1 /*
   2  * Copyright (c) 1997, 2018, 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 #ifndef ATTRIBUTE_ALIGNED
  43 #define ATTRIBUTE_ALIGNED(x)
  44 #endif
  45 
  46 // This file holds all globally used constants & types, class (forward)
  47 // declarations and a few frequently used utility functions.
  48 
  49 //----------------------------------------------------------------------------------------------------
  50 // Printf-style formatters for fixed- and variable-width types as pointers and
  51 // integers.  These are derived from the definitions in inttypes.h.  If the platform
  52 // doesn't provide appropriate definitions, they should be provided in
  53 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp)
  54 
  55 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false")
  56 
  57 // Format 32-bit quantities.
  58 #define INT32_FORMAT           "%" PRId32
  59 #define UINT32_FORMAT          "%" PRIu32
  60 #define INT32_FORMAT_W(width)  "%" #width PRId32
  61 #define UINT32_FORMAT_W(width) "%" #width PRIu32
  62 
  63 #define PTR32_FORMAT           "0x%08" PRIx32
  64 #define PTR32_FORMAT_W(width)  "0x%" #width PRIx32
  65 
  66 // Format 64-bit quantities.
  67 #define INT64_FORMAT           "%" PRId64
  68 #define UINT64_FORMAT          "%" PRIu64
  69 #define UINT64_FORMAT_X        "%" PRIx64
  70 #define INT64_FORMAT_W(width)  "%" #width PRId64
  71 #define UINT64_FORMAT_W(width) "%" #width PRIu64
  72 
  73 #define PTR64_FORMAT           "0x%016" PRIx64
  74 
  75 // Format jlong, if necessary
  76 #ifndef JLONG_FORMAT
  77 #define JLONG_FORMAT           INT64_FORMAT
  78 #endif
  79 #ifndef JULONG_FORMAT
  80 #define JULONG_FORMAT          UINT64_FORMAT
  81 #endif
  82 #ifndef JULONG_FORMAT_X
  83 #define JULONG_FORMAT_X        UINT64_FORMAT_X
  84 #endif
  85 
  86 // Format pointers which change size between 32- and 64-bit.
  87 #ifdef  _LP64
  88 #define INTPTR_FORMAT "0x%016" PRIxPTR
  89 #define PTR_FORMAT    "0x%016" PRIxPTR
  90 #else   // !_LP64
  91 #define INTPTR_FORMAT "0x%08"  PRIxPTR
  92 #define PTR_FORMAT    "0x%08"  PRIxPTR
  93 #endif  // _LP64
  94 
  95 // Format pointers without leading zeros
  96 #define INTPTRNZ_FORMAT "0x%"  PRIxPTR
  97 
  98 #define INTPTR_FORMAT_W(width)   "%" #width PRIxPTR
  99 
 100 #define SSIZE_FORMAT             "%"   PRIdPTR
 101 #define SIZE_FORMAT              "%"   PRIuPTR
 102 #define SIZE_FORMAT_HEX          "0x%" PRIxPTR
 103 #define SSIZE_FORMAT_W(width)    "%"   #width PRIdPTR
 104 #define SIZE_FORMAT_W(width)     "%"   #width PRIuPTR
 105 #define SIZE_FORMAT_HEX_W(width) "0x%" #width PRIxPTR
 106 
 107 #define INTX_FORMAT           "%" PRIdPTR
 108 #define UINTX_FORMAT          "%" PRIuPTR
 109 #define INTX_FORMAT_W(width)  "%" #width PRIdPTR
 110 #define UINTX_FORMAT_W(width) "%" #width PRIuPTR
 111 
 112 //----------------------------------------------------------------------------------------------------
 113 // Constants
 114 
 115 const int LogBytesPerShort   = 1;
 116 const int LogBytesPerInt     = 2;
 117 #ifdef _LP64
 118 const int LogBytesPerWord    = 3;
 119 #else
 120 const int LogBytesPerWord    = 2;
 121 #endif
 122 const int LogBytesPerLong    = 3;
 123 
 124 const int BytesPerShort      = 1 << LogBytesPerShort;
 125 const int BytesPerInt        = 1 << LogBytesPerInt;
 126 const int BytesPerWord       = 1 << LogBytesPerWord;
 127 const int BytesPerLong       = 1 << LogBytesPerLong;
 128 
 129 const int LogBitsPerByte     = 3;
 130 const int LogBitsPerShort    = LogBitsPerByte + LogBytesPerShort;
 131 const int LogBitsPerInt      = LogBitsPerByte + LogBytesPerInt;
 132 const int LogBitsPerWord     = LogBitsPerByte + LogBytesPerWord;
 133 const int LogBitsPerLong     = LogBitsPerByte + LogBytesPerLong;
 134 
 135 const int BitsPerByte        = 1 << LogBitsPerByte;
 136 const int BitsPerShort       = 1 << LogBitsPerShort;
 137 const int BitsPerInt         = 1 << LogBitsPerInt;
 138 const int BitsPerWord        = 1 << LogBitsPerWord;
 139 const int BitsPerLong        = 1 << LogBitsPerLong;
 140 
 141 const int WordAlignmentMask  = (1 << LogBytesPerWord) - 1;
 142 const int LongAlignmentMask  = (1 << LogBytesPerLong) - 1;
 143 
 144 const int WordsPerLong       = 2;       // Number of stack entries for longs
 145 
 146 const int oopSize            = sizeof(char*); // Full-width oop
 147 extern int heapOopSize;                       // Oop within a java object
 148 const int wordSize           = sizeof(char*);
 149 const int longSize           = sizeof(jlong);
 150 const int jintSize           = sizeof(jint);
 151 const int size_tSize         = sizeof(size_t);
 152 
 153 const int BytesPerOop        = BytesPerWord;  // Full-width oop
 154 
 155 extern int LogBytesPerHeapOop;                // Oop within a java object
 156 extern int LogBitsPerHeapOop;
 157 extern int BytesPerHeapOop;
 158 extern int BitsPerHeapOop;
 159 
 160 const int BitsPerJavaInteger = 32;
 161 const int BitsPerJavaLong    = 64;
 162 const int BitsPerSize_t      = size_tSize * BitsPerByte;
 163 
 164 // Size of a char[] needed to represent a jint as a string in decimal.
 165 const int jintAsStringSize = 12;
 166 
 167 // An opaque struct of heap-word width, so that HeapWord* can be a generic
 168 // pointer into the heap.  We require that object sizes be measured in
 169 // units of heap words, so that that
 170 //   HeapWord* hw;
 171 //   hw += oop(hw)->foo();
 172 // works, where foo is a method (like size or scavenge) that returns the
 173 // object size.
 174 class HeapWord {
 175   friend class VMStructs;
 176  private:
 177   char* i;
 178 #ifndef PRODUCT
 179  public:
 180   char* value() { return i; }
 181 #endif
 182 };
 183 
 184 // Analogous opaque struct for metadata allocated from
 185 // metaspaces.
 186 class MetaWord {
 187  private:
 188   char* i;
 189 };
 190 
 191 // HeapWordSize must be 2^LogHeapWordSize.
 192 const int HeapWordSize        = sizeof(HeapWord);
 193 #ifdef _LP64
 194 const int LogHeapWordSize     = 3;
 195 #else
 196 const int LogHeapWordSize     = 2;
 197 #endif
 198 const int HeapWordsPerLong    = BytesPerLong / HeapWordSize;
 199 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize;
 200 
 201 // The minimum number of native machine words necessary to contain "byte_size"
 202 // bytes.
 203 inline size_t heap_word_size(size_t byte_size) {
 204   return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize;
 205 }
 206 
 207 //-------------------------------------------
 208 // Constant for jlong (standardized by C++11)
 209 
 210 // Build a 64bit integer constant
 211 #define CONST64(x)  (x ## LL)
 212 #define UCONST64(x) (x ## ULL)
 213 
 214 const jlong min_jlong = CONST64(0x8000000000000000);
 215 const jlong max_jlong = CONST64(0x7fffffffffffffff);
 216 
 217 const size_t K                  = 1024;
 218 const size_t M                  = K*K;
 219 const size_t G                  = M*K;
 220 const size_t HWperKB            = K / sizeof(HeapWord);
 221 
 222 // Constants for converting from a base unit to milli-base units.  For
 223 // example from seconds to milliseconds and microseconds
 224 
 225 const int MILLIUNITS    = 1000;         // milli units per base unit
 226 const int MICROUNITS    = 1000000;      // micro units per base unit
 227 const int NANOUNITS     = 1000000000;   // nano units per base unit
 228 
 229 const jlong NANOSECS_PER_SEC      = CONST64(1000000000);
 230 const jint  NANOSECS_PER_MILLISEC = 1000000;
 231 
 232 inline const char* proper_unit_for_byte_size(size_t s) {
 233 #ifdef _LP64
 234   if (s >= 10*G) {
 235     return "G";
 236   }
 237 #endif
 238   if (s >= 10*M) {
 239     return "M";
 240   } else if (s >= 10*K) {
 241     return "K";
 242   } else {
 243     return "B";
 244   }
 245 }
 246 
 247 template <class T>
 248 inline T byte_size_in_proper_unit(T s) {
 249 #ifdef _LP64
 250   if (s >= 10*G) {
 251     return (T)(s/G);
 252   }
 253 #endif
 254   if (s >= 10*M) {
 255     return (T)(s/M);
 256   } else if (s >= 10*K) {
 257     return (T)(s/K);
 258   } else {
 259     return s;
 260   }
 261 }
 262 
 263 inline const char* exact_unit_for_byte_size(size_t s) {
 264 #ifdef _LP64
 265   if (s >= G && (s % G) == 0) {
 266     return "G";
 267   }
 268 #endif
 269   if (s >= M && (s % M) == 0) {
 270     return "M";
 271   }
 272   if (s >= K && (s % K) == 0) {
 273     return "K";
 274   }
 275   return "B";
 276 }
 277 
 278 inline size_t byte_size_in_exact_unit(size_t s) {
 279 #ifdef _LP64
 280   if (s >= G && (s % G) == 0) {
 281     return s / G;
 282   }
 283 #endif
 284   if (s >= M && (s % M) == 0) {
 285     return s / M;
 286   }
 287   if (s >= K && (s % K) == 0) {
 288     return s / K;
 289   }
 290   return s;
 291 }
 292 
 293 //----------------------------------------------------------------------------------------------------
 294 // VM type definitions
 295 
 296 // intx and uintx are the 'extended' int and 'extended' unsigned int types;
 297 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.
 298 
 299 typedef intptr_t  intx;
 300 typedef uintptr_t uintx;
 301 
 302 const intx  min_intx  = (intx)1 << (sizeof(intx)*BitsPerByte-1);
 303 const intx  max_intx  = (uintx)min_intx - 1;
 304 const uintx max_uintx = (uintx)-1;
 305 
 306 // Table of values:
 307 //      sizeof intx         4               8
 308 // min_intx             0x80000000      0x8000000000000000
 309 // max_intx             0x7FFFFFFF      0x7FFFFFFFFFFFFFFF
 310 // max_uintx            0xFFFFFFFF      0xFFFFFFFFFFFFFFFF
 311 
 312 typedef unsigned int uint;   NEEDS_CLEANUP
 313 
 314 
 315 //----------------------------------------------------------------------------------------------------
 316 // Java type definitions
 317 
 318 // All kinds of 'plain' byte addresses
 319 typedef   signed char s_char;
 320 typedef unsigned char u_char;
 321 typedef u_char*       address;
 322 typedef uintptr_t     address_word; // unsigned integer which will hold a pointer
 323                                     // except for some implementations of a C++
 324                                     // linkage pointer to function. Should never
 325                                     // need one of those to be placed in this
 326                                     // type anyway.
 327 
 328 //  Utility functions to "portably" (?) bit twiddle pointers
 329 //  Where portable means keep ANSI C++ compilers quiet
 330 
 331 inline address       set_address_bits(address x, int m)       { return address(intptr_t(x) | m); }
 332 inline address       clear_address_bits(address x, int m)     { return address(intptr_t(x) & ~m); }
 333 
 334 //  Utility functions to "portably" make cast to/from function pointers.
 335 
 336 inline address_word  mask_address_bits(address x, int m)      { return address_word(x) & m; }
 337 inline address_word  castable_address(address x)              { return address_word(x) ; }
 338 inline address_word  castable_address(void* x)                { return address_word(x) ; }
 339 
 340 // Pointer subtraction.
 341 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have
 342 // the range we might need to find differences from one end of the heap
 343 // to the other.
 344 // A typical use might be:
 345 //     if (pointer_delta(end(), top()) >= size) {
 346 //       // enough room for an object of size
 347 //       ...
 348 // and then additions like
 349 //       ... top() + size ...
 350 // are safe because we know that top() is at least size below end().
 351 inline size_t pointer_delta(const volatile void* left,
 352                             const volatile void* right,
 353                             size_t element_size) {
 354   return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;
 355 }
 356 
 357 // A version specialized for HeapWord*'s.
 358 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {
 359   return pointer_delta(left, right, sizeof(HeapWord));
 360 }
 361 // A version specialized for MetaWord*'s.
 362 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) {
 363   return pointer_delta(left, right, sizeof(MetaWord));
 364 }
 365 
 366 //
 367 // ANSI C++ does not allow casting from one pointer type to a function pointer
 368 // directly without at best a warning. This macro accomplishes it silently
 369 // In every case that is present at this point the value be cast is a pointer
 370 // to a C linkage function. In some case the type used for the cast reflects
 371 // that linkage and a picky compiler would not complain. In other cases because
 372 // there is no convenient place to place a typedef with extern C linkage (i.e
 373 // a platform dependent header file) it doesn't. At this point no compiler seems
 374 // picky enough to catch these instances (which are few). It is possible that
 375 // using templates could fix these for all cases. This use of templates is likely
 376 // so far from the middle of the road that it is likely to be problematic in
 377 // many C++ compilers.
 378 //
 379 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value))
 380 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((address_word)(func_ptr)))
 381 
 382 // Unsigned byte types for os and stream.hpp
 383 
 384 // Unsigned one, two, four and eigth byte quantities used for describing
 385 // the .class file format. See JVM book chapter 4.
 386 
 387 typedef jubyte  u1;
 388 typedef jushort u2;
 389 typedef juint   u4;
 390 typedef julong  u8;
 391 
 392 const jubyte  max_jubyte  = (jubyte)-1;  // 0xFF       largest jubyte
 393 const jushort max_jushort = (jushort)-1; // 0xFFFF     largest jushort
 394 const juint   max_juint   = (juint)-1;   // 0xFFFFFFFF largest juint
 395 const julong  max_julong  = (julong)-1;  // 0xFF....FF largest julong
 396 
 397 typedef jbyte  s1;
 398 typedef jshort s2;
 399 typedef jint   s4;
 400 typedef jlong  s8;
 401 
 402 const jbyte min_jbyte = -(1 << 7);       // smallest jbyte
 403 const jbyte max_jbyte = (1 << 7) - 1;    // largest jbyte
 404 const jshort min_jshort = -(1 << 15);    // smallest jshort
 405 const jshort max_jshort = (1 << 15) - 1; // largest jshort
 406 
 407 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
 408 const jint max_jint = (juint)min_jint - 1;                     // 0x7FFFFFFF == largest jint
 409 
 410 //----------------------------------------------------------------------------------------------------
 411 // JVM spec restrictions
 412 
 413 const int max_method_code_size = 64*K - 1;  // JVM spec, 2nd ed. section 4.8.1 (p.134)
 414 
 415 //----------------------------------------------------------------------------------------------------
 416 // Default and minimum StringTable and SymbolTable size values
 417 // Must be a power of 2
 418 
 419 const size_t defaultStringTableSize = NOT_LP64(1024) LP64_ONLY(65536);
 420 const size_t minimumStringTableSize = 128;
 421 
 422 const size_t defaultSymbolTableSize = 32768; // 2^15
 423 const size_t minimumSymbolTableSize = 1024;
 424 
 425 
 426 //----------------------------------------------------------------------------------------------------
 427 // HotSwap - for JVMTI   aka Class File Replacement and PopFrame
 428 //
 429 // Determines whether on-the-fly class replacement and frame popping are enabled.
 430 
 431 #define HOTSWAP
 432 
 433 //----------------------------------------------------------------------------------------------------
 434 // Object alignment, in units of HeapWords.
 435 //
 436 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and
 437 // reference fields can be naturally aligned.
 438 
 439 extern int MinObjAlignment;
 440 extern int MinObjAlignmentInBytes;
 441 extern int MinObjAlignmentInBytesMask;
 442 
 443 extern int LogMinObjAlignment;
 444 extern int LogMinObjAlignmentInBytes;
 445 
 446 const int LogKlassAlignmentInBytes = 3;
 447 const int LogKlassAlignment        = LogKlassAlignmentInBytes - LogHeapWordSize;
 448 const int KlassAlignmentInBytes    = 1 << LogKlassAlignmentInBytes;
 449 const int KlassAlignment           = KlassAlignmentInBytes / HeapWordSize;
 450 
 451 // Maximal size of heap where unscaled compression can be used. Also upper bound
 452 // for heap placement: 4GB.
 453 const  uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
 454 // Maximal size of heap where compressed oops can be used. Also upper bound for heap
 455 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes.
 456 extern uint64_t OopEncodingHeapMax;
 457 
 458 // Maximal size of compressed class space. Above this limit compression is not possible.
 459 // Also upper bound for placement of zero based class space. (Class space is further limited
 460 // to be < 3G, see arguments.cpp.)
 461 const  uint64_t KlassEncodingMetaspaceMax = (uint64_t(max_juint) + 1) << LogKlassAlignmentInBytes;
 462 
 463 // Machine dependent stuff
 464 
 465 // The maximum size of the code cache.  Can be overridden by targets.
 466 #define CODE_CACHE_SIZE_LIMIT (2*G)
 467 // Allow targets to reduce the default size of the code cache.
 468 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT
 469 
 470 #include CPU_HEADER(globalDefinitions)
 471 
 472 // To assure the IRIW property on processors that are not multiple copy
 473 // atomic, sync instructions must be issued between volatile reads to
 474 // assure their ordering, instead of after volatile stores.
 475 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models"
 476 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge)
 477 #ifdef CPU_NOT_MULTIPLE_COPY_ATOMIC
 478 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = true;
 479 #else
 480 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false;
 481 #endif
 482 
 483 // The expected size in bytes of a cache line, used to pad data structures.
 484 #ifndef DEFAULT_CACHE_LINE_SIZE
 485   #define DEFAULT_CACHE_LINE_SIZE 64
 486 #endif
 487 
 488 
 489 //----------------------------------------------------------------------------------------------------
 490 // Utility macros for compilers
 491 // used to silence compiler warnings
 492 
 493 #define Unused_Variable(var) var
 494 
 495 
 496 //----------------------------------------------------------------------------------------------------
 497 // Miscellaneous
 498 
 499 // 6302670 Eliminate Hotspot __fabsf dependency
 500 // All fabs() callers should call this function instead, which will implicitly
 501 // convert the operand to double, avoiding a dependency on __fabsf which
 502 // doesn't exist in early versions of Solaris 8.
 503 inline double fabsd(double value) {
 504   return fabs(value);
 505 }
 506 
 507 // Returns numerator/denominator as percentage value from 0 to 100. If denominator
 508 // is zero, return 0.0.
 509 template<typename T>
 510 inline double percent_of(T numerator, T denominator) {
 511   return denominator != 0 ? (double)numerator / denominator * 100.0 : 0.0;
 512 }
 513 
 514 //----------------------------------------------------------------------------------------------------
 515 // Special casts
 516 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern
 517 typedef union {
 518   jfloat f;
 519   jint i;
 520 } FloatIntConv;
 521 
 522 typedef union {
 523   jdouble d;
 524   jlong l;
 525   julong ul;
 526 } DoubleLongConv;
 527 
 528 inline jint    jint_cast    (jfloat  x)  { return ((FloatIntConv*)&x)->i; }
 529 inline jfloat  jfloat_cast  (jint    x)  { return ((FloatIntConv*)&x)->f; }
 530 
 531 inline jlong   jlong_cast   (jdouble x)  { return ((DoubleLongConv*)&x)->l;  }
 532 inline julong  julong_cast  (jdouble x)  { return ((DoubleLongConv*)&x)->ul; }
 533 inline jdouble jdouble_cast (jlong   x)  { return ((DoubleLongConv*)&x)->d;  }
 534 
 535 inline jint low (jlong value)                    { return jint(value); }
 536 inline jint high(jlong value)                    { return jint(value >> 32); }
 537 
 538 // the fancy casts are a hopefully portable way
 539 // to do unsigned 32 to 64 bit type conversion
 540 inline void set_low (jlong* value, jint low )    { *value &= (jlong)0xffffffff << 32;
 541                                                    *value |= (jlong)(julong)(juint)low; }
 542 
 543 inline void set_high(jlong* value, jint high)    { *value &= (jlong)(julong)(juint)0xffffffff;
 544                                                    *value |= (jlong)high       << 32; }
 545 
 546 inline jlong jlong_from(jint h, jint l) {
 547   jlong result = 0; // initialization to avoid warning
 548   set_high(&result, h);
 549   set_low(&result,  l);
 550   return result;
 551 }
 552 
 553 union jlong_accessor {
 554   jint  words[2];
 555   jlong long_value;
 556 };
 557 
 558 void basic_types_init(); // cannot define here; uses assert
 559 
 560 
 561 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 562 enum BasicType {
 563   T_BOOLEAN     =  4,
 564   T_CHAR        =  5,
 565   T_FLOAT       =  6,
 566   T_DOUBLE      =  7,
 567   T_BYTE        =  8,
 568   T_SHORT       =  9,
 569   T_INT         = 10,
 570   T_LONG        = 11,
 571   T_OBJECT      = 12,
 572   T_ARRAY       = 13,
 573   T_VOID        = 14,
 574   T_ADDRESS     = 15,
 575   T_NARROWOOP   = 16,
 576   T_METADATA    = 17,
 577   T_NARROWKLASS = 18,
 578   T_CONFLICT    = 19, // for stack value type with conflicting contents
 579   T_ILLEGAL     = 99
 580 };
 581 
 582 inline bool is_java_primitive(BasicType t) {
 583   return T_BOOLEAN <= t && t <= T_LONG;
 584 }
 585 
 586 inline bool is_subword_type(BasicType t) {
 587   // these guys are processed exactly like T_INT in calling sequences:
 588   return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);
 589 }
 590 
 591 inline bool is_signed_subword_type(BasicType t) {
 592   return (t == T_BYTE || t == T_SHORT);
 593 }
 594 
 595 inline bool is_reference_type(BasicType t) {
 596   return (t == T_OBJECT || t == T_ARRAY);
 597 }
 598 
 599 // Convert a char from a classfile signature to a BasicType
 600 inline BasicType char2type(char c) {
 601   switch( c ) {
 602   case 'B': return T_BYTE;
 603   case 'C': return T_CHAR;
 604   case 'D': return T_DOUBLE;
 605   case 'F': return T_FLOAT;
 606   case 'I': return T_INT;
 607   case 'J': return T_LONG;
 608   case 'S': return T_SHORT;
 609   case 'Z': return T_BOOLEAN;
 610   case 'V': return T_VOID;
 611   case 'L': return T_OBJECT;
 612   case '[': return T_ARRAY;
 613   }
 614   return T_ILLEGAL;
 615 }
 616 
 617 extern char type2char_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 618 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }
 619 extern int type2size[T_CONFLICT+1];         // Map BasicType to result stack elements
 620 extern const char* type2name_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 621 inline const char* type2name(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2name_tab[t] : NULL; }
 622 extern BasicType name2type(const char* name);
 623 
 624 // Auxiliary math routines
 625 // least common multiple
 626 extern size_t lcm(size_t a, size_t b);
 627 
 628 
 629 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 630 enum BasicTypeSize {
 631   T_BOOLEAN_size     = 1,
 632   T_CHAR_size        = 1,
 633   T_FLOAT_size       = 1,
 634   T_DOUBLE_size      = 2,
 635   T_BYTE_size        = 1,
 636   T_SHORT_size       = 1,
 637   T_INT_size         = 1,
 638   T_LONG_size        = 2,
 639   T_OBJECT_size      = 1,
 640   T_ARRAY_size       = 1,
 641   T_NARROWOOP_size   = 1,
 642   T_NARROWKLASS_size = 1,
 643   T_VOID_size        = 0
 644 };
 645 
 646 
 647 // maps a BasicType to its instance field storage type:
 648 // all sub-word integral types are widened to T_INT
 649 extern BasicType type2field[T_CONFLICT+1];
 650 extern BasicType type2wfield[T_CONFLICT+1];
 651 
 652 
 653 // size in bytes
 654 enum ArrayElementSize {
 655   T_BOOLEAN_aelem_bytes     = 1,
 656   T_CHAR_aelem_bytes        = 2,
 657   T_FLOAT_aelem_bytes       = 4,
 658   T_DOUBLE_aelem_bytes      = 8,
 659   T_BYTE_aelem_bytes        = 1,
 660   T_SHORT_aelem_bytes       = 2,
 661   T_INT_aelem_bytes         = 4,
 662   T_LONG_aelem_bytes        = 8,
 663 #ifdef _LP64
 664   T_OBJECT_aelem_bytes      = 8,
 665   T_ARRAY_aelem_bytes       = 8,
 666 #else
 667   T_OBJECT_aelem_bytes      = 4,
 668   T_ARRAY_aelem_bytes       = 4,
 669 #endif
 670   T_NARROWOOP_aelem_bytes   = 4,
 671   T_NARROWKLASS_aelem_bytes = 4,
 672   T_VOID_aelem_bytes        = 0
 673 };
 674 
 675 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element
 676 #ifdef ASSERT
 677 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts
 678 #else
 679 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; }
 680 #endif
 681 
 682 
 683 // JavaValue serves as a container for arbitrary Java values.
 684 
 685 class JavaValue {
 686 
 687  public:
 688   typedef union JavaCallValue {
 689     jfloat   f;
 690     jdouble  d;
 691     jint     i;
 692     jlong    l;
 693     jobject  h;
 694   } JavaCallValue;
 695 
 696  private:
 697   BasicType _type;
 698   JavaCallValue _value;
 699 
 700  public:
 701   JavaValue(BasicType t = T_ILLEGAL) { _type = t; }
 702 
 703   JavaValue(jfloat value) {
 704     _type    = T_FLOAT;
 705     _value.f = value;
 706   }
 707 
 708   JavaValue(jdouble value) {
 709     _type    = T_DOUBLE;
 710     _value.d = value;
 711   }
 712 
 713  jfloat get_jfloat() const { return _value.f; }
 714  jdouble get_jdouble() const { return _value.d; }
 715  jint get_jint() const { return _value.i; }
 716  jlong get_jlong() const { return _value.l; }
 717  jobject get_jobject() const { return _value.h; }
 718  JavaCallValue* get_value_addr() { return &_value; }
 719  BasicType get_type() const { return _type; }
 720 
 721  void set_jfloat(jfloat f) { _value.f = f;}
 722  void set_jdouble(jdouble d) { _value.d = d;}
 723  void set_jint(jint i) { _value.i = i;}
 724  void set_jlong(jlong l) { _value.l = l;}
 725  void set_jobject(jobject h) { _value.h = h;}
 726  void set_type(BasicType t) { _type = t; }
 727 
 728  jboolean get_jboolean() const { return (jboolean) (_value.i);}
 729  jbyte get_jbyte() const { return (jbyte) (_value.i);}
 730  jchar get_jchar() const { return (jchar) (_value.i);}
 731  jshort get_jshort() const { return (jshort) (_value.i);}
 732 
 733 };
 734 
 735 
 736 #define STACK_BIAS      0
 737 // V9 Sparc CPU's running in 64 Bit mode use a stack bias of 7ff
 738 // in order to extend the reach of the stack pointer.
 739 #if defined(SPARC) && defined(_LP64)
 740 #undef STACK_BIAS
 741 #define STACK_BIAS      0x7ff
 742 #endif
 743 
 744 
 745 // TosState describes the top-of-stack state before and after the execution of
 746 // a bytecode or method. The top-of-stack value may be cached in one or more CPU
 747 // registers. The TosState corresponds to the 'machine representation' of this cached
 748 // value. There's 4 states corresponding to the JAVA types int, long, float & double
 749 // as well as a 5th state in case the top-of-stack value is actually on the top
 750 // of stack (in memory) and thus not cached. The atos state corresponds to the itos
 751 // state when it comes to machine representation but is used separately for (oop)
 752 // type specific operations (e.g. verification code).
 753 
 754 enum TosState {         // describes the tos cache contents
 755   btos = 0,             // byte, bool tos cached
 756   ztos = 1,             // byte, bool tos cached
 757   ctos = 2,             // char tos cached
 758   stos = 3,             // short tos cached
 759   itos = 4,             // int tos cached
 760   ltos = 5,             // long tos cached
 761   ftos = 6,             // float tos cached
 762   dtos = 7,             // double tos cached
 763   atos = 8,             // object cached
 764   vtos = 9,             // tos not cached
 765   number_of_states,
 766   ilgl                  // illegal state: should not occur
 767 };
 768 
 769 
 770 inline TosState as_TosState(BasicType type) {
 771   switch (type) {
 772     case T_BYTE   : return btos;
 773     case T_BOOLEAN: return ztos;
 774     case T_CHAR   : return ctos;
 775     case T_SHORT  : return stos;
 776     case T_INT    : return itos;
 777     case T_LONG   : return ltos;
 778     case T_FLOAT  : return ftos;
 779     case T_DOUBLE : return dtos;
 780     case T_VOID   : return vtos;
 781     case T_ARRAY  : // fall through
 782     case T_OBJECT : return atos;
 783     default       : return ilgl;
 784   }
 785 }
 786 
 787 inline BasicType as_BasicType(TosState state) {
 788   switch (state) {
 789     case btos : return T_BYTE;
 790     case ztos : return T_BOOLEAN;
 791     case ctos : return T_CHAR;
 792     case stos : return T_SHORT;
 793     case itos : return T_INT;
 794     case ltos : return T_LONG;
 795     case ftos : return T_FLOAT;
 796     case dtos : return T_DOUBLE;
 797     case atos : return T_OBJECT;
 798     case vtos : return T_VOID;
 799     default   : return T_ILLEGAL;
 800   }
 801 }
 802 
 803 
 804 // Helper function to convert BasicType info into TosState
 805 // Note: Cannot define here as it uses global constant at the time being.
 806 TosState as_TosState(BasicType type);
 807 
 808 
 809 // JavaThreadState keeps track of which part of the code a thread is executing in. This
 810 // information is needed by the safepoint code.
 811 //
 812 // There are 4 essential states:
 813 //
 814 //  _thread_new         : Just started, but not executed init. code yet (most likely still in OS init code)
 815 //  _thread_in_native   : In native code. This is a safepoint region, since all oops will be in jobject handles
 816 //  _thread_in_vm       : Executing in the vm
 817 //  _thread_in_Java     : Executing either interpreted or compiled Java code (or could be in a stub)
 818 //
 819 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in
 820 // a transition from one state to another. These extra states makes it possible for the safepoint code to
 821 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.
 822 //
 823 // Given a state, the xxxx_trans state can always be found by adding 1.
 824 //
 825 enum JavaThreadState {
 826   _thread_uninitialized     =  0, // should never happen (missing initialization)
 827   _thread_new               =  2, // just starting up, i.e., in process of being initialized
 828   _thread_new_trans         =  3, // corresponding transition state (not used, included for completness)
 829   _thread_in_native         =  4, // running in native code
 830   _thread_in_native_trans   =  5, // corresponding transition state
 831   _thread_in_vm             =  6, // running in VM
 832   _thread_in_vm_trans       =  7, // corresponding transition state
 833   _thread_in_Java           =  8, // running in Java or in stub code
 834   _thread_in_Java_trans     =  9, // corresponding transition state (not used, included for completness)
 835   _thread_blocked           = 10, // blocked in vm
 836   _thread_blocked_trans     = 11, // corresponding transition state
 837   _thread_max_state         = 12  // maximum thread state+1 - used for statistics allocation
 838 };
 839 
 840 
 841 
 842 //----------------------------------------------------------------------------------------------------
 843 // 'Forward' declarations of frequently used classes
 844 // (in order to reduce interface dependencies & reduce
 845 // number of unnecessary compilations after changes)
 846 
 847 class ClassFileStream;
 848 
 849 class Event;
 850 
 851 class Thread;
 852 class  VMThread;
 853 class  JavaThread;
 854 class Threads;
 855 
 856 class VM_Operation;
 857 class VMOperationQueue;
 858 
 859 class CodeBlob;
 860 class  CompiledMethod;
 861 class   nmethod;
 862 class RuntimeBlob;
 863 class  OSRAdapter;
 864 class  I2CAdapter;
 865 class  C2IAdapter;
 866 class CompiledIC;
 867 class relocInfo;
 868 class ScopeDesc;
 869 class PcDesc;
 870 
 871 class Recompiler;
 872 class Recompilee;
 873 class RecompilationPolicy;
 874 class RFrame;
 875 class  CompiledRFrame;
 876 class  InterpretedRFrame;
 877 
 878 class vframe;
 879 class   javaVFrame;
 880 class     interpretedVFrame;
 881 class     compiledVFrame;
 882 class     deoptimizedVFrame;
 883 class   externalVFrame;
 884 class     entryVFrame;
 885 
 886 class RegisterMap;
 887 
 888 class Mutex;
 889 class Monitor;
 890 class BasicLock;
 891 class BasicObjectLock;
 892 
 893 class PeriodicTask;
 894 
 895 class JavaCallWrapper;
 896 
 897 class   oopDesc;
 898 class   metaDataOopDesc;
 899 
 900 class NativeCall;
 901 
 902 class zone;
 903 
 904 class StubQueue;
 905 
 906 class outputStream;
 907 
 908 class ResourceArea;
 909 
 910 class DebugInformationRecorder;
 911 class ScopeValue;
 912 class CompressedStream;
 913 class   DebugInfoReadStream;
 914 class   DebugInfoWriteStream;
 915 class LocationValue;
 916 class ConstantValue;
 917 class IllegalValue;
 918 
 919 class MonitorArray;
 920 
 921 class MonitorInfo;
 922 
 923 class OffsetClosure;
 924 class OopMapCache;
 925 class InterpreterOopMap;
 926 class OopMapCacheEntry;
 927 class OSThread;
 928 
 929 typedef int (*OSThreadStartFunc)(void*);
 930 
 931 class Space;
 932 
 933 class JavaValue;
 934 class methodHandle;
 935 class JavaCallArguments;
 936 
 937 //----------------------------------------------------------------------------------------------------
 938 // Special constants for debugging
 939 
 940 const jint     badInt           = -3;                       // generic "bad int" value
 941 const intptr_t badAddressVal    = -2;                       // generic "bad address" value
 942 const intptr_t badOopVal        = -1;                       // generic "bad oop" value
 943 const intptr_t badHeapOopVal    = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC
 944 const int      badStackSegVal   = 0xCA;                     // value used to zap stack segments
 945 const int      badHandleValue   = 0xBC;                     // value used to zap vm handle area
 946 const int      badResourceValue = 0xAB;                     // value used to zap resource area
 947 const int      freeBlockPad     = 0xBA;                     // value used to pad freed blocks.
 948 const int      uninitBlockPad   = 0xF1;                     // value used to zap newly malloc'd blocks.
 949 const juint    uninitMetaWordVal= 0xf7f7f7f7;               // value used to zap newly allocated metachunk
 950 const juint    badHeapWordVal   = 0xBAADBABE;               // value used to zap heap after GC
 951 const juint    badMetaWordVal   = 0xBAADFADE;               // value used to zap metadata heap after GC
 952 const int      badCodeHeapNewVal= 0xCC;                     // value used to zap Code heap at allocation
 953 const int      badCodeHeapFreeVal = 0xDD;                   // value used to zap Code heap at deallocation
 954 
 955 
 956 // (These must be implemented as #defines because C++ compilers are
 957 // not obligated to inline non-integral constants!)
 958 #define       badAddress        ((address)::badAddressVal)
 959 #define       badOop            (cast_to_oop(::badOopVal))
 960 #define       badHeapWord       (::badHeapWordVal)
 961 
 962 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)
 963 #define TASKQUEUE_SIZE (NOT_LP64(1<<14) LP64_ONLY(1<<17))
 964 
 965 //----------------------------------------------------------------------------------------------------
 966 // Utility functions for bitfield manipulations
 967 
 968 const intptr_t AllBits    = ~0; // all bits set in a word
 969 const intptr_t NoBits     =  0; // no bits set in a word
 970 const jlong    NoLongBits =  0; // no bits set in a long
 971 const intptr_t OneBit     =  1; // only right_most bit set in a word
 972 
 973 // get a word with the n.th or the right-most or left-most n bits set
 974 // (note: #define used only so that they can be used in enum constant definitions)
 975 #define nth_bit(n)        (((n) >= BitsPerWord) ? 0 : (OneBit << (n)))
 976 #define right_n_bits(n)   (nth_bit(n) - 1)
 977 #define left_n_bits(n)    (right_n_bits(n) << (((n) >= BitsPerWord) ? 0 : (BitsPerWord - (n))))
 978 
 979 // bit-operations using a mask m
 980 inline void   set_bits    (intptr_t& x, intptr_t m) { x |= m; }
 981 inline void clear_bits    (intptr_t& x, intptr_t m) { x &= ~m; }
 982 inline intptr_t mask_bits      (intptr_t  x, intptr_t m) { return x & m; }
 983 inline jlong    mask_long_bits (jlong     x, jlong    m) { return x & m; }
 984 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }
 985 
 986 // bit-operations using the n.th bit
 987 inline void    set_nth_bit(intptr_t& x, int n) { set_bits  (x, nth_bit(n)); }
 988 inline void  clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }
 989 inline bool is_set_nth_bit(intptr_t  x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }
 990 
 991 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)
 992 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {
 993   return mask_bits(x >> start_bit_no, right_n_bits(field_length));
 994 }
 995 
 996 
 997 //----------------------------------------------------------------------------------------------------
 998 // Utility functions for integers
 999 
1000 // Avoid use of global min/max macros which may cause unwanted double
1001 // evaluation of arguments.
1002 #ifdef max
1003 #undef max
1004 #endif
1005 
1006 #ifdef min
1007 #undef min
1008 #endif
1009 
1010 // It is necessary to use templates here. Having normal overloaded
1011 // functions does not work because it is necessary to provide both 32-
1012 // and 64-bit overloaded functions, which does not work, and having
1013 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)
1014 // will be even more error-prone than macros.
1015 template<class T> inline T MAX2(T a, T b)           { return (a > b) ? a : b; }
1016 template<class T> inline T MIN2(T a, T b)           { return (a < b) ? a : b; }
1017 template<class T> inline T MAX3(T a, T b, T c)      { return MAX2(MAX2(a, b), c); }
1018 template<class T> inline T MIN3(T a, T b, T c)      { return MIN2(MIN2(a, b), c); }
1019 template<class T> inline T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }
1020 template<class T> inline T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }
1021 
1022 template<class T> inline T ABS(T x)                 { return (x > 0) ? x : -x; }
1023 
1024 // true if x is a power of 2, false otherwise
1025 inline bool is_power_of_2(intptr_t x) {
1026   return ((x != NoBits) && (mask_bits(x, x - 1) == NoBits));
1027 }
1028 
1029 // long version of is_power_of_2
1030 inline bool is_power_of_2_long(jlong x) {
1031   return ((x != NoLongBits) && (mask_long_bits(x, x - 1) == NoLongBits));
1032 }
1033 
1034 // Returns largest i such that 2^i <= x.
1035 // If x < 0, the function returns 31 on a 32-bit machine and 63 on a 64-bit machine.
1036 // If x == 0, the function returns -1.
1037 inline int log2_intptr(uintptr_t x) {
1038   int i = -1;
1039   uintptr_t p = 1;
1040   while (p != 0 && p <= x) {
1041     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
1042     i++; p *= 2;
1043   }
1044   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))
1045   // If p = 0, overflow has occurred and i = 31 or i = 63 (depending on the machine word size).
1046   return i;
1047 }
1048 
1049 //* largest i such that 2^i <= x
1050 //  A negative value of 'x' will return '63'
1051 inline int log2_long(unsigned long x) {
1052   int i = -1;
1053   julong p =  1;
1054   while (p != 0 && p <= x) {
1055     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
1056     i++; p *= 2;
1057   }
1058   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))
1059   // (if p = 0 then overflow occurred and i = 63)
1060   return i;
1061 }
1062 
1063 inline int log2_intptr(intptr_t x) {
1064   return log2_intptr((uintptr_t)x);
1065 }
1066 
1067 #ifdef _LP64
1068 inline int log2_intptr(int x) {
1069   return log2_intptr((uintptr_t)x);
1070 }
1071 
1072 inline int log2_intptr(uint x) {
1073   return log2_intptr((uintptr_t)x);
1074 }
1075 #endif
1076 
1077 inline int log2_long(jlong x) {
1078   return log2_long((unsigned long)x);
1079 }
1080 
1081 //* the argument must be exactly a power of 2
1082 inline int exact_log2(intptr_t x) {
1083   assert(is_power_of_2(x), "x must be a power of 2: " INTPTR_FORMAT, x);
1084   return log2_intptr(x);
1085 }
1086 
1087 //* the argument must be exactly a power of 2
1088 inline int exact_log2_long(jlong x) {
1089   assert(is_power_of_2_long(x), "x must be a power of 2: " JLONG_FORMAT, x);
1090   return log2_long(x);
1091 }
1092 
1093 inline bool is_odd (intx x) { return x & 1;      }
1094 inline bool is_even(intx x) { return !is_odd(x); }
1095 
1096 // abs methods which cannot overflow and so are well-defined across
1097 // the entire domain of integer types.
1098 static inline unsigned int uabs(unsigned int n) {
1099   union {
1100     unsigned int result;
1101     int value;
1102   };
1103   result = n;
1104   if (value < 0) result = 0-result;
1105   return result;
1106 }
1107 static inline unsigned long uabs(unsigned long n) {
1108   union {
1109     unsigned long result;
1110     long value;
1111   };
1112   result = n;
1113   if (value < 0) result = 0-result;
1114   return result;
1115 }
1116 static inline unsigned long uabs(jlong n) { return uabs((unsigned long)n); }
1117 static inline unsigned int uabs(int n) { return uabs((unsigned int)n); }
1118 
1119 // "to" should be greater than "from."
1120 inline intx byte_size(void* from, void* to) {
1121   return (address)to - (address)from;
1122 }
1123 
1124 //----------------------------------------------------------------------------------------------------
1125 // Avoid non-portable casts with these routines (DEPRECATED)
1126 
1127 // NOTE: USE Bytes class INSTEAD WHERE POSSIBLE
1128 //       Bytes is optimized machine-specifically and may be much faster then the portable routines below.
1129 
1130 // Given sequence of four bytes, build into a 32-bit word
1131 // following the conventions used in class files.
1132 // On the 386, this could be realized with a simple address cast.
1133 //
1134 
1135 // This routine takes eight bytes:
1136 inline u8 build_u8_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {
1137   return  (( u8(c1) << 56 )  &  ( u8(0xff) << 56 ))
1138        |  (( u8(c2) << 48 )  &  ( u8(0xff) << 48 ))
1139        |  (( u8(c3) << 40 )  &  ( u8(0xff) << 40 ))
1140        |  (( u8(c4) << 32 )  &  ( u8(0xff) << 32 ))
1141        |  (( u8(c5) << 24 )  &  ( u8(0xff) << 24 ))
1142        |  (( u8(c6) << 16 )  &  ( u8(0xff) << 16 ))
1143        |  (( u8(c7) <<  8 )  &  ( u8(0xff) <<  8 ))
1144        |  (( u8(c8) <<  0 )  &  ( u8(0xff) <<  0 ));
1145 }
1146 
1147 // This routine takes four bytes:
1148 inline u4 build_u4_from( u1 c1, u1 c2, u1 c3, u1 c4 ) {
1149   return  (( u4(c1) << 24 )  &  0xff000000)
1150        |  (( u4(c2) << 16 )  &  0x00ff0000)
1151        |  (( u4(c3) <<  8 )  &  0x0000ff00)
1152        |  (( u4(c4) <<  0 )  &  0x000000ff);
1153 }
1154 
1155 // And this one works if the four bytes are contiguous in memory:
1156 inline u4 build_u4_from( u1* p ) {
1157   return  build_u4_from( p[0], p[1], p[2], p[3] );
1158 }
1159 
1160 // Ditto for two-byte ints:
1161 inline u2 build_u2_from( u1 c1, u1 c2 ) {
1162   return  u2((( u2(c1) <<  8 )  &  0xff00)
1163           |  (( u2(c2) <<  0 )  &  0x00ff));
1164 }
1165 
1166 // And this one works if the two bytes are contiguous in memory:
1167 inline u2 build_u2_from( u1* p ) {
1168   return  build_u2_from( p[0], p[1] );
1169 }
1170 
1171 // Ditto for floats:
1172 inline jfloat build_float_from( u1 c1, u1 c2, u1 c3, u1 c4 ) {
1173   u4 u = build_u4_from( c1, c2, c3, c4 );
1174   return  *(jfloat*)&u;
1175 }
1176 
1177 inline jfloat build_float_from( u1* p ) {
1178   u4 u = build_u4_from( p );
1179   return  *(jfloat*)&u;
1180 }
1181 
1182 
1183 // now (64-bit) longs
1184 
1185 inline jlong build_long_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {
1186   return  (( jlong(c1) << 56 )  &  ( jlong(0xff) << 56 ))
1187        |  (( jlong(c2) << 48 )  &  ( jlong(0xff) << 48 ))
1188        |  (( jlong(c3) << 40 )  &  ( jlong(0xff) << 40 ))
1189        |  (( jlong(c4) << 32 )  &  ( jlong(0xff) << 32 ))
1190        |  (( jlong(c5) << 24 )  &  ( jlong(0xff) << 24 ))
1191        |  (( jlong(c6) << 16 )  &  ( jlong(0xff) << 16 ))
1192        |  (( jlong(c7) <<  8 )  &  ( jlong(0xff) <<  8 ))
1193        |  (( jlong(c8) <<  0 )  &  ( jlong(0xff) <<  0 ));
1194 }
1195 
1196 inline jlong build_long_from( u1* p ) {
1197   return  build_long_from( p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7] );
1198 }
1199 
1200 
1201 // Doubles, too!
1202 inline jdouble build_double_from( u1 c1, u1 c2, u1 c3, u1 c4, u1 c5, u1 c6, u1 c7, u1 c8 ) {
1203   jlong u = build_long_from( c1, c2, c3, c4, c5, c6, c7, c8 );
1204   return  *(jdouble*)&u;
1205 }
1206 
1207 inline jdouble build_double_from( u1* p ) {
1208   jlong u = build_long_from( p );
1209   return  *(jdouble*)&u;
1210 }
1211 
1212 
1213 // Portable routines to go the other way:
1214 
1215 inline void explode_short_to( u2 x, u1& c1, u1& c2 ) {
1216   c1 = u1(x >> 8);
1217   c2 = u1(x);
1218 }
1219 
1220 inline void explode_short_to( u2 x, u1* p ) {
1221   explode_short_to( x, p[0], p[1]);
1222 }
1223 
1224 inline void explode_int_to( u4 x, u1& c1, u1& c2, u1& c3, u1& c4 ) {
1225   c1 = u1(x >> 24);
1226   c2 = u1(x >> 16);
1227   c3 = u1(x >>  8);
1228   c4 = u1(x);
1229 }
1230 
1231 inline void explode_int_to( u4 x, u1* p ) {
1232   explode_int_to( x, p[0], p[1], p[2], p[3]);
1233 }
1234 
1235 
1236 // Pack and extract shorts to/from ints:
1237 
1238 inline int extract_low_short_from_int(jint x) {
1239   return x & 0xffff;
1240 }
1241 
1242 inline int extract_high_short_from_int(jint x) {
1243   return (x >> 16) & 0xffff;
1244 }
1245 
1246 inline int build_int_from_shorts( jushort low, jushort high ) {
1247   return ((int)((unsigned int)high << 16) | (unsigned int)low);
1248 }
1249 
1250 // Convert pointer to intptr_t, for use in printing pointers.
1251 inline intptr_t p2i(const void * p) {
1252   return (intptr_t) p;
1253 }
1254 
1255 // swap a & b
1256 template<class T> static void swap(T& a, T& b) {
1257   T tmp = a;
1258   a = b;
1259   b = tmp;
1260 }
1261 
1262 #define ARRAY_SIZE(array) (sizeof(array)/sizeof((array)[0]))
1263 
1264 //----------------------------------------------------------------------------------------------------
1265 // Sum and product which can never overflow: they wrap, just like the
1266 // Java operations.  Note that we don't intend these to be used for
1267 // general-purpose arithmetic: their purpose is to emulate Java
1268 // operations.
1269 
1270 // The goal of this code to avoid undefined or implementation-defined
1271 // behavior.  The use of an lvalue to reference cast is explicitly
1272 // permitted by Lvalues and rvalues [basic.lval].  [Section 3.10 Para
1273 // 15 in C++03]
1274 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE)  \
1275 inline TYPE NAME (TYPE in1, TYPE in2) {                 \
1276   UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \
1277   ures OP ## = static_cast<UNSIGNED_TYPE>(in2);         \
1278   return reinterpret_cast<TYPE&>(ures);                 \
1279 }
1280 
1281 JAVA_INTEGER_OP(+, java_add, jint, juint)
1282 JAVA_INTEGER_OP(-, java_subtract, jint, juint)
1283 JAVA_INTEGER_OP(*, java_multiply, jint, juint)
1284 JAVA_INTEGER_OP(+, java_add, jlong, julong)
1285 JAVA_INTEGER_OP(-, java_subtract, jlong, julong)
1286 JAVA_INTEGER_OP(*, java_multiply, jlong, julong)
1287 
1288 #undef JAVA_INTEGER_OP
1289 
1290 // Dereference vptr
1291 // All C++ compilers that we know of have the vtbl pointer in the first
1292 // word.  If there are exceptions, this function needs to be made compiler
1293 // specific.
1294 static inline void* dereference_vptr(const void* addr) {
1295   return *(void**)addr;
1296 }
1297 
1298 //----------------------------------------------------------------------------------------------------
1299 // String type aliases used by command line flag declarations and
1300 // processing utilities.
1301 
1302 typedef const char* ccstr;
1303 typedef const char* ccstrlist;   // represents string arguments which accumulate
1304 
1305 //----------------------------------------------------------------------------------------------------
1306 // Default hash/equals functions used by ResourceHashtable and KVHashtable
1307 
1308 template<typename K> unsigned primitive_hash(const K& k) {
1309   unsigned hash = (unsigned)((uintptr_t)k);
1310   return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs
1311 }
1312 
1313 template<typename K> bool primitive_equals(const K& k0, const K& k1) {
1314   return k0 == k1;
1315 }
1316 
1317 
1318 #endif // SHARE_VM_UTILITIES_GLOBALDEFINITIONS_HPP