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