1 /*
   2  * Copyright (c) 1997, 2021, 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_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 #include <cstddef>
  38 
  39 class oopDesc;
  40 
  41 // Defaults for macros that might be defined per compiler.
  42 #ifndef NOINLINE
  43 #define NOINLINE
  44 #endif
  45 #ifndef ALWAYSINLINE
  46 #define ALWAYSINLINE inline
  47 #endif
  48 #ifndef __HOT
  49 #define __HOT
  50 #endif
  51 #ifndef __COLD
  52 #define __COLD
  53 #endif
  54 
  55 #ifndef ATTRIBUTE_ALIGNED
  56 #define ATTRIBUTE_ALIGNED(x)
  57 #endif
  58 #ifndef LIKELY
  59 #define LIKELY(condition)   (condition)
  60 #endif
  61 #ifndef UNLIKELY
  62 #define UNLIKELY(condition) (condition)
  63 #endif
  64 
  65 #ifndef ATTRIBUTE_FLATTEN
  66 #define ATTRIBUTE_FLATTEN
  67 #endif
  68 
  69 // These are #defines to selectively turn on/off the Print(Opto)Assembly
  70 // capabilities. Choices should be led by a tradeoff between
  71 // code size and improved supportability.
  72 // if PRINT_ASSEMBLY then PRINT_ABSTRACT_ASSEMBLY must be true as well
  73 // to have a fallback in case hsdis is not available.
  74 #if defined(PRODUCT)
  75   #define SUPPORT_ABSTRACT_ASSEMBLY
  76   #define SUPPORT_ASSEMBLY
  77   #undef  SUPPORT_OPTO_ASSEMBLY      // Can't activate. In PRODUCT, many dump methods are missing.
  78   #undef  SUPPORT_DATA_STRUCTS       // Of limited use. In PRODUCT, many print methods are empty.
  79 #else
  80   #define SUPPORT_ABSTRACT_ASSEMBLY
  81   #define SUPPORT_ASSEMBLY
  82   #define SUPPORT_OPTO_ASSEMBLY
  83   #define SUPPORT_DATA_STRUCTS
  84 #endif
  85 #if defined(SUPPORT_ASSEMBLY) && !defined(SUPPORT_ABSTRACT_ASSEMBLY)
  86   #define SUPPORT_ABSTRACT_ASSEMBLY
  87 #endif
  88 
  89 // This file holds all globally used constants & types, class (forward)
  90 // declarations and a few frequently used utility functions.
  91 
  92 // Declare the named class to be noncopyable.  This macro must be followed by
  93 // a semi-colon.  The macro provides deleted declarations for the class's copy
  94 // constructor and assignment operator.  Because these operations are deleted,
  95 // they cannot be defined and potential callers will fail to compile.
  96 #define NONCOPYABLE(C) C(C const&) = delete; C& operator=(C const&) = delete /* next token must be ; */
  97 
  98 
  99 //----------------------------------------------------------------------------------------------------
 100 // Printf-style formatters for fixed- and variable-width types as pointers and
 101 // integers.  These are derived from the definitions in inttypes.h.  If the platform
 102 // doesn't provide appropriate definitions, they should be provided in
 103 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp)
 104 
 105 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false")
 106 
 107 // Format 32-bit quantities.
 108 #define INT32_FORMAT           "%" PRId32
 109 #define UINT32_FORMAT          "%" PRIu32
 110 #define INT32_FORMAT_W(width)  "%" #width PRId32
 111 #define UINT32_FORMAT_W(width) "%" #width PRIu32
 112 
 113 #define PTR32_FORMAT           "0x%08" PRIx32
 114 #define PTR32_FORMAT_W(width)  "0x%" #width PRIx32
 115 
 116 // Format 64-bit quantities.
 117 #define INT64_FORMAT           "%" PRId64
 118 #define UINT64_FORMAT          "%" PRIu64
 119 #define UINT64_FORMAT_X        "%" PRIx64
 120 #define INT64_FORMAT_W(width)  "%" #width PRId64
 121 #define UINT64_FORMAT_W(width) "%" #width PRIu64
 122 #define UINT64_FORMAT_X_W(width) "%" #width PRIx64
 123 
 124 #define PTR64_FORMAT           "0x%016" PRIx64
 125 
 126 // Format jlong, if necessary
 127 #ifndef JLONG_FORMAT
 128 #define JLONG_FORMAT           INT64_FORMAT
 129 #endif
 130 #ifndef JLONG_FORMAT_W
 131 #define JLONG_FORMAT_W(width)  INT64_FORMAT_W(width)
 132 #endif
 133 #ifndef JULONG_FORMAT
 134 #define JULONG_FORMAT          UINT64_FORMAT
 135 #endif
 136 #ifndef JULONG_FORMAT_X
 137 #define JULONG_FORMAT_X        UINT64_FORMAT_X
 138 #endif
 139 
 140 // Format pointers which change size between 32- and 64-bit.
 141 #ifdef  _LP64
 142 #define INTPTR_FORMAT "0x%016" PRIxPTR
 143 #define PTR_FORMAT    "0x%016" PRIxPTR
 144 #else   // !_LP64
 145 #define INTPTR_FORMAT "0x%08"  PRIxPTR
 146 #define PTR_FORMAT    "0x%08"  PRIxPTR
 147 #endif  // _LP64
 148 
 149 // Format pointers without leading zeros
 150 #define INTPTRNZ_FORMAT "0x%"  PRIxPTR
 151 
 152 #define INTPTR_FORMAT_W(width)   "%" #width PRIxPTR
 153 
 154 #define SSIZE_FORMAT             "%"   PRIdPTR
 155 #define SIZE_FORMAT              "%"   PRIuPTR
 156 #define SIZE_FORMAT_HEX          "0x%" PRIxPTR
 157 #define SSIZE_FORMAT_W(width)    "%"   #width PRIdPTR
 158 #define SIZE_FORMAT_W(width)     "%"   #width PRIuPTR
 159 #define SIZE_FORMAT_HEX_W(width) "0x%" #width PRIxPTR
 160 
 161 #define INTX_FORMAT           "%" PRIdPTR
 162 #define UINTX_FORMAT          "%" PRIuPTR
 163 #define INTX_FORMAT_W(width)  "%" #width PRIdPTR
 164 #define UINTX_FORMAT_W(width) "%" #width PRIuPTR
 165 
 166 // Convert pointer to intptr_t, for use in printing pointers.
 167 inline intptr_t p2i(const volatile void* p) {
 168   return (intptr_t) p;
 169 }
 170 
 171 //----------------------------------------------------------------------------------------------------
 172 // Constants
 173 
 174 const int LogBytesPerShort   = 1;
 175 const int LogBytesPerInt     = 2;
 176 #ifdef _LP64
 177 const int LogBytesPerWord    = 3;
 178 #else
 179 const int LogBytesPerWord    = 2;
 180 #endif
 181 const int LogBytesPerLong    = 3;
 182 
 183 const int BytesPerShort      = 1 << LogBytesPerShort;
 184 const int BytesPerInt        = 1 << LogBytesPerInt;
 185 const int BytesPerWord       = 1 << LogBytesPerWord;
 186 const int BytesPerLong       = 1 << LogBytesPerLong;
 187 
 188 const int LogBitsPerByte     = 3;
 189 const int LogBitsPerShort    = LogBitsPerByte + LogBytesPerShort;
 190 const int LogBitsPerInt      = LogBitsPerByte + LogBytesPerInt;
 191 const int LogBitsPerWord     = LogBitsPerByte + LogBytesPerWord;
 192 const int LogBitsPerLong     = LogBitsPerByte + LogBytesPerLong;
 193 
 194 const int BitsPerByte        = 1 << LogBitsPerByte;
 195 const int BitsPerShort       = 1 << LogBitsPerShort;
 196 const int BitsPerInt         = 1 << LogBitsPerInt;
 197 const int BitsPerWord        = 1 << LogBitsPerWord;
 198 const int BitsPerLong        = 1 << LogBitsPerLong;
 199 
 200 const int WordAlignmentMask  = (1 << LogBytesPerWord) - 1;
 201 const int LongAlignmentMask  = (1 << LogBytesPerLong) - 1;
 202 
 203 const int WordsPerLong       = 2;       // Number of stack entries for longs
 204 
 205 const int oopSize            = sizeof(char*); // Full-width oop
 206 extern int heapOopSize;                       // Oop within a java object
 207 const int wordSize           = sizeof(char*);
 208 const int longSize           = sizeof(jlong);
 209 const int jintSize           = sizeof(jint);
 210 const int size_tSize         = sizeof(size_t);
 211 
 212 const int BytesPerOop        = BytesPerWord;  // Full-width oop
 213 
 214 extern int LogBytesPerHeapOop;                // Oop within a java object
 215 extern int LogBitsPerHeapOop;
 216 extern int BytesPerHeapOop;
 217 extern int BitsPerHeapOop;
 218 
 219 const int BitsPerJavaInteger = 32;
 220 const int BitsPerJavaLong    = 64;
 221 const int BitsPerSize_t      = size_tSize * BitsPerByte;
 222 
 223 // Size of a char[] needed to represent a jint as a string in decimal.
 224 const int jintAsStringSize = 12;
 225 
 226 // An opaque type, so that HeapWord* can be a generic pointer into the heap.
 227 // We require that object sizes be measured in units of heap words (e.g.
 228 // pointer-sized values), so that given HeapWord* hw,
 229 //   hw += oop(hw)->foo();
 230 // works, where foo is a method (like size or scavenge) that returns the
 231 // object size.
 232 class HeapWordImpl;             // Opaque, never defined.
 233 typedef HeapWordImpl* HeapWord;
 234 
 235 // Analogous opaque struct for metadata allocated from metaspaces.
 236 class MetaWordImpl;             // Opaque, never defined.
 237 typedef MetaWordImpl* MetaWord;
 238 
 239 // HeapWordSize must be 2^LogHeapWordSize.
 240 const int HeapWordSize        = sizeof(HeapWord);
 241 #ifdef _LP64
 242 const int LogHeapWordSize     = 3;
 243 #else
 244 const int LogHeapWordSize     = 2;
 245 #endif
 246 const int HeapWordsPerLong    = BytesPerLong / HeapWordSize;
 247 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize;
 248 
 249 // The minimum number of native machine words necessary to contain "byte_size"
 250 // bytes.
 251 inline size_t heap_word_size(size_t byte_size) {
 252   return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize;
 253 }
 254 
 255 inline jfloat jfloat_cast(jint x);
 256 inline jdouble jdouble_cast(jlong x);
 257 
 258 //-------------------------------------------
 259 // Constant for jlong (standardized by C++11)
 260 
 261 // Build a 64bit integer constant
 262 #define CONST64(x)  (x ## LL)
 263 #define UCONST64(x) (x ## ULL)
 264 
 265 const jlong min_jlong = CONST64(0x8000000000000000);
 266 const jlong max_jlong = CONST64(0x7fffffffffffffff);
 267 
 268 //-------------------------------------------
 269 // Constant for jdouble
 270 const jlong min_jlongDouble = CONST64(0x0000000000000001);
 271 const jdouble min_jdouble = jdouble_cast(min_jlongDouble);
 272 const jlong max_jlongDouble = CONST64(0x7fefffffffffffff);
 273 const jdouble max_jdouble = jdouble_cast(max_jlongDouble);
 274 
 275 const size_t K                  = 1024;
 276 const size_t M                  = K*K;
 277 const size_t G                  = M*K;
 278 const size_t HWperKB            = K / sizeof(HeapWord);
 279 
 280 // Constants for converting from a base unit to milli-base units.  For
 281 // example from seconds to milliseconds and microseconds
 282 
 283 const int MILLIUNITS    = 1000;         // milli units per base unit
 284 const int MICROUNITS    = 1000000;      // micro units per base unit
 285 const int NANOUNITS     = 1000000000;   // nano units per base unit
 286 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS;
 287 
 288 const jlong NANOSECS_PER_SEC      = CONST64(1000000000);
 289 const jint  NANOSECS_PER_MILLISEC = 1000000;
 290 
 291 
 292 // Unit conversion functions
 293 // The caller is responsible for considering overlow.
 294 
 295 inline int64_t nanos_to_millis(int64_t nanos) {
 296   return nanos / NANOUNITS_PER_MILLIUNIT;
 297 }
 298 inline int64_t millis_to_nanos(int64_t millis) {
 299   return millis * NANOUNITS_PER_MILLIUNIT;
 300 }
 301 
 302 // Proper units routines try to maintain at least three significant digits.
 303 // In worst case, it would print five significant digits with lower prefix.
 304 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow,
 305 // and therefore we need to be careful.
 306 
 307 inline const char* proper_unit_for_byte_size(size_t s) {
 308 #ifdef _LP64
 309   if (s >= 100*G) {
 310     return "G";
 311   }
 312 #endif
 313   if (s >= 100*M) {
 314     return "M";
 315   } else if (s >= 100*K) {
 316     return "K";
 317   } else {
 318     return "B";
 319   }
 320 }
 321 
 322 template <class T>
 323 inline T byte_size_in_proper_unit(T s) {
 324 #ifdef _LP64
 325   if (s >= 100*G) {
 326     return (T)(s/G);
 327   }
 328 #endif
 329   if (s >= 100*M) {
 330     return (T)(s/M);
 331   } else if (s >= 100*K) {
 332     return (T)(s/K);
 333   } else {
 334     return s;
 335   }
 336 }
 337 
 338 inline const char* exact_unit_for_byte_size(size_t s) {
 339 #ifdef _LP64
 340   if (s >= G && (s % G) == 0) {
 341     return "G";
 342   }
 343 #endif
 344   if (s >= M && (s % M) == 0) {
 345     return "M";
 346   }
 347   if (s >= K && (s % K) == 0) {
 348     return "K";
 349   }
 350   return "B";
 351 }
 352 
 353 inline size_t byte_size_in_exact_unit(size_t s) {
 354 #ifdef _LP64
 355   if (s >= G && (s % G) == 0) {
 356     return s / G;
 357   }
 358 #endif
 359   if (s >= M && (s % M) == 0) {
 360     return s / M;
 361   }
 362   if (s >= K && (s % K) == 0) {
 363     return s / K;
 364   }
 365   return s;
 366 }
 367 
 368 // Memory size transition formatting.
 369 
 370 #define HEAP_CHANGE_FORMAT "%s: " SIZE_FORMAT "K(" SIZE_FORMAT "K)->" SIZE_FORMAT "K(" SIZE_FORMAT "K)"
 371 
 372 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \
 373   (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K
 374 
 375 //----------------------------------------------------------------------------------------------------
 376 // VM type definitions
 377 
 378 // intx and uintx are the 'extended' int and 'extended' unsigned int types;
 379 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.
 380 
 381 typedef intptr_t  intx;
 382 typedef uintptr_t uintx;
 383 
 384 const intx  min_intx  = (intx)1 << (sizeof(intx)*BitsPerByte-1);
 385 const intx  max_intx  = (uintx)min_intx - 1;
 386 const uintx max_uintx = (uintx)-1;
 387 
 388 // Table of values:
 389 //      sizeof intx         4               8
 390 // min_intx             0x80000000      0x8000000000000000
 391 // max_intx             0x7FFFFFFF      0x7FFFFFFFFFFFFFFF
 392 // max_uintx            0xFFFFFFFF      0xFFFFFFFFFFFFFFFF
 393 
 394 typedef unsigned int uint;   NEEDS_CLEANUP
 395 
 396 
 397 //----------------------------------------------------------------------------------------------------
 398 // Java type definitions
 399 
 400 // All kinds of 'plain' byte addresses
 401 typedef   signed char s_char;
 402 typedef unsigned char u_char;
 403 typedef u_char*       address;
 404 typedef uintptr_t     address_word; // unsigned integer which will hold a pointer
 405                                     // except for some implementations of a C++
 406                                     // linkage pointer to function. Should never
 407                                     // need one of those to be placed in this
 408                                     // type anyway.
 409 
 410 //  Utility functions to "portably" (?) bit twiddle pointers
 411 //  Where portable means keep ANSI C++ compilers quiet
 412 
 413 inline address       set_address_bits(address x, int m)       { return address(intptr_t(x) | m); }
 414 inline address       clear_address_bits(address x, int m)     { return address(intptr_t(x) & ~m); }
 415 
 416 //  Utility functions to "portably" make cast to/from function pointers.
 417 
 418 inline address_word  mask_address_bits(address x, int m)      { return address_word(x) & m; }
 419 inline address_word  castable_address(address x)              { return address_word(x) ; }
 420 inline address_word  castable_address(void* x)                { return address_word(x) ; }
 421 
 422 // Pointer subtraction.
 423 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have
 424 // the range we might need to find differences from one end of the heap
 425 // to the other.
 426 // A typical use might be:
 427 //     if (pointer_delta(end(), top()) >= size) {
 428 //       // enough room for an object of size
 429 //       ...
 430 // and then additions like
 431 //       ... top() + size ...
 432 // are safe because we know that top() is at least size below end().
 433 inline size_t pointer_delta(const volatile void* left,
 434                             const volatile void* right,
 435                             size_t element_size) {
 436   assert(left >= right, "avoid underflow - left: " PTR_FORMAT " right: " PTR_FORMAT, p2i(left), p2i(right));
 437   return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;
 438 }
 439 
 440 // A version specialized for HeapWord*'s.
 441 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {
 442   return pointer_delta(left, right, sizeof(HeapWord));
 443 }
 444 // A version specialized for MetaWord*'s.
 445 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) {
 446   return pointer_delta(left, right, sizeof(MetaWord));
 447 }
 448 
 449 //
 450 // ANSI C++ does not allow casting from one pointer type to a function pointer
 451 // directly without at best a warning. This macro accomplishes it silently
 452 // In every case that is present at this point the value be cast is a pointer
 453 // to a C linkage function. In some case the type used for the cast reflects
 454 // that linkage and a picky compiler would not complain. In other cases because
 455 // there is no convenient place to place a typedef with extern C linkage (i.e
 456 // a platform dependent header file) it doesn't. At this point no compiler seems
 457 // picky enough to catch these instances (which are few). It is possible that
 458 // using templates could fix these for all cases. This use of templates is likely
 459 // so far from the middle of the road that it is likely to be problematic in
 460 // many C++ compilers.
 461 //
 462 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value))
 463 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((address_word)(func_ptr)))
 464 
 465 // In many places we've added C-style casts to silence compiler
 466 // warnings, for example when truncating a size_t to an int when we
 467 // know the size_t is a small struct. Such casts are risky because
 468 // they effectively disable useful compiler warnings. We can make our
 469 // lives safer with this function, which ensures that any cast is
 470 // reversible without loss of information. It doesn't check
 471 // everything: it isn't intended to make sure that pointer types are
 472 // compatible, for example.
 473 template <typename T2, typename T1>
 474 T2 checked_cast(T1 thing) {
 475   T2 result = static_cast<T2>(thing);
 476   assert(static_cast<T1>(result) == thing, "must be");
 477   return result;
 478 }
 479 
 480 // Need the correct linkage to call qsort without warnings
 481 extern "C" {
 482   typedef int (*_sort_Fn)(const void *, const void *);
 483 }
 484 
 485 // Unsigned byte types for os and stream.hpp
 486 
 487 // Unsigned one, two, four and eigth byte quantities used for describing
 488 // the .class file format. See JVM book chapter 4.
 489 
 490 typedef jubyte  u1;
 491 typedef jushort u2;
 492 typedef juint   u4;
 493 typedef julong  u8;
 494 
 495 const jubyte  max_jubyte  = (jubyte)-1;  // 0xFF       largest jubyte
 496 const jushort max_jushort = (jushort)-1; // 0xFFFF     largest jushort
 497 const juint   max_juint   = (juint)-1;   // 0xFFFFFFFF largest juint
 498 const julong  max_julong  = (julong)-1;  // 0xFF....FF largest julong
 499 
 500 typedef jbyte  s1;
 501 typedef jshort s2;
 502 typedef jint   s4;
 503 typedef jlong  s8;
 504 
 505 const jbyte min_jbyte = -(1 << 7);       // smallest jbyte
 506 const jbyte max_jbyte = (1 << 7) - 1;    // largest jbyte
 507 const jshort min_jshort = -(1 << 15);    // smallest jshort
 508 const jshort max_jshort = (1 << 15) - 1; // largest jshort
 509 
 510 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
 511 const jint max_jint = (juint)min_jint - 1;                     // 0x7FFFFFFF == largest jint
 512 
 513 const jint min_jintFloat = (jint)(0x00000001);
 514 const jfloat min_jfloat = jfloat_cast(min_jintFloat);
 515 const jint max_jintFloat = (jint)(0x7f7fffff);
 516 const jfloat max_jfloat = jfloat_cast(max_jintFloat);
 517 
 518 //----------------------------------------------------------------------------------------------------
 519 // JVM spec restrictions
 520 
 521 const int max_method_code_size = 64*K - 1;  // JVM spec, 2nd ed. section 4.8.1 (p.134)
 522 
 523 //----------------------------------------------------------------------------------------------------
 524 // Object alignment, in units of HeapWords.
 525 //
 526 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and
 527 // reference fields can be naturally aligned.
 528 
 529 extern int MinObjAlignment;
 530 extern int MinObjAlignmentInBytes;
 531 extern int MinObjAlignmentInBytesMask;
 532 
 533 extern int LogMinObjAlignment;
 534 extern int LogMinObjAlignmentInBytes;
 535 
 536 const int LogKlassAlignmentInBytes = 3;
 537 const int LogKlassAlignment        = LogKlassAlignmentInBytes - LogHeapWordSize;
 538 const int KlassAlignmentInBytes    = 1 << LogKlassAlignmentInBytes;
 539 const int KlassAlignment           = KlassAlignmentInBytes / HeapWordSize;
 540 
 541 // Maximal size of heap where unscaled compression can be used. Also upper bound
 542 // for heap placement: 4GB.
 543 const  uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
 544 // Maximal size of heap where compressed oops can be used. Also upper bound for heap
 545 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes.
 546 extern uint64_t OopEncodingHeapMax;
 547 
 548 // Maximal size of compressed class space. Above this limit compression is not possible.
 549 // Also upper bound for placement of zero based class space. (Class space is further limited
 550 // to be < 3G, see arguments.cpp.)
 551 const  uint64_t KlassEncodingMetaspaceMax = (uint64_t(max_juint) + 1) << LogKlassAlignmentInBytes;
 552 
 553 // Machine dependent stuff
 554 
 555 // The maximum size of the code cache.  Can be overridden by targets.
 556 #define CODE_CACHE_SIZE_LIMIT (2*G)
 557 // Allow targets to reduce the default size of the code cache.
 558 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT
 559 
 560 #include CPU_HEADER(globalDefinitions)
 561 
 562 // To assure the IRIW property on processors that are not multiple copy
 563 // atomic, sync instructions must be issued between volatile reads to
 564 // assure their ordering, instead of after volatile stores.
 565 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models"
 566 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge)
 567 #ifdef CPU_MULTI_COPY_ATOMIC
 568 // Not needed.
 569 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false;
 570 #else
 571 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment.
 572 // Final decision is subject to JEP 188: Java Memory Model Update.
 573 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false);
 574 #endif
 575 
 576 // The expected size in bytes of a cache line, used to pad data structures.
 577 #ifndef DEFAULT_CACHE_LINE_SIZE
 578   #define DEFAULT_CACHE_LINE_SIZE 64
 579 #endif
 580 
 581 
 582 //----------------------------------------------------------------------------------------------------
 583 // Utility macros for compilers
 584 // used to silence compiler warnings
 585 
 586 #define Unused_Variable(var) var
 587 
 588 
 589 //----------------------------------------------------------------------------------------------------
 590 // Miscellaneous
 591 
 592 // 6302670 Eliminate Hotspot __fabsf dependency
 593 // All fabs() callers should call this function instead, which will implicitly
 594 // convert the operand to double, avoiding a dependency on __fabsf which
 595 // doesn't exist in early versions of Solaris 8.
 596 inline double fabsd(double value) {
 597   return fabs(value);
 598 }
 599 
 600 // Returns numerator/denominator as percentage value from 0 to 100. If denominator
 601 // is zero, return 0.0.
 602 template<typename T>
 603 inline double percent_of(T numerator, T denominator) {
 604   return denominator != 0 ? (double)numerator / denominator * 100.0 : 0.0;
 605 }
 606 
 607 //----------------------------------------------------------------------------------------------------
 608 // Special casts
 609 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern
 610 typedef union {
 611   jfloat f;
 612   jint i;
 613 } FloatIntConv;
 614 
 615 typedef union {
 616   jdouble d;
 617   jlong l;
 618   julong ul;
 619 } DoubleLongConv;
 620 
 621 inline jint    jint_cast    (jfloat  x)  { return ((FloatIntConv*)&x)->i; }
 622 inline jfloat  jfloat_cast  (jint    x)  { return ((FloatIntConv*)&x)->f; }
 623 
 624 inline jlong   jlong_cast   (jdouble x)  { return ((DoubleLongConv*)&x)->l;  }
 625 inline julong  julong_cast  (jdouble x)  { return ((DoubleLongConv*)&x)->ul; }
 626 inline jdouble jdouble_cast (jlong   x)  { return ((DoubleLongConv*)&x)->d;  }
 627 
 628 inline jint low (jlong value)                    { return jint(value); }
 629 inline jint high(jlong value)                    { return jint(value >> 32); }
 630 
 631 // the fancy casts are a hopefully portable way
 632 // to do unsigned 32 to 64 bit type conversion
 633 inline void set_low (jlong* value, jint low )    { *value &= (jlong)0xffffffff << 32;
 634                                                    *value |= (jlong)(julong)(juint)low; }
 635 
 636 inline void set_high(jlong* value, jint high)    { *value &= (jlong)(julong)(juint)0xffffffff;
 637                                                    *value |= (jlong)high       << 32; }
 638 
 639 inline jlong jlong_from(jint h, jint l) {
 640   jlong result = 0; // initialization to avoid warning
 641   set_high(&result, h);
 642   set_low(&result,  l);
 643   return result;
 644 }
 645 
 646 union jlong_accessor {
 647   jint  words[2];
 648   jlong long_value;
 649 };
 650 
 651 void basic_types_init(); // cannot define here; uses assert
 652 
 653 
 654 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 655 enum BasicType {
 656 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS.
 657   T_BOOLEAN     = JVM_T_BOOLEAN,
 658   T_CHAR        = JVM_T_CHAR,
 659   T_FLOAT       = JVM_T_FLOAT,
 660   T_DOUBLE      = JVM_T_DOUBLE,
 661   T_BYTE        = JVM_T_BYTE,
 662   T_SHORT       = JVM_T_SHORT,
 663   T_INT         = JVM_T_INT,
 664   T_LONG        = JVM_T_LONG,
 665   // The remaining values are not part of any standard.
 666   // T_OBJECT and T_VOID denote two more semantic choices
 667   // for method return values.
 668   // T_OBJECT and T_ARRAY describe signature syntax.
 669   // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe
 670   // internal references within the JVM as if they were Java
 671   // types in their own right.
 672   T_OBJECT      = 12,
 673   T_ARRAY       = 13,
 674   T_VOID        = 14,
 675   T_ADDRESS     = 15,
 676   T_NARROWOOP   = 16,
 677   T_METADATA    = 17,
 678   T_NARROWKLASS = 18,
 679   T_CONFLICT    = 19, // for stack value type with conflicting contents
 680   T_ILLEGAL     = 99
 681 };
 682 
 683 #define SIGNATURE_TYPES_DO(F, N)                \
 684     F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N)      \
 685     F(JVM_SIGNATURE_CHAR,    T_CHAR,    N)      \
 686     F(JVM_SIGNATURE_FLOAT,   T_FLOAT,   N)      \
 687     F(JVM_SIGNATURE_DOUBLE,  T_DOUBLE,  N)      \
 688     F(JVM_SIGNATURE_BYTE,    T_BYTE,    N)      \
 689     F(JVM_SIGNATURE_SHORT,   T_SHORT,   N)      \
 690     F(JVM_SIGNATURE_INT,     T_INT,     N)      \
 691     F(JVM_SIGNATURE_LONG,    T_LONG,    N)      \
 692     F(JVM_SIGNATURE_CLASS,   T_OBJECT,  N)      \
 693     F(JVM_SIGNATURE_ARRAY,   T_ARRAY,   N)      \
 694     F(JVM_SIGNATURE_VOID,    T_VOID,    N)      \
 695     /*end*/
 696 
 697 inline bool is_java_type(BasicType t) {
 698   return T_BOOLEAN <= t && t <= T_VOID;
 699 }
 700 
 701 inline bool is_java_primitive(BasicType t) {
 702   return T_BOOLEAN <= t && t <= T_LONG;
 703 }
 704 
 705 inline bool is_subword_type(BasicType t) {
 706   // these guys are processed exactly like T_INT in calling sequences:
 707   return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);
 708 }
 709 
 710 inline bool is_signed_subword_type(BasicType t) {
 711   return (t == T_BYTE || t == T_SHORT);
 712 }
 713 
 714 inline bool is_double_word_type(BasicType t) {
 715   return (t == T_DOUBLE || t == T_LONG);
 716 }
 717 
 718 inline bool is_reference_type(BasicType t) {
 719   return (t == T_OBJECT || t == T_ARRAY);
 720 }
 721 
 722 inline bool is_integral_type(BasicType t) {
 723   return is_subword_type(t) || t == T_INT || t == T_LONG;
 724 }
 725 
 726 inline bool is_floating_point_type(BasicType t) {
 727   return (t == T_FLOAT || t == T_DOUBLE);
 728 }
 729 
 730 extern char type2char_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 731 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }
 732 extern int type2size[T_CONFLICT+1];         // Map BasicType to result stack elements
 733 extern const char* type2name_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 734 inline const char* type2name(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2name_tab[t] : NULL; }
 735 extern BasicType name2type(const char* name);
 736 
 737 inline jlong max_signed_integer(BasicType bt) {
 738   if (bt == T_INT) {
 739     return max_jint;
 740   }
 741   assert(bt == T_LONG, "unsupported");
 742   return max_jlong;
 743 }
 744 
 745 inline jlong min_signed_integer(BasicType bt) {
 746   if (bt == T_INT) {
 747     return min_jint;
 748   }
 749   assert(bt == T_LONG, "unsupported");
 750   return min_jlong;
 751 }
 752 
 753 // Auxiliary math routines
 754 // least common multiple
 755 extern size_t lcm(size_t a, size_t b);
 756 
 757 
 758 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 759 enum BasicTypeSize {
 760   T_BOOLEAN_size     = 1,
 761   T_CHAR_size        = 1,
 762   T_FLOAT_size       = 1,
 763   T_DOUBLE_size      = 2,
 764   T_BYTE_size        = 1,
 765   T_SHORT_size       = 1,
 766   T_INT_size         = 1,
 767   T_LONG_size        = 2,
 768   T_OBJECT_size      = 1,
 769   T_ARRAY_size       = 1,
 770   T_NARROWOOP_size   = 1,
 771   T_NARROWKLASS_size = 1,
 772   T_VOID_size        = 0
 773 };
 774 
 775 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc.
 776 inline int parameter_type_word_count(BasicType t) {
 777   if (is_double_word_type(t))  return 2;
 778   assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please");
 779   assert(type2size[t] == 1, "must be");
 780   return 1;
 781 }
 782 
 783 // maps a BasicType to its instance field storage type:
 784 // all sub-word integral types are widened to T_INT
 785 extern BasicType type2field[T_CONFLICT+1];
 786 extern BasicType type2wfield[T_CONFLICT+1];
 787 
 788 
 789 // size in bytes
 790 enum ArrayElementSize {
 791   T_BOOLEAN_aelem_bytes     = 1,
 792   T_CHAR_aelem_bytes        = 2,
 793   T_FLOAT_aelem_bytes       = 4,
 794   T_DOUBLE_aelem_bytes      = 8,
 795   T_BYTE_aelem_bytes        = 1,
 796   T_SHORT_aelem_bytes       = 2,
 797   T_INT_aelem_bytes         = 4,
 798   T_LONG_aelem_bytes        = 8,
 799 #ifdef _LP64
 800   T_OBJECT_aelem_bytes      = 8,
 801   T_ARRAY_aelem_bytes       = 8,
 802 #else
 803   T_OBJECT_aelem_bytes      = 4,
 804   T_ARRAY_aelem_bytes       = 4,
 805 #endif
 806   T_NARROWOOP_aelem_bytes   = 4,
 807   T_NARROWKLASS_aelem_bytes = 4,
 808   T_VOID_aelem_bytes        = 0
 809 };
 810 
 811 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element
 812 #ifdef ASSERT
 813 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts
 814 #else
 815 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; }
 816 #endif
 817 
 818 
 819 // JavaValue serves as a container for arbitrary Java values.
 820 
 821 class JavaValue {
 822 
 823  public:
 824   typedef union JavaCallValue {
 825     jfloat   f;
 826     jdouble  d;
 827     jint     i;
 828     jlong    l;
 829     jobject  h;
 830     oopDesc* o;
 831   } JavaCallValue;
 832 
 833  private:
 834   BasicType _type;
 835   JavaCallValue _value;
 836 
 837  public:
 838   JavaValue(BasicType t = T_ILLEGAL) { _type = t; }
 839 
 840   JavaValue(jfloat value) {
 841     _type    = T_FLOAT;
 842     _value.f = value;
 843   }
 844 
 845   JavaValue(jdouble value) {
 846     _type    = T_DOUBLE;
 847     _value.d = value;
 848   }
 849 
 850  jfloat get_jfloat() const { return _value.f; }
 851  jdouble get_jdouble() const { return _value.d; }
 852  jint get_jint() const { return _value.i; }
 853  jlong get_jlong() const { return _value.l; }
 854  jobject get_jobject() const { return _value.h; }
 855  oopDesc* get_oop() const { return _value.o; }
 856  JavaCallValue* get_value_addr() { return &_value; }
 857  BasicType get_type() const { return _type; }
 858 
 859  void set_jfloat(jfloat f) { _value.f = f;}
 860  void set_jdouble(jdouble d) { _value.d = d;}
 861  void set_jint(jint i) { _value.i = i;}
 862  void set_jlong(jlong l) { _value.l = l;}
 863  void set_jobject(jobject h) { _value.h = h;}
 864  void set_oop(oopDesc* o) { _value.o = o;}
 865  void set_type(BasicType t) { _type = t; }
 866 
 867  jboolean get_jboolean() const { return (jboolean) (_value.i);}
 868  jbyte get_jbyte() const { return (jbyte) (_value.i);}
 869  jchar get_jchar() const { return (jchar) (_value.i);}
 870  jshort get_jshort() const { return (jshort) (_value.i);}
 871 
 872 };
 873 
 874 
 875 // TosState describes the top-of-stack state before and after the execution of
 876 // a bytecode or method. The top-of-stack value may be cached in one or more CPU
 877 // registers. The TosState corresponds to the 'machine representation' of this cached
 878 // value. There's 4 states corresponding to the JAVA types int, long, float & double
 879 // as well as a 5th state in case the top-of-stack value is actually on the top
 880 // of stack (in memory) and thus not cached. The atos state corresponds to the itos
 881 // state when it comes to machine representation but is used separately for (oop)
 882 // type specific operations (e.g. verification code).
 883 
 884 enum TosState {         // describes the tos cache contents
 885   btos = 0,             // byte, bool tos cached
 886   ztos = 1,             // byte, bool tos cached
 887   ctos = 2,             // char tos cached
 888   stos = 3,             // short tos cached
 889   itos = 4,             // int tos cached
 890   ltos = 5,             // long tos cached
 891   ftos = 6,             // float tos cached
 892   dtos = 7,             // double tos cached
 893   atos = 8,             // object cached
 894   vtos = 9,             // tos not cached
 895   number_of_states,
 896   ilgl                  // illegal state: should not occur
 897 };
 898 
 899 
 900 inline TosState as_TosState(BasicType type) {
 901   switch (type) {
 902     case T_BYTE   : return btos;
 903     case T_BOOLEAN: return ztos;
 904     case T_CHAR   : return ctos;
 905     case T_SHORT  : return stos;
 906     case T_INT    : return itos;
 907     case T_LONG   : return ltos;
 908     case T_FLOAT  : return ftos;
 909     case T_DOUBLE : return dtos;
 910     case T_VOID   : return vtos;
 911     case T_ARRAY  : // fall through
 912     case T_OBJECT : return atos;
 913     default       : return ilgl;
 914   }
 915 }
 916 
 917 inline BasicType as_BasicType(TosState state) {
 918   switch (state) {
 919     case btos : return T_BYTE;
 920     case ztos : return T_BOOLEAN;
 921     case ctos : return T_CHAR;
 922     case stos : return T_SHORT;
 923     case itos : return T_INT;
 924     case ltos : return T_LONG;
 925     case ftos : return T_FLOAT;
 926     case dtos : return T_DOUBLE;
 927     case atos : return T_OBJECT;
 928     case vtos : return T_VOID;
 929     default   : return T_ILLEGAL;
 930   }
 931 }
 932 
 933 
 934 // Helper function to convert BasicType info into TosState
 935 // Note: Cannot define here as it uses global constant at the time being.
 936 TosState as_TosState(BasicType type);
 937 
 938 
 939 // JavaThreadState keeps track of which part of the code a thread is executing in. This
 940 // information is needed by the safepoint code.
 941 //
 942 // There are 4 essential states:
 943 //
 944 //  _thread_new         : Just started, but not executed init. code yet (most likely still in OS init code)
 945 //  _thread_in_native   : In native code. This is a safepoint region, since all oops will be in jobject handles
 946 //  _thread_in_vm       : Executing in the vm
 947 //  _thread_in_Java     : Executing either interpreted or compiled Java code (or could be in a stub)
 948 //
 949 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in
 950 // a transition from one state to another. These extra states makes it possible for the safepoint code to
 951 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.
 952 //
 953 // Given a state, the xxxx_trans state can always be found by adding 1.
 954 //
 955 enum JavaThreadState {
 956   _thread_uninitialized     =  0, // should never happen (missing initialization)
 957   _thread_new               =  2, // just starting up, i.e., in process of being initialized
 958   _thread_new_trans         =  3, // corresponding transition state (not used, included for completness)
 959   _thread_in_native         =  4, // running in native code
 960   _thread_in_native_trans   =  5, // corresponding transition state
 961   _thread_in_vm             =  6, // running in VM
 962   _thread_in_vm_trans       =  7, // corresponding transition state
 963   _thread_in_Java           =  8, // running in Java or in stub code
 964   _thread_in_Java_trans     =  9, // corresponding transition state (not used, included for completness)
 965   _thread_blocked           = 10, // blocked in vm
 966   _thread_blocked_trans     = 11, // corresponding transition state
 967   _thread_max_state         = 12  // maximum thread state+1 - used for statistics allocation
 968 };
 969 
 970 //----------------------------------------------------------------------------------------------------
 971 // Special constants for debugging
 972 
 973 const jint     badInt           = -3;                       // generic "bad int" value
 974 const intptr_t badAddressVal    = -2;                       // generic "bad address" value
 975 const intptr_t badOopVal        = -1;                       // generic "bad oop" value
 976 const intptr_t badHeapOopVal    = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC
 977 const int      badStackSegVal   = 0xCA;                     // value used to zap stack segments
 978 const int      badHandleValue   = 0xBC;                     // value used to zap vm handle area
 979 const int      badResourceValue = 0xAB;                     // value used to zap resource area
 980 const int      freeBlockPad     = 0xBA;                     // value used to pad freed blocks.
 981 const int      uninitBlockPad   = 0xF1;                     // value used to zap newly malloc'd blocks.
 982 const juint    uninitMetaWordVal= 0xf7f7f7f7;               // value used to zap newly allocated metachunk
 983 const juint    badHeapWordVal   = 0xBAADBABE;               // value used to zap heap after GC
 984 const juint    badMetaWordVal   = 0xBAADFADE;               // value used to zap metadata heap after GC
 985 const int      badCodeHeapNewVal= 0xCC;                     // value used to zap Code heap at allocation
 986 const int      badCodeHeapFreeVal = 0xDD;                   // value used to zap Code heap at deallocation
 987 
 988 
 989 // (These must be implemented as #defines because C++ compilers are
 990 // not obligated to inline non-integral constants!)
 991 #define       badAddress        ((address)::badAddressVal)
 992 #define       badOop            (cast_to_oop(::badOopVal))
 993 #define       badHeapWord       (::badHeapWordVal)
 994 
 995 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)
 996 #define TASKQUEUE_SIZE (NOT_LP64(1<<14) LP64_ONLY(1<<17))
 997 
 998 //----------------------------------------------------------------------------------------------------
 999 // Utility functions for bitfield manipulations
1000 
1001 const intptr_t AllBits    = ~0; // all bits set in a word
1002 const intptr_t NoBits     =  0; // no bits set in a word
1003 const jlong    NoLongBits =  0; // no bits set in a long
1004 const intptr_t OneBit     =  1; // only right_most bit set in a word
1005 
1006 // get a word with the n.th or the right-most or left-most n bits set
1007 // (note: #define used only so that they can be used in enum constant definitions)
1008 #define nth_bit(n)        (((n) >= BitsPerWord) ? 0 : (OneBit << (n)))
1009 #define right_n_bits(n)   (nth_bit(n) - 1)
1010 
1011 // bit-operations using a mask m
1012 inline void   set_bits    (intptr_t& x, intptr_t m) { x |= m; }
1013 inline void clear_bits    (intptr_t& x, intptr_t m) { x &= ~m; }
1014 inline intptr_t mask_bits      (intptr_t  x, intptr_t m) { return x & m; }
1015 inline jlong    mask_long_bits (jlong     x, jlong    m) { return x & m; }
1016 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }
1017 
1018 // bit-operations using the n.th bit
1019 inline void    set_nth_bit(intptr_t& x, int n) { set_bits  (x, nth_bit(n)); }
1020 inline void  clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }
1021 inline bool is_set_nth_bit(intptr_t  x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }
1022 
1023 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)
1024 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {
1025   return mask_bits(x >> start_bit_no, right_n_bits(field_length));
1026 }
1027 
1028 
1029 //----------------------------------------------------------------------------------------------------
1030 // Utility functions for integers
1031 
1032 // Avoid use of global min/max macros which may cause unwanted double
1033 // evaluation of arguments.
1034 #ifdef max
1035 #undef max
1036 #endif
1037 
1038 #ifdef min
1039 #undef min
1040 #endif
1041 
1042 // It is necessary to use templates here. Having normal overloaded
1043 // functions does not work because it is necessary to provide both 32-
1044 // and 64-bit overloaded functions, which does not work, and having
1045 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)
1046 // will be even more error-prone than macros.
1047 template<class T> constexpr T MAX2(T a, T b)           { return (a > b) ? a : b; }
1048 template<class T> constexpr T MIN2(T a, T b)           { return (a < b) ? a : b; }
1049 template<class T> constexpr T MAX3(T a, T b, T c)      { return MAX2(MAX2(a, b), c); }
1050 template<class T> constexpr T MIN3(T a, T b, T c)      { return MIN2(MIN2(a, b), c); }
1051 template<class T> constexpr T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }
1052 template<class T> constexpr T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }
1053 
1054 template<class T> inline T ABS(T x)                 { return (x > 0) ? x : -x; }
1055 
1056 // Return the given value clamped to the range [min ... max]
1057 template<typename T>
1058 inline T clamp(T value, T min, T max) {
1059   assert(min <= max, "must be");
1060   return MIN2(MAX2(value, min), max);
1061 }
1062 
1063 inline bool is_odd (intx x) { return x & 1;      }
1064 inline bool is_even(intx x) { return !is_odd(x); }
1065 
1066 // abs methods which cannot overflow and so are well-defined across
1067 // the entire domain of integer types.
1068 static inline unsigned int uabs(unsigned int n) {
1069   union {
1070     unsigned int result;
1071     int value;
1072   };
1073   result = n;
1074   if (value < 0) result = 0-result;
1075   return result;
1076 }
1077 static inline julong uabs(julong n) {
1078   union {
1079     julong result;
1080     jlong value;
1081   };
1082   result = n;
1083   if (value < 0) result = 0-result;
1084   return result;
1085 }
1086 static inline julong uabs(jlong n) { return uabs((julong)n); }
1087 static inline unsigned int uabs(int n) { return uabs((unsigned int)n); }
1088 
1089 // "to" should be greater than "from."
1090 inline intx byte_size(void* from, void* to) {
1091   return (address)to - (address)from;
1092 }
1093 
1094 
1095 // Pack and extract shorts to/from ints:
1096 
1097 inline int extract_low_short_from_int(jint x) {
1098   return x & 0xffff;
1099 }
1100 
1101 inline int extract_high_short_from_int(jint x) {
1102   return (x >> 16) & 0xffff;
1103 }
1104 
1105 inline int build_int_from_shorts( jushort low, jushort high ) {
1106   return ((int)((unsigned int)high << 16) | (unsigned int)low);
1107 }
1108 
1109 // swap a & b
1110 template<class T> static void swap(T& a, T& b) {
1111   T tmp = a;
1112   a = b;
1113   b = tmp;
1114 }
1115 
1116 // array_size_impl is a function that takes a reference to T[N] and
1117 // returns a reference to char[N].  It is not ODR-used, so not defined.
1118 template<typename T, size_t N> char (&array_size_impl(T (&)[N]))[N];
1119 
1120 #define ARRAY_SIZE(array) sizeof(array_size_impl(array))
1121 
1122 //----------------------------------------------------------------------------------------------------
1123 // Sum and product which can never overflow: they wrap, just like the
1124 // Java operations.  Note that we don't intend these to be used for
1125 // general-purpose arithmetic: their purpose is to emulate Java
1126 // operations.
1127 
1128 // The goal of this code to avoid undefined or implementation-defined
1129 // behavior.  The use of an lvalue to reference cast is explicitly
1130 // permitted by Lvalues and rvalues [basic.lval].  [Section 3.10 Para
1131 // 15 in C++03]
1132 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE)  \
1133 inline TYPE NAME (TYPE in1, TYPE in2) {                 \
1134   UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \
1135   ures OP ## = static_cast<UNSIGNED_TYPE>(in2);         \
1136   return reinterpret_cast<TYPE&>(ures);                 \
1137 }
1138 
1139 JAVA_INTEGER_OP(+, java_add, jint, juint)
1140 JAVA_INTEGER_OP(-, java_subtract, jint, juint)
1141 JAVA_INTEGER_OP(*, java_multiply, jint, juint)
1142 JAVA_INTEGER_OP(+, java_add, jlong, julong)
1143 JAVA_INTEGER_OP(-, java_subtract, jlong, julong)
1144 JAVA_INTEGER_OP(*, java_multiply, jlong, julong)
1145 
1146 #undef JAVA_INTEGER_OP
1147 
1148 // Provide integer shift operations with Java semantics.  No overflow
1149 // issues - left shifts simply discard shifted out bits.  No undefined
1150 // behavior for large or negative shift quantities; instead the actual
1151 // shift distance is the argument modulo the lhs value's size in bits.
1152 // No undefined or implementation defined behavior for shifting negative
1153 // values; left shift discards bits, right shift sign extends.  We use
1154 // the same safe conversion technique as above for java_add and friends.
1155 #define JAVA_INTEGER_SHIFT_OP(OP, NAME, TYPE, XTYPE)    \
1156 inline TYPE NAME (TYPE lhs, jint rhs) {                 \
1157   const uint rhs_mask = (sizeof(TYPE) * 8) - 1;         \
1158   STATIC_ASSERT(rhs_mask == 31 || rhs_mask == 63);      \
1159   XTYPE xres = static_cast<XTYPE>(lhs);                 \
1160   xres OP ## = (rhs & rhs_mask);                        \
1161   return reinterpret_cast<TYPE&>(xres);                 \
1162 }
1163 
1164 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jint, juint)
1165 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jlong, julong)
1166 // For signed shift right, assume C++ implementation >> sign extends.
1167 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jint, jint)
1168 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jlong, jlong)
1169 // For >>> use C++ unsigned >>.
1170 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jint, juint)
1171 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jlong, julong)
1172 
1173 #undef JAVA_INTEGER_SHIFT_OP
1174 
1175 //----------------------------------------------------------------------------------------------------
1176 // The goal of this code is to provide saturating operations for int/uint.
1177 // Checks overflow conditions and saturates the result to min_jint/max_jint.
1178 #define SATURATED_INTEGER_OP(OP, NAME, TYPE1, TYPE2) \
1179 inline int NAME (TYPE1 in1, TYPE2 in2) {             \
1180   jlong res = static_cast<jlong>(in1);               \
1181   res OP ## = static_cast<jlong>(in2);               \
1182   if (res > max_jint) {                              \
1183     res = max_jint;                                  \
1184   } else if (res < min_jint) {                       \
1185     res = min_jint;                                  \
1186   }                                                  \
1187   return static_cast<int>(res);                      \
1188 }
1189 
1190 SATURATED_INTEGER_OP(+, saturated_add, int, int)
1191 SATURATED_INTEGER_OP(+, saturated_add, int, uint)
1192 SATURATED_INTEGER_OP(+, saturated_add, uint, int)
1193 SATURATED_INTEGER_OP(+, saturated_add, uint, uint)
1194 
1195 #undef SATURATED_INTEGER_OP
1196 
1197 // Dereference vptr
1198 // All C++ compilers that we know of have the vtbl pointer in the first
1199 // word.  If there are exceptions, this function needs to be made compiler
1200 // specific.
1201 static inline void* dereference_vptr(const void* addr) {
1202   return *(void**)addr;
1203 }
1204 
1205 //----------------------------------------------------------------------------------------------------
1206 // String type aliases used by command line flag declarations and
1207 // processing utilities.
1208 
1209 typedef const char* ccstr;
1210 typedef const char* ccstrlist;   // represents string arguments which accumulate
1211 
1212 //----------------------------------------------------------------------------------------------------
1213 // Default hash/equals functions used by ResourceHashtable
1214 
1215 template<typename K> unsigned primitive_hash(const K& k) {
1216   unsigned hash = (unsigned)((uintptr_t)k);
1217   return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs
1218 }
1219 
1220 template<typename K> bool primitive_equals(const K& k0, const K& k1) {
1221   return k0 == k1;
1222 }
1223 
1224 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP