1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_UTILITIES_GLOBALDEFINITIONS_HPP
  26 #define SHARE_VM_UTILITIES_GLOBALDEFINITIONS_HPP
  27 
  28 #include "utilities/compilerWarnings.hpp"
  29 #include "utilities/debug.hpp"
  30 #include "utilities/macros.hpp"
  31 
  32 #include COMPILER_HEADER(utilities/globalDefinitions)
  33 
  34 // Defaults for macros that might be defined per compiler.
  35 #ifndef NOINLINE
  36 #define NOINLINE
  37 #endif
  38 #ifndef ALWAYSINLINE
  39 #define ALWAYSINLINE inline
  40 #endif
  41 
  42 // This file holds all globally used constants & types, class (forward)
  43 // declarations and a few frequently used utility functions.
  44 
  45 //----------------------------------------------------------------------------------------------------
  46 // Printf-style formatters for fixed- and variable-width types as pointers and
  47 // integers.  These are derived from the definitions in inttypes.h.  If the platform
  48 // doesn't provide appropriate definitions, they should be provided in
  49 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp)
  50 
  51 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false")
  52 
  53 // Format 32-bit quantities.
  54 #define INT32_FORMAT           "%" PRId32
  55 #define UINT32_FORMAT          "%" PRIu32
  56 #define INT32_FORMAT_W(width)  "%" #width PRId32
  57 #define UINT32_FORMAT_W(width) "%" #width PRIu32
  58 
  59 #define PTR32_FORMAT           "0x%08" PRIx32
  60 #define PTR32_FORMAT_W(width)  "0x%" #width PRIx32
  61 
  62 // Format 64-bit quantities.
  63 #define INT64_FORMAT           "%" PRId64
  64 #define UINT64_FORMAT          "%" PRIu64
  65 #define UINT64_FORMAT_X        "%" PRIx64
  66 #define INT64_FORMAT_W(width)  "%" #width PRId64
  67 #define UINT64_FORMAT_W(width) "%" #width PRIu64
  68 
  69 #define PTR64_FORMAT           "0x%016" PRIx64
  70 
  71 // Format jlong, if necessary
  72 #ifndef JLONG_FORMAT
  73 #define JLONG_FORMAT           INT64_FORMAT
  74 #endif
  75 #ifndef JULONG_FORMAT
  76 #define JULONG_FORMAT          UINT64_FORMAT
  77 #endif
  78 #ifndef JULONG_FORMAT_X
  79 #define JULONG_FORMAT_X        UINT64_FORMAT_X
  80 #endif
  81 
  82 // Format pointers which change size between 32- and 64-bit.
  83 #ifdef  _LP64
  84 #define INTPTR_FORMAT "0x%016" PRIxPTR
  85 #define PTR_FORMAT    "0x%016" PRIxPTR
  86 #else   // !_LP64
  87 #define INTPTR_FORMAT "0x%08"  PRIxPTR
  88 #define PTR_FORMAT    "0x%08"  PRIxPTR
  89 #endif  // _LP64
  90 
  91 // Format pointers without leading zeros
  92 #define INTPTRNZ_FORMAT "0x%"  PRIxPTR
  93 
  94 #define INTPTR_FORMAT_W(width)   "%" #width PRIxPTR
  95 
  96 #define SSIZE_FORMAT             "%"   PRIdPTR
  97 #define SIZE_FORMAT              "%"   PRIuPTR
  98 #define SIZE_FORMAT_HEX          "0x%" PRIxPTR
  99 #define SSIZE_FORMAT_W(width)    "%"   #width PRIdPTR
 100 #define SIZE_FORMAT_W(width)     "%"   #width PRIuPTR
 101 #define SIZE_FORMAT_HEX_W(width) "0x%" #width PRIxPTR
 102 
 103 #define INTX_FORMAT           "%" PRIdPTR
 104 #define UINTX_FORMAT          "%" PRIuPTR
 105 #define INTX_FORMAT_W(width)  "%" #width PRIdPTR
 106 #define UINTX_FORMAT_W(width) "%" #width PRIuPTR
 107 
 108 //----------------------------------------------------------------------------------------------------
 109 // Constants
 110 
 111 const int LogBytesPerShort   = 1;
 112 const int LogBytesPerInt     = 2;
 113 #ifdef _LP64
 114 const int LogBytesPerWord    = 3;
 115 #else
 116 const int LogBytesPerWord    = 2;
 117 #endif
 118 const int LogBytesPerLong    = 3;
 119 
 120 const int BytesPerShort      = 1 << LogBytesPerShort;
 121 const int BytesPerInt        = 1 << LogBytesPerInt;
 122 const int BytesPerWord       = 1 << LogBytesPerWord;
 123 const int BytesPerLong       = 1 << LogBytesPerLong;
 124 
 125 const int LogBitsPerByte     = 3;
 126 const int LogBitsPerShort    = LogBitsPerByte + LogBytesPerShort;
 127 const int LogBitsPerInt      = LogBitsPerByte + LogBytesPerInt;
 128 const int LogBitsPerWord     = LogBitsPerByte + LogBytesPerWord;
 129 const int LogBitsPerLong     = LogBitsPerByte + LogBytesPerLong;
 130 
 131 const int BitsPerByte        = 1 << LogBitsPerByte;
 132 const int BitsPerShort       = 1 << LogBitsPerShort;
 133 const int BitsPerInt         = 1 << LogBitsPerInt;
 134 const int BitsPerWord        = 1 << LogBitsPerWord;
 135 const int BitsPerLong        = 1 << LogBitsPerLong;
 136 
 137 const int WordAlignmentMask  = (1 << LogBytesPerWord) - 1;
 138 const int LongAlignmentMask  = (1 << LogBytesPerLong) - 1;
 139 
 140 const int WordsPerLong       = 2;       // Number of stack entries for longs
 141 
 142 const int oopSize            = sizeof(char*); // Full-width oop
 143 extern int heapOopSize;                       // Oop within a java object
 144 const int wordSize           = sizeof(char*);
 145 const int longSize           = sizeof(jlong);
 146 const int jintSize           = sizeof(jint);
 147 const int size_tSize         = sizeof(size_t);
 148 
 149 const int BytesPerOop        = BytesPerWord;  // Full-width oop
 150 
 151 extern int LogBytesPerHeapOop;                // Oop within a java object
 152 extern int LogBitsPerHeapOop;
 153 extern int BytesPerHeapOop;
 154 extern int BitsPerHeapOop;
 155 
 156 const int BitsPerJavaInteger = 32;
 157 const int BitsPerJavaLong    = 64;
 158 const int BitsPerSize_t      = size_tSize * BitsPerByte;
 159 
 160 // Size of a char[] needed to represent a jint as a string in decimal.
 161 const int jintAsStringSize = 12;
 162 
 163 // In fact this should be
 164 // log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
 165 // see os::set_memory_serialize_page()
 166 #ifdef _LP64
 167 const int SerializePageShiftCount = 4;
 168 #else
 169 const int SerializePageShiftCount = 3;
 170 #endif
 171 
 172 // An opaque struct of heap-word width, so that HeapWord* can be a generic
 173 // pointer into the heap.  We require that object sizes be measured in
 174 // units of heap words, so that that
 175 //   HeapWord* hw;
 176 //   hw += oop(hw)->foo();
 177 // works, where foo is a method (like size or scavenge) that returns the
 178 // object size.
 179 class HeapWord {
 180   friend class VMStructs;
 181  private:
 182   char* i;
 183 #ifndef PRODUCT
 184  public:
 185   char* value() { return i; }
 186 #endif
 187 };
 188 
 189 // Analogous opaque struct for metadata allocated from
 190 // metaspaces.
 191 class MetaWord {
 192  private:
 193   char* i;
 194 };
 195 
 196 // HeapWordSize must be 2^LogHeapWordSize.
 197 const int HeapWordSize        = sizeof(HeapWord);
 198 #ifdef _LP64
 199 const int LogHeapWordSize     = 3;
 200 #else
 201 const int LogHeapWordSize     = 2;
 202 #endif
 203 const int HeapWordsPerLong    = BytesPerLong / HeapWordSize;
 204 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize;
 205 
 206 // The minimum number of native machine words necessary to contain "byte_size"
 207 // bytes.
 208 inline size_t heap_word_size(size_t byte_size) {
 209   return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize;
 210 }
 211 
 212 //-------------------------------------------
 213 // Constant for jlong (standardized by C++11)
 214 
 215 // Build a 64bit integer constant
 216 #define CONST64(x)  (x ## LL)
 217 #define UCONST64(x) (x ## ULL)
 218 
 219 const jlong min_jlong = CONST64(0x8000000000000000);
 220 const jlong max_jlong = CONST64(0x7fffffffffffffff);
 221 
 222 const size_t K                  = 1024;
 223 const size_t M                  = K*K;
 224 const size_t G                  = M*K;
 225 const size_t HWperKB            = K / sizeof(HeapWord);
 226 
 227 // Constants for converting from a base unit to milli-base units.  For
 228 // example from seconds to milliseconds and microseconds
 229 
 230 const int MILLIUNITS    = 1000;         // milli units per base unit
 231 const int MICROUNITS    = 1000000;      // micro units per base unit
 232 const int NANOUNITS     = 1000000000;   // nano units per base unit
 233 
 234 const jlong NANOSECS_PER_SEC      = CONST64(1000000000);
 235 const jint  NANOSECS_PER_MILLISEC = 1000000;
 236 
 237 inline const char* proper_unit_for_byte_size(size_t s) {
 238 #ifdef _LP64
 239   if (s >= 10*G) {
 240     return "G";
 241   }
 242 #endif
 243   if (s >= 10*M) {
 244     return "M";
 245   } else if (s >= 10*K) {
 246     return "K";
 247   } else {
 248     return "B";
 249   }
 250 }
 251 
 252 template <class T>
 253 inline T byte_size_in_proper_unit(T s) {
 254 #ifdef _LP64
 255   if (s >= 10*G) {
 256     return (T)(s/G);
 257   }
 258 #endif
 259   if (s >= 10*M) {
 260     return (T)(s/M);
 261   } else if (s >= 10*K) {
 262     return (T)(s/K);
 263   } else {
 264     return s;
 265   }
 266 }
 267 
 268 inline const char* exact_unit_for_byte_size(size_t s) {
 269 #ifdef _LP64
 270   if (s >= G && (s % G) == 0) {
 271     return "G";
 272   }
 273 #endif
 274   if (s >= M && (s % M) == 0) {
 275     return "M";
 276   }
 277   if (s >= K && (s % K) == 0) {
 278     return "K";
 279   }
 280   return "B";
 281 }
 282 
 283 inline size_t byte_size_in_exact_unit(size_t s) {
 284 #ifdef _LP64
 285   if (s >= G && (s % G) == 0) {
 286     return s / G;
 287   }
 288 #endif
 289   if (s >= M && (s % M) == 0) {
 290     return s / M;
 291   }
 292   if (s >= K && (s % K) == 0) {
 293     return s / K;
 294   }
 295   return s;
 296 }
 297 
 298 //----------------------------------------------------------------------------------------------------
 299 // VM type definitions
 300 
 301 // intx and uintx are the 'extended' int and 'extended' unsigned int types;
 302 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.
 303 
 304 typedef intptr_t  intx;
 305 typedef uintptr_t uintx;
 306 
 307 const intx  min_intx  = (intx)1 << (sizeof(intx)*BitsPerByte-1);
 308 const intx  max_intx  = (uintx)min_intx - 1;
 309 const uintx max_uintx = (uintx)-1;
 310 
 311 // Table of values:
 312 //      sizeof intx         4               8
 313 // min_intx             0x80000000      0x8000000000000000
 314 // max_intx             0x7FFFFFFF      0x7FFFFFFFFFFFFFFF
 315 // max_uintx            0xFFFFFFFF      0xFFFFFFFFFFFFFFFF
 316 
 317 typedef unsigned int uint;   NEEDS_CLEANUP
 318 
 319 
 320 //----------------------------------------------------------------------------------------------------
 321 // Java type definitions
 322 
 323 // All kinds of 'plain' byte addresses
 324 typedef   signed char s_char;
 325 typedef unsigned char u_char;
 326 typedef u_char*       address;
 327 typedef uintptr_t     address_word; // unsigned integer which will hold a pointer
 328                                     // except for some implementations of a C++
 329                                     // linkage pointer to function. Should never
 330                                     // need one of those to be placed in this
 331                                     // type anyway.
 332 
 333 //  Utility functions to "portably" (?) bit twiddle pointers
 334 //  Where portable means keep ANSI C++ compilers quiet
 335 
 336 inline address       set_address_bits(address x, int m)       { return address(intptr_t(x) | m); }
 337 inline address       clear_address_bits(address x, int m)     { return address(intptr_t(x) & ~m); }
 338 
 339 //  Utility functions to "portably" make cast to/from function pointers.
 340 
 341 inline address_word  mask_address_bits(address x, int m)      { return address_word(x) & m; }
 342 inline address_word  castable_address(address x)              { return address_word(x) ; }
 343 inline address_word  castable_address(void* x)                { return address_word(x) ; }
 344 
 345 // Pointer subtraction.
 346 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have
 347 // the range we might need to find differences from one end of the heap
 348 // to the other.
 349 // A typical use might be:
 350 //     if (pointer_delta(end(), top()) >= size) {
 351 //       // enough room for an object of size
 352 //       ...
 353 // and then additions like
 354 //       ... top() + size ...
 355 // are safe because we know that top() is at least size below end().
 356 inline size_t pointer_delta(const volatile void* left,
 357                             const volatile void* right,
 358                             size_t element_size) {
 359   return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;
 360 }
 361 
 362 // A version specialized for HeapWord*'s.
 363 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {
 364   return pointer_delta(left, right, sizeof(HeapWord));
 365 }
 366 // A version specialized for MetaWord*'s.
 367 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) {
 368   return pointer_delta(left, right, sizeof(MetaWord));
 369 }
 370 
 371 //
 372 // ANSI C++ does not allow casting from one pointer type to a function pointer
 373 // directly without at best a warning. This macro accomplishes it silently
 374 // In every case that is present at this point the value be cast is a pointer
 375 // to a C linkage function. In some case the type used for the cast reflects
 376 // that linkage and a picky compiler would not complain. In other cases because
 377 // there is no convenient place to place a typedef with extern C linkage (i.e
 378 // a platform dependent header file) it doesn't. At this point no compiler seems
 379 // picky enough to catch these instances (which are few). It is possible that
 380 // using templates could fix these for all cases. This use of templates is likely
 381 // so far from the middle of the road that it is likely to be problematic in
 382 // many C++ compilers.
 383 //
 384 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value))
 385 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((address_word)(func_ptr)))
 386 
 387 // Unsigned byte types for os and stream.hpp
 388 
 389 // Unsigned one, two, four and eigth byte quantities used for describing
 390 // the .class file format. See JVM book chapter 4.
 391 
 392 typedef jubyte  u1;
 393 typedef jushort u2;
 394 typedef juint   u4;
 395 typedef julong  u8;
 396 
 397 const jubyte  max_jubyte  = (jubyte)-1;  // 0xFF       largest jubyte
 398 const jushort max_jushort = (jushort)-1; // 0xFFFF     largest jushort
 399 const juint   max_juint   = (juint)-1;   // 0xFFFFFFFF largest juint
 400 const julong  max_julong  = (julong)-1;  // 0xFF....FF largest julong
 401 
 402 typedef jbyte  s1;
 403 typedef jshort s2;
 404 typedef jint   s4;
 405 typedef jlong  s8;
 406 
 407 const jbyte min_jbyte = -(1 << 7);       // smallest jbyte
 408 const jbyte max_jbyte = (1 << 7) - 1;    // largest jbyte
 409 const jshort min_jshort = -(1 << 15);    // smallest jshort
 410 const jshort max_jshort = (1 << 15) - 1; // largest jshort
 411 
 412 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
 413 const jint max_jint = (juint)min_jint - 1;                     // 0x7FFFFFFF == largest jint
 414 
 415 //----------------------------------------------------------------------------------------------------
 416 // JVM spec restrictions
 417 
 418 const int max_method_code_size = 64*K - 1;  // JVM spec, 2nd ed. section 4.8.1 (p.134)
 419 
 420 //----------------------------------------------------------------------------------------------------
 421 // Default and minimum StringTableSize values
 422 
 423 const int defaultStringTableSize = NOT_LP64(1009) LP64_ONLY(60013);
 424 const int minimumStringTableSize = 1009;
 425 
 426 const int defaultSymbolTableSize = 20011;
 427 const int minimumSymbolTableSize = 1009;
 428 
 429 
 430 //----------------------------------------------------------------------------------------------------
 431 // HotSwap - for JVMTI   aka Class File Replacement and PopFrame
 432 //
 433 // Determines whether on-the-fly class replacement and frame popping are enabled.
 434 
 435 #define HOTSWAP
 436 
 437 //----------------------------------------------------------------------------------------------------
 438 // Object alignment, in units of HeapWords.
 439 //
 440 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and
 441 // reference fields can be naturally aligned.
 442 
 443 extern int MinObjAlignment;
 444 extern int MinObjAlignmentInBytes;
 445 extern int MinObjAlignmentInBytesMask;
 446 
 447 extern int LogMinObjAlignment;
 448 extern int LogMinObjAlignmentInBytes;
 449 
 450 const int LogKlassAlignmentInBytes = 3;
 451 const int LogKlassAlignment        = LogKlassAlignmentInBytes - LogHeapWordSize;
 452 const int KlassAlignmentInBytes    = 1 << LogKlassAlignmentInBytes;
 453 const int KlassAlignment           = KlassAlignmentInBytes / HeapWordSize;
 454 #if INCLUDE_VBC
 455 const int KlassPtrEvenOddMask      = (1 << (LogKlassAlignmentInBytes + 1)) - 1;
 456 #endif
 457 
 458 // Maximal size of heap where unscaled compression can be used. Also upper bound
 459 // for heap placement: 4GB.
 460 const  uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
 461 // Maximal size of heap where compressed oops can be used. Also upper bound for heap
 462 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes.
 463 extern uint64_t OopEncodingHeapMax;
 464 
 465 // Maximal size of compressed class space. Above this limit compression is not possible.
 466 // Also upper bound for placement of zero based class space. (Class space is further limited
 467 // to be < 3G, see arguments.cpp.)
 468 const  uint64_t KlassEncodingMetaspaceMax = (uint64_t(max_juint) + 1) << LogKlassAlignmentInBytes;
 469 
 470 // Machine dependent stuff
 471 
 472 // The maximum size of the code cache.  Can be overridden by targets.
 473 #define CODE_CACHE_SIZE_LIMIT (2*G)
 474 // Allow targets to reduce the default size of the code cache.
 475 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT
 476 
 477 #include CPU_HEADER(globalDefinitions)
 478 
 479 // To assure the IRIW property on processors that are not multiple copy
 480 // atomic, sync instructions must be issued between volatile reads to
 481 // assure their ordering, instead of after volatile stores.
 482 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models"
 483 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge)
 484 #ifdef CPU_NOT_MULTIPLE_COPY_ATOMIC
 485 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = true;
 486 #else
 487 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false;
 488 #endif
 489 
 490 // The expected size in bytes of a cache line, used to pad data structures.
 491 #ifndef DEFAULT_CACHE_LINE_SIZE
 492   #define DEFAULT_CACHE_LINE_SIZE 64
 493 #endif
 494 
 495 
 496 //----------------------------------------------------------------------------------------------------
 497 // Utility macros for compilers
 498 // used to silence compiler warnings
 499 
 500 #define Unused_Variable(var) var
 501 
 502 
 503 //----------------------------------------------------------------------------------------------------
 504 // Miscellaneous
 505 
 506 // 6302670 Eliminate Hotspot __fabsf dependency
 507 // All fabs() callers should call this function instead, which will implicitly
 508 // convert the operand to double, avoiding a dependency on __fabsf which
 509 // doesn't exist in early versions of Solaris 8.
 510 inline double fabsd(double value) {
 511   return fabs(value);
 512 }
 513 
 514 // Returns numerator/denominator as percentage value from 0 to 100. If denominator
 515 // is zero, return 0.0.
 516 template<typename T>
 517 inline double percent_of(T numerator, T denominator) {
 518   return denominator != 0 ? (double)numerator / denominator * 100.0 : 0.0;
 519 }
 520 
 521 //----------------------------------------------------------------------------------------------------
 522 // Special casts
 523 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern
 524 typedef union {
 525   jfloat f;
 526   jint i;
 527 } FloatIntConv;
 528 
 529 typedef union {
 530   jdouble d;
 531   jlong l;
 532   julong ul;
 533 } DoubleLongConv;
 534 
 535 inline jint    jint_cast    (jfloat  x)  { return ((FloatIntConv*)&x)->i; }
 536 inline jfloat  jfloat_cast  (jint    x)  { return ((FloatIntConv*)&x)->f; }
 537 
 538 inline jlong   jlong_cast   (jdouble x)  { return ((DoubleLongConv*)&x)->l;  }
 539 inline julong  julong_cast  (jdouble x)  { return ((DoubleLongConv*)&x)->ul; }
 540 inline jdouble jdouble_cast (jlong   x)  { return ((DoubleLongConv*)&x)->d;  }
 541 
 542 inline jint low (jlong value)                    { return jint(value); }
 543 inline jint high(jlong value)                    { return jint(value >> 32); }
 544 
 545 // the fancy casts are a hopefully portable way
 546 // to do unsigned 32 to 64 bit type conversion
 547 inline void set_low (jlong* value, jint low )    { *value &= (jlong)0xffffffff << 32;
 548                                                    *value |= (jlong)(julong)(juint)low; }
 549 
 550 inline void set_high(jlong* value, jint high)    { *value &= (jlong)(julong)(juint)0xffffffff;
 551                                                    *value |= (jlong)high       << 32; }
 552 
 553 inline jlong jlong_from(jint h, jint l) {
 554   jlong result = 0; // initialization to avoid warning
 555   set_high(&result, h);
 556   set_low(&result,  l);
 557   return result;
 558 }
 559 
 560 union jlong_accessor {
 561   jint  words[2];
 562   jlong long_value;
 563 };
 564 
 565 void basic_types_init(); // cannot define here; uses assert
 566 
 567 
 568 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 569 enum BasicType {
 570   T_BOOLEAN     =  4,
 571   T_CHAR        =  5,
 572   T_FLOAT       =  6,
 573   T_DOUBLE      =  7,
 574   T_BYTE        =  8,
 575   T_SHORT       =  9,
 576   T_INT         = 10,
 577   T_LONG        = 11,
 578   T_OBJECT      = 12,
 579   T_ARRAY       = 13,
 580   T_VOID        = 14,
 581   T_ADDRESS     = 15,
 582   T_NARROWOOP   = 16,
 583   T_METADATA    = 17,
 584   T_NARROWKLASS = 18,
 585   T_CONFLICT    = 19, // for stack value type with conflicting contents
 586   T_ILLEGAL     = 99
 587 };
 588 
 589 inline bool is_java_primitive(BasicType t) {
 590   return T_BOOLEAN <= t && t <= T_LONG;
 591 }
 592 
 593 inline bool is_subword_type(BasicType t) {
 594   // these guys are processed exactly like T_INT in calling sequences:
 595   return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);
 596 }
 597 
 598 inline bool is_signed_subword_type(BasicType t) {
 599   return (t == T_BYTE || t == T_SHORT);
 600 }
 601 
 602 // Convert a char from a classfile signature to a BasicType
 603 inline BasicType char2type(char c) {
 604   switch( c ) {
 605   case 'B': return T_BYTE;
 606   case 'C': return T_CHAR;
 607   case 'D': return T_DOUBLE;
 608   case 'F': return T_FLOAT;
 609   case 'I': return T_INT;
 610   case 'J': return T_LONG;
 611   case 'S': return T_SHORT;
 612   case 'Z': return T_BOOLEAN;
 613   case 'V': return T_VOID;
 614   case 'L': return T_OBJECT;
 615   case '[': return T_ARRAY;
 616   }
 617   return T_ILLEGAL;
 618 }
 619 
 620 extern char type2char_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 621 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }
 622 extern int type2size[T_CONFLICT+1];         // Map BasicType to result stack elements
 623 extern const char* type2name_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 624 inline const char* type2name(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2name_tab[t] : NULL; }
 625 extern BasicType name2type(const char* name);
 626 
 627 // Auxiliary math routines
 628 // least common multiple
 629 extern size_t lcm(size_t a, size_t b);
 630 
 631 
 632 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 633 enum BasicTypeSize {
 634   T_BOOLEAN_size     = 1,
 635   T_CHAR_size        = 1,
 636   T_FLOAT_size       = 1,
 637   T_DOUBLE_size      = 2,
 638   T_BYTE_size        = 1,
 639   T_SHORT_size       = 1,
 640   T_INT_size         = 1,
 641   T_LONG_size        = 2,
 642   T_OBJECT_size      = 1,
 643   T_ARRAY_size       = 1,
 644   T_NARROWOOP_size   = 1,
 645   T_NARROWKLASS_size = 1,
 646   T_VOID_size        = 0
 647 };
 648 
 649 
 650 // maps a BasicType to its instance field storage type:
 651 // all sub-word integral types are widened to T_INT
 652 extern BasicType type2field[T_CONFLICT+1];
 653 extern BasicType type2wfield[T_CONFLICT+1];
 654 
 655 
 656 // size in bytes
 657 enum ArrayElementSize {
 658   T_BOOLEAN_aelem_bytes     = 1,
 659   T_CHAR_aelem_bytes        = 2,
 660   T_FLOAT_aelem_bytes       = 4,
 661   T_DOUBLE_aelem_bytes      = 8,
 662   T_BYTE_aelem_bytes        = 1,
 663   T_SHORT_aelem_bytes       = 2,
 664   T_INT_aelem_bytes         = 4,
 665   T_LONG_aelem_bytes        = 8,
 666 #ifdef _LP64
 667   T_OBJECT_aelem_bytes      = 8,
 668   T_ARRAY_aelem_bytes       = 8,
 669 #else
 670   T_OBJECT_aelem_bytes      = 4,
 671   T_ARRAY_aelem_bytes       = 4,
 672 #endif
 673   T_NARROWOOP_aelem_bytes   = 4,
 674   T_NARROWKLASS_aelem_bytes = 4,
 675   T_VOID_aelem_bytes        = 0
 676 };
 677 
 678 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element
 679 #ifdef ASSERT
 680 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts
 681 #else
 682 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; }
 683 #endif
 684 
 685 
 686 // JavaValue serves as a container for arbitrary Java values.
 687 
 688 class JavaValue {
 689 
 690  public:
 691   typedef union JavaCallValue {
 692     jfloat   f;
 693     jdouble  d;
 694     jint     i;
 695     jlong    l;
 696     jobject  h;
 697   } JavaCallValue;
 698 
 699  private:
 700   BasicType _type;
 701   JavaCallValue _value;
 702 
 703  public:
 704   JavaValue(BasicType t = T_ILLEGAL) { _type = t; }
 705 
 706   JavaValue(jfloat value) {
 707     _type    = T_FLOAT;
 708     _value.f = value;
 709   }
 710 
 711   JavaValue(jdouble value) {
 712     _type    = T_DOUBLE;
 713     _value.d = value;
 714   }
 715 
 716  jfloat get_jfloat() const { return _value.f; }
 717  jdouble get_jdouble() const { return _value.d; }
 718  jint get_jint() const { return _value.i; }
 719  jlong get_jlong() const { return _value.l; }
 720  jobject get_jobject() const { return _value.h; }
 721  JavaCallValue* get_value_addr() { return &_value; }
 722  BasicType get_type() const { return _type; }
 723 
 724  void set_jfloat(jfloat f) { _value.f = f;}
 725  void set_jdouble(jdouble d) { _value.d = d;}
 726  void set_jint(jint i) { _value.i = i;}
 727  void set_jlong(jlong l) { _value.l = l;}
 728  void set_jobject(jobject h) { _value.h = h;}
 729  void set_type(BasicType t) { _type = t; }
 730 
 731  jboolean get_jboolean() const { return (jboolean) (_value.i);}
 732  jbyte get_jbyte() const { return (jbyte) (_value.i);}
 733  jchar get_jchar() const { return (jchar) (_value.i);}
 734  jshort get_jshort() const { return (jshort) (_value.i);}
 735 
 736 };
 737 
 738 
 739 #define STACK_BIAS      0
 740 // V9 Sparc CPU's running in 64 Bit mode use a stack bias of 7ff
 741 // in order to extend the reach of the stack pointer.
 742 #if defined(SPARC) && defined(_LP64)
 743 #undef STACK_BIAS
 744 #define STACK_BIAS      0x7ff
 745 #endif
 746 
 747 
 748 // TosState describes the top-of-stack state before and after the execution of
 749 // a bytecode or method. The top-of-stack value may be cached in one or more CPU
 750 // registers. The TosState corresponds to the 'machine representation' of this cached
 751 // value. There's 4 states corresponding to the JAVA types int, long, float & double
 752 // as well as a 5th state in case the top-of-stack value is actually on the top
 753 // of stack (in memory) and thus not cached. The atos state corresponds to the itos
 754 // state when it comes to machine representation but is used separately for (oop)
 755 // type specific operations (e.g. verification code).
 756 
 757 enum TosState {         // describes the tos cache contents
 758   btos = 0,             // byte, bool tos cached
 759   ztos = 1,             // byte, bool tos cached
 760   ctos = 2,             // char tos cached
 761   stos = 3,             // short tos cached
 762   itos = 4,             // int tos cached
 763   ltos = 5,             // long tos cached
 764   ftos = 6,             // float tos cached
 765   dtos = 7,             // double tos cached
 766   atos = 8,             // object cached
 767   vtos = 9,             // tos not cached
 768   number_of_states,
 769   ilgl                  // illegal state: should not occur
 770 };
 771 
 772 
 773 inline TosState as_TosState(BasicType type) {
 774   switch (type) {
 775     case T_BYTE   : return btos;
 776     case T_BOOLEAN: return ztos;
 777     case T_CHAR   : return ctos;
 778     case T_SHORT  : return stos;
 779     case T_INT    : return itos;
 780     case T_LONG   : return ltos;
 781     case T_FLOAT  : return ftos;
 782     case T_DOUBLE : return dtos;
 783     case T_VOID   : return vtos;
 784     case T_ARRAY  : // fall through
 785     case T_OBJECT : return atos;
 786     default       : return ilgl;
 787   }
 788 }
 789 
 790 inline BasicType as_BasicType(TosState state) {
 791   switch (state) {
 792     case btos : return T_BYTE;
 793     case ztos : return T_BOOLEAN;
 794     case ctos : return T_CHAR;
 795     case stos : return T_SHORT;
 796     case itos : return T_INT;
 797     case ltos : return T_LONG;
 798     case ftos : return T_FLOAT;
 799     case dtos : return T_DOUBLE;
 800     case atos : return T_OBJECT;
 801     case vtos : return T_VOID;
 802     default   : return T_ILLEGAL;
 803   }
 804 }
 805 
 806 
 807 // Helper function to convert BasicType info into TosState
 808 // Note: Cannot define here as it uses global constant at the time being.
 809 TosState as_TosState(BasicType type);
 810 
 811 
 812 // JavaThreadState keeps track of which part of the code a thread is executing in. This
 813 // information is needed by the safepoint code.
 814 //
 815 // There are 4 essential states:
 816 //
 817 //  _thread_new         : Just started, but not executed init. code yet (most likely still in OS init code)
 818 //  _thread_in_native   : In native code. This is a safepoint region, since all oops will be in jobject handles
 819 //  _thread_in_vm       : Executing in the vm
 820 //  _thread_in_Java     : Executing either interpreted or compiled Java code (or could be in a stub)
 821 //
 822 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in
 823 // a transition from one state to another. These extra states makes it possible for the safepoint code to
 824 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.
 825 //
 826 // Given a state, the xxxx_trans state can always be found by adding 1.
 827 //
 828 enum JavaThreadState {
 829   _thread_uninitialized     =  0, // should never happen (missing initialization)
 830   _thread_new               =  2, // just starting up, i.e., in process of being initialized
 831   _thread_new_trans         =  3, // corresponding transition state (not used, included for completness)
 832   _thread_in_native         =  4, // running in native code
 833   _thread_in_native_trans   =  5, // corresponding transition state
 834   _thread_in_vm             =  6, // running in VM
 835   _thread_in_vm_trans       =  7, // corresponding transition state
 836   _thread_in_Java           =  8, // running in Java or in stub code
 837   _thread_in_Java_trans     =  9, // corresponding transition state (not used, included for completness)
 838   _thread_blocked           = 10, // blocked in vm
 839   _thread_blocked_trans     = 11, // corresponding transition state
 840   _thread_max_state         = 12  // maximum thread state+1 - used for statistics allocation
 841 };
 842 
 843 
 844 
 845 //----------------------------------------------------------------------------------------------------
 846 // 'Forward' declarations of frequently used classes
 847 // (in order to reduce interface dependencies & reduce
 848 // number of unnecessary compilations after changes)
 849 
 850 class ClassFileStream;
 851 
 852 class Event;
 853 
 854 class Thread;
 855 class  VMThread;
 856 class  JavaThread;
 857 class Threads;
 858 
 859 class VM_Operation;
 860 class VMOperationQueue;
 861 
 862 class CodeBlob;
 863 class  CompiledMethod;
 864 class   nmethod;
 865 class RuntimeBlob;
 866 class  OSRAdapter;
 867 class  I2CAdapter;
 868 class  C2IAdapter;
 869 class CompiledIC;
 870 class relocInfo;
 871 class ScopeDesc;
 872 class PcDesc;
 873 
 874 class Recompiler;
 875 class Recompilee;
 876 class RecompilationPolicy;
 877 class RFrame;
 878 class  CompiledRFrame;
 879 class  InterpretedRFrame;
 880 
 881 class vframe;
 882 class   javaVFrame;
 883 class     interpretedVFrame;
 884 class     compiledVFrame;
 885 class     deoptimizedVFrame;
 886 class   externalVFrame;
 887 class     entryVFrame;
 888 
 889 class RegisterMap;
 890 
 891 class Mutex;
 892 class Monitor;
 893 class BasicLock;
 894 class BasicObjectLock;
 895 
 896 class PeriodicTask;
 897 
 898 class JavaCallWrapper;
 899 
 900 class   oopDesc;
 901 class   metaDataOopDesc;
 902 
 903 class NativeCall;
 904 
 905 class zone;
 906 
 907 class StubQueue;
 908 
 909 class outputStream;
 910 
 911 class ResourceArea;
 912 
 913 class DebugInformationRecorder;
 914 class ScopeValue;
 915 class CompressedStream;
 916 class   DebugInfoReadStream;
 917 class   DebugInfoWriteStream;
 918 class LocationValue;
 919 class ConstantValue;
 920 class IllegalValue;
 921 
 922 class PrivilegedElement;
 923 class MonitorArray;
 924 
 925 class MonitorInfo;
 926 
 927 class OffsetClosure;
 928 class OopMapCache;
 929 class InterpreterOopMap;
 930 class OopMapCacheEntry;
 931 class OSThread;
 932 
 933 typedef int (*OSThreadStartFunc)(void*);
 934 
 935 class Space;
 936 
 937 class JavaValue;
 938 class methodHandle;
 939 class JavaCallArguments;
 940 
 941 // Basic support for errors.
 942 extern void basic_fatal(const char* msg);
 943 
 944 //----------------------------------------------------------------------------------------------------
 945 // Special constants for debugging
 946 
 947 const jint     badInt           = -3;                       // generic "bad int" value
 948 const long     badAddressVal    = -2;                       // generic "bad address" value
 949 const long     badOopVal        = -1;                       // generic "bad oop" value
 950 const intptr_t badHeapOopVal    = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC
 951 const int      badStackSegVal   = 0xCA;                     // value used to zap stack segments
 952 const int      badHandleValue   = 0xBC;                     // value used to zap vm handle area
 953 const int      badResourceValue = 0xAB;                     // value used to zap resource area
 954 const int      freeBlockPad     = 0xBA;                     // value used to pad freed blocks.
 955 const int      uninitBlockPad   = 0xF1;                     // value used to zap newly malloc'd blocks.
 956 const juint    uninitMetaWordVal= 0xf7f7f7f7;               // value used to zap newly allocated metachunk
 957 const juint    badHeapWordVal   = 0xBAADBABE;               // value used to zap heap after GC
 958 const juint    badMetaWordVal   = 0xBAADFADE;               // value used to zap metadata heap after GC
 959 const int      badCodeHeapNewVal= 0xCC;                     // value used to zap Code heap at allocation
 960 const int      badCodeHeapFreeVal = 0xDD;                   // value used to zap Code heap at deallocation
 961 
 962 
 963 // (These must be implemented as #defines because C++ compilers are
 964 // not obligated to inline non-integral constants!)
 965 #define       badAddress        ((address)::badAddressVal)
 966 #define       badOop            (cast_to_oop(::badOopVal))
 967 #define       badHeapWord       (::badHeapWordVal)
 968 
 969 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)
 970 #define TASKQUEUE_SIZE (NOT_LP64(1<<14) LP64_ONLY(1<<17))
 971 
 972 //----------------------------------------------------------------------------------------------------
 973 // Utility functions for bitfield manipulations
 974 
 975 const intptr_t AllBits    = ~0; // all bits set in a word
 976 const intptr_t NoBits     =  0; // no bits set in a word
 977 const jlong    NoLongBits =  0; // no bits set in a long
 978 const intptr_t OneBit     =  1; // only right_most bit set in a word
 979 
 980 // get a word with the n.th or the right-most or left-most n bits set
 981 // (note: #define used only so that they can be used in enum constant definitions)
 982 #define nth_bit(n)        (((n) >= BitsPerWord) ? 0 : (OneBit << (n)))
 983 #define right_n_bits(n)   (nth_bit(n) - 1)
 984 #define left_n_bits(n)    (right_n_bits(n) << (((n) >= BitsPerWord) ? 0 : (BitsPerWord - (n))))
 985 
 986 // bit-operations using a mask m
 987 inline void   set_bits    (intptr_t& x, intptr_t m) { x |= m; }
 988 inline void clear_bits    (intptr_t& x, intptr_t m) { x &= ~m; }
 989 inline intptr_t mask_bits      (intptr_t  x, intptr_t m) { return x & m; }
 990 inline jlong    mask_long_bits (jlong     x, jlong    m) { return x & m; }
 991 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }
 992 
 993 // bit-operations using the n.th bit
 994 inline void    set_nth_bit(intptr_t& x, int n) { set_bits  (x, nth_bit(n)); }
 995 inline void  clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }
 996 inline bool is_set_nth_bit(intptr_t  x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }
 997 
 998 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)
 999 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {
1000   return mask_bits(x >> start_bit_no, right_n_bits(field_length));
1001 }
1002 
1003 
1004 //----------------------------------------------------------------------------------------------------
1005 // Utility functions for integers
1006 
1007 // Avoid use of global min/max macros which may cause unwanted double
1008 // evaluation of arguments.
1009 #ifdef max
1010 #undef max
1011 #endif
1012 
1013 #ifdef min
1014 #undef min
1015 #endif
1016 
1017 // The following defines serve the purpose of preventing use of accidentally
1018 // included min max macros from compiling, while continuing to allow innocent
1019 // min and max identifiers in the code to compile as intended.
1020 #define max max
1021 #define min min
1022 
1023 // It is necessary to use templates here. Having normal overloaded
1024 // functions does not work because it is necessary to provide both 32-
1025 // and 64-bit overloaded functions, which does not work, and having
1026 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)
1027 // will be even more error-prone than macros.
1028 template<class T> inline T MAX2(T a, T b)           { return (a > b) ? a : b; }
1029 template<class T> inline T MIN2(T a, T b)           { return (a < b) ? a : b; }
1030 template<class T> inline T MAX3(T a, T b, T c)      { return MAX2(MAX2(a, b), c); }
1031 template<class T> inline T MIN3(T a, T b, T c)      { return MIN2(MIN2(a, b), c); }
1032 template<class T> inline T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }
1033 template<class T> inline T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }
1034 
1035 template<class T> inline T ABS(T x)                 { return (x > 0) ? x : -x; }
1036 
1037 // true if x is a power of 2, false otherwise
1038 inline bool is_power_of_2(intptr_t x) {
1039   return ((x != NoBits) && (mask_bits(x, x - 1) == NoBits));
1040 }
1041 
1042 // long version of is_power_of_2
1043 inline bool is_power_of_2_long(jlong x) {
1044   return ((x != NoLongBits) && (mask_long_bits(x, x - 1) == NoLongBits));
1045 }
1046 
1047 // Returns largest i such that 2^i <= x.
1048 // If x < 0, the function returns 31 on a 32-bit machine and 63 on a 64-bit machine.
1049 // If x == 0, the function returns -1.
1050 inline int log2_intptr(intptr_t x) {
1051   int i = -1;
1052   uintptr_t p = 1;
1053   while (p != 0 && p <= (uintptr_t)x) {
1054     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
1055     i++; p *= 2;
1056   }
1057   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))
1058   // If p = 0, overflow has occurred and i = 31 or i = 63 (depending on the machine word size).
1059   return i;
1060 }
1061 
1062 //* largest i such that 2^i <= x
1063 //  A negative value of 'x' will return '63'
1064 inline int log2_long(jlong x) {
1065   int i = -1;
1066   julong p =  1;
1067   while (p != 0 && p <= (julong)x) {
1068     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
1069     i++; p *= 2;
1070   }
1071   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))
1072   // (if p = 0 then overflow occurred and i = 63)
1073   return i;
1074 }
1075 
1076 //* the argument must be exactly a power of 2
1077 inline int exact_log2(intptr_t x) {
1078   assert(is_power_of_2(x), "x must be a power of 2: " INTPTR_FORMAT, x);
1079   return log2_intptr(x);
1080 }
1081 
1082 //* the argument must be exactly a power of 2
1083 inline int exact_log2_long(jlong x) {
1084   assert(is_power_of_2_long(x), "x must be a power of 2: " JLONG_FORMAT, x);
1085   return log2_long(x);
1086 }
1087 
1088 inline bool is_odd (intx x) { return x & 1;      }
1089 inline bool is_even(intx x) { return !is_odd(x); }
1090 
1091 // "to" should be greater than "from."
1092 inline intx byte_size(void* from, void* to) {
1093   return (address)to - (address)from;
1094 }
1095 
1096 //----------------------------------------------------------------------------------------------------
1097 // Avoid non-portable casts with these routines (DEPRECATED)
1098 
1099 // NOTE: USE Bytes class INSTEAD WHERE POSSIBLE
1100 //       Bytes is optimized machine-specifically and may be much faster then the portable routines below.
1101 
1102 // Given sequence of four bytes, build into a 32-bit word
1103 // following the conventions used in class files.
1104 // On the 386, this could be realized with a simple address cast.
1105 //
1106 
1107 // This routine takes eight bytes:
1108 inline u8 build_u8_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {
1109   return  (( u8(c1) << 56 )  &  ( u8(0xff) << 56 ))
1110        |  (( u8(c2) << 48 )  &  ( u8(0xff) << 48 ))
1111        |  (( u8(c3) << 40 )  &  ( u8(0xff) << 40 ))
1112        |  (( u8(c4) << 32 )  &  ( u8(0xff) << 32 ))
1113        |  (( u8(c5) << 24 )  &  ( u8(0xff) << 24 ))
1114        |  (( u8(c6) << 16 )  &  ( u8(0xff) << 16 ))
1115        |  (( u8(c7) <<  8 )  &  ( u8(0xff) <<  8 ))
1116        |  (( u8(c8) <<  0 )  &  ( u8(0xff) <<  0 ));
1117 }
1118 
1119 // This routine takes four bytes:
1120 inline u4 build_u4_from( u1 c1, u1 c2, u1 c3, u1 c4 ) {
1121   return  (( u4(c1) << 24 )  &  0xff000000)
1122        |  (( u4(c2) << 16 )  &  0x00ff0000)
1123        |  (( u4(c3) <<  8 )  &  0x0000ff00)
1124        |  (( u4(c4) <<  0 )  &  0x000000ff);
1125 }
1126 
1127 // And this one works if the four bytes are contiguous in memory:
1128 inline u4 build_u4_from( u1* p ) {
1129   return  build_u4_from( p[0], p[1], p[2], p[3] );
1130 }
1131 
1132 // Ditto for two-byte ints:
1133 inline u2 build_u2_from( u1 c1, u1 c2 ) {
1134   return  u2((( u2(c1) <<  8 )  &  0xff00)
1135           |  (( u2(c2) <<  0 )  &  0x00ff));
1136 }
1137 
1138 // And this one works if the two bytes are contiguous in memory:
1139 inline u2 build_u2_from( u1* p ) {
1140   return  build_u2_from( p[0], p[1] );
1141 }
1142 
1143 // Ditto for floats:
1144 inline jfloat build_float_from( u1 c1, u1 c2, u1 c3, u1 c4 ) {
1145   u4 u = build_u4_from( c1, c2, c3, c4 );
1146   return  *(jfloat*)&u;
1147 }
1148 
1149 inline jfloat build_float_from( u1* p ) {
1150   u4 u = build_u4_from( p );
1151   return  *(jfloat*)&u;
1152 }
1153 
1154 
1155 // now (64-bit) longs
1156 
1157 inline jlong build_long_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {
1158   return  (( jlong(c1) << 56 )  &  ( jlong(0xff) << 56 ))
1159        |  (( jlong(c2) << 48 )  &  ( jlong(0xff) << 48 ))
1160        |  (( jlong(c3) << 40 )  &  ( jlong(0xff) << 40 ))
1161        |  (( jlong(c4) << 32 )  &  ( jlong(0xff) << 32 ))
1162        |  (( jlong(c5) << 24 )  &  ( jlong(0xff) << 24 ))
1163        |  (( jlong(c6) << 16 )  &  ( jlong(0xff) << 16 ))
1164        |  (( jlong(c7) <<  8 )  &  ( jlong(0xff) <<  8 ))
1165        |  (( jlong(c8) <<  0 )  &  ( jlong(0xff) <<  0 ));
1166 }
1167 
1168 inline jlong build_long_from( u1* p ) {
1169   return  build_long_from( p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7] );
1170 }
1171 
1172 
1173 // Doubles, too!
1174 inline jdouble build_double_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {
1175   jlong u = build_long_from( c1, c2, c3, c4, c5, c6, c7, c8 );
1176   return  *(jdouble*)&u;
1177 }
1178 
1179 inline jdouble build_double_from( u1* p ) {
1180   jlong u = build_long_from( p );
1181   return  *(jdouble*)&u;
1182 }
1183 
1184 
1185 // Portable routines to go the other way:
1186 
1187 inline void explode_short_to( u2 x, u1& c1, u1& c2 ) {
1188   c1 = u1(x >> 8);
1189   c2 = u1(x);
1190 }
1191 
1192 inline void explode_short_to( u2 x, u1* p ) {
1193   explode_short_to( x, p[0], p[1]);
1194 }
1195 
1196 inline void explode_int_to( u4 x, u1& c1, u1& c2, u1& c3, u1& c4 ) {
1197   c1 = u1(x >> 24);
1198   c2 = u1(x >> 16);
1199   c3 = u1(x >>  8);
1200   c4 = u1(x);
1201 }
1202 
1203 inline void explode_int_to( u4 x, u1* p ) {
1204   explode_int_to( x, p[0], p[1], p[2], p[3]);
1205 }
1206 
1207 
1208 // Pack and extract shorts to/from ints:
1209 
1210 inline int extract_low_short_from_int(jint x) {
1211   return x & 0xffff;
1212 }
1213 
1214 inline int extract_high_short_from_int(jint x) {
1215   return (x >> 16) & 0xffff;
1216 }
1217 
1218 inline int build_int_from_shorts( jushort low, jushort high ) {
1219   return ((int)((unsigned int)high << 16) | (unsigned int)low);
1220 }
1221 
1222 // Convert pointer to intptr_t, for use in printing pointers.
1223 inline intptr_t p2i(const void * p) {
1224   return (intptr_t) p;
1225 }
1226 
1227 // swap a & b
1228 template<class T> static void swap(T& a, T& b) {
1229   T tmp = a;
1230   a = b;
1231   b = tmp;
1232 }
1233 
1234 #define ARRAY_SIZE(array) (sizeof(array)/sizeof((array)[0]))
1235 
1236 //----------------------------------------------------------------------------------------------------
1237 // Sum and product which can never overflow: they wrap, just like the
1238 // Java operations.  Note that we don't intend these to be used for
1239 // general-purpose arithmetic: their purpose is to emulate Java
1240 // operations.
1241 
1242 // The goal of this code to avoid undefined or implementation-defined
1243 // behavior.  The use of an lvalue to reference cast is explicitly
1244 // permitted by Lvalues and rvalues [basic.lval].  [Section 3.10 Para
1245 // 15 in C++03]
1246 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE)  \
1247 inline TYPE NAME (TYPE in1, TYPE in2) {                 \
1248   UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \
1249   ures OP ## = static_cast<UNSIGNED_TYPE>(in2);         \
1250   return reinterpret_cast<TYPE&>(ures);                 \
1251 }
1252 
1253 JAVA_INTEGER_OP(+, java_add, jint, juint)
1254 JAVA_INTEGER_OP(-, java_subtract, jint, juint)
1255 JAVA_INTEGER_OP(*, java_multiply, jint, juint)
1256 JAVA_INTEGER_OP(+, java_add, jlong, julong)
1257 JAVA_INTEGER_OP(-, java_subtract, jlong, julong)
1258 JAVA_INTEGER_OP(*, java_multiply, jlong, julong)
1259 
1260 #undef JAVA_INTEGER_OP
1261 
1262 // Dereference vptr
1263 // All C++ compilers that we know of have the vtbl pointer in the first
1264 // word.  If there are exceptions, this function needs to be made compiler
1265 // specific.
1266 static inline void* dereference_vptr(const void* addr) {
1267   return *(void**)addr;
1268 }
1269 
1270 #endif // SHARE_VM_UTILITIES_GLOBALDEFINITIONS_HPP