1 /*
  2  * Copyright (c) 1998, 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_CODE_CODEBLOB_HPP
 26 #define SHARE_CODE_CODEBLOB_HPP
 27 
 28 #include "asm/codeBuffer.hpp"
 29 #include "compiler/compilerDefinitions.hpp"
 30 #include "compiler/oopMap.hpp"
 31 #include "runtime/javaFrameAnchor.hpp"
 32 #include "runtime/frame.hpp"
 33 #include "runtime/handles.hpp"
 34 #include "utilities/align.hpp"
 35 #include "utilities/macros.hpp"
 36 
 37 class ImmutableOopMap;
 38 class ImmutableOopMapSet;
 39 class JNIHandleBlock;
 40 class OopMapSet;
 41 
 42 // CodeBlob Types
 43 // Used in the CodeCache to assign CodeBlobs to different CodeHeaps
 44 enum class CodeBlobType {
 45   MethodNonProfiled   = 0,    // Execution level 1 and 4 (non-profiled) nmethods (including native nmethods)
 46   MethodProfiled      = 1,    // Execution level 2 and 3 (profiled) nmethods
 47   NonNMethod          = 2,    // Non-nmethods like Buffers, Adapters and Runtime Stubs
 48   All                 = 3,    // All types (No code cache segmentation)
 49   NumTypes            = 4     // Number of CodeBlobTypes
 50 };
 51 
 52 // CodeBlob - superclass for all entries in the CodeCache.
 53 //
 54 // Subtypes are:
 55 //  CompiledMethod       : Compiled Java methods (include method that calls to native code)
 56 //   nmethod             : JIT Compiled Java methods
 57 //  RuntimeBlob          : Non-compiled method code; generated glue code
 58 //   BufferBlob          : Used for non-relocatable code such as interpreter, stubroutines, etc.
 59 //    AdapterBlob        : Used to hold C2I/I2C adapters
 60 //    VtableBlob         : Used for holding vtable chunks
 61 //    MethodHandlesAdapterBlob : Used to hold MethodHandles adapters
 62 //   RuntimeStub         : Call to VM runtime methods
 63 //   SingletonBlob       : Super-class for all blobs that exist in only one instance
 64 //    DeoptimizationBlob : Used for deoptimization
 65 //    ExceptionBlob      : Used for stack unrolling
 66 //    SafepointBlob      : Used to handle illegal instruction exceptions
 67 //    UncommonTrapBlob   : Used to handle uncommon traps
 68 //   UpcallStub  : Used for upcalls from native code
 69 //
 70 //
 71 // Layout : continuous in the CodeCache
 72 //   - header
 73 //   - relocation
 74 //   - content space
 75 //     - instruction space
 76 //   - data space
 77 
 78 
 79 class CodeBlobLayout;
 80 class UpcallStub; // for as_upcall_stub()
 81 class RuntimeStub; // for as_runtime_stub()
 82 class JavaFrameAnchor; // for UpcallStub::jfa_for_frame
 83 
 84 class CodeBlob {
 85   friend class VMStructs;
 86   friend class JVMCIVMStructs;
 87   friend class CodeCacheDumper;
 88 
 89 protected:
 90 
 91   // order fields from large to small to minimize padding between fields
 92   address    _code_begin;
 93   address    _code_end;
 94   address    _content_begin;                     // address to where content region begins (this includes consts, insts, stubs)
 95                                                  // address    _content_end - not required, for all CodeBlobs _code_end == _content_end for now
 96   address    _data_end;
 97   address    _relocation_begin;
 98   address    _relocation_end;
 99 
100   ImmutableOopMapSet* _oop_maps;                 // OopMap for this CodeBlob
101 
102   const char*         _name;
103   S390_ONLY(int       _ctable_offset;)
104 
105   int        _size;                              // total size of CodeBlob in bytes
106   int        _header_size;                       // size of header (depends on subclass)
107   int        _frame_complete_offset;             // instruction offsets in [0.._frame_complete_offset) have
108                                                  // not finished setting up their frame. Beware of pc's in
109                                                  // that range. There is a similar range(s) on returns
110                                                  // which we don't detect.
111   int        _data_offset;                       // offset to where data region begins
112   int        _frame_size;                        // size of stack frame in words (NOT slots. On x64 these are 64bit words)
113 
114   bool                _caller_must_gc_arguments;
115 
116   bool                _is_compiled;
117   const CompilerType  _type;                     // CompilerType
118 
119 #ifndef PRODUCT
120   AsmRemarks _asm_remarks;
121   DbgStrings _dbg_strings;
122 #endif // not PRODUCT
123 
124   CodeBlob(const char* name, CompilerType type, const CodeBlobLayout& layout, int frame_complete_offset,
125            int frame_size, ImmutableOopMapSet* oop_maps,
126            bool caller_must_gc_arguments, bool compiled = false);
127   CodeBlob(const char* name, CompilerType type, const CodeBlobLayout& layout, CodeBuffer* cb, int frame_complete_offset,
128            int frame_size, OopMapSet* oop_maps,
129            bool caller_must_gc_arguments, bool compiled = false);
130 
131   void operator delete(void* p) { }
132 
133 public:
134   // Only used by unit test.
135   CodeBlob() : _type(compiler_none) {}
136 
137   virtual ~CodeBlob() {
138     assert(_oop_maps == nullptr, "Not flushed");
139   }
140 
141   // Returns the space needed for CodeBlob
142   static unsigned int allocation_size(CodeBuffer* cb, int header_size);
143   static unsigned int align_code_offset(int offset);
144 
145   // Deletion
146   virtual void purge(bool free_code_cache_data, bool unregister_nmethod);
147 
148   // Typing
149   virtual bool is_buffer_blob() const                 { return false; }
150   virtual bool is_nmethod() const                     { return false; }
151   virtual bool is_runtime_stub() const                { return false; }
152   virtual bool is_deoptimization_stub() const         { return false; }
153   virtual bool is_uncommon_trap_stub() const          { return false; }
154   virtual bool is_exception_stub() const              { return false; }
155   virtual bool is_safepoint_stub() const              { return false; }
156   virtual bool is_adapter_blob() const                { return false; }
157   virtual bool is_vtable_blob() const                 { return false; }
158   virtual bool is_method_handles_adapter_blob() const { return false; }
159   virtual bool is_upcall_stub() const                 { return false; }
160   bool is_compiled() const                            { return _is_compiled; }
161   const bool* is_compiled_addr() const                { return &_is_compiled; }
162 
163   inline bool is_compiled_by_c1() const    { return _type == compiler_c1; };
164   inline bool is_compiled_by_c2() const    { return _type == compiler_c2; };
165   inline bool is_compiled_by_jvmci() const { return _type == compiler_jvmci; };
166   const char* compiler_name() const;
167   CompilerType compiler_type() const { return _type; }
168 
169   // Casting
170   nmethod* as_nmethod_or_null()                { return is_nmethod() ? (nmethod*) this : nullptr; }
171   nmethod* as_nmethod()                        { assert(is_nmethod(), "must be nmethod"); return (nmethod*) this; }
172   CompiledMethod* as_compiled_method_or_null() { return is_compiled() ? (CompiledMethod*) this : nullptr; }
173   CompiledMethod* as_compiled_method()         { assert(is_compiled(), "must be compiled"); return (CompiledMethod*) this; }
174   CodeBlob* as_codeblob_or_null() const        { return (CodeBlob*) this; }
175   UpcallStub* as_upcall_stub() const           { assert(is_upcall_stub(), "must be upcall stub"); return (UpcallStub*) this; }
176   RuntimeStub* as_runtime_stub() const         { assert(is_runtime_stub(), "must be runtime blob"); return (RuntimeStub*) this; }
177 
178   // Boundaries
179   address header_begin() const        { return (address) this; }
180   relocInfo* relocation_begin() const { return (relocInfo*) _relocation_begin; };
181   relocInfo* relocation_end() const   { return (relocInfo*) _relocation_end; }
182   address content_begin() const       { return _content_begin; }
183   address content_end() const         { return _code_end; } // _code_end == _content_end is true for all types of blobs for now, it is also checked in the constructor
184   address code_begin() const          { return _code_begin;    }
185   address code_end() const            { return _code_end; }
186   address data_end() const            { return _data_end;      }
187 
188   // This field holds the beginning of the const section in the old code buffer.
189   // It is needed to fix relocations of pc-relative loads when resizing the
190   // the constant pool or moving it.
191   S390_ONLY(address ctable_begin() const { return header_begin() + _ctable_offset; })
192   void set_ctable_begin(address ctable) { S390_ONLY(_ctable_offset = ctable - header_begin();) }
193 
194   // Sizes
195   int size() const                               { return _size; }
196   int header_size() const                        { return _header_size; }
197   int relocation_size() const                    { return pointer_delta_as_int((address) relocation_end(), (address) relocation_begin()); }
198   int content_size() const                       { return pointer_delta_as_int(content_end(), content_begin()); }
199   int code_size() const                          { return pointer_delta_as_int(code_end(), code_begin()); }
200   // Only used from CodeCache::free_unused_tail() after the Interpreter blob was trimmed
201   void adjust_size(size_t used) {
202     _size = (int)used;
203     _data_offset = (int)used;
204     _code_end = (address)this + used;
205     _data_end = (address)this + used;
206   }
207 
208   // Containment
209   bool blob_contains(address addr) const         { return header_begin()       <= addr && addr < data_end();       }
210   bool code_contains(address addr) const         { return code_begin()         <= addr && addr < code_end();       }
211   bool contains(address addr) const              { return content_begin()      <= addr && addr < content_end();    }
212   bool is_frame_complete_at(address addr) const  { return _frame_complete_offset != CodeOffsets::frame_never_safe &&
213                                                           code_contains(addr) && addr >= code_begin() + _frame_complete_offset; }
214   int frame_complete_offset() const              { return _frame_complete_offset; }
215 
216   virtual bool is_not_entrant() const            { return false; }
217 
218   // OopMap for frame
219   ImmutableOopMapSet* oop_maps() const           { return _oop_maps; }
220   void set_oop_maps(OopMapSet* p);
221 
222   const ImmutableOopMap* oop_map_for_slot(int slot, address return_address) const;
223   const ImmutableOopMap* oop_map_for_return_address(address return_address) const;
224   virtual void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f) = 0;
225 
226   // Frame support. Sizes are in word units.
227   int  frame_size() const                        { return _frame_size; }
228   void set_frame_size(int size)                  { _frame_size = size; }
229 
230   // Returns true, if the next frame is responsible for GC'ing oops passed as arguments
231   bool caller_must_gc_arguments(JavaThread* thread) const { return _caller_must_gc_arguments; }
232 
233   // Naming
234   const char* name() const                       { return _name; }
235   void set_name(const char* name)                { _name = name; }
236 
237   // Debugging
238   virtual void verify() = 0;
239   virtual void print() const;
240   virtual void print_on(outputStream* st) const;
241   virtual void print_value_on(outputStream* st) const;
242   void dump_for_addr(address addr, outputStream* st, bool verbose) const;
243   void print_code_on(outputStream* st);
244 
245   // Print to stream, any comments associated with offset.
246   virtual void print_block_comment(outputStream* stream, address block_begin) const {
247 #ifndef PRODUCT
248     ptrdiff_t offset = block_begin - code_begin();
249     assert(offset >= 0, "Expecting non-negative offset!");
250     _asm_remarks.print(uint(offset), stream);
251 #endif
252   }
253 
254 #ifndef PRODUCT
255   AsmRemarks &asm_remarks() { return _asm_remarks; }
256   DbgStrings &dbg_strings() { return _dbg_strings; }
257 
258   void use_remarks(AsmRemarks &remarks) { _asm_remarks.share(remarks); }
259   void use_strings(DbgStrings &strings) { _dbg_strings.share(strings); }
260 #endif
261 };
262 
263 class CodeBlobLayout : public StackObj {
264 private:
265   int _size;
266   int _header_size;
267   int _relocation_size;
268   int _content_offset;
269   int _code_offset;
270   int _data_offset;
271   address _code_begin;
272   address _code_end;
273   address _content_begin;
274   address _content_end;
275   address _data_end;
276   address _relocation_begin;
277   address _relocation_end;
278 
279 public:
280   CodeBlobLayout(address code_begin, address code_end, address content_begin, address content_end, address data_end, address relocation_begin, address relocation_end) :
281     _size(0),
282     _header_size(0),
283     _relocation_size(0),
284     _content_offset(0),
285     _code_offset(0),
286     _data_offset(0),
287     _code_begin(code_begin),
288     _code_end(code_end),
289     _content_begin(content_begin),
290     _content_end(content_end),
291     _data_end(data_end),
292     _relocation_begin(relocation_begin),
293     _relocation_end(relocation_end)
294   {
295   }
296 
297   CodeBlobLayout(const address start, int size, int header_size, int relocation_size, int data_offset) :
298     _size(size),
299     _header_size(header_size),
300     _relocation_size(relocation_size),
301     _content_offset(CodeBlob::align_code_offset(_header_size + _relocation_size)),
302     _code_offset(_content_offset),
303     _data_offset(data_offset)
304   {
305     assert(is_aligned(_relocation_size, oopSize), "unaligned size");
306 
307     _code_begin = (address) start + _code_offset;
308     _code_end = (address) start + _data_offset;
309 
310     _content_begin = (address) start + _content_offset;
311     _content_end = (address) start + _data_offset;
312 
313     _data_end = (address) start + _size;
314     _relocation_begin = (address) start + _header_size;
315     _relocation_end = _relocation_begin + _relocation_size;
316   }
317 
318   CodeBlobLayout(const address start, int size, int header_size, const CodeBuffer* cb) :
319     _size(size),
320     _header_size(header_size),
321     _relocation_size(align_up(cb->total_relocation_size(), oopSize)),
322     _content_offset(CodeBlob::align_code_offset(_header_size + _relocation_size)),
323     _code_offset(_content_offset + cb->total_offset_of(cb->insts())),
324     _data_offset(_content_offset + align_up(cb->total_content_size(), oopSize))
325   {
326     assert(is_aligned(_relocation_size, oopSize), "unaligned size");
327 
328     _code_begin = (address) start + _code_offset;
329     _code_end = (address) start + _data_offset;
330 
331     _content_begin = (address) start + _content_offset;
332     _content_end = (address) start + _data_offset;
333 
334     _data_end = (address) start + _size;
335     _relocation_begin = (address) start + _header_size;
336     _relocation_end = _relocation_begin + _relocation_size;
337   }
338 
339   int size() const { return _size; }
340   int header_size() const { return _header_size; }
341   int relocation_size() const { return _relocation_size; }
342   int content_offset() const { return _content_offset; }
343   int code_offset() const { return _code_offset; }
344   int data_offset() const { return _data_offset; }
345   address code_begin() const { return _code_begin; }
346   address code_end() const { return _code_end; }
347   address data_end() const { return _data_end; }
348   address relocation_begin() const { return _relocation_begin; }
349   address relocation_end() const { return _relocation_end; }
350   address content_begin() const { return _content_begin; }
351   address content_end() const { return _content_end; }
352 };
353 
354 
355 class RuntimeBlob : public CodeBlob {
356   friend class VMStructs;
357  public:
358 
359   // Creation
360   // a) simple CodeBlob
361   // frame_complete is the offset from the beginning of the instructions
362   // to where the frame setup (from stackwalk viewpoint) is complete.
363   RuntimeBlob(const char* name, int header_size, int size, int frame_complete, int locs_size);
364 
365   // b) full CodeBlob
366   RuntimeBlob(
367     const char* name,
368     CodeBuffer* cb,
369     int         header_size,
370     int         size,
371     int         frame_complete,
372     int         frame_size,
373     OopMapSet*  oop_maps,
374     bool        caller_must_gc_arguments = false
375   );
376 
377   static void free(RuntimeBlob* blob);
378 
379   void verify();
380 
381   // OopMap for frame
382   virtual void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { ShouldNotReachHere(); }
383 
384   // Debugging
385   virtual void print_on(outputStream* st) const { CodeBlob::print_on(st); }
386   virtual void print_value_on(outputStream* st) const { CodeBlob::print_value_on(st); }
387 
388   // Deal with Disassembler, VTune, Forte, JvmtiExport, MemoryService.
389   static void trace_new_stub(RuntimeBlob* blob, const char* name1, const char* name2 = "");
390 };
391 
392 class WhiteBox;
393 //----------------------------------------------------------------------------------------------------
394 // BufferBlob: used to hold non-relocatable machine code such as the interpreter, stubroutines, etc.
395 
396 class BufferBlob: public RuntimeBlob {
397   friend class VMStructs;
398   friend class AdapterBlob;
399   friend class VtableBlob;
400   friend class MethodHandlesAdapterBlob;
401   friend class UpcallStub;
402   friend class WhiteBox;
403 
404  private:
405   // Creation support
406   BufferBlob(const char* name, int size);
407   BufferBlob(const char* name, int size, CodeBuffer* cb);
408 
409   void* operator new(size_t s, unsigned size) throw();
410 
411  public:
412   // Creation
413   static BufferBlob* create(const char* name, uint buffer_size);
414   static BufferBlob* create(const char* name, CodeBuffer* cb);
415 
416   static void free(BufferBlob* buf);
417 
418   // Typing
419   virtual bool is_buffer_blob() const            { return true; }
420 
421   // GC/Verification support
422   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }
423 
424   void verify();
425   void print_on(outputStream* st) const;
426   void print_value_on(outputStream* st) const;
427 };
428 
429 
430 //----------------------------------------------------------------------------------------------------
431 // AdapterBlob: used to hold C2I/I2C adapters
432 
433 class AdapterBlob: public BufferBlob {
434 private:
435   AdapterBlob(int size, CodeBuffer* cb);
436 
437 public:
438   // Creation
439   static AdapterBlob* create(CodeBuffer* cb);
440 
441   // Typing
442   virtual bool is_adapter_blob() const { return true; }
443 };
444 
445 //---------------------------------------------------------------------------------------------------
446 class VtableBlob: public BufferBlob {
447 private:
448   VtableBlob(const char*, int);
449 
450   void* operator new(size_t s, unsigned size) throw();
451 
452 public:
453   // Creation
454   static VtableBlob* create(const char* name, int buffer_size);
455 
456   // Typing
457   virtual bool is_vtable_blob() const { return true; }
458 };
459 
460 //----------------------------------------------------------------------------------------------------
461 // MethodHandlesAdapterBlob: used to hold MethodHandles adapters
462 
463 class MethodHandlesAdapterBlob: public BufferBlob {
464 private:
465   MethodHandlesAdapterBlob(int size): BufferBlob("MethodHandles adapters", size) {}
466 
467 public:
468   // Creation
469   static MethodHandlesAdapterBlob* create(int buffer_size);
470 
471   // Typing
472   virtual bool is_method_handles_adapter_blob() const { return true; }
473 };
474 
475 
476 //----------------------------------------------------------------------------------------------------
477 // RuntimeStub: describes stubs used by compiled code to call a (static) C++ runtime routine
478 
479 class RuntimeStub: public RuntimeBlob {
480   friend class VMStructs;
481  private:
482   // Creation support
483   RuntimeStub(
484     const char* name,
485     CodeBuffer* cb,
486     int         size,
487     int         frame_complete,
488     int         frame_size,
489     OopMapSet*  oop_maps,
490     bool        caller_must_gc_arguments
491   );
492 
493   void* operator new(size_t s, unsigned size) throw();
494 
495  public:
496   // Creation
497   static RuntimeStub* new_runtime_stub(
498     const char* stub_name,
499     CodeBuffer* cb,
500     int         frame_complete,
501     int         frame_size,
502     OopMapSet*  oop_maps,
503     bool        caller_must_gc_arguments,
504     bool        alloc_fail_is_fatal=true
505   );
506 
507   static void free(RuntimeStub* stub) { RuntimeBlob::free(stub); }
508 
509   // Typing
510   bool is_runtime_stub() const                   { return true; }
511 
512   address entry_point() const                    { return code_begin(); }
513 
514   // GC/Verification support
515   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f)  { /* nothing to do */ }
516 
517   void verify();
518   void print_on(outputStream* st) const;
519   void print_value_on(outputStream* st) const;
520 };
521 
522 
523 //----------------------------------------------------------------------------------------------------
524 // Super-class for all blobs that exist in only one instance. Implements default behaviour.
525 
526 class SingletonBlob: public RuntimeBlob {
527   friend class VMStructs;
528 
529  protected:
530   void* operator new(size_t s, unsigned size) throw();
531 
532  public:
533    SingletonBlob(
534      const char* name,
535      CodeBuffer* cb,
536      int         header_size,
537      int         size,
538      int         frame_size,
539      OopMapSet*  oop_maps
540    )
541    : RuntimeBlob(name, cb, header_size, size, CodeOffsets::frame_never_safe, frame_size, oop_maps)
542   {};
543 
544   address entry_point()                          { return code_begin(); }
545 
546   // GC/Verification support
547   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f)  { /* nothing to do */ }
548   void verify(); // does nothing
549   void print_on(outputStream* st) const;
550   void print_value_on(outputStream* st) const;
551 };
552 
553 
554 //----------------------------------------------------------------------------------------------------
555 // DeoptimizationBlob
556 
557 class DeoptimizationBlob: public SingletonBlob {
558   friend class VMStructs;
559   friend class JVMCIVMStructs;
560  private:
561   int _unpack_offset;
562   int _unpack_with_exception;
563   int _unpack_with_reexecution;
564 
565   int _unpack_with_exception_in_tls;
566 
567 #if INCLUDE_JVMCI
568   // Offsets when JVMCI calls uncommon_trap.
569   int _uncommon_trap_offset;
570   int _implicit_exception_uncommon_trap_offset;
571 #endif
572 
573   // Creation support
574   DeoptimizationBlob(
575     CodeBuffer* cb,
576     int         size,
577     OopMapSet*  oop_maps,
578     int         unpack_offset,
579     int         unpack_with_exception_offset,
580     int         unpack_with_reexecution_offset,
581     int         frame_size
582   );
583 
584  public:
585   // Creation
586   static DeoptimizationBlob* create(
587     CodeBuffer* cb,
588     OopMapSet*  oop_maps,
589     int         unpack_offset,
590     int         unpack_with_exception_offset,
591     int         unpack_with_reexecution_offset,
592     int         frame_size
593   );
594 
595   // Typing
596   bool is_deoptimization_stub() const { return true; }
597 
598   // GC for args
599   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) { /* Nothing to do */ }
600 
601   // Printing
602   void print_value_on(outputStream* st) const;
603 
604   address unpack() const                         { return code_begin() + _unpack_offset;           }
605   address unpack_with_exception() const          { return code_begin() + _unpack_with_exception;   }
606   address unpack_with_reexecution() const        { return code_begin() + _unpack_with_reexecution; }
607 
608   // Alternate entry point for C1 where the exception and issuing pc
609   // are in JavaThread::_exception_oop and JavaThread::_exception_pc
610   // instead of being in registers.  This is needed because C1 doesn't
611   // model exception paths in a way that keeps these registers free so
612   // there may be live values in those registers during deopt.
613   void set_unpack_with_exception_in_tls_offset(int offset) {
614     _unpack_with_exception_in_tls = offset;
615     assert(code_contains(code_begin() + _unpack_with_exception_in_tls), "must be PC inside codeblob");
616   }
617   address unpack_with_exception_in_tls() const   { return code_begin() + _unpack_with_exception_in_tls; }
618 
619 #if INCLUDE_JVMCI
620   // Offsets when JVMCI calls uncommon_trap.
621   void set_uncommon_trap_offset(int offset) {
622     _uncommon_trap_offset = offset;
623     assert(contains(code_begin() + _uncommon_trap_offset), "must be PC inside codeblob");
624   }
625   address uncommon_trap() const                  { return code_begin() + _uncommon_trap_offset; }
626 
627   void set_implicit_exception_uncommon_trap_offset(int offset) {
628     _implicit_exception_uncommon_trap_offset = offset;
629     assert(contains(code_begin() + _implicit_exception_uncommon_trap_offset), "must be PC inside codeblob");
630   }
631   address implicit_exception_uncommon_trap() const { return code_begin() + _implicit_exception_uncommon_trap_offset; }
632 #endif // INCLUDE_JVMCI
633 };
634 
635 
636 //----------------------------------------------------------------------------------------------------
637 // UncommonTrapBlob (currently only used by Compiler 2)
638 
639 #ifdef COMPILER2
640 
641 class UncommonTrapBlob: public SingletonBlob {
642   friend class VMStructs;
643  private:
644   // Creation support
645   UncommonTrapBlob(
646     CodeBuffer* cb,
647     int         size,
648     OopMapSet*  oop_maps,
649     int         frame_size
650   );
651 
652  public:
653   // Creation
654   static UncommonTrapBlob* create(
655     CodeBuffer* cb,
656     OopMapSet*  oop_maps,
657     int         frame_size
658   );
659 
660   // GC for args
661   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f)  { /* nothing to do */ }
662 
663   // Typing
664   bool is_uncommon_trap_stub() const             { return true; }
665 };
666 
667 
668 //----------------------------------------------------------------------------------------------------
669 // ExceptionBlob: used for exception unwinding in compiled code (currently only used by Compiler 2)
670 
671 class ExceptionBlob: public SingletonBlob {
672   friend class VMStructs;
673  private:
674   // Creation support
675   ExceptionBlob(
676     CodeBuffer* cb,
677     int         size,
678     OopMapSet*  oop_maps,
679     int         frame_size
680   );
681 
682  public:
683   // Creation
684   static ExceptionBlob* create(
685     CodeBuffer* cb,
686     OopMapSet*  oop_maps,
687     int         frame_size
688   );
689 
690   // GC for args
691   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }
692 
693   // Typing
694   bool is_exception_stub() const                 { return true; }
695 };
696 #endif // COMPILER2
697 
698 
699 //----------------------------------------------------------------------------------------------------
700 // SafepointBlob: handles illegal_instruction exceptions during a safepoint
701 
702 class SafepointBlob: public SingletonBlob {
703   friend class VMStructs;
704  private:
705   // Creation support
706   SafepointBlob(
707     CodeBuffer* cb,
708     int         size,
709     OopMapSet*  oop_maps,
710     int         frame_size
711   );
712 
713  public:
714   // Creation
715   static SafepointBlob* create(
716     CodeBuffer* cb,
717     OopMapSet*  oop_maps,
718     int         frame_size
719   );
720 
721   // GC for args
722   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }
723 
724   // Typing
725   bool is_safepoint_stub() const                 { return true; }
726 };
727 
728 //----------------------------------------------------------------------------------------------------
729 
730 class UpcallLinker;
731 
732 // A (Panama) upcall stub. Not used by JNI.
733 class UpcallStub: public RuntimeBlob {
734   friend class UpcallLinker;
735  private:
736   jobject _receiver;
737   ByteSize _frame_data_offset;
738 
739   UpcallStub(const char* name, CodeBuffer* cb, int size, jobject receiver, ByteSize frame_data_offset);
740 
741   void* operator new(size_t s, unsigned size) throw();
742 
743   struct FrameData {
744     JavaFrameAnchor jfa;
745     JavaThread* thread;
746     JNIHandleBlock* old_handles;
747     JNIHandleBlock* new_handles;
748   };
749 
750   // defined in frame_ARCH.cpp
751   FrameData* frame_data_for_frame(const frame& frame) const;
752  public:
753   // Creation
754   static UpcallStub* create(const char* name, CodeBuffer* cb, jobject receiver, ByteSize frame_data_offset);
755 
756   static void free(UpcallStub* blob);
757 
758   jobject receiver() { return _receiver; }
759 
760   JavaFrameAnchor* jfa_for_frame(const frame& frame) const;
761 
762   // Typing
763   virtual bool is_upcall_stub() const override { return true; }
764 
765   // GC/Verification support
766   void oops_do(OopClosure* f, const frame& frame);
767   virtual void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f) override;
768   virtual void verify() override;
769 
770   // Misc.
771   virtual void print_on(outputStream* st) const override;
772   virtual void print_value_on(outputStream* st) const override;
773 };
774 
775 #endif // SHARE_CODE_CODEBLOB_HPP