1 /*
   2  * Copyright (c) 1997, 2020, 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
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  22  *
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  24 
  25 #ifndef SHARE_UTILITIES_GLOBALDEFINITIONS_HPP
  26 #define SHARE_UTILITIES_GLOBALDEFINITIONS_HPP
  27 
  28 #include "utilities/compilerWarnings.hpp"
  29 #include "utilities/debug.hpp"
  30 #include "utilities/macros.hpp"
  31 
  32 // Get constants like JVM_T_CHAR and JVM_SIGNATURE_INT, before pulling in <jvm.h>.
  33 #include "classfile_constants.h"
  34 
  35 #include COMPILER_HEADER(utilities/globalDefinitions)
  36 
  37 // Defaults for macros that might be defined per compiler.
  38 #ifndef NOINLINE
  39 #define NOINLINE
  40 #endif
  41 #ifndef ALWAYSINLINE
  42 #define ALWAYSINLINE inline
  43 #endif
  44 
  45 #ifndef ATTRIBUTE_ALIGNED
  46 #define ATTRIBUTE_ALIGNED(x)
  47 #endif
  48 
  49 // These are #defines to selectively turn on/off the Print(Opto)Assembly
  50 // capabilities. Choices should be led by a tradeoff between
  51 // code size and improved supportability.
  52 // if PRINT_ASSEMBLY then PRINT_ABSTRACT_ASSEMBLY must be true as well
  53 // to have a fallback in case hsdis is not available.
  54 #if defined(PRODUCT)
  55   #define SUPPORT_ABSTRACT_ASSEMBLY
  56   #define SUPPORT_ASSEMBLY
  57   #undef  SUPPORT_OPTO_ASSEMBLY      // Can't activate. In PRODUCT, many dump methods are missing.
  58   #undef  SUPPORT_DATA_STRUCTS       // Of limited use. In PRODUCT, many print methods are empty.
  59 #else
  60   #define SUPPORT_ABSTRACT_ASSEMBLY
  61   #define SUPPORT_ASSEMBLY
  62   #define SUPPORT_OPTO_ASSEMBLY
  63   #define SUPPORT_DATA_STRUCTS
  64 #endif
  65 #if defined(SUPPORT_ASSEMBLY) && !defined(SUPPORT_ABSTRACT_ASSEMBLY)
  66   #define SUPPORT_ABSTRACT_ASSEMBLY
  67 #endif
  68 
  69 // This file holds all globally used constants & types, class (forward)
  70 // declarations and a few frequently used utility functions.
  71 
  72 // Declare the named class to be noncopyable.  This macro must be used in
  73 // a private part of the class's definition, followed by a semi-colon.
  74 // Doing so provides private declarations for the class's copy constructor
  75 // and assignment operator.  Because these operations are private, most
  76 // potential callers will fail to compile because they are inaccessible.
  77 // The operations intentionally lack a definition, to provoke link-time
  78 // failures for calls from contexts where they are accessible, e.g. from
  79 // within the class or from a friend of the class.
  80 // Note: The lack of definitions is still not completely bullet-proof, as
  81 // an apparent call might be optimized away by copy elision.
  82 // For C++11 the declarations should be changed to deleted definitions.
  83 #define NONCOPYABLE(C) C(C const&); C& operator=(C const&) /* next token must be ; */
  84 
  85 //----------------------------------------------------------------------------------------------------
  86 // Printf-style formatters for fixed- and variable-width types as pointers and
  87 // integers.  These are derived from the definitions in inttypes.h.  If the platform
  88 // doesn't provide appropriate definitions, they should be provided in
  89 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp)
  90 
  91 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false")
  92 
  93 // Format 32-bit quantities.
  94 #define INT32_FORMAT           "%" PRId32
  95 #define UINT32_FORMAT          "%" PRIu32
  96 #define INT32_FORMAT_W(width)  "%" #width PRId32
  97 #define UINT32_FORMAT_W(width) "%" #width PRIu32
  98 
  99 #define PTR32_FORMAT           "0x%08" PRIx32
 100 #define PTR32_FORMAT_W(width)  "0x%" #width PRIx32
 101 
 102 // Format 64-bit quantities.
 103 #define INT64_FORMAT           "%" PRId64
 104 #define UINT64_FORMAT          "%" PRIu64
 105 #define UINT64_FORMAT_X        "%" PRIx64
 106 #define INT64_FORMAT_W(width)  "%" #width PRId64
 107 #define UINT64_FORMAT_W(width) "%" #width PRIu64
 108 #define UINT64_FORMAT_X_W(width) "%" #width PRIx64
 109 
 110 #define PTR64_FORMAT           "0x%016" PRIx64
 111 
 112 // Format jlong, if necessary
 113 #ifndef JLONG_FORMAT
 114 #define JLONG_FORMAT           INT64_FORMAT
 115 #endif
 116 #ifndef JLONG_FORMAT_W
 117 #define JLONG_FORMAT_W(width)  INT64_FORMAT_W(width)
 118 #endif
 119 #ifndef JULONG_FORMAT
 120 #define JULONG_FORMAT          UINT64_FORMAT
 121 #endif
 122 #ifndef JULONG_FORMAT_X
 123 #define JULONG_FORMAT_X        UINT64_FORMAT_X
 124 #endif
 125 
 126 // Format pointers which change size between 32- and 64-bit.
 127 #ifdef  _LP64
 128 #define INTPTR_FORMAT "0x%016" PRIxPTR
 129 #define PTR_FORMAT    "0x%016" PRIxPTR
 130 #else   // !_LP64
 131 #define INTPTR_FORMAT "0x%08"  PRIxPTR
 132 #define PTR_FORMAT    "0x%08"  PRIxPTR
 133 #endif  // _LP64
 134 
 135 // Format pointers without leading zeros
 136 #define INTPTRNZ_FORMAT "0x%"  PRIxPTR
 137 
 138 #define INTPTR_FORMAT_W(width)   "%" #width PRIxPTR
 139 
 140 #define SSIZE_FORMAT             "%"   PRIdPTR
 141 #define SIZE_FORMAT              "%"   PRIuPTR
 142 #define SIZE_FORMAT_HEX          "0x%" PRIxPTR
 143 #define SSIZE_FORMAT_W(width)    "%"   #width PRIdPTR
 144 #define SIZE_FORMAT_W(width)     "%"   #width PRIuPTR
 145 #define SIZE_FORMAT_HEX_W(width) "0x%" #width PRIxPTR
 146 
 147 #define INTX_FORMAT           "%" PRIdPTR
 148 #define UINTX_FORMAT          "%" PRIuPTR
 149 #define INTX_FORMAT_W(width)  "%" #width PRIdPTR
 150 #define UINTX_FORMAT_W(width) "%" #width PRIuPTR
 151 
 152 //----------------------------------------------------------------------------------------------------
 153 // Constants
 154 
 155 const int LogBytesPerShort   = 1;
 156 const int LogBytesPerInt     = 2;
 157 #ifdef _LP64
 158 const int LogBytesPerWord    = 3;
 159 #else
 160 const int LogBytesPerWord    = 2;
 161 #endif
 162 const int LogBytesPerLong    = 3;
 163 
 164 const int BytesPerShort      = 1 << LogBytesPerShort;
 165 const int BytesPerInt        = 1 << LogBytesPerInt;
 166 const int BytesPerWord       = 1 << LogBytesPerWord;
 167 const int BytesPerLong       = 1 << LogBytesPerLong;
 168 
 169 const int LogBitsPerByte     = 3;
 170 const int LogBitsPerShort    = LogBitsPerByte + LogBytesPerShort;
 171 const int LogBitsPerInt      = LogBitsPerByte + LogBytesPerInt;
 172 const int LogBitsPerWord     = LogBitsPerByte + LogBytesPerWord;
 173 const int LogBitsPerLong     = LogBitsPerByte + LogBytesPerLong;
 174 
 175 const int BitsPerByte        = 1 << LogBitsPerByte;
 176 const int BitsPerShort       = 1 << LogBitsPerShort;
 177 const int BitsPerInt         = 1 << LogBitsPerInt;
 178 const int BitsPerWord        = 1 << LogBitsPerWord;
 179 const int BitsPerLong        = 1 << LogBitsPerLong;
 180 
 181 const int WordAlignmentMask  = (1 << LogBytesPerWord) - 1;
 182 const int LongAlignmentMask  = (1 << LogBytesPerLong) - 1;
 183 
 184 const int WordsPerLong       = 2;       // Number of stack entries for longs
 185 
 186 const int oopSize            = sizeof(char*); // Full-width oop
 187 extern int heapOopSize;                       // Oop within a java object
 188 const int wordSize           = sizeof(char*);
 189 const int longSize           = sizeof(jlong);
 190 const int jintSize           = sizeof(jint);
 191 const int size_tSize         = sizeof(size_t);
 192 
 193 const int BytesPerOop        = BytesPerWord;  // Full-width oop
 194 
 195 extern int LogBytesPerHeapOop;                // Oop within a java object
 196 extern int LogBitsPerHeapOop;
 197 extern int BytesPerHeapOop;
 198 extern int BitsPerHeapOop;
 199 
 200 const int BitsPerJavaInteger = 32;
 201 const int BitsPerJavaLong    = 64;
 202 const int BitsPerSize_t      = size_tSize * BitsPerByte;
 203 
 204 // Size of a char[] needed to represent a jint as a string in decimal.
 205 const int jintAsStringSize = 12;
 206 
 207 // An opaque type, so that HeapWord* can be a generic pointer into the heap.
 208 // We require that object sizes be measured in units of heap words (e.g.
 209 // pointer-sized values), so that given HeapWord* hw,
 210 //   hw += oop(hw)->foo();
 211 // works, where foo is a method (like size or scavenge) that returns the
 212 // object size.
 213 class HeapWordImpl;             // Opaque, never defined.
 214 typedef HeapWordImpl* HeapWord;
 215 
 216 // Analogous opaque struct for metadata allocated from metaspaces.
 217 class MetaWordImpl;             // Opaque, never defined.
 218 typedef MetaWordImpl* MetaWord;
 219 
 220 // HeapWordSize must be 2^LogHeapWordSize.
 221 const int HeapWordSize        = sizeof(HeapWord);
 222 #ifdef _LP64
 223 const int LogHeapWordSize     = 3;
 224 #else
 225 const int LogHeapWordSize     = 2;
 226 #endif
 227 const int HeapWordsPerLong    = BytesPerLong / HeapWordSize;
 228 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize;
 229 
 230 // The minimum number of native machine words necessary to contain "byte_size"
 231 // bytes.
 232 inline size_t heap_word_size(size_t byte_size) {
 233   return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize;
 234 }
 235 
 236 //-------------------------------------------
 237 // Constant for jlong (standardized by C++11)
 238 
 239 // Build a 64bit integer constant
 240 #define CONST64(x)  (x ## LL)
 241 #define UCONST64(x) (x ## ULL)
 242 
 243 const jlong min_jlong = CONST64(0x8000000000000000);
 244 const jlong max_jlong = CONST64(0x7fffffffffffffff);
 245 
 246 const size_t K                  = 1024;
 247 const size_t M                  = K*K;
 248 const size_t G                  = M*K;
 249 const size_t HWperKB            = K / sizeof(HeapWord);
 250 
 251 // Constants for converting from a base unit to milli-base units.  For
 252 // example from seconds to milliseconds and microseconds
 253 
 254 const int MILLIUNITS    = 1000;         // milli units per base unit
 255 const int MICROUNITS    = 1000000;      // micro units per base unit
 256 const int NANOUNITS     = 1000000000;   // nano units per base unit
 257 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS;
 258 
 259 const jlong NANOSECS_PER_SEC      = CONST64(1000000000);
 260 const jint  NANOSECS_PER_MILLISEC = 1000000;
 261 
 262 
 263 // Unit conversion functions
 264 // The caller is responsible for considering overlow.
 265 
 266 inline int64_t nanos_to_millis(int64_t nanos) {
 267   return nanos / NANOUNITS_PER_MILLIUNIT;
 268 }
 269 inline int64_t millis_to_nanos(int64_t millis) {
 270   return millis * NANOUNITS_PER_MILLIUNIT;
 271 }
 272 
 273 // Proper units routines try to maintain at least three significant digits.
 274 // In worst case, it would print five significant digits with lower prefix.
 275 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow,
 276 // and therefore we need to be careful.
 277 
 278 inline const char* proper_unit_for_byte_size(size_t s) {
 279 #ifdef _LP64
 280   if (s >= 100*G) {
 281     return "G";
 282   }
 283 #endif
 284   if (s >= 100*M) {
 285     return "M";
 286   } else if (s >= 100*K) {
 287     return "K";
 288   } else {
 289     return "B";
 290   }
 291 }
 292 
 293 template <class T>
 294 inline T byte_size_in_proper_unit(T s) {
 295 #ifdef _LP64
 296   if (s >= 100*G) {
 297     return (T)(s/G);
 298   }
 299 #endif
 300   if (s >= 100*M) {
 301     return (T)(s/M);
 302   } else if (s >= 100*K) {
 303     return (T)(s/K);
 304   } else {
 305     return s;
 306   }
 307 }
 308 
 309 inline const char* exact_unit_for_byte_size(size_t s) {
 310 #ifdef _LP64
 311   if (s >= G && (s % G) == 0) {
 312     return "G";
 313   }
 314 #endif
 315   if (s >= M && (s % M) == 0) {
 316     return "M";
 317   }
 318   if (s >= K && (s % K) == 0) {
 319     return "K";
 320   }
 321   return "B";
 322 }
 323 
 324 inline size_t byte_size_in_exact_unit(size_t s) {
 325 #ifdef _LP64
 326   if (s >= G && (s % G) == 0) {
 327     return s / G;
 328   }
 329 #endif
 330   if (s >= M && (s % M) == 0) {
 331     return s / M;
 332   }
 333   if (s >= K && (s % K) == 0) {
 334     return s / K;
 335   }
 336   return s;
 337 }
 338 
 339 // Memory size transition formatting.
 340 
 341 #define HEAP_CHANGE_FORMAT "%s: " SIZE_FORMAT "K(" SIZE_FORMAT "K)->" SIZE_FORMAT "K(" SIZE_FORMAT "K)"
 342 
 343 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \
 344   (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K
 345 
 346 //----------------------------------------------------------------------------------------------------
 347 // VM type definitions
 348 
 349 // intx and uintx are the 'extended' int and 'extended' unsigned int types;
 350 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.
 351 
 352 typedef intptr_t  intx;
 353 typedef uintptr_t uintx;
 354 
 355 const intx  min_intx  = (intx)1 << (sizeof(intx)*BitsPerByte-1);
 356 const intx  max_intx  = (uintx)min_intx - 1;
 357 const uintx max_uintx = (uintx)-1;
 358 
 359 // Table of values:
 360 //      sizeof intx         4               8
 361 // min_intx             0x80000000      0x8000000000000000
 362 // max_intx             0x7FFFFFFF      0x7FFFFFFFFFFFFFFF
 363 // max_uintx            0xFFFFFFFF      0xFFFFFFFFFFFFFFFF
 364 
 365 typedef unsigned int uint;   NEEDS_CLEANUP
 366 
 367 
 368 //----------------------------------------------------------------------------------------------------
 369 // Java type definitions
 370 
 371 // All kinds of 'plain' byte addresses
 372 typedef   signed char s_char;
 373 typedef unsigned char u_char;
 374 typedef u_char*       address;
 375 typedef uintptr_t     address_word; // unsigned integer which will hold a pointer
 376                                     // except for some implementations of a C++
 377                                     // linkage pointer to function. Should never
 378                                     // need one of those to be placed in this
 379                                     // type anyway.
 380 
 381 //  Utility functions to "portably" (?) bit twiddle pointers
 382 //  Where portable means keep ANSI C++ compilers quiet
 383 
 384 inline address       set_address_bits(address x, int m)       { return address(intptr_t(x) | m); }
 385 inline address       clear_address_bits(address x, int m)     { return address(intptr_t(x) & ~m); }
 386 
 387 //  Utility functions to "portably" make cast to/from function pointers.
 388 
 389 inline address_word  mask_address_bits(address x, int m)      { return address_word(x) & m; }
 390 inline address_word  castable_address(address x)              { return address_word(x) ; }
 391 inline address_word  castable_address(void* x)                { return address_word(x) ; }
 392 
 393 // Pointer subtraction.
 394 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have
 395 // the range we might need to find differences from one end of the heap
 396 // to the other.
 397 // A typical use might be:
 398 //     if (pointer_delta(end(), top()) >= size) {
 399 //       // enough room for an object of size
 400 //       ...
 401 // and then additions like
 402 //       ... top() + size ...
 403 // are safe because we know that top() is at least size below end().
 404 inline size_t pointer_delta(const volatile void* left,
 405                             const volatile void* right,
 406                             size_t element_size) {
 407   return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;
 408 }
 409 
 410 // A version specialized for HeapWord*'s.
 411 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {
 412   return pointer_delta(left, right, sizeof(HeapWord));
 413 }
 414 // A version specialized for MetaWord*'s.
 415 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) {
 416   return pointer_delta(left, right, sizeof(MetaWord));
 417 }
 418 
 419 //
 420 // ANSI C++ does not allow casting from one pointer type to a function pointer
 421 // directly without at best a warning. This macro accomplishes it silently
 422 // In every case that is present at this point the value be cast is a pointer
 423 // to a C linkage function. In some case the type used for the cast reflects
 424 // that linkage and a picky compiler would not complain. In other cases because
 425 // there is no convenient place to place a typedef with extern C linkage (i.e
 426 // a platform dependent header file) it doesn't. At this point no compiler seems
 427 // picky enough to catch these instances (which are few). It is possible that
 428 // using templates could fix these for all cases. This use of templates is likely
 429 // so far from the middle of the road that it is likely to be problematic in
 430 // many C++ compilers.
 431 //
 432 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value))
 433 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((address_word)(func_ptr)))
 434 
 435 // Unsigned byte types for os and stream.hpp
 436 
 437 // Unsigned one, two, four and eigth byte quantities used for describing
 438 // the .class file format. See JVM book chapter 4.
 439 
 440 typedef jubyte  u1;
 441 typedef jushort u2;
 442 typedef juint   u4;
 443 typedef julong  u8;
 444 
 445 const jubyte  max_jubyte  = (jubyte)-1;  // 0xFF       largest jubyte
 446 const jushort max_jushort = (jushort)-1; // 0xFFFF     largest jushort
 447 const juint   max_juint   = (juint)-1;   // 0xFFFFFFFF largest juint
 448 const julong  max_julong  = (julong)-1;  // 0xFF....FF largest julong
 449 
 450 typedef jbyte  s1;
 451 typedef jshort s2;
 452 typedef jint   s4;
 453 typedef jlong  s8;
 454 
 455 const jbyte min_jbyte = -(1 << 7);       // smallest jbyte
 456 const jbyte max_jbyte = (1 << 7) - 1;    // largest jbyte
 457 const jshort min_jshort = -(1 << 15);    // smallest jshort
 458 const jshort max_jshort = (1 << 15) - 1; // largest jshort
 459 
 460 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
 461 const jint max_jint = (juint)min_jint - 1;                     // 0x7FFFFFFF == largest jint
 462 
 463 //----------------------------------------------------------------------------------------------------
 464 // JVM spec restrictions
 465 
 466 const int max_method_code_size = 64*K - 1;  // JVM spec, 2nd ed. section 4.8.1 (p.134)
 467 
 468 //----------------------------------------------------------------------------------------------------
 469 // Object alignment, in units of HeapWords.
 470 //
 471 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and
 472 // reference fields can be naturally aligned.
 473 
 474 extern int MinObjAlignment;
 475 extern int MinObjAlignmentInBytes;
 476 extern int MinObjAlignmentInBytesMask;
 477 
 478 extern int LogMinObjAlignment;
 479 extern int LogMinObjAlignmentInBytes;
 480 
 481 const int LogKlassAlignmentInBytes = 3;
 482 const int LogKlassAlignment        = LogKlassAlignmentInBytes - LogHeapWordSize;
 483 const int KlassAlignmentInBytes    = 1 << LogKlassAlignmentInBytes;
 484 const int KlassAlignment           = KlassAlignmentInBytes / HeapWordSize;
 485 
 486 // Maximal size of heap where unscaled compression can be used. Also upper bound
 487 // for heap placement: 4GB.
 488 const  uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
 489 // Maximal size of heap where compressed oops can be used. Also upper bound for heap
 490 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes.
 491 extern uint64_t OopEncodingHeapMax;
 492 
 493 // Maximal size of compressed class space. Above this limit compression is not possible.
 494 // Also upper bound for placement of zero based class space. (Class space is further limited
 495 // to be < 3G, see arguments.cpp.)
 496 const  uint64_t KlassEncodingMetaspaceMax = (uint64_t(max_juint) + 1) << LogKlassAlignmentInBytes;
 497 
 498 // Machine dependent stuff
 499 
 500 // The maximum size of the code cache.  Can be overridden by targets.
 501 #define CODE_CACHE_SIZE_LIMIT (2*G)
 502 // Allow targets to reduce the default size of the code cache.
 503 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT
 504 
 505 #include CPU_HEADER(globalDefinitions)
 506 
 507 // To assure the IRIW property on processors that are not multiple copy
 508 // atomic, sync instructions must be issued between volatile reads to
 509 // assure their ordering, instead of after volatile stores.
 510 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models"
 511 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge)
 512 #ifdef CPU_MULTI_COPY_ATOMIC
 513 // Not needed.
 514 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false;
 515 #else
 516 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment.
 517 // Final decision is subject to JEP 188: Java Memory Model Update.
 518 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false);
 519 #endif
 520 
 521 // The expected size in bytes of a cache line, used to pad data structures.
 522 #ifndef DEFAULT_CACHE_LINE_SIZE
 523   #define DEFAULT_CACHE_LINE_SIZE 64
 524 #endif
 525 
 526 
 527 //----------------------------------------------------------------------------------------------------
 528 // Utility macros for compilers
 529 // used to silence compiler warnings
 530 
 531 #define Unused_Variable(var) var
 532 
 533 
 534 //----------------------------------------------------------------------------------------------------
 535 // Miscellaneous
 536 
 537 // 6302670 Eliminate Hotspot __fabsf dependency
 538 // All fabs() callers should call this function instead, which will implicitly
 539 // convert the operand to double, avoiding a dependency on __fabsf which
 540 // doesn't exist in early versions of Solaris 8.
 541 inline double fabsd(double value) {
 542   return fabs(value);
 543 }
 544 
 545 // Returns numerator/denominator as percentage value from 0 to 100. If denominator
 546 // is zero, return 0.0.
 547 template<typename T>
 548 inline double percent_of(T numerator, T denominator) {
 549   return denominator != 0 ? (double)numerator / denominator * 100.0 : 0.0;
 550 }
 551 
 552 //----------------------------------------------------------------------------------------------------
 553 // Special casts
 554 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern
 555 typedef union {
 556   jfloat f;
 557   jint i;
 558 } FloatIntConv;
 559 
 560 typedef union {
 561   jdouble d;
 562   jlong l;
 563   julong ul;
 564 } DoubleLongConv;
 565 
 566 inline jint    jint_cast    (jfloat  x)  { return ((FloatIntConv*)&x)->i; }
 567 inline jfloat  jfloat_cast  (jint    x)  { return ((FloatIntConv*)&x)->f; }
 568 
 569 inline jlong   jlong_cast   (jdouble x)  { return ((DoubleLongConv*)&x)->l;  }
 570 inline julong  julong_cast  (jdouble x)  { return ((DoubleLongConv*)&x)->ul; }
 571 inline jdouble jdouble_cast (jlong   x)  { return ((DoubleLongConv*)&x)->d;  }
 572 
 573 inline jint low (jlong value)                    { return jint(value); }
 574 inline jint high(jlong value)                    { return jint(value >> 32); }
 575 
 576 // the fancy casts are a hopefully portable way
 577 // to do unsigned 32 to 64 bit type conversion
 578 inline void set_low (jlong* value, jint low )    { *value &= (jlong)0xffffffff << 32;
 579                                                    *value |= (jlong)(julong)(juint)low; }
 580 
 581 inline void set_high(jlong* value, jint high)    { *value &= (jlong)(julong)(juint)0xffffffff;
 582                                                    *value |= (jlong)high       << 32; }
 583 
 584 inline jlong jlong_from(jint h, jint l) {
 585   jlong result = 0; // initialization to avoid warning
 586   set_high(&result, h);
 587   set_low(&result,  l);
 588   return result;
 589 }
 590 
 591 union jlong_accessor {
 592   jint  words[2];
 593   jlong long_value;
 594 };
 595 
 596 void basic_types_init(); // cannot define here; uses assert
 597 
 598 
 599 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 600 enum BasicType {
 601 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS.
 602   T_BOOLEAN     = JVM_T_BOOLEAN,
 603   T_CHAR        = JVM_T_CHAR,
 604   T_FLOAT       = JVM_T_FLOAT,
 605   T_DOUBLE      = JVM_T_DOUBLE,
 606   T_BYTE        = JVM_T_BYTE,
 607   T_SHORT       = JVM_T_SHORT,
 608   T_INT         = JVM_T_INT,
 609   T_LONG        = JVM_T_LONG,
 610   // The remaining values are not part of any standard.
 611   // T_OBJECT and T_VOID denote two more semantic choices
 612   // for method return values.
 613   // T_OBJECT and T_ARRAY describe signature syntax.
 614   // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe
 615   // internal references within the JVM as if they were Java
 616   // types in their own right.
 617   T_OBJECT      = 12,
 618   T_ARRAY       = 13,
 619   T_VOID        = 14,
 620   T_ADDRESS     = 15,
 621   T_NARROWOOP   = 16,
 622   T_METADATA    = 17,
 623   T_NARROWKLASS = 18,
 624   T_CONFLICT    = 19, // for stack value type with conflicting contents
 625   T_ILLEGAL     = 99
 626 };
 627 
 628 #define SIGNATURE_TYPES_DO(F, N)                \
 629     F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N)      \
 630     F(JVM_SIGNATURE_CHAR,    T_CHAR,    N)      \
 631     F(JVM_SIGNATURE_FLOAT,   T_FLOAT,   N)      \
 632     F(JVM_SIGNATURE_DOUBLE,  T_DOUBLE,  N)      \
 633     F(JVM_SIGNATURE_BYTE,    T_BYTE,    N)      \
 634     F(JVM_SIGNATURE_SHORT,   T_SHORT,   N)      \
 635     F(JVM_SIGNATURE_INT,     T_INT,     N)      \
 636     F(JVM_SIGNATURE_LONG,    T_LONG,    N)      \
 637     F(JVM_SIGNATURE_CLASS,   T_OBJECT,  N)      \
 638     F(JVM_SIGNATURE_ARRAY,   T_ARRAY,   N)      \
 639     F(JVM_SIGNATURE_VOID,    T_VOID,    N)      \
 640     /*end*/
 641 
 642 inline bool is_java_type(BasicType t) {
 643   return T_BOOLEAN <= t && t <= T_VOID;
 644 }
 645 
 646 inline bool is_java_primitive(BasicType t) {
 647   return T_BOOLEAN <= t && t <= T_LONG;
 648 }
 649 
 650 inline bool is_subword_type(BasicType t) {
 651   // these guys are processed exactly like T_INT in calling sequences:
 652   return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);
 653 }
 654 
 655 inline bool is_signed_subword_type(BasicType t) {
 656   return (t == T_BYTE || t == T_SHORT);
 657 }
 658 
 659 inline bool is_double_word_type(BasicType t) {
 660   return (t == T_DOUBLE || t == T_LONG);
 661 }
 662 
 663 inline bool is_reference_type(BasicType t) {
 664   return (t == T_OBJECT || t == T_ARRAY);
 665 }
 666 
 667 extern char type2char_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 668 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }
 669 extern int type2size[T_CONFLICT+1];         // Map BasicType to result stack elements
 670 extern const char* type2name_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 671 inline const char* type2name(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2name_tab[t] : NULL; }
 672 extern BasicType name2type(const char* name);
 673 
 674 // Auxiliary math routines
 675 // least common multiple
 676 extern size_t lcm(size_t a, size_t b);
 677 
 678 
 679 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 680 enum BasicTypeSize {
 681   T_BOOLEAN_size     = 1,
 682   T_CHAR_size        = 1,
 683   T_FLOAT_size       = 1,
 684   T_DOUBLE_size      = 2,
 685   T_BYTE_size        = 1,
 686   T_SHORT_size       = 1,
 687   T_INT_size         = 1,
 688   T_LONG_size        = 2,
 689   T_OBJECT_size      = 1,
 690   T_ARRAY_size       = 1,
 691   T_NARROWOOP_size   = 1,
 692   T_NARROWKLASS_size = 1,
 693   T_VOID_size        = 0
 694 };
 695 
 696 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc.
 697 inline int parameter_type_word_count(BasicType t) {
 698   if (is_double_word_type(t))  return 2;
 699   assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please");
 700   assert(type2size[t] == 1, "must be");
 701   return 1;
 702 }
 703 
 704 // maps a BasicType to its instance field storage type:
 705 // all sub-word integral types are widened to T_INT
 706 extern BasicType type2field[T_CONFLICT+1];
 707 extern BasicType type2wfield[T_CONFLICT+1];
 708 
 709 
 710 // size in bytes
 711 enum ArrayElementSize {
 712   T_BOOLEAN_aelem_bytes     = 1,
 713   T_CHAR_aelem_bytes        = 2,
 714   T_FLOAT_aelem_bytes       = 4,
 715   T_DOUBLE_aelem_bytes      = 8,
 716   T_BYTE_aelem_bytes        = 1,
 717   T_SHORT_aelem_bytes       = 2,
 718   T_INT_aelem_bytes         = 4,
 719   T_LONG_aelem_bytes        = 8,
 720 #ifdef _LP64
 721   T_OBJECT_aelem_bytes      = 8,
 722   T_ARRAY_aelem_bytes       = 8,
 723 #else
 724   T_OBJECT_aelem_bytes      = 4,
 725   T_ARRAY_aelem_bytes       = 4,
 726 #endif
 727   T_NARROWOOP_aelem_bytes   = 4,
 728   T_NARROWKLASS_aelem_bytes = 4,
 729   T_VOID_aelem_bytes        = 0
 730 };
 731 
 732 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element
 733 #ifdef ASSERT
 734 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts
 735 #else
 736 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; }
 737 #endif
 738 
 739 
 740 // JavaValue serves as a container for arbitrary Java values.
 741 
 742 class JavaValue {
 743 
 744  public:
 745   typedef union JavaCallValue {
 746     jfloat   f;
 747     jdouble  d;
 748     jint     i;
 749     jlong    l;
 750     jobject  h;
 751   } JavaCallValue;
 752 
 753  private:
 754   BasicType _type;
 755   JavaCallValue _value;
 756 
 757  public:
 758   JavaValue(BasicType t = T_ILLEGAL) { _type = t; }
 759 
 760   JavaValue(jfloat value) {
 761     _type    = T_FLOAT;
 762     _value.f = value;
 763   }
 764 
 765   JavaValue(jdouble value) {
 766     _type    = T_DOUBLE;
 767     _value.d = value;
 768   }
 769 
 770  jfloat get_jfloat() const { return _value.f; }
 771  jdouble get_jdouble() const { return _value.d; }
 772  jint get_jint() const { return _value.i; }
 773  jlong get_jlong() const { return _value.l; }
 774  jobject get_jobject() const { return _value.h; }
 775  JavaCallValue* get_value_addr() { return &_value; }
 776  BasicType get_type() const { return _type; }
 777 
 778  void set_jfloat(jfloat f) { _value.f = f;}
 779  void set_jdouble(jdouble d) { _value.d = d;}
 780  void set_jint(jint i) { _value.i = i;}
 781  void set_jlong(jlong l) { _value.l = l;}
 782  void set_jobject(jobject h) { _value.h = h;}
 783  void set_type(BasicType t) { _type = t; }
 784 
 785  jboolean get_jboolean() const { return (jboolean) (_value.i);}
 786  jbyte get_jbyte() const { return (jbyte) (_value.i);}
 787  jchar get_jchar() const { return (jchar) (_value.i);}
 788  jshort get_jshort() const { return (jshort) (_value.i);}
 789 
 790 };
 791 
 792 
 793 #define STACK_BIAS      0
 794 // V9 Sparc CPU's running in 64 Bit mode use a stack bias of 7ff
 795 // in order to extend the reach of the stack pointer.
 796 #if defined(SPARC) && defined(_LP64)
 797 #undef STACK_BIAS
 798 #define STACK_BIAS      0x7ff
 799 #endif
 800 
 801 
 802 // TosState describes the top-of-stack state before and after the execution of
 803 // a bytecode or method. The top-of-stack value may be cached in one or more CPU
 804 // registers. The TosState corresponds to the 'machine representation' of this cached
 805 // value. There's 4 states corresponding to the JAVA types int, long, float & double
 806 // as well as a 5th state in case the top-of-stack value is actually on the top
 807 // of stack (in memory) and thus not cached. The atos state corresponds to the itos
 808 // state when it comes to machine representation but is used separately for (oop)
 809 // type specific operations (e.g. verification code).
 810 
 811 enum TosState {         // describes the tos cache contents
 812   btos = 0,             // byte, bool tos cached
 813   ztos = 1,             // byte, bool tos cached
 814   ctos = 2,             // char tos cached
 815   stos = 3,             // short tos cached
 816   itos = 4,             // int tos cached
 817   ltos = 5,             // long tos cached
 818   ftos = 6,             // float tos cached
 819   dtos = 7,             // double tos cached
 820   atos = 8,             // object cached
 821   vtos = 9,             // tos not cached
 822   number_of_states,
 823   ilgl                  // illegal state: should not occur
 824 };
 825 
 826 
 827 inline TosState as_TosState(BasicType type) {
 828   switch (type) {
 829     case T_BYTE   : return btos;
 830     case T_BOOLEAN: return ztos;
 831     case T_CHAR   : return ctos;
 832     case T_SHORT  : return stos;
 833     case T_INT    : return itos;
 834     case T_LONG   : return ltos;
 835     case T_FLOAT  : return ftos;
 836     case T_DOUBLE : return dtos;
 837     case T_VOID   : return vtos;
 838     case T_ARRAY  : // fall through
 839     case T_OBJECT : return atos;
 840     default       : return ilgl;
 841   }
 842 }
 843 
 844 inline BasicType as_BasicType(TosState state) {
 845   switch (state) {
 846     case btos : return T_BYTE;
 847     case ztos : return T_BOOLEAN;
 848     case ctos : return T_CHAR;
 849     case stos : return T_SHORT;
 850     case itos : return T_INT;
 851     case ltos : return T_LONG;
 852     case ftos : return T_FLOAT;
 853     case dtos : return T_DOUBLE;
 854     case atos : return T_OBJECT;
 855     case vtos : return T_VOID;
 856     default   : return T_ILLEGAL;
 857   }
 858 }
 859 
 860 
 861 // Helper function to convert BasicType info into TosState
 862 // Note: Cannot define here as it uses global constant at the time being.
 863 TosState as_TosState(BasicType type);
 864 
 865 
 866 // JavaThreadState keeps track of which part of the code a thread is executing in. This
 867 // information is needed by the safepoint code.
 868 //
 869 // There are 4 essential states:
 870 //
 871 //  _thread_new         : Just started, but not executed init. code yet (most likely still in OS init code)
 872 //  _thread_in_native   : In native code. This is a safepoint region, since all oops will be in jobject handles
 873 //  _thread_in_vm       : Executing in the vm
 874 //  _thread_in_Java     : Executing either interpreted or compiled Java code (or could be in a stub)
 875 //
 876 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in
 877 // a transition from one state to another. These extra states makes it possible for the safepoint code to
 878 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.
 879 //
 880 // Given a state, the xxxx_trans state can always be found by adding 1.
 881 //
 882 enum JavaThreadState {
 883   _thread_uninitialized     =  0, // should never happen (missing initialization)
 884   _thread_new               =  2, // just starting up, i.e., in process of being initialized
 885   _thread_new_trans         =  3, // corresponding transition state (not used, included for completness)
 886   _thread_in_native         =  4, // running in native code
 887   _thread_in_native_trans   =  5, // corresponding transition state
 888   _thread_in_vm             =  6, // running in VM
 889   _thread_in_vm_trans       =  7, // corresponding transition state
 890   _thread_in_Java           =  8, // running in Java or in stub code
 891   _thread_in_Java_trans     =  9, // corresponding transition state (not used, included for completness)
 892   _thread_blocked           = 10, // blocked in vm
 893   _thread_blocked_trans     = 11, // corresponding transition state
 894   _thread_max_state         = 12  // maximum thread state+1 - used for statistics allocation
 895 };
 896 
 897 //----------------------------------------------------------------------------------------------------
 898 // Special constants for debugging
 899 
 900 const jint     badInt           = -3;                       // generic "bad int" value
 901 const intptr_t badAddressVal    = -2;                       // generic "bad address" value
 902 const intptr_t badOopVal        = -1;                       // generic "bad oop" value
 903 const intptr_t badHeapOopVal    = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC
 904 const int      badStackSegVal   = 0xCA;                     // value used to zap stack segments
 905 const int      badHandleValue   = 0xBC;                     // value used to zap vm handle area
 906 const int      badResourceValue = 0xAB;                     // value used to zap resource area
 907 const int      freeBlockPad     = 0xBA;                     // value used to pad freed blocks.
 908 const int      uninitBlockPad   = 0xF1;                     // value used to zap newly malloc'd blocks.
 909 const juint    uninitMetaWordVal= 0xf7f7f7f7;               // value used to zap newly allocated metachunk
 910 const juint    badHeapWordVal   = 0xBAADBABE;               // value used to zap heap after GC
 911 const juint    badMetaWordVal   = 0xBAADFADE;               // value used to zap metadata heap after GC
 912 const int      badCodeHeapNewVal= 0xCC;                     // value used to zap Code heap at allocation
 913 const int      badCodeHeapFreeVal = 0xDD;                   // value used to zap Code heap at deallocation
 914 
 915 
 916 // (These must be implemented as #defines because C++ compilers are
 917 // not obligated to inline non-integral constants!)
 918 #define       badAddress        ((address)::badAddressVal)
 919 #define       badOop            (cast_to_oop(::badOopVal))
 920 #define       badHeapWord       (::badHeapWordVal)
 921 
 922 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)
 923 #define TASKQUEUE_SIZE (NOT_LP64(1<<14) LP64_ONLY(1<<17))
 924 
 925 //----------------------------------------------------------------------------------------------------
 926 // Utility functions for bitfield manipulations
 927 
 928 const intptr_t AllBits    = ~0; // all bits set in a word
 929 const intptr_t NoBits     =  0; // no bits set in a word
 930 const jlong    NoLongBits =  0; // no bits set in a long
 931 const intptr_t OneBit     =  1; // only right_most bit set in a word
 932 
 933 // get a word with the n.th or the right-most or left-most n bits set
 934 // (note: #define used only so that they can be used in enum constant definitions)
 935 #define nth_bit(n)        (((n) >= BitsPerWord) ? 0 : (OneBit << (n)))
 936 #define right_n_bits(n)   (nth_bit(n) - 1)
 937 #define left_n_bits(n)    (right_n_bits(n) << (((n) >= BitsPerWord) ? 0 : (BitsPerWord - (n))))
 938 
 939 // bit-operations using a mask m
 940 inline void   set_bits    (intptr_t& x, intptr_t m) { x |= m; }
 941 inline void clear_bits    (intptr_t& x, intptr_t m) { x &= ~m; }
 942 inline intptr_t mask_bits      (intptr_t  x, intptr_t m) { return x & m; }
 943 inline jlong    mask_long_bits (jlong     x, jlong    m) { return x & m; }
 944 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }
 945 
 946 // bit-operations using the n.th bit
 947 inline void    set_nth_bit(intptr_t& x, int n) { set_bits  (x, nth_bit(n)); }
 948 inline void  clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }
 949 inline bool is_set_nth_bit(intptr_t  x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }
 950 
 951 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)
 952 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {
 953   return mask_bits(x >> start_bit_no, right_n_bits(field_length));
 954 }
 955 
 956 
 957 //----------------------------------------------------------------------------------------------------
 958 // Utility functions for integers
 959 
 960 // Avoid use of global min/max macros which may cause unwanted double
 961 // evaluation of arguments.
 962 #ifdef max
 963 #undef max
 964 #endif
 965 
 966 #ifdef min
 967 #undef min
 968 #endif
 969 
 970 // It is necessary to use templates here. Having normal overloaded
 971 // functions does not work because it is necessary to provide both 32-
 972 // and 64-bit overloaded functions, which does not work, and having
 973 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)
 974 // will be even more error-prone than macros.
 975 template<class T> inline T MAX2(T a, T b)           { return (a > b) ? a : b; }
 976 template<class T> inline T MIN2(T a, T b)           { return (a < b) ? a : b; }
 977 template<class T> inline T MAX3(T a, T b, T c)      { return MAX2(MAX2(a, b), c); }
 978 template<class T> inline T MIN3(T a, T b, T c)      { return MIN2(MIN2(a, b), c); }
 979 template<class T> inline T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }
 980 template<class T> inline T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }
 981 
 982 template<class T> inline T ABS(T x)                 { return (x > 0) ? x : -x; }
 983 
 984 // Return the given value clamped to the range [min ... max]
 985 template<typename T>
 986 inline T clamp(T value, T min, T max) {
 987   assert(min <= max, "must be");
 988   return MIN2(MAX2(value, min), max);
 989 }
 990 
 991 // Returns largest i such that 2^i <= x.
 992 // If x == 0, the function returns -1.
 993 inline int log2_intptr(uintptr_t x) {
 994   int i = -1;
 995   uintptr_t p = 1;
 996   while (p != 0 && p <= x) {
 997     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
 998     i++; p *= 2;
 999   }
1000   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))
1001   // If p = 0, overflow has occurred and i = 31 or i = 63 (depending on the machine word size).
1002   return i;
1003 }
1004 
1005 //* largest i such that 2^i <= x
1006 inline int log2_long(julong x) {
1007   int i = -1;
1008   julong p =  1;
1009   while (p != 0 && p <= x) {
1010     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
1011     i++; p *= 2;
1012   }
1013   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))
1014   // (if p = 0 then overflow occurred and i = 63)
1015   return i;
1016 }
1017 
1018 // If x < 0, the function returns 31 on a 32-bit machine and 63 on a 64-bit machine.
1019 inline int log2_intptr(intptr_t x) {
1020   return log2_intptr((uintptr_t)x);
1021 }
1022 
1023 inline int log2_int(int x) {
1024   STATIC_ASSERT(sizeof(int) <= sizeof(uintptr_t));
1025   return log2_intptr((uintptr_t)(unsigned int)x);
1026 }
1027 
1028 inline int log2_jint(jint x) {
1029   STATIC_ASSERT(sizeof(jint) <= sizeof(uintptr_t));
1030   return log2_intptr((uintptr_t)(juint)x);
1031 }
1032 
1033 inline int log2_uint(uint x) {
1034   STATIC_ASSERT(sizeof(uint) <= sizeof(uintptr_t));
1035   return log2_intptr((uintptr_t)x);
1036 }
1037 
1038 //  A negative value of 'x' will return '63'
1039 inline int log2_jlong(jlong x) {
1040   STATIC_ASSERT(sizeof(jlong) <= sizeof(julong));
1041   return log2_long((julong)x);
1042 }
1043 
1044 inline bool is_odd (intx x) { return x & 1;      }
1045 inline bool is_even(intx x) { return !is_odd(x); }
1046 
1047 // abs methods which cannot overflow and so are well-defined across
1048 // the entire domain of integer types.
1049 static inline unsigned int uabs(unsigned int n) {
1050   union {
1051     unsigned int result;
1052     int value;
1053   };
1054   result = n;
1055   if (value < 0) result = 0-result;
1056   return result;
1057 }
1058 static inline julong uabs(julong n) {
1059   union {
1060     julong result;
1061     jlong value;
1062   };
1063   result = n;
1064   if (value < 0) result = 0-result;
1065   return result;
1066 }
1067 static inline julong uabs(jlong n) { return uabs((julong)n); }
1068 static inline unsigned int uabs(int n) { return uabs((unsigned int)n); }
1069 
1070 // "to" should be greater than "from."
1071 inline intx byte_size(void* from, void* to) {
1072   return (address)to - (address)from;
1073 }
1074 
1075 
1076 // Pack and extract shorts to/from ints:
1077 
1078 inline int extract_low_short_from_int(jint x) {
1079   return x & 0xffff;
1080 }
1081 
1082 inline int extract_high_short_from_int(jint x) {
1083   return (x >> 16) & 0xffff;
1084 }
1085 
1086 inline int build_int_from_shorts( jushort low, jushort high ) {
1087   return ((int)((unsigned int)high << 16) | (unsigned int)low);
1088 }
1089 
1090 // Convert pointer to intptr_t, for use in printing pointers.
1091 inline intptr_t p2i(const void * p) {
1092   return (intptr_t) p;
1093 }
1094 
1095 // swap a & b
1096 template<class T> static void swap(T& a, T& b) {
1097   T tmp = a;
1098   a = b;
1099   b = tmp;
1100 }
1101 
1102 #define ARRAY_SIZE(array) (sizeof(array)/sizeof((array)[0]))
1103 
1104 //----------------------------------------------------------------------------------------------------
1105 // Sum and product which can never overflow: they wrap, just like the
1106 // Java operations.  Note that we don't intend these to be used for
1107 // general-purpose arithmetic: their purpose is to emulate Java
1108 // operations.
1109 
1110 // The goal of this code to avoid undefined or implementation-defined
1111 // behavior.  The use of an lvalue to reference cast is explicitly
1112 // permitted by Lvalues and rvalues [basic.lval].  [Section 3.10 Para
1113 // 15 in C++03]
1114 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE)  \
1115 inline TYPE NAME (TYPE in1, TYPE in2) {                 \
1116   UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \
1117   ures OP ## = static_cast<UNSIGNED_TYPE>(in2);         \
1118   return reinterpret_cast<TYPE&>(ures);                 \
1119 }
1120 
1121 JAVA_INTEGER_OP(+, java_add, jint, juint)
1122 JAVA_INTEGER_OP(-, java_subtract, jint, juint)
1123 JAVA_INTEGER_OP(*, java_multiply, jint, juint)
1124 JAVA_INTEGER_OP(+, java_add, jlong, julong)
1125 JAVA_INTEGER_OP(-, java_subtract, jlong, julong)
1126 JAVA_INTEGER_OP(*, java_multiply, jlong, julong)
1127 
1128 #undef JAVA_INTEGER_OP
1129 
1130 // Provide integer shift operations with Java semantics.  No overflow
1131 // issues - left shifts simply discard shifted out bits.  No undefined
1132 // behavior for large or negative shift quantities; instead the actual
1133 // shift distance is the argument modulo the lhs value's size in bits.
1134 // No undefined or implementation defined behavior for shifting negative
1135 // values; left shift discards bits, right shift sign extends.  We use
1136 // the same safe conversion technique as above for java_add and friends.
1137 #define JAVA_INTEGER_SHIFT_OP(OP, NAME, TYPE, XTYPE)    \
1138 inline TYPE NAME (TYPE lhs, jint rhs) {                 \
1139   const uint rhs_mask = (sizeof(TYPE) * 8) - 1;         \
1140   STATIC_ASSERT(rhs_mask == 31 || rhs_mask == 63);      \
1141   XTYPE xres = static_cast<XTYPE>(lhs);                 \
1142   xres OP ## = (rhs & rhs_mask);                        \
1143   return reinterpret_cast<TYPE&>(xres);                 \
1144 }
1145 
1146 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jint, juint)
1147 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jlong, julong)
1148 // For signed shift right, assume C++ implementation >> sign extends.
1149 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jint, jint)
1150 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jlong, jlong)
1151 // For >>> use C++ unsigned >>.
1152 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jint, juint)
1153 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jlong, julong)
1154 
1155 #undef JAVA_INTEGER_SHIFT_OP
1156 
1157 //----------------------------------------------------------------------------------------------------
1158 // The goal of this code is to provide saturating operations for int/uint.
1159 // Checks overflow conditions and saturates the result to min_jint/max_jint.
1160 #define SATURATED_INTEGER_OP(OP, NAME, TYPE1, TYPE2) \
1161 inline int NAME (TYPE1 in1, TYPE2 in2) {             \
1162   jlong res = static_cast<jlong>(in1);               \
1163   res OP ## = static_cast<jlong>(in2);               \
1164   if (res > max_jint) {                              \
1165     res = max_jint;                                  \
1166   } else if (res < min_jint) {                       \
1167     res = min_jint;                                  \
1168   }                                                  \
1169   return static_cast<int>(res);                      \
1170 }
1171 
1172 SATURATED_INTEGER_OP(+, saturated_add, int, int)
1173 SATURATED_INTEGER_OP(+, saturated_add, int, uint)
1174 SATURATED_INTEGER_OP(+, saturated_add, uint, int)
1175 SATURATED_INTEGER_OP(+, saturated_add, uint, uint)
1176 
1177 #undef SATURATED_INTEGER_OP
1178 
1179 // Dereference vptr
1180 // All C++ compilers that we know of have the vtbl pointer in the first
1181 // word.  If there are exceptions, this function needs to be made compiler
1182 // specific.
1183 static inline void* dereference_vptr(const void* addr) {
1184   return *(void**)addr;
1185 }
1186 
1187 //----------------------------------------------------------------------------------------------------
1188 // String type aliases used by command line flag declarations and
1189 // processing utilities.
1190 
1191 typedef const char* ccstr;
1192 typedef const char* ccstrlist;   // represents string arguments which accumulate
1193 
1194 //----------------------------------------------------------------------------------------------------
1195 // Default hash/equals functions used by ResourceHashtable and KVHashtable
1196 
1197 template<typename K> unsigned primitive_hash(const K& k) {
1198   unsigned hash = (unsigned)((uintptr_t)k);
1199   return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs
1200 }
1201 
1202 template<typename K> bool primitive_equals(const K& k0, const K& k1) {
1203   return k0 == k1;
1204 }
1205 
1206 
1207 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP