1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_UTILITIES_GLOBALDEFINITIONS_HPP
26 #define SHARE_UTILITIES_GLOBALDEFINITIONS_HPP
27
28 #include "utilities/compilerWarnings.hpp"
29 #include "utilities/debug.hpp"
30 #include "utilities/forbiddenFunctions.hpp"
31 #include "utilities/macros.hpp"
32
33 // Get constants like JVM_T_CHAR and JVM_SIGNATURE_INT, before pulling in <jvm.h>.
34 #include "classfile_constants.h"
35
36 #include COMPILER_HEADER(utilities/globalDefinitions)
37
38 #include <cstddef>
39 #include <cstdint>
40 #include <limits>
41 #include <type_traits>
42
43 class oopDesc;
44
45 // Defaults for macros that might be defined per compiler.
46 #ifndef NOINLINE
47 #define NOINLINE
48 #endif
49 #ifndef ALWAYSINLINE
50 #define ALWAYSINLINE inline
51 #endif
52
53 #ifndef ATTRIBUTE_ALIGNED
54 #define ATTRIBUTE_ALIGNED(x) alignas(x)
55 #endif
56
57 #ifndef ATTRIBUTE_FLATTEN
58 #define ATTRIBUTE_FLATTEN
59 #endif
60
61 // These are #defines to selectively turn on/off the Print(Opto)Assembly
62 // capabilities. Choices should be led by a tradeoff between
63 // code size and improved supportability.
64 // if PRINT_ASSEMBLY then PRINT_ABSTRACT_ASSEMBLY must be true as well
65 // to have a fallback in case hsdis is not available.
66 #if defined(PRODUCT)
67 #define SUPPORT_ABSTRACT_ASSEMBLY
68 #define SUPPORT_ASSEMBLY
69 #undef SUPPORT_OPTO_ASSEMBLY // Can't activate. In PRODUCT, many dump methods are missing.
70 #undef SUPPORT_DATA_STRUCTS // Of limited use. In PRODUCT, many print methods are empty.
71 #else
72 #define SUPPORT_ABSTRACT_ASSEMBLY
73 #define SUPPORT_ASSEMBLY
74 #define SUPPORT_OPTO_ASSEMBLY
75 #define SUPPORT_DATA_STRUCTS
76 #endif
77 #if defined(SUPPORT_ASSEMBLY) && !defined(SUPPORT_ABSTRACT_ASSEMBLY)
78 #define SUPPORT_ABSTRACT_ASSEMBLY
79 #endif
80
81 // This file holds all globally used constants & types, class (forward)
82 // declarations and a few frequently used utility functions.
83
84 // Declare the named class to be noncopyable. This macro must be followed by
85 // a semi-colon. The macro provides deleted declarations for the class's copy
86 // constructor and assignment operator. Because these operations are deleted,
87 // they cannot be defined and potential callers will fail to compile.
88 #define NONCOPYABLE(C) C(C const&) = delete; C& operator=(C const&) = delete /* next token must be ; */
89
90
91 //----------------------------------------------------------------------------------------------------
92 // Printf-style formatters for fixed- and variable-width types as pointers and
93 // integers. These are derived from the definitions in inttypes.h. If the platform
94 // doesn't provide appropriate definitions, they should be provided in
95 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp)
96
97 // Guide to the suffixes used in the format specifiers for integers:
98 // - print the decimal value: 745565
99 // _X - print as hexadecimal, without leading 0s: 0x12345
100 // _X_0 - print as hexadecimal, with leading 0s: 0x00012345
101 // _W(w) - prints w sized string with the given value right
102 // adjusted. Use -w to print left adjusted.
103 // _0 - print as hexadecimal, with leading 0s, without 0x prefix: 0012345
104 //
105 // Note that the PTR format specifiers print using 0x with leading zeros,
106 // just like the _X_0 version for integers.
107
108 // Format 8-bit quantities.
109 #define INT8_FORMAT_X_0 "0x%02" PRIx8
110 #define UINT8_FORMAT_X_0 "0x%02" PRIx8
111
112 // Format 16-bit quantities.
113 #define INT16_FORMAT_X_0 "0x%04" PRIx16
114 #define UINT16_FORMAT_X_0 "0x%04" PRIx16
115
116 // Format 32-bit quantities.
117 #define INT32_FORMAT "%" PRId32
118 #define INT32_FORMAT_X "0x%" PRIx32
119 #define INT32_FORMAT_X_0 "0x%08" PRIx32
120 #define INT32_FORMAT_W(width) "%" #width PRId32
121 #define UINT32_FORMAT "%" PRIu32
122 #define UINT32_FORMAT_X "0x%" PRIx32
123 #define UINT32_FORMAT_X_0 "0x%08" PRIx32
124 #define UINT32_FORMAT_W(width) "%" #width PRIu32
125
126 // Format 64-bit quantities.
127 #define INT64_FORMAT "%" PRId64
128 #define INT64_PLUS_FORMAT "%+" PRId64
129 #define INT64_FORMAT_X "0x%" PRIx64
130 #define INT64_FORMAT_X_0 "0x%016" PRIx64
131 #define INT64_FORMAT_W(width) "%" #width PRId64
132 #define UINT64_FORMAT "%" PRIu64
133 #define UINT64_FORMAT_X "0x%" PRIx64
134 #define UINT64_FORMAT_X_0 "0x%016" PRIx64
135 #define UINT64_FORMAT_W(width) "%" #width PRIu64
136 #define UINT64_FORMAT_0 "%016" PRIx64
137
138 // Format jlong, if necessary
139 #ifndef JLONG_FORMAT
140 #define JLONG_FORMAT INT64_FORMAT
141 #endif
142 #ifndef JLONG_FORMAT_W
143 #define JLONG_FORMAT_W(width) INT64_FORMAT_W(width)
144 #endif
145 #ifndef JULONG_FORMAT
146 #define JULONG_FORMAT UINT64_FORMAT
147 #endif
148 #ifndef JULONG_FORMAT_X
149 #define JULONG_FORMAT_X UINT64_FORMAT_X
150 #endif
151
152 // Format pointers and padded integral values which change size between 32- and 64-bit.
153 #ifdef _LP64
154 #define INTPTR_FORMAT "0x%016" PRIxPTR
155 #define PTR_FORMAT "0x%016" PRIxPTR
156 #define UINTX_FORMAT_X_0 "0x%016" PRIxPTR
157 #define SIZE_FORMAT_X_0 "0x%016" PRIxPTR
158 #else // !_LP64
159 #define INTPTR_FORMAT "0x%08" PRIxPTR
160 #define PTR_FORMAT "0x%08" PRIxPTR
161 #define UINTX_FORMAT_X_0 "0x%08" PRIxPTR
162 #define SIZE_FORMAT_X_0 "0x%08" PRIxPTR
163 #endif // _LP64
164
165 // Convert pointer to intptr_t, for use in printing pointers.
166 inline intptr_t p2i(const volatile void* p) {
167 return (intptr_t) p;
168 }
169
170 // Convert pointer to uintptr_t
171 inline uintptr_t p2u(const volatile void* p) {
172 return (uintptr_t) p;
173 }
174
175 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false")
176
177 //----------------------------------------------------------------------------------------------------
178 // Constants
179
180 const int LogBytesPerShort = 1;
181 const int LogBytesPerInt = 2;
182 #ifdef _LP64
183 constexpr int LogBytesPerWord = 3;
184 #else
185 constexpr int LogBytesPerWord = 2;
186 #endif
187 const int LogBytesPerLong = 3;
188
189 const int BytesPerShort = 1 << LogBytesPerShort;
190 const int BytesPerInt = 1 << LogBytesPerInt;
191 const int BytesPerWord = 1 << LogBytesPerWord;
192 const int BytesPerLong = 1 << LogBytesPerLong;
193
194 constexpr int LogBitsPerByte = 3;
195 const int LogBitsPerShort = LogBitsPerByte + LogBytesPerShort;
196 const int LogBitsPerInt = LogBitsPerByte + LogBytesPerInt;
197 constexpr int LogBitsPerWord = LogBitsPerByte + LogBytesPerWord;
198 const int LogBitsPerLong = LogBitsPerByte + LogBytesPerLong;
199
200 const int BitsPerByte = 1 << LogBitsPerByte;
201 const int BitsPerShort = 1 << LogBitsPerShort;
202 const int BitsPerInt = 1 << LogBitsPerInt;
203 constexpr int BitsPerWord = 1 << LogBitsPerWord;
204 const int BitsPerLong = 1 << LogBitsPerLong;
205
206 const int WordAlignmentMask = (1 << LogBytesPerWord) - 1;
207 const int LongAlignmentMask = (1 << LogBytesPerLong) - 1;
208
209 const int oopSize = sizeof(char*); // Full-width oop
210 extern int heapOopSize; // Oop within a java object
211 const int wordSize = sizeof(char*);
212 const int longSize = sizeof(jlong);
213 const int jintSize = sizeof(jint);
214 const int size_tSize = sizeof(size_t);
215
216 const int BytesPerOop = BytesPerWord; // Full-width oop
217
218 extern int LogBytesPerHeapOop; // Oop within a java object
219 extern int LogBitsPerHeapOop;
220 extern int BytesPerHeapOop;
221 extern int BitsPerHeapOop;
222
223 const int BitsPerJavaInteger = 32;
224 const int BitsPerJavaLong = 64;
225 const int BitsPerSize_t = size_tSize * BitsPerByte;
226
227 // Size of a char[] needed to represent a jint as a string in decimal.
228 const int jintAsStringSize = 12;
229
230 // An opaque type, so that HeapWord* can be a generic pointer into the heap.
231 // We require that object sizes be measured in units of heap words (e.g.
232 // pointer-sized values), so that given HeapWord* hw,
233 // hw += oop(hw)->foo();
234 // works, where foo is a method (like size or scavenge) that returns the
235 // object size.
236 class HeapWordImpl; // Opaque, never defined.
237 typedef HeapWordImpl* HeapWord;
238
239 // Analogous opaque struct for metadata allocated from metaspaces.
240 class MetaWordImpl; // Opaque, never defined.
241 typedef MetaWordImpl* MetaWord;
242
243 // HeapWordSize must be 2^LogHeapWordSize.
244 const int HeapWordSize = sizeof(HeapWord);
245 #ifdef _LP64
246 const int LogHeapWordSize = 3;
247 #else
248 const int LogHeapWordSize = 2;
249 #endif
250 const int HeapWordsPerLong = BytesPerLong / HeapWordSize;
251 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize;
252
253 // The minimum number of native machine words necessary to contain "byte_size"
254 // bytes.
255 inline size_t heap_word_size(size_t byte_size) {
256 return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize;
257 }
258
259 inline jfloat jfloat_cast(jint x);
260 inline jdouble jdouble_cast(jlong x);
261
262 //-------------------------------------------
263 // Constant for jlong (standardized by C++11)
264
265 // Build a 64bit integer constant
266 #define CONST64(x) (x ## LL)
267 #define UCONST64(x) (x ## ULL)
268
269 const jlong min_jlong = CONST64(0x8000000000000000);
270 const jlong max_jlong = CONST64(0x7fffffffffffffff);
271
272 // for timer info max values which include all bits, 0xffffffffffffffff
273 const jlong all_bits_jlong = ~jlong(0);
274
275 //-------------------------------------------
276 // Constant for jdouble
277 const jlong min_jlongDouble = CONST64(0x0000000000000001);
278 const jdouble min_jdouble = jdouble_cast(min_jlongDouble);
279 const jlong max_jlongDouble = CONST64(0x7fefffffffffffff);
280 const jdouble max_jdouble = jdouble_cast(max_jlongDouble);
281
282 const size_t K = 1024;
283 const size_t M = K*K;
284 const size_t G = M*K;
285
286 // Constants for converting from a base unit to milli-base units. For
287 // example from seconds to milliseconds and microseconds
288
289 const int MILLIUNITS = 1000; // milli units per base unit
290 const int MICROUNITS = 1000000; // micro units per base unit
291 const int NANOUNITS = 1000000000; // nano units per base unit
292 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS;
293
294 const jlong NANOSECS_PER_SEC = CONST64(1000000000);
295 const jint NANOSECS_PER_MILLISEC = 1000000;
296
297
298 // Unit conversion functions
299 // The caller is responsible for considering overflow.
300
301 inline int64_t nanos_to_millis(int64_t nanos) {
302 return nanos / NANOUNITS_PER_MILLIUNIT;
303 }
304 inline int64_t millis_to_nanos(int64_t millis) {
305 return millis * NANOUNITS_PER_MILLIUNIT;
306 }
307
308 // Proper units routines try to maintain at least three significant digits.
309 // In worst case, it would print five significant digits with lower prefix.
310 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow,
311 // and therefore we need to be careful.
312
313 inline const char* proper_unit_for_byte_size(size_t s) {
314 #ifdef _LP64
315 if (s >= 100*G) {
316 return "G";
317 }
318 #endif
319 if (s >= 100*M) {
320 return "M";
321 } else if (s >= 100*K) {
322 return "K";
323 } else {
324 return "B";
325 }
326 }
327
328 template <class T>
329 inline T byte_size_in_proper_unit(T s) {
330 #ifdef _LP64
331 if (s >= 100*G) {
332 return (T)(s/G);
333 }
334 #endif
335 if (s >= 100*M) {
336 return (T)(s/M);
337 } else if (s >= 100*K) {
338 return (T)(s/K);
339 } else {
340 return s;
341 }
342 }
343
344 #define PROPERFMT "%zu%s"
345 #define PROPERFMTARGS(s) byte_size_in_proper_unit(s), proper_unit_for_byte_size(s)
346
347 // Printing a range, with start and bytes given
348 #define RANGEFMT "[" PTR_FORMAT " - " PTR_FORMAT "), (%zu bytes)"
349 #define RANGEFMTARGS(p1, size) p2i(p1), p2i(p1 + size), size
350
351 // Printing a range, with start and end given
352 #define RANGE2FMT "[" PTR_FORMAT " - " PTR_FORMAT "), (%zu bytes)"
353 #define RANGE2FMTARGS(p1, p2) p2i(p1), p2i(p2), ((uintptr_t)p2 - (uintptr_t)p1)
354
355 inline const char* exact_unit_for_byte_size(size_t s) {
356 #ifdef _LP64
357 if (s >= G && (s % G) == 0) {
358 return "G";
359 }
360 #endif
361 if (s >= M && (s % M) == 0) {
362 return "M";
363 }
364 if (s >= K && (s % K) == 0) {
365 return "K";
366 }
367 return "B";
368 }
369
370 inline size_t byte_size_in_exact_unit(size_t s) {
371 #ifdef _LP64
372 if (s >= G && (s % G) == 0) {
373 return s / G;
374 }
375 #endif
376 if (s >= M && (s % M) == 0) {
377 return s / M;
378 }
379 if (s >= K && (s % K) == 0) {
380 return s / K;
381 }
382 return s;
383 }
384
385 #define EXACTFMT "%zu%s"
386 #define EXACTFMTARGS(s) byte_size_in_exact_unit(s), exact_unit_for_byte_size(s)
387
388 // Memory size transition formatting.
389
390 #define HEAP_CHANGE_FORMAT "%s: %zuK(%zuK)->%zuK(%zuK)"
391
392 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \
393 (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K
394
395 //----------------------------------------------------------------------------------------------------
396 // VM type definitions
397
398 // intx and uintx are the 'extended' int and 'extended' unsigned int types;
399 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.
400
401 typedef intptr_t intx;
402 typedef uintptr_t uintx;
403
404 const intx min_intx = (intx)1 << (sizeof(intx)*BitsPerByte-1);
405 const intx max_intx = (uintx)min_intx - 1;
406 const uintx max_uintx = (uintx)-1;
407
408 // Table of values:
409 // sizeof intx 4 8
410 // min_intx 0x80000000 0x8000000000000000
411 // max_intx 0x7FFFFFFF 0x7FFFFFFFFFFFFFFF
412 // max_uintx 0xFFFFFFFF 0xFFFFFFFFFFFFFFFF
413
414 typedef unsigned int uint; NEEDS_CLEANUP
415
416 //----------------------------------------------------------------------------------------------------
417 // Java type definitions
418
419 // All kinds of 'plain' byte addresses
420 typedef signed char s_char;
421 typedef unsigned char u_char;
422 typedef u_char* address;
423 typedef const u_char* const_address;
424
425 // Pointer subtraction.
426 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have
427 // the range we might need to find differences from one end of the heap
428 // to the other.
429 // A typical use might be:
430 // if (pointer_delta(end(), top()) >= size) {
431 // // enough room for an object of size
432 // ...
433 // and then additions like
434 // ... top() + size ...
435 // are safe because we know that top() is at least size below end().
436 inline size_t pointer_delta(const volatile void* left,
437 const volatile void* right,
438 size_t element_size) {
439 assert(left >= right, "avoid underflow - left: " PTR_FORMAT " right: " PTR_FORMAT, p2i(left), p2i(right));
440 return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;
441 }
442
443 // A version specialized for HeapWord*'s.
444 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {
445 return pointer_delta(left, right, sizeof(HeapWord));
446 }
447 // A version specialized for MetaWord*'s.
448 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) {
449 return pointer_delta(left, right, sizeof(MetaWord));
450 }
451
452 // pointer_delta_as_int is called to do pointer subtraction for nearby pointers that
453 // returns a non-negative int, usually used as a size of a code buffer range.
454 // This scales to sizeof(T).
455 template <typename T>
456 inline int pointer_delta_as_int(const volatile T* left, const volatile T* right) {
457 size_t delta = pointer_delta(left, right, sizeof(T));
458 assert(delta <= size_t(INT_MAX), "pointer delta out of range: %zu", delta);
459 return static_cast<int>(delta);
460 }
461
462 //
463 // ANSI C++ does not allow casting from one pointer type to a function pointer
464 // directly without at best a warning. This macro accomplishes it silently
465 // In every case that is present at this point the value be cast is a pointer
466 // to a C linkage function. In some case the type used for the cast reflects
467 // that linkage and a picky compiler would not complain. In other cases because
468 // there is no convenient place to place a typedef with extern C linkage (i.e
469 // a platform dependent header file) it doesn't. At this point no compiler seems
470 // picky enough to catch these instances (which are few). It is possible that
471 // using templates could fix these for all cases. This use of templates is likely
472 // so far from the middle of the road that it is likely to be problematic in
473 // many C++ compilers.
474 //
475 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value))
476 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((uintptr_t)(func_ptr)))
477
478 // Need the correct linkage to call qsort without warnings
479 extern "C" {
480 typedef int (*_sort_Fn)(const void *, const void *);
481 }
482
483 // Additional Java basic types
484
485 typedef uint8_t jubyte;
486 typedef uint16_t jushort;
487 typedef uint32_t juint;
488 typedef uint64_t julong;
489
490 // Unsigned byte types for os and stream.hpp
491
492 // Unsigned one, two, four and eight byte quantities used for describing
493 // the .class file format. See JVM book chapter 4.
494
495 typedef jubyte u1;
496 typedef jushort u2;
497 typedef juint u4;
498 typedef julong u8;
499
500 const jubyte max_jubyte = (jubyte)-1; // 0xFF largest jubyte
501 const jushort max_jushort = (jushort)-1; // 0xFFFF largest jushort
502 const juint max_juint = (juint)-1; // 0xFFFFFFFF largest juint
503 const julong max_julong = (julong)-1; // 0xFF....FF largest julong
504
505 typedef jbyte s1;
506 typedef jshort s2;
507 typedef jint s4;
508 typedef jlong s8;
509
510 const jbyte min_jbyte = -(1 << 7); // smallest jbyte
511 const jbyte max_jbyte = (1 << 7) - 1; // largest jbyte
512 const jshort min_jshort = -(1 << 15); // smallest jshort
513 const jshort max_jshort = (1 << 15) - 1; // largest jshort
514
515 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
516 const jint max_jint = (juint)min_jint - 1; // 0x7FFFFFFF == largest jint
517
518 const jint min_jintFloat = (jint)(0x00000001);
519 const jfloat min_jfloat = jfloat_cast(min_jintFloat);
520 const jint max_jintFloat = (jint)(0x7f7fffff);
521 const jfloat max_jfloat = jfloat_cast(max_jintFloat);
522
523 const jshort max_jfloat16 = 31743;
524 const jshort min_jfloat16 = 1;
525 const jshort one_jfloat16 = 15360;
526 const jshort pos_inf_jfloat16 = 31744;
527 const jshort neg_inf_jfloat16 = -1024;
528 // A named constant for the integral representation of a Java null.
529 const intptr_t NULL_WORD = 0;
530
531 //----------------------------------------------------------------------------------------------------
532 // JVM spec restrictions
533
534 const int max_method_code_size = 64*K - 1; // JVM spec, 2nd ed. section 4.8.1 (p.134)
535
536 //----------------------------------------------------------------------------------------------------
537 // old CDS options
538 extern bool RequireSharedSpaces;
539 extern "C" {
540 // Make sure UseSharedSpaces is accessible to the serviceability agent.
541 extern JNIEXPORT jboolean UseSharedSpaces;
542 }
543
544 //----------------------------------------------------------------------------------------------------
545 // Object alignment, in units of HeapWords.
546 //
547 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and
548 // reference fields can be naturally aligned.
549
550 extern int MinObjAlignment;
551 extern int MinObjAlignmentInBytes;
552 extern int MinObjAlignmentInBytesMask;
553
554 extern int LogMinObjAlignment;
555 extern int LogMinObjAlignmentInBytes;
556
557 // Maximal size of heap where unscaled compression can be used. Also upper bound
558 // for heap placement: 4GB.
559 const uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
560 // Maximal size of heap where compressed oops can be used. Also upper bound for heap
561 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes.
562 extern uint64_t OopEncodingHeapMax;
563
564 // Machine dependent stuff
565
566 #include CPU_HEADER(globalDefinitions)
567
568 // The maximum size of the code cache. Can be overridden by targets.
569 #ifndef CODE_CACHE_SIZE_LIMIT
570 #define CODE_CACHE_SIZE_LIMIT (2*G)
571 #endif
572
573 // Allow targets to reduce the default size of the code cache.
574 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT
575
576 // To assure the IRIW property on processors that are not multiple copy
577 // atomic, sync instructions must be issued between volatile reads to
578 // assure their ordering, instead of after volatile stores.
579 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models"
580 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge)
581 #ifdef CPU_MULTI_COPY_ATOMIC
582 // Not needed.
583 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false;
584 #else
585 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment.
586 // Final decision is subject to JEP 188: Java Memory Model Update.
587 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false);
588 #endif
589
590 // The expected size in bytes of a cache line.
591 #ifndef DEFAULT_CACHE_LINE_SIZE
592 #error "Platform should define DEFAULT_CACHE_LINE_SIZE"
593 #endif
594
595 // The default padding size for data structures to avoid false sharing.
596 #ifndef DEFAULT_PADDING_SIZE
597 #error "Platform should define DEFAULT_PADDING_SIZE"
598 #endif
599
600
601 //----------------------------------------------------------------------------------------------------
602 // Prototyping
603 // "Code Missing Here" macro, un-define when integrating back from prototyping stage and break
604 // compilation on purpose (i.e. "forget me not")
605 #define PROTOTYPE
606 #ifdef PROTOTYPE
607 #define CMH(m)
608 #endif
609
610 //----------------------------------------------------------------------------------------------------
611 // Miscellaneous
612
613 // 6302670 Eliminate Hotspot __fabsf dependency
614 // All fabs() callers should call this function instead, which will implicitly
615 // convert the operand to double, avoiding a dependency on __fabsf which
616 // doesn't exist in early versions of Solaris 8.
617 inline double fabsd(double value) {
618 return fabs(value);
619 }
620
621 // Returns numerator/denominator as percentage value from 0 to 100. If denominator
622 // is zero, return 0.0.
623 template<typename T>
624 inline double percent_of(T numerator, T denominator) {
625 return denominator != 0 ? (double)numerator / (double)denominator * 100.0 : 0.0;
626 }
627
628 //----------------------------------------------------------------------------------------------------
629 // Special casts
630 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern
631 typedef union {
632 jfloat f;
633 jint i;
634 } FloatIntConv;
635
636 typedef union {
637 jdouble d;
638 jlong l;
639 julong ul;
640 } DoubleLongConv;
641
642 inline jint jint_cast (jfloat x) { return ((FloatIntConv*)&x)->i; }
643 inline jfloat jfloat_cast (jint x) { return ((FloatIntConv*)&x)->f; }
644
645 inline jlong jlong_cast (jdouble x) { return ((DoubleLongConv*)&x)->l; }
646 inline julong julong_cast (jdouble x) { return ((DoubleLongConv*)&x)->ul; }
647 inline jdouble jdouble_cast (jlong x) { return ((DoubleLongConv*)&x)->d; }
648
649 inline jint low (jlong value) { return jint(value); }
650 inline jint high(jlong value) { return jint(value >> 32); }
651
652 // the fancy casts are a hopefully portable way
653 // to do unsigned 32 to 64 bit type conversion
654 inline void set_low (jlong* value, jint low ) { *value &= (jlong)0xffffffff << 32;
655 *value |= (jlong)(julong)(juint)low; }
656
657 inline void set_high(jlong* value, jint high) { *value &= (jlong)(julong)(juint)0xffffffff;
658 *value |= (jlong)high << 32; }
659
660 inline jlong jlong_from(jint h, jint l) {
661 jlong result = 0; // initialization to avoid warning
662 set_high(&result, h);
663 set_low(&result, l);
664 return result;
665 }
666
667 union jlong_accessor {
668 jint words[2];
669 jlong long_value;
670 };
671
672 void basic_types_init(); // cannot define here; uses assert
673
674
675 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
676 enum BasicType : u1 {
677 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS.
678 T_BOOLEAN = JVM_T_BOOLEAN,
679 T_CHAR = JVM_T_CHAR,
680 T_FLOAT = JVM_T_FLOAT,
681 T_DOUBLE = JVM_T_DOUBLE,
682 T_BYTE = JVM_T_BYTE,
683 T_SHORT = JVM_T_SHORT,
684 T_INT = JVM_T_INT,
685 T_LONG = JVM_T_LONG,
686 // The remaining values are not part of any standard.
687 // T_OBJECT and T_VOID denote two more semantic choices
688 // for method return values.
689 // T_OBJECT and T_ARRAY describe signature syntax.
690 // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe
691 // internal references within the JVM as if they were Java
692 // types in their own right.
693 T_OBJECT = 12,
694 T_ARRAY = 13,
695 T_FLAT_ELEMENT = 14, // Not a true BasicType, only use in headers of flat arrays
696 T_VOID = 15,
697 T_ADDRESS = 16,
698 T_NARROWOOP = 17,
699 T_METADATA = 18,
700 T_NARROWKLASS = 19,
701 T_CONFLICT = 20, // for stack value type with conflicting contents
702 T_ILLEGAL = 99
703 };
704
705 #define SIGNATURE_TYPES_DO(F, N) \
706 F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N) \
707 F(JVM_SIGNATURE_CHAR, T_CHAR, N) \
708 F(JVM_SIGNATURE_FLOAT, T_FLOAT, N) \
709 F(JVM_SIGNATURE_DOUBLE, T_DOUBLE, N) \
710 F(JVM_SIGNATURE_BYTE, T_BYTE, N) \
711 F(JVM_SIGNATURE_SHORT, T_SHORT, N) \
712 F(JVM_SIGNATURE_INT, T_INT, N) \
713 F(JVM_SIGNATURE_LONG, T_LONG, N) \
714 F(JVM_SIGNATURE_CLASS, T_OBJECT, N) \
715 F(JVM_SIGNATURE_ARRAY, T_ARRAY, N) \
716 F(JVM_SIGNATURE_FLAT_ELEMENT, T_FLAT_ELEMENT, N) \
717 F(JVM_SIGNATURE_VOID, T_VOID, N) \
718 /*end*/
719
720 inline bool is_java_type(BasicType t) {
721 return T_BOOLEAN <= t && t <= T_VOID;
722 }
723
724 inline bool is_java_primitive(BasicType t) {
725 return T_BOOLEAN <= t && t <= T_LONG;
726 }
727
728 inline bool is_subword_type(BasicType t) {
729 // these guys are processed exactly like T_INT in calling sequences:
730 return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);
731 }
732
733 inline bool is_signed_subword_type(BasicType t) {
734 return (t == T_BYTE || t == T_SHORT);
735 }
736
737 inline bool is_unsigned_subword_type(BasicType t) {
738 return (t == T_BOOLEAN || t == T_CHAR);
739 }
740
741 inline bool is_double_word_type(BasicType t) {
742 return (t == T_DOUBLE || t == T_LONG);
743 }
744
745 inline bool is_reference_type(BasicType t, bool include_narrow_oop = false) {
746 return (t == T_OBJECT || t == T_ARRAY || t == T_FLAT_ELEMENT || (include_narrow_oop && t == T_NARROWOOP));
747 }
748
749 inline bool is_integral_type(BasicType t) {
750 return is_subword_type(t) || t == T_INT || t == T_LONG;
751 }
752
753 inline bool is_non_subword_integral_type(BasicType t) {
754 return t == T_INT || t == T_LONG;
755 }
756
757 inline bool is_floating_point_type(BasicType t) {
758 return (t == T_FLOAT || t == T_DOUBLE);
759 }
760
761 extern char type2char_tab[T_CONFLICT+1]; // Map a BasicType to a jchar
762 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }
763 extern int type2size[T_CONFLICT+1]; // Map BasicType to result stack elements
764 extern const char* type2name_tab[T_CONFLICT+1]; // Map a BasicType to a char*
765 extern BasicType name2type(const char* name);
766
767 const char* type2name(BasicType t);
768
769 inline jlong max_signed_integer(BasicType bt) {
770 if (bt == T_INT) {
771 return max_jint;
772 }
773 assert(bt == T_LONG, "unsupported");
774 return max_jlong;
775 }
776
777 inline jlong min_signed_integer(BasicType bt) {
778 if (bt == T_INT) {
779 return min_jint;
780 }
781 assert(bt == T_LONG, "unsupported");
782 return min_jlong;
783 }
784
785 inline uint bits_per_java_integer(BasicType bt) {
786 if (bt == T_INT) {
787 return BitsPerJavaInteger;
788 }
789 assert(bt == T_LONG, "int or long only");
790 return BitsPerJavaLong;
791 }
792
793 // Auxiliary math routines
794 // least common multiple
795 extern size_t lcm(size_t a, size_t b);
796
797
798 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
799 enum BasicTypeSize {
800 T_BOOLEAN_size = 1,
801 T_CHAR_size = 1,
802 T_FLOAT_size = 1,
803 T_DOUBLE_size = 2,
804 T_BYTE_size = 1,
805 T_SHORT_size = 1,
806 T_INT_size = 1,
807 T_LONG_size = 2,
808 T_OBJECT_size = 1,
809 T_ARRAY_size = 1,
810 T_NARROWOOP_size = 1,
811 T_NARROWKLASS_size = 1,
812 T_VOID_size = 0,
813 T_FLAT_ELEMENT_size = 1
814 };
815
816 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc.
817 inline int parameter_type_word_count(BasicType t) {
818 if (is_double_word_type(t)) return 2;
819 assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please");
820 assert(type2size[t] == 1, "must be");
821 return 1;
822 }
823
824 // maps a BasicType to its instance field storage type:
825 // all sub-word integral types are widened to T_INT
826 extern BasicType type2field[T_CONFLICT+1];
827 extern BasicType type2wfield[T_CONFLICT+1];
828
829
830 // size in bytes
831 enum ArrayElementSize {
832 T_BOOLEAN_aelem_bytes = 1,
833 T_CHAR_aelem_bytes = 2,
834 T_FLOAT_aelem_bytes = 4,
835 T_DOUBLE_aelem_bytes = 8,
836 T_BYTE_aelem_bytes = 1,
837 T_SHORT_aelem_bytes = 2,
838 T_INT_aelem_bytes = 4,
839 T_LONG_aelem_bytes = 8,
840 #ifdef _LP64
841 T_OBJECT_aelem_bytes = 8,
842 T_ARRAY_aelem_bytes = 8,
843 T_FLAT_ELEMENT_aelem_bytes = 8,
844 #else
845 T_OBJECT_aelem_bytes = 4,
846 T_ARRAY_aelem_bytes = 4,
847 T_FLAT_ELEMENT_aelem_bytes = 4,
848 #endif
849 T_NARROWOOP_aelem_bytes = 4,
850 T_NARROWKLASS_aelem_bytes = 4,
851 T_VOID_aelem_bytes = 0
852 };
853
854 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element
855 #ifdef ASSERT
856 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts
857 #else
858 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; }
859 #endif
860
861 inline bool same_type_or_subword_size(BasicType t1, BasicType t2) {
862 return (t1 == t2) || (is_subword_type(t1) && type2aelembytes(t1) == type2aelembytes(t2));
863 }
864
865 // JavaValue serves as a container for arbitrary Java values.
866
867 class JavaValue {
868
869 public:
870 typedef union JavaCallValue {
871 jfloat f;
872 jdouble d;
873 jint i;
874 jlong l;
875 jobject h;
876 oopDesc* o;
877 } JavaCallValue;
878
879 private:
880 BasicType _type;
881 JavaCallValue _value;
882
883 public:
884 JavaValue(BasicType t = T_ILLEGAL) { _type = t; }
885
886 JavaValue(jfloat value) {
887 _type = T_FLOAT;
888 _value.f = value;
889 }
890
891 JavaValue(jdouble value) {
892 _type = T_DOUBLE;
893 _value.d = value;
894 }
895
896 jfloat get_jfloat() const { return _value.f; }
897 jdouble get_jdouble() const { return _value.d; }
898 jint get_jint() const { return _value.i; }
899 jlong get_jlong() const { return _value.l; }
900 jobject get_jobject() const { return _value.h; }
901 oopDesc* get_oop() const { return _value.o; }
902 JavaCallValue* get_value_addr() { return &_value; }
903 BasicType get_type() const { return _type; }
904
905 void set_jfloat(jfloat f) { _value.f = f;}
906 void set_jdouble(jdouble d) { _value.d = d;}
907 void set_jint(jint i) { _value.i = i;}
908 void set_jshort(jshort i) { _value.i = i;}
909 void set_jlong(jlong l) { _value.l = l;}
910 void set_jobject(jobject h) { _value.h = h;}
911 void set_oop(oopDesc* o) { _value.o = o;}
912 void set_type(BasicType t) { _type = t; }
913
914 jboolean get_jboolean() const { return (jboolean) (_value.i);}
915 jbyte get_jbyte() const { return (jbyte) (_value.i);}
916 jchar get_jchar() const { return (jchar) (_value.i);}
917 jshort get_jshort() const { return (jshort) (_value.i);}
918
919 };
920
921
922 // TosState describes the top-of-stack state before and after the execution of
923 // a bytecode or method. The top-of-stack value may be cached in one or more CPU
924 // registers. The TosState corresponds to the 'machine representation' of this cached
925 // value. There's 4 states corresponding to the JAVA types int, long, float & double
926 // as well as a 5th state in case the top-of-stack value is actually on the top
927 // of stack (in memory) and thus not cached. The atos state corresponds to the itos
928 // state when it comes to machine representation but is used separately for (oop)
929 // type specific operations (e.g. verification code).
930
931 enum TosState { // describes the tos cache contents
932 btos = 0, // byte, bool tos cached
933 ztos = 1, // byte, bool tos cached
934 ctos = 2, // char tos cached
935 stos = 3, // short tos cached
936 itos = 4, // int tos cached
937 ltos = 5, // long tos cached
938 ftos = 6, // float tos cached
939 dtos = 7, // double tos cached
940 atos = 8, // object cached
941 vtos = 9, // tos not cached,
942 number_of_states,
943 ilgl // illegal state: should not occur
944 };
945
946
947 inline TosState as_TosState(BasicType type) {
948 switch (type) {
949 case T_BYTE : return btos;
950 case T_BOOLEAN: return ztos;
951 case T_CHAR : return ctos;
952 case T_SHORT : return stos;
953 case T_INT : return itos;
954 case T_LONG : return ltos;
955 case T_FLOAT : return ftos;
956 case T_DOUBLE : return dtos;
957 case T_VOID : return vtos;
958 case T_ARRAY : // fall through
959 case T_OBJECT : return atos;
960 default : return ilgl;
961 }
962 }
963
964 inline BasicType as_BasicType(TosState state) {
965 switch (state) {
966 case btos : return T_BYTE;
967 case ztos : return T_BOOLEAN;
968 case ctos : return T_CHAR;
969 case stos : return T_SHORT;
970 case itos : return T_INT;
971 case ltos : return T_LONG;
972 case ftos : return T_FLOAT;
973 case dtos : return T_DOUBLE;
974 case atos : return T_OBJECT;
975 case vtos : return T_VOID;
976 default : return T_ILLEGAL;
977 }
978 }
979
980
981 // Helper function to convert BasicType info into TosState
982 // Note: Cannot define here as it uses global constant at the time being.
983 TosState as_TosState(BasicType type);
984
985
986 // JavaThreadState keeps track of which part of the code a thread is executing in. This
987 // information is needed by the safepoint code.
988 //
989 // There are 4 essential states:
990 //
991 // _thread_new : Just started, but not executed init. code yet (most likely still in OS init code)
992 // _thread_in_native : In native code. This is a safepoint region, since all oops will be in jobject handles
993 // _thread_in_vm : Executing in the vm
994 // _thread_in_Java : Executing either interpreted or compiled Java code (or could be in a stub)
995 //
996 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in
997 // a transition from one state to another. These extra states makes it possible for the safepoint code to
998 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.
999 //
1000 // Given a state, the xxxx_trans state can always be found by adding 1.
1001 //
1002 enum JavaThreadState {
1003 _thread_uninitialized = 0, // should never happen (missing initialization)
1004 _thread_new = 2, // just starting up, i.e., in process of being initialized
1005 _thread_new_trans = 3, // corresponding transition state (not used, included for completeness)
1006 _thread_in_native = 4, // running in native code
1007 _thread_in_native_trans = 5, // corresponding transition state
1008 _thread_in_vm = 6, // running in VM
1009 _thread_in_vm_trans = 7, // corresponding transition state
1010 _thread_in_Java = 8, // running in Java or in stub code
1011 _thread_in_Java_trans = 9, // corresponding transition state (not used, included for completeness)
1012 _thread_blocked = 10, // blocked in vm
1013 _thread_blocked_trans = 11, // corresponding transition state
1014 _thread_max_state = 12 // maximum thread state+1 - used for statistics allocation
1015 };
1016
1017 enum LockingMode {
1018 // Use only heavy monitors for locking
1019 LM_MONITOR = 0,
1020 // Legacy stack-locking, with monitors as 2nd tier
1021 LM_LEGACY = 1,
1022 // New lightweight locking, with monitors as 2nd tier
1023 LM_LIGHTWEIGHT = 2
1024 };
1025
1026 //----------------------------------------------------------------------------------------------------
1027 // Special constants for debugging
1028
1029 const jint badInt = -3; // generic "bad int" value
1030 const intptr_t badAddressVal = -2; // generic "bad address" value
1031 const intptr_t badOopVal = -1; // generic "bad oop" value
1032 const intptr_t badHeapOopVal = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC
1033 const int badStackSegVal = 0xCA; // value used to zap stack segments
1034 const int badHandleValue = 0xBC; // value used to zap vm handle area
1035 const int badResourceValue = 0xAB; // value used to zap resource area
1036 const int freeBlockPad = 0xBA; // value used to pad freed blocks.
1037 const int uninitBlockPad = 0xF1; // value used to zap newly malloc'd blocks.
1038 const juint uninitMetaWordVal = 0xf7f7f7f7; // value used to zap newly allocated metachunk
1039 const jubyte heapPaddingByteVal = 0xBD; // value used to zap object padding in the heap
1040 const juint badHeapWordVal = 0xBAADBABE; // value used to zap heap after GC
1041 const int badCodeHeapNewVal = 0xCC; // value used to zap Code heap at allocation
1042 const int badCodeHeapFreeVal = 0xDD; // value used to zap Code heap at deallocation
1043 const intptr_t badDispHeaderDeopt = 0xDE0BD000; // value to fill unused displaced header during deoptimization
1044 const intptr_t badDispHeaderOSR = 0xDEAD05A0; // value to fill unused displaced header during OSR
1045
1046 // (These must be implemented as #defines because C++ compilers are
1047 // not obligated to inline non-integral constants!)
1048 #define badAddress ((address)::badAddressVal)
1049 #define badHeapWord (::badHeapWordVal)
1050
1051 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)
1052 const uint TASKQUEUE_SIZE = (NOT_LP64(1<<14) LP64_ONLY(1<<17));
1053
1054 //----------------------------------------------------------------------------------------------------
1055 // Utility functions for bitfield manipulations
1056
1057 const intptr_t AllBits = ~0; // all bits set in a word
1058 const intptr_t NoBits = 0; // no bits set in a word
1059 const jlong NoLongBits = 0; // no bits set in a long
1060 const intptr_t OneBit = 1; // only right_most bit set in a word
1061
1062 // get a word with the n.th or the right-most or left-most n bits set
1063 // (note: #define used only so that they can be used in enum constant definitions)
1064 #define nth_bit(n) (((n) >= BitsPerWord) ? 0 : (OneBit << (n)))
1065 #define right_n_bits(n) (nth_bit(n) - 1)
1066
1067 // bit-operations using a mask m
1068 inline void set_bits (intptr_t& x, intptr_t m) { x |= m; }
1069 inline void clear_bits (intptr_t& x, intptr_t m) { x &= ~m; }
1070 inline intptr_t mask_bits (intptr_t x, intptr_t m) { return x & m; }
1071 inline jlong mask_long_bits (jlong x, jlong m) { return x & m; }
1072 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }
1073
1074 // bit-operations using the n.th bit
1075 inline void set_nth_bit(intptr_t& x, int n) { set_bits (x, nth_bit(n)); }
1076 inline void clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }
1077 inline bool is_set_nth_bit(intptr_t x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }
1078
1079 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)
1080 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {
1081 return mask_bits(x >> start_bit_no, right_n_bits(field_length));
1082 }
1083
1084
1085 //----------------------------------------------------------------------------------------------------
1086 // Utility functions for integers
1087
1088 // Avoid use of global min/max macros which may cause unwanted double
1089 // evaluation of arguments.
1090 #ifdef max
1091 #undef max
1092 #endif
1093
1094 #ifdef min
1095 #undef min
1096 #endif
1097
1098 // It is necessary to use templates here. Having normal overloaded
1099 // functions does not work because it is necessary to provide both 32-
1100 // and 64-bit overloaded functions, which does not work, and having
1101 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)
1102 // will be even more error-prone than macros.
1103 template<class T> constexpr T MAX2(T a, T b) { return (a > b) ? a : b; }
1104 template<class T> constexpr T MIN2(T a, T b) { return (a < b) ? a : b; }
1105 template<class T> constexpr T MAX3(T a, T b, T c) { return MAX2(MAX2(a, b), c); }
1106 template<class T> constexpr T MIN3(T a, T b, T c) { return MIN2(MIN2(a, b), c); }
1107 template<class T> constexpr T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }
1108 template<class T> constexpr T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }
1109
1110 #define ABS(x) asserted_abs(x, __FILE__, __LINE__)
1111
1112 template<class T> inline T asserted_abs(T x, const char* file, int line) {
1113 bool valid_arg = !(std::is_integral<T>::value && x == std::numeric_limits<T>::min());
1114 #ifdef ASSERT
1115 if (!valid_arg) {
1116 report_vm_error(file, line, "ABS: argument should not allow overflow");
1117 }
1118 #endif
1119 // Prevent exposure to UB by checking valid_arg here as well.
1120 return (x < 0 && valid_arg) ? -x : x;
1121 }
1122
1123 // Return the given value clamped to the range [min ... max]
1124 template<typename T>
1125 inline T clamp(T value, T min, T max) {
1126 assert(min <= max, "must be");
1127 return MIN2(MAX2(value, min), max);
1128 }
1129
1130 inline bool is_odd (intx x) { return x & 1; }
1131 inline bool is_even(intx x) { return !is_odd(x); }
1132
1133 // abs methods which cannot overflow and so are well-defined across
1134 // the entire domain of integer types.
1135 static inline unsigned int uabs(unsigned int n) {
1136 union {
1137 unsigned int result;
1138 int value;
1139 };
1140 result = n;
1141 if (value < 0) result = 0-result;
1142 return result;
1143 }
1144 static inline julong uabs(julong n) {
1145 union {
1146 julong result;
1147 jlong value;
1148 };
1149 result = n;
1150 if (value < 0) result = 0-result;
1151 return result;
1152 }
1153 static inline julong uabs(jlong n) { return uabs((julong)n); }
1154 static inline unsigned int uabs(int n) { return uabs((unsigned int)n); }
1155
1156 // "to" should be greater than "from."
1157 inline size_t byte_size(void* from, void* to) {
1158 return pointer_delta(to, from, sizeof(char));
1159 }
1160
1161 // Pack and extract shorts to/from ints:
1162
1163 inline u2 extract_low_short_from_int(u4 x) {
1164 return u2(x & 0xffff);
1165 }
1166
1167 inline u2 extract_high_short_from_int(u4 x) {
1168 return u2((x >> 16) & 0xffff);
1169 }
1170
1171 inline int build_int_from_shorts( u2 low, u2 high ) {
1172 return ((int)((unsigned int)high << 16) | (unsigned int)low);
1173 }
1174
1175 // swap a & b
1176 template<class T> static void swap(T& a, T& b) {
1177 T tmp = a;
1178 a = b;
1179 b = tmp;
1180 }
1181
1182 // array_size_impl is a function that takes a reference to T[N] and
1183 // returns a reference to char[N]. It is not ODR-used, so not defined.
1184 template<typename T, size_t N> char (&array_size_impl(T (&)[N]))[N];
1185
1186 #define ARRAY_SIZE(array) sizeof(array_size_impl(array))
1187
1188 //----------------------------------------------------------------------------------------------------
1189 // Sum and product which can never overflow: they wrap, just like the
1190 // Java operations. Note that we don't intend these to be used for
1191 // general-purpose arithmetic: their purpose is to emulate Java
1192 // operations.
1193
1194 // The goal of this code to avoid undefined or implementation-defined
1195 // behavior. The use of an lvalue to reference cast is explicitly
1196 // permitted by Lvalues and rvalues [basic.lval]. [Section 3.10 Para
1197 // 15 in C++03]
1198 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE) \
1199 inline TYPE NAME (TYPE in1, TYPE in2) { \
1200 UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \
1201 ures OP ## = static_cast<UNSIGNED_TYPE>(in2); \
1202 return reinterpret_cast<TYPE&>(ures); \
1203 }
1204
1205 JAVA_INTEGER_OP(+, java_add, jint, juint)
1206 JAVA_INTEGER_OP(-, java_subtract, jint, juint)
1207 JAVA_INTEGER_OP(*, java_multiply, jint, juint)
1208 JAVA_INTEGER_OP(+, java_add, jlong, julong)
1209 JAVA_INTEGER_OP(-, java_subtract, jlong, julong)
1210 JAVA_INTEGER_OP(*, java_multiply, jlong, julong)
1211
1212 inline jint java_negate(jint v) { return java_subtract((jint) 0, v); }
1213 inline jlong java_negate(jlong v) { return java_subtract((jlong)0, v); }
1214
1215 #undef JAVA_INTEGER_OP
1216
1217 // Provide integer shift operations with Java semantics. No overflow
1218 // issues - left shifts simply discard shifted out bits. No undefined
1219 // behavior for large or negative shift quantities; instead the actual
1220 // shift distance is the argument modulo the lhs value's size in bits.
1221 // No undefined or implementation defined behavior for shifting negative
1222 // values; left shift discards bits, right shift sign extends. We use
1223 // the same safe conversion technique as above for java_add and friends.
1224 #define JAVA_INTEGER_SHIFT_OP(OP, NAME, TYPE, XTYPE) \
1225 inline TYPE NAME (TYPE lhs, jint rhs) { \
1226 const uint rhs_mask = (sizeof(TYPE) * 8) - 1; \
1227 STATIC_ASSERT(rhs_mask == 31 || rhs_mask == 63); \
1228 XTYPE xres = static_cast<XTYPE>(lhs); \
1229 xres OP ## = (rhs & rhs_mask); \
1230 return reinterpret_cast<TYPE&>(xres); \
1231 }
1232
1233 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jint, juint)
1234 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jlong, julong)
1235
1236 // For signed shift right, assume C++ implementation >> sign extends.
1237 //
1238 // C++14 5.8/3: In the description of "E1 >> E2" it says "If E1 has a signed type
1239 // and a negative value, the resulting value is implementation-defined."
1240 //
1241 // However, C++20 7.6.7/3 further defines integral arithmetic, as part of
1242 // requiring two's-complement behavior.
1243 // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0907r3.html
1244 // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1236r1.html
1245 // The corresponding C++20 text is "Right-shift on signed integral types is an
1246 // arithmetic right shift, which performs sign-extension."
1247 //
1248 // As discussed in the two's complement proposal, all known modern C++ compilers
1249 // already behave that way. And it is unlikely any would go off and do something
1250 // different now, with C++20 tightening things up.
1251 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jint, jint)
1252 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jlong, jlong)
1253 // For >>> use C++ unsigned >>.
1254 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jint, juint)
1255 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jlong, julong)
1256
1257 #undef JAVA_INTEGER_SHIFT_OP
1258
1259 //----------------------------------------------------------------------------------------------------
1260 // The goal of this code is to provide saturating operations for int/uint.
1261 // Checks overflow conditions and saturates the result to min_jint/max_jint.
1262 #define SATURATED_INTEGER_OP(OP, NAME, TYPE1, TYPE2) \
1263 inline int NAME (TYPE1 in1, TYPE2 in2) { \
1264 jlong res = static_cast<jlong>(in1); \
1265 res OP ## = static_cast<jlong>(in2); \
1266 if (res > max_jint) { \
1267 res = max_jint; \
1268 } else if (res < min_jint) { \
1269 res = min_jint; \
1270 } \
1271 return static_cast<int>(res); \
1272 }
1273
1274 SATURATED_INTEGER_OP(+, saturated_add, int, int)
1275 SATURATED_INTEGER_OP(+, saturated_add, int, uint)
1276 SATURATED_INTEGER_OP(+, saturated_add, uint, int)
1277 SATURATED_INTEGER_OP(+, saturated_add, uint, uint)
1278
1279 #undef SATURATED_INTEGER_OP
1280
1281 // Taken from rom section 8-2 of Henry S. Warren, Jr., Hacker's Delight (2nd ed.) (Addison Wesley, 2013), 173-174.
1282 inline uint64_t multiply_high_unsigned(const uint64_t x, const uint64_t y) {
1283 const uint64_t x1 = x >> 32u;
1284 const uint64_t x2 = x & 0xFFFFFFFF;
1285 const uint64_t y1 = y >> 32u;
1286 const uint64_t y2 = y & 0xFFFFFFFF;
1287 const uint64_t z2 = x2 * y2;
1288 const uint64_t t = x1 * y2 + (z2 >> 32u);
1289 uint64_t z1 = t & 0xFFFFFFFF;
1290 const uint64_t z0 = t >> 32u;
1291 z1 += x2 * y1;
1292
1293 return x1 * y1 + z0 + (z1 >> 32u);
1294 }
1295
1296 // Taken from java.lang.Math::multiplyHigh which uses the technique from section 8-2 of Henry S. Warren, Jr.,
1297 // Hacker's Delight (2nd ed.) (Addison Wesley, 2013), 173-174 but adapted for signed longs.
1298 inline int64_t multiply_high_signed(const int64_t x, const int64_t y) {
1299 const jlong x1 = java_shift_right((jlong)x, 32);
1300 const jlong x2 = x & 0xFFFFFFFF;
1301 const jlong y1 = java_shift_right((jlong)y, 32);
1302 const jlong y2 = y & 0xFFFFFFFF;
1303
1304 const uint64_t z2 = (uint64_t)x2 * y2;
1305 const int64_t t = x1 * y2 + (z2 >> 32u); // Unsigned shift
1306 int64_t z1 = t & 0xFFFFFFFF;
1307 const int64_t z0 = java_shift_right((jlong)t, 32);
1308 z1 += x2 * y1;
1309
1310 return x1 * y1 + z0 + java_shift_right((jlong)z1, 32);
1311 }
1312
1313 // Dereference vptr
1314 // All C++ compilers that we know of have the vtbl pointer in the first
1315 // word. If there are exceptions, this function needs to be made compiler
1316 // specific.
1317 static inline void* dereference_vptr(const void* addr) {
1318 return *(void**)addr;
1319 }
1320
1321 //----------------------------------------------------------------------------------------------------
1322 // String type aliases used by command line flag declarations and
1323 // processing utilities.
1324
1325 typedef const char* ccstr;
1326 typedef const char* ccstrlist; // represents string arguments which accumulate
1327
1328 //----------------------------------------------------------------------------------------------------
1329 // Default hash/equals functions used by ResourceHashtable
1330
1331 template<typename K> unsigned primitive_hash(const K& k) {
1332 unsigned hash = (unsigned)((uintptr_t)k);
1333 return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs
1334 }
1335
1336 template<typename K> bool primitive_equals(const K& k0, const K& k1) {
1337 return k0 == k1;
1338 }
1339
1340 template<typename K> int primitive_compare(const K& k0, const K& k1) {
1341 return ((k0 < k1) ? -1 : (k0 == k1) ? 0 : 1);
1342 }
1343
1344 //----------------------------------------------------------------------------------------------------
1345
1346 // Allow use of C++ thread_local when approved - see JDK-8282469.
1347 #define APPROVED_CPP_THREAD_LOCAL thread_local
1348
1349 // Converts any type T to a reference type.
1350 template<typename T>
1351 std::add_rvalue_reference_t<T> declval() noexcept;
1352
1353 // Quickly test to make sure IEEE-754 subnormal numbers are correctly
1354 // handled.
1355 bool IEEE_subnormal_handling_OK();
1356
1357 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP