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
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  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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  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 inline jfloat jfloat_cast(jint x);
 237 inline jdouble jdouble_cast(jlong x);
 238 
 239 //-------------------------------------------
 240 // Constant for jlong (standardized by C++11)
 241 
 242 // Build a 64bit integer constant
 243 #define CONST64(x)  (x ## LL)
 244 #define UCONST64(x) (x ## ULL)
 245 
 246 const jlong min_jlong = CONST64(0x8000000000000000);
 247 const jlong max_jlong = CONST64(0x7fffffffffffffff);
 248 
 249 //-------------------------------------------
 250 // Constant for jdouble
 251 const jlong min_jlongDouble = CONST64(0x0000000000000001);
 252 const jdouble min_jdouble = jdouble_cast(min_jlongDouble);
 253 const jlong max_jlongDouble = CONST64(0x7fefffffffffffff);
 254 const jdouble max_jdouble = jdouble_cast(max_jlongDouble);
 255 
 256 const size_t K                  = 1024;
 257 const size_t M                  = K*K;
 258 const size_t G                  = M*K;
 259 const size_t HWperKB            = K / sizeof(HeapWord);
 260 
 261 // Constants for converting from a base unit to milli-base units.  For
 262 // example from seconds to milliseconds and microseconds
 263 
 264 const int MILLIUNITS    = 1000;         // milli units per base unit
 265 const int MICROUNITS    = 1000000;      // micro units per base unit
 266 const int NANOUNITS     = 1000000000;   // nano units per base unit
 267 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS;
 268 
 269 const jlong NANOSECS_PER_SEC      = CONST64(1000000000);
 270 const jint  NANOSECS_PER_MILLISEC = 1000000;
 271 
 272 
 273 // Unit conversion functions
 274 // The caller is responsible for considering overlow.
 275 
 276 inline int64_t nanos_to_millis(int64_t nanos) {
 277   return nanos / NANOUNITS_PER_MILLIUNIT;
 278 }
 279 inline int64_t millis_to_nanos(int64_t millis) {
 280   return millis * NANOUNITS_PER_MILLIUNIT;
 281 }
 282 
 283 // Proper units routines try to maintain at least three significant digits.
 284 // In worst case, it would print five significant digits with lower prefix.
 285 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow,
 286 // and therefore we need to be careful.
 287 
 288 inline const char* proper_unit_for_byte_size(size_t s) {
 289 #ifdef _LP64
 290   if (s >= 100*G) {
 291     return "G";
 292   }
 293 #endif
 294   if (s >= 100*M) {
 295     return "M";
 296   } else if (s >= 100*K) {
 297     return "K";
 298   } else {
 299     return "B";
 300   }
 301 }
 302 
 303 template <class T>
 304 inline T byte_size_in_proper_unit(T s) {
 305 #ifdef _LP64
 306   if (s >= 100*G) {
 307     return (T)(s/G);
 308   }
 309 #endif
 310   if (s >= 100*M) {
 311     return (T)(s/M);
 312   } else if (s >= 100*K) {
 313     return (T)(s/K);
 314   } else {
 315     return s;
 316   }
 317 }
 318 
 319 inline const char* exact_unit_for_byte_size(size_t s) {
 320 #ifdef _LP64
 321   if (s >= G && (s % G) == 0) {
 322     return "G";
 323   }
 324 #endif
 325   if (s >= M && (s % M) == 0) {
 326     return "M";
 327   }
 328   if (s >= K && (s % K) == 0) {
 329     return "K";
 330   }
 331   return "B";
 332 }
 333 
 334 inline size_t byte_size_in_exact_unit(size_t s) {
 335 #ifdef _LP64
 336   if (s >= G && (s % G) == 0) {
 337     return s / G;
 338   }
 339 #endif
 340   if (s >= M && (s % M) == 0) {
 341     return s / M;
 342   }
 343   if (s >= K && (s % K) == 0) {
 344     return s / K;
 345   }
 346   return s;
 347 }
 348 
 349 // Memory size transition formatting.
 350 
 351 #define HEAP_CHANGE_FORMAT "%s: " SIZE_FORMAT "K(" SIZE_FORMAT "K)->" SIZE_FORMAT "K(" SIZE_FORMAT "K)"
 352 
 353 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \
 354   (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K
 355 
 356 //----------------------------------------------------------------------------------------------------
 357 // VM type definitions
 358 
 359 // intx and uintx are the 'extended' int and 'extended' unsigned int types;
 360 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.
 361 
 362 typedef intptr_t  intx;
 363 typedef uintptr_t uintx;
 364 
 365 const intx  min_intx  = (intx)1 << (sizeof(intx)*BitsPerByte-1);
 366 const intx  max_intx  = (uintx)min_intx - 1;
 367 const uintx max_uintx = (uintx)-1;
 368 
 369 // Table of values:
 370 //      sizeof intx         4               8
 371 // min_intx             0x80000000      0x8000000000000000
 372 // max_intx             0x7FFFFFFF      0x7FFFFFFFFFFFFFFF
 373 // max_uintx            0xFFFFFFFF      0xFFFFFFFFFFFFFFFF
 374 
 375 typedef unsigned int uint;   NEEDS_CLEANUP
 376 
 377 
 378 //----------------------------------------------------------------------------------------------------
 379 // Java type definitions
 380 
 381 // All kinds of 'plain' byte addresses
 382 typedef   signed char s_char;
 383 typedef unsigned char u_char;
 384 typedef u_char*       address;
 385 typedef uintptr_t     address_word; // unsigned integer which will hold a pointer
 386                                     // except for some implementations of a C++
 387                                     // linkage pointer to function. Should never
 388                                     // need one of those to be placed in this
 389                                     // type anyway.
 390 
 391 //  Utility functions to "portably" (?) bit twiddle pointers
 392 //  Where portable means keep ANSI C++ compilers quiet
 393 
 394 inline address       set_address_bits(address x, int m)       { return address(intptr_t(x) | m); }
 395 inline address       clear_address_bits(address x, int m)     { return address(intptr_t(x) & ~m); }
 396 
 397 //  Utility functions to "portably" make cast to/from function pointers.
 398 
 399 inline address_word  mask_address_bits(address x, int m)      { return address_word(x) & m; }
 400 inline address_word  castable_address(address x)              { return address_word(x) ; }
 401 inline address_word  castable_address(void* x)                { return address_word(x) ; }
 402 
 403 // Pointer subtraction.
 404 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have
 405 // the range we might need to find differences from one end of the heap
 406 // to the other.
 407 // A typical use might be:
 408 //     if (pointer_delta(end(), top()) >= size) {
 409 //       // enough room for an object of size
 410 //       ...
 411 // and then additions like
 412 //       ... top() + size ...
 413 // are safe because we know that top() is at least size below end().
 414 inline size_t pointer_delta(const volatile void* left,
 415                             const volatile void* right,
 416                             size_t element_size) {
 417   return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;
 418 }
 419 
 420 // A version specialized for HeapWord*'s.
 421 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {
 422   return pointer_delta(left, right, sizeof(HeapWord));
 423 }
 424 // A version specialized for MetaWord*'s.
 425 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) {
 426   return pointer_delta(left, right, sizeof(MetaWord));
 427 }
 428 
 429 //
 430 // ANSI C++ does not allow casting from one pointer type to a function pointer
 431 // directly without at best a warning. This macro accomplishes it silently
 432 // In every case that is present at this point the value be cast is a pointer
 433 // to a C linkage function. In some case the type used for the cast reflects
 434 // that linkage and a picky compiler would not complain. In other cases because
 435 // there is no convenient place to place a typedef with extern C linkage (i.e
 436 // a platform dependent header file) it doesn't. At this point no compiler seems
 437 // picky enough to catch these instances (which are few). It is possible that
 438 // using templates could fix these for all cases. This use of templates is likely
 439 // so far from the middle of the road that it is likely to be problematic in
 440 // many C++ compilers.
 441 //
 442 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value))
 443 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((address_word)(func_ptr)))
 444 
 445 // Need the correct linkage to call qsort without warnings
 446 extern "C" {
 447   typedef int (*_sort_Fn)(const void *, const void *);
 448 }
 449 
 450 // Unsigned byte types for os and stream.hpp
 451 
 452 // Unsigned one, two, four and eigth byte quantities used for describing
 453 // the .class file format. See JVM book chapter 4.
 454 
 455 typedef jubyte  u1;
 456 typedef jushort u2;
 457 typedef juint   u4;
 458 typedef julong  u8;
 459 
 460 const jubyte  max_jubyte  = (jubyte)-1;  // 0xFF       largest jubyte
 461 const jushort max_jushort = (jushort)-1; // 0xFFFF     largest jushort
 462 const juint   max_juint   = (juint)-1;   // 0xFFFFFFFF largest juint
 463 const julong  max_julong  = (julong)-1;  // 0xFF....FF largest julong
 464 
 465 typedef jbyte  s1;
 466 typedef jshort s2;
 467 typedef jint   s4;
 468 typedef jlong  s8;
 469 
 470 const jbyte min_jbyte = -(1 << 7);       // smallest jbyte
 471 const jbyte max_jbyte = (1 << 7) - 1;    // largest jbyte
 472 const jshort min_jshort = -(1 << 15);    // smallest jshort
 473 const jshort max_jshort = (1 << 15) - 1; // largest jshort
 474 
 475 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
 476 const jint max_jint = (juint)min_jint - 1;                     // 0x7FFFFFFF == largest jint
 477 
 478 const jint min_jintFloat = (jint)(0x00000001);
 479 const jfloat min_jfloat = jfloat_cast(min_jintFloat);
 480 const jint max_jintFloat = (jint)(0x7f7fffff);
 481 const jfloat max_jfloat = jfloat_cast(max_jintFloat);
 482 
 483 //----------------------------------------------------------------------------------------------------
 484 // JVM spec restrictions
 485 
 486 const int max_method_code_size = 64*K - 1;  // JVM spec, 2nd ed. section 4.8.1 (p.134)
 487 
 488 //----------------------------------------------------------------------------------------------------
 489 // Object alignment, in units of HeapWords.
 490 //
 491 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and
 492 // reference fields can be naturally aligned.
 493 
 494 extern int MinObjAlignment;
 495 extern int MinObjAlignmentInBytes;
 496 extern int MinObjAlignmentInBytesMask;
 497 
 498 extern int LogMinObjAlignment;
 499 extern int LogMinObjAlignmentInBytes;
 500 
 501 const int LogKlassAlignmentInBytes = 3;
 502 const int LogKlassAlignment        = LogKlassAlignmentInBytes - LogHeapWordSize;
 503 const int KlassAlignmentInBytes    = 1 << LogKlassAlignmentInBytes;
 504 const int KlassAlignment           = KlassAlignmentInBytes / HeapWordSize;
 505 
 506 // Maximal size of heap where unscaled compression can be used. Also upper bound
 507 // for heap placement: 4GB.
 508 const  uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
 509 // Maximal size of heap where compressed oops can be used. Also upper bound for heap
 510 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes.
 511 extern uint64_t OopEncodingHeapMax;
 512 
 513 // Maximal size of compressed class space. Above this limit compression is not possible.
 514 // Also upper bound for placement of zero based class space. (Class space is further limited
 515 // to be < 3G, see arguments.cpp.)
 516 const  uint64_t KlassEncodingMetaspaceMax = (uint64_t(max_juint) + 1) << LogKlassAlignmentInBytes;
 517 
 518 // Machine dependent stuff
 519 
 520 // The maximum size of the code cache.  Can be overridden by targets.
 521 #define CODE_CACHE_SIZE_LIMIT (2*G)
 522 // Allow targets to reduce the default size of the code cache.
 523 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT
 524 
 525 #include CPU_HEADER(globalDefinitions)
 526 
 527 // To assure the IRIW property on processors that are not multiple copy
 528 // atomic, sync instructions must be issued between volatile reads to
 529 // assure their ordering, instead of after volatile stores.
 530 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models"
 531 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge)
 532 #ifdef CPU_MULTI_COPY_ATOMIC
 533 // Not needed.
 534 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false;
 535 #else
 536 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment.
 537 // Final decision is subject to JEP 188: Java Memory Model Update.
 538 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false);
 539 #endif
 540 
 541 // The expected size in bytes of a cache line, used to pad data structures.
 542 #ifndef DEFAULT_CACHE_LINE_SIZE
 543   #define DEFAULT_CACHE_LINE_SIZE 64
 544 #endif
 545 
 546 
 547 //----------------------------------------------------------------------------------------------------
 548 // Utility macros for compilers
 549 // used to silence compiler warnings
 550 
 551 #define Unused_Variable(var) var
 552 
 553 
 554 //----------------------------------------------------------------------------------------------------
 555 // Miscellaneous
 556 
 557 // 6302670 Eliminate Hotspot __fabsf dependency
 558 // All fabs() callers should call this function instead, which will implicitly
 559 // convert the operand to double, avoiding a dependency on __fabsf which
 560 // doesn't exist in early versions of Solaris 8.
 561 inline double fabsd(double value) {
 562   return fabs(value);
 563 }
 564 
 565 // Returns numerator/denominator as percentage value from 0 to 100. If denominator
 566 // is zero, return 0.0.
 567 template<typename T>
 568 inline double percent_of(T numerator, T denominator) {
 569   return denominator != 0 ? (double)numerator / denominator * 100.0 : 0.0;
 570 }
 571 
 572 //----------------------------------------------------------------------------------------------------
 573 // Special casts
 574 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern
 575 typedef union {
 576   jfloat f;
 577   jint i;
 578 } FloatIntConv;
 579 
 580 typedef union {
 581   jdouble d;
 582   jlong l;
 583   julong ul;
 584 } DoubleLongConv;
 585 
 586 inline jint    jint_cast    (jfloat  x)  { return ((FloatIntConv*)&x)->i; }
 587 inline jfloat  jfloat_cast  (jint    x)  { return ((FloatIntConv*)&x)->f; }
 588 
 589 inline jlong   jlong_cast   (jdouble x)  { return ((DoubleLongConv*)&x)->l;  }
 590 inline julong  julong_cast  (jdouble x)  { return ((DoubleLongConv*)&x)->ul; }
 591 inline jdouble jdouble_cast (jlong   x)  { return ((DoubleLongConv*)&x)->d;  }
 592 
 593 inline jint low (jlong value)                    { return jint(value); }
 594 inline jint high(jlong value)                    { return jint(value >> 32); }
 595 
 596 // the fancy casts are a hopefully portable way
 597 // to do unsigned 32 to 64 bit type conversion
 598 inline void set_low (jlong* value, jint low )    { *value &= (jlong)0xffffffff << 32;
 599                                                    *value |= (jlong)(julong)(juint)low; }
 600 
 601 inline void set_high(jlong* value, jint high)    { *value &= (jlong)(julong)(juint)0xffffffff;
 602                                                    *value |= (jlong)high       << 32; }
 603 
 604 inline jlong jlong_from(jint h, jint l) {
 605   jlong result = 0; // initialization to avoid warning
 606   set_high(&result, h);
 607   set_low(&result,  l);
 608   return result;
 609 }
 610 
 611 union jlong_accessor {
 612   jint  words[2];
 613   jlong long_value;
 614 };
 615 
 616 void basic_types_init(); // cannot define here; uses assert
 617 
 618 
 619 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 620 enum BasicType {
 621 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS.
 622   T_BOOLEAN     = JVM_T_BOOLEAN,
 623   T_CHAR        = JVM_T_CHAR,
 624   T_FLOAT       = JVM_T_FLOAT,
 625   T_DOUBLE      = JVM_T_DOUBLE,
 626   T_BYTE        = JVM_T_BYTE,
 627   T_SHORT       = JVM_T_SHORT,
 628   T_INT         = JVM_T_INT,
 629   T_LONG        = JVM_T_LONG,
 630   // The remaining values are not part of any standard.
 631   // T_OBJECT and T_VOID denote two more semantic choices
 632   // for method return values.
 633   // T_OBJECT and T_ARRAY describe signature syntax.
 634   // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe
 635   // internal references within the JVM as if they were Java
 636   // types in their own right.
 637   T_OBJECT      = 12,
 638   T_ARRAY       = 13,
 639   T_VOID        = 14,
 640   T_ADDRESS     = 15,
 641   T_NARROWOOP   = 16,
 642   T_METADATA    = 17,
 643   T_NARROWKLASS = 18,
 644   T_CONFLICT    = 19, // for stack value type with conflicting contents
 645   T_ILLEGAL     = 99
 646 };
 647 
 648 #define SIGNATURE_TYPES_DO(F, N)                \
 649     F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N)      \
 650     F(JVM_SIGNATURE_CHAR,    T_CHAR,    N)      \
 651     F(JVM_SIGNATURE_FLOAT,   T_FLOAT,   N)      \
 652     F(JVM_SIGNATURE_DOUBLE,  T_DOUBLE,  N)      \
 653     F(JVM_SIGNATURE_BYTE,    T_BYTE,    N)      \
 654     F(JVM_SIGNATURE_SHORT,   T_SHORT,   N)      \
 655     F(JVM_SIGNATURE_INT,     T_INT,     N)      \
 656     F(JVM_SIGNATURE_LONG,    T_LONG,    N)      \
 657     F(JVM_SIGNATURE_CLASS,   T_OBJECT,  N)      \
 658     F(JVM_SIGNATURE_ARRAY,   T_ARRAY,   N)      \
 659     F(JVM_SIGNATURE_VOID,    T_VOID,    N)      \
 660     /*end*/
 661 
 662 inline bool is_java_type(BasicType t) {
 663   return T_BOOLEAN <= t && t <= T_VOID;
 664 }
 665 
 666 inline bool is_java_primitive(BasicType t) {
 667   return T_BOOLEAN <= t && t <= T_LONG;
 668 }
 669 
 670 inline bool is_subword_type(BasicType t) {
 671   // these guys are processed exactly like T_INT in calling sequences:
 672   return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);
 673 }
 674 
 675 inline bool is_signed_subword_type(BasicType t) {
 676   return (t == T_BYTE || t == T_SHORT);
 677 }
 678 
 679 inline bool is_double_word_type(BasicType t) {
 680   return (t == T_DOUBLE || t == T_LONG);
 681 }
 682 
 683 inline bool is_reference_type(BasicType t) {
 684   return (t == T_OBJECT || t == T_ARRAY);
 685 }
 686 
 687 inline bool is_integral_type(BasicType t) {
 688   return is_subword_type(t) || t == T_INT || t == T_LONG;
 689 }
 690 
 691 inline bool is_floating_point_type(BasicType t) {
 692   return (t == T_FLOAT || t == T_DOUBLE);
 693 }
 694 
 695 extern char type2char_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 696 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }
 697 extern int type2size[T_CONFLICT+1];         // Map BasicType to result stack elements
 698 extern const char* type2name_tab[T_CONFLICT+1];     // Map a BasicType to a jchar
 699 inline const char* type2name(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2name_tab[t] : NULL; }
 700 extern BasicType name2type(const char* name);
 701 
 702 // Auxiliary math routines
 703 // least common multiple
 704 extern size_t lcm(size_t a, size_t b);
 705 
 706 
 707 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 708 enum BasicTypeSize {
 709   T_BOOLEAN_size     = 1,
 710   T_CHAR_size        = 1,
 711   T_FLOAT_size       = 1,
 712   T_DOUBLE_size      = 2,
 713   T_BYTE_size        = 1,
 714   T_SHORT_size       = 1,
 715   T_INT_size         = 1,
 716   T_LONG_size        = 2,
 717   T_OBJECT_size      = 1,
 718   T_ARRAY_size       = 1,
 719   T_NARROWOOP_size   = 1,
 720   T_NARROWKLASS_size = 1,
 721   T_VOID_size        = 0
 722 };
 723 
 724 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc.
 725 inline int parameter_type_word_count(BasicType t) {
 726   if (is_double_word_type(t))  return 2;
 727   assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please");
 728   assert(type2size[t] == 1, "must be");
 729   return 1;
 730 }
 731 
 732 // maps a BasicType to its instance field storage type:
 733 // all sub-word integral types are widened to T_INT
 734 extern BasicType type2field[T_CONFLICT+1];
 735 extern BasicType type2wfield[T_CONFLICT+1];
 736 
 737 
 738 // size in bytes
 739 enum ArrayElementSize {
 740   T_BOOLEAN_aelem_bytes     = 1,
 741   T_CHAR_aelem_bytes        = 2,
 742   T_FLOAT_aelem_bytes       = 4,
 743   T_DOUBLE_aelem_bytes      = 8,
 744   T_BYTE_aelem_bytes        = 1,
 745   T_SHORT_aelem_bytes       = 2,
 746   T_INT_aelem_bytes         = 4,
 747   T_LONG_aelem_bytes        = 8,
 748 #ifdef _LP64
 749   T_OBJECT_aelem_bytes      = 8,
 750   T_ARRAY_aelem_bytes       = 8,
 751 #else
 752   T_OBJECT_aelem_bytes      = 4,
 753   T_ARRAY_aelem_bytes       = 4,
 754 #endif
 755   T_NARROWOOP_aelem_bytes   = 4,
 756   T_NARROWKLASS_aelem_bytes = 4,
 757   T_VOID_aelem_bytes        = 0
 758 };
 759 
 760 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element
 761 #ifdef ASSERT
 762 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts
 763 #else
 764 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; }
 765 #endif
 766 
 767 
 768 // JavaValue serves as a container for arbitrary Java values.
 769 
 770 class JavaValue {
 771 
 772  public:
 773   typedef union JavaCallValue {
 774     jfloat   f;
 775     jdouble  d;
 776     jint     i;
 777     jlong    l;
 778     jobject  h;
 779   } JavaCallValue;
 780 
 781  private:
 782   BasicType _type;
 783   JavaCallValue _value;
 784 
 785  public:
 786   JavaValue(BasicType t = T_ILLEGAL) { _type = t; }
 787 
 788   JavaValue(jfloat value) {
 789     _type    = T_FLOAT;
 790     _value.f = value;
 791   }
 792 
 793   JavaValue(jdouble value) {
 794     _type    = T_DOUBLE;
 795     _value.d = value;
 796   }
 797 
 798  jfloat get_jfloat() const { return _value.f; }
 799  jdouble get_jdouble() const { return _value.d; }
 800  jint get_jint() const { return _value.i; }
 801  jlong get_jlong() const { return _value.l; }
 802  jobject get_jobject() const { return _value.h; }
 803  JavaCallValue* get_value_addr() { return &_value; }
 804  BasicType get_type() const { return _type; }
 805 
 806  void set_jfloat(jfloat f) { _value.f = f;}
 807  void set_jdouble(jdouble d) { _value.d = d;}
 808  void set_jint(jint i) { _value.i = i;}
 809  void set_jlong(jlong l) { _value.l = l;}
 810  void set_jobject(jobject h) { _value.h = h;}
 811  void set_type(BasicType t) { _type = t; }
 812 
 813  jboolean get_jboolean() const { return (jboolean) (_value.i);}
 814  jbyte get_jbyte() const { return (jbyte) (_value.i);}
 815  jchar get_jchar() const { return (jchar) (_value.i);}
 816  jshort get_jshort() const { return (jshort) (_value.i);}
 817 
 818 };
 819 
 820 
 821 // TosState describes the top-of-stack state before and after the execution of
 822 // a bytecode or method. The top-of-stack value may be cached in one or more CPU
 823 // registers. The TosState corresponds to the 'machine representation' of this cached
 824 // value. There's 4 states corresponding to the JAVA types int, long, float & double
 825 // as well as a 5th state in case the top-of-stack value is actually on the top
 826 // of stack (in memory) and thus not cached. The atos state corresponds to the itos
 827 // state when it comes to machine representation but is used separately for (oop)
 828 // type specific operations (e.g. verification code).
 829 
 830 enum TosState {         // describes the tos cache contents
 831   btos = 0,             // byte, bool tos cached
 832   ztos = 1,             // byte, bool tos cached
 833   ctos = 2,             // char tos cached
 834   stos = 3,             // short tos cached
 835   itos = 4,             // int tos cached
 836   ltos = 5,             // long tos cached
 837   ftos = 6,             // float tos cached
 838   dtos = 7,             // double tos cached
 839   atos = 8,             // object cached
 840   vtos = 9,             // tos not cached
 841   number_of_states,
 842   ilgl                  // illegal state: should not occur
 843 };
 844 
 845 
 846 inline TosState as_TosState(BasicType type) {
 847   switch (type) {
 848     case T_BYTE   : return btos;
 849     case T_BOOLEAN: return ztos;
 850     case T_CHAR   : return ctos;
 851     case T_SHORT  : return stos;
 852     case T_INT    : return itos;
 853     case T_LONG   : return ltos;
 854     case T_FLOAT  : return ftos;
 855     case T_DOUBLE : return dtos;
 856     case T_VOID   : return vtos;
 857     case T_ARRAY  : // fall through
 858     case T_OBJECT : return atos;
 859     default       : return ilgl;
 860   }
 861 }
 862 
 863 inline BasicType as_BasicType(TosState state) {
 864   switch (state) {
 865     case btos : return T_BYTE;
 866     case ztos : return T_BOOLEAN;
 867     case ctos : return T_CHAR;
 868     case stos : return T_SHORT;
 869     case itos : return T_INT;
 870     case ltos : return T_LONG;
 871     case ftos : return T_FLOAT;
 872     case dtos : return T_DOUBLE;
 873     case atos : return T_OBJECT;
 874     case vtos : return T_VOID;
 875     default   : return T_ILLEGAL;
 876   }
 877 }
 878 
 879 
 880 // Helper function to convert BasicType info into TosState
 881 // Note: Cannot define here as it uses global constant at the time being.
 882 TosState as_TosState(BasicType type);
 883 
 884 
 885 // JavaThreadState keeps track of which part of the code a thread is executing in. This
 886 // information is needed by the safepoint code.
 887 //
 888 // There are 4 essential states:
 889 //
 890 //  _thread_new         : Just started, but not executed init. code yet (most likely still in OS init code)
 891 //  _thread_in_native   : In native code. This is a safepoint region, since all oops will be in jobject handles
 892 //  _thread_in_vm       : Executing in the vm
 893 //  _thread_in_Java     : Executing either interpreted or compiled Java code (or could be in a stub)
 894 //
 895 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in
 896 // a transition from one state to another. These extra states makes it possible for the safepoint code to
 897 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.
 898 //
 899 // Given a state, the xxxx_trans state can always be found by adding 1.
 900 //
 901 enum JavaThreadState {
 902   _thread_uninitialized     =  0, // should never happen (missing initialization)
 903   _thread_new               =  2, // just starting up, i.e., in process of being initialized
 904   _thread_new_trans         =  3, // corresponding transition state (not used, included for completness)
 905   _thread_in_native         =  4, // running in native code
 906   _thread_in_native_trans   =  5, // corresponding transition state
 907   _thread_in_vm             =  6, // running in VM
 908   _thread_in_vm_trans       =  7, // corresponding transition state
 909   _thread_in_Java           =  8, // running in Java or in stub code
 910   _thread_in_Java_trans     =  9, // corresponding transition state (not used, included for completness)
 911   _thread_blocked           = 10, // blocked in vm
 912   _thread_blocked_trans     = 11, // corresponding transition state
 913   _thread_max_state         = 12  // maximum thread state+1 - used for statistics allocation
 914 };
 915 
 916 //----------------------------------------------------------------------------------------------------
 917 // Special constants for debugging
 918 
 919 const jint     badInt           = -3;                       // generic "bad int" value
 920 const intptr_t badAddressVal    = -2;                       // generic "bad address" value
 921 const intptr_t badOopVal        = -1;                       // generic "bad oop" value
 922 const intptr_t badHeapOopVal    = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC
 923 const int      badStackSegVal   = 0xCA;                     // value used to zap stack segments
 924 const int      badHandleValue   = 0xBC;                     // value used to zap vm handle area
 925 const int      badResourceValue = 0xAB;                     // value used to zap resource area
 926 const int      freeBlockPad     = 0xBA;                     // value used to pad freed blocks.
 927 const int      uninitBlockPad   = 0xF1;                     // value used to zap newly malloc'd blocks.
 928 const juint    uninitMetaWordVal= 0xf7f7f7f7;               // value used to zap newly allocated metachunk
 929 const juint    badHeapWordVal   = 0xBAADBABE;               // value used to zap heap after GC
 930 const juint    badMetaWordVal   = 0xBAADFADE;               // value used to zap metadata heap after GC
 931 const int      badCodeHeapNewVal= 0xCC;                     // value used to zap Code heap at allocation
 932 const int      badCodeHeapFreeVal = 0xDD;                   // value used to zap Code heap at deallocation
 933 
 934 
 935 // (These must be implemented as #defines because C++ compilers are
 936 // not obligated to inline non-integral constants!)
 937 #define       badAddress        ((address)::badAddressVal)
 938 #define       badOop            (cast_to_oop(::badOopVal))
 939 #define       badHeapWord       (::badHeapWordVal)
 940 
 941 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)
 942 #define TASKQUEUE_SIZE (NOT_LP64(1<<14) LP64_ONLY(1<<17))
 943 
 944 //----------------------------------------------------------------------------------------------------
 945 // Utility functions for bitfield manipulations
 946 
 947 const intptr_t AllBits    = ~0; // all bits set in a word
 948 const intptr_t NoBits     =  0; // no bits set in a word
 949 const jlong    NoLongBits =  0; // no bits set in a long
 950 const intptr_t OneBit     =  1; // only right_most bit set in a word
 951 
 952 // get a word with the n.th or the right-most or left-most n bits set
 953 // (note: #define used only so that they can be used in enum constant definitions)
 954 #define nth_bit(n)        (((n) >= BitsPerWord) ? 0 : (OneBit << (n)))
 955 #define right_n_bits(n)   (nth_bit(n) - 1)
 956 #define left_n_bits(n)    (right_n_bits(n) << (((n) >= BitsPerWord) ? 0 : (BitsPerWord - (n))))
 957 
 958 // bit-operations using a mask m
 959 inline void   set_bits    (intptr_t& x, intptr_t m) { x |= m; }
 960 inline void clear_bits    (intptr_t& x, intptr_t m) { x &= ~m; }
 961 inline intptr_t mask_bits      (intptr_t  x, intptr_t m) { return x & m; }
 962 inline jlong    mask_long_bits (jlong     x, jlong    m) { return x & m; }
 963 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }
 964 
 965 // bit-operations using the n.th bit
 966 inline void    set_nth_bit(intptr_t& x, int n) { set_bits  (x, nth_bit(n)); }
 967 inline void  clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }
 968 inline bool is_set_nth_bit(intptr_t  x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }
 969 
 970 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)
 971 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {
 972   return mask_bits(x >> start_bit_no, right_n_bits(field_length));
 973 }
 974 
 975 
 976 //----------------------------------------------------------------------------------------------------
 977 // Utility functions for integers
 978 
 979 // Avoid use of global min/max macros which may cause unwanted double
 980 // evaluation of arguments.
 981 #ifdef max
 982 #undef max
 983 #endif
 984 
 985 #ifdef min
 986 #undef min
 987 #endif
 988 
 989 // It is necessary to use templates here. Having normal overloaded
 990 // functions does not work because it is necessary to provide both 32-
 991 // and 64-bit overloaded functions, which does not work, and having
 992 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)
 993 // will be even more error-prone than macros.
 994 template<class T> inline T MAX2(T a, T b)           { return (a > b) ? a : b; }
 995 template<class T> inline T MIN2(T a, T b)           { return (a < b) ? a : b; }
 996 template<class T> inline T MAX3(T a, T b, T c)      { return MAX2(MAX2(a, b), c); }
 997 template<class T> inline T MIN3(T a, T b, T c)      { return MIN2(MIN2(a, b), c); }
 998 template<class T> inline T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }
 999 template<class T> inline T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }
1000 
1001 template<class T> inline T ABS(T x)                 { return (x > 0) ? x : -x; }
1002 
1003 // Return the given value clamped to the range [min ... max]
1004 template<typename T>
1005 inline T clamp(T value, T min, T max) {
1006   assert(min <= max, "must be");
1007   return MIN2(MAX2(value, min), max);
1008 }
1009 
1010 // Returns largest i such that 2^i <= x.
1011 // If x == 0, the function returns -1.
1012 inline int log2_intptr(uintptr_t x) {
1013   int i = -1;
1014   uintptr_t p = 1;
1015   while (p != 0 && p <= x) {
1016     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
1017     i++; p *= 2;
1018   }
1019   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))
1020   // If p = 0, overflow has occurred and i = 31 or i = 63 (depending on the machine word size).
1021   return i;
1022 }
1023 
1024 //* largest i such that 2^i <= x
1025 inline int log2_long(julong x) {
1026   int i = -1;
1027   julong p =  1;
1028   while (p != 0 && p <= x) {
1029     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
1030     i++; p *= 2;
1031   }
1032   // p = 2^(i+1) && x < p (i.e., 2^i <= x < 2^(i+1))
1033   // (if p = 0 then overflow occurred and i = 63)
1034   return i;
1035 }
1036 
1037 // If x < 0, the function returns 31 on a 32-bit machine and 63 on a 64-bit machine.
1038 inline int log2_intptr(intptr_t x) {
1039   return log2_intptr((uintptr_t)x);
1040 }
1041 
1042 inline int log2_int(int x) {
1043   STATIC_ASSERT(sizeof(int) <= sizeof(uintptr_t));
1044   return log2_intptr((uintptr_t)(unsigned int)x);
1045 }
1046 
1047 inline int log2_jint(jint x) {
1048   STATIC_ASSERT(sizeof(jint) <= sizeof(uintptr_t));
1049   return log2_intptr((uintptr_t)(juint)x);
1050 }
1051 
1052 inline int log2_uint(uint x) {
1053   STATIC_ASSERT(sizeof(uint) <= sizeof(uintptr_t));
1054   return log2_intptr((uintptr_t)x);
1055 }
1056 
1057 //  A negative value of 'x' will return '63'
1058 inline int log2_jlong(jlong x) {
1059   STATIC_ASSERT(sizeof(jlong) <= sizeof(julong));
1060   return log2_long((julong)x);
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 // Convert pointer to intptr_t, for use in printing pointers.
1110 inline intptr_t p2i(const void * p) {
1111   return (intptr_t) p;
1112 }
1113 
1114 // swap a & b
1115 template<class T> static void swap(T& a, T& b) {
1116   T tmp = a;
1117   a = b;
1118   b = tmp;
1119 }
1120 
1121 // array_size_impl is a function that takes a reference to T[N] and
1122 // returns a reference to char[N].  It is not ODR-used, so not defined.
1123 template<typename T, size_t N> char (&array_size_impl(T (&)[N]))[N];
1124 
1125 #define ARRAY_SIZE(array) sizeof(array_size_impl(array))
1126 
1127 //----------------------------------------------------------------------------------------------------
1128 // Sum and product which can never overflow: they wrap, just like the
1129 // Java operations.  Note that we don't intend these to be used for
1130 // general-purpose arithmetic: their purpose is to emulate Java
1131 // operations.
1132 
1133 // The goal of this code to avoid undefined or implementation-defined
1134 // behavior.  The use of an lvalue to reference cast is explicitly
1135 // permitted by Lvalues and rvalues [basic.lval].  [Section 3.10 Para
1136 // 15 in C++03]
1137 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE)  \
1138 inline TYPE NAME (TYPE in1, TYPE in2) {                 \
1139   UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \
1140   ures OP ## = static_cast<UNSIGNED_TYPE>(in2);         \
1141   return reinterpret_cast<TYPE&>(ures);                 \
1142 }
1143 
1144 JAVA_INTEGER_OP(+, java_add, jint, juint)
1145 JAVA_INTEGER_OP(-, java_subtract, jint, juint)
1146 JAVA_INTEGER_OP(*, java_multiply, jint, juint)
1147 JAVA_INTEGER_OP(+, java_add, jlong, julong)
1148 JAVA_INTEGER_OP(-, java_subtract, jlong, julong)
1149 JAVA_INTEGER_OP(*, java_multiply, jlong, julong)
1150 
1151 #undef JAVA_INTEGER_OP
1152 
1153 // Provide integer shift operations with Java semantics.  No overflow
1154 // issues - left shifts simply discard shifted out bits.  No undefined
1155 // behavior for large or negative shift quantities; instead the actual
1156 // shift distance is the argument modulo the lhs value's size in bits.
1157 // No undefined or implementation defined behavior for shifting negative
1158 // values; left shift discards bits, right shift sign extends.  We use
1159 // the same safe conversion technique as above for java_add and friends.
1160 #define JAVA_INTEGER_SHIFT_OP(OP, NAME, TYPE, XTYPE)    \
1161 inline TYPE NAME (TYPE lhs, jint rhs) {                 \
1162   const uint rhs_mask = (sizeof(TYPE) * 8) - 1;         \
1163   STATIC_ASSERT(rhs_mask == 31 || rhs_mask == 63);      \
1164   XTYPE xres = static_cast<XTYPE>(lhs);                 \
1165   xres OP ## = (rhs & rhs_mask);                        \
1166   return reinterpret_cast<TYPE&>(xres);                 \
1167 }
1168 
1169 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jint, juint)
1170 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jlong, julong)
1171 // For signed shift right, assume C++ implementation >> sign extends.
1172 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jint, jint)
1173 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jlong, jlong)
1174 // For >>> use C++ unsigned >>.
1175 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jint, juint)
1176 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jlong, julong)
1177 
1178 #undef JAVA_INTEGER_SHIFT_OP
1179 
1180 //----------------------------------------------------------------------------------------------------
1181 // The goal of this code is to provide saturating operations for int/uint.
1182 // Checks overflow conditions and saturates the result to min_jint/max_jint.
1183 #define SATURATED_INTEGER_OP(OP, NAME, TYPE1, TYPE2) \
1184 inline int NAME (TYPE1 in1, TYPE2 in2) {             \
1185   jlong res = static_cast<jlong>(in1);               \
1186   res OP ## = static_cast<jlong>(in2);               \
1187   if (res > max_jint) {                              \
1188     res = max_jint;                                  \
1189   } else if (res < min_jint) {                       \
1190     res = min_jint;                                  \
1191   }                                                  \
1192   return static_cast<int>(res);                      \
1193 }
1194 
1195 SATURATED_INTEGER_OP(+, saturated_add, int, int)
1196 SATURATED_INTEGER_OP(+, saturated_add, int, uint)
1197 SATURATED_INTEGER_OP(+, saturated_add, uint, int)
1198 SATURATED_INTEGER_OP(+, saturated_add, uint, uint)
1199 
1200 #undef SATURATED_INTEGER_OP
1201 
1202 // Dereference vptr
1203 // All C++ compilers that we know of have the vtbl pointer in the first
1204 // word.  If there are exceptions, this function needs to be made compiler
1205 // specific.
1206 static inline void* dereference_vptr(const void* addr) {
1207   return *(void**)addr;
1208 }
1209 
1210 //----------------------------------------------------------------------------------------------------
1211 // String type aliases used by command line flag declarations and
1212 // processing utilities.
1213 
1214 typedef const char* ccstr;
1215 typedef const char* ccstrlist;   // represents string arguments which accumulate
1216 
1217 //----------------------------------------------------------------------------------------------------
1218 // Default hash/equals functions used by ResourceHashtable and KVHashtable
1219 
1220 template<typename K> unsigned primitive_hash(const K& k) {
1221   unsigned hash = (unsigned)((uintptr_t)k);
1222   return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs
1223 }
1224 
1225 template<typename K> bool primitive_equals(const K& k0, const K& k1) {
1226   return k0 == k1;
1227 }
1228 
1229 
1230 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP