1 /*
2 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_UTILITIES_GLOBALDEFINITIONS_HPP
26 #define SHARE_UTILITIES_GLOBALDEFINITIONS_HPP
27
28 #include "utilities/attributeNoreturn.hpp"
29 #include "utilities/compilerWarnings.hpp"
30 #include "utilities/debug.hpp"
31 #include "utilities/macros.hpp"
32
33 // Get constants like JVM_T_CHAR and JVM_SIGNATURE_INT, before pulling in <jvm.h>.
34 #include "classfile_constants.h"
35
36 #include COMPILER_HEADER(utilities/globalDefinitions)
37
38 #include <cstddef>
39 #include <cstdint>
40 #include <type_traits>
41
42 class oopDesc;
43
44 // Defaults for macros that might be defined per compiler.
45 #ifndef NOINLINE
46 #define NOINLINE
47 #endif
48 #ifndef ALWAYSINLINE
49 #define ALWAYSINLINE inline
50 #endif
51
52 #ifndef ATTRIBUTE_ALIGNED
53 #define ATTRIBUTE_ALIGNED(x) alignas(x)
54 #endif
55
56 #ifndef ATTRIBUTE_FLATTEN
57 #define ATTRIBUTE_FLATTEN
58 #endif
59
60 // These are #defines to selectively turn on/off the Print(Opto)Assembly
61 // capabilities. Choices should be led by a tradeoff between
62 // code size and improved supportability.
63 // if PRINT_ASSEMBLY then PRINT_ABSTRACT_ASSEMBLY must be true as well
64 // to have a fallback in case hsdis is not available.
65 #if defined(PRODUCT)
66 #define SUPPORT_ABSTRACT_ASSEMBLY
67 #define SUPPORT_ASSEMBLY
68 #undef SUPPORT_OPTO_ASSEMBLY // Can't activate. In PRODUCT, many dump methods are missing.
69 #undef SUPPORT_DATA_STRUCTS // Of limited use. In PRODUCT, many print methods are empty.
70 #else
71 #define SUPPORT_ABSTRACT_ASSEMBLY
72 #define SUPPORT_ASSEMBLY
73 #define SUPPORT_OPTO_ASSEMBLY
74 #define SUPPORT_DATA_STRUCTS
75 #endif
76 #if defined(SUPPORT_ASSEMBLY) && !defined(SUPPORT_ABSTRACT_ASSEMBLY)
77 #define SUPPORT_ABSTRACT_ASSEMBLY
78 #endif
79
80 // This file holds all globally used constants & types, class (forward)
81 // declarations and a few frequently used utility functions.
82
83 // Declare the named class to be noncopyable. This macro must be followed by
84 // a semi-colon. The macro provides deleted declarations for the class's copy
85 // constructor and assignment operator. Because these operations are deleted,
86 // they cannot be defined and potential callers will fail to compile.
87 #define NONCOPYABLE(C) C(C const&) = delete; C& operator=(C const&) = delete /* next token must be ; */
88
89
90 //----------------------------------------------------------------------------------------------------
91 // Printf-style formatters for fixed- and variable-width types as pointers and
92 // integers. These are derived from the definitions in inttypes.h. If the platform
93 // doesn't provide appropriate definitions, they should be provided in
94 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp)
95
96 // Guide to the suffixes used in the format specifiers for integers:
97 // - print the decimal value: 745565
98 // _X - print as hexadecimal, without leading 0s: 0x12345
99 // _X_0 - print as hexadecimal, with leading 0s: 0x00012345
100 // _W(w) - prints w sized string with the given value right
101 // adjusted. Use -w to print left adjusted.
102 //
103 // Note that the PTR format specifiers print using 0x with leading zeros,
104 // just like the _X_0 version for integers.
105
106 // Format 8-bit quantities.
107 #define INT8_FORMAT_X_0 "0x%02" PRIx8
108 #define UINT8_FORMAT_X_0 "0x%02" PRIx8
109
110 // Format 16-bit quantities.
111 #define INT16_FORMAT_X_0 "0x%04" PRIx16
112 #define UINT16_FORMAT_X_0 "0x%04" PRIx16
113
114 // Format 32-bit quantities.
115 #define INT32_FORMAT "%" PRId32
116 #define INT32_FORMAT_X "0x%" PRIx32
117 #define INT32_FORMAT_X_0 "0x%08" PRIx32
118 #define INT32_FORMAT_W(width) "%" #width PRId32
119 #define UINT32_FORMAT "%" PRIu32
120 #define UINT32_FORMAT_X "0x%" PRIx32
121 #define UINT32_FORMAT_X_0 "0x%08" PRIx32
122 #define UINT32_FORMAT_W(width) "%" #width PRIu32
123
124 // Format 64-bit quantities.
125 #define INT64_FORMAT "%" PRId64
126 #define INT64_PLUS_FORMAT "%+" PRId64
127 #define INT64_FORMAT_X "0x%" PRIx64
128 #define INT64_FORMAT_X_0 "0x%016" PRIx64
129 #define INT64_FORMAT_W(width) "%" #width PRId64
130 #define UINT64_FORMAT "%" PRIu64
131 #define UINT64_FORMAT_X "0x%" PRIx64
132 #define UINT64_FORMAT_X_0 "0x%016" PRIx64
133 #define UINT64_FORMAT_W(width) "%" #width PRIu64
134
135 // Format integers which change size between 32- and 64-bit.
136 #define SSIZE_FORMAT "%" PRIdPTR
137 #define SSIZE_PLUS_FORMAT "%+" PRIdPTR
138 #define SSIZE_FORMAT_W(width) "%" #width PRIdPTR
139 #define SIZE_FORMAT "%" PRIuPTR
140 #define SIZE_FORMAT_X "0x%" PRIxPTR
141 #ifdef _LP64
142 #define SIZE_FORMAT_X_0 "0x%016" PRIxPTR
143 #else
144 #define SIZE_FORMAT_X_0 "0x%08" PRIxPTR
145 #endif
146 #define SIZE_FORMAT_W(width) "%" #width PRIuPTR
147
148 #define INTX_FORMAT "%" PRIdPTR
149 #define INTX_FORMAT_X "0x%" PRIxPTR
150 #define INTX_FORMAT_W(width) "%" #width PRIdPTR
151 #define UINTX_FORMAT "%" PRIuPTR
152 #define UINTX_FORMAT_X "0x%" PRIxPTR
153 #define UINTX_FORMAT_W(width) "%" #width PRIuPTR
154
155 // Format jlong, if necessary
156 #ifndef JLONG_FORMAT
157 #define JLONG_FORMAT INT64_FORMAT
158 #endif
159 #ifndef JLONG_FORMAT_W
160 #define JLONG_FORMAT_W(width) INT64_FORMAT_W(width)
161 #endif
162 #ifndef JULONG_FORMAT
163 #define JULONG_FORMAT UINT64_FORMAT
164 #endif
165 #ifndef JULONG_FORMAT_X
166 #define JULONG_FORMAT_X UINT64_FORMAT_X
167 #endif
168
169 // Format pointers which change size between 32- and 64-bit.
170 #ifdef _LP64
171 #define INTPTR_FORMAT "0x%016" PRIxPTR
172 #define PTR_FORMAT "0x%016" PRIxPTR
173 #else // !_LP64
174 #define INTPTR_FORMAT "0x%08" PRIxPTR
175 #define PTR_FORMAT "0x%08" PRIxPTR
176 #endif // _LP64
177
178 // Convert pointer to intptr_t, for use in printing pointers.
179 inline intptr_t p2i(const volatile void* p) {
180 return (intptr_t) p;
181 }
182
183 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false")
184
185 //----------------------------------------------------------------------------------------------------
186 // Forbid the use of various C library functions.
187 // Some of these have os:: replacements that should normally be used instead.
188 // Others are considered security concerns, with preferred alternatives.
189
190 FORBID_C_FUNCTION(void exit(int), "use os::exit");
191 FORBID_C_FUNCTION(void _exit(int), "use os::exit");
192 FORBID_C_FUNCTION(char* strerror(int), "use os::strerror");
193 FORBID_C_FUNCTION(char* strtok(char*, const char*), "use strtok_r");
194 FORBID_C_FUNCTION(int sprintf(char*, const char*, ...), "use os::snprintf");
195 FORBID_C_FUNCTION(int vsprintf(char*, const char*, va_list), "use os::vsnprintf");
196 FORBID_C_FUNCTION(int vsnprintf(char*, size_t, const char*, va_list), "use os::vsnprintf");
197
198 // All of the following functions return raw C-heap pointers (sometimes as an option, e.g. realpath or getwd)
199 // or, in case of free(), take raw C-heap pointers. Don't use them unless you are really sure you must.
200 FORBID_C_FUNCTION(void* malloc(size_t size), "use os::malloc");
201 FORBID_C_FUNCTION(void* calloc(size_t nmemb, size_t size), "use os::malloc and zero out manually");
202 FORBID_C_FUNCTION(void free(void *ptr), "use os::free");
203 FORBID_C_FUNCTION(void* realloc(void *ptr, size_t size), "use os::realloc");
204 FORBID_C_FUNCTION(char* strdup(const char *s), "use os::strdup");
205 FORBID_C_FUNCTION(char* strndup(const char *s, size_t n), "don't use");
206 FORBID_C_FUNCTION(int posix_memalign(void **memptr, size_t alignment, size_t size), "don't use");
207 FORBID_C_FUNCTION(void* aligned_alloc(size_t alignment, size_t size), "don't use");
208 FORBID_C_FUNCTION(char* realpath(const char* path, char* resolved_path), "use os::Posix::realpath");
209 FORBID_C_FUNCTION(char* get_current_dir_name(void), "use os::get_current_directory()");
210 FORBID_C_FUNCTION(char* getwd(char *buf), "use os::get_current_directory()");
211 FORBID_C_FUNCTION(wchar_t* wcsdup(const wchar_t *s), "don't use");
212 FORBID_C_FUNCTION(void* reallocf(void *ptr, size_t size), "don't use");
213
214 //----------------------------------------------------------------------------------------------------
215 // Constants
216
217 const int LogBytesPerShort = 1;
218 const int LogBytesPerInt = 2;
219 #ifdef _LP64
220 const int LogBytesPerWord = 3;
221 #else
222 const int LogBytesPerWord = 2;
223 #endif
224 const int LogBytesPerLong = 3;
225
226 const int BytesPerShort = 1 << LogBytesPerShort;
227 const int BytesPerInt = 1 << LogBytesPerInt;
228 const int BytesPerWord = 1 << LogBytesPerWord;
229 const int BytesPerLong = 1 << LogBytesPerLong;
230
231 const int LogBitsPerByte = 3;
232 const int LogBitsPerShort = LogBitsPerByte + LogBytesPerShort;
233 const int LogBitsPerInt = LogBitsPerByte + LogBytesPerInt;
234 const int LogBitsPerWord = LogBitsPerByte + LogBytesPerWord;
235 const int LogBitsPerLong = LogBitsPerByte + LogBytesPerLong;
236
237 const int BitsPerByte = 1 << LogBitsPerByte;
238 const int BitsPerShort = 1 << LogBitsPerShort;
239 const int BitsPerInt = 1 << LogBitsPerInt;
240 const int BitsPerWord = 1 << LogBitsPerWord;
241 const int BitsPerLong = 1 << LogBitsPerLong;
242
243 const int WordAlignmentMask = (1 << LogBytesPerWord) - 1;
244 const int LongAlignmentMask = (1 << LogBytesPerLong) - 1;
245
246 const int oopSize = sizeof(char*); // Full-width oop
247 extern int heapOopSize; // Oop within a java object
248 const int wordSize = sizeof(char*);
249 const int longSize = sizeof(jlong);
250 const int jintSize = sizeof(jint);
251 const int size_tSize = sizeof(size_t);
252
253 const int BytesPerOop = BytesPerWord; // Full-width oop
254
255 extern int LogBytesPerHeapOop; // Oop within a java object
256 extern int LogBitsPerHeapOop;
257 extern int BytesPerHeapOop;
258 extern int BitsPerHeapOop;
259
260 const int BitsPerJavaInteger = 32;
261 const int BitsPerJavaLong = 64;
262 const int BitsPerSize_t = size_tSize * BitsPerByte;
263
264 // Size of a char[] needed to represent a jint as a string in decimal.
265 const int jintAsStringSize = 12;
266
267 // An opaque type, so that HeapWord* can be a generic pointer into the heap.
268 // We require that object sizes be measured in units of heap words (e.g.
269 // pointer-sized values), so that given HeapWord* hw,
270 // hw += oop(hw)->foo();
271 // works, where foo is a method (like size or scavenge) that returns the
272 // object size.
273 class HeapWordImpl; // Opaque, never defined.
274 typedef HeapWordImpl* HeapWord;
275
276 // Analogous opaque struct for metadata allocated from metaspaces.
277 class MetaWordImpl; // Opaque, never defined.
278 typedef MetaWordImpl* MetaWord;
279
280 // HeapWordSize must be 2^LogHeapWordSize.
281 const int HeapWordSize = sizeof(HeapWord);
282 #ifdef _LP64
283 const int LogHeapWordSize = 3;
284 #else
285 const int LogHeapWordSize = 2;
286 #endif
287 const int HeapWordsPerLong = BytesPerLong / HeapWordSize;
288 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize;
289
290 // The minimum number of native machine words necessary to contain "byte_size"
291 // bytes.
292 inline size_t heap_word_size(size_t byte_size) {
293 return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize;
294 }
295
296 inline jfloat jfloat_cast(jint x);
297 inline jdouble jdouble_cast(jlong x);
298
299 //-------------------------------------------
300 // Constant for jlong (standardized by C++11)
301
302 // Build a 64bit integer constant
303 #define CONST64(x) (x ## LL)
304 #define UCONST64(x) (x ## ULL)
305
306 const jlong min_jlong = CONST64(0x8000000000000000);
307 const jlong max_jlong = CONST64(0x7fffffffffffffff);
308
309 //-------------------------------------------
310 // Constant for jdouble
311 const jlong min_jlongDouble = CONST64(0x0000000000000001);
312 const jdouble min_jdouble = jdouble_cast(min_jlongDouble);
313 const jlong max_jlongDouble = CONST64(0x7fefffffffffffff);
314 const jdouble max_jdouble = jdouble_cast(max_jlongDouble);
315
316 const size_t K = 1024;
317 const size_t M = K*K;
318 const size_t G = M*K;
319 const size_t HWperKB = K / sizeof(HeapWord);
320
321 // Constants for converting from a base unit to milli-base units. For
322 // example from seconds to milliseconds and microseconds
323
324 const int MILLIUNITS = 1000; // milli units per base unit
325 const int MICROUNITS = 1000000; // micro units per base unit
326 const int NANOUNITS = 1000000000; // nano units per base unit
327 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS;
328
329 const jlong NANOSECS_PER_SEC = CONST64(1000000000);
330 const jint NANOSECS_PER_MILLISEC = 1000000;
331
332
333 // Unit conversion functions
334 // The caller is responsible for considering overflow.
335
336 inline int64_t nanos_to_millis(int64_t nanos) {
337 return nanos / NANOUNITS_PER_MILLIUNIT;
338 }
339 inline int64_t millis_to_nanos(int64_t millis) {
340 return millis * NANOUNITS_PER_MILLIUNIT;
341 }
342
343 // Proper units routines try to maintain at least three significant digits.
344 // In worst case, it would print five significant digits with lower prefix.
345 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow,
346 // and therefore we need to be careful.
347
348 inline const char* proper_unit_for_byte_size(size_t s) {
349 #ifdef _LP64
350 if (s >= 100*G) {
351 return "G";
352 }
353 #endif
354 if (s >= 100*M) {
355 return "M";
356 } else if (s >= 100*K) {
357 return "K";
358 } else {
359 return "B";
360 }
361 }
362
363 template <class T>
364 inline T byte_size_in_proper_unit(T s) {
365 #ifdef _LP64
366 if (s >= 100*G) {
367 return (T)(s/G);
368 }
369 #endif
370 if (s >= 100*M) {
371 return (T)(s/M);
372 } else if (s >= 100*K) {
373 return (T)(s/K);
374 } else {
375 return s;
376 }
377 }
378
379 #define PROPERFMT SIZE_FORMAT "%s"
380 #define PROPERFMTARGS(s) byte_size_in_proper_unit(s), proper_unit_for_byte_size(s)
381
382 inline const char* exact_unit_for_byte_size(size_t s) {
383 #ifdef _LP64
384 if (s >= G && (s % G) == 0) {
385 return "G";
386 }
387 #endif
388 if (s >= M && (s % M) == 0) {
389 return "M";
390 }
391 if (s >= K && (s % K) == 0) {
392 return "K";
393 }
394 return "B";
395 }
396
397 inline size_t byte_size_in_exact_unit(size_t s) {
398 #ifdef _LP64
399 if (s >= G && (s % G) == 0) {
400 return s / G;
401 }
402 #endif
403 if (s >= M && (s % M) == 0) {
404 return s / M;
405 }
406 if (s >= K && (s % K) == 0) {
407 return s / K;
408 }
409 return s;
410 }
411
412 #define EXACTFMT SIZE_FORMAT "%s"
413 #define EXACTFMTARGS(s) byte_size_in_exact_unit(s), exact_unit_for_byte_size(s)
414
415 // Memory size transition formatting.
416
417 #define HEAP_CHANGE_FORMAT "%s: " SIZE_FORMAT "K(" SIZE_FORMAT "K)->" SIZE_FORMAT "K(" SIZE_FORMAT "K)"
418
419 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \
420 (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K
421
422 //----------------------------------------------------------------------------------------------------
423 // VM type definitions
424
425 // intx and uintx are the 'extended' int and 'extended' unsigned int types;
426 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.
427
428 typedef intptr_t intx;
429 typedef uintptr_t uintx;
430
431 const intx min_intx = (intx)1 << (sizeof(intx)*BitsPerByte-1);
432 const intx max_intx = (uintx)min_intx - 1;
433 const uintx max_uintx = (uintx)-1;
434
435 // Table of values:
436 // sizeof intx 4 8
437 // min_intx 0x80000000 0x8000000000000000
438 // max_intx 0x7FFFFFFF 0x7FFFFFFFFFFFFFFF
439 // max_uintx 0xFFFFFFFF 0xFFFFFFFFFFFFFFFF
440
441 typedef unsigned int uint; NEEDS_CLEANUP
442
443 //----------------------------------------------------------------------------------------------------
444 // Java type definitions
445
446 // All kinds of 'plain' byte addresses
447 typedef signed char s_char;
448 typedef unsigned char u_char;
449 typedef u_char* address;
450
451 // Pointer subtraction.
452 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have
453 // the range we might need to find differences from one end of the heap
454 // to the other.
455 // A typical use might be:
456 // if (pointer_delta(end(), top()) >= size) {
457 // // enough room for an object of size
458 // ...
459 // and then additions like
460 // ... top() + size ...
461 // are safe because we know that top() is at least size below end().
462 inline size_t pointer_delta(const volatile void* left,
463 const volatile void* right,
464 size_t element_size) {
465 assert(left >= right, "avoid underflow - left: " PTR_FORMAT " right: " PTR_FORMAT, p2i(left), p2i(right));
466 return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;
467 }
468
469 // A version specialized for HeapWord*'s.
470 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {
471 return pointer_delta(left, right, sizeof(HeapWord));
472 }
473 // A version specialized for MetaWord*'s.
474 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) {
475 return pointer_delta(left, right, sizeof(MetaWord));
476 }
477
478 // pointer_delta_as_int is called to do pointer subtraction for nearby pointers that
479 // returns a non-negative int, usually used as a size of a code buffer range.
480 // This scales to sizeof(T).
481 template <typename T>
482 inline int pointer_delta_as_int(const volatile T* left, const volatile T* right) {
483 size_t delta = pointer_delta(left, right, sizeof(T));
484 assert(delta <= size_t(INT_MAX), "pointer delta out of range: %zu", delta);
485 return static_cast<int>(delta);
486 }
487
488 //
489 // ANSI C++ does not allow casting from one pointer type to a function pointer
490 // directly without at best a warning. This macro accomplishes it silently
491 // In every case that is present at this point the value be cast is a pointer
492 // to a C linkage function. In some case the type used for the cast reflects
493 // that linkage and a picky compiler would not complain. In other cases because
494 // there is no convenient place to place a typedef with extern C linkage (i.e
495 // a platform dependent header file) it doesn't. At this point no compiler seems
496 // picky enough to catch these instances (which are few). It is possible that
497 // using templates could fix these for all cases. This use of templates is likely
498 // so far from the middle of the road that it is likely to be problematic in
499 // many C++ compilers.
500 //
501 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value))
502 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((uintptr_t)(func_ptr)))
503
504 // Need the correct linkage to call qsort without warnings
505 extern "C" {
506 typedef int (*_sort_Fn)(const void *, const void *);
507 }
508
509 // Additional Java basic types
510
511 typedef uint8_t jubyte;
512 typedef uint16_t jushort;
513 typedef uint32_t juint;
514 typedef uint64_t julong;
515
516 // Unsigned byte types for os and stream.hpp
517
518 // Unsigned one, two, four and eight byte quantities used for describing
519 // the .class file format. See JVM book chapter 4.
520
521 typedef jubyte u1;
522 typedef jushort u2;
523 typedef juint u4;
524 typedef julong u8;
525
526 const jubyte max_jubyte = (jubyte)-1; // 0xFF largest jubyte
527 const jushort max_jushort = (jushort)-1; // 0xFFFF largest jushort
528 const juint max_juint = (juint)-1; // 0xFFFFFFFF largest juint
529 const julong max_julong = (julong)-1; // 0xFF....FF largest julong
530
531 typedef jbyte s1;
532 typedef jshort s2;
533 typedef jint s4;
534 typedef jlong s8;
535
536 const jbyte min_jbyte = -(1 << 7); // smallest jbyte
537 const jbyte max_jbyte = (1 << 7) - 1; // largest jbyte
538 const jshort min_jshort = -(1 << 15); // smallest jshort
539 const jshort max_jshort = (1 << 15) - 1; // largest jshort
540
541 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
542 const jint max_jint = (juint)min_jint - 1; // 0x7FFFFFFF == largest jint
543
544 const jint min_jintFloat = (jint)(0x00000001);
545 const jfloat min_jfloat = jfloat_cast(min_jintFloat);
546 const jint max_jintFloat = (jint)(0x7f7fffff);
547 const jfloat max_jfloat = jfloat_cast(max_jintFloat);
548
549 //----------------------------------------------------------------------------------------------------
550 // JVM spec restrictions
551
552 const int max_method_code_size = 64*K - 1; // JVM spec, 2nd ed. section 4.8.1 (p.134)
553
554 //----------------------------------------------------------------------------------------------------
555 // old CDS options
556 extern bool RequireSharedSpaces;
557 extern "C" {
558 // Make sure UseSharedSpaces is accessible to the serviceability agent.
559 extern JNIEXPORT jboolean UseSharedSpaces;
560 }
561
562 //----------------------------------------------------------------------------------------------------
563 // Object alignment, in units of HeapWords.
564 //
565 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and
566 // reference fields can be naturally aligned.
567
568 extern int MinObjAlignment;
569 extern int MinObjAlignmentInBytes;
570 extern int MinObjAlignmentInBytesMask;
571
572 extern int LogMinObjAlignment;
573 extern int LogMinObjAlignmentInBytes;
574
575 // Maximal size of heap where unscaled compression can be used. Also upper bound
576 // for heap placement: 4GB.
577 const uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
578 // Maximal size of heap where compressed oops can be used. Also upper bound for heap
579 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes.
580 extern uint64_t OopEncodingHeapMax;
581
582 // Machine dependent stuff
583
584 // The maximum size of the code cache. Can be overridden by targets.
585 #define CODE_CACHE_SIZE_LIMIT (2*G)
586 // Allow targets to reduce the default size of the code cache.
587 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT
588
589 #include CPU_HEADER(globalDefinitions)
590
591 // To assure the IRIW property on processors that are not multiple copy
592 // atomic, sync instructions must be issued between volatile reads to
593 // assure their ordering, instead of after volatile stores.
594 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models"
595 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge)
596 #ifdef CPU_MULTI_COPY_ATOMIC
597 // Not needed.
598 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false;
599 #else
600 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment.
601 // Final decision is subject to JEP 188: Java Memory Model Update.
602 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false);
603 #endif
604
605 // The expected size in bytes of a cache line.
606 #ifndef DEFAULT_CACHE_LINE_SIZE
607 #error "Platform should define DEFAULT_CACHE_LINE_SIZE"
608 #endif
609
610 // The default padding size for data structures to avoid false sharing.
611 #ifndef DEFAULT_PADDING_SIZE
612 #error "Platform should define DEFAULT_PADDING_SIZE"
613 #endif
614
615
616 //----------------------------------------------------------------------------------------------------
617 // Utility macros for compilers
618 // used to silence compiler warnings
619
620 #define Unused_Variable(var) var
621
622
623 //----------------------------------------------------------------------------------------------------
624 // Prototyping
625 // "Code Missing Here" macro, un-define when integrating back from prototyping stage and break
626 // compilation on purpose (i.e. "forget me not")
627 #define PROTOTYPE
628 #ifdef PROTOTYPE
629 #define CMH(m)
630 #endif
631
632 //----------------------------------------------------------------------------------------------------
633 // Miscellaneous
634
635 // 6302670 Eliminate Hotspot __fabsf dependency
636 // All fabs() callers should call this function instead, which will implicitly
637 // convert the operand to double, avoiding a dependency on __fabsf which
638 // doesn't exist in early versions of Solaris 8.
639 inline double fabsd(double value) {
640 return fabs(value);
641 }
642
643 // Returns numerator/denominator as percentage value from 0 to 100. If denominator
644 // is zero, return 0.0.
645 template<typename T>
646 inline double percent_of(T numerator, T denominator) {
647 return denominator != 0 ? (double)numerator / (double)denominator * 100.0 : 0.0;
648 }
649
650 //----------------------------------------------------------------------------------------------------
651 // Special casts
652 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern
653 typedef union {
654 jfloat f;
655 jint i;
656 } FloatIntConv;
657
658 typedef union {
659 jdouble d;
660 jlong l;
661 julong ul;
662 } DoubleLongConv;
663
664 inline jint jint_cast (jfloat x) { return ((FloatIntConv*)&x)->i; }
665 inline jfloat jfloat_cast (jint x) { return ((FloatIntConv*)&x)->f; }
666
667 inline jlong jlong_cast (jdouble x) { return ((DoubleLongConv*)&x)->l; }
668 inline julong julong_cast (jdouble x) { return ((DoubleLongConv*)&x)->ul; }
669 inline jdouble jdouble_cast (jlong x) { return ((DoubleLongConv*)&x)->d; }
670
671 inline jint low (jlong value) { return jint(value); }
672 inline jint high(jlong value) { return jint(value >> 32); }
673
674 // the fancy casts are a hopefully portable way
675 // to do unsigned 32 to 64 bit type conversion
676 inline void set_low (jlong* value, jint low ) { *value &= (jlong)0xffffffff << 32;
677 *value |= (jlong)(julong)(juint)low; }
678
679 inline void set_high(jlong* value, jint high) { *value &= (jlong)(julong)(juint)0xffffffff;
680 *value |= (jlong)high << 32; }
681
682 inline jlong jlong_from(jint h, jint l) {
683 jlong result = 0; // initialization to avoid warning
684 set_high(&result, h);
685 set_low(&result, l);
686 return result;
687 }
688
689 union jlong_accessor {
690 jint words[2];
691 jlong long_value;
692 };
693
694 void basic_types_init(); // cannot define here; uses assert
695
696
697 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
698 enum BasicType : u1 {
699 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS.
700 T_BOOLEAN = JVM_T_BOOLEAN,
701 T_CHAR = JVM_T_CHAR,
702 T_FLOAT = JVM_T_FLOAT,
703 T_DOUBLE = JVM_T_DOUBLE,
704 T_BYTE = JVM_T_BYTE,
705 T_SHORT = JVM_T_SHORT,
706 T_INT = JVM_T_INT,
707 T_LONG = JVM_T_LONG,
708 // The remaining values are not part of any standard.
709 // T_OBJECT and T_VOID denote two more semantic choices
710 // for method return values.
711 // T_OBJECT and T_ARRAY describe signature syntax.
712 // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe
713 // internal references within the JVM as if they were Java
714 // types in their own right.
715 T_OBJECT = 12,
716 T_ARRAY = 13,
717 T_PRIMITIVE_OBJECT = 14, // Not a true BasicType, only use in headers of flat arrays
718 T_VOID = 15,
719 T_ADDRESS = 16,
720 T_NARROWOOP = 17,
721 T_METADATA = 18,
722 T_NARROWKLASS = 19,
723 T_CONFLICT = 20, // for stack value type with conflicting contents
724 T_ILLEGAL = 99
725 };
726
727 #define SIGNATURE_TYPES_DO(F, N) \
728 F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N) \
729 F(JVM_SIGNATURE_CHAR, T_CHAR, N) \
730 F(JVM_SIGNATURE_FLOAT, T_FLOAT, N) \
731 F(JVM_SIGNATURE_DOUBLE, T_DOUBLE, N) \
732 F(JVM_SIGNATURE_BYTE, T_BYTE, N) \
733 F(JVM_SIGNATURE_SHORT, T_SHORT, N) \
734 F(JVM_SIGNATURE_INT, T_INT, N) \
735 F(JVM_SIGNATURE_LONG, T_LONG, N) \
736 F(JVM_SIGNATURE_CLASS, T_OBJECT, N) \
737 F(JVM_SIGNATURE_ARRAY, T_ARRAY, N) \
738 F(JVM_SIGNATURE_PRIMITIVE_OBJECT, T_PRIMITIVE_OBJECT, N) \
739 F(JVM_SIGNATURE_VOID, T_VOID, N) \
740 /*end*/
741
742 inline bool is_java_type(BasicType t) {
743 return T_BOOLEAN <= t && t <= T_VOID;
744 }
745
746 inline bool is_java_primitive(BasicType t) {
747 return T_BOOLEAN <= t && t <= T_LONG;
748 }
749
750 inline bool is_subword_type(BasicType t) {
751 // these guys are processed exactly like T_INT in calling sequences:
752 return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);
753 }
754
755 inline bool is_signed_subword_type(BasicType t) {
756 return (t == T_BYTE || t == T_SHORT);
757 }
758
759 inline bool is_unsigned_subword_type(BasicType t) {
760 return (t == T_BOOLEAN || t == T_CHAR);
761 }
762
763 inline bool is_double_word_type(BasicType t) {
764 return (t == T_DOUBLE || t == T_LONG);
765 }
766
767 inline bool is_reference_type(BasicType t, bool include_narrow_oop = false) {
768 // TODO 8325106 Remove the last occurences of T_PRIMITIVE_OBJECT
769 return (t == T_OBJECT || t == T_ARRAY || t == T_PRIMITIVE_OBJECT || (include_narrow_oop && t == T_NARROWOOP));
770 }
771
772 inline bool is_integral_type(BasicType t) {
773 return is_subword_type(t) || t == T_INT || t == T_LONG;
774 }
775
776 inline bool is_non_subword_integral_type(BasicType t) {
777 return t == T_INT || t == T_LONG;
778 }
779
780 inline bool is_floating_point_type(BasicType t) {
781 return (t == T_FLOAT || t == T_DOUBLE);
782 }
783
784 extern char type2char_tab[T_CONFLICT+1]; // Map a BasicType to a jchar
785 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }
786 extern int type2size[T_CONFLICT+1]; // Map BasicType to result stack elements
787 extern const char* type2name_tab[T_CONFLICT+1]; // Map a BasicType to a char*
788 extern BasicType name2type(const char* name);
789
790 const char* type2name(BasicType t);
791
792 inline jlong max_signed_integer(BasicType bt) {
793 if (bt == T_INT) {
794 return max_jint;
795 }
796 assert(bt == T_LONG, "unsupported");
797 return max_jlong;
798 }
799
800 inline jlong min_signed_integer(BasicType bt) {
801 if (bt == T_INT) {
802 return min_jint;
803 }
804 assert(bt == T_LONG, "unsupported");
805 return min_jlong;
806 }
807
808 // Auxiliary math routines
809 // least common multiple
810 extern size_t lcm(size_t a, size_t b);
811
812
813 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
814 enum BasicTypeSize {
815 T_BOOLEAN_size = 1,
816 T_CHAR_size = 1,
817 T_FLOAT_size = 1,
818 T_DOUBLE_size = 2,
819 T_BYTE_size = 1,
820 T_SHORT_size = 1,
821 T_INT_size = 1,
822 T_LONG_size = 2,
823 T_OBJECT_size = 1,
824 T_ARRAY_size = 1,
825 T_NARROWOOP_size = 1,
826 T_NARROWKLASS_size = 1,
827 T_VOID_size = 0,
828 T_PRIMITIVE_OBJECT_size = 1
829 };
830
831 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc.
832 inline int parameter_type_word_count(BasicType t) {
833 if (is_double_word_type(t)) return 2;
834 assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please");
835 assert(type2size[t] == 1, "must be");
836 return 1;
837 }
838
839 // maps a BasicType to its instance field storage type:
840 // all sub-word integral types are widened to T_INT
841 extern BasicType type2field[T_CONFLICT+1];
842 extern BasicType type2wfield[T_CONFLICT+1];
843
844
845 // size in bytes
846 enum ArrayElementSize {
847 T_BOOLEAN_aelem_bytes = 1,
848 T_CHAR_aelem_bytes = 2,
849 T_FLOAT_aelem_bytes = 4,
850 T_DOUBLE_aelem_bytes = 8,
851 T_BYTE_aelem_bytes = 1,
852 T_SHORT_aelem_bytes = 2,
853 T_INT_aelem_bytes = 4,
854 T_LONG_aelem_bytes = 8,
855 #ifdef _LP64
856 T_OBJECT_aelem_bytes = 8,
857 T_ARRAY_aelem_bytes = 8,
858 T_PRIMITIVE_OBJECT_aelem_bytes = 8,
859 #else
860 T_OBJECT_aelem_bytes = 4,
861 T_ARRAY_aelem_bytes = 4,
862 T_PRIMITIVE_OBJECT_aelem_bytes = 4,
863 #endif
864 T_NARROWOOP_aelem_bytes = 4,
865 T_NARROWKLASS_aelem_bytes = 4,
866 T_VOID_aelem_bytes = 0
867 };
868
869 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element
870 #ifdef ASSERT
871 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts
872 #else
873 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; }
874 #endif
875
876 inline bool same_type_or_subword_size(BasicType t1, BasicType t2) {
877 return (t1 == t2) || (is_subword_type(t1) && type2aelembytes(t1) == type2aelembytes(t2));
878 }
879
880 // JavaValue serves as a container for arbitrary Java values.
881
882 class JavaValue {
883
884 public:
885 typedef union JavaCallValue {
886 jfloat f;
887 jdouble d;
888 jint i;
889 jlong l;
890 jobject h;
891 oopDesc* o;
892 } JavaCallValue;
893
894 private:
895 BasicType _type;
896 JavaCallValue _value;
897
898 public:
899 JavaValue(BasicType t = T_ILLEGAL) { _type = t; }
900
901 JavaValue(jfloat value) {
902 _type = T_FLOAT;
903 _value.f = value;
904 }
905
906 JavaValue(jdouble value) {
907 _type = T_DOUBLE;
908 _value.d = value;
909 }
910
911 jfloat get_jfloat() const { return _value.f; }
912 jdouble get_jdouble() const { return _value.d; }
913 jint get_jint() const { return _value.i; }
914 jlong get_jlong() const { return _value.l; }
915 jobject get_jobject() const { return _value.h; }
916 oopDesc* get_oop() const { return _value.o; }
917 JavaCallValue* get_value_addr() { return &_value; }
918 BasicType get_type() const { return _type; }
919
920 void set_jfloat(jfloat f) { _value.f = f;}
921 void set_jdouble(jdouble d) { _value.d = d;}
922 void set_jint(jint i) { _value.i = i;}
923 void set_jlong(jlong l) { _value.l = l;}
924 void set_jobject(jobject h) { _value.h = h;}
925 void set_oop(oopDesc* o) { _value.o = o;}
926 void set_type(BasicType t) { _type = t; }
927
928 jboolean get_jboolean() const { return (jboolean) (_value.i);}
929 jbyte get_jbyte() const { return (jbyte) (_value.i);}
930 jchar get_jchar() const { return (jchar) (_value.i);}
931 jshort get_jshort() const { return (jshort) (_value.i);}
932
933 };
934
935
936 // TosState describes the top-of-stack state before and after the execution of
937 // a bytecode or method. The top-of-stack value may be cached in one or more CPU
938 // registers. The TosState corresponds to the 'machine representation' of this cached
939 // value. There's 4 states corresponding to the JAVA types int, long, float & double
940 // as well as a 5th state in case the top-of-stack value is actually on the top
941 // of stack (in memory) and thus not cached. The atos state corresponds to the itos
942 // state when it comes to machine representation but is used separately for (oop)
943 // type specific operations (e.g. verification code).
944
945 enum TosState { // describes the tos cache contents
946 btos = 0, // byte, bool tos cached
947 ztos = 1, // byte, bool tos cached
948 ctos = 2, // char tos cached
949 stos = 3, // short tos cached
950 itos = 4, // int tos cached
951 ltos = 5, // long tos cached
952 ftos = 6, // float tos cached
953 dtos = 7, // double tos cached
954 atos = 8, // object cached
955 vtos = 9, // tos not cached,
956 number_of_states,
957 ilgl // illegal state: should not occur
958 };
959
960
961 inline TosState as_TosState(BasicType type) {
962 switch (type) {
963 case T_BYTE : return btos;
964 case T_BOOLEAN: return ztos;
965 case T_CHAR : return ctos;
966 case T_SHORT : return stos;
967 case T_INT : return itos;
968 case T_LONG : return ltos;
969 case T_FLOAT : return ftos;
970 case T_DOUBLE : return dtos;
971 case T_VOID : return vtos;
972 case T_ARRAY : // fall through
973 case T_OBJECT : return atos;
974 default : return ilgl;
975 }
976 }
977
978 inline BasicType as_BasicType(TosState state) {
979 switch (state) {
980 case btos : return T_BYTE;
981 case ztos : return T_BOOLEAN;
982 case ctos : return T_CHAR;
983 case stos : return T_SHORT;
984 case itos : return T_INT;
985 case ltos : return T_LONG;
986 case ftos : return T_FLOAT;
987 case dtos : return T_DOUBLE;
988 case atos : return T_OBJECT;
989 case vtos : return T_VOID;
990 default : return T_ILLEGAL;
991 }
992 }
993
994
995 // Helper function to convert BasicType info into TosState
996 // Note: Cannot define here as it uses global constant at the time being.
997 TosState as_TosState(BasicType type);
998
999
1000 // JavaThreadState keeps track of which part of the code a thread is executing in. This
1001 // information is needed by the safepoint code.
1002 //
1003 // There are 4 essential states:
1004 //
1005 // _thread_new : Just started, but not executed init. code yet (most likely still in OS init code)
1006 // _thread_in_native : In native code. This is a safepoint region, since all oops will be in jobject handles
1007 // _thread_in_vm : Executing in the vm
1008 // _thread_in_Java : Executing either interpreted or compiled Java code (or could be in a stub)
1009 //
1010 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in
1011 // a transition from one state to another. These extra states makes it possible for the safepoint code to
1012 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.
1013 //
1014 // Given a state, the xxxx_trans state can always be found by adding 1.
1015 //
1016 enum JavaThreadState {
1017 _thread_uninitialized = 0, // should never happen (missing initialization)
1018 _thread_new = 2, // just starting up, i.e., in process of being initialized
1019 _thread_new_trans = 3, // corresponding transition state (not used, included for completeness)
1020 _thread_in_native = 4, // running in native code
1021 _thread_in_native_trans = 5, // corresponding transition state
1022 _thread_in_vm = 6, // running in VM
1023 _thread_in_vm_trans = 7, // corresponding transition state
1024 _thread_in_Java = 8, // running in Java or in stub code
1025 _thread_in_Java_trans = 9, // corresponding transition state (not used, included for completeness)
1026 _thread_blocked = 10, // blocked in vm
1027 _thread_blocked_trans = 11, // corresponding transition state
1028 _thread_max_state = 12 // maximum thread state+1 - used for statistics allocation
1029 };
1030
1031 enum LockingMode {
1032 // Use only heavy monitors for locking
1033 LM_MONITOR = 0,
1034 // Legacy stack-locking, with monitors as 2nd tier
1035 LM_LEGACY = 1,
1036 // New lightweight locking, with monitors as 2nd tier
1037 LM_LIGHTWEIGHT = 2
1038 };
1039
1040 //----------------------------------------------------------------------------------------------------
1041 // Special constants for debugging
1042
1043 const jint badInt = -3; // generic "bad int" value
1044 const intptr_t badAddressVal = -2; // generic "bad address" value
1045 const intptr_t badOopVal = -1; // generic "bad oop" value
1046 const intptr_t badHeapOopVal = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC
1047 const int badStackSegVal = 0xCA; // value used to zap stack segments
1048 const int badHandleValue = 0xBC; // value used to zap vm handle area
1049 const int badResourceValue = 0xAB; // value used to zap resource area
1050 const int freeBlockPad = 0xBA; // value used to pad freed blocks.
1051 const int uninitBlockPad = 0xF1; // value used to zap newly malloc'd blocks.
1052 const juint uninitMetaWordVal= 0xf7f7f7f7; // value used to zap newly allocated metachunk
1053 const juint badHeapWordVal = 0xBAADBABE; // value used to zap heap after GC
1054 const juint badMetaWordVal = 0xBAADFADE; // value used to zap metadata heap after GC
1055 const int badCodeHeapNewVal= 0xCC; // value used to zap Code heap at allocation
1056 const int badCodeHeapFreeVal = 0xDD; // value used to zap Code heap at deallocation
1057 const intptr_t badDispHeaderDeopt = 0xDE0BD000; // value to fill unused displaced header during deoptimization
1058 const intptr_t badDispHeaderOSR = 0xDEAD05A0; // value to fill unused displaced header during OSR
1059
1060 // (These must be implemented as #defines because C++ compilers are
1061 // not obligated to inline non-integral constants!)
1062 #define badAddress ((address)::badAddressVal)
1063 #define badHeapWord (::badHeapWordVal)
1064
1065 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)
1066 const uint TASKQUEUE_SIZE = (NOT_LP64(1<<14) LP64_ONLY(1<<17));
1067
1068 //----------------------------------------------------------------------------------------------------
1069 // Utility functions for bitfield manipulations
1070
1071 const intptr_t AllBits = ~0; // all bits set in a word
1072 const intptr_t NoBits = 0; // no bits set in a word
1073 const jlong NoLongBits = 0; // no bits set in a long
1074 const intptr_t OneBit = 1; // only right_most bit set in a word
1075
1076 // get a word with the n.th or the right-most or left-most n bits set
1077 // (note: #define used only so that they can be used in enum constant definitions)
1078 #define nth_bit(n) (((n) >= BitsPerWord) ? 0 : (OneBit << (n)))
1079 #define right_n_bits(n) (nth_bit(n) - 1)
1080
1081 // bit-operations using a mask m
1082 inline void set_bits (intptr_t& x, intptr_t m) { x |= m; }
1083 inline void clear_bits (intptr_t& x, intptr_t m) { x &= ~m; }
1084 inline intptr_t mask_bits (intptr_t x, intptr_t m) { return x & m; }
1085 inline jlong mask_long_bits (jlong x, jlong m) { return x & m; }
1086 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }
1087
1088 // bit-operations using the n.th bit
1089 inline void set_nth_bit(intptr_t& x, int n) { set_bits (x, nth_bit(n)); }
1090 inline void clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }
1091 inline bool is_set_nth_bit(intptr_t x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }
1092
1093 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)
1094 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {
1095 return mask_bits(x >> start_bit_no, right_n_bits(field_length));
1096 }
1097
1098
1099 //----------------------------------------------------------------------------------------------------
1100 // Utility functions for integers
1101
1102 // Avoid use of global min/max macros which may cause unwanted double
1103 // evaluation of arguments.
1104 #ifdef max
1105 #undef max
1106 #endif
1107
1108 #ifdef min
1109 #undef min
1110 #endif
1111
1112 // It is necessary to use templates here. Having normal overloaded
1113 // functions does not work because it is necessary to provide both 32-
1114 // and 64-bit overloaded functions, which does not work, and having
1115 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)
1116 // will be even more error-prone than macros.
1117 template<class T> constexpr T MAX2(T a, T b) { return (a > b) ? a : b; }
1118 template<class T> constexpr T MIN2(T a, T b) { return (a < b) ? a : b; }
1119 template<class T> constexpr T MAX3(T a, T b, T c) { return MAX2(MAX2(a, b), c); }
1120 template<class T> constexpr T MIN3(T a, T b, T c) { return MIN2(MIN2(a, b), c); }
1121 template<class T> constexpr T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }
1122 template<class T> constexpr T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }
1123
1124 template<class T> inline T ABS(T x) { return (x > 0) ? x : -x; }
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 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 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 uabs(jlong n) { return uabs((julong)n); }
1157 static inline unsigned int uabs(int n) { return 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 ResourceHashtable
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 // TEMP!!!!
1344 // This should be removed after LW2 arrays are implemented (JDK-8220790).
1345 // It's an alias to (EnableValhalla && (FlatArrayElementMaxSize != 0)),
1346 // which is actually not 100% correct, but works for the current set of C1/C2
1347 // implementation and test cases.
1348 #define UseFlatArray (EnableValhalla && (FlatArrayElementMaxSize != 0))
1349 template<typename K> int primitive_compare(const K& k0, const K& k1) {
1350 return ((k0 < k1) ? -1 : (k0 == k1) ? 0 : 1);
1351 }
1352
1353 //----------------------------------------------------------------------------------------------------
1354
1355 // Allow use of C++ thread_local when approved - see JDK-8282469.
1356 #define APPROVED_CPP_THREAD_LOCAL thread_local
1357
1358 // Converts any type T to a reference type.
1359 template<typename T>
1360 std::add_rvalue_reference_t<T> declval() noexcept;
1361
1362 // Quickly test to make sure IEEE-754 subnormal numbers are correctly
1363 // handled.
1364 bool IEEE_subnormal_handling_OK();
1365
1366 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP