1 /*
  2  * Copyright (c) 1997, 2024, 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_RUNTIME_STUBROUTINES_HPP
 26 #define SHARE_RUNTIME_STUBROUTINES_HPP
 27 
 28 #include "code/codeBlob.hpp"
 29 #include "memory/allocation.hpp"
 30 #include "prims/vectorSupport.hpp"
 31 #include "runtime/frame.hpp"
 32 #include "runtime/mutexLocker.hpp"
 33 #include "runtime/stubCodeGenerator.hpp"
 34 #include "runtime/threadWXSetters.inline.hpp"
 35 #include "utilities/macros.hpp"
 36 
 37 // StubRoutines provides entry points to assembly routines used by
 38 // compiled code and the run-time system. Platform-specific entry
 39 // points are defined in the platform-specific inner class.
 40 //
 41 // Class scheme:
 42 //
 43 //    platform-independent               platform-dependent
 44 //
 45 //    stubRoutines.hpp  <-- included --  stubRoutines_<arch>.hpp
 46 //           ^                                  ^
 47 //           |                                  |
 48 //       implements                         implements
 49 //           |                                  |
 50 //           |                                  |
 51 //    stubRoutines.cpp                   stubRoutines_<arch>.cpp
 52 //    stubRoutines_<os_family>.cpp       stubGenerator_<arch>.cpp
 53 //    stubRoutines_<os_arch>.cpp
 54 //
 55 // Note 1: The important thing is a clean decoupling between stub
 56 //         entry points (interfacing to the whole vm; i.e., 1-to-n
 57 //         relationship) and stub generators (interfacing only to
 58 //         the entry points implementation; i.e., 1-to-1 relationship).
 59 //         This significantly simplifies changes in the generator
 60 //         structure since the rest of the vm is not affected.
 61 //
 62 // Note 2: stubGenerator_<arch>.cpp contains a minimal portion of
 63 //         machine-independent code; namely the generator calls of
 64 //         the generator functions that are used platform-independently.
 65 //         However, it comes with the advantage of having a 1-file
 66 //         implementation of the generator. It should be fairly easy
 67 //         to change, should it become a problem later.
 68 //
 69 // Scheme for adding a new entry point:
 70 //
 71 // 1. determine if it's a platform-dependent or independent entry point
 72 //    a) if platform independent: make subsequent changes in the independent files
 73 //    b) if platform   dependent: make subsequent changes in the   dependent files
 74 // 2. add a private instance variable holding the entry point address
 75 // 3. add a public accessor function to the instance variable
 76 // 4. implement the corresponding generator function in the platform-dependent
 77 //    stubGenerator_<arch>.cpp file and call the function in generate_all() of that file
 78 
 79 class UnsafeMemoryAccess : public CHeapObj<mtCode> {
 80  private:
 81   address _start_pc;
 82   address _end_pc;
 83   address _error_exit_pc;
 84  public:
 85   static address           _common_exit_stub_pc;
 86   static UnsafeMemoryAccess* _table;
 87   static int               _table_length;
 88   static int               _table_max_length;
 89   UnsafeMemoryAccess() : _start_pc(nullptr), _end_pc(nullptr), _error_exit_pc(nullptr) {}
 90   void    set_start_pc(address pc)      { _start_pc = pc; }
 91   void    set_end_pc(address pc)        { _end_pc = pc; }
 92   void    set_error_exit_pc(address pc) { _error_exit_pc = pc; }
 93   address start_pc()      const { return _start_pc; }
 94   address end_pc()        const { return _end_pc; }
 95   address error_exit_pc() const { return _error_exit_pc; }
 96 
 97   static void    set_common_exit_stub_pc(address pc) { _common_exit_stub_pc = pc; }
 98   static address common_exit_stub_pc()               { return _common_exit_stub_pc; }
 99 
100   static UnsafeMemoryAccess* add_to_table(address start_pc, address end_pc, address error_exit_pc) {
101     guarantee(_table_length < _table_max_length, "Incorrect UnsafeMemoryAccess::_table_max_length");
102     UnsafeMemoryAccess* entry = &_table[_table_length];
103     entry->set_start_pc(start_pc);
104     entry->set_end_pc(end_pc);
105     entry->set_error_exit_pc(error_exit_pc);
106 
107     _table_length++;
108     return entry;
109   }
110 
111   static bool    contains_pc(address pc);
112   static address page_error_continue_pc(address pc);
113   static void    create_table(int max_size);
114 };
115 
116 class UnsafeMemoryAccessMark : public StackObj {
117  private:
118   UnsafeMemoryAccess*  _ucm_entry;
119   StubCodeGenerator* _cgen;
120  public:
121   UnsafeMemoryAccessMark(StubCodeGenerator* cgen, bool add_entry, bool continue_at_scope_end, address error_exit_pc = nullptr);
122   ~UnsafeMemoryAccessMark();
123 };
124 
125 class StubRoutines: AllStatic {
126 
127  public:
128   // Dependencies
129   friend class StubGenerator;
130 
131 #include CPU_HEADER(stubRoutines)
132 
133   static jint    _verify_oop_count;
134   static address _verify_oop_subroutine_entry;
135 
136   static address _call_stub_return_address;                // the return PC, when returning to a call stub
137   static address _call_stub_entry;
138   static address _forward_exception_entry;
139   static address _catch_exception_entry;
140   static address _throw_AbstractMethodError_entry;
141   static address _throw_IncompatibleClassChangeError_entry;
142   static address _throw_NullPointerException_at_call_entry;
143   static address _throw_StackOverflowError_entry;
144   static address _throw_delayed_StackOverflowError_entry;
145 
146   static address _atomic_xchg_entry;
147   static address _atomic_cmpxchg_entry;
148   static address _atomic_cmpxchg_long_entry;
149   static address _atomic_add_entry;
150   static address _fence_entry;
151 
152   static BufferBlob* _initial_stubs_code;                  // code buffer for initial routines
153   static BufferBlob* _continuation_stubs_code;             // code buffer for continuation stubs
154   static BufferBlob* _compiler_stubs_code;                 // code buffer for C2 intrinsics
155   static BufferBlob* _final_stubs_code;                    // code buffer for all other routines
156 
157   static address _array_sort;
158   static address _array_partition;
159   // Leaf routines which implement arraycopy and their addresses
160   // arraycopy operands aligned on element type boundary
161   static address _jbyte_arraycopy;
162   static address _jshort_arraycopy;
163   static address _jint_arraycopy;
164   static address _jlong_arraycopy;
165   static address _oop_arraycopy, _oop_arraycopy_uninit;
166   static address _jbyte_disjoint_arraycopy;
167   static address _jshort_disjoint_arraycopy;
168   static address _jint_disjoint_arraycopy;
169   static address _jlong_disjoint_arraycopy;
170   static address _oop_disjoint_arraycopy, _oop_disjoint_arraycopy_uninit;
171 
172   // arraycopy operands aligned on zero'th element boundary
173   // These are identical to the ones aligned aligned on an
174   // element type boundary, except that they assume that both
175   // source and destination are HeapWord aligned.
176   static address _arrayof_jbyte_arraycopy;
177   static address _arrayof_jshort_arraycopy;
178   static address _arrayof_jint_arraycopy;
179   static address _arrayof_jlong_arraycopy;
180   static address _arrayof_oop_arraycopy, _arrayof_oop_arraycopy_uninit;
181   static address _arrayof_jbyte_disjoint_arraycopy;
182   static address _arrayof_jshort_disjoint_arraycopy;
183   static address _arrayof_jint_disjoint_arraycopy;
184   static address _arrayof_jlong_disjoint_arraycopy;
185   static address _arrayof_oop_disjoint_arraycopy, _arrayof_oop_disjoint_arraycopy_uninit;
186 
187   // cache line writeback
188   static address _data_cache_writeback;
189   static address _data_cache_writeback_sync;
190 
191   // these are recommended but optional:
192   static address _checkcast_arraycopy, _checkcast_arraycopy_uninit;
193   static address _unsafe_arraycopy;
194   static address _generic_arraycopy;
195 
196   static address _unsafe_setmemory;
197 
198   static address _jbyte_fill;
199   static address _jshort_fill;
200   static address _jint_fill;
201   static address _arrayof_jbyte_fill;
202   static address _arrayof_jshort_fill;
203   static address _arrayof_jint_fill;
204 
205   static address _aescrypt_encryptBlock;
206   static address _aescrypt_decryptBlock;
207   static address _cipherBlockChaining_encryptAESCrypt;
208   static address _cipherBlockChaining_decryptAESCrypt;
209   static address _electronicCodeBook_encryptAESCrypt;
210   static address _electronicCodeBook_decryptAESCrypt;
211   static address _counterMode_AESCrypt;
212   static address _galoisCounterMode_AESCrypt;
213   static address _ghash_processBlocks;
214   static address _chacha20Block;
215   static address _base64_encodeBlock;
216   static address _base64_decodeBlock;
217   static address _poly1305_processBlocks;
218   static address _intpoly_montgomeryMult_P256;
219   static address _intpoly_assign;
220 
221   static address _md5_implCompress;
222   static address _md5_implCompressMB;
223   static address _sha1_implCompress;
224   static address _sha1_implCompressMB;
225   static address _sha256_implCompress;
226   static address _sha256_implCompressMB;
227   static address _sha512_implCompress;
228   static address _sha512_implCompressMB;
229   static address _sha3_implCompress;
230   static address _sha3_implCompressMB;
231 
232   static address _updateBytesCRC32;
233   static address _crc_table_adr;
234 
235   static address _string_indexof_array[4];
236 
237   static address _crc32c_table_addr;
238   static address _updateBytesCRC32C;
239   static address _updateBytesAdler32;
240 
241   static address _multiplyToLen;
242   static address _squareToLen;
243   static address _mulAdd;
244   static address _montgomeryMultiply;
245   static address _montgomerySquare;
246   static address _bigIntegerRightShiftWorker;
247   static address _bigIntegerLeftShiftWorker;
248 
249   static address _vectorizedMismatch;
250 
251   static address _dexp;
252   static address _dlog;
253   static address _dlog10;
254   static address _dpow;
255   static address _dsin;
256   static address _dcos;
257   static address _dlibm_sin_cos_huge;
258   static address _dlibm_reduce_pi04l;
259   static address _dlibm_tan_cot_huge;
260   static address _dtan;
261   static address _fmod;
262 
263   static address _f2hf;
264   static address _hf2f;
265 
266   static address _method_entry_barrier;
267 
268   static address _cont_thaw;
269   static address _cont_returnBarrier;
270   static address _cont_returnBarrierExc;
271 
272   JFR_ONLY(static RuntimeStub* _jfr_write_checkpoint_stub;)
273   JFR_ONLY(static address _jfr_write_checkpoint;)
274   JFR_ONLY(static RuntimeStub* _jfr_return_lease_stub;)
275   JFR_ONLY(static address _jfr_return_lease;)
276 
277   // Vector Math Routines
278   static address _vector_f_math[VectorSupport::NUM_VEC_SIZES][VectorSupport::NUM_SVML_OP];
279   static address _vector_d_math[VectorSupport::NUM_VEC_SIZES][VectorSupport::NUM_SVML_OP];
280 
281   static address _upcall_stub_exception_handler;
282 
283   static address _lookup_secondary_supers_table_stubs[];
284   static address _lookup_secondary_supers_table_slow_path_stub;
285 
286  public:
287   // Initialization/Testing
288   static void    initialize_initial_stubs();               // must happen before universe::genesis
289   static void    initialize_continuation_stubs();          // must happen after  universe::genesis
290   static void    initialize_compiler_stubs();              // must happen after  universe::genesis
291   static void    initialize_final_stubs();                 // must happen after  universe::genesis
292 
293   static bool is_stub_code(address addr)                   { return contains(addr); }
294 
295   static bool contains(address addr) {
296     return
297       (_initial_stubs_code      != nullptr && _initial_stubs_code->blob_contains(addr))  ||
298       (_continuation_stubs_code != nullptr && _continuation_stubs_code->blob_contains(addr)) ||
299       (_compiler_stubs_code     != nullptr && _compiler_stubs_code->blob_contains(addr)) ||
300       (_final_stubs_code        != nullptr && _final_stubs_code->blob_contains(addr)) ;
301   }
302 
303   static RuntimeBlob* initial_stubs_code()      { return _initial_stubs_code; }
304   static RuntimeBlob* continuation_stubs_code() { return _continuation_stubs_code; }
305   static RuntimeBlob* compiler_stubs_code()     { return _compiler_stubs_code; }
306   static RuntimeBlob* final_stubs_code()        { return _final_stubs_code; }
307 
308   // Debugging
309   static jint    verify_oop_count()                        { return _verify_oop_count; }
310   static jint*   verify_oop_count_addr()                   { return &_verify_oop_count; }
311   // a subroutine for debugging the GC
312   static address verify_oop_subroutine_entry_address()     { return (address)&_verify_oop_subroutine_entry; }
313 
314   static address catch_exception_entry()                   { return _catch_exception_entry; }
315 
316   // Calls to Java
317   typedef void (*CallStub)(
318     address   link,
319     intptr_t* result,
320     int       result_type, /* BasicType on 4 bytes */
321     Method* method,
322     address   entry_point,
323     intptr_t* parameters,
324     int       size_of_parameters,
325     TRAPS
326   );
327 
328   static CallStub call_stub()                              { return CAST_TO_FN_PTR(CallStub, _call_stub_entry); }
329 
330   // Exceptions
331   static address forward_exception_entry()                 { return _forward_exception_entry; }
332   // Implicit exceptions
333   static address throw_AbstractMethodError_entry()         { return _throw_AbstractMethodError_entry; }
334   static address throw_IncompatibleClassChangeError_entry(){ return _throw_IncompatibleClassChangeError_entry; }
335   static address throw_NullPointerException_at_call_entry(){ return _throw_NullPointerException_at_call_entry; }
336   static address throw_StackOverflowError_entry()          { return _throw_StackOverflowError_entry; }
337   static address throw_delayed_StackOverflowError_entry()  { return _throw_delayed_StackOverflowError_entry; }
338 
339   static address atomic_xchg_entry()                       { return _atomic_xchg_entry; }
340   static address atomic_cmpxchg_entry()                    { return _atomic_cmpxchg_entry; }
341   static address atomic_cmpxchg_long_entry()               { return _atomic_cmpxchg_long_entry; }
342   static address atomic_add_entry()                        { return _atomic_add_entry; }
343   static address fence_entry()                             { return _fence_entry; }
344 
345   static address select_arraycopy_function(BasicType t, bool aligned, bool disjoint, const char* &name, bool dest_uninitialized);
346 
347   static address jbyte_arraycopy()  { return _jbyte_arraycopy; }
348   static address jshort_arraycopy() { return _jshort_arraycopy; }
349   static address jint_arraycopy()   { return _jint_arraycopy; }
350   static address jlong_arraycopy()  { return _jlong_arraycopy; }
351   static address oop_arraycopy(bool dest_uninitialized = false) {
352     return dest_uninitialized ? _oop_arraycopy_uninit : _oop_arraycopy;
353   }
354   static address jbyte_disjoint_arraycopy()  { return _jbyte_disjoint_arraycopy; }
355   static address jshort_disjoint_arraycopy() { return _jshort_disjoint_arraycopy; }
356   static address jint_disjoint_arraycopy()   { return _jint_disjoint_arraycopy; }
357   static address jlong_disjoint_arraycopy()  { return _jlong_disjoint_arraycopy; }
358   static address oop_disjoint_arraycopy(bool dest_uninitialized = false) {
359     return dest_uninitialized ?  _oop_disjoint_arraycopy_uninit : _oop_disjoint_arraycopy;
360   }
361 
362   static address arrayof_jbyte_arraycopy()  { return _arrayof_jbyte_arraycopy; }
363   static address arrayof_jshort_arraycopy() { return _arrayof_jshort_arraycopy; }
364   static address arrayof_jint_arraycopy()   { return _arrayof_jint_arraycopy; }
365   static address arrayof_jlong_arraycopy()  { return _arrayof_jlong_arraycopy; }
366   static address arrayof_oop_arraycopy(bool dest_uninitialized = false) {
367     return dest_uninitialized ? _arrayof_oop_arraycopy_uninit : _arrayof_oop_arraycopy;
368   }
369 
370   static address arrayof_jbyte_disjoint_arraycopy()  { return _arrayof_jbyte_disjoint_arraycopy; }
371   static address arrayof_jshort_disjoint_arraycopy() { return _arrayof_jshort_disjoint_arraycopy; }
372   static address arrayof_jint_disjoint_arraycopy()   { return _arrayof_jint_disjoint_arraycopy; }
373   static address arrayof_jlong_disjoint_arraycopy()  { return _arrayof_jlong_disjoint_arraycopy; }
374   static address arrayof_oop_disjoint_arraycopy(bool dest_uninitialized = false) {
375     return dest_uninitialized ? _arrayof_oop_disjoint_arraycopy_uninit : _arrayof_oop_disjoint_arraycopy;
376   }
377   static address data_cache_writeback()              { return _data_cache_writeback; }
378   static address data_cache_writeback_sync()         { return _data_cache_writeback_sync; }
379 
380   typedef void (*DataCacheWritebackStub)(void *);
381   static DataCacheWritebackStub DataCacheWriteback_stub()         { return CAST_TO_FN_PTR(DataCacheWritebackStub,  _data_cache_writeback); }
382   typedef void (*DataCacheWritebackSyncStub)(bool);
383   static DataCacheWritebackSyncStub DataCacheWritebackSync_stub() { return CAST_TO_FN_PTR(DataCacheWritebackSyncStub,  _data_cache_writeback_sync); }
384 
385   static address checkcast_arraycopy(bool dest_uninitialized = false) {
386     return dest_uninitialized ? _checkcast_arraycopy_uninit : _checkcast_arraycopy;
387   }
388   static address unsafe_arraycopy()     { return _unsafe_arraycopy; }
389 
390   typedef void (*UnsafeArrayCopyStub)(const void* src, void* dst, size_t count);
391   static UnsafeArrayCopyStub UnsafeArrayCopy_stub()         { return CAST_TO_FN_PTR(UnsafeArrayCopyStub,  _unsafe_arraycopy); }
392 
393   static address unsafe_setmemory()     { return _unsafe_setmemory; }
394 
395   typedef void (*UnsafeSetMemoryStub)(const void* src, size_t count, char byte);
396   static UnsafeSetMemoryStub UnsafeSetMemory_stub()         { return CAST_TO_FN_PTR(UnsafeSetMemoryStub,  _unsafe_setmemory); }
397 
398   static address generic_arraycopy()   { return _generic_arraycopy; }
399   static address select_arraysort_function() { return _array_sort; }
400   static address select_array_partition_function() { return _array_partition; }
401 
402   static address jbyte_fill()          { return _jbyte_fill; }
403   static address jshort_fill()         { return _jshort_fill; }
404   static address jint_fill()           { return _jint_fill; }
405   static address arrayof_jbyte_fill()  { return _arrayof_jbyte_fill; }
406   static address arrayof_jshort_fill() { return _arrayof_jshort_fill; }
407   static address arrayof_jint_fill()   { return _arrayof_jint_fill; }
408 
409   static address aescrypt_encryptBlock()                { return _aescrypt_encryptBlock; }
410   static address aescrypt_decryptBlock()                { return _aescrypt_decryptBlock; }
411   static address cipherBlockChaining_encryptAESCrypt()  { return _cipherBlockChaining_encryptAESCrypt; }
412   static address cipherBlockChaining_decryptAESCrypt()  { return _cipherBlockChaining_decryptAESCrypt; }
413   static address electronicCodeBook_encryptAESCrypt()   { return _electronicCodeBook_encryptAESCrypt; }
414   static address electronicCodeBook_decryptAESCrypt()   { return _electronicCodeBook_decryptAESCrypt; }
415   static address poly1305_processBlocks()               { return _poly1305_processBlocks; }
416   static address intpoly_montgomeryMult_P256()          { return _intpoly_montgomeryMult_P256; }
417   static address intpoly_assign()        { return _intpoly_assign; }
418   static address counterMode_AESCrypt()  { return _counterMode_AESCrypt; }
419   static address ghash_processBlocks()   { return _ghash_processBlocks; }
420   static address chacha20Block()         { return _chacha20Block; }
421   static address base64_encodeBlock()    { return _base64_encodeBlock; }
422   static address base64_decodeBlock()    { return _base64_decodeBlock; }
423   static address md5_implCompress()      { return _md5_implCompress; }
424   static address md5_implCompressMB()    { return _md5_implCompressMB; }
425   static address sha1_implCompress()     { return _sha1_implCompress; }
426   static address sha1_implCompressMB()   { return _sha1_implCompressMB; }
427   static address sha256_implCompress()   { return _sha256_implCompress; }
428   static address sha256_implCompressMB() { return _sha256_implCompressMB; }
429   static address sha512_implCompress()   { return _sha512_implCompress; }
430   static address sha512_implCompressMB() { return _sha512_implCompressMB; }
431   static address sha3_implCompress()     { return _sha3_implCompress; }
432   static address sha3_implCompressMB()   { return _sha3_implCompressMB; }
433 
434   static address updateBytesCRC32()    { return _updateBytesCRC32; }
435   static address crc_table_addr()      { return _crc_table_adr; }
436 
437   static address crc32c_table_addr()   { return _crc32c_table_addr; }
438   static address updateBytesCRC32C()   { return _updateBytesCRC32C; }
439   static address updateBytesAdler32()  { return _updateBytesAdler32; }
440 
441   static address multiplyToLen()       { return _multiplyToLen; }
442   static address squareToLen()         { return _squareToLen; }
443   static address mulAdd()              { return _mulAdd; }
444   static address montgomeryMultiply()  { return _montgomeryMultiply; }
445   static address montgomerySquare()    { return _montgomerySquare; }
446   static address bigIntegerRightShift() { return _bigIntegerRightShiftWorker; }
447   static address bigIntegerLeftShift()  { return _bigIntegerLeftShiftWorker; }
448   static address galoisCounterMode_AESCrypt()   { return _galoisCounterMode_AESCrypt; }
449 
450   static address vectorizedMismatch()  { return _vectorizedMismatch; }
451 
452   static address dexp()                { return _dexp; }
453   static address dlog()                { return _dlog; }
454   static address dlog10()              { return _dlog10; }
455   static address dpow()                { return _dpow; }
456   static address fmod()                { return _fmod; }
457   static address dsin()                { return _dsin; }
458   static address dcos()                { return _dcos; }
459   static address dlibm_reduce_pi04l()  { return _dlibm_reduce_pi04l; }
460   static address dlibm_sin_cos_huge()  { return _dlibm_sin_cos_huge; }
461   static address dlibm_tan_cot_huge()  { return _dlibm_tan_cot_huge; }
462   static address dtan()                { return _dtan; }
463 
464   // These are versions of the java.lang.Float::floatToFloat16() and float16ToFloat()
465   // methods which perform the same operations as the intrinsic version.
466   // They are used for constant folding in JIT compiler to ensure equivalence.
467   //
468   static address f2hf_adr()            { return _f2hf; }
469   static address hf2f_adr()            { return _hf2f; }
470 
471   static jshort f2hf(jfloat x) {
472     assert(_f2hf != nullptr, "stub is not implemented on this platform");
473     MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, Thread::current());) // About to call into code cache
474     typedef jshort (*f2hf_stub_t)(jfloat x);
475     return ((f2hf_stub_t)_f2hf)(x);
476   }
477   static jfloat hf2f(jshort x) {
478     assert(_hf2f != nullptr, "stub is not implemented on this platform");
479     MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, Thread::current());) // About to call into code cache
480     typedef jfloat (*hf2f_stub_t)(jshort x);
481     return ((hf2f_stub_t)_hf2f)(x);
482   }
483 
484   static address method_entry_barrier() { return _method_entry_barrier; }
485 
486   static address cont_thaw()           { return _cont_thaw; }
487   static address cont_returnBarrier()  { return _cont_returnBarrier; }
488   static address cont_returnBarrierExc(){return _cont_returnBarrierExc; }
489 
490   JFR_ONLY(static address jfr_write_checkpoint() { return _jfr_write_checkpoint; })
491   JFR_ONLY(static address jfr_return_lease() { return _jfr_return_lease; })
492 
493   static address upcall_stub_exception_handler() {
494     assert(_upcall_stub_exception_handler != nullptr, "not implemented");
495     return _upcall_stub_exception_handler;
496   }
497 
498   static address lookup_secondary_supers_table_stub(u1 slot) {
499     assert(slot < Klass::SECONDARY_SUPERS_TABLE_SIZE, "out of bounds");
500     assert(_lookup_secondary_supers_table_stubs[slot] != nullptr, "not implemented");
501     return _lookup_secondary_supers_table_stubs[slot];
502   }
503 
504   static address lookup_secondary_supers_table_slow_path_stub() {
505     assert(_lookup_secondary_supers_table_slow_path_stub != nullptr, "not implemented");
506     return _lookup_secondary_supers_table_slow_path_stub;
507   }
508 
509   static address select_fill_function(BasicType t, bool aligned, const char* &name);
510 
511   //
512   // Default versions of the above arraycopy functions for platforms which do
513   // not have specialized versions
514   //
515   static void jbyte_copy     (jbyte*  src, jbyte*  dest, size_t count);
516   static void jshort_copy    (jshort* src, jshort* dest, size_t count);
517   static void jint_copy      (jint*   src, jint*   dest, size_t count);
518   static void jlong_copy     (jlong*  src, jlong*  dest, size_t count);
519   static void oop_copy       (oop*    src, oop*    dest, size_t count);
520   static void oop_copy_uninit(oop*    src, oop*    dest, size_t count);
521 
522   static void arrayof_jbyte_copy     (HeapWord* src, HeapWord* dest, size_t count);
523   static void arrayof_jshort_copy    (HeapWord* src, HeapWord* dest, size_t count);
524   static void arrayof_jint_copy      (HeapWord* src, HeapWord* dest, size_t count);
525   static void arrayof_jlong_copy     (HeapWord* src, HeapWord* dest, size_t count);
526   static void arrayof_oop_copy       (HeapWord* src, HeapWord* dest, size_t count);
527   static void arrayof_oop_copy_uninit(HeapWord* src, HeapWord* dest, size_t count);
528 };
529 
530 #endif // SHARE_RUNTIME_STUBROUTINES_HPP