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/macros.hpp" 31 32 // Get constants like JVM_T_CHAR and JVM_SIGNATURE_INT, before pulling in <jvm.h>. 33 #include "classfile_constants.h" 34 35 #include COMPILER_HEADER(utilities/globalDefinitions) 36 37 #include <cstddef> 38 #include <cstdint> 39 #include <limits> 40 #include <type_traits> 41 42 class oopDesc; 43 44 // Defaults for macros that might be defined per compiler. 45 #ifndef NOINLINE 46 #define NOINLINE 47 #endif 48 #ifndef ALWAYSINLINE 49 #define ALWAYSINLINE inline 50 #endif 51 52 #ifndef ATTRIBUTE_ALIGNED 53 #define ATTRIBUTE_ALIGNED(x) alignas(x) 54 #endif 55 56 #ifndef ATTRIBUTE_FLATTEN 57 #define ATTRIBUTE_FLATTEN 58 #endif 59 60 // These are #defines to selectively turn on/off the Print(Opto)Assembly 61 // capabilities. Choices should be led by a tradeoff between 62 // code size and improved supportability. 63 // if PRINT_ASSEMBLY then PRINT_ABSTRACT_ASSEMBLY must be true as well 64 // to have a fallback in case hsdis is not available. 65 #if defined(PRODUCT) 66 #define SUPPORT_ABSTRACT_ASSEMBLY 67 #define SUPPORT_ASSEMBLY 68 #undef SUPPORT_OPTO_ASSEMBLY // Can't activate. In PRODUCT, many dump methods are missing. 69 #undef SUPPORT_DATA_STRUCTS // Of limited use. In PRODUCT, many print methods are empty. 70 #else 71 #define SUPPORT_ABSTRACT_ASSEMBLY 72 #define SUPPORT_ASSEMBLY 73 #define SUPPORT_OPTO_ASSEMBLY 74 #define SUPPORT_DATA_STRUCTS 75 #endif 76 #if defined(SUPPORT_ASSEMBLY) && !defined(SUPPORT_ABSTRACT_ASSEMBLY) 77 #define SUPPORT_ABSTRACT_ASSEMBLY 78 #endif 79 80 // This file holds all globally used constants & types, class (forward) 81 // declarations and a few frequently used utility functions. 82 83 // Declare the named class to be noncopyable. This macro must be followed by 84 // a semi-colon. The macro provides deleted declarations for the class's copy 85 // constructor and assignment operator. Because these operations are deleted, 86 // they cannot be defined and potential callers will fail to compile. 87 #define NONCOPYABLE(C) C(C const&) = delete; C& operator=(C const&) = delete /* next token must be ; */ 88 89 90 //---------------------------------------------------------------------------------------------------- 91 // Printf-style formatters for fixed- and variable-width types as pointers and 92 // integers. These are derived from the definitions in inttypes.h. If the platform 93 // doesn't provide appropriate definitions, they should be provided in 94 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp) 95 96 // Guide to the suffixes used in the format specifiers for integers: 97 // - print the decimal value: 745565 98 // _X - print as hexadecimal, without leading 0s: 0x12345 99 // _X_0 - print as hexadecimal, with leading 0s: 0x00012345 100 // _W(w) - prints w sized string with the given value right 101 // adjusted. Use -w to print left adjusted. 102 // _0 - print as hexadecimal, with leading 0s, without 0x prefix: 0012345 103 // 104 // Note that the PTR format specifiers print using 0x with leading zeros, 105 // just like the _X_0 version for integers. 106 107 // Format 8-bit quantities. 108 #define INT8_FORMAT_X_0 "0x%02" PRIx8 109 #define UINT8_FORMAT_X_0 "0x%02" PRIx8 110 111 // Format 16-bit quantities. 112 #define INT16_FORMAT_X_0 "0x%04" PRIx16 113 #define UINT16_FORMAT_X_0 "0x%04" PRIx16 114 115 // Format 32-bit quantities. 116 #define INT32_FORMAT "%" PRId32 117 #define INT32_FORMAT_X "0x%" PRIx32 118 #define INT32_FORMAT_X_0 "0x%08" PRIx32 119 #define INT32_FORMAT_W(width) "%" #width PRId32 120 #define UINT32_FORMAT "%" PRIu32 121 #define UINT32_FORMAT_X "0x%" PRIx32 122 #define UINT32_FORMAT_X_0 "0x%08" PRIx32 123 #define UINT32_FORMAT_W(width) "%" #width PRIu32 124 125 // Format 64-bit quantities. 126 #define INT64_FORMAT "%" PRId64 127 #define INT64_PLUS_FORMAT "%+" PRId64 128 #define INT64_FORMAT_X "0x%" PRIx64 129 #define INT64_FORMAT_X_0 "0x%016" PRIx64 130 #define INT64_FORMAT_W(width) "%" #width PRId64 131 #define UINT64_FORMAT "%" PRIu64 132 #define UINT64_FORMAT_X "0x%" PRIx64 133 #define UINT64_FORMAT_X_0 "0x%016" PRIx64 134 #define UINT64_FORMAT_W(width) "%" #width PRIu64 135 #define UINT64_FORMAT_0 "%016" PRIx64 136 137 // Format jlong, if necessary 138 #ifndef JLONG_FORMAT 139 #define JLONG_FORMAT INT64_FORMAT 140 #endif 141 #ifndef JLONG_FORMAT_W 142 #define JLONG_FORMAT_W(width) INT64_FORMAT_W(width) 143 #endif 144 #ifndef JULONG_FORMAT 145 #define JULONG_FORMAT UINT64_FORMAT 146 #endif 147 #ifndef JULONG_FORMAT_X 148 #define JULONG_FORMAT_X UINT64_FORMAT_X 149 #endif 150 151 // Format pointers and padded integral values which change size between 32- and 64-bit. 152 #ifdef _LP64 153 #define INTPTR_FORMAT "0x%016" PRIxPTR 154 #define PTR_FORMAT "0x%016" PRIxPTR 155 #define UINTX_FORMAT_X_0 "0x%016" PRIxPTR 156 #define SIZE_FORMAT_X_0 "0x%016" PRIxPTR 157 #else // !_LP64 158 #define INTPTR_FORMAT "0x%08" PRIxPTR 159 #define PTR_FORMAT "0x%08" PRIxPTR 160 #define UINTX_FORMAT_X_0 "0x%08" PRIxPTR 161 #define SIZE_FORMAT_X_0 "0x%08" PRIxPTR 162 #endif // _LP64 163 164 // Convert pointer to intptr_t, for use in printing pointers. 165 inline intptr_t p2i(const volatile void* p) { 166 return (intptr_t) p; 167 } 168 169 // Convert pointer to uintptr_t 170 inline uintptr_t p2u(const volatile void* p) { 171 return (uintptr_t) p; 172 } 173 174 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false") 175 176 //---------------------------------------------------------------------------------------------------- 177 // Forbid the use of various C library functions. 178 // Some of these have os:: replacements that should normally be used instead. 179 // Others are considered security concerns, with preferred alternatives. 180 181 FORBID_C_FUNCTION(void exit(int), "use os::exit"); 182 FORBID_C_FUNCTION(void _exit(int), "use os::exit"); 183 FORBID_C_FUNCTION(char* strerror(int), "use os::strerror"); 184 FORBID_C_FUNCTION(char* strtok(char*, const char*), "use strtok_r"); 185 FORBID_C_FUNCTION(int sprintf(char*, const char*, ...), "use os::snprintf"); 186 FORBID_C_FUNCTION(int vsprintf(char*, const char*, va_list), "use os::vsnprintf"); 187 FORBID_C_FUNCTION(int vsnprintf(char*, size_t, const char*, va_list), "use os::vsnprintf"); 188 189 // All of the following functions return raw C-heap pointers (sometimes as an option, e.g. realpath or getwd) 190 // or, in case of free(), take raw C-heap pointers. Don't use them unless you are really sure you must. 191 FORBID_C_FUNCTION(void* malloc(size_t size), "use os::malloc"); 192 FORBID_C_FUNCTION(void* calloc(size_t nmemb, size_t size), "use os::malloc and zero out manually"); 193 FORBID_C_FUNCTION(void free(void *ptr), "use os::free"); 194 FORBID_C_FUNCTION(void* realloc(void *ptr, size_t size), "use os::realloc"); 195 FORBID_C_FUNCTION(char* strdup(const char *s), "use os::strdup"); 196 FORBID_C_FUNCTION(char* strndup(const char *s, size_t n), "don't use"); 197 FORBID_C_FUNCTION(int posix_memalign(void **memptr, size_t alignment, size_t size), "don't use"); 198 FORBID_C_FUNCTION(void* aligned_alloc(size_t alignment, size_t size), "don't use"); 199 FORBID_C_FUNCTION(char* realpath(const char* path, char* resolved_path), "use os::realpath"); 200 FORBID_C_FUNCTION(char* get_current_dir_name(void), "use os::get_current_directory()"); 201 FORBID_C_FUNCTION(char* getwd(char *buf), "use os::get_current_directory()"); 202 FORBID_C_FUNCTION(wchar_t* wcsdup(const wchar_t *s), "don't use"); 203 FORBID_C_FUNCTION(void* reallocf(void *ptr, size_t size), "don't use"); 204 205 //---------------------------------------------------------------------------------------------------- 206 // Constants 207 208 const int LogBytesPerShort = 1; 209 const int LogBytesPerInt = 2; 210 #ifdef _LP64 211 constexpr int LogBytesPerWord = 3; 212 #else 213 constexpr int LogBytesPerWord = 2; 214 #endif 215 const int LogBytesPerLong = 3; 216 217 const int BytesPerShort = 1 << LogBytesPerShort; 218 const int BytesPerInt = 1 << LogBytesPerInt; 219 const int BytesPerWord = 1 << LogBytesPerWord; 220 const int BytesPerLong = 1 << LogBytesPerLong; 221 222 constexpr int LogBitsPerByte = 3; 223 const int LogBitsPerShort = LogBitsPerByte + LogBytesPerShort; 224 const int LogBitsPerInt = LogBitsPerByte + LogBytesPerInt; 225 constexpr int LogBitsPerWord = LogBitsPerByte + LogBytesPerWord; 226 const int LogBitsPerLong = LogBitsPerByte + LogBytesPerLong; 227 228 const int BitsPerByte = 1 << LogBitsPerByte; 229 const int BitsPerShort = 1 << LogBitsPerShort; 230 const int BitsPerInt = 1 << LogBitsPerInt; 231 constexpr int BitsPerWord = 1 << LogBitsPerWord; 232 const int BitsPerLong = 1 << LogBitsPerLong; 233 234 const int WordAlignmentMask = (1 << LogBytesPerWord) - 1; 235 const int LongAlignmentMask = (1 << LogBytesPerLong) - 1; 236 237 const int oopSize = sizeof(char*); // Full-width oop 238 extern int heapOopSize; // Oop within a java object 239 const int wordSize = sizeof(char*); 240 const int longSize = sizeof(jlong); 241 const int jintSize = sizeof(jint); 242 const int size_tSize = sizeof(size_t); 243 244 const int BytesPerOop = BytesPerWord; // Full-width oop 245 246 extern int LogBytesPerHeapOop; // Oop within a java object 247 extern int LogBitsPerHeapOop; 248 extern int BytesPerHeapOop; 249 extern int BitsPerHeapOop; 250 251 const int BitsPerJavaInteger = 32; 252 const int BitsPerJavaLong = 64; 253 const int BitsPerSize_t = size_tSize * BitsPerByte; 254 255 // Size of a char[] needed to represent a jint as a string in decimal. 256 const int jintAsStringSize = 12; 257 258 // An opaque type, so that HeapWord* can be a generic pointer into the heap. 259 // We require that object sizes be measured in units of heap words (e.g. 260 // pointer-sized values), so that given HeapWord* hw, 261 // hw += oop(hw)->foo(); 262 // works, where foo is a method (like size or scavenge) that returns the 263 // object size. 264 class HeapWordImpl; // Opaque, never defined. 265 typedef HeapWordImpl* HeapWord; 266 267 // Analogous opaque struct for metadata allocated from metaspaces. 268 class MetaWordImpl; // Opaque, never defined. 269 typedef MetaWordImpl* MetaWord; 270 271 // HeapWordSize must be 2^LogHeapWordSize. 272 const int HeapWordSize = sizeof(HeapWord); 273 #ifdef _LP64 274 const int LogHeapWordSize = 3; 275 #else 276 const int LogHeapWordSize = 2; 277 #endif 278 const int HeapWordsPerLong = BytesPerLong / HeapWordSize; 279 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize; 280 281 // The minimum number of native machine words necessary to contain "byte_size" 282 // bytes. 283 inline size_t heap_word_size(size_t byte_size) { 284 return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize; 285 } 286 287 inline jfloat jfloat_cast(jint x); 288 inline jdouble jdouble_cast(jlong x); 289 290 //------------------------------------------- 291 // Constant for jlong (standardized by C++11) 292 293 // Build a 64bit integer constant 294 #define CONST64(x) (x ## LL) 295 #define UCONST64(x) (x ## ULL) 296 297 const jlong min_jlong = CONST64(0x8000000000000000); 298 const jlong max_jlong = CONST64(0x7fffffffffffffff); 299 300 //------------------------------------------- 301 // Constant for jdouble 302 const jlong min_jlongDouble = CONST64(0x0000000000000001); 303 const jdouble min_jdouble = jdouble_cast(min_jlongDouble); 304 const jlong max_jlongDouble = CONST64(0x7fefffffffffffff); 305 const jdouble max_jdouble = jdouble_cast(max_jlongDouble); 306 307 const size_t K = 1024; 308 const size_t M = K*K; 309 const size_t G = M*K; 310 const size_t HWperKB = K / sizeof(HeapWord); 311 312 // Constants for converting from a base unit to milli-base units. For 313 // example from seconds to milliseconds and microseconds 314 315 const int MILLIUNITS = 1000; // milli units per base unit 316 const int MICROUNITS = 1000000; // micro units per base unit 317 const int NANOUNITS = 1000000000; // nano units per base unit 318 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS; 319 320 const jlong NANOSECS_PER_SEC = CONST64(1000000000); 321 const jint NANOSECS_PER_MILLISEC = 1000000; 322 323 324 // Unit conversion functions 325 // The caller is responsible for considering overflow. 326 327 inline int64_t nanos_to_millis(int64_t nanos) { 328 return nanos / NANOUNITS_PER_MILLIUNIT; 329 } 330 inline int64_t millis_to_nanos(int64_t millis) { 331 return millis * NANOUNITS_PER_MILLIUNIT; 332 } 333 334 // Proper units routines try to maintain at least three significant digits. 335 // In worst case, it would print five significant digits with lower prefix. 336 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow, 337 // and therefore we need to be careful. 338 339 inline const char* proper_unit_for_byte_size(size_t s) { 340 #ifdef _LP64 341 if (s >= 100*G) { 342 return "G"; 343 } 344 #endif 345 if (s >= 100*M) { 346 return "M"; 347 } else if (s >= 100*K) { 348 return "K"; 349 } else { 350 return "B"; 351 } 352 } 353 354 template <class T> 355 inline T byte_size_in_proper_unit(T s) { 356 #ifdef _LP64 357 if (s >= 100*G) { 358 return (T)(s/G); 359 } 360 #endif 361 if (s >= 100*M) { 362 return (T)(s/M); 363 } else if (s >= 100*K) { 364 return (T)(s/K); 365 } else { 366 return s; 367 } 368 } 369 370 #define PROPERFMT "%zu%s" 371 #define PROPERFMTARGS(s) byte_size_in_proper_unit(s), proper_unit_for_byte_size(s) 372 373 // Printing a range, with start and bytes given 374 #define RANGEFMT "[" PTR_FORMAT " - " PTR_FORMAT "), (%zu bytes)" 375 #define RANGEFMTARGS(p1, size) p2i(p1), p2i(p1 + size), size 376 377 // Printing a range, with start and end given 378 #define RANGE2FMT "[" PTR_FORMAT " - " PTR_FORMAT "), (%zu bytes)" 379 #define RANGE2FMTARGS(p1, p2) p2i(p1), p2i(p2), ((uintptr_t)p2 - (uintptr_t)p1) 380 381 inline const char* exact_unit_for_byte_size(size_t s) { 382 #ifdef _LP64 383 if (s >= G && (s % G) == 0) { 384 return "G"; 385 } 386 #endif 387 if (s >= M && (s % M) == 0) { 388 return "M"; 389 } 390 if (s >= K && (s % K) == 0) { 391 return "K"; 392 } 393 return "B"; 394 } 395 396 inline size_t byte_size_in_exact_unit(size_t s) { 397 #ifdef _LP64 398 if (s >= G && (s % G) == 0) { 399 return s / G; 400 } 401 #endif 402 if (s >= M && (s % M) == 0) { 403 return s / M; 404 } 405 if (s >= K && (s % K) == 0) { 406 return s / K; 407 } 408 return s; 409 } 410 411 #define EXACTFMT "%zu%s" 412 #define EXACTFMTARGS(s) byte_size_in_exact_unit(s), exact_unit_for_byte_size(s) 413 414 // Memory size transition formatting. 415 416 #define HEAP_CHANGE_FORMAT "%s: %zuK(%zuK)->%zuK(%zuK)" 417 418 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \ 419 (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K 420 421 //---------------------------------------------------------------------------------------------------- 422 // VM type definitions 423 424 // intx and uintx are the 'extended' int and 'extended' unsigned int types; 425 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform. 426 427 typedef intptr_t intx; 428 typedef uintptr_t uintx; 429 430 const intx min_intx = (intx)1 << (sizeof(intx)*BitsPerByte-1); 431 const intx max_intx = (uintx)min_intx - 1; 432 const uintx max_uintx = (uintx)-1; 433 434 // Table of values: 435 // sizeof intx 4 8 436 // min_intx 0x80000000 0x8000000000000000 437 // max_intx 0x7FFFFFFF 0x7FFFFFFFFFFFFFFF 438 // max_uintx 0xFFFFFFFF 0xFFFFFFFFFFFFFFFF 439 440 typedef unsigned int uint; NEEDS_CLEANUP 441 442 //---------------------------------------------------------------------------------------------------- 443 // Java type definitions 444 445 // All kinds of 'plain' byte addresses 446 typedef signed char s_char; 447 typedef unsigned char u_char; 448 typedef u_char* address; 449 typedef const u_char* const_address; 450 451 // Pointer subtraction. 452 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have 453 // the range we might need to find differences from one end of the heap 454 // to the other. 455 // A typical use might be: 456 // if (pointer_delta(end(), top()) >= size) { 457 // // enough room for an object of size 458 // ... 459 // and then additions like 460 // ... top() + size ... 461 // are safe because we know that top() is at least size below end(). 462 inline size_t pointer_delta(const volatile void* left, 463 const volatile void* right, 464 size_t element_size) { 465 assert(left >= right, "avoid underflow - left: " PTR_FORMAT " right: " PTR_FORMAT, p2i(left), p2i(right)); 466 return (((uintptr_t) left) - ((uintptr_t) right)) / element_size; 467 } 468 469 // A version specialized for HeapWord*'s. 470 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) { 471 return pointer_delta(left, right, sizeof(HeapWord)); 472 } 473 // A version specialized for MetaWord*'s. 474 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) { 475 return pointer_delta(left, right, sizeof(MetaWord)); 476 } 477 478 // pointer_delta_as_int is called to do pointer subtraction for nearby pointers that 479 // returns a non-negative int, usually used as a size of a code buffer range. 480 // This scales to sizeof(T). 481 template <typename T> 482 inline int pointer_delta_as_int(const volatile T* left, const volatile T* right) { 483 size_t delta = pointer_delta(left, right, sizeof(T)); 484 assert(delta <= size_t(INT_MAX), "pointer delta out of range: %zu", delta); 485 return static_cast<int>(delta); 486 } 487 488 // 489 // ANSI C++ does not allow casting from one pointer type to a function pointer 490 // directly without at best a warning. This macro accomplishes it silently 491 // In every case that is present at this point the value be cast is a pointer 492 // to a C linkage function. In some case the type used for the cast reflects 493 // that linkage and a picky compiler would not complain. In other cases because 494 // there is no convenient place to place a typedef with extern C linkage (i.e 495 // a platform dependent header file) it doesn't. At this point no compiler seems 496 // picky enough to catch these instances (which are few). It is possible that 497 // using templates could fix these for all cases. This use of templates is likely 498 // so far from the middle of the road that it is likely to be problematic in 499 // many C++ compilers. 500 // 501 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value)) 502 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((uintptr_t)(func_ptr))) 503 504 // Need the correct linkage to call qsort without warnings 505 extern "C" { 506 typedef int (*_sort_Fn)(const void *, const void *); 507 } 508 509 // Additional Java basic types 510 511 typedef uint8_t jubyte; 512 typedef uint16_t jushort; 513 typedef uint32_t juint; 514 typedef uint64_t julong; 515 516 // Unsigned byte types for os and stream.hpp 517 518 // Unsigned one, two, four and eight byte quantities used for describing 519 // the .class file format. See JVM book chapter 4. 520 521 typedef jubyte u1; 522 typedef jushort u2; 523 typedef juint u4; 524 typedef julong u8; 525 526 const jubyte max_jubyte = (jubyte)-1; // 0xFF largest jubyte 527 const jushort max_jushort = (jushort)-1; // 0xFFFF largest jushort 528 const juint max_juint = (juint)-1; // 0xFFFFFFFF largest juint 529 const julong max_julong = (julong)-1; // 0xFF....FF largest julong 530 531 typedef jbyte s1; 532 typedef jshort s2; 533 typedef jint s4; 534 typedef jlong s8; 535 536 const jbyte min_jbyte = -(1 << 7); // smallest jbyte 537 const jbyte max_jbyte = (1 << 7) - 1; // largest jbyte 538 const jshort min_jshort = -(1 << 15); // smallest jshort 539 const jshort max_jshort = (1 << 15) - 1; // largest jshort 540 541 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint 542 const jint max_jint = (juint)min_jint - 1; // 0x7FFFFFFF == largest jint 543 544 const jint min_jintFloat = (jint)(0x00000001); 545 const jfloat min_jfloat = jfloat_cast(min_jintFloat); 546 const jint max_jintFloat = (jint)(0x7f7fffff); 547 const jfloat max_jfloat = jfloat_cast(max_jintFloat); 548 549 const jshort max_jfloat16 = 31743; 550 const jshort min_jfloat16 = 1; 551 const jshort one_jfloat16 = 15360; 552 const jshort pos_inf_jfloat16 = 31744; 553 const jshort neg_inf_jfloat16 = -1024; 554 // A named constant for the integral representation of a Java null. 555 const intptr_t NULL_WORD = 0; 556 557 //---------------------------------------------------------------------------------------------------- 558 // JVM spec restrictions 559 560 const int max_method_code_size = 64*K - 1; // JVM spec, 2nd ed. section 4.8.1 (p.134) 561 562 //---------------------------------------------------------------------------------------------------- 563 // old CDS options 564 extern bool RequireSharedSpaces; 565 extern "C" { 566 // Make sure UseSharedSpaces is accessible to the serviceability agent. 567 extern JNIEXPORT jboolean UseSharedSpaces; 568 } 569 570 //---------------------------------------------------------------------------------------------------- 571 // Object alignment, in units of HeapWords. 572 // 573 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and 574 // reference fields can be naturally aligned. 575 576 extern int MinObjAlignment; 577 extern int MinObjAlignmentInBytes; 578 extern int MinObjAlignmentInBytesMask; 579 580 extern int LogMinObjAlignment; 581 extern int LogMinObjAlignmentInBytes; 582 583 // Maximal size of heap where unscaled compression can be used. Also upper bound 584 // for heap placement: 4GB. 585 const uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1); 586 // Maximal size of heap where compressed oops can be used. Also upper bound for heap 587 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes. 588 extern uint64_t OopEncodingHeapMax; 589 590 // Machine dependent stuff 591 592 #include CPU_HEADER(globalDefinitions) 593 594 // The maximum size of the code cache. Can be overridden by targets. 595 #ifndef CODE_CACHE_SIZE_LIMIT 596 #define CODE_CACHE_SIZE_LIMIT (2*G) 597 #endif 598 599 // Allow targets to reduce the default size of the code cache. 600 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT 601 602 // To assure the IRIW property on processors that are not multiple copy 603 // atomic, sync instructions must be issued between volatile reads to 604 // assure their ordering, instead of after volatile stores. 605 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models" 606 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge) 607 #ifdef CPU_MULTI_COPY_ATOMIC 608 // Not needed. 609 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false; 610 #else 611 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment. 612 // Final decision is subject to JEP 188: Java Memory Model Update. 613 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false); 614 #endif 615 616 // The expected size in bytes of a cache line. 617 #ifndef DEFAULT_CACHE_LINE_SIZE 618 #error "Platform should define DEFAULT_CACHE_LINE_SIZE" 619 #endif 620 621 // The default padding size for data structures to avoid false sharing. 622 #ifndef DEFAULT_PADDING_SIZE 623 #error "Platform should define DEFAULT_PADDING_SIZE" 624 #endif 625 626 627 //---------------------------------------------------------------------------------------------------- 628 // Miscellaneous 629 630 // 6302670 Eliminate Hotspot __fabsf dependency 631 // All fabs() callers should call this function instead, which will implicitly 632 // convert the operand to double, avoiding a dependency on __fabsf which 633 // doesn't exist in early versions of Solaris 8. 634 inline double fabsd(double value) { 635 return fabs(value); 636 } 637 638 // Returns numerator/denominator as percentage value from 0 to 100. If denominator 639 // is zero, return 0.0. 640 template<typename T> 641 inline double percent_of(T numerator, T denominator) { 642 return denominator != 0 ? (double)numerator / (double)denominator * 100.0 : 0.0; 643 } 644 645 //---------------------------------------------------------------------------------------------------- 646 // Special casts 647 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern 648 typedef union { 649 jfloat f; 650 jint i; 651 } FloatIntConv; 652 653 typedef union { 654 jdouble d; 655 jlong l; 656 julong ul; 657 } DoubleLongConv; 658 659 inline jint jint_cast (jfloat x) { return ((FloatIntConv*)&x)->i; } 660 inline jfloat jfloat_cast (jint x) { return ((FloatIntConv*)&x)->f; } 661 662 inline jlong jlong_cast (jdouble x) { return ((DoubleLongConv*)&x)->l; } 663 inline julong julong_cast (jdouble x) { return ((DoubleLongConv*)&x)->ul; } 664 inline jdouble jdouble_cast (jlong x) { return ((DoubleLongConv*)&x)->d; } 665 666 inline jint low (jlong value) { return jint(value); } 667 inline jint high(jlong value) { return jint(value >> 32); } 668 669 // the fancy casts are a hopefully portable way 670 // to do unsigned 32 to 64 bit type conversion 671 inline void set_low (jlong* value, jint low ) { *value &= (jlong)0xffffffff << 32; 672 *value |= (jlong)(julong)(juint)low; } 673 674 inline void set_high(jlong* value, jint high) { *value &= (jlong)(julong)(juint)0xffffffff; 675 *value |= (jlong)high << 32; } 676 677 inline jlong jlong_from(jint h, jint l) { 678 jlong result = 0; // initialization to avoid warning 679 set_high(&result, h); 680 set_low(&result, l); 681 return result; 682 } 683 684 union jlong_accessor { 685 jint words[2]; 686 jlong long_value; 687 }; 688 689 void basic_types_init(); // cannot define here; uses assert 690 691 692 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java 693 enum BasicType : u1 { 694 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS. 695 T_BOOLEAN = JVM_T_BOOLEAN, 696 T_CHAR = JVM_T_CHAR, 697 T_FLOAT = JVM_T_FLOAT, 698 T_DOUBLE = JVM_T_DOUBLE, 699 T_BYTE = JVM_T_BYTE, 700 T_SHORT = JVM_T_SHORT, 701 T_INT = JVM_T_INT, 702 T_LONG = JVM_T_LONG, 703 // The remaining values are not part of any standard. 704 // T_OBJECT and T_VOID denote two more semantic choices 705 // for method return values. 706 // T_OBJECT and T_ARRAY describe signature syntax. 707 // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe 708 // internal references within the JVM as if they were Java 709 // types in their own right. 710 T_OBJECT = 12, 711 T_ARRAY = 13, 712 T_VOID = 14, 713 T_ADDRESS = 15, 714 T_NARROWOOP = 16, 715 T_METADATA = 17, 716 T_NARROWKLASS = 18, 717 T_CONFLICT = 19, // for stack value type with conflicting contents 718 T_ILLEGAL = 99 719 }; 720 721 #define SIGNATURE_TYPES_DO(F, N) \ 722 F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N) \ 723 F(JVM_SIGNATURE_CHAR, T_CHAR, N) \ 724 F(JVM_SIGNATURE_FLOAT, T_FLOAT, N) \ 725 F(JVM_SIGNATURE_DOUBLE, T_DOUBLE, N) \ 726 F(JVM_SIGNATURE_BYTE, T_BYTE, N) \ 727 F(JVM_SIGNATURE_SHORT, T_SHORT, N) \ 728 F(JVM_SIGNATURE_INT, T_INT, N) \ 729 F(JVM_SIGNATURE_LONG, T_LONG, N) \ 730 F(JVM_SIGNATURE_CLASS, T_OBJECT, N) \ 731 F(JVM_SIGNATURE_ARRAY, T_ARRAY, N) \ 732 F(JVM_SIGNATURE_VOID, T_VOID, N) \ 733 /*end*/ 734 735 inline bool is_java_type(BasicType t) { 736 return T_BOOLEAN <= t && t <= T_VOID; 737 } 738 739 inline bool is_java_primitive(BasicType t) { 740 return T_BOOLEAN <= t && t <= T_LONG; 741 } 742 743 inline bool is_subword_type(BasicType t) { 744 // these guys are processed exactly like T_INT in calling sequences: 745 return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT); 746 } 747 748 inline bool is_signed_subword_type(BasicType t) { 749 return (t == T_BYTE || t == T_SHORT); 750 } 751 752 inline bool is_unsigned_subword_type(BasicType t) { 753 return (t == T_BOOLEAN || t == T_CHAR); 754 } 755 756 inline bool is_double_word_type(BasicType t) { 757 return (t == T_DOUBLE || t == T_LONG); 758 } 759 760 inline bool is_reference_type(BasicType t, bool include_narrow_oop = false) { 761 return (t == T_OBJECT || t == T_ARRAY || (include_narrow_oop && t == T_NARROWOOP)); 762 } 763 764 inline bool is_integral_type(BasicType t) { 765 return is_subword_type(t) || t == T_INT || t == T_LONG; 766 } 767 768 inline bool is_non_subword_integral_type(BasicType t) { 769 return t == T_INT || t == T_LONG; 770 } 771 772 inline bool is_floating_point_type(BasicType t) { 773 return (t == T_FLOAT || t == T_DOUBLE); 774 } 775 776 extern char type2char_tab[T_CONFLICT+1]; // Map a BasicType to a jchar 777 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; } 778 extern int type2size[T_CONFLICT+1]; // Map BasicType to result stack elements 779 extern const char* type2name_tab[T_CONFLICT+1]; // Map a BasicType to a char* 780 extern BasicType name2type(const char* name); 781 782 const char* type2name(BasicType t); 783 784 inline jlong max_signed_integer(BasicType bt) { 785 if (bt == T_INT) { 786 return max_jint; 787 } 788 assert(bt == T_LONG, "unsupported"); 789 return max_jlong; 790 } 791 792 inline jlong min_signed_integer(BasicType bt) { 793 if (bt == T_INT) { 794 return min_jint; 795 } 796 assert(bt == T_LONG, "unsupported"); 797 return min_jlong; 798 } 799 800 inline uint bits_per_java_integer(BasicType bt) { 801 if (bt == T_INT) { 802 return BitsPerJavaInteger; 803 } 804 assert(bt == T_LONG, "int or long only"); 805 return BitsPerJavaLong; 806 } 807 808 // Auxiliary math routines 809 // least common multiple 810 extern size_t lcm(size_t a, size_t b); 811 812 813 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java 814 enum BasicTypeSize { 815 T_BOOLEAN_size = 1, 816 T_CHAR_size = 1, 817 T_FLOAT_size = 1, 818 T_DOUBLE_size = 2, 819 T_BYTE_size = 1, 820 T_SHORT_size = 1, 821 T_INT_size = 1, 822 T_LONG_size = 2, 823 T_OBJECT_size = 1, 824 T_ARRAY_size = 1, 825 T_NARROWOOP_size = 1, 826 T_NARROWKLASS_size = 1, 827 T_VOID_size = 0 828 }; 829 830 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc. 831 inline int parameter_type_word_count(BasicType t) { 832 if (is_double_word_type(t)) return 2; 833 assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please"); 834 assert(type2size[t] == 1, "must be"); 835 return 1; 836 } 837 838 // maps a BasicType to its instance field storage type: 839 // all sub-word integral types are widened to T_INT 840 extern BasicType type2field[T_CONFLICT+1]; 841 extern BasicType type2wfield[T_CONFLICT+1]; 842 843 844 // size in bytes 845 enum ArrayElementSize { 846 T_BOOLEAN_aelem_bytes = 1, 847 T_CHAR_aelem_bytes = 2, 848 T_FLOAT_aelem_bytes = 4, 849 T_DOUBLE_aelem_bytes = 8, 850 T_BYTE_aelem_bytes = 1, 851 T_SHORT_aelem_bytes = 2, 852 T_INT_aelem_bytes = 4, 853 T_LONG_aelem_bytes = 8, 854 #ifdef _LP64 855 T_OBJECT_aelem_bytes = 8, 856 T_ARRAY_aelem_bytes = 8, 857 #else 858 T_OBJECT_aelem_bytes = 4, 859 T_ARRAY_aelem_bytes = 4, 860 #endif 861 T_NARROWOOP_aelem_bytes = 4, 862 T_NARROWKLASS_aelem_bytes = 4, 863 T_VOID_aelem_bytes = 0 864 }; 865 866 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element 867 #ifdef ASSERT 868 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts 869 #else 870 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; } 871 #endif 872 873 inline bool same_type_or_subword_size(BasicType t1, BasicType t2) { 874 return (t1 == t2) || (is_subword_type(t1) && type2aelembytes(t1) == type2aelembytes(t2)); 875 } 876 877 // JavaValue serves as a container for arbitrary Java values. 878 879 class JavaValue { 880 881 public: 882 typedef union JavaCallValue { 883 jfloat f; 884 jdouble d; 885 jint i; 886 jlong l; 887 jobject h; 888 oopDesc* o; 889 } JavaCallValue; 890 891 private: 892 BasicType _type; 893 JavaCallValue _value; 894 895 public: 896 JavaValue(BasicType t = T_ILLEGAL) { _type = t; } 897 898 JavaValue(jfloat value) { 899 _type = T_FLOAT; 900 _value.f = value; 901 } 902 903 JavaValue(jdouble value) { 904 _type = T_DOUBLE; 905 _value.d = value; 906 } 907 908 jfloat get_jfloat() const { return _value.f; } 909 jdouble get_jdouble() const { return _value.d; } 910 jint get_jint() const { return _value.i; } 911 jlong get_jlong() const { return _value.l; } 912 jobject get_jobject() const { return _value.h; } 913 oopDesc* get_oop() const { return _value.o; } 914 JavaCallValue* get_value_addr() { return &_value; } 915 BasicType get_type() const { return _type; } 916 917 void set_jfloat(jfloat f) { _value.f = f;} 918 void set_jdouble(jdouble d) { _value.d = d;} 919 void set_jint(jint i) { _value.i = i;} 920 void set_jshort(jshort i) { _value.i = i;} 921 void set_jlong(jlong l) { _value.l = l;} 922 void set_jobject(jobject h) { _value.h = h;} 923 void set_oop(oopDesc* o) { _value.o = o;} 924 void set_type(BasicType t) { _type = t; } 925 926 jboolean get_jboolean() const { return (jboolean) (_value.i);} 927 jbyte get_jbyte() const { return (jbyte) (_value.i);} 928 jchar get_jchar() const { return (jchar) (_value.i);} 929 jshort get_jshort() const { return (jshort) (_value.i);} 930 931 }; 932 933 934 // TosState describes the top-of-stack state before and after the execution of 935 // a bytecode or method. The top-of-stack value may be cached in one or more CPU 936 // registers. The TosState corresponds to the 'machine representation' of this cached 937 // value. There's 4 states corresponding to the JAVA types int, long, float & double 938 // as well as a 5th state in case the top-of-stack value is actually on the top 939 // of stack (in memory) and thus not cached. The atos state corresponds to the itos 940 // state when it comes to machine representation but is used separately for (oop) 941 // type specific operations (e.g. verification code). 942 943 enum TosState { // describes the tos cache contents 944 btos = 0, // byte, bool tos cached 945 ztos = 1, // byte, bool tos cached 946 ctos = 2, // char tos cached 947 stos = 3, // short tos cached 948 itos = 4, // int tos cached 949 ltos = 5, // long tos cached 950 ftos = 6, // float tos cached 951 dtos = 7, // double tos cached 952 atos = 8, // object cached 953 vtos = 9, // tos not cached 954 number_of_states, 955 ilgl // illegal state: should not occur 956 }; 957 958 959 inline TosState as_TosState(BasicType type) { 960 switch (type) { 961 case T_BYTE : return btos; 962 case T_BOOLEAN: return ztos; 963 case T_CHAR : return ctos; 964 case T_SHORT : return stos; 965 case T_INT : return itos; 966 case T_LONG : return ltos; 967 case T_FLOAT : return ftos; 968 case T_DOUBLE : return dtos; 969 case T_VOID : return vtos; 970 case T_ARRAY : // fall through 971 case T_OBJECT : return atos; 972 default : return ilgl; 973 } 974 } 975 976 inline BasicType as_BasicType(TosState state) { 977 switch (state) { 978 case btos : return T_BYTE; 979 case ztos : return T_BOOLEAN; 980 case ctos : return T_CHAR; 981 case stos : return T_SHORT; 982 case itos : return T_INT; 983 case ltos : return T_LONG; 984 case ftos : return T_FLOAT; 985 case dtos : return T_DOUBLE; 986 case atos : return T_OBJECT; 987 case vtos : return T_VOID; 988 default : return T_ILLEGAL; 989 } 990 } 991 992 993 // Helper function to convert BasicType info into TosState 994 // Note: Cannot define here as it uses global constant at the time being. 995 TosState as_TosState(BasicType type); 996 997 998 // JavaThreadState keeps track of which part of the code a thread is executing in. This 999 // information is needed by the safepoint code. 1000 // 1001 // There are 4 essential states: 1002 // 1003 // _thread_new : Just started, but not executed init. code yet (most likely still in OS init code) 1004 // _thread_in_native : In native code. This is a safepoint region, since all oops will be in jobject handles 1005 // _thread_in_vm : Executing in the vm 1006 // _thread_in_Java : Executing either interpreted or compiled Java code (or could be in a stub) 1007 // 1008 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in 1009 // a transition from one state to another. These extra states makes it possible for the safepoint code to 1010 // handle certain thread_states without having to suspend the thread - making the safepoint code faster. 1011 // 1012 // Given a state, the xxxx_trans state can always be found by adding 1. 1013 // 1014 enum JavaThreadState { 1015 _thread_uninitialized = 0, // should never happen (missing initialization) 1016 _thread_new = 2, // just starting up, i.e., in process of being initialized 1017 _thread_new_trans = 3, // corresponding transition state (not used, included for completeness) 1018 _thread_in_native = 4, // running in native code 1019 _thread_in_native_trans = 5, // corresponding transition state 1020 _thread_in_vm = 6, // running in VM 1021 _thread_in_vm_trans = 7, // corresponding transition state 1022 _thread_in_Java = 8, // running in Java or in stub code 1023 _thread_in_Java_trans = 9, // corresponding transition state (not used, included for completeness) 1024 _thread_blocked = 10, // blocked in vm 1025 _thread_blocked_trans = 11, // corresponding transition state 1026 _thread_max_state = 12 // maximum thread state+1 - used for statistics allocation 1027 }; 1028 1029 enum LockingMode { 1030 // Use only heavy monitors for locking 1031 LM_MONITOR = 0, 1032 // Legacy stack-locking, with monitors as 2nd tier 1033 LM_LEGACY = 1, 1034 // New lightweight locking, with monitors as 2nd tier 1035 LM_LIGHTWEIGHT = 2 1036 }; 1037 1038 //---------------------------------------------------------------------------------------------------- 1039 // Special constants for debugging 1040 1041 const jint badInt = -3; // generic "bad int" value 1042 const intptr_t badAddressVal = -2; // generic "bad address" value 1043 const intptr_t badOopVal = -1; // generic "bad oop" value 1044 const intptr_t badHeapOopVal = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC 1045 const int badStackSegVal = 0xCA; // value used to zap stack segments 1046 const int badHandleValue = 0xBC; // value used to zap vm handle area 1047 const int badResourceValue = 0xAB; // value used to zap resource area 1048 const int freeBlockPad = 0xBA; // value used to pad freed blocks. 1049 const int uninitBlockPad = 0xF1; // value used to zap newly malloc'd blocks. 1050 const juint uninitMetaWordVal = 0xf7f7f7f7; // value used to zap newly allocated metachunk 1051 const jubyte heapPaddingByteVal = 0xBD; // value used to zap object padding in the heap 1052 const juint badHeapWordVal = 0xBAADBABE; // value used to zap heap after GC 1053 const int badCodeHeapNewVal = 0xCC; // value used to zap Code heap at allocation 1054 const int badCodeHeapFreeVal = 0xDD; // value used to zap Code heap at deallocation 1055 const intptr_t badDispHeaderDeopt = 0xDE0BD000; // value to fill unused displaced header during deoptimization 1056 const intptr_t badDispHeaderOSR = 0xDEAD05A0; // value to fill unused displaced header during OSR 1057 1058 // (These must be implemented as #defines because C++ compilers are 1059 // not obligated to inline non-integral constants!) 1060 #define badAddress ((address)::badAddressVal) 1061 #define badHeapWord (::badHeapWordVal) 1062 1063 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit) 1064 const uint TASKQUEUE_SIZE = (NOT_LP64(1<<14) LP64_ONLY(1<<17)); 1065 1066 //---------------------------------------------------------------------------------------------------- 1067 // Utility functions for bitfield manipulations 1068 1069 const intptr_t AllBits = ~0; // all bits set in a word 1070 const intptr_t NoBits = 0; // no bits set in a word 1071 const jlong NoLongBits = 0; // no bits set in a long 1072 const intptr_t OneBit = 1; // only right_most bit set in a word 1073 1074 // get a word with the n.th or the right-most or left-most n bits set 1075 // (note: #define used only so that they can be used in enum constant definitions) 1076 #define nth_bit(n) (((n) >= BitsPerWord) ? 0 : (OneBit << (n))) 1077 #define right_n_bits(n) (nth_bit(n) - 1) 1078 1079 // bit-operations using a mask m 1080 inline void set_bits (intptr_t& x, intptr_t m) { x |= m; } 1081 inline void clear_bits (intptr_t& x, intptr_t m) { x &= ~m; } 1082 inline intptr_t mask_bits (intptr_t x, intptr_t m) { return x & m; } 1083 inline jlong mask_long_bits (jlong x, jlong m) { return x & m; } 1084 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; } 1085 1086 // bit-operations using the n.th bit 1087 inline void set_nth_bit(intptr_t& x, int n) { set_bits (x, nth_bit(n)); } 1088 inline void clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); } 1089 inline bool is_set_nth_bit(intptr_t x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; } 1090 1091 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!) 1092 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) { 1093 return mask_bits(x >> start_bit_no, right_n_bits(field_length)); 1094 } 1095 1096 1097 //---------------------------------------------------------------------------------------------------- 1098 // Utility functions for integers 1099 1100 // Avoid use of global min/max macros which may cause unwanted double 1101 // evaluation of arguments. 1102 #ifdef max 1103 #undef max 1104 #endif 1105 1106 #ifdef min 1107 #undef min 1108 #endif 1109 1110 // It is necessary to use templates here. Having normal overloaded 1111 // functions does not work because it is necessary to provide both 32- 1112 // and 64-bit overloaded functions, which does not work, and having 1113 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L) 1114 // will be even more error-prone than macros. 1115 template<class T> constexpr T MAX2(T a, T b) { return (a > b) ? a : b; } 1116 template<class T> constexpr T MIN2(T a, T b) { return (a < b) ? a : b; } 1117 template<class T> constexpr T MAX3(T a, T b, T c) { return MAX2(MAX2(a, b), c); } 1118 template<class T> constexpr T MIN3(T a, T b, T c) { return MIN2(MIN2(a, b), c); } 1119 template<class T> constexpr T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); } 1120 template<class T> constexpr T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); } 1121 1122 #define ABS(x) asserted_abs(x, __FILE__, __LINE__) 1123 1124 template<class T> inline T asserted_abs(T x, const char* file, int line) { 1125 bool valid_arg = !(std::is_integral<T>::value && x == std::numeric_limits<T>::min()); 1126 #ifdef ASSERT 1127 if (!valid_arg) { 1128 report_vm_error(file, line, "ABS: argument should not allow overflow"); 1129 } 1130 #endif 1131 // Prevent exposure to UB by checking valid_arg here as well. 1132 return (x < 0 && valid_arg) ? -x : x; 1133 } 1134 1135 // Return the given value clamped to the range [min ... max] 1136 template<typename T> 1137 inline T clamp(T value, T min, T max) { 1138 assert(min <= max, "must be"); 1139 return MIN2(MAX2(value, min), max); 1140 } 1141 1142 inline bool is_odd (intx x) { return x & 1; } 1143 inline bool is_even(intx x) { return !is_odd(x); } 1144 1145 // abs methods which cannot overflow and so are well-defined across 1146 // the entire domain of integer types. 1147 static inline unsigned int uabs(unsigned int n) { 1148 union { 1149 unsigned int result; 1150 int value; 1151 }; 1152 result = n; 1153 if (value < 0) result = 0-result; 1154 return result; 1155 } 1156 static inline julong uabs(julong n) { 1157 union { 1158 julong result; 1159 jlong value; 1160 }; 1161 result = n; 1162 if (value < 0) result = 0-result; 1163 return result; 1164 } 1165 static inline julong uabs(jlong n) { return uabs((julong)n); } 1166 static inline unsigned int uabs(int n) { return uabs((unsigned int)n); } 1167 1168 // "to" should be greater than "from." 1169 inline size_t byte_size(void* from, void* to) { 1170 return pointer_delta(to, from, sizeof(char)); 1171 } 1172 1173 // Pack and extract shorts to/from ints: 1174 1175 inline u2 extract_low_short_from_int(u4 x) { 1176 return u2(x & 0xffff); 1177 } 1178 1179 inline u2 extract_high_short_from_int(u4 x) { 1180 return u2((x >> 16) & 0xffff); 1181 } 1182 1183 inline int build_int_from_shorts( u2 low, u2 high ) { 1184 return ((int)((unsigned int)high << 16) | (unsigned int)low); 1185 } 1186 1187 // swap a & b 1188 template<class T> static void swap(T& a, T& b) { 1189 T tmp = a; 1190 a = b; 1191 b = tmp; 1192 } 1193 1194 // array_size_impl is a function that takes a reference to T[N] and 1195 // returns a reference to char[N]. It is not ODR-used, so not defined. 1196 template<typename T, size_t N> char (&array_size_impl(T (&)[N]))[N]; 1197 1198 #define ARRAY_SIZE(array) sizeof(array_size_impl(array)) 1199 1200 //---------------------------------------------------------------------------------------------------- 1201 // Sum and product which can never overflow: they wrap, just like the 1202 // Java operations. Note that we don't intend these to be used for 1203 // general-purpose arithmetic: their purpose is to emulate Java 1204 // operations. 1205 1206 // The goal of this code to avoid undefined or implementation-defined 1207 // behavior. The use of an lvalue to reference cast is explicitly 1208 // permitted by Lvalues and rvalues [basic.lval]. [Section 3.10 Para 1209 // 15 in C++03] 1210 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE) \ 1211 inline TYPE NAME (TYPE in1, TYPE in2) { \ 1212 UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \ 1213 ures OP ## = static_cast<UNSIGNED_TYPE>(in2); \ 1214 return reinterpret_cast<TYPE&>(ures); \ 1215 } 1216 1217 JAVA_INTEGER_OP(+, java_add, jint, juint) 1218 JAVA_INTEGER_OP(-, java_subtract, jint, juint) 1219 JAVA_INTEGER_OP(*, java_multiply, jint, juint) 1220 JAVA_INTEGER_OP(+, java_add, jlong, julong) 1221 JAVA_INTEGER_OP(-, java_subtract, jlong, julong) 1222 JAVA_INTEGER_OP(*, java_multiply, jlong, julong) 1223 1224 inline jint java_negate(jint v) { return java_subtract((jint) 0, v); } 1225 inline jlong java_negate(jlong v) { return java_subtract((jlong)0, v); } 1226 1227 #undef JAVA_INTEGER_OP 1228 1229 // Provide integer shift operations with Java semantics. No overflow 1230 // issues - left shifts simply discard shifted out bits. No undefined 1231 // behavior for large or negative shift quantities; instead the actual 1232 // shift distance is the argument modulo the lhs value's size in bits. 1233 // No undefined or implementation defined behavior for shifting negative 1234 // values; left shift discards bits, right shift sign extends. We use 1235 // the same safe conversion technique as above for java_add and friends. 1236 #define JAVA_INTEGER_SHIFT_OP(OP, NAME, TYPE, XTYPE) \ 1237 inline TYPE NAME (TYPE lhs, jint rhs) { \ 1238 const uint rhs_mask = (sizeof(TYPE) * 8) - 1; \ 1239 STATIC_ASSERT(rhs_mask == 31 || rhs_mask == 63); \ 1240 XTYPE xres = static_cast<XTYPE>(lhs); \ 1241 xres OP ## = (rhs & rhs_mask); \ 1242 return reinterpret_cast<TYPE&>(xres); \ 1243 } 1244 1245 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jint, juint) 1246 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jlong, julong) 1247 1248 // For signed shift right, assume C++ implementation >> sign extends. 1249 // 1250 // C++14 5.8/3: In the description of "E1 >> E2" it says "If E1 has a signed type 1251 // and a negative value, the resulting value is implementation-defined." 1252 // 1253 // However, C++20 7.6.7/3 further defines integral arithmetic, as part of 1254 // requiring two's-complement behavior. 1255 // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0907r3.html 1256 // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1236r1.html 1257 // The corresponding C++20 text is "Right-shift on signed integral types is an 1258 // arithmetic right shift, which performs sign-extension." 1259 // 1260 // As discussed in the two's complement proposal, all known modern C++ compilers 1261 // already behave that way. And it is unlikely any would go off and do something 1262 // different now, with C++20 tightening things up. 1263 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jint, jint) 1264 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jlong, jlong) 1265 // For >>> use C++ unsigned >>. 1266 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jint, juint) 1267 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jlong, julong) 1268 1269 #undef JAVA_INTEGER_SHIFT_OP 1270 1271 //---------------------------------------------------------------------------------------------------- 1272 // The goal of this code is to provide saturating operations for int/uint. 1273 // Checks overflow conditions and saturates the result to min_jint/max_jint. 1274 #define SATURATED_INTEGER_OP(OP, NAME, TYPE1, TYPE2) \ 1275 inline int NAME (TYPE1 in1, TYPE2 in2) { \ 1276 jlong res = static_cast<jlong>(in1); \ 1277 res OP ## = static_cast<jlong>(in2); \ 1278 if (res > max_jint) { \ 1279 res = max_jint; \ 1280 } else if (res < min_jint) { \ 1281 res = min_jint; \ 1282 } \ 1283 return static_cast<int>(res); \ 1284 } 1285 1286 SATURATED_INTEGER_OP(+, saturated_add, int, int) 1287 SATURATED_INTEGER_OP(+, saturated_add, int, uint) 1288 SATURATED_INTEGER_OP(+, saturated_add, uint, int) 1289 SATURATED_INTEGER_OP(+, saturated_add, uint, uint) 1290 1291 #undef SATURATED_INTEGER_OP 1292 1293 // Taken from rom section 8-2 of Henry S. Warren, Jr., Hacker's Delight (2nd ed.) (Addison Wesley, 2013), 173-174. 1294 inline uint64_t multiply_high_unsigned(const uint64_t x, const uint64_t y) { 1295 const uint64_t x1 = x >> 32u; 1296 const uint64_t x2 = x & 0xFFFFFFFF; 1297 const uint64_t y1 = y >> 32u; 1298 const uint64_t y2 = y & 0xFFFFFFFF; 1299 const uint64_t z2 = x2 * y2; 1300 const uint64_t t = x1 * y2 + (z2 >> 32u); 1301 uint64_t z1 = t & 0xFFFFFFFF; 1302 const uint64_t z0 = t >> 32u; 1303 z1 += x2 * y1; 1304 1305 return x1 * y1 + z0 + (z1 >> 32u); 1306 } 1307 1308 // Taken from java.lang.Math::multiplyHigh which uses the technique from section 8-2 of Henry S. Warren, Jr., 1309 // Hacker's Delight (2nd ed.) (Addison Wesley, 2013), 173-174 but adapted for signed longs. 1310 inline int64_t multiply_high_signed(const int64_t x, const int64_t y) { 1311 const jlong x1 = java_shift_right((jlong)x, 32); 1312 const jlong x2 = x & 0xFFFFFFFF; 1313 const jlong y1 = java_shift_right((jlong)y, 32); 1314 const jlong y2 = y & 0xFFFFFFFF; 1315 1316 const uint64_t z2 = (uint64_t)x2 * y2; 1317 const int64_t t = x1 * y2 + (z2 >> 32u); // Unsigned shift 1318 int64_t z1 = t & 0xFFFFFFFF; 1319 const int64_t z0 = java_shift_right((jlong)t, 32); 1320 z1 += x2 * y1; 1321 1322 return x1 * y1 + z0 + java_shift_right((jlong)z1, 32); 1323 } 1324 1325 // Dereference vptr 1326 // All C++ compilers that we know of have the vtbl pointer in the first 1327 // word. If there are exceptions, this function needs to be made compiler 1328 // specific. 1329 static inline void* dereference_vptr(const void* addr) { 1330 return *(void**)addr; 1331 } 1332 1333 //---------------------------------------------------------------------------------------------------- 1334 // String type aliases used by command line flag declarations and 1335 // processing utilities. 1336 1337 typedef const char* ccstr; 1338 typedef const char* ccstrlist; // represents string arguments which accumulate 1339 1340 //---------------------------------------------------------------------------------------------------- 1341 // Default hash/equals functions used by ResourceHashtable 1342 1343 template<typename K> unsigned primitive_hash(const K& k) { 1344 unsigned hash = (unsigned)((uintptr_t)k); 1345 return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs 1346 } 1347 1348 template<typename K> bool primitive_equals(const K& k0, const K& k1) { 1349 return k0 == k1; 1350 } 1351 1352 template<typename K> int primitive_compare(const K& k0, const K& k1) { 1353 return ((k0 < k1) ? -1 : (k0 == k1) ? 0 : 1); 1354 } 1355 1356 //---------------------------------------------------------------------------------------------------- 1357 1358 // Allow use of C++ thread_local when approved - see JDK-8282469. 1359 #define APPROVED_CPP_THREAD_LOCAL thread_local 1360 1361 // Converts any type T to a reference type. 1362 template<typename T> 1363 std::add_rvalue_reference_t<T> declval() noexcept; 1364 1365 // Quickly test to make sure IEEE-754 subnormal numbers are correctly 1366 // handled. 1367 bool IEEE_subnormal_handling_OK(); 1368 1369 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP