypeTuple *TypeTuple::LOOPBODY;
 const TypeTuple *TypeTuple::MEMBAR;
 const TypeTuple *TypeTuple::STORECONDITIONAL;
 const TypeTuple *TypeTuple::START_I2C;
 const TypeTuple *TypeTuple::INT_PAIR;
 const TypeTuple *TypeTuple::LONG_PAIR;
 //------------------------------make-------------------------------------------
 // Make a TypeTuple from the range of a method signature
 const TypeTuple *TypeTuple::make_range(ciSignature* sig) {
   ciType* return_type = sig->return_type();
   uint total_fields = TypeFunc::Parms + return_type->size();
   const Type **field_array = fields(total_fields);
   switch (return_type->basic_type()) {
   case T_LONG:
     field_array[TypeFunc::Parms]   = TypeLong::LONG;
     field_array[TypeFunc::Parms+1] = Type::HALF;
     break;
   case T_DOUBLE:
     field_array[TypeFunc::Parms]   = Type::DOUBLE;
     field_array[TypeFunc::Parms+1] = Type::HALF;
     break;
   case T_OBJECT:
   case T_ARRAY:
   case T_BOOLEAN:
   case T_CHAR:
   case T_FLOAT:
   case T_BYTE:
   case T_SHORT:
   case T_INT:
     field_array[TypeFunc::Parms] = get_const_type(return_type);
     break;
   case T_VOID:
     break;
   default:
     ShouldNotReachHere();
   }
   return (TypeTuple*)(new TypeTuple(total_fields,field_array))->hashcons();
 }
 // Make a TypeTuple from the domain of a method signature
 const TypeTuple *TypeTuple::make_domain(ciInstanceKlass* recv, ciSignature* sig) {
   uint total_fields = TypeFunc::Parms + sig->size();
   uint pos = TypeFunc::Parms;
   const Type **field_array;
   if (recv != NULL) {
     total_fields++;
     field_array = fields(total_fields);
     // Use get_const_type here because it respects UseUniqueSubclasses:
     field_array[pos++] = get_const_type(recv)->join(TypePtr::NOTNULL);
   } else {
     field_array = fields(total_fields);
   }
   int i = 0;
   while (pos < total_fields) {
     ciType* type = sig->type_at(i);
     switch (type->basic_type()) {
     case T_LONG:
       field_array[pos++] = TypeLong::LONG;
       field_array[pos++] = Type::HALF;
       break;
     case T_DOUBLE:
       field_array[pos++] = Type::DOUBLE;
       field_array[pos++] = Type::HALF;
       break;
     case T_OBJECT:
     case T_ARRAY:
     case T_BOOLEAN:
     case T_CHAR:
     case T_FLOAT:
     case T_BYTE:
     case T_SHORT:
     case T_INT:
       field_array[pos++] = get_const_type(type);
       break;
     default:
       ShouldNotReachHere();
     }
     i++;
   }
   return (TypeTuple*)(new TypeTuple(total_fields,field_array))->hashcons();
 }
 const TypeTuple *TypeTuple::make( uint cnt, const Type **fields ) {
   return (TypeTuple*)(new TypeTuple(cnt,fields))->hashcons();
 }
 //------------------------------fields-----------------------------------------
 // Subroutine call type with space allocated for argument types
 const Type **TypeTuple::fields( uint arg_cnt ) {
   const Type **flds = (const Type **)(Compile::current()->type_arena()->Amalloc_4((TypeFunc::Parms+arg_cnt)*sizeof(Type*) ));
   flds[TypeFunc::Control  ] = Type::CONTROL;
   flds[TypeFunc::I_O      ] = Type::ABIO;
   flds[TypeFunc::Memory   ] = Type::MEMORY;
   flds[TypeFunc::FramePtr ] = TypeRawPtr::BOTTOM;
   flds[TypeFunc::ReturnAdr] = Type::RETURN_ADDRESS;
   return flds;
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeTuple::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is Tuple
   switch (t->base()) {          // switch on original type
   case Bottom:                  // Ye Olde Default
     return t;
   default:                      // All else is a mistake
     typerr(t);
   case Tuple: {                 // Meeting 2 signatures?
     const TypeTuple *x = t->is_tuple();
     assert( _cnt == x->_cnt, "" );
     const Type **fields = (const Type **)(Compile::current()->type_arena()->Amalloc_4( _cnt*sizeof(Type*) ));
     for( uint i=0; i<_cnt; i++ )
       fields[i] = field_at(i)->xmeet( x->field_at(i) );
     return TypeTuple::make(_cnt,fields);
   }
   case Top:
     break;
   }
   return this;                  // Return the double constant
 }
 //------------------------------xdual------------------------------------------
 // Dual: compute field-by-field dual
 const Type *TypeTuple::xdual() const {
   const Type **fields = (const Type **)(Compile::current()->type_arena()->Amalloc_4( _cnt*sizeof(Type*) ));
   for( uint i=0; i<_cnt; i++ )
     fields[i] = _fields[i]->dual();
   return new TypeTuple(_cnt,fields);
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeTuple::eq( const Type *t ) const {
   const TypeTuple *s = (const TypeTuple *)t;
   if (_cnt != s->_cnt)  return false;  // Unequal field counts
   for (uint i = 0; i < _cnt; i++)
     if (field_at(i) != s->field_at(i)) // POINTER COMPARE!  NO RECURSION!
       return false;             // Missed
   return true;
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeTuple::hash(void) const {
   intptr_t sum = _cnt;
   for( uint i=0; i<_cnt; i++ )
     sum += (intptr_t)_fields[i];     // Hash on pointers directly
   return sum;
 }
 //------------------------------dump2------------------------------------------
 // Dump signature Type
 #ifndef PRODUCT
 void TypeTuple::dump2( Dict &d, uint depth, outputStream *st ) const {
   st->print("{");
   if( !depth || d[this] ) {     // Check for recursive print
     st->print("...}");
     return;
   }
   d.Insert((void*)this, (void*)this);   // Stop recursion
   if( _cnt ) {
     uint i;
     for( i=0; i<_cnt-1; i++ ) {
       st->print("%d:", i);
       _fields[i]->dump2(d, depth-1, st);
       st->print(", ");
     }
     st->print("%d:", i);
     _fields[i]->dump2(d, depth-1, st);
   }
   st->print("}");
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants (Ldi nodes).  Singletons are integer, float or double constants
 // or a single symbol.
 bool TypeTuple::singleton(void) const {
   return false;                 // Never a singleton
 }
 bool TypeTuple::empty(void) const {
   for( uint i=0; i<_cnt; i++ ) {
     if (_fields[i]->empty())  return true;
   }
   return false;
 }
 //=============================================================================
 // Convenience common pre-built types.
 inline const TypeInt* normalize_array_size(const TypeInt* size) {
   // Certain normalizations keep us sane when comparing types.
   // We do not want arrayOop variables to differ only by the wideness
   // of their index types.  Pick minimum wideness, since that is the
   // forced wideness of small ranges anyway.
   if (size->_widen != Type::WidenMin)
     return TypeInt::make(size->_lo, size->_hi, Type::WidenMin);
   else
     return size;
 }
 //------------------------------make-------------------------------------------
 const TypeAry* TypeAry::make(const Type* elem, const TypeInt* size, bool stable) {
   if (UseCompressedOops && elem->isa_oopptr()) {
     elem = elem->make_narrowoop();
   }
   size = normalize_array_size(size);
   return (TypeAry*)(new TypeAry(elem,size,stable))->hashcons();
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeAry::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is Ary
   switch (t->base()) {          // switch on original type
   case Bottom:                  // Ye Olde Default
     return t;
   default:                      // All else is a mistake
     typerr(t);
   case Array: {                 // Meeting 2 arrays?
     const TypeAry *a = t->is_ary();
     return TypeAry::make(_elem->meet(a->_elem),
                          _size->xmeet(a->_size)->is_int(),
                          _stable & a->_stable);
   }
   case Top:
     break;
   }
   return this;                  // Return the double constant
 }
 //------------------------------xdual------------------------------------------
 // Dual: compute field-by-field dual
 const Type *TypeAry::xdual() const {
   const TypeInt* size_dual = _size->dual()->is_int();
   size_dual = normalize_array_size(size_dual);
   return new TypeAry(_elem->dual(), size_dual, !_stable);
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeAry::eq( const Type *t ) const {
   const TypeAry *a = (const TypeAry*)t;
   return _elem == a->_elem &&
     _stable == a->_stable &&
     _size == a->_size;
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeAry::hash(void) const {
   return (intptr_t)_elem + (intptr_t)_size + (_stable ? 43 : 0);
 }
 //----------------------interface_vs_oop---------------------------------------
 #ifdef ASSERT
 bool TypeAry::interface_vs_oop(const Type *t) const {
   const TypeAry* t_ary = t->is_ary();
   if (t_ary) {
     return _elem->interface_vs_oop(t_ary->_elem);
   }
   return false;
 }
 #endif
 //------------------------------dump2------------------------------------------
 #ifndef PRODUCT
 void TypeAry::dump2( Dict &d, uint depth, outputStream *st ) const {
   if (_stable)  st->print("stable:");
   _elem->dump2(d, depth, st);
   st->print("[");
   _size->dump2(d, depth, st);
   st->print("]");
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants (Ldi nodes).  Singletons are integer, float or double constants
 // or a single symbol.
 bool TypeAry::singleton(void) const {
   return false;                 // Never a singleton
 }
 bool TypeAry::empty(void) const {
   return _elem->empty() || _size->empty();
 }
 //--------------------------ary_must_be_exact----------------------------------
 bool TypeAry::ary_must_be_exact() const {
   if (!UseExactTypes)       return false;
   // This logic looks at the element type of an array, and returns true
   // if the element type is either a primitive or a final instance class.
   // In such cases, an array built on this ary must have no subclasses.
   if (_elem == BOTTOM)      return false;  // general array not exact
   if (_elem == TOP   )      return false;  // inverted general array not exact
   const TypeOopPtr*  toop = NULL;
   if (UseCompressedOops && _elem->isa_narrowoop()) {
     toop = _elem->make_ptr()->isa_oopptr();
   } else {
     toop = _elem->isa_oopptr();
   }
   if (!toop)                return true;   // a primitive type, like int
   ciKlass* tklass = toop->klass();
   if (tklass == NULL)       return false;  // unloaded class
   if (!tklass->is_loaded()) return false;  // unloaded class
   const TypeInstPtr* tinst;
   if (_elem->isa_narrowoop())
     tinst = _elem->make_ptr()->isa_instptr();
   else
     tinst = _elem->isa_instptr();
   if (tinst)
     return tklass->as_instance_klass()->is_final();
   const TypeAryPtr*  tap;
   if (_elem->isa_narrowoop())
     tap = _elem->make_ptr()->isa_aryptr();
   else
     tap = _elem->isa_aryptr();
   if (tap)
     return tap->ary()->ary_must_be_exact();
   return false;
 }
 //==============================TypeVect=======================================
 // Convenience common pre-built types.
 const TypeVect *TypeVect::VECTS = NULL; //  32-bit vectors
 const TypeVect *TypeVect::VECTD = NULL; //  64-bit vectors
 const TypeVect *TypeVect::VECTX = NULL; // 128-bit vectors
 const TypeVect *TypeVect::VECTY = NULL; // 256-bit vectors
 //------------------------------make-------------------------------------------
 const TypeVect* TypeVect::make(const Type *elem, uint length) {
   BasicType elem_bt = elem->array_element_basic_type();
   assert(is_java_primitive(elem_bt), "only primitive types in vector");
   assert(length > 1 && is_power_of_2(length), "vector length is power of 2");
   assert(Matcher::vector_size_supported(elem_bt, length), "length in range");
   int size = length * type2aelembytes(elem_bt);
   switch (Matcher::vector_ideal_reg(size)) {
   case Op_VecS:
     return (TypeVect*)(new TypeVectS(elem, length))->hashcons();
   case Op_VecD:
   case Op_RegD:
     return (TypeVect*)(new TypeVectD(elem, length))->hashcons();
   case Op_VecX:
     return (TypeVect*)(new TypeVectX(elem, length))->hashcons();
   case Op_VecY:
     return (TypeVect*)(new TypeVectY(elem, length))->hashcons();
   }
  ShouldNotReachHere();
   return NULL;
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeVect::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is Vector
   switch (t->base()) {          // switch on original type
   case Bottom:                  // Ye Olde Default
     return t;
   default:                      // All else is a mistake
     typerr(t);
   case VectorS:
   case VectorD:
   case VectorX:
   case VectorY: {                // Meeting 2 vectors?
     const TypeVect* v = t->is_vect();
     assert(  base() == v->base(), "");
     assert(length() == v->length(), "");
     assert(element_basic_type() == v->element_basic_type(), "");
     return TypeVect::make(_elem->xmeet(v->_elem), _length);
   }
   case Top:
     break;
   }
   return this;
 }
 //------------------------------xdual------------------------------------------
 // Dual: compute field-by-field dual
 const Type *TypeVect::xdual() const {
   return new TypeVect(base(), _elem->dual(), _length);
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeVect::eq(const Type *t) const {
   const TypeVect *v = t->is_vect();
   return (_elem == v->_elem) && (_length == v->_length);
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeVect::hash(void) const {
   return (intptr_t)_elem + (intptr_t)_length;
 }
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants (Ldi nodes).  Vector is singleton if all elements are the same
 // constant value (when vector is created with Replicate code).
 bool TypeVect::singleton(void) const {
 // There is no Con node for vectors yet.
 //  return _elem->singleton();
   return false;
 }
 bool TypeVect::empty(void) const {
   return _elem->empty();
 }
 //------------------------------dump2------------------------------------------
 #ifndef PRODUCT
 void TypeVect::dump2(Dict &d, uint depth, outputStream *st) const {
   switch (base()) {
   case VectorS:
     st->print("vectors["); break;
   case VectorD:
     st->print("vectord["); break;
   case VectorX:
     st->print("vectorx["); break;
   case VectorY:
     st->print("vectory["); break;
   default:
     ShouldNotReachHere();
   }
   st->print("%d]:{", _length);
   _elem->dump2(d, depth, st);
   st->print("}");
 }
 #endif
 //=============================================================================
 // Convenience common pre-built types.
 const TypePtr *TypePtr::NULL_PTR;
 const TypePtr *TypePtr::NOTNULL;
 const TypePtr *TypePtr::BOTTOM;
 //------------------------------meet-------------------------------------------
 // Meet over the PTR enum
 const TypePtr::PTR TypePtr::ptr_meet[TypePtr::lastPTR][TypePtr::lastPTR] = {
   //              TopPTR,    AnyNull,   Constant, Null,   NotNull, BotPTR,
   { /* Top     */ TopPTR,    AnyNull,   Constant, Null,   NotNull, BotPTR,},
   { /* AnyNull */ AnyNull,   AnyNull,   Constant, BotPTR, NotNull, BotPTR,},
   { /* Constant*/ Constant,  Constant,  Constant, BotPTR, NotNull, BotPTR,},
   { /* Null    */ Null,      BotPTR,    BotPTR,   Null,   BotPTR,  BotPTR,},
   { /* NotNull */ NotNull,   NotNull,   NotNull,  BotPTR, NotNull, BotPTR,},
   { /* BotPTR  */ BotPTR,    BotPTR,    BotPTR,   BotPTR, BotPTR,  BotPTR,}
 };
 //------------------------------make-------------------------------------------
 const TypePtr *TypePtr::make( TYPES t, enum PTR ptr, int offset ) {
   return (TypePtr*)(new TypePtr(t,ptr,offset))->hashcons();
 }
 //------------------------------cast_to_ptr_type-------------------------------
 const Type *TypePtr::cast_to_ptr_type(PTR ptr) const {
   assert(_base == AnyPtr, "subclass must override cast_to_ptr_type");
   if( ptr == _ptr ) return this;
   return make(_base, ptr, _offset);
 }
 //------------------------------get_con----------------------------------------
 intptr_t TypePtr::get_con() const {
   assert( _ptr == Null, "" );
   return _offset;
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypePtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is AnyPtr
   switch (t->base()) {          // switch on original type
   case Int:                     // Mixing ints & oops happens when javac
   case Long:                    // reuses local variables
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
   case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
     return this;
   case AnyPtr: {                // Meeting to AnyPtrs
     const TypePtr *tp = t->is_ptr();
     return make( AnyPtr, meet_ptr(tp->ptr()), meet_offset(tp->offset()) );
   }
   case RawPtr:                  // For these, flip the call around to cut down
   case OopPtr:
   case InstPtr:                 // on the cases I have to handle.
   case AryPtr:
   case MetadataPtr:
   case KlassPtr:
     return t->xmeet(this);      // Call in reverse direction
   default:                      // All else is a mistake
     typerr(t);
   }
   return this;
 }
 //------------------------------meet_offset------------------------------------
 int TypePtr::meet_offset( int offset ) const {
   // Either is 'TOP' offset?  Return the other offset!
   if( _offset == OffsetTop ) return offset;
   if( offset == OffsetTop ) return _offset;
   // If either is different, return 'BOTTOM' offset
   if( _offset != offset ) return OffsetBot;
   return _offset;
 }
 //------------------------------dual_offset------------------------------------
 int TypePtr::dual_offset( ) const {
   if( _offset == OffsetTop ) return OffsetBot;// Map 'TOP' into 'BOTTOM'
   if( _offset == OffsetBot ) return OffsetTop;// Map 'BOTTOM' into 'TOP'
   return _offset;               // Map everything else into self
 }
 //------------------------------xdual------------------------------------------
 // Dual: compute field-by-field dual
 const TypePtr::PTR TypePtr::ptr_dual[TypePtr::lastPTR] = {
   BotPTR, NotNull, Constant, Null, AnyNull, TopPTR
 };
 const Type *TypePtr::xdual() const {
   return new TypePtr( AnyPtr, dual_ptr(), dual_offset() );
 }
 //------------------------------xadd_offset------------------------------------
 int TypePtr::xadd_offset( intptr_t offset ) const {
   // Adding to 'TOP' offset?  Return 'TOP'!
   if( _offset == OffsetTop || offset == OffsetTop ) return OffsetTop;
   // Adding to 'BOTTOM' offset?  Return 'BOTTOM'!
   if( _offset == OffsetBot || offset == OffsetBot ) return OffsetBot;
   // Addition overflows or "accidentally" equals to OffsetTop? Return 'BOTTOM'!
   offset += (intptr_t)_offset;
   if (offset != (int)offset || offset == OffsetTop) return OffsetBot;
   // assert( _offset >= 0 && _offset+offset >= 0, "" );
   // It is possible to construct a negative offset during PhaseCCP
   return (int)offset;        // Sum valid offsets
 }
 //------------------------------add_offset-------------------------------------
 const TypePtr *TypePtr::add_offset( intptr_t offset ) const {
   return make( AnyPtr, _ptr, xadd_offset(offset) );
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypePtr::eq( const Type *t ) const {
   const TypePtr *a = (const TypePtr*)t;
   return _ptr == a->ptr() && _offset == a->offset();
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypePtr::hash(void) const {
   return _ptr + _offset;
 }
 //------------------------------dump2------------------------------------------
 const char *const TypePtr::ptr_msg[TypePtr::lastPTR] = {
   "TopPTR","AnyNull","Constant","NULL","NotNull","BotPTR"
 };
 #ifndef PRODUCT
 void TypePtr::dump2( Dict &d, uint depth, outputStream *st ) const {
   if( _ptr == Null ) st->print("NULL");
   else st->print("%s *", ptr_msg[_ptr]);
   if( _offset == OffsetTop ) st->print("+top");
   else if( _offset == OffsetBot ) st->print("+bot");
   else if( _offset ) st->print("+%d", _offset);
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants
 bool TypePtr::singleton(void) const {
   // TopPTR, Null, AnyNull, Constant are all singletons
   return (_offset != OffsetBot) && !below_centerline(_ptr);
 }
 bool TypePtr::empty(void) const {
   return (_offset == OffsetTop) || above_centerline(_ptr);
 }
 //=============================================================================
 // Convenience common pre-built types.
 const TypeRawPtr *TypeRawPtr::BOTTOM;
 const TypeRawPtr *TypeRawPtr::NOTNULL;
 //------------------------------make-------------------------------------------
 const TypeRawPtr *TypeRawPtr::make( enum PTR ptr ) {
   assert( ptr != Constant, "what is the constant?" );
   assert( ptr != Null, "Use TypePtr for NULL" );
   return (TypeRawPtr*)(new TypeRawPtr(ptr,0))->hashcons();
 }
 const TypeRawPtr *TypeRawPtr::make( address bits ) {
   assert( bits, "Use TypePtr for NULL" );
   return (TypeRawPtr*)(new TypeRawPtr(Constant,bits))->hashcons();
 }
 //------------------------------cast_to_ptr_type-------------------------------
 const Type *TypeRawPtr::cast_to_ptr_type(PTR ptr) const {
   assert( ptr != Constant, "what is the constant?" );
   assert( ptr != Null, "Use TypePtr for NULL" );
   assert( _bits==0, "Why cast a constant address?");
   if( ptr == _ptr ) return this;
   return make(ptr);
 }
 //------------------------------get_con----------------------------------------
 intptr_t TypeRawPtr::get_con() const {
   assert( _ptr == Null || _ptr == Constant, "" );
   return (intptr_t)_bits;
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeRawPtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is RawPtr
   switch( t->base() ) {         // switch on original type
   case Bottom:                  // Ye Olde Default
     return t;
   case Top:
     return this;
   case AnyPtr:                  // Meeting to AnyPtrs
     break;
   case RawPtr: {                // might be top, bot, any/not or constant
     enum PTR tptr = t->is_ptr()->ptr();
     enum PTR ptr = meet_ptr( tptr );
     if( ptr == Constant ) {     // Cannot be equal constants, so...
       if( tptr == Constant && _ptr != Constant)  return t;
       if( _ptr == Constant && tptr != Constant)  return this;
       ptr = NotNull;            // Fall down in lattice
     }
     return make( ptr );
   }
   case OopPtr:
   case InstPtr:
   case AryPtr:
   case MetadataPtr:
   case KlassPtr:
     return TypePtr::BOTTOM;     // Oop meet raw is not well defined
   default:                      // All else is a mistake
     typerr(t);
   }
   // Found an AnyPtr type vs self-RawPtr type
   const TypePtr *tp = t->is_ptr();
   switch (tp->ptr()) {
   case TypePtr::TopPTR:  return this;
   case TypePtr::BotPTR:  return t;
   case TypePtr::Null:
     if( _ptr == TypePtr::TopPTR ) return t;
     return TypeRawPtr::BOTTOM;
   case TypePtr::NotNull: return TypePtr::make( AnyPtr, meet_ptr(TypePtr::NotNull), tp->meet_offset(0) );
   case TypePtr::AnyNull:
     if( _ptr == TypePtr::Constant) return this;
     return make( meet_ptr(TypePtr::AnyNull) );
   default: ShouldNotReachHere();
   }
   return this;
 }
 //------------------------------xdual------------------------------------------
 // Dual: compute field-by-field dual
 const Type *TypeRawPtr::xdual() const {
   return new TypeRawPtr( dual_ptr(), _bits );
 }
 //------------------------------add_offset-------------------------------------
 const TypePtr *TypeRawPtr::add_offset( intptr_t offset ) const {
   if( offset == OffsetTop ) return BOTTOM; // Undefined offset-> undefined pointer
   if( offset == OffsetBot ) return BOTTOM; // Unknown offset-> unknown pointer
   if( offset == 0 ) return this; // No change
   switch (_ptr) {
   case TypePtr::TopPTR:
   case TypePtr::BotPTR:
   case TypePtr::NotNull:
     return this;
   case TypePtr::Null:
   case TypePtr::Constant: {
     address bits = _bits+offset;
     if ( bits == 0 ) return TypePtr::NULL_PTR;
     return make( bits );
   }
   default:  ShouldNotReachHere();
   }
   return NULL;                  // Lint noise
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeRawPtr::eq( const Type *t ) const {
   const TypeRawPtr *a = (const TypeRawPtr*)t;
   return _bits == a->_bits && TypePtr::eq(t);
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeRawPtr::hash(void) const {
   return (intptr_t)_bits + TypePtr::hash();
 }
 //------------------------------dump2------------------------------------------
 #ifndef PRODUCT
 void TypeRawPtr::dump2( Dict &d, uint depth, outputStream *st ) const {
   if( _ptr == Constant )
     st->print(INTPTR_FORMAT, _bits);
   else
     st->print("rawptr:%s", ptr_msg[_ptr]);
 }
 #endif
 //=============================================================================
 // Convenience common pre-built type.
 const TypeOopPtr *TypeOopPtr::BOTTOM;
 //------------------------------TypeOopPtr-------------------------------------
 TypeOopPtr::TypeOopPtr( TYPES t, PTR ptr, ciKlass* k, bool xk, ciObject* o, int offset, int instance_id )
   : TypePtr(t, ptr, offset),
     _const_oop(o), _klass(k),
     _klass_is_exact(xk),
     _is_ptr_to_narrowoop(false),
     _is_ptr_to_narrowklass(false),
     _is_ptr_to_boxed_value(false),
     _instance_id(instance_id) {
   if (Compile::current()->eliminate_boxing() && (t == InstPtr) &&
       (offset > 0) && xk && (k != 0) && k->is_instance_klass()) {
     _is_ptr_to_boxed_value = k->as_instance_klass()->is_boxed_value_offset(offset);
   }
 #ifdef _LP64
   if (_offset != 0) {
     if (_offset == oopDesc::klass_offset_in_bytes()) {
       _is_ptr_to_narrowklass = UseCompressedClassPointers;
     } else if (klass() == NULL) {
       // Array with unknown body type
       assert(this->isa_aryptr(), "only arrays without klass");
       _is_ptr_to_narrowoop = UseCompressedOops;
     } else if (this->isa_aryptr()) {
       _is_ptr_to_narrowoop = (UseCompressedOops && klass()->is_obj_array_klass() &&
                              _offset != arrayOopDesc::length_offset_in_bytes());
     } else if (klass()->is_instance_klass()) {
       ciInstanceKlass* ik = klass()->as_instance_klass();
       ciField* field = NULL;
       if (this->isa_klassptr()) {
         // Perm objects don't use compressed references
       } else if (_offset == OffsetBot || _offset == OffsetTop) {
         // unsafe access
         _is_ptr_to_narrowoop = UseCompressedOops;
       } else { // exclude unsafe ops
         assert(this->isa_instptr(), "must be an instance ptr.");
         if (klass() == ciEnv::current()->Class_klass() &&
             (_offset == java_lang_Class::klass_offset_in_bytes() ||
              _offset == java_lang_Class::array_klass_offset_in_bytes())) {
           // Special hidden fields from the Class.
           assert(this->isa_instptr(), "must be an instance ptr.");
           _is_ptr_to_narrowoop = false;
         } else if (klass() == ciEnv::current()->Class_klass() &&
                    _offset >= InstanceMirrorKlass::offset_of_static_fields()) {
           // Static fields
           assert(o != NULL, "must be constant");
           ciInstanceKlass* k = o->as_instance()->java_lang_Class_klass()->as_instance_klass();
           ciField* field = k->get_field_by_offset(_offset, true);
           assert(field != NULL, "missing field");
           BasicType basic_elem_type = field->layout_type();
           _is_ptr_to_narrowoop = UseCompressedOops && (basic_elem_type == T_OBJECT ||
                                                        basic_elem_type == T_ARRAY);
         } else {
           // Instance fields which contains a compressed oop references.
           field = ik->get_field_by_offset(_offset, false);
           if (field != NULL) {
             BasicType basic_elem_type = field->layout_type();
             _is_ptr_to_narrowoop = UseCompressedOops && (basic_elem_type == T_OBJECT ||
                                                          basic_elem_type == T_ARRAY);
           } else if (klass()->equals(ciEnv::current()->Object_klass())) {
             // Compile::find_alias_type() cast exactness on all types to verify
             // that it does not affect alias type.
             _is_ptr_to_narrowoop = UseCompressedOops;
           } else {
             // Type for the copy start in LibraryCallKit::inline_native_clone().
             _is_ptr_to_narrowoop = UseCompressedOops;
           }
         }
       }
     }
   }
 #endif
 }
 //------------------------------make-------------------------------------------
 const TypeOopPtr *TypeOopPtr::make(PTR ptr,
                                    int offset, int instance_id) {
   assert(ptr != Constant, "no constant generic pointers");
   ciKlass*  k = Compile::current()->env()->Object_klass();
   bool      xk = false;
   ciObject* o = NULL;
   return (TypeOopPtr*)(new TypeOopPtr(OopPtr, ptr, k, xk, o, offset, instance_id))->hashcons();
 }
 //------------------------------cast_to_ptr_type-------------------------------
 const Type *TypeOopPtr::cast_to_ptr_type(PTR ptr) const {
   assert(_base == OopPtr, "subclass must override cast_to_ptr_type");
   if( ptr == _ptr ) return this;
   return make(ptr, _offset, _instance_id);
 }
 //-----------------------------cast_to_instance_id----------------------------
 const TypeOopPtr *TypeOopPtr::cast_to_instance_id(int instance_id) const {
   // There are no instances of a general oop.
   // Return self unchanged.
   return this;
 }
 //-----------------------------cast_to_exactness-------------------------------
 const Type *TypeOopPtr::cast_to_exactness(bool klass_is_exact) const {
   // There is no such thing as an exact general oop.
   // Return self unchanged.
   return this;
 }
 //------------------------------as_klass_type----------------------------------
 // Return the klass type corresponding to this instance or array type.
 // It is the type that is loaded from an object of this type.
 const TypeKlassPtr* TypeOopPtr::as_klass_type() const {
   ciKlass* k = klass();
   bool    xk = klass_is_exact();
   if (k == NULL)
     return TypeKlassPtr::OBJECT;
   else
     return TypeKlassPtr::make(xk? Constant: NotNull, k, 0);
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeOopPtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is OopPtr
   switch (t->base()) {          // switch on original type
   case Int:                     // Mixing ints & oops happens when javac
   case Long:                    // reuses local variables
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
   case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
     return this;
   default:                      // All else is a mistake
     typerr(t);
   case RawPtr:
   case MetadataPtr:
   case KlassPtr:
     return TypePtr::BOTTOM;     // Oop meet raw is not well defined
   case AnyPtr: {
     // Found an AnyPtr type vs self-OopPtr type
     const TypePtr *tp = t->is_ptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     switch (tp->ptr()) {
     case Null:
       if (ptr == Null)  return TypePtr::make(AnyPtr, ptr, offset);
       // else fall through:
     case TopPTR:
     case AnyNull: {
       int instance_id = meet_instance_id(InstanceTop);
       return make(ptr, offset, instance_id);
     }
     case BotPTR:
     case NotNull:
       return TypePtr::make(AnyPtr, ptr, offset);
     default: typerr(t);
     }
   }
   case OopPtr: {                 // Meeting to other OopPtrs
     const TypeOopPtr *tp = t->is_oopptr();
     int instance_id = meet_instance_id(tp->instance_id());
     return make( meet_ptr(tp->ptr()), meet_offset(tp->offset()), instance_id );
   }
   case InstPtr:                  // For these, flip the call around to cut down
   case AryPtr:
     return t->xmeet(this);      // Call in reverse direction
   } // End of switch
   return this;                  // Return the double constant
 }
 //------------------------------xdual------------------------------------------
 // Dual of a pure heap pointer.  No relevant klass or oop information.
 const Type *TypeOopPtr::xdual() const {
   assert(klass() == Compile::current()->env()->Object_klass(), "no klasses here");
   assert(const_oop() == NULL,             "no constants here");
   return new TypeOopPtr(_base, dual_ptr(), klass(), klass_is_exact(), const_oop(), dual_offset(), dual_instance_id()  );
 }
 //--------------------------make_from_klass_common-----------------------------
 // Computes the element-type given a klass.
 const TypeOopPtr* TypeOopPtr::make_from_klass_common(ciKlass *klass, bool klass_change, bool try_for_exact) {
   if (klass->is_instance_klass()) {
     Compile* C = Compile::current();
     Dependencies* deps = C->dependencies();
     assert((deps != NULL) == (C->method() != NULL && C->method()->code_size() > 0), "sanity");
     // Element is an instance
     bool klass_is_exact = false;
     if (klass->is_loaded()) {
       // Try to set klass_is_exact.
       ciInstanceKlass* ik = klass->as_instance_klass();
       klass_is_exact = ik->is_final();
       if (!klass_is_exact && klass_change
           && deps != NULL && UseUniqueSubclasses) {
         ciInstanceKlass* sub = ik->unique_concrete_subklass();
         if (sub != NULL) {
           deps->assert_abstract_with_unique_concrete_subtype(ik, sub);
           klass = ik = sub;
           klass_is_exact = sub->is_final();
         }
       }
       if (!klass_is_exact && try_for_exact
           && deps != NULL && UseExactTypes) {
         if (!ik->is_interface() && !ik->has_subklass()) {
           // Add a dependence; if concrete subclass added we need to recompile
           deps->assert_leaf_type(ik);
           klass_is_exact = true;
         }
       }
     }
     return TypeInstPtr::make(TypePtr::BotPTR, klass, klass_is_exact, NULL, 0);
   } else if (klass->is_obj_array_klass()) {
     // Element is an object array. Recursively call ourself.
     const TypeOopPtr *etype = TypeOopPtr::make_from_klass_common(klass->as_obj_array_klass()->element_klass(), false, try_for_exact);
     bool xk = etype->klass_is_exact();
     const TypeAry* arr0 = TypeAry::make(etype, TypeInt::POS);
     // We used to pass NotNull in here, asserting that the sub-arrays
     // are all not-null.  This is not true in generally, as code can
     // slam NULLs down in the subarrays.
     const TypeAryPtr* arr = TypeAryPtr::make(TypePtr::BotPTR, arr0, klass, xk, 0);
     return arr;
   } else if (klass->is_type_array_klass()) {
     // Element is an typeArray
     const Type* etype = get_const_basic_type(klass->as_type_array_klass()->element_type());
     const TypeAry* arr0 = TypeAry::make(etype, TypeInt::POS);
     // We used to pass NotNull in here, asserting that the array pointer
     // is not-null. That was not true in general.
     const TypeAryPtr* arr = TypeAryPtr::make(TypePtr::BotPTR, arr0, klass, true, 0);
     return arr;
   } else {
     ShouldNotReachHere();
     return NULL;
   }
 }
 //------------------------------make_from_constant-----------------------------
 // Make a java pointer from an oop constant
 const TypeOopPtr* TypeOopPtr::make_from_constant(ciObject* o,
                                                  bool require_constant,
                                                  bool is_autobox_cache) {
   assert(!o->is_null_object(), "null object not yet handled here.");
   ciKlass* klass = o->klass();
   if (klass->is_instance_klass()) {
     // Element is an instance
     if (require_constant) {
       if (!o->can_be_constant())  return NULL;
     } else if (!o->should_be_constant()) {
       return TypeInstPtr::make(TypePtr::NotNull, klass, true, NULL, 0);
     }
     return TypeInstPtr::make(o);
   } else if (klass->is_obj_array_klass()) {
     // Element is an object array. Recursively call ourself.
     const TypeOopPtr *etype =
       TypeOopPtr::make_from_klass_raw(klass->as_obj_array_klass()->element_klass());
     if (is_autobox_cache) {
       // The pointers in the autobox arrays are always non-null.
       etype = etype->cast_to_ptr_type(TypePtr::NotNull)->is_oopptr();
     }
     const TypeAry* arr0 = TypeAry::make(etype, TypeInt::make(o->as_array()->length()));
     // We used to pass NotNull in here, asserting that the sub-arrays
     // are all not-null.  This is not true in generally, as code can
     // slam NULLs down in the subarrays.
     if (require_constant) {
       if (!o->can_be_constant())  return NULL;
     } else if (!o->should_be_constant()) {
       return TypeAryPtr::make(TypePtr::NotNull, arr0, klass, true, 0);
     }
     const TypeAryPtr* arr = TypeAryPtr::make(TypePtr::Constant, o, arr0, klass, true, 0, InstanceBot, is_autobox_cache);
     return arr;
   } else if (klass->is_type_array_klass()) {
     // Element is an typeArray
     const Type* etype =
       (Type*)get_const_basic_type(klass->as_type_array_klass()->element_type());
     const TypeAry* arr0 = TypeAry::make(etype, TypeInt::make(o->as_array()->length()));
     // We used to pass NotNull in here, asserting that the array pointer
     // is not-null. That was not true in general.
     if (require_constant) {
       if (!o->can_be_constant())  return NULL;
     } else if (!o->should_be_constant()) {
       return TypeAryPtr::make(TypePtr::NotNull, arr0, klass, true, 0);
     }
     const TypeAryPtr* arr = TypeAryPtr::make(TypePtr::Constant, o, arr0, klass, true, 0);
     return arr;
   }
   fatal("unhandled object type");
   return NULL;
 }
 //------------------------------get_con----------------------------------------
 intptr_t TypeOopPtr::get_con() const {
   assert( _ptr == Null || _ptr == Constant, "" );
   assert( _offset >= 0, "" );
   if (_offset != 0) {
     // After being ported to the compiler interface, the compiler no longer
     // directly manipulates the addresses of oops.  Rather, it only has a pointer
     // to a handle at compile time.  This handle is embedded in the generated
     // code and dereferenced at the time the nmethod is made.  Until that time,
     // it is not reasonable to do arithmetic with the addresses of oops (we don't
     // have access to the addresses!).  This does not seem to currently happen,
     // but this assertion here is to help prevent its occurence.
     tty->print_cr("Found oop constant with non-zero offset");
     ShouldNotReachHere();
   }
   return (intptr_t)const_oop()->constant_encoding();
 }
 //-----------------------------filter------------------------------------------
 // Do not allow interface-vs.-noninterface joins to collapse to top.
 const Type *TypeOopPtr::filter( const Type *kills ) const {
   const Type* ft = join(kills);
   const TypeInstPtr* ftip = ft->isa_instptr();
   const TypeInstPtr* ktip = kills->isa_instptr();
   const TypeKlassPtr* ftkp = ft->isa_klassptr();
   const TypeKlassPtr* ktkp = kills->isa_klassptr();
   if (ft->empty()) {
     // Check for evil case of 'this' being a class and 'kills' expecting an
     // interface.  This can happen because the bytecodes do not contain
     // enough type info to distinguish a Java-level interface variable
     // from a Java-level object variable.  If we meet 2 classes which
     // both implement interface I, but their meet is at 'j/l/O' which
     // doesn't implement I, we have no way to tell if the result should
     // be 'I' or 'j/l/O'.  Thus we'll pick 'j/l/O'.  If this then flows
     // into a Phi which "knows" it's an Interface type we'll have to
     // uplift the type.
     if (!empty() && ktip != NULL && ktip->is_loaded() && ktip->klass()->is_interface())
       return kills;             // Uplift to interface
     if (!empty() && ktkp != NULL && ktkp->klass()->is_loaded() && ktkp->klass()->is_interface())
       return kills;             // Uplift to interface
     return Type::TOP;           // Canonical empty value
   }
   // If we have an interface-typed Phi or cast and we narrow to a class type,
   // the join should report back the class.  However, if we have a J/L/Object
   // class-typed Phi and an interface flows in, it's possible that the meet &
   // join report an interface back out.  This isn't possible but happens
   // because the type system doesn't interact well with interfaces.
   if (ftip != NULL && ktip != NULL &&
       ftip->is_loaded() &&  ftip->klass()->is_interface() &&
       ktip->is_loaded() && !ktip->klass()->is_interface()) {
     // Happens in a CTW of rt.jar, 320-341, no extra flags
     assert(!ftip->klass_is_exact(), "interface could not be exact");
     return ktip->cast_to_ptr_type(ftip->ptr());
   }
   // Interface klass type could be exact in opposite to interface type,
   // return it here instead of incorrect Constant ptr J/L/Object (6894807).
   if (ftkp != NULL && ktkp != NULL &&
       ftkp->is_loaded() &&  ftkp->klass()->is_interface() &&
       !ftkp->klass_is_exact() && // Keep exact interface klass
       ktkp->is_loaded() && !ktkp->klass()->is_interface()) {
     return ktkp->cast_to_ptr_type(ftkp->ptr());
   }
   return ft;
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeOopPtr::eq( const Type *t ) const {
   const TypeOopPtr *a = (const TypeOopPtr*)t;
   if (_klass_is_exact != a->_klass_is_exact ||
       _instance_id != a->_instance_id)  return false;
   ciObject* one = const_oop();
   ciObject* two = a->const_oop();
   if (one == NULL || two == NULL) {
     return (one == two) && TypePtr::eq(t);
   } else {
     return one->equals(two) && TypePtr::eq(t);
   }
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeOopPtr::hash(void) const {
   return
     (const_oop() ? const_oop()->hash() : 0) +
     _klass_is_exact +
     _instance_id +
     TypePtr::hash();
 }
 //------------------------------dump2------------------------------------------
 #ifndef PRODUCT
 void TypeOopPtr::dump2( Dict &d, uint depth, outputStream *st ) const {
   st->print("oopptr:%s", ptr_msg[_ptr]);
   if( _klass_is_exact ) st->print(":exact");
   if( const_oop() ) st->print(INTPTR_FORMAT, const_oop());
   switch( _offset ) {
   case OffsetTop: st->print("+top"); break;
   case OffsetBot: st->print("+any"); break;
   case         0: break;
   default:        st->print("+%d",_offset); break;
   }
   if (_instance_id == InstanceTop)
     st->print(",iid=top");
   else if (_instance_id != InstanceBot)
     st->print(",iid=%d",_instance_id);
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants
 bool TypeOopPtr::singleton(void) const {
   // detune optimizer to not generate constant oop + constant offset as a constant!
   // TopPTR, Null, AnyNull, Constant are all singletons
   return (_offset == 0) && !below_centerline(_ptr);
 }
 //------------------------------add_offset-------------------------------------
 const TypePtr *TypeOopPtr::add_offset( intptr_t offset ) const {
   return make( _ptr, xadd_offset(offset), _instance_id);
 }
 //------------------------------meet_instance_id--------------------------------
 int TypeOopPtr::meet_instance_id( int instance_id ) const {
   // Either is 'TOP' instance?  Return the other instance!
   if( _instance_id == InstanceTop ) return  instance_id;
   if(  instance_id == InstanceTop ) return _instance_id;
   // If either is different, return 'BOTTOM' instance
   if( _instance_id != instance_id ) return InstanceBot;
   return _instance_id;
 }
 //------------------------------dual_instance_id--------------------------------
 int TypeOopPtr::dual_instance_id( ) const {
   if( _instance_id == InstanceTop ) return InstanceBot; // Map TOP into BOTTOM
   if( _instance_id == InstanceBot ) return InstanceTop; // Map BOTTOM into TOP
   return _instance_id;              // Map everything else into self
 }
 //=============================================================================
 // Convenience common pre-built types.
 const TypeInstPtr *TypeInstPtr::NOTNULL;
 const TypeInstPtr *TypeInstPtr::BOTTOM;
 const TypeInstPtr *TypeInstPtr::MIRROR;
 const TypeInstPtr *TypeInstPtr::MARK;
 const TypeInstPtr *TypeInstPtr::KLASS;
 //------------------------------TypeInstPtr-------------------------------------
 TypeInstPtr::TypeInstPtr(PTR ptr, ciKlass* k, bool xk, ciObject* o, int off, int instance_id)
  : TypeOopPtr(InstPtr, ptr, k, xk, o, off, instance_id), _name(k->name()) {
    assert(k != NULL &&
           (k->is_loaded() || o == NULL),
           "cannot have constants with non-loaded klass");
 };
 //------------------------------make-------------------------------------------
 const TypeInstPtr *TypeInstPtr::make(PTR ptr,
                                      ciKlass* k,
                                      bool xk,
                                      ciObject* o,
                                      int offset,
                                      int instance_id) {
   assert( !k->is_loaded() || k->is_instance_klass(), "Must be for instance");
   // Either const_oop() is NULL or else ptr is Constant
   assert( (!o && ptr != Constant) || (o && ptr == Constant),
           "constant pointers must have a value supplied" );
   // Ptr is never Null
   assert( ptr != Null, "NULL pointers are not typed" );
   assert(instance_id <= 0 || xk || !UseExactTypes, "instances are always exactly typed");
   if (!UseExactTypes)  xk = false;
   if (ptr == Constant) {
     // Note:  This case includes meta-object constants, such as methods.
     xk = true;
   } else if (k->is_loaded()) {
     ciInstanceKlass* ik = k->as_instance_klass();
     if (!xk && ik->is_final())     xk = true;   // no inexact final klass
     if (xk && ik->is_interface())  xk = false;  // no exact interface
   }
   // Now hash this baby
   TypeInstPtr *result =
     (TypeInstPtr*)(new TypeInstPtr(ptr, k, xk, o ,offset, instance_id))->hashcons();
   return result;
 }
 /**
  *  Create constant type for a constant boxed value
  */
 const Type* TypeInstPtr::get_const_boxed_value() const {
   assert(is_ptr_to_boxed_value(), "should be called only for boxed value");
   assert((const_oop() != NULL), "should be called only for constant object");
   ciConstant constant = const_oop()->as_instance()->field_value_by_offset(offset());
   BasicType bt = constant.basic_type();
   switch (bt) {
     case T_BOOLEAN:  return TypeInt::make(constant.as_boolean());
     case T_INT:      return TypeInt::make(constant.as_int());
     case T_CHAR:     return TypeInt::make(constant.as_char());
     case T_BYTE:     return TypeInt::make(constant.as_byte());
     case T_SHORT:    return TypeInt::make(constant.as_short());
     case T_FLOAT:    return TypeF::make(constant.as_float());
     case T_DOUBLE:   return TypeD::make(constant.as_double());
     case T_LONG:     return TypeLong::make(constant.as_long());
     default:         break;
   }
   fatal(err_msg_res("Invalid boxed value type '%s'", type2name(bt)));
   return NULL;
 }
 //------------------------------cast_to_ptr_type-------------------------------
 const Type *TypeInstPtr::cast_to_ptr_type(PTR ptr) const {
   if( ptr == _ptr ) return this;
   // Reconstruct _sig info here since not a problem with later lazy
   // construction, _sig will show up on demand.
   return make(ptr, klass(), klass_is_exact(), const_oop(), _offset, _instance_id);
 }
 //-----------------------------cast_to_exactness-------------------------------
 const Type *TypeInstPtr::cast_to_exactness(bool klass_is_exact) const {
   if( klass_is_exact == _klass_is_exact ) return this;
   if (!UseExactTypes)  return this;
   if (!_klass->is_loaded())  return this;
   ciInstanceKlass* ik = _klass->as_instance_klass();
   if( (ik->is_final() || _const_oop) )  return this;  // cannot clear xk
   if( ik->is_interface() )              return this;  // cannot set xk
   return make(ptr(), klass(), klass_is_exact, const_oop(), _offset, _instance_id);
 }
 //-----------------------------cast_to_instance_id----------------------------
 const TypeOopPtr *TypeInstPtr::cast_to_instance_id(int instance_id) const {
   if( instance_id == _instance_id ) return this;
   return make(_ptr, klass(), _klass_is_exact, const_oop(), _offset, instance_id);
 }
 //------------------------------xmeet_unloaded---------------------------------
 // Compute the MEET of two InstPtrs when at least one is unloaded.
 // Assume classes are different since called after check for same name/class-loader
 const TypeInstPtr *TypeInstPtr::xmeet_unloaded(const TypeInstPtr *tinst) const {
     int off = meet_offset(tinst->offset());
     PTR ptr = meet_ptr(tinst->ptr());
     int instance_id = meet_instance_id(tinst->instance_id());
     const TypeInstPtr *loaded    = is_loaded() ? this  : tinst;
     const TypeInstPtr *unloaded  = is_loaded() ? tinst : this;
     if( loaded->klass()->equals(ciEnv::current()->Object_klass()) ) {
       //
       // Meet unloaded class with java/lang/Object
       //
       // Meet
       //          |                     Unloaded Class
       //  Object  |   TOP    |   AnyNull | Constant |   NotNull |  BOTTOM   |
       //  ===================================================================
       //   TOP    | ..........................Unloaded......................|
       //  AnyNull |  U-AN    |................Unloaded......................|
       // Constant | ... O-NN .................................. |   O-BOT   |
       //  NotNull | ... O-NN .................................. |   O-BOT   |
       //  BOTTOM  | ........................Object-BOTTOM ..................|
       //
       assert(loaded->ptr() != TypePtr::Null, "insanity check");
       //
       if(      loaded->ptr() == TypePtr::TopPTR ) { return unloaded; }
       else if (loaded->ptr() == TypePtr::AnyNull) { return TypeInstPtr::make( ptr, unloaded->klass(), false, NULL, off, instance_id ); }
       else if (loaded->ptr() == TypePtr::BotPTR ) { return TypeInstPtr::BOTTOM; }
       else if (loaded->ptr() == TypePtr::Constant || loaded->ptr() == TypePtr::NotNull) {
         if (unloaded->ptr() == TypePtr::BotPTR  ) { return TypeInstPtr::BOTTOM;  }
         else                                      { return TypeInstPtr::NOTNULL; }
       }
       else if( unloaded->ptr() == TypePtr::TopPTR )  { return unloaded; }
       return unloaded->cast_to_ptr_type(TypePtr::AnyNull)->is_instptr();
     }
     // Both are unloaded, not the same class, not Object
     // Or meet unloaded with a different loaded class, not java/lang/Object
     if( ptr != TypePtr::BotPTR ) {
       return TypeInstPtr::NOTNULL;
     }
     return TypeInstPtr::BOTTOM;
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeInstPtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is Pointer
   switch (t->base()) {          // switch on original type
   case Int:                     // Mixing ints & oops happens when javac
   case Long:                    // reuses local variables
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
   case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
     return this;
   default:                      // All else is a mistake
     typerr(t);
   case MetadataPtr:
   case KlassPtr:
   case RawPtr: return TypePtr::BOTTOM;
   case AryPtr: {                // All arrays inherit from Object class
     const TypeAryPtr *tp = t->is_aryptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     int instance_id = meet_instance_id(tp->instance_id());
     switch (ptr) {
     case TopPTR:
     case AnyNull:                // Fall 'down' to dual of object klass
       if (klass()->equals(ciEnv::current()->Object_klass())) {
         return TypeAryPtr::make(ptr, tp->ary(), tp->klass(), tp->klass_is_exact(), offset, instance_id);
       } else {
         // cannot subclass, so the meet has to fall badly below the centerline
         ptr = NotNull;
         instance_id = InstanceBot;
         return TypeInstPtr::make( ptr, ciEnv::current()->Object_klass(), false, NULL, offset, instance_id);
       }
     case Constant:
     case NotNull:
     case BotPTR:                // Fall down to object klass
       // LCA is object_klass, but if we subclass from the top we can do better
       if( above_centerline(_ptr) ) { // if( _ptr == TopPTR || _ptr == AnyNull )
         // If 'this' (InstPtr) is above the centerline and it is Object class
         // then we can subclass in the Java class hierarchy.
         if (klass()->equals(ciEnv::current()->Object_klass())) {
           // that is, tp's array type is a subtype of my klass
           return TypeAryPtr::make(ptr, (ptr == Constant ? tp->const_oop() : NULL),
                                   tp->ary(), tp->klass(), tp->klass_is_exact(), offset, instance_id);
         }
       }
       // The other case cannot happen, since I cannot be a subtype of an array.
       // The meet falls down to Object class below centerline.
       if( ptr == Constant )
          ptr = NotNull;
       instance_id = InstanceBot;
       return make( ptr, ciEnv::current()->Object_klass(), false, NULL, offset, instance_id );
     default: typerr(t);
     }
   }
   case OopPtr: {                // Meeting to OopPtrs
     // Found a OopPtr type vs self-InstPtr type
     const TypeOopPtr *tp = t->is_oopptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     switch (tp->ptr()) {
     case TopPTR:
     case AnyNull: {
       int instance_id = meet_instance_id(InstanceTop);
       return make(ptr, klass(), klass_is_exact(),
                   (ptr == Constant ? const_oop() : NULL), offset, instance_id);
     }
     case NotNull:
     case BotPTR: {
       int instance_id = meet_instance_id(tp->instance_id());
       return TypeOopPtr::make(ptr, offset, instance_id);
     }
     default: typerr(t);
     }
   }
   case AnyPtr: {                // Meeting to AnyPtrs
     // Found an AnyPtr type vs self-InstPtr type
     const TypePtr *tp = t->is_ptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     switch (tp->ptr()) {
     case Null:
       if( ptr == Null ) return TypePtr::make( AnyPtr, ptr, offset );
       // else fall through to AnyNull
     case TopPTR:
     case AnyNull: {
       int instance_id = meet_instance_id(InstanceTop);
       return make( ptr, klass(), klass_is_exact(),
                    (ptr == Constant ? const_oop() : NULL), offset, instance_id);
     }
     case NotNull:
     case BotPTR:
       return TypePtr::make( AnyPtr, ptr, offset );
     default: typerr(t);
     }
   }
   /*
                  A-top         }
                /   |   \       }  Tops
            B-top A-any C-top   }
               | /  |  \ |      }  Any-nulls
            B-any   |   C-any   }
               |    |    |
            B-con A-con C-con   } constants; not comparable across classes
               |    |    |
            B-not   |   C-not   }
               | \  |  / |      }  not-nulls
            B-bot A-not C-bot   }
                \   |   /       }  Bottoms
                  A-bot         }
   */
   case InstPtr: {                // Meeting 2 Oops?
     // Found an InstPtr sub-type vs self-InstPtr type
     const TypeInstPtr *tinst = t->is_instptr();
     int off = meet_offset( tinst->offset() );
     PTR ptr = meet_ptr( tinst->ptr() );
     int instance_id = meet_instance_id(tinst->instance_id());
     // Check for easy case; klasses are equal (and perhaps not loaded!)
     // If we have constants, then we created oops so classes are loaded
     // and we can handle the constants further down.  This case handles
     // both-not-loaded or both-loaded classes
     if (ptr != Constant && klass()->equals(tinst->klass()) && klass_is_exact() == tinst->klass_is_exact()) {
       return make( ptr, klass(), klass_is_exact(), NULL, off, instance_id );
     }
     // Classes require inspection in the Java klass hierarchy.  Must be loaded.
     ciKlass* tinst_klass = tinst->klass();
     ciKlass* this_klass  = this->klass();
     bool tinst_xk = tinst->klass_is_exact();
     bool this_xk  = this->klass_is_exact();
     if (!tinst_klass->is_loaded() || !this_klass->is_loaded() ) {
       // One of these classes has not been loaded
       const TypeInstPtr *unloaded_meet = xmeet_unloaded(tinst);
 #ifndef PRODUCT
       if( PrintOpto && Verbose ) {
         tty->print("meet of unloaded classes resulted in: "); unloaded_meet->dump(); tty->cr();
         tty->print("  this == "); this->dump(); tty->cr();
         tty->print(" tinst == "); tinst->dump(); tty->cr();
       }
 #endif
       return unloaded_meet;
     }
     // Handle mixing oops and interfaces first.
     if( this_klass->is_interface() && !tinst_klass->is_interface() ) {
       ciKlass *tmp = tinst_klass; // Swap interface around
       tinst_klass = this_klass;
       this_klass = tmp;
       bool tmp2 = tinst_xk;
       tinst_xk = this_xk;
       this_xk = tmp2;
     }
     if (tinst_klass->is_interface() &&
         !(this_klass->is_interface() ||
           // Treat java/lang/Object as an honorary interface,
           // because we need a bottom for the interface hierarchy.
           this_klass == ciEnv::current()->Object_klass())) {
       // Oop meets interface!
       // See if the oop subtypes (implements) interface.
       ciKlass *k;
       bool xk;
       if( this_klass->is_subtype_of( tinst_klass ) ) {
         // Oop indeed subtypes.  Now keep oop or interface depending
         // on whether we are both above the centerline or either is
         // below the centerline.  If we are on the centerline
         // (e.g., Constant vs. AnyNull interface), use the constant.
         k  = below_centerline(ptr) ? tinst_klass : this_klass;
         // If we are keeping this_klass, keep its exactness too.
         xk = below_centerline(ptr) ? tinst_xk    : this_xk;
       } else {                  // Does not implement, fall to Object
         // Oop does not implement interface, so mixing falls to Object
         // just like the verifier does (if both are above the
         // centerline fall to interface)
         k = above_centerline(ptr) ? tinst_klass : ciEnv::current()->Object_klass();
         xk = above_centerline(ptr) ? tinst_xk : false;
         // Watch out for Constant vs. AnyNull interface.
         if (ptr == Constant)  ptr = NotNull;   // forget it was a constant
         instance_id = InstanceBot;
       }
       ciObject* o = NULL;  // the Constant value, if any
       if (ptr == Constant) {
         // Find out which constant.
         o = (this_klass == klass()) ? const_oop() : tinst->const_oop();
       }
       return make( ptr, k, xk, o, off, instance_id );
     }
     // Either oop vs oop or interface vs interface or interface vs Object
     // !!! Here's how the symmetry requirement breaks down into invariants:
     // If we split one up & one down AND they subtype, take the down man.
     // If we split one up & one down AND they do NOT subtype, "fall hard".
     // If both are up and they subtype, take the subtype class.
     // If both are up and they do NOT subtype, "fall hard".
     // If both are down and they subtype, take the supertype class.
     // If both are down and they do NOT subtype, "fall hard".
     // Constants treated as down.
     // Now, reorder the above list; observe that both-down+subtype is also
     // "fall hard"; "fall hard" becomes the default case:
     // If we split one up & one down AND they subtype, take the down man.
     // If both are up and they subtype, take the subtype class.
     // If both are down and they subtype, "fall hard".
     // If both are down and they do NOT subtype, "fall hard".
     // If both are up and they do NOT subtype, "fall hard".
     // If we split one up & one down AND they do NOT subtype, "fall hard".
     // If a proper subtype is exact, and we return it, we return it exactly.
     // If a proper supertype is exact, there can be no subtyping relationship!
     // If both types are equal to the subtype, exactness is and-ed below the
     // centerline and or-ed above it.  (N.B. Constants are always exact.)
     // Check for subtyping:
     ciKlass *subtype = NULL;
     bool subtype_exact = false;
     if( tinst_klass->equals(this_klass) ) {
       subtype = this_klass;
       subtype_exact = below_centerline(ptr) ? (this_xk & tinst_xk) : (this_xk | tinst_xk);
     } else if( !tinst_xk && this_klass->is_subtype_of( tinst_klass ) ) {
       subtype = this_klass;     // Pick subtyping class
       subtype_exact = this_xk;
     } else if( !this_xk && tinst_klass->is_subtype_of( this_klass ) ) {
       subtype = tinst_klass;    // Pick subtyping class
       subtype_exact = tinst_xk;
     }
     if( subtype ) {
       if( above_centerline(ptr) ) { // both are up?
         this_klass = tinst_klass = subtype;
         this_xk = tinst_xk = subtype_exact;
       } else if( above_centerline(this ->_ptr) && !above_centerline(tinst->_ptr) ) {
         this_klass = tinst_klass; // tinst is down; keep down man
         this_xk = tinst_xk;
       } else if( above_centerline(tinst->_ptr) && !above_centerline(this ->_ptr) ) {
         tinst_klass = this_klass; // this is down; keep down man
         tinst_xk = this_xk;
       } else {
         this_xk = subtype_exact;  // either they are equal, or we'll do an LCA
       }
     }
     // Check for classes now being equal
     if (tinst_klass->equals(this_klass)) {
       // If the klasses are equal, the constants may still differ.  Fall to
       // NotNull if they do (neither constant is NULL; that is a special case
       // handled elsewhere).
       ciObject* o = NULL;             // Assume not constant when done
       ciObject* this_oop  = const_oop();
       ciObject* tinst_oop = tinst->const_oop();
       if( ptr == Constant ) {
         if (this_oop != NULL && tinst_oop != NULL &&
             this_oop->equals(tinst_oop) )
           o = this_oop;
         else if (above_centerline(this ->_ptr))
           o = tinst_oop;
         else if (above_centerline(tinst ->_ptr))
           o = this_oop;
         else
           ptr = NotNull;
       }
       return make( ptr, this_klass, this_xk, o, off, instance_id );
     } // Else classes are not equal
     // Since klasses are different, we require a LCA in the Java
     // class hierarchy - which means we have to fall to at least NotNull.
     if( ptr == TopPTR || ptr == AnyNull || ptr == Constant )
       ptr = NotNull;
     instance_id = InstanceBot;
     // Now we find the LCA of Java classes
     ciKlass* k = this_klass->least_common_ancestor(tinst_klass);
     return make( ptr, k, false, NULL, off, instance_id );
   } // End of case InstPtr
   } // End of switch
   return this;                  // Return the double constant
 }
 //------------------------java_mirror_type--------------------------------------
 ciType* TypeInstPtr::java_mirror_type() const {
   // must be a singleton type
   if( const_oop() == NULL )  return NULL;
   // must be of type java.lang.Class
   if( klass() != ciEnv::current()->Class_klass() )  return NULL;
   return const_oop()->as_instance()->java_mirror_type();
 }
 //------------------------------xdual------------------------------------------
 // Dual: do NOT dual on klasses.  This means I do NOT understand the Java
 // inheritance mechanism.
 const Type *TypeInstPtr::xdual() const {
   return new TypeInstPtr( dual_ptr(), klass(), klass_is_exact(), const_oop(), dual_offset(), dual_instance_id()  );
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeInstPtr::eq( const Type *t ) const {
   const TypeInstPtr *p = t->is_instptr();
   return
     klass()->equals(p->klass()) &&
     TypeOopPtr::eq(p);          // Check sub-type stuff
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeInstPtr::hash(void) const {
   int hash = klass()->hash() + TypeOopPtr::hash();
   return hash;
 }
 //------------------------------dump2------------------------------------------
 // Dump oop Type
 #ifndef PRODUCT
 void TypeInstPtr::dump2( Dict &d, uint depth, outputStream *st ) const {
   // Print the name of the klass.
   klass()->print_name_on(st);
   switch( _ptr ) {
   case Constant:
     // TO DO: Make CI print the hex address of the underlying oop.
     if (WizardMode || Verbose) {
       const_oop()->print_oop(st);
     }
   case BotPTR:
     if (!WizardMode && !Verbose) {
       if( _klass_is_exact ) st->print(":exact");
       break;
     }
   case TopPTR:
   case AnyNull:
   case NotNull:
     st->print(":%s", ptr_msg[_ptr]);
     if( _klass_is_exact ) st->print(":exact");
     break;
   }
   if( _offset ) {               // Dump offset, if any
     if( _offset == OffsetBot )      st->print("+any");
     else if( _offset == OffsetTop ) st->print("+unknown");
     else st->print("+%d", _offset);
   }
   st->print(" *");
   if (_instance_id == InstanceTop)
     st->print(",iid=top");
   else if (_instance_id != InstanceBot)
     st->print(",iid=%d",_instance_id);
 }
 #endif
 //------------------------------add_offset-------------------------------------
 const TypePtr *TypeInstPtr::add_offset( intptr_t offset ) const {
   return make( _ptr, klass(), klass_is_exact(), const_oop(), xadd_offset(offset), _instance_id );
 }
 //=============================================================================
 // Convenience common pre-built types.
 const TypeAryPtr *TypeAryPtr::RANGE;
 const TypeAryPtr *TypeAryPtr::OOPS;
 const TypeAryPtr *TypeAryPtr::NARROWOOPS;
 const TypeAryPtr *TypeAryPtr::BYTES;
 const TypeAryPtr *TypeAryPtr::SHORTS;
 const TypeAryPtr *TypeAryPtr::CHARS;
 const TypeAryPtr *TypeAryPtr::INTS;
 const TypeAryPtr *TypeAryPtr::LONGS;
 const TypeAryPtr *TypeAryPtr::FLOATS;
 const TypeAryPtr *TypeAryPtr::DOUBLES;
 //------------------------------make-------------------------------------------
 const TypeAryPtr *TypeAryPtr::make( PTR ptr, const TypeAry *ary, ciKlass* k, bool xk, int offset, int instance_id ) {
   assert(!(k == NULL && ary->_elem->isa_int()),
          "integral arrays must be pre-equipped with a class");
   if (!xk)  xk = ary->ary_must_be_exact();
   assert(instance_id <= 0 || xk || !UseExactTypes, "instances are always exactly typed");
   if (!UseExactTypes)  xk = (ptr == Constant);
   return (TypeAryPtr*)(new TypeAryPtr(ptr, NULL, ary, k, xk, offset, instance_id, false))->hashcons();
 }
 //------------------------------make-------------------------------------------
 const TypeAryPtr *TypeAryPtr::make( PTR ptr, ciObject* o, const TypeAry *ary, ciKlass* k, bool xk, int offset, int instance_id, bool is_autobox_cache) {
   assert(!(k == NULL && ary->_elem->isa_int()),
          "integral arrays must be pre-equipped with a class");
   assert( (ptr==Constant && o) || (ptr!=Constant && !o), "" );
   if (!xk)  xk = (o != NULL) || ary->ary_must_be_exact();
   assert(instance_id <= 0 || xk || !UseExactTypes, "instances are always exactly typed");
   if (!UseExactTypes)  xk = (ptr == Constant);
   return (TypeAryPtr*)(new TypeAryPtr(ptr, o, ary, k, xk, offset, instance_id, is_autobox_cache))->hashcons();
 }
 //------------------------------cast_to_ptr_type-------------------------------
 const Type *TypeAryPtr::cast_to_ptr_type(PTR ptr) const {
   if( ptr == _ptr ) return this;
   return make(ptr, const_oop(), _ary, klass(), klass_is_exact(), _offset, _instance_id);
 }
 //-----------------------------cast_to_exactness-------------------------------
 const Type *TypeAryPtr::cast_to_exactness(bool klass_is_exact) const {
   if( klass_is_exact == _klass_is_exact ) return this;
   if (!UseExactTypes)  return this;
   if (_ary->ary_must_be_exact())  return this;  // cannot clear xk
   return make(ptr(), const_oop(), _ary, klass(), klass_is_exact, _offset, _instance_id);
 }
 //-----------------------------cast_to_instance_id----------------------------
 const TypeOopPtr *TypeAryPtr::cast_to_instance_id(int instance_id) const {
   if( instance_id == _instance_id ) return this;
   return make(_ptr, const_oop(), _ary, klass(), _klass_is_exact, _offset, instance_id);
 }
 //-----------------------------narrow_size_type-------------------------------
 // Local cache for arrayOopDesc::max_array_length(etype),
 // which is kind of slow (and cached elsewhere by other users).
 static jint max_array_length_cache[T_CONFLICT+1];
 static jint max_array_length(BasicType etype) {
   jint& cache = max_array_length_cache[etype];
   jint res = cache;
   if (res == 0) {
     switch (etype) {
     case T_NARROWOOP:
       etype = T_OBJECT;
       break;
     case T_NARROWKLASS:
     case T_CONFLICT:
     case T_ILLEGAL:
     case T_VOID:
       etype = T_BYTE;           // will produce conservatively high value
     }
     cache = res = arrayOopDesc::max_array_length(etype);
   }
   return res;
 }
 // Narrow the given size type to the index range for the given array base type.
 // Return NULL if the resulting int type becomes empty.
 const TypeInt* TypeAryPtr::narrow_size_type(const TypeInt* size) const {
   jint hi = size->_hi;
   jint lo = size->_lo;
   jint min_lo = 0;
   jint max_hi = max_array_length(elem()->basic_type());
   //if (index_not_size)  --max_hi;     // type of a valid array index, FTR
   bool chg = false;
   if (lo < min_lo) {
     lo = min_lo;
     if (size->is_con()) {
       hi = lo;
     }
     chg = true;
   }
   if (hi > max_hi) {
     hi = max_hi;
     if (size->is_con()) {
       lo = hi;
     }
     chg = true;
   }
   // Negative length arrays will produce weird intermediate dead fast-path code
   if (lo > hi)
     return TypeInt::ZERO;
   if (!chg)
     return size;
   return TypeInt::make(lo, hi, Type::WidenMin);
 }
 //-------------------------------cast_to_size----------------------------------
 const TypeAryPtr* TypeAryPtr::cast_to_size(const TypeInt* new_size) const {
   assert(new_size != NULL, "");
   new_size = narrow_size_type(new_size);
   if (new_size == size())  return this;
   const TypeAry* new_ary = TypeAry::make(elem(), new_size, is_stable());
   return make(ptr(), const_oop(), new_ary, klass(), klass_is_exact(), _offset, _instance_id);
 }
 //------------------------------cast_to_stable---------------------------------
 const TypeAryPtr* TypeAryPtr::cast_to_stable(bool stable, int stable_dimension) const {
   if (stable_dimension <= 0 || (stable_dimension == 1 && stable == this->is_stable()))
     return this;
   const Type* elem = this->elem();
   const TypePtr* elem_ptr = elem->make_ptr();
   if (stable_dimension > 1 && elem_ptr != NULL && elem_ptr->isa_aryptr()) {
     // If this is widened from a narrow oop, TypeAry::make will re-narrow it.
     elem = elem_ptr = elem_ptr->is_aryptr()->cast_to_stable(stable, stable_dimension - 1);
   }
   const TypeAry* new_ary = TypeAry::make(elem, size(), stable);
   return make(ptr(), const_oop(), new_ary, klass(), klass_is_exact(), _offset, _instance_id);
 }
 //-----------------------------stable_dimension--------------------------------
 int TypeAryPtr::stable_dimension() const {
   if (!is_stable())  return 0;
   int dim = 1;
   const TypePtr* elem_ptr = elem()->make_ptr();
   if (elem_ptr != NULL && elem_ptr->isa_aryptr())
     dim += elem_ptr->is_aryptr()->stable_dimension();
   return dim;
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeAryPtr::eq( const Type *t ) const {
   const TypeAryPtr *p = t->is_aryptr();
   return
     _ary == p->_ary &&  // Check array
     TypeOopPtr::eq(p);  // Check sub-parts
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeAryPtr::hash(void) const {
   return (intptr_t)_ary + TypeOopPtr::hash();
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeAryPtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is Pointer
   switch (t->base()) {          // switch on original type
   // Mixing ints & oops happens when javac reuses local variables
   case Int:
   case Long:
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
   case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
     return this;
   default:                      // All else is a mistake
     typerr(t);
   case OopPtr: {                // Meeting to OopPtrs
     // Found a OopPtr type vs self-AryPtr type
     const TypeOopPtr *tp = t->is_oopptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     switch (tp->ptr()) {
     case TopPTR:
     case AnyNull: {
       int instance_id = meet_instance_id(InstanceTop);
       return make(ptr, (ptr == Constant ? const_oop() : NULL),
                   _ary, _klass, _klass_is_exact, offset, instance_id);
     }
     case BotPTR:
     case NotNull: {
       int instance_id = meet_instance_id(tp->instance_id());
       return TypeOopPtr::make(ptr, offset, instance_id);
     }
     default: ShouldNotReachHere();
     }
   }
   case AnyPtr: {                // Meeting two AnyPtrs
     // Found an AnyPtr type vs self-AryPtr type
     const TypePtr *tp = t->is_ptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     switch (tp->ptr()) {
     case TopPTR:
       return this;
     case BotPTR:
     case NotNull:
       return TypePtr::make(AnyPtr, ptr, offset);
     case Null:
       if( ptr == Null ) return TypePtr::make(AnyPtr, ptr, offset);
       // else fall through to AnyNull
     case AnyNull: {
       int instance_id = meet_instance_id(InstanceTop);
       return make( ptr, (ptr == Constant ? const_oop() : NULL),
                   _ary, _klass, _klass_is_exact, offset, instance_id);
     }
     default: ShouldNotReachHere();
     }
   }
   case MetadataPtr:
   case KlassPtr:
   case RawPtr: return TypePtr::BOTTOM;
   case AryPtr: {                // Meeting 2 references?
     const TypeAryPtr *tap = t->is_aryptr();
     int off = meet_offset(tap->offset());
     const TypeAry *tary = _ary->meet(tap->_ary)->is_ary();
     PTR ptr = meet_ptr(tap->ptr());
     int instance_id = meet_instance_id(tap->instance_id());
     ciKlass* lazy_klass = NULL;
     if (tary->_elem->isa_int()) {
       // Integral array element types have irrelevant lattice relations.
       // It is the klass that determines array layout, not the element type.
       if (_klass == NULL)
         lazy_klass = tap->_klass;
       else if (tap->_klass == NULL || tap->_klass == _klass) {
         lazy_klass = _klass;
       } else {
         // Something like byte[int+] meets char[int+].
         // This must fall to bottom, not (int[-128..65535])[int+].
         instance_id = InstanceBot;
         tary = TypeAry::make(Type::BOTTOM, tary->_size, tary->_stable);
       }
     } else // Non integral arrays.
     // Must fall to bottom if exact klasses in upper lattice
     // are not equal or super klass is exact.
     if ( above_centerline(ptr) && klass() != tap->klass() &&
          // meet with top[] and bottom[] are processed further down:
          tap ->_klass != NULL  && this->_klass != NULL   &&
          // both are exact and not equal:
         ((tap ->_klass_is_exact && this->_klass_is_exact) ||
          // 'tap'  is exact and super or unrelated:
          (tap ->_klass_is_exact && !tap->klass()->is_subtype_of(klass())) ||
          // 'this' is exact and super or unrelated:
          (this->_klass_is_exact && !klass()->is_subtype_of(tap->klass())))) {
       tary = TypeAry::make(Type::BOTTOM, tary->_size, tary->_stable);
       return make( NotNull, NULL, tary, lazy_klass, false, off, InstanceBot );
     }
     bool xk = false;
     switch (tap->ptr()) {
     case AnyNull:
     case TopPTR:
       // Compute new klass on demand, do not use tap->_klass
       xk = (tap->_klass_is_exact | this->_klass_is_exact);
       return make( ptr, const_oop(), tary, lazy_klass, xk, off, instance_id );
     case Constant: {
       ciObject* o = const_oop();
       if( _ptr == Constant ) {
         if( tap->const_oop() != NULL && !o->equals(tap->const_oop()) ) {
           xk = (klass() == tap->klass());
           ptr = NotNull;
           o = NULL;
           instance_id = InstanceBot;
         } else {
           xk = true;
         }
       } else if( above_centerline(_ptr) ) {
         o = tap->const_oop();
         xk = true;
       } else {
         // Only precise for identical arrays
         xk = this->_klass_is_exact && (klass() == tap->klass());
       }
       return TypeAryPtr::make( ptr, o, tary, lazy_klass, xk, off, instance_id );
     }
     case NotNull:
     case BotPTR:
       // Compute new klass on demand, do not use tap->_klass
       if (above_centerline(this->_ptr))
             xk = tap->_klass_is_exact;
       else if (above_centerline(tap->_ptr))
             xk = this->_klass_is_exact;
       else  xk = (tap->_klass_is_exact & this->_klass_is_exact) &&
               (klass() == tap->klass()); // Only precise for identical arrays
       return TypeAryPtr::make( ptr, NULL, tary, lazy_klass, xk, off, instance_id );
     default: ShouldNotReachHere();
     }
   }
   // All arrays inherit from Object class
   case InstPtr: {
     const TypeInstPtr *tp = t->is_instptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     int instance_id = meet_instance_id(tp->instance_id());
     switch (ptr) {
     case TopPTR:
     case AnyNull:                // Fall 'down' to dual of object klass
       if( tp->klass()->equals(ciEnv::current()->Object_klass()) ) {
         return TypeAryPtr::make( ptr, _ary, _klass, _klass_is_exact, offset, instance_id );
       } else {
         // cannot subclass, so the meet has to fall badly below the centerline
         ptr = NotNull;
         instance_id = InstanceBot;
         return TypeInstPtr::make( ptr, ciEnv::current()->Object_klass(), false, NULL,offset, instance_id);
       }
     case Constant:
     case NotNull:
     case BotPTR:                // Fall down to object klass
       // LCA is object_klass, but if we subclass from the top we can do better
       if (above_centerline(tp->ptr())) {
         // If 'tp'  is above the centerline and it is Object class
         // then we can subclass in the Java class hierarchy.
         if( tp->klass()->equals(ciEnv::current()->Object_klass()) ) {
           // that is, my array type is a subtype of 'tp' klass
           return make( ptr, (ptr == Constant ? const_oop() : NULL),
                        _ary, _klass, _klass_is_exact, offset, instance_id );
         }
       }
       // The other case cannot happen, since t cannot be a subtype of an array.
       // The meet falls down to Object class below centerline.
       if( ptr == Constant )
          ptr = NotNull;
       instance_id = InstanceBot;
       return TypeInstPtr::make( ptr, ciEnv::current()->Object_klass(), false, NULL,offset, instance_id);
     default: typerr(t);
     }
   }
   }
   return this;                  // Lint noise
 }
 //------------------------------xdual------------------------------------------
 // Dual: compute field-by-field dual
 const Type *TypeAryPtr::xdual() const {
   return new TypeAryPtr( dual_ptr(), _const_oop, _ary->dual()->is_ary(),_klass, _klass_is_exact, dual_offset(), dual_instance_id(), is_autobox_cache() );
 }
 //----------------------interface_vs_oop---------------------------------------
 #ifdef ASSERT
 bool TypeAryPtr::interface_vs_oop(const Type *t) const {
   const TypeAryPtr* t_aryptr = t->isa_aryptr();
   if (t_aryptr) {
     return _ary->interface_vs_oop(t_aryptr->_ary);
   }
   return false;
 }
 #endif
 //------------------------------dump2------------------------------------------
 #ifndef PRODUCT
 void TypeAryPtr::dump2( Dict &d, uint depth, outputStream *st ) const {
   _ary->dump2(d,depth,st);
   switch( _ptr ) {
   case Constant:
     const_oop()->print(st);
     break;
   case BotPTR:
     if (!WizardMode && !Verbose) {
       if( _klass_is_exact ) st->print(":exact");
       break;
     }
   case TopPTR:
   case AnyNull:
   case NotNull:
     st->print(":%s", ptr_msg[_ptr]);
     if( _klass_is_exact ) st->print(":exact");
     break;
   }
   if( _offset != 0 ) {
     int header_size = objArrayOopDesc::header_size() * wordSize;
     if( _offset == OffsetTop )       st->print("+undefined");
     else if( _offset == OffsetBot )  st->print("+any");
     else if( _offset < header_size ) st->print("+%d", _offset);
     else {
       BasicType basic_elem_type = elem()->basic_type();
       int array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type);
       int elem_size = type2aelembytes(basic_elem_type);
       st->print("[%d]", (_offset - array_base)/elem_size);
     }
   }
   st->print(" *");
   if (_instance_id == InstanceTop)
     st->print(",iid=top");
   else if (_instance_id != InstanceBot)
     st->print(",iid=%d",_instance_id);
 }
 #endif
 bool TypeAryPtr::empty(void) const {
   if (_ary->empty())       return true;
   return TypeOopPtr::empty();
 }
 //------------------------------add_offset-------------------------------------
 const TypePtr *TypeAryPtr::add_offset( intptr_t offset ) const {
   return make( _ptr, _const_oop, _ary, _klass, _klass_is_exact, xadd_offset(offset), _instance_id );
 }
 //=============================================================================
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeNarrowPtr::hash(void) const {
   return _ptrtype->hash() + 7;
 }
 bool TypeNarrowPtr::singleton(void) const {    // TRUE if type is a singleton
   return _ptrtype->singleton();
 }
 bool TypeNarrowPtr::empty(void) const {
   return _ptrtype->empty();
 }
 intptr_t TypeNarrowPtr::get_con() const {
   return _ptrtype->get_con();
 }
 bool TypeNarrowPtr::eq( const Type *t ) const {
   const TypeNarrowPtr* tc = isa_same_narrowptr(t);
   if (tc != NULL) {
     if (_ptrtype->base() != tc->_ptrtype->base()) {
       return false;
     }
     return tc->_ptrtype->eq(_ptrtype);
   }
   return false;
 }
 const Type *TypeNarrowPtr::xdual() const {    // Compute dual right now.
   const TypePtr* odual = _ptrtype->dual()->is_ptr();
   return make_same_narrowptr(odual);
 }
 const Type *TypeNarrowPtr::filter( const Type *kills ) const {
   if (isa_same_narrowptr(kills)) {
     const Type* ft =_ptrtype->filter(is_same_narrowptr(kills)->_ptrtype);
     if (ft->empty())
       return Type::TOP;           // Canonical empty value
     if (ft->isa_ptr()) {
       return make_hash_same_narrowptr(ft->isa_ptr());
     }
     return ft;
   } else if (kills->isa_ptr()) {
     const Type* ft = _ptrtype->join(kills);
     if (ft->empty())
       return Type::TOP;           // Canonical empty value
     return ft;
   } else {
     return Type::TOP;
   }
 }
 //------------------------------xmeet------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeNarrowPtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   if (t->base() == base()) {
     const Type* result = _ptrtype->xmeet(t->make_ptr());
     if (result->isa_ptr()) {
       return make_hash_same_narrowptr(result->is_ptr());
     }
     return result;
   }
   // Current "this->_base" is NarrowKlass or NarrowOop
   switch (t->base()) {          // switch on original type
   case Int:                     // Mixing ints & oops happens when javac
   case Long:                    // reuses local variables
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case AnyPtr:
   case RawPtr:
   case OopPtr:
   case InstPtr:
   case AryPtr:
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
   case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
     return this;
   default:                      // All else is a mistake
     typerr(t);
   } // End of switch
   return this;
 }
 #ifndef PRODUCT
 void TypeNarrowPtr::dump2( Dict & d, uint depth, outputStream *st ) const {
   _ptrtype->dump2(d, depth, st);
 }
 #endif
 const TypeNarrowOop *TypeNarrowOop::BOTTOM;
 const TypeNarrowOop *TypeNarrowOop::NULL_PTR;
 const TypeNarrowOop* TypeNarrowOop::make(const TypePtr* type) {
   return (const TypeNarrowOop*)(new TypeNarrowOop(type))->hashcons();
 }
 #ifndef PRODUCT
 void TypeNarrowOop::dump2( Dict & d, uint depth, outputStream *st ) const {
   st->print("narrowoop: ");
   TypeNarrowPtr::dump2(d, depth, st);
 }
 #endif
 const TypeNarrowKlass *TypeNarrowKlass::NULL_PTR;
 const TypeNarrowKlass* TypeNarrowKlass::make(const TypePtr* type) {
   return (const TypeNarrowKlass*)(new TypeNarrowKlass(type))->hashcons();
 }
 #ifndef PRODUCT
 void TypeNarrowKlass::dump2( Dict & d, uint depth, outputStream *st ) const {
   st->print("narrowklass: ");
   TypeNarrowPtr::dump2(d, depth, st);
 }
 #endif
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeMetadataPtr::eq( const Type *t ) const {
   const TypeMetadataPtr *a = (const TypeMetadataPtr*)t;
   ciMetadata* one = metadata();
   ciMetadata* two = a->metadata();
   if (one == NULL || two == NULL) {
     return (one == two) && TypePtr::eq(t);
   } else {
     return one->equals(two) && TypePtr::eq(t);
   }
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeMetadataPtr::hash(void) const {
   return
     (metadata() ? metadata()->hash() : 0) +
     TypePtr::hash();
 }
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants
 bool TypeMetadataPtr::singleton(void) const {
   // detune optimizer to not generate constant metadta + constant offset as a constant!
   // TopPTR, Null, AnyNull, Constant are all singletons
   return (_offset == 0) && !below_centerline(_ptr);
 }
 //------------------------------add_offset-------------------------------------
 const TypePtr *TypeMetadataPtr::add_offset( intptr_t offset ) const {
   return make( _ptr, _metadata, xadd_offset(offset));
 }
 //-----------------------------filter------------------------------------------
 // Do not allow interface-vs.-noninterface joins to collapse to top.
 const Type *TypeMetadataPtr::filter( const Type *kills ) const {
   const TypeMetadataPtr* ft = join(kills)->isa_metadataptr();
   if (ft == NULL || ft->empty())
     return Type::TOP;           // Canonical empty value
   return ft;
 }
  //------------------------------get_con----------------------------------------
 intptr_t TypeMetadataPtr::get_con() const {
   assert( _ptr == Null || _ptr == Constant, "" );
   assert( _offset >= 0, "" );
   if (_offset != 0) {
     // After being ported to the compiler interface, the compiler no longer
     // directly manipulates the addresses of oops.  Rather, it only has a pointer
     // to a handle at compile time.  This handle is embedded in the generated
     // code and dereferenced at the time the nmethod is made.  Until that time,
     // it is not reasonable to do arithmetic with the addresses of oops (we don't
     // have access to the addresses!).  This does not seem to currently happen,
     // but this assertion here is to help prevent its occurence.
     tty->print_cr("Found oop constant with non-zero offset");
     ShouldNotReachHere();
   }
   return (intptr_t)metadata()->constant_encoding();
 }
 //------------------------------cast_to_ptr_type-------------------------------
 const Type *TypeMetadataPtr::cast_to_ptr_type(PTR ptr) const {
   if( ptr == _ptr ) return this;
   return make(ptr, metadata(), _offset);
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeMetadataPtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is OopPtr
   switch (t->base()) {          // switch on original type
   case Int:                     // Mixing ints & oops happens when javac
   case Long:                    // reuses local variables
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
   case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
     return this;
   default:                      // All else is a mistake
     typerr(t);
   case AnyPtr: {
     // Found an AnyPtr type vs self-OopPtr type
     const TypePtr *tp = t->is_ptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     switch (tp->ptr()) {
     case Null:
       if (ptr == Null)  return TypePtr::make(AnyPtr, ptr, offset);
       // else fall through:
     case TopPTR:
     case AnyNull: {
       return make(ptr, NULL, offset);
     }
     case BotPTR:
     case NotNull:
       return TypePtr::make(AnyPtr, ptr, offset);
     default: typerr(t);
     }
   }
   case RawPtr:
   case KlassPtr:
   case OopPtr:
   case InstPtr:
   case AryPtr:
     return TypePtr::BOTTOM;     // Oop meet raw is not well defined
   case MetadataPtr: {
     const TypeMetadataPtr *tp = t->is_metadataptr();
     int offset = meet_offset(tp->offset());
     PTR tptr = tp->ptr();
     PTR ptr = meet_ptr(tptr);
     ciMetadata* md = (tptr == TopPTR) ? metadata() : tp->metadata();
     if (tptr == TopPTR || _ptr == TopPTR ||
         metadata()->equals(tp->metadata())) {
       return make(ptr, md, offset);
     }
     // metadata is different
     if( ptr == Constant ) {  // Cannot be equal constants, so...
       if( tptr == Constant && _ptr != Constant)  return t;
       if( _ptr == Constant && tptr != Constant)  return this;
       ptr = NotNull;            // Fall down in lattice
     }
     return make(ptr, NULL, offset);
     break;
   }
   } // End of switch
   return this;                  // Return the double constant
 }
 //------------------------------xdual------------------------------------------
 // Dual of a pure metadata pointer.
 const Type *TypeMetadataPtr::xdual() const {
   return new TypeMetadataPtr(dual_ptr(), metadata(), dual_offset());
 }
 //------------------------------dump2------------------------------------------
 #ifndef PRODUCT
 void TypeMetadataPtr::dump2( Dict &d, uint depth, outputStream *st ) const {
   st->print("metadataptr:%s", ptr_msg[_ptr]);
   if( metadata() ) st->print(INTPTR_FORMAT, metadata());
   switch( _offset ) {
   case OffsetTop: st->print("+top"); break;
   case OffsetBot: st->print("+any"); break;
   case         0: break;
   default:        st->print("+%d",_offset); break;
   }
 }
 #endif
 //=============================================================================
 // Convenience common pre-built type.
 const TypeMetadataPtr *TypeMetadataPtr::BOTTOM;
 TypeMetadataPtr::TypeMetadataPtr(PTR ptr, ciMetadata* metadata, int offset):
   TypePtr(MetadataPtr, ptr, offset), _metadata(metadata) {
 }
 const TypeMetadataPtr* TypeMetadataPtr::make(ciMethod* m) {
   return make(Constant, m, 0);
 }
 const TypeMetadataPtr* TypeMetadataPtr::make(ciMethodData* m) {
   return make(Constant, m, 0);
 }
 //------------------------------make-------------------------------------------
 // Create a meta data constant
 const TypeMetadataPtr *TypeMetadataPtr::make(PTR ptr, ciMetadata* m, int offset) {
   assert(m == NULL || !m->is_klass(), "wrong type");
   return (TypeMetadataPtr*)(new TypeMetadataPtr(ptr, m, offset))->hashcons();
 }
 //=============================================================================
 // Convenience common pre-built types.
 // Not-null object klass or below
 const TypeKlassPtr *TypeKlassPtr::OBJECT;
 const TypeKlassPtr *TypeKlassPtr::OBJECT_OR_NULL;
 //------------------------------TypeKlassPtr-----------------------------------
 TypeKlassPtr::TypeKlassPtr( PTR ptr, ciKlass* klass, int offset )
   : TypePtr(KlassPtr, ptr, offset), _klass(klass), _klass_is_exact(ptr == Constant) {
 }
 //------------------------------make-------------------------------------------
 // ptr to klass 'k', if Constant, or possibly to a sub-klass if not a Constant
 const TypeKlassPtr *TypeKlassPtr::make( PTR ptr, ciKlass* k, int offset ) {
   assert( k != NULL, "Expect a non-NULL klass");
   assert(k->is_instance_klass() || k->is_array_klass(), "Incorrect type of klass oop");
   TypeKlassPtr *r =
     (TypeKlassPtr*)(new TypeKlassPtr(ptr, k, offset))->hashcons();
   return r;
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeKlassPtr::eq( const Type *t ) const {
   const TypeKlassPtr *p = t->is_klassptr();
   return
     klass()->equals(p->klass()) &&
     TypePtr::eq(p);
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeKlassPtr::hash(void) const {
   return klass()->hash() + TypePtr::hash();
 }
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants
 bool TypeKlassPtr::singleton(void) const {
   // detune optimizer to not generate constant klass + constant offset as a constant!
   // TopPTR, Null, AnyNull, Constant are all singletons
   return (_offset == 0) && !below_centerline(_ptr);
 }
 //----------------------compute_klass------------------------------------------
 // Compute the defining klass for this class
 ciKlass* TypeAryPtr::compute_klass(DEBUG_ONLY(bool verify)) const {
   // Compute _klass based on element type.
   ciKlass* k_ary = NULL;
   const TypeInstPtr *tinst;
   const TypeAryPtr *tary;
   const Type* el = elem();
   if (el->isa_narrowoop()) {
     el = el->make_ptr();
   }
   // Get element klass
   if ((tinst = el->isa_instptr()) != NULL) {
     // Compute array klass from element klass
     k_ary = ciObjArrayKlass::make(tinst->klass());
   } else if ((tary = el->isa_aryptr()) != NULL) {
     // Compute array klass from element klass
     ciKlass* k_elem = tary->klass();
     // If element type is something like bottom[], k_elem will be null.
     if (k_elem != NULL)
       k_ary = ciObjArrayKlass::make(k_elem);
   } else if ((el->base() == Type::Top) ||
              (el->base() == Type::Bottom)) {
     // element type of Bottom occurs from meet of basic type
     // and object; Top occurs when doing join on Bottom.
     // Leave k_ary at NULL.
   } else {
     // Cannot compute array klass directly from basic type,
     // since subtypes of TypeInt all have basic type T_INT.
 #ifdef ASSERT
     if (verify && el->isa_int()) {
       // Check simple cases when verifying klass.
       BasicType bt = T_ILLEGAL;
       if (el == TypeInt::BYTE) {
         bt = T_BYTE;
       } else if (el == TypeInt::SHORT) {
         bt = T_SHORT;
       } else if (el == TypeInt::CHAR) {
         bt = T_CHAR;
       } else if (el == TypeInt::INT) {
         bt = T_INT;
       } else {
         return _klass; // just return specified klass
       }
       return ciTypeArrayKlass::make(bt);
     }
 #endif
     assert(!el->isa_int(),
            "integral arrays must be pre-equipped with a class");
     // Compute array klass directly from basic type
     k_ary = ciTypeArrayKlass::make(el->basic_type());
   }
   return k_ary;
 }
 //------------------------------klass------------------------------------------
 // Return the defining klass for this class
 ciKlass* TypeAryPtr::klass() const {
   if( _klass ) return _klass;   // Return cached value, if possible
   // Oops, need to compute _klass and cache it
   ciKlass* k_ary = compute_klass();
   if( this != TypeAryPtr::OOPS && this->dual() != TypeAryPtr::OOPS ) {
     // The _klass field acts as a cache of the underlying
     // ciKlass for this array type.  In order to set the field,
     // we need to cast away const-ness.
     //
     // IMPORTANT NOTE: we *never* set the _klass field for the
     // type TypeAryPtr::OOPS.  This Type is shared between all
     // active compilations.  However, the ciKlass which represents
     // this Type is *not* shared between compilations, so caching
     // this value would result in fetching a dangling pointer.
     //
     // Recomputing the underlying ciKlass for each request is
     // a bit less efficient than caching, but calls to
     // TypeAryPtr::OOPS->klass() are not common enough to matter.
     ((TypeAryPtr*)this)->_klass = k_ary;
     if (UseCompressedOops && k_ary != NULL && k_ary->is_obj_array_klass() &&
         _offset != 0 && _offset != arrayOopDesc::length_offset_in_bytes()) {
       ((TypeAryPtr*)this)->_is_ptr_to_narrowoop = true;
     }
   }
   return k_ary;
 }
 //------------------------------add_offset-------------------------------------
 // Access internals of klass object
 const TypePtr *TypeKlassPtr::add_offset( intptr_t offset ) const {
   return make( _ptr, klass(), xadd_offset(offset) );
 }
 //------------------------------cast_to_ptr_type-------------------------------
 const Type *TypeKlassPtr::cast_to_ptr_type(PTR ptr) const {
   assert(_base == KlassPtr, "subclass must override cast_to_ptr_type");
   if( ptr == _ptr ) return this;
   return make(ptr, _klass, _offset);
 }
 //-----------------------------cast_to_exactness-------------------------------
 const Type *TypeKlassPtr::cast_to_exactness(bool klass_is_exact) const {
   if( klass_is_exact == _klass_is_exact ) return this;
   if (!UseExactTypes)  return this;
   return make(klass_is_exact ? Constant : NotNull, _klass, _offset);
 }
 //-----------------------------as_instance_type--------------------------------
 // Corresponding type for an instance of the given class.
 // It will be NotNull, and exact if and only if the klass type is exact.
 const TypeOopPtr* TypeKlassPtr::as_instance_type() const {
   ciKlass* k = klass();
   bool    xk = klass_is_exact();
   //return TypeInstPtr::make(TypePtr::NotNull, k, xk, NULL, 0);
   const TypeOopPtr* toop = TypeOopPtr::make_from_klass_raw(k);
   guarantee(toop != NULL, "need type for given klass");
   toop = toop->cast_to_ptr_type(TypePtr::NotNull)->is_oopptr();
   return toop->cast_to_exactness(xk)->is_oopptr();
 }
 //------------------------------xmeet------------------------------------------
 // Compute the MEET of two types, return a new Type object.
 const Type    *TypeKlassPtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is Pointer
   switch (t->base()) {          // switch on original type
   case Int:                     // Mixing ints & oops happens when javac
   case Long:                    // reuses local variables
   case FloatTop:
   case FloatCon:
   case FloatBot:
   case DoubleTop:
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
   case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
     return this;
   default:                      // All else is a mistake
     typerr(t);
   case AnyPtr: {                // Meeting to AnyPtrs
     // Found an AnyPtr type vs self-KlassPtr type
     const TypePtr *tp = t->is_ptr();
     int offset = meet_offset(tp->offset());
     PTR ptr = meet_ptr(tp->ptr());
     switch (tp->ptr()) {
     case TopPTR:
       return this;
     case Null:
       if( ptr == Null ) return TypePtr::make( AnyPtr, ptr, offset );
     case AnyNull:
       return make( ptr, klass(), offset );
     case BotPTR:
     case NotNull:
       return TypePtr::make(AnyPtr, ptr, offset);
     default: typerr(t);
     }
   }
   case RawPtr:
   case MetadataPtr:
   case OopPtr:
   case AryPtr:                  // Meet with AryPtr
   case InstPtr:                 // Meet with InstPtr
     return TypePtr::BOTTOM;
   //
   //             A-top         }
   //           /   |   \       }  Tops
   //       B-top A-any C-top   }
   //          | /  |  \ |      }  Any-nulls
   //       B-any   |   C-any   }
   //          |    |    |
   //       B-con A-con C-con   } constants; not comparable across classes
   //          |    |    |
   //       B-not   |   C-not   }
   //          | \  |  / |      }  not-nulls
   //       B-bot A-not C-bot   }
   //           \   |   /       }  Bottoms
   //             A-bot         }
   //
   case KlassPtr: {  // Meet two KlassPtr types
     const TypeKlassPtr *tkls = t->is_klassptr();
     int  off     = meet_offset(tkls->offset());
     PTR  ptr     = meet_ptr(tkls->ptr());
     // Check for easy case; klasses are equal (and perhaps not loaded!)
     // If we have constants, then we created oops so classes are loaded
     // and we can handle the constants further down.  This case handles
     // not-loaded classes
     if( ptr != Constant && tkls->klass()->equals(klass()) ) {
       return make( ptr, klass(), off );
     }
     // Classes require inspection in the Java klass hierarchy.  Must be loaded.
     ciKlass* tkls_klass = tkls->klass();
     ciKlass* this_klass = this->klass();
     assert( tkls_klass->is_loaded(), "This class should have been loaded.");
     assert( this_klass->is_loaded(), "This class should have been loaded.");
     // If 'this' type is above the centerline and is a superclass of the
     // other, we can treat 'this' as having the same type as the other.
     if ((above_centerline(this->ptr())) &&
         tkls_klass->is_subtype_of(this_klass)) {
       this_klass = tkls_klass;
     }
     // If 'tinst' type is above the centerline and is a superclass of the
     // other, we can treat 'tinst' as having the same type as the other.
     if ((above_centerline(tkls->ptr())) &&
         this_klass->is_subtype_of(tkls_klass)) {
       tkls_klass = this_klass;
     }
     // Check for classes now being equal
     if (tkls_klass->equals(this_klass)) {
       // If the klasses are equal, the constants may still differ.  Fall to
       // NotNull if they do (neither constant is NULL; that is a special case
       // handled elsewhere).
       if( ptr == Constant ) {
         if (this->_ptr == Constant && tkls->_ptr == Constant &&
             this->klass()->equals(tkls->klass()));
         else if (above_centerline(this->ptr()));
         else if (above_centerline(tkls->ptr()));
         else
           ptr = NotNull;
       }
       return make( ptr, this_klass, off );
     } // Else classes are not equal
     // Since klasses are different, we require the LCA in the Java
     // class hierarchy - which means we have to fall to at least NotNull.
     if( ptr == TopPTR || ptr == AnyNull || ptr == Constant )
       ptr = NotNull;
     // Now we find the LCA of Java classes
     ciKlass* k = this_klass->least_common_ancestor(tkls_klass);
     return   make( ptr, k, off );
   } // End of case KlassPtr
   } // End of switch
   return this;                  // Return the double constant
 }
 //------------------------------xdual------------------------------------------
 // Dual: compute field-by-field dual
 const Type    *TypeKlassPtr::xdual() const {
   return new TypeKlassPtr( dual_ptr(), klass(), dual_offset() );
 }
 //------------------------------get_con----------------------------------------
 intptr_t TypeKlassPtr::get_con() const {
   assert( _ptr == Null || _ptr == Constant, "" );
   assert( _offset >= 0, "" );
   if (_offset != 0) {
     // After being ported to the compiler interface, the compiler no longer
     // directly manipulates the addresses of oops.  Rather, it only has a pointer
     // to a handle at compile time.  This handle is embedded in the generated
     // code and dereferenced at the time the nmethod is made.  Until that time,
     // it is not reasonable to do arithmetic with the addresses of oops (we don't
     // have access to the addresses!).  This does not seem to currently happen,
     // but this assertion here is to help prevent its occurence.
     tty->print_cr("Found oop constant with non-zero offset");
     ShouldNotReachHere();
   }
   return (intptr_t)klass()->constant_encoding();
 }
 //------------------------------dump2------------------------------------------
 // Dump Klass Type
 #ifndef PRODUCT
 void TypeKlassPtr::dump2( Dict & d, uint depth, outputStream *st ) const {
   switch( _ptr ) {
   case Constant:
     st->print("precise ");
   case NotNull:
     {
       const char *name = klass()->name()->as_utf8();
       if( name ) {
         st->print("klass %s: " INTPTR_FORMAT, name, klass());
       } else {
         ShouldNotReachHere();
       }
     }
   case BotPTR:
     if( !WizardMode && !Verbose && !_klass_is_exact ) break;
   case TopPTR:
   case AnyNull:
     st->print(":%s", ptr_msg[_ptr]);
     if( _klass_is_exact ) st->print(":exact");
     break;
   }
   if( _offset ) {               // Dump offset, if any
     if( _offset == OffsetBot )      { st->print("+any"); }
     else if( _offset == OffsetTop ) { st->print("+unknown"); }
     else                            { st->print("+%d", _offset); }
   }
   st->print(" *");
 }
 #endif
 //=============================================================================
 // Convenience common pre-built types.
 //------------------------------make-------------------------------------------
 const TypeFunc *TypeFunc::make( const TypeTuple *domain, const TypeTuple *range ) {
   return (TypeFunc*)(new TypeFunc(domain,range))->hashcons();
 }
 //------------------------------make-------------------------------------------
 const TypeFunc *TypeFunc::make(ciMethod* method) {
   Compile* C = Compile::current();
   const TypeFunc* tf = C->last_tf(method); // check cache
   if (tf != NULL)  return tf;  // The hit rate here is almost 50%.
   const TypeTuple *domain;
   if (method->is_static()) {
     domain = TypeTuple::make_domain(NULL, method->signature());
   } else {
     domain = TypeTuple::make_domain(method->holder(), method->signature());
   }
   const TypeTuple *range  = TypeTuple::make_range(method->signature());
   tf = TypeFunc::make(domain, range);
   C->set_last_tf(method, tf);  // fill cache
   return tf;
 }
 //------------------------------meet-------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
 const Type *TypeFunc::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
   // Current "this->_base" is Func
   switch (t->base()) {          // switch on original type
   case Bottom:                  // Ye Olde Default
     return t;
   default:                      // All else is a mistake
     typerr(t);
   case Top:
     break;
   }
   return this;                  // Return the double constant
 }
 //------------------------------xdual------------------------------------------
 // Dual: compute field-by-field dual
 const Type *TypeFunc::xdual() const {
   return this;
 }
 //------------------------------eq---------------------------------------------
 // Structural equality check for Type representations
 bool TypeFunc::eq( const Type *t ) const {
   const TypeFunc *a = (const TypeFunc*)t;
   return _domain == a->_domain &&
     _range == a->_range;
 }
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
 int TypeFunc::hash(void) const {
   return (intptr_t)_domain + (intptr_t)_range;
 }
 //------------------------------dump2------------------------------------------
 // Dump Function Type
 #ifndef PRODUCT
 void TypeFunc::dump2( Dict &d, uint depth, outputStream *st ) const {
   if( _range->_cnt <= Parms )
     st->print("void");
   else {
     uint i;
     for (i = Parms; i < _range->_cnt-1; i++) {
       _range->field_at(i)->dump2(d,depth,st);
       st->print("/");
     }
     _range->field_at(i)->dump2(d,depth,st);
   }
   st->print(" ");
   st->print("( ");
   if( !depth || d[this] ) {     // Check for recursive dump
     st->print("...)");
     return;
   }
   d.Insert((void*)this,(void*)this);    // Stop recursion
   if (Parms < _domain->_cnt)
     _domain->field_at(Parms)->dump2(d,depth-1,st);
   for (uint i = Parms+1; i < _domain->_cnt; i++) {
     st->print(", ");
     _domain->field_at(i)->dump2(d,depth-1,st);
   }
   st->print(" )");
 }
 #endif
 //------------------------------singleton--------------------------------------
 // TRUE if Type is a singleton type, FALSE otherwise.   Singletons are simple
 // constants (Ldi nodes).  Singletons are integer, float or double constants
 // or a single symbol.
 bool TypeFunc::singleton(void) const {
   return false;                 // Never a singleton
 }
 bool TypeFunc::empty(void) const {
   return false;                 // Never empty
 }
 BasicType TypeFunc::return_type() const{
   if (range()->cnt() == TypeFunc::Parms) {
     return T_VOID;
   }
   return range()->field_at(TypeFunc::Parms)->basic_type();
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/opto/type.cpp@884ed7a10f09 (annotated)

src/share/vm/opto/type.cpp