1 /* 2 * Copyright (c) 1997, 2025, 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/forbiddenFunctions.hpp" 31 #include "utilities/macros.hpp" 32 33 // Get constants like JVM_T_CHAR and JVM_SIGNATURE_INT, before pulling in <jvm.h>. 34 #include "classfile_constants.h" 35 36 #include COMPILER_HEADER(utilities/globalDefinitions) 37 38 #include <cstddef> 39 #include <cstdint> 40 #include <limits> 41 #include <type_traits> 42 43 class oopDesc; 44 45 // Defaults for macros that might be defined per compiler. 46 #ifndef NOINLINE 47 #define NOINLINE 48 #endif 49 #ifndef ALWAYSINLINE 50 #define ALWAYSINLINE inline 51 #endif 52 53 #ifndef ATTRIBUTE_ALIGNED 54 #define ATTRIBUTE_ALIGNED(x) alignas(x) 55 #endif 56 57 #ifndef ATTRIBUTE_FLATTEN 58 #define ATTRIBUTE_FLATTEN 59 #endif 60 61 // These are #defines to selectively turn on/off the Print(Opto)Assembly 62 // capabilities. Choices should be led by a tradeoff between 63 // code size and improved supportability. 64 // if PRINT_ASSEMBLY then PRINT_ABSTRACT_ASSEMBLY must be true as well 65 // to have a fallback in case hsdis is not available. 66 #if defined(PRODUCT) 67 #define SUPPORT_ABSTRACT_ASSEMBLY 68 #define SUPPORT_ASSEMBLY 69 #undef SUPPORT_OPTO_ASSEMBLY // Can't activate. In PRODUCT, many dump methods are missing. 70 #undef SUPPORT_DATA_STRUCTS // Of limited use. In PRODUCT, many print methods are empty. 71 #else 72 #define SUPPORT_ABSTRACT_ASSEMBLY 73 #define SUPPORT_ASSEMBLY 74 #define SUPPORT_OPTO_ASSEMBLY 75 #define SUPPORT_DATA_STRUCTS 76 #endif 77 #if defined(SUPPORT_ASSEMBLY) && !defined(SUPPORT_ABSTRACT_ASSEMBLY) 78 #define SUPPORT_ABSTRACT_ASSEMBLY 79 #endif 80 81 // This file holds all globally used constants & types, class (forward) 82 // declarations and a few frequently used utility functions. 83 84 // Declare the named class to be noncopyable. This macro must be followed by 85 // a semi-colon. The macro provides deleted declarations for the class's copy 86 // constructor and assignment operator. Because these operations are deleted, 87 // they cannot be defined and potential callers will fail to compile. 88 #define NONCOPYABLE(C) C(C const&) = delete; C& operator=(C const&) = delete /* next token must be ; */ 89 90 91 //---------------------------------------------------------------------------------------------------- 92 // Printf-style formatters for fixed- and variable-width types as pointers and 93 // integers. These are derived from the definitions in inttypes.h. If the platform 94 // doesn't provide appropriate definitions, they should be provided in 95 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp) 96 97 // Guide to the suffixes used in the format specifiers for integers: 98 // - print the decimal value: 745565 99 // _X - print as hexadecimal, without leading 0s: 0x12345 100 // _X_0 - print as hexadecimal, with leading 0s: 0x00012345 101 // _W(w) - prints w sized string with the given value right 102 // adjusted. Use -w to print left adjusted. 103 // _0 - print as hexadecimal, with leading 0s, without 0x prefix: 0012345 104 // 105 // Note that the PTR format specifiers print using 0x with leading zeros, 106 // just like the _X_0 version for integers. 107 108 // Format 8-bit quantities. 109 #define INT8_FORMAT_X_0 "0x%02" PRIx8 110 #define UINT8_FORMAT_X_0 "0x%02" PRIx8 111 112 // Format 16-bit quantities. 113 #define INT16_FORMAT_X_0 "0x%04" PRIx16 114 #define UINT16_FORMAT_X_0 "0x%04" PRIx16 115 116 // Format 32-bit quantities. 117 #define INT32_FORMAT "%" PRId32 118 #define INT32_FORMAT_X "0x%" PRIx32 119 #define INT32_FORMAT_X_0 "0x%08" PRIx32 120 #define INT32_FORMAT_W(width) "%" #width PRId32 121 #define UINT32_FORMAT "%" PRIu32 122 #define UINT32_FORMAT_X "0x%" PRIx32 123 #define UINT32_FORMAT_X_0 "0x%08" PRIx32 124 #define UINT32_FORMAT_W(width) "%" #width PRIu32 125 126 // Format 64-bit quantities. 127 #define INT64_FORMAT "%" PRId64 128 #define INT64_PLUS_FORMAT "%+" PRId64 129 #define INT64_FORMAT_X "0x%" PRIx64 130 #define INT64_FORMAT_X_0 "0x%016" PRIx64 131 #define INT64_FORMAT_W(width) "%" #width PRId64 132 #define UINT64_FORMAT "%" PRIu64 133 #define UINT64_FORMAT_X "0x%" PRIx64 134 #define UINT64_FORMAT_X_0 "0x%016" PRIx64 135 #define UINT64_FORMAT_W(width) "%" #width PRIu64 136 #define UINT64_FORMAT_0 "%016" PRIx64 137 138 // Format jlong, if necessary 139 #ifndef JLONG_FORMAT 140 #define JLONG_FORMAT INT64_FORMAT 141 #endif 142 #ifndef JLONG_FORMAT_W 143 #define JLONG_FORMAT_W(width) INT64_FORMAT_W(width) 144 #endif 145 #ifndef JULONG_FORMAT 146 #define JULONG_FORMAT UINT64_FORMAT 147 #endif 148 #ifndef JULONG_FORMAT_X 149 #define JULONG_FORMAT_X UINT64_FORMAT_X 150 #endif 151 152 // Format pointers and padded integral values which change size between 32- and 64-bit. 153 #ifdef _LP64 154 #define INTPTR_FORMAT "0x%016" PRIxPTR 155 #define PTR_FORMAT "0x%016" PRIxPTR 156 #define UINTX_FORMAT_X_0 "0x%016" PRIxPTR 157 #define SIZE_FORMAT_X_0 "0x%016" PRIxPTR 158 #else // !_LP64 159 #define INTPTR_FORMAT "0x%08" PRIxPTR 160 #define PTR_FORMAT "0x%08" PRIxPTR 161 #define UINTX_FORMAT_X_0 "0x%08" PRIxPTR 162 #define SIZE_FORMAT_X_0 "0x%08" PRIxPTR 163 #endif // _LP64 164 165 // Convert pointer to intptr_t, for use in printing pointers. 166 inline intptr_t p2i(const volatile void* p) { 167 return (intptr_t) p; 168 } 169 170 // Convert pointer to uintptr_t 171 inline uintptr_t p2u(const volatile void* p) { 172 return (uintptr_t) p; 173 } 174 175 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false") 176 177 //---------------------------------------------------------------------------------------------------- 178 // Constants 179 180 const int LogBytesPerShort = 1; 181 const int LogBytesPerInt = 2; 182 #ifdef _LP64 183 constexpr int LogBytesPerWord = 3; 184 #else 185 constexpr int LogBytesPerWord = 2; 186 #endif 187 const int LogBytesPerLong = 3; 188 189 const int BytesPerShort = 1 << LogBytesPerShort; 190 const int BytesPerInt = 1 << LogBytesPerInt; 191 const int BytesPerWord = 1 << LogBytesPerWord; 192 const int BytesPerLong = 1 << LogBytesPerLong; 193 194 constexpr int LogBitsPerByte = 3; 195 const int LogBitsPerShort = LogBitsPerByte + LogBytesPerShort; 196 const int LogBitsPerInt = LogBitsPerByte + LogBytesPerInt; 197 constexpr int LogBitsPerWord = LogBitsPerByte + LogBytesPerWord; 198 const int LogBitsPerLong = LogBitsPerByte + LogBytesPerLong; 199 200 const int BitsPerByte = 1 << LogBitsPerByte; 201 const int BitsPerShort = 1 << LogBitsPerShort; 202 const int BitsPerInt = 1 << LogBitsPerInt; 203 constexpr int BitsPerWord = 1 << LogBitsPerWord; 204 const int BitsPerLong = 1 << LogBitsPerLong; 205 206 const int WordAlignmentMask = (1 << LogBytesPerWord) - 1; 207 const int LongAlignmentMask = (1 << LogBytesPerLong) - 1; 208 209 const int oopSize = sizeof(char*); // Full-width oop 210 extern int heapOopSize; // Oop within a java object 211 const int wordSize = sizeof(char*); 212 const int longSize = sizeof(jlong); 213 const int jintSize = sizeof(jint); 214 const int size_tSize = sizeof(size_t); 215 216 const int BytesPerOop = BytesPerWord; // Full-width oop 217 218 extern int LogBytesPerHeapOop; // Oop within a java object 219 extern int LogBitsPerHeapOop; 220 extern int BytesPerHeapOop; 221 extern int BitsPerHeapOop; 222 223 const int BitsPerJavaInteger = 32; 224 const int BitsPerJavaLong = 64; 225 const int BitsPerSize_t = size_tSize * BitsPerByte; 226 227 // Size of a char[] needed to represent a jint as a string in decimal. 228 const int jintAsStringSize = 12; 229 230 // An opaque type, so that HeapWord* can be a generic pointer into the heap. 231 // We require that object sizes be measured in units of heap words (e.g. 232 // pointer-sized values), so that given HeapWord* hw, 233 // hw += oop(hw)->foo(); 234 // works, where foo is a method (like size or scavenge) that returns the 235 // object size. 236 class HeapWordImpl; // Opaque, never defined. 237 typedef HeapWordImpl* HeapWord; 238 239 // Analogous opaque struct for metadata allocated from metaspaces. 240 class MetaWordImpl; // Opaque, never defined. 241 typedef MetaWordImpl* MetaWord; 242 243 // HeapWordSize must be 2^LogHeapWordSize. 244 const int HeapWordSize = sizeof(HeapWord); 245 #ifdef _LP64 246 const int LogHeapWordSize = 3; 247 #else 248 const int LogHeapWordSize = 2; 249 #endif 250 const int HeapWordsPerLong = BytesPerLong / HeapWordSize; 251 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize; 252 253 // The minimum number of native machine words necessary to contain "byte_size" 254 // bytes. 255 inline size_t heap_word_size(size_t byte_size) { 256 return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize; 257 } 258 259 inline jfloat jfloat_cast(jint x); 260 inline jdouble jdouble_cast(jlong x); 261 262 //------------------------------------------- 263 // Constant for jlong (standardized by C++11) 264 265 // Build a 64bit integer constant 266 #define CONST64(x) (x ## LL) 267 #define UCONST64(x) (x ## ULL) 268 269 const jlong min_jlong = CONST64(0x8000000000000000); 270 const jlong max_jlong = CONST64(0x7fffffffffffffff); 271 272 // for timer info max values which include all bits, 0xffffffffffffffff 273 const jlong all_bits_jlong = ~jlong(0); 274 275 //------------------------------------------- 276 // Constant for jdouble 277 const jlong min_jlongDouble = CONST64(0x0000000000000001); 278 const jdouble min_jdouble = jdouble_cast(min_jlongDouble); 279 const jlong max_jlongDouble = CONST64(0x7fefffffffffffff); 280 const jdouble max_jdouble = jdouble_cast(max_jlongDouble); 281 282 const size_t K = 1024; 283 const size_t M = K*K; 284 const size_t G = M*K; 285 286 // Constants for converting from a base unit to milli-base units. For 287 // example from seconds to milliseconds and microseconds 288 289 const int MILLIUNITS = 1000; // milli units per base unit 290 const int MICROUNITS = 1000000; // micro units per base unit 291 const int NANOUNITS = 1000000000; // nano units per base unit 292 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS; 293 294 const jlong NANOSECS_PER_SEC = CONST64(1000000000); 295 const jint NANOSECS_PER_MILLISEC = 1000000; 296 297 298 // Unit conversion functions 299 // The caller is responsible for considering overflow. 300 301 inline int64_t nanos_to_millis(int64_t nanos) { 302 return nanos / NANOUNITS_PER_MILLIUNIT; 303 } 304 inline int64_t millis_to_nanos(int64_t millis) { 305 return millis * NANOUNITS_PER_MILLIUNIT; 306 } 307 308 // Proper units routines try to maintain at least three significant digits. 309 // In worst case, it would print five significant digits with lower prefix. 310 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow, 311 // and therefore we need to be careful. 312 313 inline const char* proper_unit_for_byte_size(size_t s) { 314 #ifdef _LP64 315 if (s >= 100*G) { 316 return "G"; 317 } 318 #endif 319 if (s >= 100*M) { 320 return "M"; 321 } else if (s >= 100*K) { 322 return "K"; 323 } else { 324 return "B"; 325 } 326 } 327 328 template <class T> 329 inline T byte_size_in_proper_unit(T s) { 330 #ifdef _LP64 331 if (s >= 100*G) { 332 return (T)(s/G); 333 } 334 #endif 335 if (s >= 100*M) { 336 return (T)(s/M); 337 } else if (s >= 100*K) { 338 return (T)(s/K); 339 } else { 340 return s; 341 } 342 } 343 344 #define PROPERFMT "%zu%s" 345 #define PROPERFMTARGS(s) byte_size_in_proper_unit(s), proper_unit_for_byte_size(s) 346 347 // Printing a range, with start and bytes given 348 #define RANGEFMT "[" PTR_FORMAT " - " PTR_FORMAT "), (%zu bytes)" 349 #define RANGEFMTARGS(p1, size) p2i(p1), p2i(p1 + size), size 350 351 // Printing a range, with start and end given 352 #define RANGE2FMT "[" PTR_FORMAT " - " PTR_FORMAT "), (%zu bytes)" 353 #define RANGE2FMTARGS(p1, p2) p2i(p1), p2i(p2), ((uintptr_t)p2 - (uintptr_t)p1) 354 355 inline const char* exact_unit_for_byte_size(size_t s) { 356 #ifdef _LP64 357 if (s >= G && (s % G) == 0) { 358 return "G"; 359 } 360 #endif 361 if (s >= M && (s % M) == 0) { 362 return "M"; 363 } 364 if (s >= K && (s % K) == 0) { 365 return "K"; 366 } 367 return "B"; 368 } 369 370 inline size_t byte_size_in_exact_unit(size_t s) { 371 #ifdef _LP64 372 if (s >= G && (s % G) == 0) { 373 return s / G; 374 } 375 #endif 376 if (s >= M && (s % M) == 0) { 377 return s / M; 378 } 379 if (s >= K && (s % K) == 0) { 380 return s / K; 381 } 382 return s; 383 } 384 385 #define EXACTFMT "%zu%s" 386 #define EXACTFMTARGS(s) byte_size_in_exact_unit(s), exact_unit_for_byte_size(s) 387 388 // Memory size transition formatting. 389 390 #define HEAP_CHANGE_FORMAT "%s: %zuK(%zuK)->%zuK(%zuK)" 391 392 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \ 393 (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K 394 395 //---------------------------------------------------------------------------------------------------- 396 // VM type definitions 397 398 // intx and uintx are the 'extended' int and 'extended' unsigned int types; 399 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform. 400 401 typedef intptr_t intx; 402 typedef uintptr_t uintx; 403 404 const intx min_intx = (intx)1 << (sizeof(intx)*BitsPerByte-1); 405 const intx max_intx = (uintx)min_intx - 1; 406 const uintx max_uintx = (uintx)-1; 407 408 // Table of values: 409 // sizeof intx 4 8 410 // min_intx 0x80000000 0x8000000000000000 411 // max_intx 0x7FFFFFFF 0x7FFFFFFFFFFFFFFF 412 // max_uintx 0xFFFFFFFF 0xFFFFFFFFFFFFFFFF 413 414 typedef unsigned int uint; NEEDS_CLEANUP 415 416 //---------------------------------------------------------------------------------------------------- 417 // Java type definitions 418 419 // All kinds of 'plain' byte addresses 420 typedef signed char s_char; 421 typedef unsigned char u_char; 422 typedef u_char* address; 423 typedef const u_char* const_address; 424 425 // Pointer subtraction. 426 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have 427 // the range we might need to find differences from one end of the heap 428 // to the other. 429 // A typical use might be: 430 // if (pointer_delta(end(), top()) >= size) { 431 // // enough room for an object of size 432 // ... 433 // and then additions like 434 // ... top() + size ... 435 // are safe because we know that top() is at least size below end(). 436 inline size_t pointer_delta(const volatile void* left, 437 const volatile void* right, 438 size_t element_size) { 439 assert(left >= right, "avoid underflow - left: " PTR_FORMAT " right: " PTR_FORMAT, p2i(left), p2i(right)); 440 return (((uintptr_t) left) - ((uintptr_t) right)) / element_size; 441 } 442 443 // A version specialized for HeapWord*'s. 444 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) { 445 return pointer_delta(left, right, sizeof(HeapWord)); 446 } 447 // A version specialized for MetaWord*'s. 448 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) { 449 return pointer_delta(left, right, sizeof(MetaWord)); 450 } 451 452 // pointer_delta_as_int is called to do pointer subtraction for nearby pointers that 453 // returns a non-negative int, usually used as a size of a code buffer range. 454 // This scales to sizeof(T). 455 template <typename T> 456 inline int pointer_delta_as_int(const volatile T* left, const volatile T* right) { 457 size_t delta = pointer_delta(left, right, sizeof(T)); 458 assert(delta <= size_t(INT_MAX), "pointer delta out of range: %zu", delta); 459 return static_cast<int>(delta); 460 } 461 462 // 463 // ANSI C++ does not allow casting from one pointer type to a function pointer 464 // directly without at best a warning. This macro accomplishes it silently 465 // In every case that is present at this point the value be cast is a pointer 466 // to a C linkage function. In some case the type used for the cast reflects 467 // that linkage and a picky compiler would not complain. In other cases because 468 // there is no convenient place to place a typedef with extern C linkage (i.e 469 // a platform dependent header file) it doesn't. At this point no compiler seems 470 // picky enough to catch these instances (which are few). It is possible that 471 // using templates could fix these for all cases. This use of templates is likely 472 // so far from the middle of the road that it is likely to be problematic in 473 // many C++ compilers. 474 // 475 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value)) 476 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((uintptr_t)(func_ptr))) 477 478 // Need the correct linkage to call qsort without warnings 479 extern "C" { 480 typedef int (*_sort_Fn)(const void *, const void *); 481 } 482 483 // Additional Java basic types 484 485 typedef uint8_t jubyte; 486 typedef uint16_t jushort; 487 typedef uint32_t juint; 488 typedef uint64_t julong; 489 490 // Unsigned byte types for os and stream.hpp 491 492 // Unsigned one, two, four and eight byte quantities used for describing 493 // the .class file format. See JVM book chapter 4. 494 495 typedef jubyte u1; 496 typedef jushort u2; 497 typedef juint u4; 498 typedef julong u8; 499 500 const jubyte max_jubyte = (jubyte)-1; // 0xFF largest jubyte 501 const jushort max_jushort = (jushort)-1; // 0xFFFF largest jushort 502 const juint max_juint = (juint)-1; // 0xFFFFFFFF largest juint 503 const julong max_julong = (julong)-1; // 0xFF....FF largest julong 504 505 typedef jbyte s1; 506 typedef jshort s2; 507 typedef jint s4; 508 typedef jlong s8; 509 510 const jbyte min_jbyte = -(1 << 7); // smallest jbyte 511 const jbyte max_jbyte = (1 << 7) - 1; // largest jbyte 512 const jshort min_jshort = -(1 << 15); // smallest jshort 513 const jshort max_jshort = (1 << 15) - 1; // largest jshort 514 515 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint 516 const jint max_jint = (juint)min_jint - 1; // 0x7FFFFFFF == largest jint 517 518 const jint min_jintFloat = (jint)(0x00000001); 519 const jfloat min_jfloat = jfloat_cast(min_jintFloat); 520 const jint max_jintFloat = (jint)(0x7f7fffff); 521 const jfloat max_jfloat = jfloat_cast(max_jintFloat); 522 523 const jshort max_jfloat16 = 31743; 524 const jshort min_jfloat16 = 1; 525 const jshort one_jfloat16 = 15360; 526 const jshort pos_inf_jfloat16 = 31744; 527 const jshort neg_inf_jfloat16 = -1024; 528 // A named constant for the integral representation of a Java null. 529 const intptr_t NULL_WORD = 0; 530 531 //---------------------------------------------------------------------------------------------------- 532 // JVM spec restrictions 533 534 const int max_method_code_size = 64*K - 1; // JVM spec, 2nd ed. section 4.8.1 (p.134) 535 536 //---------------------------------------------------------------------------------------------------- 537 // old CDS options 538 extern bool RequireSharedSpaces; 539 extern "C" { 540 // Make sure UseSharedSpaces is accessible to the serviceability agent. 541 extern JNIEXPORT jboolean UseSharedSpaces; 542 } 543 544 //---------------------------------------------------------------------------------------------------- 545 // Object alignment, in units of HeapWords. 546 // 547 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and 548 // reference fields can be naturally aligned. 549 550 extern int MinObjAlignment; 551 extern int MinObjAlignmentInBytes; 552 extern int MinObjAlignmentInBytesMask; 553 554 extern int LogMinObjAlignment; 555 extern int LogMinObjAlignmentInBytes; 556 557 // Maximal size of heap where unscaled compression can be used. Also upper bound 558 // for heap placement: 4GB. 559 const uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1); 560 // Maximal size of heap where compressed oops can be used. Also upper bound for heap 561 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes. 562 extern uint64_t OopEncodingHeapMax; 563 564 // Machine dependent stuff 565 566 #include CPU_HEADER(globalDefinitions) 567 568 // The maximum size of the code cache. Can be overridden by targets. 569 #ifndef CODE_CACHE_SIZE_LIMIT 570 #define CODE_CACHE_SIZE_LIMIT (2*G) 571 #endif 572 573 // Allow targets to reduce the default size of the code cache. 574 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT 575 576 // To assure the IRIW property on processors that are not multiple copy 577 // atomic, sync instructions must be issued between volatile reads to 578 // assure their ordering, instead of after volatile stores. 579 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models" 580 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge) 581 #ifdef CPU_MULTI_COPY_ATOMIC 582 // Not needed. 583 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false; 584 #else 585 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment. 586 // Final decision is subject to JEP 188: Java Memory Model Update. 587 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false); 588 #endif 589 590 // The expected size in bytes of a cache line. 591 #ifndef DEFAULT_CACHE_LINE_SIZE 592 #error "Platform should define DEFAULT_CACHE_LINE_SIZE" 593 #endif 594 595 // The default padding size for data structures to avoid false sharing. 596 #ifndef DEFAULT_PADDING_SIZE 597 #error "Platform should define DEFAULT_PADDING_SIZE" 598 #endif 599 600 601 //---------------------------------------------------------------------------------------------------- 602 // Prototyping 603 // "Code Missing Here" macro, un-define when integrating back from prototyping stage and break 604 // compilation on purpose (i.e. "forget me not") 605 #define PROTOTYPE 606 #ifdef PROTOTYPE 607 #define CMH(m) 608 #endif 609 610 //---------------------------------------------------------------------------------------------------- 611 // Miscellaneous 612 613 // 6302670 Eliminate Hotspot __fabsf dependency 614 // All fabs() callers should call this function instead, which will implicitly 615 // convert the operand to double, avoiding a dependency on __fabsf which 616 // doesn't exist in early versions of Solaris 8. 617 inline double fabsd(double value) { 618 return fabs(value); 619 } 620 621 // Returns numerator/denominator as percentage value from 0 to 100. If denominator 622 // is zero, return 0.0. 623 template<typename T> 624 inline double percent_of(T numerator, T denominator) { 625 return denominator != 0 ? (double)numerator / (double)denominator * 100.0 : 0.0; 626 } 627 628 //---------------------------------------------------------------------------------------------------- 629 // Special casts 630 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern 631 typedef union { 632 jfloat f; 633 jint i; 634 } FloatIntConv; 635 636 typedef union { 637 jdouble d; 638 jlong l; 639 julong ul; 640 } DoubleLongConv; 641 642 inline jint jint_cast (jfloat x) { return ((FloatIntConv*)&x)->i; } 643 inline jfloat jfloat_cast (jint x) { return ((FloatIntConv*)&x)->f; } 644 645 inline jlong jlong_cast (jdouble x) { return ((DoubleLongConv*)&x)->l; } 646 inline julong julong_cast (jdouble x) { return ((DoubleLongConv*)&x)->ul; } 647 inline jdouble jdouble_cast (jlong x) { return ((DoubleLongConv*)&x)->d; } 648 649 inline jint low (jlong value) { return jint(value); } 650 inline jint high(jlong value) { return jint(value >> 32); } 651 652 // the fancy casts are a hopefully portable way 653 // to do unsigned 32 to 64 bit type conversion 654 inline void set_low (jlong* value, jint low ) { *value &= (jlong)0xffffffff << 32; 655 *value |= (jlong)(julong)(juint)low; } 656 657 inline void set_high(jlong* value, jint high) { *value &= (jlong)(julong)(juint)0xffffffff; 658 *value |= (jlong)high << 32; } 659 660 inline jlong jlong_from(jint h, jint l) { 661 jlong result = 0; // initialization to avoid warning 662 set_high(&result, h); 663 set_low(&result, l); 664 return result; 665 } 666 667 union jlong_accessor { 668 jint words[2]; 669 jlong long_value; 670 }; 671 672 void basic_types_init(); // cannot define here; uses assert 673 674 675 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java 676 enum BasicType : u1 { 677 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS. 678 T_BOOLEAN = JVM_T_BOOLEAN, 679 T_CHAR = JVM_T_CHAR, 680 T_FLOAT = JVM_T_FLOAT, 681 T_DOUBLE = JVM_T_DOUBLE, 682 T_BYTE = JVM_T_BYTE, 683 T_SHORT = JVM_T_SHORT, 684 T_INT = JVM_T_INT, 685 T_LONG = JVM_T_LONG, 686 // The remaining values are not part of any standard. 687 // T_OBJECT and T_VOID denote two more semantic choices 688 // for method return values. 689 // T_OBJECT and T_ARRAY describe signature syntax. 690 // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe 691 // internal references within the JVM as if they were Java 692 // types in their own right. 693 T_OBJECT = 12, 694 T_ARRAY = 13, 695 T_FLAT_ELEMENT = 14, // Not a true BasicType, only use in headers of flat arrays 696 T_VOID = 15, 697 T_ADDRESS = 16, 698 T_NARROWOOP = 17, 699 T_METADATA = 18, 700 T_NARROWKLASS = 19, 701 T_CONFLICT = 20, // for stack value type with conflicting contents 702 T_ILLEGAL = 99 703 }; 704 705 #define SIGNATURE_TYPES_DO(F, N) \ 706 F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N) \ 707 F(JVM_SIGNATURE_CHAR, T_CHAR, N) \ 708 F(JVM_SIGNATURE_FLOAT, T_FLOAT, N) \ 709 F(JVM_SIGNATURE_DOUBLE, T_DOUBLE, N) \ 710 F(JVM_SIGNATURE_BYTE, T_BYTE, N) \ 711 F(JVM_SIGNATURE_SHORT, T_SHORT, N) \ 712 F(JVM_SIGNATURE_INT, T_INT, N) \ 713 F(JVM_SIGNATURE_LONG, T_LONG, N) \ 714 F(JVM_SIGNATURE_CLASS, T_OBJECT, N) \ 715 F(JVM_SIGNATURE_ARRAY, T_ARRAY, N) \ 716 F(JVM_SIGNATURE_FLAT_ELEMENT, T_FLAT_ELEMENT, N) \ 717 F(JVM_SIGNATURE_VOID, T_VOID, N) \ 718 /*end*/ 719 720 inline bool is_java_type(BasicType t) { 721 return T_BOOLEAN <= t && t <= T_VOID; 722 } 723 724 inline bool is_java_primitive(BasicType t) { 725 return T_BOOLEAN <= t && t <= T_LONG; 726 } 727 728 inline bool is_subword_type(BasicType t) { 729 // these guys are processed exactly like T_INT in calling sequences: 730 return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT); 731 } 732 733 inline bool is_signed_subword_type(BasicType t) { 734 return (t == T_BYTE || t == T_SHORT); 735 } 736 737 inline bool is_unsigned_subword_type(BasicType t) { 738 return (t == T_BOOLEAN || t == T_CHAR); 739 } 740 741 inline bool is_double_word_type(BasicType t) { 742 return (t == T_DOUBLE || t == T_LONG); 743 } 744 745 inline bool is_reference_type(BasicType t, bool include_narrow_oop = false) { 746 return (t == T_OBJECT || t == T_ARRAY || t == T_FLAT_ELEMENT || (include_narrow_oop && t == T_NARROWOOP)); 747 } 748 749 inline bool is_integral_type(BasicType t) { 750 return is_subword_type(t) || t == T_INT || t == T_LONG; 751 } 752 753 inline bool is_non_subword_integral_type(BasicType t) { 754 return t == T_INT || t == T_LONG; 755 } 756 757 inline bool is_floating_point_type(BasicType t) { 758 return (t == T_FLOAT || t == T_DOUBLE); 759 } 760 761 extern char type2char_tab[T_CONFLICT+1]; // Map a BasicType to a jchar 762 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; } 763 extern int type2size[T_CONFLICT+1]; // Map BasicType to result stack elements 764 extern const char* type2name_tab[T_CONFLICT+1]; // Map a BasicType to a char* 765 extern BasicType name2type(const char* name); 766 767 const char* type2name(BasicType t); 768 769 inline jlong max_signed_integer(BasicType bt) { 770 if (bt == T_INT) { 771 return max_jint; 772 } 773 assert(bt == T_LONG, "unsupported"); 774 return max_jlong; 775 } 776 777 inline jlong min_signed_integer(BasicType bt) { 778 if (bt == T_INT) { 779 return min_jint; 780 } 781 assert(bt == T_LONG, "unsupported"); 782 return min_jlong; 783 } 784 785 inline uint bits_per_java_integer(BasicType bt) { 786 if (bt == T_INT) { 787 return BitsPerJavaInteger; 788 } 789 assert(bt == T_LONG, "int or long only"); 790 return BitsPerJavaLong; 791 } 792 793 // Auxiliary math routines 794 // least common multiple 795 extern size_t lcm(size_t a, size_t b); 796 797 798 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java 799 enum BasicTypeSize { 800 T_BOOLEAN_size = 1, 801 T_CHAR_size = 1, 802 T_FLOAT_size = 1, 803 T_DOUBLE_size = 2, 804 T_BYTE_size = 1, 805 T_SHORT_size = 1, 806 T_INT_size = 1, 807 T_LONG_size = 2, 808 T_OBJECT_size = 1, 809 T_ARRAY_size = 1, 810 T_NARROWOOP_size = 1, 811 T_NARROWKLASS_size = 1, 812 T_VOID_size = 0, 813 T_FLAT_ELEMENT_size = 1 814 }; 815 816 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc. 817 inline int parameter_type_word_count(BasicType t) { 818 if (is_double_word_type(t)) return 2; 819 assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please"); 820 assert(type2size[t] == 1, "must be"); 821 return 1; 822 } 823 824 // maps a BasicType to its instance field storage type: 825 // all sub-word integral types are widened to T_INT 826 extern BasicType type2field[T_CONFLICT+1]; 827 extern BasicType type2wfield[T_CONFLICT+1]; 828 829 830 // size in bytes 831 enum ArrayElementSize { 832 T_BOOLEAN_aelem_bytes = 1, 833 T_CHAR_aelem_bytes = 2, 834 T_FLOAT_aelem_bytes = 4, 835 T_DOUBLE_aelem_bytes = 8, 836 T_BYTE_aelem_bytes = 1, 837 T_SHORT_aelem_bytes = 2, 838 T_INT_aelem_bytes = 4, 839 T_LONG_aelem_bytes = 8, 840 #ifdef _LP64 841 T_OBJECT_aelem_bytes = 8, 842 T_ARRAY_aelem_bytes = 8, 843 T_FLAT_ELEMENT_aelem_bytes = 8, 844 #else 845 T_OBJECT_aelem_bytes = 4, 846 T_ARRAY_aelem_bytes = 4, 847 T_FLAT_ELEMENT_aelem_bytes = 4, 848 #endif 849 T_NARROWOOP_aelem_bytes = 4, 850 T_NARROWKLASS_aelem_bytes = 4, 851 T_VOID_aelem_bytes = 0 852 }; 853 854 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element 855 #ifdef ASSERT 856 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts 857 #else 858 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; } 859 #endif 860 861 inline bool same_type_or_subword_size(BasicType t1, BasicType t2) { 862 return (t1 == t2) || (is_subword_type(t1) && type2aelembytes(t1) == type2aelembytes(t2)); 863 } 864 865 // JavaValue serves as a container for arbitrary Java values. 866 867 class JavaValue { 868 869 public: 870 typedef union JavaCallValue { 871 jfloat f; 872 jdouble d; 873 jint i; 874 jlong l; 875 jobject h; 876 oopDesc* o; 877 } JavaCallValue; 878 879 private: 880 BasicType _type; 881 JavaCallValue _value; 882 883 public: 884 JavaValue(BasicType t = T_ILLEGAL) { _type = t; } 885 886 JavaValue(jfloat value) { 887 _type = T_FLOAT; 888 _value.f = value; 889 } 890 891 JavaValue(jdouble value) { 892 _type = T_DOUBLE; 893 _value.d = value; 894 } 895 896 jfloat get_jfloat() const { return _value.f; } 897 jdouble get_jdouble() const { return _value.d; } 898 jint get_jint() const { return _value.i; } 899 jlong get_jlong() const { return _value.l; } 900 jobject get_jobject() const { return _value.h; } 901 oopDesc* get_oop() const { return _value.o; } 902 JavaCallValue* get_value_addr() { return &_value; } 903 BasicType get_type() const { return _type; } 904 905 void set_jfloat(jfloat f) { _value.f = f;} 906 void set_jdouble(jdouble d) { _value.d = d;} 907 void set_jint(jint i) { _value.i = i;} 908 void set_jshort(jshort i) { _value.i = i;} 909 void set_jlong(jlong l) { _value.l = l;} 910 void set_jobject(jobject h) { _value.h = h;} 911 void set_oop(oopDesc* o) { _value.o = o;} 912 void set_type(BasicType t) { _type = t; } 913 914 jboolean get_jboolean() const { return (jboolean) (_value.i);} 915 jbyte get_jbyte() const { return (jbyte) (_value.i);} 916 jchar get_jchar() const { return (jchar) (_value.i);} 917 jshort get_jshort() const { return (jshort) (_value.i);} 918 919 }; 920 921 922 // TosState describes the top-of-stack state before and after the execution of 923 // a bytecode or method. The top-of-stack value may be cached in one or more CPU 924 // registers. The TosState corresponds to the 'machine representation' of this cached 925 // value. There's 4 states corresponding to the JAVA types int, long, float & double 926 // as well as a 5th state in case the top-of-stack value is actually on the top 927 // of stack (in memory) and thus not cached. The atos state corresponds to the itos 928 // state when it comes to machine representation but is used separately for (oop) 929 // type specific operations (e.g. verification code). 930 931 enum TosState { // describes the tos cache contents 932 btos = 0, // byte, bool tos cached 933 ztos = 1, // byte, bool tos cached 934 ctos = 2, // char tos cached 935 stos = 3, // short tos cached 936 itos = 4, // int tos cached 937 ltos = 5, // long tos cached 938 ftos = 6, // float tos cached 939 dtos = 7, // double tos cached 940 atos = 8, // object cached 941 vtos = 9, // tos not cached, 942 number_of_states, 943 ilgl // illegal state: should not occur 944 }; 945 946 947 inline TosState as_TosState(BasicType type) { 948 switch (type) { 949 case T_BYTE : return btos; 950 case T_BOOLEAN: return ztos; 951 case T_CHAR : return ctos; 952 case T_SHORT : return stos; 953 case T_INT : return itos; 954 case T_LONG : return ltos; 955 case T_FLOAT : return ftos; 956 case T_DOUBLE : return dtos; 957 case T_VOID : return vtos; 958 case T_ARRAY : // fall through 959 case T_OBJECT : return atos; 960 default : return ilgl; 961 } 962 } 963 964 inline BasicType as_BasicType(TosState state) { 965 switch (state) { 966 case btos : return T_BYTE; 967 case ztos : return T_BOOLEAN; 968 case ctos : return T_CHAR; 969 case stos : return T_SHORT; 970 case itos : return T_INT; 971 case ltos : return T_LONG; 972 case ftos : return T_FLOAT; 973 case dtos : return T_DOUBLE; 974 case atos : return T_OBJECT; 975 case vtos : return T_VOID; 976 default : return T_ILLEGAL; 977 } 978 } 979 980 981 // Helper function to convert BasicType info into TosState 982 // Note: Cannot define here as it uses global constant at the time being. 983 TosState as_TosState(BasicType type); 984 985 986 // JavaThreadState keeps track of which part of the code a thread is executing in. This 987 // information is needed by the safepoint code. 988 // 989 // There are 4 essential states: 990 // 991 // _thread_new : Just started, but not executed init. code yet (most likely still in OS init code) 992 // _thread_in_native : In native code. This is a safepoint region, since all oops will be in jobject handles 993 // _thread_in_vm : Executing in the vm 994 // _thread_in_Java : Executing either interpreted or compiled Java code (or could be in a stub) 995 // 996 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in 997 // a transition from one state to another. These extra states makes it possible for the safepoint code to 998 // handle certain thread_states without having to suspend the thread - making the safepoint code faster. 999 // 1000 // Given a state, the xxxx_trans state can always be found by adding 1. 1001 // 1002 enum JavaThreadState { 1003 _thread_uninitialized = 0, // should never happen (missing initialization) 1004 _thread_new = 2, // just starting up, i.e., in process of being initialized 1005 _thread_new_trans = 3, // corresponding transition state (not used, included for completeness) 1006 _thread_in_native = 4, // running in native code 1007 _thread_in_native_trans = 5, // corresponding transition state 1008 _thread_in_vm = 6, // running in VM 1009 _thread_in_vm_trans = 7, // corresponding transition state 1010 _thread_in_Java = 8, // running in Java or in stub code 1011 _thread_in_Java_trans = 9, // corresponding transition state (not used, included for completeness) 1012 _thread_blocked = 10, // blocked in vm 1013 _thread_blocked_trans = 11, // corresponding transition state 1014 _thread_max_state = 12 // maximum thread state+1 - used for statistics allocation 1015 }; 1016 1017 enum LockingMode { 1018 // Use only heavy monitors for locking 1019 LM_MONITOR = 0, 1020 // Legacy stack-locking, with monitors as 2nd tier 1021 LM_LEGACY = 1, 1022 // New lightweight locking, with monitors as 2nd tier 1023 LM_LIGHTWEIGHT = 2 1024 }; 1025 1026 //---------------------------------------------------------------------------------------------------- 1027 // Special constants for debugging 1028 1029 const jint badInt = -3; // generic "bad int" value 1030 const intptr_t badAddressVal = -2; // generic "bad address" value 1031 const intptr_t badOopVal = -1; // generic "bad oop" value 1032 const intptr_t badHeapOopVal = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC 1033 const int badStackSegVal = 0xCA; // value used to zap stack segments 1034 const int badHandleValue = 0xBC; // value used to zap vm handle area 1035 const int badResourceValue = 0xAB; // value used to zap resource area 1036 const int freeBlockPad = 0xBA; // value used to pad freed blocks. 1037 const int uninitBlockPad = 0xF1; // value used to zap newly malloc'd blocks. 1038 const juint uninitMetaWordVal = 0xf7f7f7f7; // value used to zap newly allocated metachunk 1039 const jubyte heapPaddingByteVal = 0xBD; // value used to zap object padding in the heap 1040 const juint badHeapWordVal = 0xBAADBABE; // value used to zap heap after GC 1041 const int badCodeHeapNewVal = 0xCC; // value used to zap Code heap at allocation 1042 const int badCodeHeapFreeVal = 0xDD; // value used to zap Code heap at deallocation 1043 const intptr_t badDispHeaderDeopt = 0xDE0BD000; // value to fill unused displaced header during deoptimization 1044 const intptr_t badDispHeaderOSR = 0xDEAD05A0; // value to fill unused displaced header during OSR 1045 1046 // (These must be implemented as #defines because C++ compilers are 1047 // not obligated to inline non-integral constants!) 1048 #define badAddress ((address)::badAddressVal) 1049 #define badHeapWord (::badHeapWordVal) 1050 1051 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit) 1052 const uint TASKQUEUE_SIZE = (NOT_LP64(1<<14) LP64_ONLY(1<<17)); 1053 1054 //---------------------------------------------------------------------------------------------------- 1055 // Utility functions for bitfield manipulations 1056 1057 const intptr_t AllBits = ~0; // all bits set in a word 1058 const intptr_t NoBits = 0; // no bits set in a word 1059 const jlong NoLongBits = 0; // no bits set in a long 1060 const intptr_t OneBit = 1; // only right_most bit set in a word 1061 1062 // get a word with the n.th or the right-most or left-most n bits set 1063 // (note: #define used only so that they can be used in enum constant definitions) 1064 #define nth_bit(n) (((n) >= BitsPerWord) ? 0 : (OneBit << (n))) 1065 #define right_n_bits(n) (nth_bit(n) - 1) 1066 1067 // bit-operations using a mask m 1068 inline void set_bits (intptr_t& x, intptr_t m) { x |= m; } 1069 inline void clear_bits (intptr_t& x, intptr_t m) { x &= ~m; } 1070 inline intptr_t mask_bits (intptr_t x, intptr_t m) { return x & m; } 1071 inline jlong mask_long_bits (jlong x, jlong m) { return x & m; } 1072 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; } 1073 1074 // bit-operations using the n.th bit 1075 inline void set_nth_bit(intptr_t& x, int n) { set_bits (x, nth_bit(n)); } 1076 inline void clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); } 1077 inline bool is_set_nth_bit(intptr_t x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; } 1078 1079 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!) 1080 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) { 1081 return mask_bits(x >> start_bit_no, right_n_bits(field_length)); 1082 } 1083 1084 1085 //---------------------------------------------------------------------------------------------------- 1086 // Utility functions for integers 1087 1088 // Avoid use of global min/max macros which may cause unwanted double 1089 // evaluation of arguments. 1090 #ifdef max 1091 #undef max 1092 #endif 1093 1094 #ifdef min 1095 #undef min 1096 #endif 1097 1098 // It is necessary to use templates here. Having normal overloaded 1099 // functions does not work because it is necessary to provide both 32- 1100 // and 64-bit overloaded functions, which does not work, and having 1101 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L) 1102 // will be even more error-prone than macros. 1103 template<class T> constexpr T MAX2(T a, T b) { return (a > b) ? a : b; } 1104 template<class T> constexpr T MIN2(T a, T b) { return (a < b) ? a : b; } 1105 template<class T> constexpr T MAX3(T a, T b, T c) { return MAX2(MAX2(a, b), c); } 1106 template<class T> constexpr T MIN3(T a, T b, T c) { return MIN2(MIN2(a, b), c); } 1107 template<class T> constexpr T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); } 1108 template<class T> constexpr T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); } 1109 1110 #define ABS(x) asserted_abs(x, __FILE__, __LINE__) 1111 1112 template<class T> inline T asserted_abs(T x, const char* file, int line) { 1113 bool valid_arg = !(std::is_integral<T>::value && x == std::numeric_limits<T>::min()); 1114 #ifdef ASSERT 1115 if (!valid_arg) { 1116 report_vm_error(file, line, "ABS: argument should not allow overflow"); 1117 } 1118 #endif 1119 // Prevent exposure to UB by checking valid_arg here as well. 1120 return (x < 0 && valid_arg) ? -x : x; 1121 } 1122 1123 // Return the given value clamped to the range [min ... max] 1124 template<typename T> 1125 inline T clamp(T value, T min, T max) { 1126 assert(min <= max, "must be"); 1127 return MIN2(MAX2(value, min), max); 1128 } 1129 1130 inline bool is_odd (intx x) { return x & 1; } 1131 inline bool is_even(intx x) { return !is_odd(x); } 1132 1133 // abs methods which cannot overflow and so are well-defined across 1134 // the entire domain of integer types. 1135 static inline unsigned int uabs(unsigned int n) { 1136 union { 1137 unsigned int result; 1138 int value; 1139 }; 1140 result = n; 1141 if (value < 0) result = 0-result; 1142 return result; 1143 } 1144 static inline julong uabs(julong n) { 1145 union { 1146 julong result; 1147 jlong value; 1148 }; 1149 result = n; 1150 if (value < 0) result = 0-result; 1151 return result; 1152 } 1153 static inline julong uabs(jlong n) { return uabs((julong)n); } 1154 static inline unsigned int uabs(int n) { return uabs((unsigned int)n); } 1155 1156 // "to" should be greater than "from." 1157 inline size_t byte_size(void* from, void* to) { 1158 return pointer_delta(to, from, sizeof(char)); 1159 } 1160 1161 // Pack and extract shorts to/from ints: 1162 1163 inline u2 extract_low_short_from_int(u4 x) { 1164 return u2(x & 0xffff); 1165 } 1166 1167 inline u2 extract_high_short_from_int(u4 x) { 1168 return u2((x >> 16) & 0xffff); 1169 } 1170 1171 inline int build_int_from_shorts( u2 low, u2 high ) { 1172 return ((int)((unsigned int)high << 16) | (unsigned int)low); 1173 } 1174 1175 // swap a & b 1176 template<class T> static void swap(T& a, T& b) { 1177 T tmp = a; 1178 a = b; 1179 b = tmp; 1180 } 1181 1182 // array_size_impl is a function that takes a reference to T[N] and 1183 // returns a reference to char[N]. It is not ODR-used, so not defined. 1184 template<typename T, size_t N> char (&array_size_impl(T (&)[N]))[N]; 1185 1186 #define ARRAY_SIZE(array) sizeof(array_size_impl(array)) 1187 1188 //---------------------------------------------------------------------------------------------------- 1189 // Sum and product which can never overflow: they wrap, just like the 1190 // Java operations. Note that we don't intend these to be used for 1191 // general-purpose arithmetic: their purpose is to emulate Java 1192 // operations. 1193 1194 // The goal of this code to avoid undefined or implementation-defined 1195 // behavior. The use of an lvalue to reference cast is explicitly 1196 // permitted by Lvalues and rvalues [basic.lval]. [Section 3.10 Para 1197 // 15 in C++03] 1198 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE) \ 1199 inline TYPE NAME (TYPE in1, TYPE in2) { \ 1200 UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \ 1201 ures OP ## = static_cast<UNSIGNED_TYPE>(in2); \ 1202 return reinterpret_cast<TYPE&>(ures); \ 1203 } 1204 1205 JAVA_INTEGER_OP(+, java_add, jint, juint) 1206 JAVA_INTEGER_OP(-, java_subtract, jint, juint) 1207 JAVA_INTEGER_OP(*, java_multiply, jint, juint) 1208 JAVA_INTEGER_OP(+, java_add, jlong, julong) 1209 JAVA_INTEGER_OP(-, java_subtract, jlong, julong) 1210 JAVA_INTEGER_OP(*, java_multiply, jlong, julong) 1211 1212 inline jint java_negate(jint v) { return java_subtract((jint) 0, v); } 1213 inline jlong java_negate(jlong v) { return java_subtract((jlong)0, v); } 1214 1215 #undef JAVA_INTEGER_OP 1216 1217 // Provide integer shift operations with Java semantics. No overflow 1218 // issues - left shifts simply discard shifted out bits. No undefined 1219 // behavior for large or negative shift quantities; instead the actual 1220 // shift distance is the argument modulo the lhs value's size in bits. 1221 // No undefined or implementation defined behavior for shifting negative 1222 // values; left shift discards bits, right shift sign extends. We use 1223 // the same safe conversion technique as above for java_add and friends. 1224 #define JAVA_INTEGER_SHIFT_OP(OP, NAME, TYPE, XTYPE) \ 1225 inline TYPE NAME (TYPE lhs, jint rhs) { \ 1226 const uint rhs_mask = (sizeof(TYPE) * 8) - 1; \ 1227 STATIC_ASSERT(rhs_mask == 31 || rhs_mask == 63); \ 1228 XTYPE xres = static_cast<XTYPE>(lhs); \ 1229 xres OP ## = (rhs & rhs_mask); \ 1230 return reinterpret_cast<TYPE&>(xres); \ 1231 } 1232 1233 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jint, juint) 1234 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jlong, julong) 1235 1236 // For signed shift right, assume C++ implementation >> sign extends. 1237 // 1238 // C++14 5.8/3: In the description of "E1 >> E2" it says "If E1 has a signed type 1239 // and a negative value, the resulting value is implementation-defined." 1240 // 1241 // However, C++20 7.6.7/3 further defines integral arithmetic, as part of 1242 // requiring two's-complement behavior. 1243 // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0907r3.html 1244 // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1236r1.html 1245 // The corresponding C++20 text is "Right-shift on signed integral types is an 1246 // arithmetic right shift, which performs sign-extension." 1247 // 1248 // As discussed in the two's complement proposal, all known modern C++ compilers 1249 // already behave that way. And it is unlikely any would go off and do something 1250 // different now, with C++20 tightening things up. 1251 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jint, jint) 1252 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jlong, jlong) 1253 // For >>> use C++ unsigned >>. 1254 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jint, juint) 1255 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jlong, julong) 1256 1257 #undef JAVA_INTEGER_SHIFT_OP 1258 1259 //---------------------------------------------------------------------------------------------------- 1260 // The goal of this code is to provide saturating operations for int/uint. 1261 // Checks overflow conditions and saturates the result to min_jint/max_jint. 1262 #define SATURATED_INTEGER_OP(OP, NAME, TYPE1, TYPE2) \ 1263 inline int NAME (TYPE1 in1, TYPE2 in2) { \ 1264 jlong res = static_cast<jlong>(in1); \ 1265 res OP ## = static_cast<jlong>(in2); \ 1266 if (res > max_jint) { \ 1267 res = max_jint; \ 1268 } else if (res < min_jint) { \ 1269 res = min_jint; \ 1270 } \ 1271 return static_cast<int>(res); \ 1272 } 1273 1274 SATURATED_INTEGER_OP(+, saturated_add, int, int) 1275 SATURATED_INTEGER_OP(+, saturated_add, int, uint) 1276 SATURATED_INTEGER_OP(+, saturated_add, uint, int) 1277 SATURATED_INTEGER_OP(+, saturated_add, uint, uint) 1278 1279 #undef SATURATED_INTEGER_OP 1280 1281 // Taken from rom section 8-2 of Henry S. Warren, Jr., Hacker's Delight (2nd ed.) (Addison Wesley, 2013), 173-174. 1282 inline uint64_t multiply_high_unsigned(const uint64_t x, const uint64_t y) { 1283 const uint64_t x1 = x >> 32u; 1284 const uint64_t x2 = x & 0xFFFFFFFF; 1285 const uint64_t y1 = y >> 32u; 1286 const uint64_t y2 = y & 0xFFFFFFFF; 1287 const uint64_t z2 = x2 * y2; 1288 const uint64_t t = x1 * y2 + (z2 >> 32u); 1289 uint64_t z1 = t & 0xFFFFFFFF; 1290 const uint64_t z0 = t >> 32u; 1291 z1 += x2 * y1; 1292 1293 return x1 * y1 + z0 + (z1 >> 32u); 1294 } 1295 1296 // Taken from java.lang.Math::multiplyHigh which uses the technique from section 8-2 of Henry S. Warren, Jr., 1297 // Hacker's Delight (2nd ed.) (Addison Wesley, 2013), 173-174 but adapted for signed longs. 1298 inline int64_t multiply_high_signed(const int64_t x, const int64_t y) { 1299 const jlong x1 = java_shift_right((jlong)x, 32); 1300 const jlong x2 = x & 0xFFFFFFFF; 1301 const jlong y1 = java_shift_right((jlong)y, 32); 1302 const jlong y2 = y & 0xFFFFFFFF; 1303 1304 const uint64_t z2 = (uint64_t)x2 * y2; 1305 const int64_t t = x1 * y2 + (z2 >> 32u); // Unsigned shift 1306 int64_t z1 = t & 0xFFFFFFFF; 1307 const int64_t z0 = java_shift_right((jlong)t, 32); 1308 z1 += x2 * y1; 1309 1310 return x1 * y1 + z0 + java_shift_right((jlong)z1, 32); 1311 } 1312 1313 // Dereference vptr 1314 // All C++ compilers that we know of have the vtbl pointer in the first 1315 // word. If there are exceptions, this function needs to be made compiler 1316 // specific. 1317 static inline void* dereference_vptr(const void* addr) { 1318 return *(void**)addr; 1319 } 1320 1321 //---------------------------------------------------------------------------------------------------- 1322 // String type aliases used by command line flag declarations and 1323 // processing utilities. 1324 1325 typedef const char* ccstr; 1326 typedef const char* ccstrlist; // represents string arguments which accumulate 1327 1328 //---------------------------------------------------------------------------------------------------- 1329 // Default hash/equals functions used by ResourceHashtable 1330 1331 template<typename K> unsigned primitive_hash(const K& k) { 1332 unsigned hash = (unsigned)((uintptr_t)k); 1333 return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs 1334 } 1335 1336 template<typename K> bool primitive_equals(const K& k0, const K& k1) { 1337 return k0 == k1; 1338 } 1339 1340 template<typename K> int primitive_compare(const K& k0, const K& k1) { 1341 return ((k0 < k1) ? -1 : (k0 == k1) ? 0 : 1); 1342 } 1343 1344 //---------------------------------------------------------------------------------------------------- 1345 1346 // Allow use of C++ thread_local when approved - see JDK-8282469. 1347 #define APPROVED_CPP_THREAD_LOCAL thread_local 1348 1349 // Converts any type T to a reference type. 1350 template<typename T> 1351 std::add_rvalue_reference_t<T> declval() noexcept; 1352 1353 // Quickly test to make sure IEEE-754 subnormal numbers are correctly 1354 // handled. 1355 bool IEEE_subnormal_handling_OK(); 1356 1357 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP