1 /*
2 * Copyright (c) 1997, 2021, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_UTILITIES_GLOBALDEFINITIONS_HPP
26 #define SHARE_UTILITIES_GLOBALDEFINITIONS_HPP
27
28 #include "utilities/compilerWarnings.hpp"
29 #include "utilities/debug.hpp"
30 #include "utilities/macros.hpp"
31
32 // Get constants like JVM_T_CHAR and JVM_SIGNATURE_INT, before pulling in <jvm.h>.
33 #include "classfile_constants.h"
34
35 #include COMPILER_HEADER(utilities/globalDefinitions)
36
37 #include <cstddef>
38
39 class oopDesc;
40
41 // Defaults for macros that might be defined per compiler.
42 #ifndef NOINLINE
43 #define NOINLINE
44 #endif
45 #ifndef ALWAYSINLINE
46 #define ALWAYSINLINE inline
47 #endif
48
49 #ifndef ATTRIBUTE_ALIGNED
50 #define ATTRIBUTE_ALIGNED(x)
51 #endif
52
53 #ifndef ATTRIBUTE_FLATTEN
54 #define ATTRIBUTE_FLATTEN
55 #endif
56
57 // These are #defines to selectively turn on/off the Print(Opto)Assembly
58 // capabilities. Choices should be led by a tradeoff between
59 // code size and improved supportability.
60 // if PRINT_ASSEMBLY then PRINT_ABSTRACT_ASSEMBLY must be true as well
61 // to have a fallback in case hsdis is not available.
62 #if defined(PRODUCT)
63 #define SUPPORT_ABSTRACT_ASSEMBLY
64 #define SUPPORT_ASSEMBLY
65 #undef SUPPORT_OPTO_ASSEMBLY // Can't activate. In PRODUCT, many dump methods are missing.
66 #undef SUPPORT_DATA_STRUCTS // Of limited use. In PRODUCT, many print methods are empty.
67 #else
68 #define SUPPORT_ABSTRACT_ASSEMBLY
69 #define SUPPORT_ASSEMBLY
70 #define SUPPORT_OPTO_ASSEMBLY
71 #define SUPPORT_DATA_STRUCTS
72 #endif
73 #if defined(SUPPORT_ASSEMBLY) && !defined(SUPPORT_ABSTRACT_ASSEMBLY)
74 #define SUPPORT_ABSTRACT_ASSEMBLY
75 #endif
76
77 // This file holds all globally used constants & types, class (forward)
78 // declarations and a few frequently used utility functions.
79
80 // Declare the named class to be noncopyable. This macro must be followed by
81 // a semi-colon. The macro provides deleted declarations for the class's copy
82 // constructor and assignment operator. Because these operations are deleted,
83 // they cannot be defined and potential callers will fail to compile.
84 #define NONCOPYABLE(C) C(C const&) = delete; C& operator=(C const&) = delete /* next token must be ; */
85
86
87 //----------------------------------------------------------------------------------------------------
88 // Printf-style formatters for fixed- and variable-width types as pointers and
89 // integers. These are derived from the definitions in inttypes.h. If the platform
90 // doesn't provide appropriate definitions, they should be provided in
91 // the compiler-specific definitions file (e.g., globalDefinitions_gcc.hpp)
92
93 #define BOOL_TO_STR(_b_) ((_b_) ? "true" : "false")
94
95 // Format 32-bit quantities.
96 #define INT32_FORMAT "%" PRId32
97 #define UINT32_FORMAT "%" PRIu32
98 #define INT32_FORMAT_W(width) "%" #width PRId32
99 #define UINT32_FORMAT_W(width) "%" #width PRIu32
100
101 #define PTR32_FORMAT "0x%08" PRIx32
102 #define PTR32_FORMAT_W(width) "0x%" #width PRIx32
103
104 // Format 64-bit quantities.
105 #define INT64_FORMAT "%" PRId64
106 #define UINT64_FORMAT "%" PRIu64
107 #define UINT64_FORMAT_X "%" PRIx64
108 #define INT64_FORMAT_W(width) "%" #width PRId64
109 #define UINT64_FORMAT_W(width) "%" #width PRIu64
110 #define UINT64_FORMAT_X_W(width) "%" #width PRIx64
111
112 #define PTR64_FORMAT "0x%016" PRIx64
113
114 // Format jlong, if necessary
115 #ifndef JLONG_FORMAT
116 #define JLONG_FORMAT INT64_FORMAT
117 #endif
118 #ifndef JLONG_FORMAT_W
119 #define JLONG_FORMAT_W(width) INT64_FORMAT_W(width)
120 #endif
121 #ifndef JULONG_FORMAT
122 #define JULONG_FORMAT UINT64_FORMAT
123 #endif
124 #ifndef JULONG_FORMAT_X
125 #define JULONG_FORMAT_X UINT64_FORMAT_X
126 #endif
127
128 // Format pointers which change size between 32- and 64-bit.
129 #ifdef _LP64
130 #define INTPTR_FORMAT "0x%016" PRIxPTR
131 #define PTR_FORMAT "0x%016" PRIxPTR
132 #else // !_LP64
133 #define INTPTR_FORMAT "0x%08" PRIxPTR
134 #define PTR_FORMAT "0x%08" PRIxPTR
135 #endif // _LP64
136
137 // Format pointers without leading zeros
138 #define INTPTRNZ_FORMAT "0x%" PRIxPTR
139
140 #define INTPTR_FORMAT_W(width) "%" #width PRIxPTR
141
142 #define SSIZE_FORMAT "%" PRIdPTR
143 #define SIZE_FORMAT "%" PRIuPTR
144 #define SIZE_FORMAT_HEX "0x%" PRIxPTR
145 #define SSIZE_FORMAT_W(width) "%" #width PRIdPTR
146 #define SIZE_FORMAT_W(width) "%" #width PRIuPTR
147 #define SIZE_FORMAT_HEX_W(width) "0x%" #width PRIxPTR
148
149 #define INTX_FORMAT "%" PRIdPTR
150 #define UINTX_FORMAT "%" PRIuPTR
151 #define INTX_FORMAT_W(width) "%" #width PRIdPTR
152 #define UINTX_FORMAT_W(width) "%" #width PRIuPTR
153
154 // Convert pointer to intptr_t, for use in printing pointers.
155 inline intptr_t p2i(const volatile void* p) {
156 return (intptr_t) p;
157 }
158
159 //----------------------------------------------------------------------------------------------------
160 // Constants
161
162 const int LogBytesPerShort = 1;
163 const int LogBytesPerInt = 2;
164 #ifdef _LP64
165 const int LogBytesPerWord = 3;
166 #else
167 const int LogBytesPerWord = 2;
168 #endif
169 const int LogBytesPerLong = 3;
170
171 const int BytesPerShort = 1 << LogBytesPerShort;
172 const int BytesPerInt = 1 << LogBytesPerInt;
173 const int BytesPerWord = 1 << LogBytesPerWord;
174 const int BytesPerLong = 1 << LogBytesPerLong;
175
176 const int LogBitsPerByte = 3;
177 const int LogBitsPerShort = LogBitsPerByte + LogBytesPerShort;
178 const int LogBitsPerInt = LogBitsPerByte + LogBytesPerInt;
179 const int LogBitsPerWord = LogBitsPerByte + LogBytesPerWord;
180 const int LogBitsPerLong = LogBitsPerByte + LogBytesPerLong;
181
182 const int BitsPerByte = 1 << LogBitsPerByte;
183 const int BitsPerShort = 1 << LogBitsPerShort;
184 const int BitsPerInt = 1 << LogBitsPerInt;
185 const int BitsPerWord = 1 << LogBitsPerWord;
186 const int BitsPerLong = 1 << LogBitsPerLong;
187
188 const int WordAlignmentMask = (1 << LogBytesPerWord) - 1;
189 const int LongAlignmentMask = (1 << LogBytesPerLong) - 1;
190
191 const int WordsPerLong = 2; // Number of stack entries for longs
192
193 const int oopSize = sizeof(char*); // Full-width oop
194 extern int heapOopSize; // Oop within a java object
195 const int wordSize = sizeof(char*);
196 const int longSize = sizeof(jlong);
197 const int jintSize = sizeof(jint);
198 const int size_tSize = sizeof(size_t);
199
200 const int BytesPerOop = BytesPerWord; // Full-width oop
201
202 extern int LogBytesPerHeapOop; // Oop within a java object
203 extern int LogBitsPerHeapOop;
204 extern int BytesPerHeapOop;
205 extern int BitsPerHeapOop;
206
207 const int BitsPerJavaInteger = 32;
208 const int BitsPerJavaLong = 64;
209 const int BitsPerSize_t = size_tSize * BitsPerByte;
210
211 // Size of a char[] needed to represent a jint as a string in decimal.
212 const int jintAsStringSize = 12;
213
214 // An opaque type, so that HeapWord* can be a generic pointer into the heap.
215 // We require that object sizes be measured in units of heap words (e.g.
216 // pointer-sized values), so that given HeapWord* hw,
217 // hw += oop(hw)->foo();
218 // works, where foo is a method (like size or scavenge) that returns the
219 // object size.
220 class HeapWordImpl; // Opaque, never defined.
221 typedef HeapWordImpl* HeapWord;
222
223 // Analogous opaque struct for metadata allocated from metaspaces.
224 class MetaWordImpl; // Opaque, never defined.
225 typedef MetaWordImpl* MetaWord;
226
227 // HeapWordSize must be 2^LogHeapWordSize.
228 const int HeapWordSize = sizeof(HeapWord);
229 #ifdef _LP64
230 const int LogHeapWordSize = 3;
231 #else
232 const int LogHeapWordSize = 2;
233 #endif
234 const int HeapWordsPerLong = BytesPerLong / HeapWordSize;
235 const int LogHeapWordsPerLong = LogBytesPerLong - LogHeapWordSize;
236
237 // The minimum number of native machine words necessary to contain "byte_size"
238 // bytes.
239 inline size_t heap_word_size(size_t byte_size) {
240 return (byte_size + (HeapWordSize-1)) >> LogHeapWordSize;
241 }
242
243 inline jfloat jfloat_cast(jint x);
244 inline jdouble jdouble_cast(jlong x);
245
246 //-------------------------------------------
247 // Constant for jlong (standardized by C++11)
248
249 // Build a 64bit integer constant
250 #define CONST64(x) (x ## LL)
251 #define UCONST64(x) (x ## ULL)
252
253 const jlong min_jlong = CONST64(0x8000000000000000);
254 const jlong max_jlong = CONST64(0x7fffffffffffffff);
255
256 //-------------------------------------------
257 // Constant for jdouble
258 const jlong min_jlongDouble = CONST64(0x0000000000000001);
259 const jdouble min_jdouble = jdouble_cast(min_jlongDouble);
260 const jlong max_jlongDouble = CONST64(0x7fefffffffffffff);
261 const jdouble max_jdouble = jdouble_cast(max_jlongDouble);
262
263 const size_t K = 1024;
264 const size_t M = K*K;
265 const size_t G = M*K;
266 const size_t HWperKB = K / sizeof(HeapWord);
267
268 // Constants for converting from a base unit to milli-base units. For
269 // example from seconds to milliseconds and microseconds
270
271 const int MILLIUNITS = 1000; // milli units per base unit
272 const int MICROUNITS = 1000000; // micro units per base unit
273 const int NANOUNITS = 1000000000; // nano units per base unit
274 const int NANOUNITS_PER_MILLIUNIT = NANOUNITS / MILLIUNITS;
275
276 const jlong NANOSECS_PER_SEC = CONST64(1000000000);
277 const jint NANOSECS_PER_MILLISEC = 1000000;
278
279
280 // Unit conversion functions
281 // The caller is responsible for considering overlow.
282
283 inline int64_t nanos_to_millis(int64_t nanos) {
284 return nanos / NANOUNITS_PER_MILLIUNIT;
285 }
286 inline int64_t millis_to_nanos(int64_t millis) {
287 return millis * NANOUNITS_PER_MILLIUNIT;
288 }
289
290 // Proper units routines try to maintain at least three significant digits.
291 // In worst case, it would print five significant digits with lower prefix.
292 // G is close to MAX_SIZE on 32-bit platforms, so its product can easily overflow,
293 // and therefore we need to be careful.
294
295 inline const char* proper_unit_for_byte_size(size_t s) {
296 #ifdef _LP64
297 if (s >= 100*G) {
298 return "G";
299 }
300 #endif
301 if (s >= 100*M) {
302 return "M";
303 } else if (s >= 100*K) {
304 return "K";
305 } else {
306 return "B";
307 }
308 }
309
310 template <class T>
311 inline T byte_size_in_proper_unit(T s) {
312 #ifdef _LP64
313 if (s >= 100*G) {
314 return (T)(s/G);
315 }
316 #endif
317 if (s >= 100*M) {
318 return (T)(s/M);
319 } else if (s >= 100*K) {
320 return (T)(s/K);
321 } else {
322 return s;
323 }
324 }
325
326 inline const char* exact_unit_for_byte_size(size_t s) {
327 #ifdef _LP64
328 if (s >= G && (s % G) == 0) {
329 return "G";
330 }
331 #endif
332 if (s >= M && (s % M) == 0) {
333 return "M";
334 }
335 if (s >= K && (s % K) == 0) {
336 return "K";
337 }
338 return "B";
339 }
340
341 inline size_t byte_size_in_exact_unit(size_t s) {
342 #ifdef _LP64
343 if (s >= G && (s % G) == 0) {
344 return s / G;
345 }
346 #endif
347 if (s >= M && (s % M) == 0) {
348 return s / M;
349 }
350 if (s >= K && (s % K) == 0) {
351 return s / K;
352 }
353 return s;
354 }
355
356 // Memory size transition formatting.
357
358 #define HEAP_CHANGE_FORMAT "%s: " SIZE_FORMAT "K(" SIZE_FORMAT "K)->" SIZE_FORMAT "K(" SIZE_FORMAT "K)"
359
360 #define HEAP_CHANGE_FORMAT_ARGS(_name_, _prev_used_, _prev_capacity_, _used_, _capacity_) \
361 (_name_), (_prev_used_) / K, (_prev_capacity_) / K, (_used_) / K, (_capacity_) / K
362
363 //----------------------------------------------------------------------------------------------------
364 // VM type definitions
365
366 // intx and uintx are the 'extended' int and 'extended' unsigned int types;
367 // they are 32bit wide on a 32-bit platform, and 64bit wide on a 64bit platform.
368
369 typedef intptr_t intx;
370 typedef uintptr_t uintx;
371
372 const intx min_intx = (intx)1 << (sizeof(intx)*BitsPerByte-1);
373 const intx max_intx = (uintx)min_intx - 1;
374 const uintx max_uintx = (uintx)-1;
375
376 // Table of values:
377 // sizeof intx 4 8
378 // min_intx 0x80000000 0x8000000000000000
379 // max_intx 0x7FFFFFFF 0x7FFFFFFFFFFFFFFF
380 // max_uintx 0xFFFFFFFF 0xFFFFFFFFFFFFFFFF
381
382 typedef unsigned int uint; NEEDS_CLEANUP
383
384
385 //----------------------------------------------------------------------------------------------------
386 // Java type definitions
387
388 // All kinds of 'plain' byte addresses
389 typedef signed char s_char;
390 typedef unsigned char u_char;
391 typedef u_char* address;
392 typedef uintptr_t address_word; // unsigned integer which will hold a pointer
393 // except for some implementations of a C++
394 // linkage pointer to function. Should never
395 // need one of those to be placed in this
396 // type anyway.
397
398 // Utility functions to "portably" (?) bit twiddle pointers
399 // Where portable means keep ANSI C++ compilers quiet
400
401 inline address set_address_bits(address x, int m) { return address(intptr_t(x) | m); }
402 inline address clear_address_bits(address x, int m) { return address(intptr_t(x) & ~m); }
403
404 // Utility functions to "portably" make cast to/from function pointers.
405
406 inline address_word mask_address_bits(address x, int m) { return address_word(x) & m; }
407 inline address_word castable_address(address x) { return address_word(x) ; }
408 inline address_word castable_address(void* x) { return address_word(x) ; }
409
410 // Pointer subtraction.
411 // The idea here is to avoid ptrdiff_t, which is signed and so doesn't have
412 // the range we might need to find differences from one end of the heap
413 // to the other.
414 // A typical use might be:
415 // if (pointer_delta(end(), top()) >= size) {
416 // // enough room for an object of size
417 // ...
418 // and then additions like
419 // ... top() + size ...
420 // are safe because we know that top() is at least size below end().
421 inline size_t pointer_delta(const volatile void* left,
422 const volatile void* right,
423 size_t element_size) {
424 assert(left >= right, "avoid underflow - left: " PTR_FORMAT " right: " PTR_FORMAT, p2i(left), p2i(right));
425 return (((uintptr_t) left) - ((uintptr_t) right)) / element_size;
426 }
427
428 // A version specialized for HeapWord*'s.
429 inline size_t pointer_delta(const HeapWord* left, const HeapWord* right) {
430 return pointer_delta(left, right, sizeof(HeapWord));
431 }
432 // A version specialized for MetaWord*'s.
433 inline size_t pointer_delta(const MetaWord* left, const MetaWord* right) {
434 return pointer_delta(left, right, sizeof(MetaWord));
435 }
436
437 //
438 // ANSI C++ does not allow casting from one pointer type to a function pointer
439 // directly without at best a warning. This macro accomplishes it silently
440 // In every case that is present at this point the value be cast is a pointer
441 // to a C linkage function. In some case the type used for the cast reflects
442 // that linkage and a picky compiler would not complain. In other cases because
443 // there is no convenient place to place a typedef with extern C linkage (i.e
444 // a platform dependent header file) it doesn't. At this point no compiler seems
445 // picky enough to catch these instances (which are few). It is possible that
446 // using templates could fix these for all cases. This use of templates is likely
447 // so far from the middle of the road that it is likely to be problematic in
448 // many C++ compilers.
449 //
450 #define CAST_TO_FN_PTR(func_type, value) (reinterpret_cast<func_type>(value))
451 #define CAST_FROM_FN_PTR(new_type, func_ptr) ((new_type)((address_word)(func_ptr)))
452
453 // In many places we've added C-style casts to silence compiler
454 // warnings, for example when truncating a size_t to an int when we
455 // know the size_t is a small struct. Such casts are risky because
456 // they effectively disable useful compiler warnings. We can make our
457 // lives safer with this function, which ensures that any cast is
458 // reversible without loss of information. It doesn't check
459 // everything: it isn't intended to make sure that pointer types are
460 // compatible, for example.
461 template <typename T2, typename T1>
462 T2 checked_cast(T1 thing) {
463 T2 result = static_cast<T2>(thing);
464 assert(static_cast<T1>(result) == thing, "must be");
465 return result;
466 }
467
468 // Need the correct linkage to call qsort without warnings
469 extern "C" {
470 typedef int (*_sort_Fn)(const void *, const void *);
471 }
472
473 // Unsigned byte types for os and stream.hpp
474
475 // Unsigned one, two, four and eigth byte quantities used for describing
476 // the .class file format. See JVM book chapter 4.
477
478 typedef jubyte u1;
479 typedef jushort u2;
480 typedef juint u4;
481 typedef julong u8;
482
483 const jubyte max_jubyte = (jubyte)-1; // 0xFF largest jubyte
484 const jushort max_jushort = (jushort)-1; // 0xFFFF largest jushort
485 const juint max_juint = (juint)-1; // 0xFFFFFFFF largest juint
486 const julong max_julong = (julong)-1; // 0xFF....FF largest julong
487
488 typedef jbyte s1;
489 typedef jshort s2;
490 typedef jint s4;
491 typedef jlong s8;
492
493 const jbyte min_jbyte = -(1 << 7); // smallest jbyte
494 const jbyte max_jbyte = (1 << 7) - 1; // largest jbyte
495 const jshort min_jshort = -(1 << 15); // smallest jshort
496 const jshort max_jshort = (1 << 15) - 1; // largest jshort
497
498 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
499 const jint max_jint = (juint)min_jint - 1; // 0x7FFFFFFF == largest jint
500
501 const jint min_jintFloat = (jint)(0x00000001);
502 const jfloat min_jfloat = jfloat_cast(min_jintFloat);
503 const jint max_jintFloat = (jint)(0x7f7fffff);
504 const jfloat max_jfloat = jfloat_cast(max_jintFloat);
505
506 //----------------------------------------------------------------------------------------------------
507 // JVM spec restrictions
508
509 const int max_method_code_size = 64*K - 1; // JVM spec, 2nd ed. section 4.8.1 (p.134)
510
511 //----------------------------------------------------------------------------------------------------
512 // Object alignment, in units of HeapWords.
513 //
514 // Minimum is max(BytesPerLong, BytesPerDouble, BytesPerOop) / HeapWordSize, so jlong, jdouble and
515 // reference fields can be naturally aligned.
516
517 extern int MinObjAlignment;
518 extern int MinObjAlignmentInBytes;
519 extern int MinObjAlignmentInBytesMask;
520
521 extern int LogMinObjAlignment;
522 extern int LogMinObjAlignmentInBytes;
523
524 const int LogKlassAlignmentInBytes = 3;
525 const int LogKlassAlignment = LogKlassAlignmentInBytes - LogHeapWordSize;
526 const int KlassAlignmentInBytes = 1 << LogKlassAlignmentInBytes;
527 const int KlassAlignment = KlassAlignmentInBytes / HeapWordSize;
528
529 // Maximal size of heap where unscaled compression can be used. Also upper bound
530 // for heap placement: 4GB.
531 const uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
532 // Maximal size of heap where compressed oops can be used. Also upper bound for heap
533 // placement for zero based compression algorithm: UnscaledOopHeapMax << LogMinObjAlignmentInBytes.
534 extern uint64_t OopEncodingHeapMax;
535
536 // Maximal size of compressed class space. Above this limit compression is not possible.
537 // Also upper bound for placement of zero based class space. (Class space is further limited
538 // to be < 3G, see arguments.cpp.)
539 const uint64_t KlassEncodingMetaspaceMax = (uint64_t(max_juint) + 1) << LogKlassAlignmentInBytes;
540
541 // Machine dependent stuff
542
543 // The maximum size of the code cache. Can be overridden by targets.
544 #define CODE_CACHE_SIZE_LIMIT (2*G)
545 // Allow targets to reduce the default size of the code cache.
546 #define CODE_CACHE_DEFAULT_LIMIT CODE_CACHE_SIZE_LIMIT
547
548 #include CPU_HEADER(globalDefinitions)
549
550 // To assure the IRIW property on processors that are not multiple copy
551 // atomic, sync instructions must be issued between volatile reads to
552 // assure their ordering, instead of after volatile stores.
553 // (See "A Tutorial Introduction to the ARM and POWER Relaxed Memory Models"
554 // by Luc Maranget, Susmit Sarkar and Peter Sewell, INRIA/Cambridge)
555 #ifdef CPU_MULTI_COPY_ATOMIC
556 // Not needed.
557 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = false;
558 #else
559 // From all non-multi-copy-atomic architectures, only PPC64 supports IRIW at the moment.
560 // Final decision is subject to JEP 188: Java Memory Model Update.
561 const bool support_IRIW_for_not_multiple_copy_atomic_cpu = PPC64_ONLY(true) NOT_PPC64(false);
562 #endif
563
564 // The expected size in bytes of a cache line, used to pad data structures.
565 #ifndef DEFAULT_CACHE_LINE_SIZE
566 #define DEFAULT_CACHE_LINE_SIZE 64
567 #endif
568
569
570 //----------------------------------------------------------------------------------------------------
571 // Utility macros for compilers
572 // used to silence compiler warnings
573
574 #define Unused_Variable(var) var
575
576
577 //----------------------------------------------------------------------------------------------------
578 // Prototyping
579 // "Code Missing Here" macro, un-define when integrating back from prototyping stage and break
580 // compilation on purpose (i.e. "forget me not")
581 #define PROTOTYPE
582 #ifdef PROTOTYPE
583 #define CMH(m)
584 #endif
585
586 //----------------------------------------------------------------------------------------------------
587 // Miscellaneous
588
589 // 6302670 Eliminate Hotspot __fabsf dependency
590 // All fabs() callers should call this function instead, which will implicitly
591 // convert the operand to double, avoiding a dependency on __fabsf which
592 // doesn't exist in early versions of Solaris 8.
593 inline double fabsd(double value) {
594 return fabs(value);
595 }
596
597 // Returns numerator/denominator as percentage value from 0 to 100. If denominator
598 // is zero, return 0.0.
599 template<typename T>
600 inline double percent_of(T numerator, T denominator) {
601 return denominator != 0 ? (double)numerator / denominator * 100.0 : 0.0;
602 }
603
604 //----------------------------------------------------------------------------------------------------
605 // Special casts
606 // Cast floats into same-size integers and vice-versa w/o changing bit-pattern
607 typedef union {
608 jfloat f;
609 jint i;
610 } FloatIntConv;
611
612 typedef union {
613 jdouble d;
614 jlong l;
615 julong ul;
616 } DoubleLongConv;
617
618 inline jint jint_cast (jfloat x) { return ((FloatIntConv*)&x)->i; }
619 inline jfloat jfloat_cast (jint x) { return ((FloatIntConv*)&x)->f; }
620
621 inline jlong jlong_cast (jdouble x) { return ((DoubleLongConv*)&x)->l; }
622 inline julong julong_cast (jdouble x) { return ((DoubleLongConv*)&x)->ul; }
623 inline jdouble jdouble_cast (jlong x) { return ((DoubleLongConv*)&x)->d; }
624
625 inline jint low (jlong value) { return jint(value); }
626 inline jint high(jlong value) { return jint(value >> 32); }
627
628 // the fancy casts are a hopefully portable way
629 // to do unsigned 32 to 64 bit type conversion
630 inline void set_low (jlong* value, jint low ) { *value &= (jlong)0xffffffff << 32;
631 *value |= (jlong)(julong)(juint)low; }
632
633 inline void set_high(jlong* value, jint high) { *value &= (jlong)(julong)(juint)0xffffffff;
634 *value |= (jlong)high << 32; }
635
636 inline jlong jlong_from(jint h, jint l) {
637 jlong result = 0; // initialization to avoid warning
638 set_high(&result, h);
639 set_low(&result, l);
640 return result;
641 }
642
643 union jlong_accessor {
644 jint words[2];
645 jlong long_value;
646 };
647
648 void basic_types_init(); // cannot define here; uses assert
649
650
651 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
652 enum BasicType {
653 // The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS.
654 T_BOOLEAN = JVM_T_BOOLEAN,
655 T_CHAR = JVM_T_CHAR,
656 T_FLOAT = JVM_T_FLOAT,
657 T_DOUBLE = JVM_T_DOUBLE,
658 T_BYTE = JVM_T_BYTE,
659 T_SHORT = JVM_T_SHORT,
660 T_INT = JVM_T_INT,
661 T_LONG = JVM_T_LONG,
662 // The remaining values are not part of any standard.
663 // T_OBJECT and T_VOID denote two more semantic choices
664 // for method return values.
665 // T_OBJECT and T_ARRAY describe signature syntax.
666 // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe
667 // internal references within the JVM as if they were Java
668 // types in their own right.
669 T_OBJECT = 12,
670 T_ARRAY = 13,
671 T_INLINE_TYPE = 14,
672 T_VOID = 15,
673 T_ADDRESS = 16,
674 T_NARROWOOP = 17,
675 T_METADATA = 18,
676 T_NARROWKLASS = 19,
677 T_CONFLICT = 20, // for stack value type with conflicting contents
678 T_ILLEGAL = 99
679 };
680
681 #define SIGNATURE_TYPES_DO(F, N) \
682 F(JVM_SIGNATURE_BOOLEAN, T_BOOLEAN, N) \
683 F(JVM_SIGNATURE_CHAR, T_CHAR, N) \
684 F(JVM_SIGNATURE_FLOAT, T_FLOAT, N) \
685 F(JVM_SIGNATURE_DOUBLE, T_DOUBLE, N) \
686 F(JVM_SIGNATURE_BYTE, T_BYTE, N) \
687 F(JVM_SIGNATURE_SHORT, T_SHORT, N) \
688 F(JVM_SIGNATURE_INT, T_INT, N) \
689 F(JVM_SIGNATURE_LONG, T_LONG, N) \
690 F(JVM_SIGNATURE_CLASS, T_OBJECT, N) \
691 F(JVM_SIGNATURE_ARRAY, T_ARRAY, N) \
692 F(JVM_SIGNATURE_INLINE_TYPE, T_INLINE_TYPE, N) \
693 F(JVM_SIGNATURE_VOID, T_VOID, N) \
694 /*end*/
695
696 inline bool is_java_type(BasicType t) {
697 return T_BOOLEAN <= t && t <= T_VOID;
698 }
699
700 inline bool is_java_primitive(BasicType t) {
701 return T_BOOLEAN <= t && t <= T_LONG;
702 }
703
704 inline bool is_subword_type(BasicType t) {
705 // these guys are processed exactly like T_INT in calling sequences:
706 return (t == T_BOOLEAN || t == T_CHAR || t == T_BYTE || t == T_SHORT);
707 }
708
709 inline bool is_signed_subword_type(BasicType t) {
710 return (t == T_BYTE || t == T_SHORT);
711 }
712
713 inline bool is_double_word_type(BasicType t) {
714 return (t == T_DOUBLE || t == T_LONG);
715 }
716
717 inline bool is_reference_type(BasicType t) {
718 return (t == T_OBJECT || t == T_ARRAY || t == T_INLINE_TYPE);
719 }
720
721 inline bool is_integral_type(BasicType t) {
722 return is_subword_type(t) || t == T_INT || t == T_LONG;
723 }
724
725 inline bool is_floating_point_type(BasicType t) {
726 return (t == T_FLOAT || t == T_DOUBLE);
727 }
728
729 extern char type2char_tab[T_CONFLICT+1]; // Map a BasicType to a jchar
730 inline char type2char(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2char_tab[t] : 0; }
731 extern int type2size[T_CONFLICT+1]; // Map BasicType to result stack elements
732 extern const char* type2name_tab[T_CONFLICT+1]; // Map a BasicType to a jchar
733 inline const char* type2name(BasicType t) { return (uint)t < T_CONFLICT+1 ? type2name_tab[t] : NULL; }
734 extern BasicType name2type(const char* name);
735
736 inline jlong max_signed_integer(BasicType bt) {
737 if (bt == T_INT) {
738 return max_jint;
739 }
740 assert(bt == T_LONG, "unsupported");
741 return max_jlong;
742 }
743
744 inline jlong min_signed_integer(BasicType bt) {
745 if (bt == T_INT) {
746 return min_jint;
747 }
748 assert(bt == T_LONG, "unsupported");
749 return min_jlong;
750 }
751
752 // Auxiliary math routines
753 // least common multiple
754 extern size_t lcm(size_t a, size_t b);
755
756
757 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
758 enum BasicTypeSize {
759 T_BOOLEAN_size = 1,
760 T_CHAR_size = 1,
761 T_FLOAT_size = 1,
762 T_DOUBLE_size = 2,
763 T_BYTE_size = 1,
764 T_SHORT_size = 1,
765 T_INT_size = 1,
766 T_LONG_size = 2,
767 T_OBJECT_size = 1,
768 T_ARRAY_size = 1,
769 T_NARROWOOP_size = 1,
770 T_NARROWKLASS_size = 1,
771 T_VOID_size = 0,
772 T_INLINE_TYPE_size = 1
773 };
774
775 // this works on valid parameter types but not T_VOID, T_CONFLICT, etc.
776 inline int parameter_type_word_count(BasicType t) {
777 if (is_double_word_type(t)) return 2;
778 assert(is_java_primitive(t) || is_reference_type(t), "no goofy types here please");
779 assert(type2size[t] == 1, "must be");
780 return 1;
781 }
782
783 // maps a BasicType to its instance field storage type:
784 // all sub-word integral types are widened to T_INT
785 extern BasicType type2field[T_CONFLICT+1];
786 extern BasicType type2wfield[T_CONFLICT+1];
787
788
789 // size in bytes
790 enum ArrayElementSize {
791 T_BOOLEAN_aelem_bytes = 1,
792 T_CHAR_aelem_bytes = 2,
793 T_FLOAT_aelem_bytes = 4,
794 T_DOUBLE_aelem_bytes = 8,
795 T_BYTE_aelem_bytes = 1,
796 T_SHORT_aelem_bytes = 2,
797 T_INT_aelem_bytes = 4,
798 T_LONG_aelem_bytes = 8,
799 #ifdef _LP64
800 T_OBJECT_aelem_bytes = 8,
801 T_ARRAY_aelem_bytes = 8,
802 T_INLINE_TYPE_aelem_bytes = 8,
803 #else
804 T_OBJECT_aelem_bytes = 4,
805 T_ARRAY_aelem_bytes = 4,
806 T_INLINE_TYPE_aelem_bytes = 4,
807 #endif
808 T_NARROWOOP_aelem_bytes = 4,
809 T_NARROWKLASS_aelem_bytes = 4,
810 T_VOID_aelem_bytes = 0
811 };
812
813 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element
814 #ifdef ASSERT
815 extern int type2aelembytes(BasicType t, bool allow_address = false); // asserts
816 #else
817 inline int type2aelembytes(BasicType t, bool allow_address = false) { return _type2aelembytes[t]; }
818 #endif
819
820
821 // JavaValue serves as a container for arbitrary Java values.
822
823 class JavaValue {
824
825 public:
826 typedef union JavaCallValue {
827 jfloat f;
828 jdouble d;
829 jint i;
830 jlong l;
831 jobject h;
832 oopDesc* o;
833 } JavaCallValue;
834
835 private:
836 BasicType _type;
837 JavaCallValue _value;
838
839 public:
840 JavaValue(BasicType t = T_ILLEGAL) { _type = t; }
841
842 JavaValue(jfloat value) {
843 _type = T_FLOAT;
844 _value.f = value;
845 }
846
847 JavaValue(jdouble value) {
848 _type = T_DOUBLE;
849 _value.d = value;
850 }
851
852 jfloat get_jfloat() const { return _value.f; }
853 jdouble get_jdouble() const { return _value.d; }
854 jint get_jint() const { return _value.i; }
855 jlong get_jlong() const { return _value.l; }
856 jobject get_jobject() const { return _value.h; }
857 oopDesc* get_oop() const { return _value.o; }
858 JavaCallValue* get_value_addr() { return &_value; }
859 BasicType get_type() const { return _type; }
860
861 void set_jfloat(jfloat f) { _value.f = f;}
862 void set_jdouble(jdouble d) { _value.d = d;}
863 void set_jint(jint i) { _value.i = i;}
864 void set_jlong(jlong l) { _value.l = l;}
865 void set_jobject(jobject h) { _value.h = h;}
866 void set_oop(oopDesc* o) { _value.o = o;}
867 void set_type(BasicType t) { _type = t; }
868
869 jboolean get_jboolean() const { return (jboolean) (_value.i);}
870 jbyte get_jbyte() const { return (jbyte) (_value.i);}
871 jchar get_jchar() const { return (jchar) (_value.i);}
872 jshort get_jshort() const { return (jshort) (_value.i);}
873
874 };
875
876
877 // TosState describes the top-of-stack state before and after the execution of
878 // a bytecode or method. The top-of-stack value may be cached in one or more CPU
879 // registers. The TosState corresponds to the 'machine representation' of this cached
880 // value. There's 4 states corresponding to the JAVA types int, long, float & double
881 // as well as a 5th state in case the top-of-stack value is actually on the top
882 // of stack (in memory) and thus not cached. The atos state corresponds to the itos
883 // state when it comes to machine representation but is used separately for (oop)
884 // type specific operations (e.g. verification code).
885
886 enum TosState { // describes the tos cache contents
887 btos = 0, // byte, bool tos cached
888 ztos = 1, // byte, bool tos cached
889 ctos = 2, // char tos cached
890 stos = 3, // short tos cached
891 itos = 4, // int tos cached
892 ltos = 5, // long tos cached
893 ftos = 6, // float tos cached
894 dtos = 7, // double tos cached
895 atos = 8, // object cached
896 vtos = 9, // tos not cached,
897 number_of_states,
898 ilgl // illegal state: should not occur
899 };
900
901
902 inline TosState as_TosState(BasicType type) {
903 switch (type) {
904 case T_BYTE : return btos;
905 case T_BOOLEAN: return ztos;
906 case T_CHAR : return ctos;
907 case T_SHORT : return stos;
908 case T_INT : return itos;
909 case T_LONG : return ltos;
910 case T_FLOAT : return ftos;
911 case T_DOUBLE : return dtos;
912 case T_VOID : return vtos;
913 case T_INLINE_TYPE: // fall through
914 case T_ARRAY : // fall through
915 case T_OBJECT : return atos;
916 default : return ilgl;
917 }
918 }
919
920 inline BasicType as_BasicType(TosState state) {
921 switch (state) {
922 case btos : return T_BYTE;
923 case ztos : return T_BOOLEAN;
924 case ctos : return T_CHAR;
925 case stos : return T_SHORT;
926 case itos : return T_INT;
927 case ltos : return T_LONG;
928 case ftos : return T_FLOAT;
929 case dtos : return T_DOUBLE;
930 case atos : return T_OBJECT;
931 case vtos : return T_VOID;
932 default : return T_ILLEGAL;
933 }
934 }
935
936
937 // Helper function to convert BasicType info into TosState
938 // Note: Cannot define here as it uses global constant at the time being.
939 TosState as_TosState(BasicType type);
940
941
942 // JavaThreadState keeps track of which part of the code a thread is executing in. This
943 // information is needed by the safepoint code.
944 //
945 // There are 4 essential states:
946 //
947 // _thread_new : Just started, but not executed init. code yet (most likely still in OS init code)
948 // _thread_in_native : In native code. This is a safepoint region, since all oops will be in jobject handles
949 // _thread_in_vm : Executing in the vm
950 // _thread_in_Java : Executing either interpreted or compiled Java code (or could be in a stub)
951 //
952 // Each state has an associated xxxx_trans state, which is an intermediate state used when a thread is in
953 // a transition from one state to another. These extra states makes it possible for the safepoint code to
954 // handle certain thread_states without having to suspend the thread - making the safepoint code faster.
955 //
956 // Given a state, the xxxx_trans state can always be found by adding 1.
957 //
958 enum JavaThreadState {
959 _thread_uninitialized = 0, // should never happen (missing initialization)
960 _thread_new = 2, // just starting up, i.e., in process of being initialized
961 _thread_new_trans = 3, // corresponding transition state (not used, included for completness)
962 _thread_in_native = 4, // running in native code
963 _thread_in_native_trans = 5, // corresponding transition state
964 _thread_in_vm = 6, // running in VM
965 _thread_in_vm_trans = 7, // corresponding transition state
966 _thread_in_Java = 8, // running in Java or in stub code
967 _thread_in_Java_trans = 9, // corresponding transition state (not used, included for completness)
968 _thread_blocked = 10, // blocked in vm
969 _thread_blocked_trans = 11, // corresponding transition state
970 _thread_max_state = 12 // maximum thread state+1 - used for statistics allocation
971 };
972
973 //----------------------------------------------------------------------------------------------------
974 // Special constants for debugging
975
976 const jint badInt = -3; // generic "bad int" value
977 const intptr_t badAddressVal = -2; // generic "bad address" value
978 const intptr_t badOopVal = -1; // generic "bad oop" value
979 const intptr_t badHeapOopVal = (intptr_t) CONST64(0x2BAD4B0BBAADBABE); // value used to zap heap after GC
980 const int badStackSegVal = 0xCA; // value used to zap stack segments
981 const int badHandleValue = 0xBC; // value used to zap vm handle area
982 const int badResourceValue = 0xAB; // value used to zap resource area
983 const int freeBlockPad = 0xBA; // value used to pad freed blocks.
984 const int uninitBlockPad = 0xF1; // value used to zap newly malloc'd blocks.
985 const juint uninitMetaWordVal= 0xf7f7f7f7; // value used to zap newly allocated metachunk
986 const juint badHeapWordVal = 0xBAADBABE; // value used to zap heap after GC
987 const juint badMetaWordVal = 0xBAADFADE; // value used to zap metadata heap after GC
988 const int badCodeHeapNewVal= 0xCC; // value used to zap Code heap at allocation
989 const int badCodeHeapFreeVal = 0xDD; // value used to zap Code heap at deallocation
990
991
992 // (These must be implemented as #defines because C++ compilers are
993 // not obligated to inline non-integral constants!)
994 #define badAddress ((address)::badAddressVal)
995 #define badOop (cast_to_oop(::badOopVal))
996 #define badHeapWord (::badHeapWordVal)
997
998 // Default TaskQueue size is 16K (32-bit) or 128K (64-bit)
999 #define TASKQUEUE_SIZE (NOT_LP64(1<<14) LP64_ONLY(1<<17))
1000
1001 //----------------------------------------------------------------------------------------------------
1002 // Utility functions for bitfield manipulations
1003
1004 const intptr_t AllBits = ~0; // all bits set in a word
1005 const intptr_t NoBits = 0; // no bits set in a word
1006 const jlong NoLongBits = 0; // no bits set in a long
1007 const intptr_t OneBit = 1; // only right_most bit set in a word
1008
1009 // get a word with the n.th or the right-most or left-most n bits set
1010 // (note: #define used only so that they can be used in enum constant definitions)
1011 #define nth_bit(n) (((n) >= BitsPerWord) ? 0 : (OneBit << (n)))
1012 #define right_n_bits(n) (nth_bit(n) - 1)
1013
1014 // bit-operations using a mask m
1015 inline void set_bits (intptr_t& x, intptr_t m) { x |= m; }
1016 inline void clear_bits (intptr_t& x, intptr_t m) { x &= ~m; }
1017 inline intptr_t mask_bits (intptr_t x, intptr_t m) { return x & m; }
1018 inline jlong mask_long_bits (jlong x, jlong m) { return x & m; }
1019 inline bool mask_bits_are_true (intptr_t flags, intptr_t mask) { return (flags & mask) == mask; }
1020
1021 // bit-operations using the n.th bit
1022 inline void set_nth_bit(intptr_t& x, int n) { set_bits (x, nth_bit(n)); }
1023 inline void clear_nth_bit(intptr_t& x, int n) { clear_bits(x, nth_bit(n)); }
1024 inline bool is_set_nth_bit(intptr_t x, int n) { return mask_bits (x, nth_bit(n)) != NoBits; }
1025
1026 // returns the bitfield of x starting at start_bit_no with length field_length (no sign-extension!)
1027 inline intptr_t bitfield(intptr_t x, int start_bit_no, int field_length) {
1028 return mask_bits(x >> start_bit_no, right_n_bits(field_length));
1029 }
1030
1031
1032 //----------------------------------------------------------------------------------------------------
1033 // Utility functions for integers
1034
1035 // Avoid use of global min/max macros which may cause unwanted double
1036 // evaluation of arguments.
1037 #ifdef max
1038 #undef max
1039 #endif
1040
1041 #ifdef min
1042 #undef min
1043 #endif
1044
1045 // It is necessary to use templates here. Having normal overloaded
1046 // functions does not work because it is necessary to provide both 32-
1047 // and 64-bit overloaded functions, which does not work, and having
1048 // explicitly-typed versions of these routines (i.e., MAX2I, MAX2L)
1049 // will be even more error-prone than macros.
1050 template<class T> constexpr T MAX2(T a, T b) { return (a > b) ? a : b; }
1051 template<class T> constexpr T MIN2(T a, T b) { return (a < b) ? a : b; }
1052 template<class T> constexpr T MAX3(T a, T b, T c) { return MAX2(MAX2(a, b), c); }
1053 template<class T> constexpr T MIN3(T a, T b, T c) { return MIN2(MIN2(a, b), c); }
1054 template<class T> constexpr T MAX4(T a, T b, T c, T d) { return MAX2(MAX3(a, b, c), d); }
1055 template<class T> constexpr T MIN4(T a, T b, T c, T d) { return MIN2(MIN3(a, b, c), d); }
1056
1057 template<class T> inline T ABS(T x) { return (x > 0) ? x : -x; }
1058
1059 // Return the given value clamped to the range [min ... max]
1060 template<typename T>
1061 inline T clamp(T value, T min, T max) {
1062 assert(min <= max, "must be");
1063 return MIN2(MAX2(value, min), max);
1064 }
1065
1066 inline bool is_odd (intx x) { return x & 1; }
1067 inline bool is_even(intx x) { return !is_odd(x); }
1068
1069 // abs methods which cannot overflow and so are well-defined across
1070 // the entire domain of integer types.
1071 static inline unsigned int uabs(unsigned int n) {
1072 union {
1073 unsigned int result;
1074 int value;
1075 };
1076 result = n;
1077 if (value < 0) result = 0-result;
1078 return result;
1079 }
1080 static inline julong uabs(julong n) {
1081 union {
1082 julong result;
1083 jlong value;
1084 };
1085 result = n;
1086 if (value < 0) result = 0-result;
1087 return result;
1088 }
1089 static inline julong uabs(jlong n) { return uabs((julong)n); }
1090 static inline unsigned int uabs(int n) { return uabs((unsigned int)n); }
1091
1092 // "to" should be greater than "from."
1093 inline intx byte_size(void* from, void* to) {
1094 return (address)to - (address)from;
1095 }
1096
1097
1098 // Pack and extract shorts to/from ints:
1099
1100 inline int extract_low_short_from_int(jint x) {
1101 return x & 0xffff;
1102 }
1103
1104 inline int extract_high_short_from_int(jint x) {
1105 return (x >> 16) & 0xffff;
1106 }
1107
1108 inline int build_int_from_shorts( jushort low, jushort high ) {
1109 return ((int)((unsigned int)high << 16) | (unsigned int)low);
1110 }
1111
1112 // swap a & b
1113 template<class T> static void swap(T& a, T& b) {
1114 T tmp = a;
1115 a = b;
1116 b = tmp;
1117 }
1118
1119 // array_size_impl is a function that takes a reference to T[N] and
1120 // returns a reference to char[N]. It is not ODR-used, so not defined.
1121 template<typename T, size_t N> char (&array_size_impl(T (&)[N]))[N];
1122
1123 #define ARRAY_SIZE(array) sizeof(array_size_impl(array))
1124
1125 //----------------------------------------------------------------------------------------------------
1126 // Sum and product which can never overflow: they wrap, just like the
1127 // Java operations. Note that we don't intend these to be used for
1128 // general-purpose arithmetic: their purpose is to emulate Java
1129 // operations.
1130
1131 // The goal of this code to avoid undefined or implementation-defined
1132 // behavior. The use of an lvalue to reference cast is explicitly
1133 // permitted by Lvalues and rvalues [basic.lval]. [Section 3.10 Para
1134 // 15 in C++03]
1135 #define JAVA_INTEGER_OP(OP, NAME, TYPE, UNSIGNED_TYPE) \
1136 inline TYPE NAME (TYPE in1, TYPE in2) { \
1137 UNSIGNED_TYPE ures = static_cast<UNSIGNED_TYPE>(in1); \
1138 ures OP ## = static_cast<UNSIGNED_TYPE>(in2); \
1139 return reinterpret_cast<TYPE&>(ures); \
1140 }
1141
1142 JAVA_INTEGER_OP(+, java_add, jint, juint)
1143 JAVA_INTEGER_OP(-, java_subtract, jint, juint)
1144 JAVA_INTEGER_OP(*, java_multiply, jint, juint)
1145 JAVA_INTEGER_OP(+, java_add, jlong, julong)
1146 JAVA_INTEGER_OP(-, java_subtract, jlong, julong)
1147 JAVA_INTEGER_OP(*, java_multiply, jlong, julong)
1148
1149 #undef JAVA_INTEGER_OP
1150
1151 // Provide integer shift operations with Java semantics. No overflow
1152 // issues - left shifts simply discard shifted out bits. No undefined
1153 // behavior for large or negative shift quantities; instead the actual
1154 // shift distance is the argument modulo the lhs value's size in bits.
1155 // No undefined or implementation defined behavior for shifting negative
1156 // values; left shift discards bits, right shift sign extends. We use
1157 // the same safe conversion technique as above for java_add and friends.
1158 #define JAVA_INTEGER_SHIFT_OP(OP, NAME, TYPE, XTYPE) \
1159 inline TYPE NAME (TYPE lhs, jint rhs) { \
1160 const uint rhs_mask = (sizeof(TYPE) * 8) - 1; \
1161 STATIC_ASSERT(rhs_mask == 31 || rhs_mask == 63); \
1162 XTYPE xres = static_cast<XTYPE>(lhs); \
1163 xres OP ## = (rhs & rhs_mask); \
1164 return reinterpret_cast<TYPE&>(xres); \
1165 }
1166
1167 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jint, juint)
1168 JAVA_INTEGER_SHIFT_OP(<<, java_shift_left, jlong, julong)
1169 // For signed shift right, assume C++ implementation >> sign extends.
1170 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jint, jint)
1171 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right, jlong, jlong)
1172 // For >>> use C++ unsigned >>.
1173 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jint, juint)
1174 JAVA_INTEGER_SHIFT_OP(>>, java_shift_right_unsigned, jlong, julong)
1175
1176 #undef JAVA_INTEGER_SHIFT_OP
1177
1178 //----------------------------------------------------------------------------------------------------
1179 // The goal of this code is to provide saturating operations for int/uint.
1180 // Checks overflow conditions and saturates the result to min_jint/max_jint.
1181 #define SATURATED_INTEGER_OP(OP, NAME, TYPE1, TYPE2) \
1182 inline int NAME (TYPE1 in1, TYPE2 in2) { \
1183 jlong res = static_cast<jlong>(in1); \
1184 res OP ## = static_cast<jlong>(in2); \
1185 if (res > max_jint) { \
1186 res = max_jint; \
1187 } else if (res < min_jint) { \
1188 res = min_jint; \
1189 } \
1190 return static_cast<int>(res); \
1191 }
1192
1193 SATURATED_INTEGER_OP(+, saturated_add, int, int)
1194 SATURATED_INTEGER_OP(+, saturated_add, int, uint)
1195 SATURATED_INTEGER_OP(+, saturated_add, uint, int)
1196 SATURATED_INTEGER_OP(+, saturated_add, uint, uint)
1197
1198 #undef SATURATED_INTEGER_OP
1199
1200 // Dereference vptr
1201 // All C++ compilers that we know of have the vtbl pointer in the first
1202 // word. If there are exceptions, this function needs to be made compiler
1203 // specific.
1204 static inline void* dereference_vptr(const void* addr) {
1205 return *(void**)addr;
1206 }
1207
1208 //----------------------------------------------------------------------------------------------------
1209 // String type aliases used by command line flag declarations and
1210 // processing utilities.
1211
1212 typedef const char* ccstr;
1213 typedef const char* ccstrlist; // represents string arguments which accumulate
1214
1215 //----------------------------------------------------------------------------------------------------
1216 // Default hash/equals functions used by ResourceHashtable
1217
1218 template<typename K> unsigned primitive_hash(const K& k) {
1219 unsigned hash = (unsigned)((uintptr_t)k);
1220 return hash ^ (hash >> 3); // just in case we're dealing with aligned ptrs
1221 }
1222
1223 template<typename K> bool primitive_equals(const K& k0, const K& k1) {
1224 return k0 == k1;
1225 }
1226
1227 // TEMP!!!!
1228 // This should be removed after LW2 arrays are implemented (JDK-8220790).
1229 // It's an alias to (EnableValhalla && (FlatArrayElementMaxSize != 0)),
1230 // which is actually not 100% correct, but works for the current set of C1/C2
1231 // implementation and test cases.
1232 #define UseFlatArray (EnableValhalla && (FlatArrayElementMaxSize != 0))
1233
1234 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP