Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 1997, 2010, 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.

  *

  */

 // This file holds all globally used constants & types, class (forward)

 // declarations and a few frequently used utility functions.

 //----------------------------------------------------------------------------------------------------

 // Constants

 const int LogBytesPerShort   = 1;

 const int LogBytesPerInt     = 2;

 #ifdef _LP64

 const int LogBytesPerWord    = 3;

 #else

 const int LogBytesPerWord    = 2;

 #endif

 const int LogBytesPerLong    = 3;

 const int BytesPerShort      = 1 << LogBytesPerShort;

 const int BytesPerInt        = 1 << LogBytesPerInt;

 const int BytesPerWord       = 1 << LogBytesPerWord;

 const int BytesPerLong       = 1 << LogBytesPerLong;

 const int LogBitsPerByte     = 3;

 const int LogBitsPerShort    = LogBitsPerByte + LogBytesPerShort;

 const int LogBitsPerInt      = LogBitsPerByte + LogBytesPerInt;

 const int LogBitsPerWord     = LogBitsPerByte + LogBytesPerWord;

 const int LogBitsPerLong     = LogBitsPerByte + LogBytesPerLong;

 const int BitsPerByte        = 1 << LogBitsPerByte;

 const int BitsPerShort       = 1 << LogBitsPerShort;

 const int BitsPerInt         = 1 << LogBitsPerInt;

 const int BitsPerWord        = 1 << LogBitsPerWord;

 const int BitsPerLong        = 1 << LogBitsPerLong;

 const int WordAlignmentMask  = (1 << LogBytesPerWord) - 1;

 const int LongAlignmentMask  = (1 << LogBytesPerLong) - 1;

 const int WordsPerLong       = 2;       // Number of stack entries for longs

 const int oopSize            = sizeof(char*); // Full-width oop

 extern int heapOopSize;                       // Oop within a java object

 const int wordSize           = sizeof(char*);

 const int longSize           = sizeof(jlong);

 const int jintSize           = sizeof(jint);

 const int size_tSize         = sizeof(size_t);

 const int BytesPerOop        = BytesPerWord;  // Full-width oop

 extern int LogBytesPerHeapOop;                // Oop within a java object

 extern int LogBitsPerHeapOop;

 extern int BytesPerHeapOop;

 extern int BitsPerHeapOop;

 // Oop encoding heap max

 extern uint64_t OopEncodingHeapMax;

 const int BitsPerJavaInteger = 32;

 const int BitsPerJavaLong    = 64;

 const int BitsPerSize_t      = size_tSize * BitsPerByte;

 // Size of a char[] needed to represent a jint as a string in decimal.

 const int jintAsStringSize = 12;

 // In fact this should be

 // log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);

 // see os::set_memory_serialize_page()

 #ifdef _LP64

 const int SerializePageShiftCount = 4;

 #else

 const int SerializePageShiftCount = 3;

 #endif

 // An opaque struct of heap-word width, so that HeapWord* can be a generic

 // pointer into the heap.  We require that object sizes be measured in

 // units of heap words, so that that

 //   HeapWord* hw;

 //   hw += oop(hw)->foo();

 // works, where foo is a method (like size or scavenge) that returns the

 // object size.

 class HeapWord {

   friend class VMStructs;

  private:

   char* i;

 #ifndef PRODUCT

  public:

   char* value() { return i; }

 #endif

 };

 // HeapWordSize must be 2^LogHeapWordSize.

 const int HeapWordSize        = sizeof(HeapWord);

 #ifdef _LP64

 const int LogHeapWordSize     = 3;

 #else

 const int LogHeapWordSize     = 2;

 #endif

 const int HeapWordsPerLong    = BytesPerLong / HeapWordSize;

 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize;

 // The larger HeapWordSize for 64bit requires larger heaps

 // for the same application running in 64bit.  See bug 4967770.

 // The minimum alignment to a heap word size is done.  Other

 // parts of the memory system may required additional alignment

 // and are responsible for those alignments.

 #ifdef _LP64

 #define ScaleForWordSize(x) align_size_down_((x) * 13 / 10, HeapWordSize)

 #else

 #define ScaleForWordSize(x) (x)

 #endif

 // The minimum number of native machine words necessary to contain "byte_size"

 // bytes.

 inline size_t heap_word_size(size_t byte_size) {

   return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize;

 }

 const size_t K                  = 1024;

 const size_t M                  = K*K;

 const size_t G                  = M*K;

 const size_t HWperKB            = K / sizeof(HeapWord);

 const size_t LOG_K              = 10;

 const size_t LOG_M              = 2 * LOG_K;

 const size_t LOG_G              = 2 * LOG_M;

 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint

 const jint max_jint = (juint)min_jint - 1;                     // 0x7FFFFFFF == largest jint

 // Constants for converting from a base unit to milli-base units.  For

 // example from seconds to milliseconds and microseconds

 const int MILLIUNITS    = 1000;         // milli units per base unit

 const int MICROUNITS    = 1000000;      // micro units per base unit

 const int NANOUNITS     = 1000000000;   // nano units per base unit

 inline const char* proper_unit_for_byte_size(size_t s) {

   if (s >= 10*M) {

     return "M";

   } else if (s >= 10*K) {

     return "K";

   } else {

     return "B";

   }

 }

 inline size_t byte_size_in_proper_unit(size_t s) {

   if (s >= 10*M) {

     return s/M;

   } else if (s >= 10*K) {

     return s/K;

   } else {

     return s;

   }

 }

 //----------------------------------------------------------------------------------------------------

 // VM type definitions

 // intx and uintx are the 'extended' int and 'extended' unsigned int types;

 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.

 typedef intptr_t  intx;

 typedef uintptr_t uintx;

 const intx  min_intx  = (intx)1 << (sizeof(intx)*BitsPerByte-1);

 const intx  max_intx  = (uintx)min_intx - 1;

 const uintx max_uintx = (uintx)-1;

 // Table of values:

 //      sizeof intx         4               8

 // min_intx             0x80000000      0x8000000000000000

 // max_intx             0x7FFFFFFF      0x7FFFFFFFFFFFFFFF

 // max_uintx            0xFFFFFFFF      0xFFFFFFFFFFFFFFFF

 typedef unsigned int uint;   NEEDS_CLEANUP

 //----------------------------------------------------------------------------------------------------

 // Java type definitions

 // All kinds of 'plain' byte addresses

 typedef   signed char s_char;

 typedef unsigned char u_char;

 typedef u_char*       address;

 typedef uintptr_t     address_word; // unsigned integer which will hold a pointer

                                     // except for some implementations of a C++

                                     // linkage pointer to function. Should never

                                     // need one of those to be placed in this

                                     // type anyway.

 //  Utility functions to "portably" (?) bit twiddle pointers

 //  Where portable means keep ANSI C++ compilers quiet

 inline address       set_address_bits(address x, int m)       { return address(intptr_t(x) | m); }

 inline address       clear_address_bits(address x, int m)     { return address(intptr_t(x) & ~m); }

 //  Utility functions to "portably" make cast to/from function pointers.

 inline address_word  mask_address_bits(address x, int m)      { return address_word(x) & m; }

 inline address_word  castable_address(address x)              { return address_word(x) ; }

 inline address_word  castable_address(void* x)                { return address_word(x) ; }

 // Pointer subtraction.

 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have

 // the range we might need to find differences from one end of the heap

 // to the other.

 // A typical use might be:

 //     if (pointer_delta(end(), top()) >= size) {

 //       // enough room for an object of size

 //       ...

 // and then additions like

 //       ... top() + size ...

 // are safe because we know that top() is at least size below end().

 inline size_t pointer_delta(const void* left,

                             const void* right,

                             size_t element_size) {

   return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;

 }

 // A version specialized for HeapWord*'s.

 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {

   return pointer_delta(left, right, sizeof(HeapWord));

 }

 //

 // ANSI C++ does not allow casting from one pointer type to a function pointer

 // directly without at best a warning. This macro accomplishes it silently

 // In every case that is present at this point the value be cast is a pointer

 // to a C linkage function. In somecase the type used for the cast reflects

 // that linkage and a picky compiler would not complain. In other cases because

 // there is no convenient place to place a typedef with extern C linkage (i.e

 // a platform dependent header file) it doesn't. At this point no compiler seems

 // picky enough to catch these instances (which are few). It is possible that

 // using templates could fix these for all cases. This use of templates is likely

 // so far from the middle of the road that it is likely to be problematic in

 // many C++ compilers.

 //

 #define CAST_TO_FN_PTR(func_type, value) ((func_type)(castable_address(value)))

 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((address_word)(func_ptr)))

 // Unsigned byte types for os and stream.hpp

 // Unsigned one, two, four and eigth byte quantities used for describing

 // the .class file format. See JVM book chapter 4.

 typedef jubyte  u1;

 typedef jushort u2;

 typedef juint   u4;

 typedef julong  u8;

 const jubyte  max_jubyte  = (jubyte)-1;  // 0xFF       largest jubyte

 const jushort max_jushort = (jushort)-1; // 0xFFFF     largest jushort

 const juint   max_juint   = (juint)-1;   // 0xFFFFFFFF largest juint

 const julong  max_julong  = (julong)-1;  // 0xFF....FF largest julong

 //----------------------------------------------------------------------------------------------------

 // JVM spec restrictions

 const int max_method_code_size = 64*K - 1;  // JVM spec, 2nd ed. section 4.8.1 (p.134)

 //----------------------------------------------------------------------------------------------------

 // HotSwap - for JVMTI   aka Class File Replacement and PopFrame

 //

 // Determines whether on-the-fly class replacement and frame popping are enabled.

 #define HOTSWAP

 //----------------------------------------------------------------------------------------------------

 // Object alignment, in units of HeapWords.

 //

 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and

 // reference fields can be naturally aligned.

 extern int MinObjAlignment;

 extern int MinObjAlignmentInBytes;

 extern int MinObjAlignmentInBytesMask;

 extern int LogMinObjAlignment;

 extern int LogMinObjAlignmentInBytes;

 // Machine dependent stuff

 #include "incls/_globalDefinitions_pd.hpp.incl"

 // The byte alignment to be used by Arena::Amalloc.  See bugid 4169348.

 // Note: this value must be a power of 2

 #define ARENA_AMALLOC_ALIGNMENT (2*BytesPerWord)

 // Signed variants of alignment helpers.  There are two versions of each, a macro

 // for use in places like enum definitions that require compile-time constant

 // expressions and a function for all other places so as to get type checking.

 #define align_size_up_(size, alignment) (((size) + ((alignment) - 1)) & ~((alignment) - 1))

 inline intptr_t align_size_up(intptr_t size, intptr_t alignment) {

   return align_size_up_(size, alignment);

 }

 #define align_size_down_(size, alignment) ((size) & ~((alignment) - 1))

 inline intptr_t align_size_down(intptr_t size, intptr_t alignment) {

   return align_size_down_(size, alignment);

 }

 // Align objects by rounding up their size, in HeapWord units.

 #define align_object_size_(size) align_size_up_(size, MinObjAlignment)

 inline intptr_t align_object_size(intptr_t size) {

   return align_size_up(size, MinObjAlignment);

 }

 inline bool is_object_aligned(intptr_t addr) {

   return addr == align_object_size(addr);

 }

 // Pad out certain offsets to jlong alignment, in HeapWord units.

 inline intptr_t align_object_offset(intptr_t offset) {

   return align_size_up(offset, HeapWordsPerLong);

 }

 // The expected size in bytes of a cache line, used to pad data structures.

 #define DEFAULT_CACHE_LINE_SIZE 64

 // Bytes needed to pad type to avoid cache-line sharing; alignment should be the

 // expected cache line size (a power of two).  The first addend avoids sharing

 // when the start address is not a multiple of alignment; the second maintains

 // alignment of starting addresses that happen to be a multiple.

 #define PADDING_SIZE(type, alignment)                           \

   ((alignment) + align_size_up_(sizeof(type), alignment))

 // Templates to create a subclass padded to avoid cache line sharing.  These are

 // effective only when applied to derived-most (leaf) classes.

 // When no args are passed to the base ctor.

 template <class T, size_t alignment = DEFAULT_CACHE_LINE_SIZE>

 class Padded: public T {

 private:

   char _pad_buf_[PADDING_SIZE(T, alignment)];

 };

 // When either 0 or 1 args may be passed to the base ctor.

 template <class T, typename Arg1T, size_t alignment = DEFAULT_CACHE_LINE_SIZE>

 class Padded01: public T {

 public:

   Padded01(): T() { }

   Padded01(Arg1T arg1): T(arg1) { }

 private:

   char _pad_buf_[PADDING_SIZE(T, alignment)];

 };

 //----------------------------------------------------------------------------------------------------

 // Utility macros for compilers

 // used to silence compiler warnings

 #define Unused_Variable(var) var

 //----------------------------------------------------------------------------------------------------

 // Miscellaneous

 // 6302670 Eliminate Hotspot __fabsf dependency

 // All fabs() callers should call this function instead, which will implicitly

 // convert the operand to double, avoiding a dependency on __fabsf which

 // doesn't exist in early versions of Solaris 8.

 inline double fabsd(double value) {

   return fabs(value);

 }

 inline jint low (jlong value)                    { return jint(value); }

 inline jint high(jlong value)                    { return jint(value >> 32); }

 // the fancy casts are a hopefully portable way

 // to do unsigned 32 to 64 bit type conversion

 inline void set_low (jlong* value, jint low )    { *value &= (jlong)0xffffffff << 32;

                                                    *value |= (jlong)(julong)(juint)low; }

 inline void set_high(jlong* value, jint high)    { *value &= (jlong)(julong)(juint)0xffffffff;

                                                    *value |= (jlong)high       << 32; }

 inline jlong jlong_from(jint h, jint l) {

   jlong result = 0; // initialization to avoid warning

   set_high(&result, h);

   set_low(&result,  l);

   return result;

 }

 union jlong_accessor {

   jint  words[2];

   jlong long_value;

 };

 void basic_types_init(); // cannot define here; uses assert

 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java

 enum BasicType {

   T_BOOLEAN  =  4,

   T_CHAR     =  5,

   T_FLOAT    =  6,

   T_DOUBLE   =  7,

   T_BYTE     =  8,

   T_SHORT    =  9,

   T_INT      = 10,

   T_LONG     = 11,

   T_OBJECT   = 12,

   T_ARRAY    = 13,

   T_VOID     = 14,

   T_ADDRESS  = 15,

   T_NARROWOOP= 16,

   T_CONFLICT = 17, // for stack value type with conflicting contents

   T_ILLEGAL  = 99

 };

 inline bool is_java_primitive(BasicType t) {

   return T_BOOLEAN <= t && t <= T_LONG;

 }

 inline bool is_subword_type(BasicType t) {

   // these guys are processed exactly like T_INT in calling sequences:

   return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);

 }

 inline bool is_signed_subword_type(BasicType t) {

   return (t == T_BYTE || t == T_SHORT);

 }

 // Convert a char from a classfile signature to a BasicType

 inline BasicType char2type(char c) {

   switch( c ) {

   case 'B': return T_BYTE;

   case 'C': return T_CHAR;

   case 'D': return T_DOUBLE;

   case 'F': return T_FLOAT;

   case 'I': return T_INT;

   case 'J': return T_LONG;

   case 'S': return T_SHORT;

   case 'Z': return T_BOOLEAN;

   case 'V': return T_VOID;

   case 'L': return T_OBJECT;

   case '[': return T_ARRAY;

   }

   return T_ILLEGAL;

 }

 extern char type2char_tab[T_CONFLICT+1];     // Map a BasicType to a jchar

 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }

 extern int type2size[T_CONFLICT+1];         // Map BasicType to result stack elements

 extern const char* type2name_tab[T_CONFLICT+1];     // Map a BasicType to a jchar

 inline const char* type2name(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2name_tab[t] : NULL; }

 extern BasicType name2type(const char* name);

 // Auxilary math routines

 // least common multiple

 extern size_t lcm(size_t a, size_t b);

 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java

 enum BasicTypeSize {

   T_BOOLEAN_size = 1,

   T_CHAR_size    = 1,

   T_FLOAT_size   = 1,

   T_DOUBLE_size  = 2,

   T_BYTE_size    = 1,

   T_SHORT_size   = 1,

   T_INT_size     = 1,

   T_LONG_size    = 2,

   T_OBJECT_size  = 1,

   T_ARRAY_size   = 1,

   T_NARROWOOP_size = 1,

   T_VOID_size    = 0

 };

 // maps a BasicType to its instance field storage type:

 // all sub-word integral types are widened to T_INT

 extern BasicType type2field[T_CONFLICT+1];

 extern BasicType type2wfield[T_CONFLICT+1];

 // size in bytes

 enum ArrayElementSize {

   T_BOOLEAN_aelem_bytes = 1,

   T_CHAR_aelem_bytes    = 2,

   T_FLOAT_aelem_bytes   = 4,

   T_DOUBLE_aelem_bytes  = 8,

   T_BYTE_aelem_bytes    = 1,

   T_SHORT_aelem_bytes   = 2,

   T_INT_aelem_bytes     = 4,

   T_LONG_aelem_bytes    = 8,

 #ifdef _LP64

   T_OBJECT_aelem_bytes  = 8,

   T_ARRAY_aelem_bytes   = 8,

 #else

   T_OBJECT_aelem_bytes  = 4,

   T_ARRAY_aelem_bytes   = 4,

 #endif

   T_NARROWOOP_aelem_bytes = 4,

   T_VOID_aelem_bytes    = 0

 };

 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element

 #ifdef ASSERT

 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts

 #else

 inline int type2aelembytes(BasicType t) { return _type2aelembytes[t]; }

 #endif

 // JavaValue serves as a container for arbitrary Java values.

 class JavaValue {

  public:

   typedef union JavaCallValue {

     jfloat   f;

     jdouble  d;

     jint     i;

     jlong    l;

     jobject  h;

   } JavaCallValue;

  private:

   BasicType _type;

   JavaCallValue _value;

  public:

   JavaValue(BasicType t = T_ILLEGAL) { _type = t; }

   JavaValue(jfloat value) {

     _type    = T_FLOAT;

     _value.f = value;

   }

   JavaValue(jdouble value) {

     _type    = T_DOUBLE;

     _value.d = value;

   }

  jfloat get_jfloat() const { return _value.f; }

  jdouble get_jdouble() const { return _value.d; }

  jint get_jint() const { return _value.i; }

  jlong get_jlong() const { return _value.l; }

  jobject get_jobject() const { return _value.h; }

  JavaCallValue* get_value_addr() { return &_value; }

  BasicType get_type() const { return _type; }

  void set_jfloat(jfloat f) { _value.f = f;}

  void set_jdouble(jdouble d) { _value.d = d;}

  void set_jint(jint i) { _value.i = i;}

  void set_jlong(jlong l) { _value.l = l;}

  void set_jobject(jobject h) { _value.h = h;}

  void set_type(BasicType t) { _type = t; }

  jboolean get_jboolean() const { return (jboolean) (_value.i);}

  jbyte get_jbyte() const { return (jbyte) (_value.i);}

  jchar get_jchar() const { return (jchar) (_value.i);}

  jshort get_jshort() const { return (jshort) (_value.i);}

 };

 #define STACK_BIAS      0

 // V9 Sparc CPU's running in 64 Bit mode use a stack bias of 7ff

 // in order to extend the reach of the stack pointer.

 #if defined(SPARC) && defined(_LP64)

 #undef STACK_BIAS

 #define STACK_BIAS      0x7ff

 #endif

 // TosState describes the top-of-stack state before and after the execution of

 // a bytecode or method. The top-of-stack value may be cached in one or more CPU

 // registers. The TosState corresponds to the 'machine represention' of this cached

 // value. There's 4 states corresponding to the JAVA types int, long, float & double

 // as well as a 5th state in case the top-of-stack value is actually on the top

 // of stack (in memory) and thus not cached. The atos state corresponds to the itos

 // state when it comes to machine representation but is used separately for (oop)

 // type specific operations (e.g. verification code).

 enum TosState {         // describes the tos cache contents

   btos = 0,             // byte, bool tos cached

   ctos = 1,             // char tos cached

   stos = 2,             // short tos cached

   itos = 3,             // int tos cached

   ltos = 4,             // long tos cached

   ftos = 5,             // float tos cached

   dtos = 6,             // double tos cached

   atos = 7,             // object cached

   vtos = 8,             // tos not cached

   number_of_states,

   ilgl                  // illegal state: should not occur

 };

 inline TosState as_TosState(BasicType type) {

   switch (type) {

     case T_BYTE   : return btos;

     case T_BOOLEAN: return btos; // FIXME: Add ztos

     case T_CHAR   : return ctos;

     case T_SHORT  : return stos;

     case T_INT    : return itos;

     case T_LONG   : return ltos;

     case T_FLOAT  : return ftos;

     case T_DOUBLE : return dtos;

     case T_VOID   : return vtos;

     case T_ARRAY  : // fall through

     case T_OBJECT : return atos;

   }

   return ilgl;

 }

 inline BasicType as_BasicType(TosState state) {

   switch (state) {

     //case ztos: return T_BOOLEAN;//FIXME

     case btos : return T_BYTE;

     case ctos : return T_CHAR;

     case stos : return T_SHORT;

     case itos : return T_INT;

     case ltos : return T_LONG;

     case ftos : return T_FLOAT;

     case dtos : return T_DOUBLE;

     case atos : return T_OBJECT;

     case vtos : return T_VOID;

   }

   return T_ILLEGAL;

 }

 // Helper function to convert BasicType info into TosState

 // Note: Cannot define here as it uses global constant at the time being.

 TosState as_TosState(BasicType type);

 // ReferenceType is used to distinguish between java/lang/ref/Reference subclasses

 enum ReferenceType {

  REF_NONE,      // Regular class

  REF_OTHER,     // Subclass of java/lang/ref/Reference, but not subclass of one of the classes below

  REF_SOFT,      // Subclass of java/lang/ref/SoftReference

  REF_WEAK,      // Subclass of java/lang/ref/WeakReference

  REF_FINAL,     // Subclass of java/lang/ref/FinalReference

  REF_PHANTOM    // Subclass of java/lang/ref/PhantomReference

 };

 // JavaThreadState keeps track of which part of the code a thread is executing in. This

 // information is needed by the safepoint code.

 //

 // There are 4 essential states:

 //

 //  _thread_new         : Just started, but not executed init. code yet (most likely still in OS init code)

 //  _thread_in_native   : In native code. This is a safepoint region, since all oops will be in jobject handles

 //  _thread_in_vm       : Executing in the vm

 //  _thread_in_Java     : Executing either interpreted or compiled Java code (or could be in a stub)

 //

 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in

 // a transition from one state to another. These extra states makes it possible for the safepoint code to

 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.

 //

 // Given a state, the xxx_trans state can always be found by adding 1.

 //

 enum JavaThreadState {

   _thread_uninitialized     =  0, // should never happen (missing initialization)

   _thread_new               =  2, // just starting up, i.e., in process of being initialized

   _thread_new_trans         =  3, // corresponding transition state (not used, included for completness)

   _thread_in_native         =  4, // running in native code

   _thread_in_native_trans   =  5, // corresponding transition state

   _thread_in_vm             =  6, // running in VM

   _thread_in_vm_trans       =  7, // corresponding transition state

   _thread_in_Java           =  8, // running in Java or in stub code

   _thread_in_Java_trans     =  9, // corresponding transition state (not used, included for completness)

   _thread_blocked           = 10, // blocked in vm

   _thread_blocked_trans     = 11, // corresponding transition state

   _thread_max_state         = 12  // maximum thread state+1 - used for statistics allocation

 };

 // Handy constants for deciding which compiler mode to use.

 enum MethodCompilation {

   InvocationEntryBci = -1,     // i.e., not a on-stack replacement compilation

   InvalidOSREntryBci = -2

 };

 // Enumeration to distinguish tiers of compilation

 enum CompLevel {

   CompLevel_none              = 0,

   CompLevel_fast_compile      = 1,

   CompLevel_full_optimization = 2,

   CompLevel_highest_tier      = CompLevel_full_optimization,

 #ifdef TIERED

   CompLevel_initial_compile   = CompLevel_fast_compile

 #else

   CompLevel_initial_compile   = CompLevel_full_optimization

 #endif // TIERED

 };

 inline bool is_tier1_compile(int comp_level) {

   return comp_level == CompLevel_fast_compile;

 }

 inline bool is_tier2_compile(int comp_level) {

   return comp_level == CompLevel_full_optimization;

 }

 inline bool is_highest_tier_compile(int comp_level) {

   return comp_level == CompLevel_highest_tier;

 }

 //----------------------------------------------------------------------------------------------------

 // 'Forward' declarations of frequently used classes

 // (in order to reduce interface dependencies & reduce

 // number of unnecessary compilations after changes)

 class symbolTable;

 class ClassFileStream;

 class Event;

 class Thread;

 class  VMThread;

 class  JavaThread;

 class Threads;

 class VM_Operation;

 class VMOperationQueue;

 class CodeBlob;

 class  nmethod;

 class  OSRAdapter;

 class  I2CAdapter;

 class  C2IAdapter;

 class CompiledIC;

 class relocInfo;

 class ScopeDesc;

 class PcDesc;

 class Recompiler;

 class Recompilee;

 class RecompilationPolicy;

 class RFrame;

 class  CompiledRFrame;

 class  InterpretedRFrame;

 class frame;

 class vframe;

 class   javaVFrame;

 class     interpretedVFrame;

 class     compiledVFrame;

 class     deoptimizedVFrame;

 class   externalVFrame;

 class     entryVFrame;

 class RegisterMap;

 class Mutex;

 class Monitor;

 class BasicLock;

 class BasicObjectLock;

 class PeriodicTask;

 class JavaCallWrapper;

 class   oopDesc;

 class NativeCall;

 class zone;

 class StubQueue;

 class outputStream;

 class ResourceArea;

 class DebugInformationRecorder;

 class ScopeValue;

 class CompressedStream;

 class   DebugInfoReadStream;

 class   DebugInfoWriteStream;

 class LocationValue;

 class ConstantValue;

 class IllegalValue;

 class PrivilegedElement;

 class MonitorArray;

 class MonitorInfo;

 class OffsetClosure;

 class OopMapCache;

 class InterpreterOopMap;

 class OopMapCacheEntry;

 class OSThread;

 typedef int (*OSThreadStartFunc)(void*);

 class Space;

 class JavaValue;

 class methodHandle;

 class JavaCallArguments;

 // Basic support for errors (general debug facilities not defined at this point fo the include phase)

 extern void basic_fatal(const char* msg);

 //----------------------------------------------------------------------------------------------------

 // Special constants for debugging

 const jint     badInt           = -3;                       // generic "bad int" value

 const long     badAddressVal    = -2;                       // generic "bad address" value

 const long     badOopVal        = -1;                       // generic "bad oop" value

 const intptr_t badHeapOopVal    = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC

 const int      badHandleValue   = 0xBC;                     // value used to zap vm handle area

 const int      badResourceValue = 0xAB;                     // value used to zap resource area

 const int      freeBlockPad     = 0xBA;                     // value used to pad freed blocks.

 const int      uninitBlockPad   = 0xF1;                     // value used to zap newly malloc'd blocks.

 const intptr_t badJNIHandleVal  = (intptr_t) CONST64(0xFEFEFEFEFEFEFEFE); // value used to zap jni handle area

 const juint    badHeapWordVal   = 0xBAADBABE;               // value used to zap heap after GC

 const int      badCodeHeapNewVal= 0xCC;                     // value used to zap Code heap at allocation

 const int      badCodeHeapFreeVal = 0xDD;                   // value used to zap Code heap at deallocation

 // (These must be implemented as #defines because C++ compilers are

 // not obligated to inline non-integral constants!)

 #define       badAddress        ((address)::badAddressVal)

 #define       badOop            ((oop)::badOopVal)

 #define       badHeapWord       (::badHeapWordVal)

 #define       badJNIHandle      ((oop)::badJNIHandleVal)

 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)

 #define TASKQUEUE_SIZE (NOT_LP64(1<<14) LP64_ONLY(1<<17))

 //----------------------------------------------------------------------------------------------------

 // Utility functions for bitfield manipulations

 const intptr_t AllBits    = ~0; // all bits set in a word

 const intptr_t NoBits     =  0; // no bits set in a word

 const jlong    NoLongBits =  0; // no bits set in a long

 const intptr_t OneBit     =  1; // only right_most bit set in a word

 // get a word with the n.th or the right-most or left-most n bits set

 // (note: #define used only so that they can be used in enum constant definitions)

 #define nth_bit(n)        (n >= BitsPerWord ? 0 : OneBit << (n))

 #define right_n_bits(n)   (nth_bit(n) - 1)

 #define left_n_bits(n)    (right_n_bits(n) << (n >= BitsPerWord ? 0 : (BitsPerWord - n)))

 // bit-operations using a mask m

 inline void   set_bits    (intptr_t& x, intptr_t m) { x |= m; }

 inline void clear_bits    (intptr_t& x, intptr_t m) { x &= ~m; }

 inline intptr_t mask_bits      (intptr_t  x, intptr_t m) { return x & m; }

 inline jlong    mask_long_bits (jlong     x, jlong    m) { return x & m; }

 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }

 // bit-operations using the n.th bit

 inline void    set_nth_bit(intptr_t& x, int n) { set_bits  (x, nth_bit(n)); }

 inline void  clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }

 inline bool is_set_nth_bit(intptr_t  x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }

 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)

 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {

   return mask_bits(x >> start_bit_no, right_n_bits(field_length));

 }

 //----------------------------------------------------------------------------------------------------

 // Utility functions for integers

 // Avoid use of global min/max macros which may cause unwanted double

 // evaluation of arguments.

 #ifdef max

 #undef max

 #endif

 #ifdef min

 #undef min

 #endif

 #define max(a,b) Do_not_use_max_use_MAX2_instead

 #define min(a,b) Do_not_use_min_use_MIN2_instead

 // It is necessary to use templates here. Having normal overloaded

 // functions does not work because it is necessary to provide both 32-

 // and 64-bit overloaded functions, which does not work, and having

 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)

 // will be even more error-prone than macros.

 template<class T> inline T MAX2(T a, T b)           { return (a > b) ? a : b; }

 template<class T> inline T MIN2(T a, T b)           { return (a < b) ? a : b; }

 template<class T> inline T MAX3(T a, T b, T c)      { return MAX2(MAX2(a, b), c); }

 template<class T> inline T MIN3(T a, T b, T c)      { return MIN2(MIN2(a, b), c); }

 template<class T> inline T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }

 template<class T> inline T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }

 template<class T> inline T ABS(T x)                 { return (x > 0) ? x : -x; }

 // true if x is a power of 2, false otherwise

 inline bool is_power_of_2(intptr_t x) {

   return ((x != NoBits) && (mask_bits(x, x - 1) == NoBits));

 }

 // long version of is_power_of_2

 inline bool is_power_of_2_long(jlong x) {

   return ((x != NoLongBits) && (mask_long_bits(x, x - 1) == NoLongBits));

 }

 //* largest i such that 2^i <= x

 //  A negative value of 'x' will return '31'

 inline int log2_intptr(intptr_t x) {

   int i = -1;

   uintptr_t p =  1;

   while (p != 0 && p <= (uintptr_t)x) {

     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)

     i++; p *= 2;

   }

   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))

   // (if p = 0 then overflow occurred and i = 31)

   return i;

 }

 //* largest i such that 2^i <= x

 //  A negative value of 'x' will return '63'

 inline int log2_long(jlong x) {

   int i = -1;

   julong p =  1;

   while (p != 0 && p <= (julong)x) {

     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)

     i++; p *= 2;

   }

   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))

   // (if p = 0 then overflow occurred and i = 63)

   return i;

 }

 //* the argument must be exactly a power of 2

 inline int exact_log2(intptr_t x) {

   #ifdef ASSERT

     if (!is_power_of_2(x)) basic_fatal("x must be a power of 2");

   #endif

   return log2_intptr(x);

 }

 //* the argument must be exactly a power of 2

 inline int exact_log2_long(jlong x) {

   #ifdef ASSERT

     if (!is_power_of_2_long(x)) basic_fatal("x must be a power of 2");

   #endif

   return log2_long(x);

 }

 // returns integer round-up to the nearest multiple of s (s must be a power of two)

 inline intptr_t round_to(intptr_t x, uintx s) {

   #ifdef ASSERT

     if (!is_power_of_2(s)) basic_fatal("s must be a power of 2");

   #endif

   const uintx m = s - 1;

   return mask_bits(x + m, ~m);

 }

 // returns integer round-down to the nearest multiple of s (s must be a power of two)

 inline intptr_t round_down(intptr_t x, uintx s) {

   #ifdef ASSERT

     if (!is_power_of_2(s)) basic_fatal("s must be a power of 2");

   #endif

   const uintx m = s - 1;

   return mask_bits(x, ~m);

 }

 inline bool is_odd (intx x) { return x & 1;      }

 inline bool is_even(intx x) { return !is_odd(x); }

 // "to" should be greater than "from."

 inline intx byte_size(void* from, void* to) {

   return (address)to - (address)from;

 }

 //----------------------------------------------------------------------------------------------------

 // Avoid non-portable casts with these routines (DEPRECATED)

 // NOTE: USE Bytes class INSTEAD WHERE POSSIBLE

 //       Bytes is optimized machine-specifically and may be much faster then the portable routines below.

 // Given sequence of four bytes, build into a 32-bit word

 // following the conventions used in class files.

 // On the 386, this could be realized with a simple address cast.

 //

 // This routine takes eight bytes:

 inline u8 build_u8_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {

   return  ( u8(c1) << 56 )  &  ( u8(0xff) << 56 )

        |  ( u8(c2) << 48 )  &  ( u8(0xff) << 48 )

        |  ( u8(c3) << 40 )  &  ( u8(0xff) << 40 )

        |  ( u8(c4) << 32 )  &  ( u8(0xff) << 32 )

        |  ( u8(c5) << 24 )  &  ( u8(0xff) << 24 )

        |  ( u8(c6) << 16 )  &  ( u8(0xff) << 16 )

        |  ( u8(c7) <<  8 )  &  ( u8(0xff) <<  8 )

        |  ( u8(c8) <<  0 )  &  ( u8(0xff) <<  0 );

 }

 // This routine takes four bytes:

 inline u4 build_u4_from( u1 c1, u1 c2, u1 c3, u1 c4 ) {

   return  ( u4(c1) << 24 )  &  0xff000000

        |  ( u4(c2) << 16 )  &  0x00ff0000

        |  ( u4(c3) <<  8 )  &  0x0000ff00

        |  ( u4(c4) <<  0 )  &  0x000000ff;

 }

 // And this one works if the four bytes are contiguous in memory:

 inline u4 build_u4_from( u1* p ) {

   return  build_u4_from( p[0], p[1], p[2], p[3] );

 }

 // Ditto for two-byte ints:

 inline u2 build_u2_from( u1 c1, u1 c2 ) {

   return  u2(( u2(c1) <<  8 )  &  0xff00

           |  ( u2(c2) <<  0 )  &  0x00ff);

 }

 // And this one works if the two bytes are contiguous in memory:

 inline u2 build_u2_from( u1* p ) {

   return  build_u2_from( p[0], p[1] );

 }

 // Ditto for floats:

 inline jfloat build_float_from( u1 c1, u1 c2, u1 c3, u1 c4 ) {

   u4 u = build_u4_from( c1, c2, c3, c4 );

   return  *(jfloat*)&u;

 }

 inline jfloat build_float_from( u1* p ) {

   u4 u = build_u4_from( p );

   return  *(jfloat*)&u;

 }

 // now (64-bit) longs

 inline jlong build_long_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {

   return  ( jlong(c1) << 56 )  &  ( jlong(0xff) << 56 )

        |  ( jlong(c2) << 48 )  &  ( jlong(0xff) << 48 )

        |  ( jlong(c3) << 40 )  &  ( jlong(0xff) << 40 )

        |  ( jlong(c4) << 32 )  &  ( jlong(0xff) << 32 )

        |  ( jlong(c5) << 24 )  &  ( jlong(0xff) << 24 )

        |  ( jlong(c6) << 16 )  &  ( jlong(0xff) << 16 )

        |  ( jlong(c7) <<  8 )  &  ( jlong(0xff) <<  8 )

        |  ( jlong(c8) <<  0 )  &  ( jlong(0xff) <<  0 );

 }

 inline jlong build_long_from( u1* p ) {

   return  build_long_from( p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7] );

 }

 // Doubles, too!

 inline jdouble build_double_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {

   jlong u = build_long_from( c1, c2, c3, c4, c5, c6, c7, c8 );

   return  *(jdouble*)&u;

 }

 inline jdouble build_double_from( u1* p ) {

   jlong u = build_long_from( p );

   return  *(jdouble*)&u;

 }

 // Portable routines to go the other way:

 inline void explode_short_to( u2 x, u1& c1, u1& c2 ) {

   c1 = u1(x >> 8);

   c2 = u1(x);

 }

 inline void explode_short_to( u2 x, u1* p ) {

   explode_short_to( x, p[0], p[1]);

 }

 inline void explode_int_to( u4 x, u1& c1, u1& c2, u1& c3, u1& c4 ) {

   c1 = u1(x >> 24);

   c2 = u1(x >> 16);

   c3 = u1(x >>  8);

   c4 = u1(x);

 }

 inline void explode_int_to( u4 x, u1* p ) {

   explode_int_to( x, p[0], p[1], p[2], p[3]);

 }

 // Pack and extract shorts to/from ints:

 inline int extract_low_short_from_int(jint x) {

   return x & 0xffff;

 }

 inline int extract_high_short_from_int(jint x) {

   return (x >> 16) & 0xffff;

 }

 inline int build_int_from_shorts( jushort low, jushort high ) {

   return ((int)((unsigned int)high << 16) | (unsigned int)low);

 }

 // Printf-style formatters for fixed- and variable-width types as pointers and

 // integers.

 //

 // Each compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp)

 // must define the macro FORMAT64_MODIFIER, which is the modifier for '%x' or

 // '%d' formats to indicate a 64-bit quantity; commonly "l" (in LP64) or "ll"

 // (in ILP32).

 // Format 32-bit quantities.

 #define INT32_FORMAT  "%d"

 #define UINT32_FORMAT "%u"

 #define INT32_FORMAT_W(width)   "%" #width "d"

 #define UINT32_FORMAT_W(width)  "%" #width "u"

 #define PTR32_FORMAT  "0x%08x"

 // Format 64-bit quantities.

 #define INT64_FORMAT  "%" FORMAT64_MODIFIER "d"

 #define UINT64_FORMAT "%" FORMAT64_MODIFIER "u"

 #define PTR64_FORMAT  "0x%016" FORMAT64_MODIFIER "x"

 #define INT64_FORMAT_W(width)  "%" #width FORMAT64_MODIFIER "d"

 #define UINT64_FORMAT_W(width) "%" #width FORMAT64_MODIFIER "u"

 // Format macros that allow the field width to be specified.  The width must be

 // a string literal (e.g., "8") or a macro that evaluates to one.

 #ifdef _LP64

 #define UINTX_FORMAT_W(width)   UINT64_FORMAT_W(width)

 #define SSIZE_FORMAT_W(width)   INT64_FORMAT_W(width)

 #define SIZE_FORMAT_W(width)    UINT64_FORMAT_W(width)

 #else

 #define UINTX_FORMAT_W(width)   UINT32_FORMAT_W(width)

 #define SSIZE_FORMAT_W(width)   INT32_FORMAT_W(width)

 #define SIZE_FORMAT_W(width)    UINT32_FORMAT_W(width)

 #endif // _LP64

 // Format pointers and size_t (or size_t-like integer types) which change size

 // between 32- and 64-bit. The pointer format theoretically should be "%p",

 // however, it has different output on different platforms. On Windows, the data

 // will be padded with zeros automatically. On Solaris, we can use "%016p" &

 // "%08p" on 64 bit & 32 bit platforms to make the data padded with extra zeros.

 // On Linux, "%016p" or "%08p" is not be allowed, at least on the latest GCC

 // 4.3.2. So we have to use "%016x" or "%08x" to simulate the printing format.

 // GCC 4.3.2, however requires the data to be converted to "intptr_t" when

 // using "%x".

 #ifdef  _LP64

 #define PTR_FORMAT    PTR64_FORMAT

 #define UINTX_FORMAT  UINT64_FORMAT

 #define INTX_FORMAT   INT64_FORMAT

 #define SIZE_FORMAT   UINT64_FORMAT

 #define SSIZE_FORMAT  INT64_FORMAT

 #else   // !_LP64

 #define PTR_FORMAT    PTR32_FORMAT

 #define UINTX_FORMAT  UINT32_FORMAT

 #define INTX_FORMAT   INT32_FORMAT

 #define SIZE_FORMAT   UINT32_FORMAT

 #define SSIZE_FORMAT  INT32_FORMAT

 #endif  // _LP64

 #define INTPTR_FORMAT PTR_FORMAT

 // Enable zap-a-lot if in debug version.

 # ifdef ASSERT

 # ifdef COMPILER2

 #   define ENABLE_ZAP_DEAD_LOCALS

 #endif /* COMPILER2 */

 # endif /* ASSERT */

 #define ARRAY_SIZE(array) (sizeof(array)/sizeof((array)[0]))