1 /*
  2  * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
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 23  */
 24 
 25 #ifndef SHARE_RUNTIME_FRAME_HPP
 26 #define SHARE_RUNTIME_FRAME_HPP
 27 
 28 #include "code/vmregTypes.hpp"
 29 #include "compiler/oopMap.hpp"
 30 #include "oops/oopsHierarchy.hpp"
 31 #include "runtime/basicLock.hpp"
 32 #include "runtime/monitorChunk.hpp"
 33 #include "utilities/growableArray.hpp"
 34 #include "utilities/macros.hpp"
 35 #ifdef ZERO
 36 # include "stack_zero.hpp"
 37 #endif
 38 
 39 typedef class BytecodeInterpreter* interpreterState;
 40 
 41 class CodeBlob;
 42 class CompiledMethod;
 43 class FrameValues;
 44 class InterpreterOopMap;
 45 class JavaCallWrapper;
 46 class Method;
 47 class methodHandle;
 48 class RegisterMap;
 49 class vframeArray;
 50 
 51 enum class DerivedPointerIterationMode {
 52   _with_table,
 53   _directly,
 54   _ignore
 55 };
 56 
 57 // A frame represents a physical stack frame (an activation).  Frames
 58 // can be C or Java frames, and the Java frames can be interpreted or
 59 // compiled.  In contrast, vframes represent source-level activations,
 60 // so that one physical frame can correspond to multiple source level
 61 // frames because of inlining.
 62 
 63 class frame {
 64  private:
 65   // Instance variables:
 66   union {
 67     intptr_t* _sp; // stack pointer (from Thread::last_Java_sp)
 68     int _offset_sp; // used by frames in stack chunks
 69   };
 70   address   _pc; // program counter (the next instruction after the call)
 71   mutable CodeBlob* _cb; // CodeBlob that "owns" pc
 72   mutable const ImmutableOopMap* _oop_map; // oop map, for compiled/stubs frames only
 73   enum deopt_state {
 74     not_deoptimized,
 75     is_deoptimized,
 76     unknown
 77   };
 78 
 79   deopt_state _deopt_state;
 80 
 81   // Do internal pointers in interpreter frames use absolute adddresses or relative (to fp)?
 82   // Frames in stack chunks are on the Java heap and use relative addressing; on the stack
 83   // they use absolute addressing
 84   bool        _on_heap;  // This frame represents a frame on the heap.
 85   DEBUG_ONLY(int _frame_index;) // the frame index in a stack chunk; -1 when on a thread stack
 86 
 87   // We use different assertions to allow for intermediate states (e.g. during thawing or relativizing the frame)
 88   void assert_on_heap() const  { assert(is_heap_frame(), "Using offset with a non-chunk frame"); }
 89   void assert_offset() const   { assert(_frame_index >= 0,  "Using offset with a non-chunk frame"); assert_on_heap(); }
 90   void assert_absolute() const { assert(_frame_index == -1, "Using absolute addresses with a chunk frame"); }
 91 
 92  public:
 93   // Constructors
 94   frame();
 95 
 96   explicit frame(bool dummy) {} // no initialization
 97 
 98   explicit frame(intptr_t* sp);
 99 
100 #ifndef PRODUCT
101   // This is a generic constructor which is only used by pns() in debug.cpp.
102   // pns (i.e. print native stack) uses this constructor to create a starting
103   // frame for stack walking. The implementation of this constructor is platform
104   // dependent (i.e. SPARC doesn't need an 'fp' argument an will ignore it) but
105   // we want to keep the signature generic because pns() is shared code.
106   frame(void* sp, void* fp, void* pc);
107 #endif
108 
109   // Accessors
110 
111   // pc: Returns the pc at which this frame will continue normally.
112   // It must point at the beginning of the next instruction to execute.
113   address pc() const             { return _pc; }
114 
115   // This returns the pc that if you were in the debugger you'd see. Not
116   // the idealized value in the frame object. This undoes the magic conversion
117   // that happens for deoptimized frames. In addition it makes the value the
118   // hardware would want to see in the native frame. The only user (at this point)
119   // is deoptimization. It likely no one else should ever use it.
120   address raw_pc() const;
121 
122   void set_pc(address newpc);
123 
124   intptr_t* sp() const           { assert_absolute(); return _sp; }
125   void set_sp( intptr_t* newsp ) { _sp = newsp; }
126 
127   int offset_sp() const           { assert_offset();  return _offset_sp; }
128   void set_offset_sp( int newsp ) { assert_on_heap(); _offset_sp = newsp; }
129 
130   int frame_index() const {
131   #ifdef ASSERT
132     return _frame_index;
133   #else
134     return -1;
135   #endif
136   }
137   void set_frame_index( int index ) {
138     #ifdef ASSERT
139       _frame_index = index;
140     #endif
141   }
142 
143   static int sender_sp_ret_address_offset();
144 
145   CodeBlob* cb() const           { return _cb; }
146   inline CodeBlob* get_cb() const;
147   // inline void set_cb(CodeBlob* cb);
148 
149   const ImmutableOopMap* oop_map() const {
150     if (_oop_map == nullptr) {
151       _oop_map = get_oop_map();
152     }
153     return _oop_map;
154   }
155 
156   // patching operations
157   void   patch_pc(Thread* thread, address pc);
158 
159   // Every frame needs to return a unique id which distinguishes it from all other frames.
160   // For sparc and ia32 use sp. ia64 can have memory frames that are empty so multiple frames
161   // will have identical sp values. For ia64 the bsp (fp) value will serve. No real frame
162   // should have an id() of null so it is a distinguishing value for an unmatchable frame.
163   // We also have relationals which allow comparing a frame to anoth frame's id() allow
164   // us to distinguish younger (more recent activation) from older (less recent activations)
165   // A null id is only valid when comparing for equality.
166 
167   intptr_t* id(void) const;
168   bool is_younger(intptr_t* id) const;
169   bool is_older(intptr_t* id) const;
170 
171   // testers
172 
173   // Compares for strict equality. Rarely used or needed.
174   // It can return a different result than f1.id() == f2.id()
175   bool equal(frame other) const;
176 
177   // type testers
178   bool is_empty()                const { return _pc == nullptr; }
179   bool is_interpreted_frame()    const;
180   bool is_java_frame()           const;
181   bool is_entry_frame()          const;             // Java frame called from C?
182   bool is_stub_frame()           const;
183   bool is_ignored_frame()        const;
184   bool is_native_frame()         const;
185   bool is_runtime_frame()        const;
186   bool is_compiled_frame()       const;
187   bool is_safepoint_blob_frame() const;
188   bool is_deoptimized_frame()    const;
189   bool is_upcall_stub_frame()    const;
190   bool is_heap_frame()             const { return _on_heap; }
191 
192   // testers
193   bool is_first_frame() const; // oldest frame? (has no sender)
194   bool is_first_java_frame() const;              // same for Java frame
195   bool is_first_vthread_frame(JavaThread* thread) const;
196 
197   bool is_interpreted_frame_valid(JavaThread* thread) const;       // performs sanity checks on interpreted frames.
198 
199   // is this frame doing a call using the compiled calling convention?
200   bool is_compiled_caller() const {
201     return is_compiled_frame() || is_upcall_stub_frame();
202   }
203 
204   // tells whether this frame is marked for deoptimization
205   bool should_be_deoptimized() const;
206 
207   // tells whether this frame can be deoptimized
208   bool can_be_deoptimized() const;
209 
210   // the frame size in machine words
211   inline int frame_size() const;
212 
213   // the size, in words, of stack-passed arguments
214   inline int compiled_frame_stack_argsize() const;
215 
216   inline void interpreted_frame_oop_map(InterpreterOopMap* mask) const;
217 
218   // returns the sending frame
219   inline frame sender(RegisterMap* map) const;
220 
221   bool safe_for_sender(JavaThread *thread);
222 
223   // returns the sender, but skips conversion frames
224   frame real_sender(RegisterMap* map) const;
225 
226   // returns the sending Java frame, skipping any intermediate C frames
227   // NB: receiver must not be first frame
228   frame java_sender() const;
229 
230  private:
231   // Helper methods for better factored code in frame::sender
232   inline frame sender_for_compiled_frame(RegisterMap* map) const;
233   frame sender_for_entry_frame(RegisterMap* map) const;
234   frame sender_for_interpreter_frame(RegisterMap* map) const;
235   frame sender_for_upcall_stub_frame(RegisterMap* map) const;
236 
237   bool is_entry_frame_valid(JavaThread* thread) const;
238 
239   // All frames:
240 
241   // A low-level interface for vframes:
242 
243  public:
244 
245   intptr_t* addr_at(int index) const             { return &fp()[index];    }
246   intptr_t  at_absolute(int index) const         { return *addr_at(index); }
247   // Interpreter frames in continuation stacks are on the heap, and internal addresses are relative to fp.
248   intptr_t  at_relative(int index) const         { return (intptr_t)(fp() + fp()[index]); }
249 
250   intptr_t at(int index) const                   {
251     return _on_heap ? at_relative(index) : at_absolute(index);
252   }
253 
254  public:
255   // Link (i.e., the pointer to the previous frame)
256   // might crash if the frame has no parent
257   intptr_t* link() const;
258 
259   // Link (i.e., the pointer to the previous frame) or null if the link cannot be accessed
260   intptr_t* link_or_null() const;
261 
262   // Return address
263   address  sender_pc() const;
264 
265   // Support for deoptimization
266   void deoptimize(JavaThread* thread);
267 
268   // The frame's original SP, before any extension by an interpreted callee;
269   // used for packing debug info into vframeArray objects and vframeArray lookup.
270   intptr_t* unextended_sp() const;
271   void set_unextended_sp(intptr_t* value);
272 
273   int offset_unextended_sp() const;
274   void set_offset_unextended_sp(int value);
275 
276   // returns the stack pointer of the calling frame
277   intptr_t* sender_sp() const;
278 
279   // Returns the real 'frame pointer' for the current frame.
280   // This is the value expected by the platform ABI when it defines a
281   // frame pointer register. It may differ from the effective value of
282   // the FP register when that register is used in the JVM for other
283   // purposes (like compiled frames on some platforms).
284   // On other platforms, it is defined so that the stack area used by
285   // this frame goes from real_fp() to sp().
286   intptr_t* real_fp() const;
287 
288   // Deoptimization info, if needed (platform dependent).
289   // Stored in the initial_info field of the unroll info, to be used by
290   // the platform dependent deoptimization blobs.
291   intptr_t *initial_deoptimization_info();
292 
293   // Interpreter frames:
294 
295  private:
296   intptr_t* interpreter_frame_locals() const;
297   intptr_t* interpreter_frame_bcp_addr() const;
298   intptr_t* interpreter_frame_mdp_addr() const;
299 
300  public:
301   // Locals
302 
303   // The _at version returns a pointer because the address is used for GC.
304   intptr_t* interpreter_frame_local_at(int index) const;
305 
306   void interpreter_frame_set_locals(intptr_t* locs);
307 
308   // byte code index
309   jint interpreter_frame_bci() const;
310 
311   // byte code pointer
312   address interpreter_frame_bcp() const;
313   void    interpreter_frame_set_bcp(address bcp);
314 
315   // method data pointer
316   address interpreter_frame_mdp() const;
317   void    interpreter_frame_set_mdp(address dp);
318 
319   // Find receiver out of caller's (compiled) argument list
320   oop retrieve_receiver(RegisterMap *reg_map);
321 
322   // Return the monitor owner and BasicLock for compiled synchronized
323   // native methods. Used by JVMTI's GetLocalInstance method
324   // (via VM_GetReceiver) to retrieve the receiver from a native wrapper frame.
325   BasicLock* get_native_monitor();
326   oop        get_native_receiver();
327 
328   // Find receiver for an invoke when arguments are just pushed on stack (i.e., callee stack-frame is
329   // not setup)
330   oop interpreter_callee_receiver(Symbol* signature);
331 
332 
333   oop* interpreter_callee_receiver_addr(Symbol* signature);
334 
335 
336   // expression stack (may go up or down, direction == 1 or -1)
337  public:
338   intptr_t* interpreter_frame_expression_stack() const;
339 
340   // The _at version returns a pointer because the address is used for GC.
341   intptr_t* interpreter_frame_expression_stack_at(jint offset) const;
342 
343   // top of expression stack
344   intptr_t* interpreter_frame_tos_at(jint offset) const;
345   intptr_t* interpreter_frame_tos_address() const;
346 
347 
348   jint  interpreter_frame_expression_stack_size() const;
349 
350   intptr_t* interpreter_frame_sender_sp() const;
351 
352   // template based interpreter deoptimization support
353   void  set_interpreter_frame_sender_sp(intptr_t* sender_sp);
354   void interpreter_frame_set_monitor_end(BasicObjectLock* value);
355 
356   // Address of the temp oop in the frame. Needed as GC root.
357   oop* interpreter_frame_temp_oop_addr() const;
358 
359   // BasicObjectLocks:
360   //
361   // interpreter_frame_monitor_begin is higher in memory than interpreter_frame_monitor_end
362   // Interpreter_frame_monitor_begin points to one element beyond the oldest one,
363   // interpreter_frame_monitor_end   points to the youngest one, or if there are none,
364   //                                 it points to one beyond where the first element will be.
365   // interpreter_frame_monitor_size  reports the allocation size of a monitor in the interpreter stack.
366   //                                 this value is >= BasicObjectLock::size(), and may be rounded up
367 
368   BasicObjectLock* interpreter_frame_monitor_begin() const;
369   BasicObjectLock* interpreter_frame_monitor_end()   const;
370   BasicObjectLock* next_monitor_in_interpreter_frame(BasicObjectLock* current) const;
371   BasicObjectLock* previous_monitor_in_interpreter_frame(BasicObjectLock* current) const;
372   static int interpreter_frame_monitor_size();
373 
374   void interpreter_frame_verify_monitor(BasicObjectLock* value) const;
375 
376   // Return/result value from this interpreter frame
377   // If the method return type is T_OBJECT or T_ARRAY populates oop_result
378   // For other (non-T_VOID) the appropriate field in the jvalue is populated
379   // with the result value.
380   // Should only be called when at method exit when the method is not
381   // exiting due to an exception.
382   BasicType interpreter_frame_result(oop* oop_result, jvalue* value_result);
383 
384  public:
385   // Method & constant pool cache
386   Method* interpreter_frame_method() const;
387   void interpreter_frame_set_method(Method* method);
388   Method** interpreter_frame_method_addr() const;
389   ConstantPoolCache** interpreter_frame_cache_addr() const;
390   oop* interpreter_frame_mirror_addr() const;
391 
392   void interpreter_frame_set_mirror(oop mirror);
393 
394  public:
395   // Entry frames
396   JavaCallWrapper* entry_frame_call_wrapper() const { return *entry_frame_call_wrapper_addr(); }
397   JavaCallWrapper* entry_frame_call_wrapper_if_safe(JavaThread* thread) const;
398   JavaCallWrapper** entry_frame_call_wrapper_addr() const;
399   intptr_t* entry_frame_argument_at(int offset) const;
400 
401   // tells whether there is another chunk of Delta stack above
402   bool entry_frame_is_first() const;
403   bool upcall_stub_frame_is_first() const;
404 
405   // Safepoints
406 
407  public:
408   oop saved_oop_result(RegisterMap* map) const;
409   void set_saved_oop_result(RegisterMap* map, oop obj);
410 
411   // For debugging
412  private:
413   const char* print_name() const;
414 
415   void describe_pd(FrameValues& values, int frame_no);
416 
417  public:
418   void print_value() const { print_value_on(tty,nullptr); }
419   void print_value_on(outputStream* st, JavaThread *thread) const;
420   void print_on(outputStream* st) const;
421   void interpreter_frame_print_on(outputStream* st) const;
422   void print_on_error(outputStream* st, char* buf, int buflen, bool verbose = false) const;
423   static void print_C_frame(outputStream* st, char* buf, int buflen, address pc);
424 
425   // Add annotated descriptions of memory locations belonging to this frame to values
426   void describe(FrameValues& values, int frame_no, const RegisterMap* reg_map=nullptr);
427 
428   // Conversion from a VMReg to physical stack location
429   template <typename RegisterMapT>
430   address oopmapreg_to_location(VMReg reg, const RegisterMapT* reg_map) const;
431   template <typename RegisterMapT>
432   oop* oopmapreg_to_oop_location(VMReg reg, const RegisterMapT* reg_map) const;
433 
434   // Oops-do's
435   void oops_compiled_arguments_do(Symbol* signature, bool has_receiver, bool has_appendix, const RegisterMap* reg_map, OopClosure* f) const;
436   void oops_interpreted_do(OopClosure* f, const RegisterMap* map, bool query_oop_map_cache = true) const;
437   void buffered_values_interpreted_do(BufferedValueClosure* f);
438 
439  private:
440   void oops_interpreted_arguments_do(Symbol* signature, bool has_receiver, OopClosure* f) const;
441 
442   // Iteration of oops
443   void oops_do_internal(OopClosure* f, CodeBlobClosure* cf,
444                         DerivedOopClosure* df, DerivedPointerIterationMode derived_mode,
445                         const RegisterMap* map, bool use_interpreter_oop_map_cache) const;
446 
447   void oops_entry_do(OopClosure* f, const RegisterMap* map) const;
448   void oops_code_blob_do(OopClosure* f, CodeBlobClosure* cf,
449                          DerivedOopClosure* df, DerivedPointerIterationMode derived_mode,
450                          const RegisterMap* map) const;
451  public:
452   // Memory management
453   void oops_do(OopClosure* f, CodeBlobClosure* cf, const RegisterMap* map) {
454 #if COMPILER2_OR_JVMCI
455     DerivedPointerIterationMode dpim = DerivedPointerTable::is_active() ?
456                                        DerivedPointerIterationMode::_with_table :
457                                        DerivedPointerIterationMode::_ignore;
458 #else
459     DerivedPointerIterationMode dpim = DerivedPointerIterationMode::_ignore;;
460 #endif
461     oops_do_internal(f, cf, nullptr, dpim, map, true);
462   }
463 
464   void oops_do(OopClosure* f, CodeBlobClosure* cf, DerivedOopClosure* df, const RegisterMap* map) {
465     oops_do_internal(f, cf, df, DerivedPointerIterationMode::_ignore, map, true);
466   }
467 
468   void oops_do(OopClosure* f, CodeBlobClosure* cf, const RegisterMap* map,
469                DerivedPointerIterationMode derived_mode) const {
470     oops_do_internal(f, cf, nullptr, derived_mode, map, true);
471   }
472 
473   void nmethods_do(CodeBlobClosure* cf) const;
474 
475   // RedefineClasses support for finding live interpreted methods on the stack
476   void metadata_do(MetadataClosure* f) const;
477 
478   // Verification
479   void verify(const RegisterMap* map) const;
480   static bool verify_return_pc(address x);
481   // Usage:
482   // assert(frame::verify_return_pc(return_address), "must be a return pc");
483 
484 #include CPU_HEADER(frame)
485 
486 };
487 
488 #ifndef PRODUCT
489 // A simple class to describe a location on the stack
490 class FrameValue {
491  public:
492   intptr_t* location;
493   char* description;
494   int owner;
495   int priority;
496 
497   FrameValue() {
498     location = nullptr;
499     description = nullptr;
500     owner = -1;
501     priority = 0;
502   }
503 };
504 
505 
506 // A collection of described stack values that can print a symbolic
507 // description of the stack memory.  Interpreter frame values can be
508 // in the caller frames so all the values are collected first and then
509 // sorted before being printed.
510 class FrameValues {
511  private:
512   GrowableArray<FrameValue> _values;
513 
514   static int compare(FrameValue* a, FrameValue* b) {
515     if (a->location == b->location) {
516       return a->priority - b->priority;
517     }
518     return a->location - b->location;
519   }
520 
521   void print_on(outputStream* out, int min_index, int max_index, intptr_t* v0, intptr_t* v1,
522                 bool on_heap = false);
523 
524  public:
525   // Used by frame functions to describe locations.
526   void describe(int owner, intptr_t* location, const char* description, int priority = 0);
527 
528 #ifdef ASSERT
529   void validate();
530 #endif
531   void print(JavaThread* thread) { print_on(thread, tty); }
532   void print_on(JavaThread* thread, outputStream* out);
533   void print(stackChunkOop chunk) { print_on(chunk, tty); }
534   void print_on(stackChunkOop chunk, outputStream* out);
535 };
536 
537 #endif
538 
539 
540 #endif // SHARE_RUNTIME_FRAME_HPP