1 /* 2 * Copyright (c) 1997, 2023, 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/attributeNoreturn.hpp" 29 #include "utilities/compilerWarnings.hpp" 30 #include "utilities/debug.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 <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) 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 // 103 // Note that the PTR format specifiers print using 0x with leading zeros, 104 // just like the _X_0 version for integers. 105 106 // Format 8-bit quantities. 107 #define INT8_FORMAT_X_0 "0x%02" PRIx8 108 #define UINT8_FORMAT_X_0 "0x%02" PRIx8 109 110 // Format 16-bit quantities. 111 #define INT16_FORMAT_X_0 "0x%04" PRIx16 112 #define UINT16_FORMAT_X_0 "0x%04" PRIx16 113 114 // Format 32-bit quantities. 115 #define INT32_FORMAT "%" PRId32 116 #define INT32_FORMAT_X "0x%" PRIx32 117 #define INT32_FORMAT_X_0 "0x%08" PRIx32 118 #define INT32_FORMAT_W(width) "%" #width PRId32 119 #define UINT32_FORMAT "%" PRIu32 120 #define UINT32_FORMAT_X "0x%" PRIx32 121 #define UINT32_FORMAT_X_0 "0x%08" PRIx32 122 #define UINT32_FORMAT_W(width) "%" #width PRIu32 123 124 // Format 64-bit quantities. 125 #define INT64_FORMAT "%" PRId64 126 #define INT64_PLUS_FORMAT "%+" PRId64 127 #define INT64_FORMAT_X "0x%" PRIx64 128 #define INT64_FORMAT_X_0 "0x%016" PRIx64 129 #define INT64_FORMAT_W(width) "%" #width PRId64 130 #define UINT64_FORMAT "%" PRIu64 131 #define UINT64_FORMAT_X "0x%" PRIx64 132 #define UINT64_FORMAT_X_0 "0x%016" PRIx64 133 #define UINT64_FORMAT_W(width) "%" #width PRIu64 134 135 // Format integers which change size between 32- and 64-bit. 136 #define SSIZE_FORMAT "%" PRIdPTR 137 #define SSIZE_PLUS_FORMAT "%+" PRIdPTR 138 #define SSIZE_FORMAT_W(width) "%" #width PRIdPTR 139 #define SIZE_FORMAT "%" PRIuPTR 140 #define SIZE_FORMAT_X "0x%" PRIxPTR 141 #ifdef _LP64 142 #define SIZE_FORMAT_X_0 "0x%016" PRIxPTR 143 #else 144 #define SIZE_FORMAT_X_0 "0x%08" PRIxPTR 145 #endif 146 #define SIZE_FORMAT_W(width) "%" #width PRIuPTR 147 148 #define INTX_FORMAT "%" PRIdPTR 149 #define INTX_FORMAT_X "0x%" PRIxPTR 150 #define INTX_FORMAT_W(width) "%" #width PRIdPTR 151 #define UINTX_FORMAT "%" PRIuPTR 152 #define UINTX_FORMAT_X "0x%" PRIxPTR 153 #define UINTX_FORMAT_W(width) "%" #width PRIuPTR 154 155 // Format jlong, if necessary 156 #ifndef JLONG_FORMAT 157 #define JLONG_FORMAT INT64_FORMAT 158 #endif 159 #ifndef JLONG_FORMAT_W 160 #define JLONG_FORMAT_W(width) INT64_FORMAT_W(width) 161 #endif 162 #ifndef JULONG_FORMAT 163 #define JULONG_FORMAT UINT64_FORMAT 164 #endif 165 #ifndef JULONG_FORMAT_X 166 #define JULONG_FORMAT_X UINT64_FORMAT_X 167 #endif 168 169 // Format pointers which change size between 32- and 64-bit. 170 #ifdef _LP64 171 #define INTPTR_FORMAT "0x%016" PRIxPTR 172 #define PTR_FORMAT "0x%016" PRIxPTR 173 #else // !_LP64 174 #define INTPTR_FORMAT "0x%08" PRIxPTR 175 #define PTR_FORMAT "0x%08" PRIxPTR 176 #endif // _LP64 177 178 // Convert pointer to intptr_t, for use in printing pointers. 179 inline intptr_t p2i(const volatile void* p) { 180 return (intptr_t) p; 181 } 182 183 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false") 184 185 //---------------------------------------------------------------------------------------------------- 186 // Forbid the use of various C library functions. 187 // Some of these have os:: replacements that should normally be used instead. 188 // Others are considered security concerns, with preferred alternatives. 189 190 FORBID_C_FUNCTION(void exit(int), "use os::exit"); 191 FORBID_C_FUNCTION(void _exit(int), "use os::exit"); 192 FORBID_C_FUNCTION(char* strerror(int), "use os::strerror"); 193 FORBID_C_FUNCTION(char* strtok(char*, const char*), "use strtok_r"); 194 FORBID_C_FUNCTION(int sprintf(char*, const char*, ...), "use os::snprintf"); 195 FORBID_C_FUNCTION(int vsprintf(char*, const char*, va_list), "use os::vsnprintf"); 196 FORBID_C_FUNCTION(int vsnprintf(char*, size_t, const char*, va_list), "use os::vsnprintf"); 197 198 // All of the following functions return raw C-heap pointers (sometimes as an option, e.g. realpath or getwd) 199 // or, in case of free(), take raw C-heap pointers. Don't use them unless you are really sure you must. 200 FORBID_C_FUNCTION(void* malloc(size_t size), "use os::malloc"); 201 FORBID_C_FUNCTION(void* calloc(size_t nmemb, size_t size), "use os::malloc and zero out manually"); 202 FORBID_C_FUNCTION(void free(void *ptr), "use os::free"); 203 FORBID_C_FUNCTION(void* realloc(void *ptr, size_t size), "use os::realloc"); 204 FORBID_C_FUNCTION(char* strdup(const char *s), "use os::strdup"); 205 FORBID_C_FUNCTION(char* strndup(const char *s, size_t n), "don't use"); 206 FORBID_C_FUNCTION(int posix_memalign(void **memptr, size_t alignment, size_t size), "don't use"); 207 FORBID_C_FUNCTION(void* aligned_alloc(size_t alignment, size_t size), "don't use"); 208 FORBID_C_FUNCTION(char* realpath(const char* path, char* resolved_path), "use os::Posix::realpath"); 209 FORBID_C_FUNCTION(char* get_current_dir_name(void), "use os::get_current_directory()"); 210 FORBID_C_FUNCTION(char* getwd(char *buf), "use os::get_current_directory()"); 211 FORBID_C_FUNCTION(wchar_t* wcsdup(const wchar_t *s), "don't use"); 212 FORBID_C_FUNCTION(void* reallocf(void *ptr, size_t size), "don't use"); 213 214 //---------------------------------------------------------------------------------------------------- 215 // Constants 216 217 const int LogBytesPerShort = 1; 218 const int LogBytesPerInt = 2; 219 #ifdef _LP64 220 const int LogBytesPerWord = 3; 221 #else 222 const int LogBytesPerWord = 2; 223 #endif 224 const int LogBytesPerLong = 3; 225 226 const int BytesPerShort = 1 << LogBytesPerShort; 227 const int BytesPerInt = 1 << LogBytesPerInt; 228 const int BytesPerWord = 1 << LogBytesPerWord; 229 const int BytesPerLong = 1 << LogBytesPerLong; 230 231 const int LogBitsPerByte = 3; 232 const int LogBitsPerShort = LogBitsPerByte + LogBytesPerShort; 233 const int LogBitsPerInt = LogBitsPerByte + LogBytesPerInt; 234 const int LogBitsPerWord = LogBitsPerByte + LogBytesPerWord; 235 const int LogBitsPerLong = LogBitsPerByte + LogBytesPerLong; 236 237 const int BitsPerByte = 1 << LogBitsPerByte; 238 const int BitsPerShort = 1 << LogBitsPerShort; 239 const int BitsPerInt = 1 << LogBitsPerInt; 240 const int BitsPerWord = 1 << LogBitsPerWord; 241 const int BitsPerLong = 1 << LogBitsPerLong; 242 243 const int WordAlignmentMask = (1 << LogBytesPerWord) - 1; 244 const int LongAlignmentMask = (1 << LogBytesPerLong) - 1; 245 246 const int WordsPerLong = 2; // Number of stack entries for longs 247 248 const int oopSize = sizeof(char*); // Full-width oop 249 extern int heapOopSize; // Oop within a java object 250 const int wordSize = sizeof(char*); 251 const int longSize = sizeof(jlong); 252 const int jintSize = sizeof(jint); 253 const int size_tSize = sizeof(size_t); 254 255 const int BytesPerOop = BytesPerWord; // Full-width oop 256 257 extern int LogBytesPerHeapOop; // Oop within a java object 258 extern int LogBitsPerHeapOop; 259 extern int BytesPerHeapOop; 260 extern int BitsPerHeapOop; 261 262 const int BitsPerJavaInteger = 32; 263 const int BitsPerJavaLong = 64; 264 const int BitsPerSize_t = size_tSize * BitsPerByte; 265 266 // Size of a char[] needed to represent a jint as a string in decimal. 267 const int jintAsStringSize = 12; 268 269 // An opaque type, so that HeapWord* can be a generic pointer into the heap. 270 // We require that object sizes be measured in units of heap words (e.g. 271 // pointer-sized values), so that given HeapWord* hw, 272 // hw += oop(hw)->foo(); 273 // works, where foo is a method (like size or scavenge) that returns the 274 // object size. 275 class HeapWordImpl; // Opaque, never defined. 276 typedef HeapWordImpl* HeapWord; 277 278 // Analogous opaque struct for metadata allocated from metaspaces. 279 class MetaWordImpl; // Opaque, never defined. 280 typedef MetaWordImpl* MetaWord; 281 282 // HeapWordSize must be 2^LogHeapWordSize. 283 const int HeapWordSize = sizeof(HeapWord); 284 #ifdef _LP64 285 const int LogHeapWordSize = 3; 286 #else 287 const int LogHeapWordSize = 2; 288 #endif 289 const int HeapWordsPerLong = BytesPerLong / HeapWordSize; 290 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize; 291 292 // The minimum number of native machine words necessary to contain "byte_size" 293 // bytes. 294 inline size_t heap_word_size(size_t byte_size) { 295 return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize; 296 } 297 298 inline jfloat jfloat_cast(jint x); 299 inline jdouble jdouble_cast(jlong x); 300 301 //------------------------------------------- 302 // Constant for jlong (standardized by C++11) 303 304 // Build a 64bit integer constant 305 #define CONST64(x) (x ## LL) 306 #define UCONST64(x) (x ## ULL) 307 308 const jlong min_jlong = CONST64(0x8000000000000000); 309 const jlong max_jlong = CONST64(0x7fffffffffffffff); 310 311 //------------------------------------------- 312 // Constant for jdouble 313 const jlong min_jlongDouble = CONST64(0x0000000000000001); 314 const jdouble min_jdouble = jdouble_cast(min_jlongDouble); 315 const jlong max_jlongDouble = CONST64(0x7fefffffffffffff); 316 const jdouble max_jdouble = jdouble_cast(max_jlongDouble); 317 318 const size_t K = 1024; 319 const size_t M = K*K; 320 const size_t G = M*K; 321 const size_t HWperKB = K / sizeof(HeapWord); 322 323 // Constants for converting from a base unit to milli-base units. For 324 // example from seconds to milliseconds and microseconds 325 326 const int MILLIUNITS = 1000; // milli units per base unit 327 const int MICROUNITS = 1000000; // micro units per base unit 328 const int NANOUNITS = 1000000000; // nano units per base unit 329 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS; 330 331 const jlong NANOSECS_PER_SEC = CONST64(1000000000); 332 const jint NANOSECS_PER_MILLISEC = 1000000; 333 334 335 // Unit conversion functions 336 // The caller is responsible for considering overflow. 337 338 inline int64_t nanos_to_millis(int64_t nanos) { 339 return nanos / NANOUNITS_PER_MILLIUNIT; 340 } 341 inline int64_t millis_to_nanos(int64_t millis) { 342 return millis * NANOUNITS_PER_MILLIUNIT; 343 } 344 345 // Proper units routines try to maintain at least three significant digits. 346 // In worst case, it would print five significant digits with lower prefix. 347 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow, 348 // and therefore we need to be careful. 349 350 inline const char* proper_unit_for_byte_size(size_t s) { 351 #ifdef _LP64 352 if (s >= 100*G) { 353 return "G"; 354 } 355 #endif 356 if (s >= 100*M) { 357 return "M"; 358 } else if (s >= 100*K) { 359 return "K"; 360 } else { 361 return "B"; 362 } 363 } 364 365 template <class T> 366 inline T byte_size_in_proper_unit(T s) { 367 #ifdef _LP64 368 if (s >= 100*G) { 369 return (T)(s/G); 370 } 371 #endif 372 if (s >= 100*M) { 373 return (T)(s/M); 374 } else if (s >= 100*K) { 375 return (T)(s/K); 376 } else { 377 return s; 378 } 379 } 380 381 #define PROPERFMT SIZE_FORMAT "%s" 382 #define PROPERFMTARGS(s) byte_size_in_proper_unit(s), proper_unit_for_byte_size(s) 383 384 inline const char* exact_unit_for_byte_size(size_t s) { 385 #ifdef _LP64 386 if (s >= G && (s % G) == 0) { 387 return "G"; 388 } 389 #endif 390 if (s >= M && (s % M) == 0) { 391 return "M"; 392 } 393 if (s >= K && (s % K) == 0) { 394 return "K"; 395 } 396 return "B"; 397 } 398 399 inline size_t byte_size_in_exact_unit(size_t s) { 400 #ifdef _LP64 401 if (s >= G && (s % G) == 0) { 402 return s / G; 403 } 404 #endif 405 if (s >= M && (s % M) == 0) { 406 return s / M; 407 } 408 if (s >= K && (s % K) == 0) { 409 return s / K; 410 } 411 return s; 412 } 413 414 #define EXACTFMT SIZE_FORMAT "%s" 415 #define EXACTFMTARGS(s) byte_size_in_exact_unit(s), exact_unit_for_byte_size(s) 416 417 // Memory size transition formatting. 418 419 #define HEAP_CHANGE_FORMAT "%s: " SIZE_FORMAT "K(" SIZE_FORMAT "K)->" SIZE_FORMAT "K(" SIZE_FORMAT "K)" 420 421 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \ 422 (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K 423 424 //---------------------------------------------------------------------------------------------------- 425 // VM type definitions 426 427 // intx and uintx are the 'extended' int and 'extended' unsigned int types; 428 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform. 429 430 typedef intptr_t intx; 431 typedef uintptr_t uintx; 432 433 const intx min_intx = (intx)1 << (sizeof(intx)*BitsPerByte-1); 434 const intx max_intx = (uintx)min_intx - 1; 435 const uintx max_uintx = (uintx)-1; 436 437 // Table of values: 438 // sizeof intx 4 8 439 // min_intx 0x80000000 0x8000000000000000 440 // max_intx 0x7FFFFFFF 0x7FFFFFFFFFFFFFFF 441 // max_uintx 0xFFFFFFFF 0xFFFFFFFFFFFFFFFF 442 443 typedef unsigned int uint; NEEDS_CLEANUP 444 445 446 //---------------------------------------------------------------------------------------------------- 447 // Java type definitions 448 449 // All kinds of 'plain' byte addresses 450 typedef signed char s_char; 451 typedef unsigned char u_char; 452 typedef u_char* address; 453 typedef uintptr_t address_word; // unsigned integer which will hold a pointer 454 // except for some implementations of a C++ 455 // linkage pointer to function. Should never 456 // need one of those to be placed in this 457 // type anyway. 458 459 // Utility functions to "portably" (?) bit twiddle pointers 460 // Where portable means keep ANSI C++ compilers quiet 461 462 inline address set_address_bits(address x, int m) { return address(intptr_t(x) | m); } 463 inline address clear_address_bits(address x, int m) { return address(intptr_t(x) & ~m); } 464 465 // Utility functions to "portably" make cast to/from function pointers. 466 467 inline address_word mask_address_bits(address x, int m) { return address_word(x) & m; } 468 inline address_word castable_address(address x) { return address_word(x) ; } 469 inline address_word castable_address(void* x) { return address_word(x) ; } 470 471 // Pointer subtraction. 472 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have 473 // the range we might need to find differences from one end of the heap 474 // to the other. 475 // A typical use might be: 476 // if (pointer_delta(end(), top()) >= size) { 477 // // enough room for an object of size 478 // ... 479 // and then additions like 480 // ... top() + size ... 481 // are safe because we know that top() is at least size below end(). 482 inline size_t pointer_delta(const volatile void* left, 483 const volatile void* right, 484 size_t element_size) { 485 assert(left >= right, "avoid underflow - left: " PTR_FORMAT " right: " PTR_FORMAT, p2i(left), p2i(right)); 486 return (((uintptr_t) left) - ((uintptr_t) right)) / element_size; 487 } 488 489 // A version specialized for HeapWord*'s. 490 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) { 491 return pointer_delta(left, right, sizeof(HeapWord)); 492 } 493 // A version specialized for MetaWord*'s. 494 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) { 495 return pointer_delta(left, right, sizeof(MetaWord)); 496 } 497 498 // 499 // ANSI C++ does not allow casting from one pointer type to a function pointer 500 // directly without at best a warning. This macro accomplishes it silently 501 // In every case that is present at this point the value be cast is a pointer 502 // to a C linkage function. In some case the type used for the cast reflects 503 // that linkage and a picky compiler would not complain. In other cases because 504 // there is no convenient place to place a typedef with extern C linkage (i.e 505 // a platform dependent header file) it doesn't. At this point no compiler seems 506 // picky enough to catch these instances (which are few). It is possible that 507 // using templates could fix these for all cases. This use of templates is likely 508 // so far from the middle of the road that it is likely to be problematic in 509 // many C++ compilers. 510 // 511 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value)) 512 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((address_word)(func_ptr))) 513 514 // In many places we've added C-style casts to silence compiler 515 // warnings, for example when truncating a size_t to an int when we 516 // know the size_t is a small struct. Such casts are risky because 517 // they effectively disable useful compiler warnings. We can make our 518 // lives safer with this function, which ensures that any cast is 519 // reversible without loss of information. It doesn't check 520 // everything: it isn't intended to make sure that pointer types are 521 // compatible, for example. 522 template <typename T2, typename T1> 523 T2 checked_cast(T1 thing) { 524 T2 result = static_cast<T2>(thing); 525 assert(static_cast<T1>(result) == thing, "must be"); 526 return result; 527 } 528 529 // Need the correct linkage to call qsort without warnings 530 extern "C" { 531 typedef int (*_sort_Fn)(const void *, const void *); 532 } 533 534 // Additional Java basic types 535 536 typedef uint8_t jubyte; 537 typedef uint16_t jushort; 538 typedef uint32_t juint; 539 typedef uint64_t julong; 540 541 // Unsigned byte types for os and stream.hpp 542 543 // Unsigned one, two, four and eight byte quantities used for describing 544 // the .class file format. See JVM book chapter 4. 545 546 typedef jubyte u1; 547 typedef jushort u2; 548 typedef juint u4; 549 typedef julong u8; 550 551 const jubyte max_jubyte = (jubyte)-1; // 0xFF largest jubyte 552 const jushort max_jushort = (jushort)-1; // 0xFFFF largest jushort 553 const juint max_juint = (juint)-1; // 0xFFFFFFFF largest juint 554 const julong max_julong = (julong)-1; // 0xFF....FF largest julong 555 556 typedef jbyte s1; 557 typedef jshort s2; 558 typedef jint s4; 559 typedef jlong s8; 560 561 const jbyte min_jbyte = -(1 << 7); // smallest jbyte 562 const jbyte max_jbyte = (1 << 7) - 1; // largest jbyte 563 const jshort min_jshort = -(1 << 15); // smallest jshort 564 const jshort max_jshort = (1 << 15) - 1; // largest jshort 565 566 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint 567 const jint max_jint = (juint)min_jint - 1; // 0x7FFFFFFF == largest jint 568 569 const jint min_jintFloat = (jint)(0x00000001); 570 const jfloat min_jfloat = jfloat_cast(min_jintFloat); 571 const jint max_jintFloat = (jint)(0x7f7fffff); 572 const jfloat max_jfloat = jfloat_cast(max_jintFloat); 573 574 //---------------------------------------------------------------------------------------------------- 575 // JVM spec restrictions 576 577 const int max_method_code_size = 64*K - 1; // JVM spec, 2nd ed. section 4.8.1 (p.134) 578 579 //---------------------------------------------------------------------------------------------------- 580 // old CDS options 581 extern bool DumpSharedSpaces; 582 extern bool DynamicDumpSharedSpaces; 583 extern bool RequireSharedSpaces; 584 extern "C" { 585 // Make sure UseSharedSpaces is accessible to the serviceability agent. 586 extern JNIEXPORT jboolean UseSharedSpaces; 587 } 588 589 //---------------------------------------------------------------------------------------------------- 590 // Object alignment, in units of HeapWords. 591 // 592 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and 593 // reference fields can be naturally aligned. 594 595 extern int MinObjAlignment; 596 extern int MinObjAlignmentInBytes; 597 extern int MinObjAlignmentInBytesMask; 598 599 extern int LogMinObjAlignment; 600 extern int LogMinObjAlignmentInBytes; 601 602 const int LogKlassAlignmentInBytes = 3; 603 const int LogKlassAlignment = LogKlassAlignmentInBytes - LogHeapWordSize; 604 const int KlassAlignmentInBytes = 1 << LogKlassAlignmentInBytes; 605 const int KlassAlignment = KlassAlignmentInBytes / HeapWordSize; 606 607 // Maximal size of heap where unscaled compression can be used. Also upper bound 608 // for heap placement: 4GB. 609 const uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1); 610 // Maximal size of heap where compressed oops can be used. Also upper bound for heap 611 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes. 612 extern uint64_t OopEncodingHeapMax; 613 614 // Maximal size of compressed class space. Above this limit compression is not possible. 615 // Also upper bound for placement of zero based class space. (Class space is further limited 616 // to be < 3G, see arguments.cpp.) 617 const uint64_t KlassEncodingMetaspaceMax = (uint64_t(max_juint) + 1) << LogKlassAlignmentInBytes; 618 619 // Machine dependent stuff 620 621 // The maximum size of the code cache. Can be overridden by targets. 622 #define CODE_CACHE_SIZE_LIMIT (2*G) 623 // Allow targets to reduce the default size of the code cache. 624 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT 625 626 #include CPU_HEADER(globalDefinitions) 627 628 // To assure the IRIW property on processors that are not multiple copy 629 // atomic, sync instructions must be issued between volatile reads to 630 // assure their ordering, instead of after volatile stores. 631 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models" 632 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge) 633 #ifdef CPU_MULTI_COPY_ATOMIC 634 // Not needed. 635 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false; 636 #else 637 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment. 638 // Final decision is subject to JEP 188: Java Memory Model Update. 639 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false); 640 #endif 641 642 // The expected size in bytes of a cache line, used to pad data structures. 643 #ifndef DEFAULT_CACHE_LINE_SIZE 644 #error "Platform should define DEFAULT_CACHE_LINE_SIZE" 645 #endif 646 647 648 //---------------------------------------------------------------------------------------------------- 649 // Utility macros for compilers 650 // used to silence compiler warnings 651 652 #define Unused_Variable(var) var 653 654 655 //---------------------------------------------------------------------------------------------------- 656 // Miscellaneous 657 658 // 6302670 Eliminate Hotspot __fabsf dependency 659 // All fabs() callers should call this function instead, which will implicitly 660 // convert the operand to double, avoiding a dependency on __fabsf which 661 // doesn't exist in early versions of Solaris 8. 662 inline double fabsd(double value) { 663 return fabs(value); 664 } 665 666 // Returns numerator/denominator as percentage value from 0 to 100. If denominator 667 // is zero, return 0.0. 668 template<typename T> 669 inline double percent_of(T numerator, T denominator) { 670 return denominator != 0 ? (double)numerator / denominator * 100.0 : 0.0; 671 } 672 673 //---------------------------------------------------------------------------------------------------- 674 // Special casts 675 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern 676 typedef union { 677 jfloat f; 678 jint i; 679 } FloatIntConv; 680 681 typedef union { 682 jdouble d; 683 jlong l; 684 julong ul; 685 } DoubleLongConv; 686 687 inline jint jint_cast (jfloat x) { return ((FloatIntConv*)&x)->i; } 688 inline jfloat jfloat_cast (jint x) { return ((FloatIntConv*)&x)->f; } 689 690 inline jlong jlong_cast (jdouble x) { return ((DoubleLongConv*)&x)->l; } 691 inline julong julong_cast (jdouble x) { return ((DoubleLongConv*)&x)->ul; } 692 inline jdouble jdouble_cast (jlong x) { return ((DoubleLongConv*)&x)->d; } 693 694 inline jint low (jlong value) { return jint(value); } 695 inline jint high(jlong value) { return jint(value >> 32); } 696 697 // the fancy casts are a hopefully portable way 698 // to do unsigned 32 to 64 bit type conversion 699 inline void set_low (jlong* value, jint low ) { *value &= (jlong)0xffffffff << 32; 700 *value |= (jlong)(julong)(juint)low; } 701 702 inline void set_high(jlong* value, jint high) { *value &= (jlong)(julong)(juint)0xffffffff; 703 *value |= (jlong)high << 32; } 704 705 inline jlong jlong_from(jint h, jint l) { 706 jlong result = 0; // initialization to avoid warning 707 set_high(&result, h); 708 set_low(&result, l); 709 return result; 710 } 711 712 union jlong_accessor { 713 jint words[2]; 714 jlong long_value; 715 }; 716 717 void basic_types_init(); // cannot define here; uses assert 718 719 720 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java 721 enum BasicType { 722 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS. 723 T_BOOLEAN = JVM_T_BOOLEAN, 724 T_CHAR = JVM_T_CHAR, 725 T_FLOAT = JVM_T_FLOAT, 726 T_DOUBLE = JVM_T_DOUBLE, 727 T_BYTE = JVM_T_BYTE, 728 T_SHORT = JVM_T_SHORT, 729 T_INT = JVM_T_INT, 730 T_LONG = JVM_T_LONG, 731 // The remaining values are not part of any standard. 732 // T_OBJECT and T_VOID denote two more semantic choices 733 // for method return values. 734 // T_OBJECT and T_ARRAY describe signature syntax. 735 // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe 736 // internal references within the JVM as if they were Java 737 // types in their own right. 738 T_OBJECT = 12, 739 T_ARRAY = 13, 740 T_VOID = 14, 741 T_ADDRESS = 15, 742 T_NARROWOOP = 16, 743 T_METADATA = 17, 744 T_NARROWKLASS = 18, 745 T_CONFLICT = 19, // for stack value type with conflicting contents 746 T_ILLEGAL = 99 747 }; 748 749 #define SIGNATURE_TYPES_DO(F, N) \ 750 F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N) \ 751 F(JVM_SIGNATURE_CHAR, T_CHAR, N) \ 752 F(JVM_SIGNATURE_FLOAT, T_FLOAT, N) \ 753 F(JVM_SIGNATURE_DOUBLE, T_DOUBLE, N) \ 754 F(JVM_SIGNATURE_BYTE, T_BYTE, N) \ 755 F(JVM_SIGNATURE_SHORT, T_SHORT, N) \ 756 F(JVM_SIGNATURE_INT, T_INT, N) \ 757 F(JVM_SIGNATURE_LONG, T_LONG, N) \ 758 F(JVM_SIGNATURE_CLASS, T_OBJECT, N) \ 759 F(JVM_SIGNATURE_ARRAY, T_ARRAY, N) \ 760 F(JVM_SIGNATURE_VOID, T_VOID, N) \ 761 /*end*/ 762 763 inline bool is_java_type(BasicType t) { 764 return T_BOOLEAN <= t && t <= T_VOID; 765 } 766 767 inline bool is_java_primitive(BasicType t) { 768 return T_BOOLEAN <= t && t <= T_LONG; 769 } 770 771 inline bool is_subword_type(BasicType t) { 772 // these guys are processed exactly like T_INT in calling sequences: 773 return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT); 774 } 775 776 inline bool is_signed_subword_type(BasicType t) { 777 return (t == T_BYTE || t == T_SHORT); 778 } 779 780 inline bool is_unsigned_subword_type(BasicType t) { 781 return (t == T_BOOLEAN || t == T_CHAR); 782 } 783 784 inline bool is_double_word_type(BasicType t) { 785 return (t == T_DOUBLE || t == T_LONG); 786 } 787 788 inline bool is_reference_type(BasicType t, bool include_narrow_oop = false) { 789 return (t == T_OBJECT || t == T_ARRAY || (include_narrow_oop && t == T_NARROWOOP)); 790 } 791 792 inline bool is_integral_type(BasicType t) { 793 return is_subword_type(t) || t == T_INT || t == T_LONG; 794 } 795 796 inline bool is_non_subword_integral_type(BasicType t) { 797 return t == T_INT || t == T_LONG; 798 } 799 800 inline bool is_floating_point_type(BasicType t) { 801 return (t == T_FLOAT || t == T_DOUBLE); 802 } 803 804 extern char type2char_tab[T_CONFLICT+1]; // Map a BasicType to a jchar 805 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; } 806 extern int type2size[T_CONFLICT+1]; // Map BasicType to result stack elements 807 extern const char* type2name_tab[T_CONFLICT+1]; // Map a BasicType to a char* 808 extern BasicType name2type(const char* name); 809 810 const char* type2name(BasicType t); 811 812 inline jlong max_signed_integer(BasicType bt) { 813 if (bt == T_INT) { 814 return max_jint; 815 } 816 assert(bt == T_LONG, "unsupported"); 817 return max_jlong; 818 } 819 820 inline jlong min_signed_integer(BasicType bt) { 821 if (bt == T_INT) { 822 return min_jint; 823 } 824 assert(bt == T_LONG, "unsupported"); 825 return min_jlong; 826 } 827 828 // Auxiliary math routines 829 // least common multiple 830 extern size_t lcm(size_t a, size_t b); 831 832 833 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java 834 enum BasicTypeSize { 835 T_BOOLEAN_size = 1, 836 T_CHAR_size = 1, 837 T_FLOAT_size = 1, 838 T_DOUBLE_size = 2, 839 T_BYTE_size = 1, 840 T_SHORT_size = 1, 841 T_INT_size = 1, 842 T_LONG_size = 2, 843 T_OBJECT_size = 1, 844 T_ARRAY_size = 1, 845 T_NARROWOOP_size = 1, 846 T_NARROWKLASS_size = 1, 847 T_VOID_size = 0 848 }; 849 850 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc. 851 inline int parameter_type_word_count(BasicType t) { 852 if (is_double_word_type(t)) return 2; 853 assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please"); 854 assert(type2size[t] == 1, "must be"); 855 return 1; 856 } 857 858 // maps a BasicType to its instance field storage type: 859 // all sub-word integral types are widened to T_INT 860 extern BasicType type2field[T_CONFLICT+1]; 861 extern BasicType type2wfield[T_CONFLICT+1]; 862 863 864 // size in bytes 865 enum ArrayElementSize { 866 T_BOOLEAN_aelem_bytes = 1, 867 T_CHAR_aelem_bytes = 2, 868 T_FLOAT_aelem_bytes = 4, 869 T_DOUBLE_aelem_bytes = 8, 870 T_BYTE_aelem_bytes = 1, 871 T_SHORT_aelem_bytes = 2, 872 T_INT_aelem_bytes = 4, 873 T_LONG_aelem_bytes = 8, 874 #ifdef _LP64 875 T_OBJECT_aelem_bytes = 8, 876 T_ARRAY_aelem_bytes = 8, 877 #else 878 T_OBJECT_aelem_bytes = 4, 879 T_ARRAY_aelem_bytes = 4, 880 #endif 881 T_NARROWOOP_aelem_bytes = 4, 882 T_NARROWKLASS_aelem_bytes = 4, 883 T_VOID_aelem_bytes = 0 884 }; 885 886 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element 887 #ifdef ASSERT 888 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts 889 #else 890 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; } 891 #endif 892 893 inline bool same_type_or_subword_size(BasicType t1, BasicType t2) { 894 return (t1 == t2) || (is_subword_type(t1) && type2aelembytes(t1) == type2aelembytes(t2)); 895 } 896 897 // JavaValue serves as a container for arbitrary Java values. 898 899 class JavaValue { 900 901 public: 902 typedef union JavaCallValue { 903 jfloat f; 904 jdouble d; 905 jint i; 906 jlong l; 907 jobject h; 908 oopDesc* o; 909 } JavaCallValue; 910 911 private: 912 BasicType _type; 913 JavaCallValue _value; 914 915 public: 916 JavaValue(BasicType t = T_ILLEGAL) { _type = t; } 917 918 JavaValue(jfloat value) { 919 _type = T_FLOAT; 920 _value.f = value; 921 } 922 923 JavaValue(jdouble value) { 924 _type = T_DOUBLE; 925 _value.d = value; 926 } 927 928 jfloat get_jfloat() const { return _value.f; } 929 jdouble get_jdouble() const { return _value.d; } 930 jint get_jint() const { return _value.i; } 931 jlong get_jlong() const { return _value.l; } 932 jobject get_jobject() const { return _value.h; } 933 oopDesc* get_oop() const { return _value.o; } 934 JavaCallValue* get_value_addr() { return &_value; } 935 BasicType get_type() const { return _type; } 936 937 void set_jfloat(jfloat f) { _value.f = f;} 938 void set_jdouble(jdouble d) { _value.d = d;} 939 void set_jint(jint i) { _value.i = i;} 940 void set_jlong(jlong l) { _value.l = l;} 941 void set_jobject(jobject h) { _value.h = h;} 942 void set_oop(oopDesc* o) { _value.o = o;} 943 void set_type(BasicType t) { _type = t; } 944 945 jboolean get_jboolean() const { return (jboolean) (_value.i);} 946 jbyte get_jbyte() const { return (jbyte) (_value.i);} 947 jchar get_jchar() const { return (jchar) (_value.i);} 948 jshort get_jshort() const { return (jshort) (_value.i);} 949 950 }; 951 952 953 // TosState describes the top-of-stack state before and after the execution of 954 // a bytecode or method. The top-of-stack value may be cached in one or more CPU 955 // registers. The TosState corresponds to the 'machine representation' of this cached 956 // value. There's 4 states corresponding to the JAVA types int, long, float & double 957 // as well as a 5th state in case the top-of-stack value is actually on the top 958 // of stack (in memory) and thus not cached. The atos state corresponds to the itos 959 // state when it comes to machine representation but is used separately for (oop) 960 // type specific operations (e.g. verification code). 961 962 enum TosState { // describes the tos cache contents 963 btos = 0, // byte, bool tos cached 964 ztos = 1, // byte, bool tos cached 965 ctos = 2, // char tos cached 966 stos = 3, // short tos cached 967 itos = 4, // int tos cached 968 ltos = 5, // long tos cached 969 ftos = 6, // float tos cached 970 dtos = 7, // double tos cached 971 atos = 8, // object cached 972 vtos = 9, // tos not cached 973 number_of_states, 974 ilgl // illegal state: should not occur 975 }; 976 977 978 inline TosState as_TosState(BasicType type) { 979 switch (type) { 980 case T_BYTE : return btos; 981 case T_BOOLEAN: return ztos; 982 case T_CHAR : return ctos; 983 case T_SHORT : return stos; 984 case T_INT : return itos; 985 case T_LONG : return ltos; 986 case T_FLOAT : return ftos; 987 case T_DOUBLE : return dtos; 988 case T_VOID : return vtos; 989 case T_ARRAY : // fall through 990 case T_OBJECT : return atos; 991 default : return ilgl; 992 } 993 } 994 995 inline BasicType as_BasicType(TosState state) { 996 switch (state) { 997 case btos : return T_BYTE; 998 case ztos : return T_BOOLEAN; 999 case ctos : return T_CHAR; 1000 case stos : return T_SHORT; 1001 case itos : return T_INT; 1002 case ltos : return T_LONG; 1003 case ftos : return T_FLOAT; 1004 case dtos : return T_DOUBLE; 1005 case atos : return T_OBJECT; 1006 case vtos : return T_VOID; 1007 default : return T_ILLEGAL; 1008 } 1009 } 1010 1011 1012 // Helper function to convert BasicType info into TosState 1013 // Note: Cannot define here as it uses global constant at the time being. 1014 TosState as_TosState(BasicType type); 1015 1016 1017 // JavaThreadState keeps track of which part of the code a thread is executing in. This 1018 // information is needed by the safepoint code. 1019 // 1020 // There are 4 essential states: 1021 // 1022 // _thread_new : Just started, but not executed init. code yet (most likely still in OS init code) 1023 // _thread_in_native : In native code. This is a safepoint region, since all oops will be in jobject handles 1024 // _thread_in_vm : Executing in the vm 1025 // _thread_in_Java : Executing either interpreted or compiled Java code (or could be in a stub) 1026 // 1027 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in 1028 // a transition from one state to another. These extra states makes it possible for the safepoint code to 1029 // handle certain thread_states without having to suspend the thread - making the safepoint code faster. 1030 // 1031 // Given a state, the xxxx_trans state can always be found by adding 1. 1032 // 1033 enum JavaThreadState { 1034 _thread_uninitialized = 0, // should never happen (missing initialization) 1035 _thread_new = 2, // just starting up, i.e., in process of being initialized 1036 _thread_new_trans = 3, // corresponding transition state (not used, included for completeness) 1037 _thread_in_native = 4, // running in native code 1038 _thread_in_native_trans = 5, // corresponding transition state 1039 _thread_in_vm = 6, // running in VM 1040 _thread_in_vm_trans = 7, // corresponding transition state 1041 _thread_in_Java = 8, // running in Java or in stub code 1042 _thread_in_Java_trans = 9, // corresponding transition state (not used, included for completeness) 1043 _thread_blocked = 10, // blocked in vm 1044 _thread_blocked_trans = 11, // corresponding transition state 1045 _thread_max_state = 12 // maximum thread state+1 - used for statistics allocation 1046 }; 1047 1048 enum LockingMode { 1049 // Use only heavy monitors for locking 1050 LM_MONITOR = 0, 1051 // Legacy stack-locking, with monitors as 2nd tier 1052 LM_LEGACY = 1, 1053 // New lightweight locking, with monitors as 2nd tier 1054 LM_LIGHTWEIGHT = 2 1055 }; 1056 1057 //---------------------------------------------------------------------------------------------------- 1058 // Special constants for debugging 1059 1060 const jint badInt = -3; // generic "bad int" value 1061 const intptr_t badAddressVal = -2; // generic "bad address" value 1062 const intptr_t badOopVal = -1; // generic "bad oop" value 1063 const intptr_t badHeapOopVal = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC 1064 const int badStackSegVal = 0xCA; // value used to zap stack segments 1065 const int badHandleValue = 0xBC; // value used to zap vm handle area 1066 const int badResourceValue = 0xAB; // value used to zap resource area 1067 const int freeBlockPad = 0xBA; // value used to pad freed blocks. 1068 const int uninitBlockPad = 0xF1; // value used to zap newly malloc'd blocks. 1069 const juint uninitMetaWordVal= 0xf7f7f7f7; // value used to zap newly allocated metachunk 1070 const juint badHeapWordVal = 0xBAADBABE; // value used to zap heap after GC 1071 const juint badMetaWordVal = 0xBAADFADE; // value used to zap metadata heap after GC 1072 const int badCodeHeapNewVal= 0xCC; // value used to zap Code heap at allocation 1073 const int badCodeHeapFreeVal = 0xDD; // value used to zap Code heap at deallocation 1074 1075 1076 // (These must be implemented as #defines because C++ compilers are 1077 // not obligated to inline non-integral constants!) 1078 #define badAddress ((address)::badAddressVal) 1079 #define badHeapWord (::badHeapWordVal) 1080 1081 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit) 1082 #define TASKQUEUE_SIZE (NOT_LP64(1<<14) LP64_ONLY(1<<17)) 1083 1084 //---------------------------------------------------------------------------------------------------- 1085 // Utility functions for bitfield manipulations 1086 1087 const intptr_t AllBits = ~0; // all bits set in a word 1088 const intptr_t NoBits = 0; // no bits set in a word 1089 const jlong NoLongBits = 0; // no bits set in a long 1090 const intptr_t OneBit = 1; // only right_most bit set in a word 1091 1092 // get a word with the n.th or the right-most or left-most n bits set 1093 // (note: #define used only so that they can be used in enum constant definitions) 1094 #define nth_bit(n) (((n) >= BitsPerWord) ? 0 : (OneBit << (n))) 1095 #define right_n_bits(n) (nth_bit(n) - 1) 1096 1097 // bit-operations using a mask m 1098 inline void set_bits (intptr_t& x, intptr_t m) { x |= m; } 1099 inline void clear_bits (intptr_t& x, intptr_t m) { x &= ~m; } 1100 inline intptr_t mask_bits (intptr_t x, intptr_t m) { return x & m; } 1101 inline jlong mask_long_bits (jlong x, jlong m) { return x & m; } 1102 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; } 1103 1104 // bit-operations using the n.th bit 1105 inline void set_nth_bit(intptr_t& x, int n) { set_bits (x, nth_bit(n)); } 1106 inline void clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); } 1107 inline bool is_set_nth_bit(intptr_t x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; } 1108 1109 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!) 1110 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) { 1111 return mask_bits(x >> start_bit_no, right_n_bits(field_length)); 1112 } 1113 1114 1115 //---------------------------------------------------------------------------------------------------- 1116 // Utility functions for integers 1117 1118 // Avoid use of global min/max macros which may cause unwanted double 1119 // evaluation of arguments. 1120 #ifdef max 1121 #undef max 1122 #endif 1123 1124 #ifdef min 1125 #undef min 1126 #endif 1127 1128 // It is necessary to use templates here. Having normal overloaded 1129 // functions does not work because it is necessary to provide both 32- 1130 // and 64-bit overloaded functions, which does not work, and having 1131 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L) 1132 // will be even more error-prone than macros. 1133 template<class T> constexpr T MAX2(T a, T b) { return (a > b) ? a : b; } 1134 template<class T> constexpr T MIN2(T a, T b) { return (a < b) ? a : b; } 1135 template<class T> constexpr T MAX3(T a, T b, T c) { return MAX2(MAX2(a, b), c); } 1136 template<class T> constexpr T MIN3(T a, T b, T c) { return MIN2(MIN2(a, b), c); } 1137 template<class T> constexpr T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); } 1138 template<class T> constexpr T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); } 1139 1140 template<class T> inline T ABS(T x) { return (x > 0) ? x : -x; } 1141 1142 // Return the given value clamped to the range [min ... max] 1143 template<typename T> 1144 inline T clamp(T value, T min, T max) { 1145 assert(min <= max, "must be"); 1146 return MIN2(MAX2(value, min), max); 1147 } 1148 1149 inline bool is_odd (intx x) { return x & 1; } 1150 inline bool is_even(intx x) { return !is_odd(x); } 1151 1152 // abs methods which cannot overflow and so are well-defined across 1153 // the entire domain of integer types. 1154 static inline unsigned int uabs(unsigned int n) { 1155 union { 1156 unsigned int result; 1157 int value; 1158 }; 1159 result = n; 1160 if (value < 0) result = 0-result; 1161 return result; 1162 } 1163 static inline julong uabs(julong n) { 1164 union { 1165 julong result; 1166 jlong value; 1167 }; 1168 result = n; 1169 if (value < 0) result = 0-result; 1170 return result; 1171 } 1172 static inline julong uabs(jlong n) { return uabs((julong)n); } 1173 static inline unsigned int uabs(int n) { return uabs((unsigned int)n); } 1174 1175 // "to" should be greater than "from." 1176 inline intx byte_size(void* from, void* to) { 1177 return (address)to - (address)from; 1178 } 1179 1180 // Pack and extract shorts to/from ints: 1181 1182 inline u2 extract_low_short_from_int(u4 x) { 1183 return u2(x & 0xffff); 1184 } 1185 1186 inline u2 extract_high_short_from_int(u4 x) { 1187 return u2((x >> 16) & 0xffff); 1188 } 1189 1190 inline int build_int_from_shorts( u2 low, u2 high ) { 1191 return ((int)((unsigned int)high << 16) | (unsigned int)low); 1192 } 1193 1194 // swap a & b 1195 template<class T> static void swap(T& a, T& b) { 1196 T tmp = a; 1197 a = b; 1198 b = tmp; 1199 } 1200 1201 // array_size_impl is a function that takes a reference to T[N] and 1202 // returns a reference to char[N]. It is not ODR-used, so not defined. 1203 template<typename T, size_t N> char (&array_size_impl(T (&)[N]))[N]; 1204 1205 #define ARRAY_SIZE(array) sizeof(array_size_impl(array)) 1206 1207 //---------------------------------------------------------------------------------------------------- 1208 // Sum and product which can never overflow: they wrap, just like the 1209 // Java operations. Note that we don't intend these to be used for 1210 // general-purpose arithmetic: their purpose is to emulate Java 1211 // operations. 1212 1213 // The goal of this code to avoid undefined or implementation-defined 1214 // behavior. The use of an lvalue to reference cast is explicitly 1215 // permitted by Lvalues and rvalues [basic.lval]. [Section 3.10 Para 1216 // 15 in C++03] 1217 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE) \ 1218 inline TYPE NAME (TYPE in1, TYPE in2) { \ 1219 UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \ 1220 ures OP ## = static_cast<UNSIGNED_TYPE>(in2); \ 1221 return reinterpret_cast<TYPE&>(ures); \ 1222 } 1223 1224 JAVA_INTEGER_OP(+, java_add, jint, juint) 1225 JAVA_INTEGER_OP(-, java_subtract, jint, juint) 1226 JAVA_INTEGER_OP(*, java_multiply, jint, juint) 1227 JAVA_INTEGER_OP(+, java_add, jlong, julong) 1228 JAVA_INTEGER_OP(-, java_subtract, jlong, julong) 1229 JAVA_INTEGER_OP(*, java_multiply, jlong, julong) 1230 1231 inline jint java_negate(jint v) { return java_subtract((jint) 0, v); } 1232 inline jlong java_negate(jlong v) { return java_subtract((jlong)0, v); } 1233 1234 #undef JAVA_INTEGER_OP 1235 1236 // Provide integer shift operations with Java semantics. No overflow 1237 // issues - left shifts simply discard shifted out bits. No undefined 1238 // behavior for large or negative shift quantities; instead the actual 1239 // shift distance is the argument modulo the lhs value's size in bits. 1240 // No undefined or implementation defined behavior for shifting negative 1241 // values; left shift discards bits, right shift sign extends. We use 1242 // the same safe conversion technique as above for java_add and friends. 1243 #define JAVA_INTEGER_SHIFT_OP(OP, NAME, TYPE, XTYPE) \ 1244 inline TYPE NAME (TYPE lhs, jint rhs) { \ 1245 const uint rhs_mask = (sizeof(TYPE) * 8) - 1; \ 1246 STATIC_ASSERT(rhs_mask == 31 || rhs_mask == 63); \ 1247 XTYPE xres = static_cast<XTYPE>(lhs); \ 1248 xres OP ## = (rhs & rhs_mask); \ 1249 return reinterpret_cast<TYPE&>(xres); \ 1250 } 1251 1252 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jint, juint) 1253 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jlong, julong) 1254 1255 // For signed shift right, assume C++ implementation >> sign extends. 1256 // 1257 // C++14 5.8/3: In the description of "E1 >> E2" it says "If E1 has a signed type 1258 // and a negative value, the resulting value is implementation-defined." 1259 // 1260 // However, C++20 7.6.7/3 further defines integral arithmetic, as part of 1261 // requiring two's-complement behavior. 1262 // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0907r3.html 1263 // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1236r1.html 1264 // The corresponding C++20 text is "Right-shift on signed integral types is an 1265 // arithmetic right shift, which performs sign-extension." 1266 // 1267 // As discussed in the two's complement proposal, all known modern C++ compilers 1268 // already behave that way. And it is unlikely any would go off and do something 1269 // different now, with C++20 tightening things up. 1270 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jint, jint) 1271 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jlong, jlong) 1272 // For >>> use C++ unsigned >>. 1273 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jint, juint) 1274 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jlong, julong) 1275 1276 #undef JAVA_INTEGER_SHIFT_OP 1277 1278 //---------------------------------------------------------------------------------------------------- 1279 // The goal of this code is to provide saturating operations for int/uint. 1280 // Checks overflow conditions and saturates the result to min_jint/max_jint. 1281 #define SATURATED_INTEGER_OP(OP, NAME, TYPE1, TYPE2) \ 1282 inline int NAME (TYPE1 in1, TYPE2 in2) { \ 1283 jlong res = static_cast<jlong>(in1); \ 1284 res OP ## = static_cast<jlong>(in2); \ 1285 if (res > max_jint) { \ 1286 res = max_jint; \ 1287 } else if (res < min_jint) { \ 1288 res = min_jint; \ 1289 } \ 1290 return static_cast<int>(res); \ 1291 } 1292 1293 SATURATED_INTEGER_OP(+, saturated_add, int, int) 1294 SATURATED_INTEGER_OP(+, saturated_add, int, uint) 1295 SATURATED_INTEGER_OP(+, saturated_add, uint, int) 1296 SATURATED_INTEGER_OP(+, saturated_add, uint, uint) 1297 1298 #undef SATURATED_INTEGER_OP 1299 1300 // Taken from rom section 8-2 of Henry S. Warren, Jr., Hacker's Delight (2nd ed.) (Addison Wesley, 2013), 173-174. 1301 inline uint64_t multiply_high_unsigned(const uint64_t x, const uint64_t y) { 1302 const uint64_t x1 = x >> 32u; 1303 const uint64_t x2 = x & 0xFFFFFFFF; 1304 const uint64_t y1 = y >> 32u; 1305 const uint64_t y2 = y & 0xFFFFFFFF; 1306 const uint64_t z2 = x2 * y2; 1307 const uint64_t t = x1 * y2 + (z2 >> 32u); 1308 uint64_t z1 = t & 0xFFFFFFFF; 1309 const uint64_t z0 = t >> 32u; 1310 z1 += x2 * y1; 1311 1312 return x1 * y1 + z0 + (z1 >> 32u); 1313 } 1314 1315 // Taken from java.lang.Math::multiplyHigh which uses the technique from section 8-2 of Henry S. Warren, Jr., 1316 // Hacker's Delight (2nd ed.) (Addison Wesley, 2013), 173-174 but adapted for signed longs. 1317 inline int64_t multiply_high_signed(const int64_t x, const int64_t y) { 1318 const jlong x1 = java_shift_right((jlong)x, 32); 1319 const jlong x2 = x & 0xFFFFFFFF; 1320 const jlong y1 = java_shift_right((jlong)y, 32); 1321 const jlong y2 = y & 0xFFFFFFFF; 1322 1323 const uint64_t z2 = (uint64_t)x2 * y2; 1324 const int64_t t = x1 * y2 + (z2 >> 32u); // Unsigned shift 1325 int64_t z1 = t & 0xFFFFFFFF; 1326 const int64_t z0 = java_shift_right((jlong)t, 32); 1327 z1 += x2 * y1; 1328 1329 return x1 * y1 + z0 + java_shift_right((jlong)z1, 32); 1330 } 1331 1332 // Dereference vptr 1333 // All C++ compilers that we know of have the vtbl pointer in the first 1334 // word. If there are exceptions, this function needs to be made compiler 1335 // specific. 1336 static inline void* dereference_vptr(const void* addr) { 1337 return *(void**)addr; 1338 } 1339 1340 //---------------------------------------------------------------------------------------------------- 1341 // String type aliases used by command line flag declarations and 1342 // processing utilities. 1343 1344 typedef const char* ccstr; 1345 typedef const char* ccstrlist; // represents string arguments which accumulate 1346 1347 //---------------------------------------------------------------------------------------------------- 1348 // Default hash/equals functions used by ResourceHashtable 1349 1350 template<typename K> unsigned primitive_hash(const K& k) { 1351 unsigned hash = (unsigned)((uintptr_t)k); 1352 return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs 1353 } 1354 1355 template<typename K> bool primitive_equals(const K& k0, const K& k1) { 1356 return k0 == k1; 1357 } 1358 1359 //---------------------------------------------------------------------------------------------------- 1360 1361 // Allow use of C++ thread_local when approved - see JDK-8282469. 1362 #define APPROVED_CPP_THREAD_LOCAL thread_local 1363 1364 // Converts any type T to a reference type. 1365 template<typename T> 1366 std::add_rvalue_reference_t<T> declval() noexcept; 1367 1368 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP