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.
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 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/checkedCast.hpp"
 34 #include "utilities/growableArray.hpp"
 35 #include "utilities/macros.hpp"
 36 #ifdef ZERO
 37 # include "stack_zero.hpp"
 38 #endif
 39 
 40 typedef class BytecodeInterpreter* interpreterState;
 41 
 42 class CodeBlob;
 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   const ImmutableOopMap* get_oop_map() const;
 93 
 94  public:
 95   // Constructors
 96   frame();
 97 
 98   explicit frame(bool dummy) {} // no initialization
 99 
100   explicit frame(intptr_t* sp);
101 
102 #ifndef PRODUCT
103   // This is a generic constructor which is only used by pns() in debug.cpp.
104   // pns (i.e. print native stack) uses this constructor to create a starting
105   // frame for stack walking. The implementation of this constructor is platform
106   // dependent (i.e. SPARC doesn't need an 'fp' argument an will ignore it) but
107   // we want to keep the signature generic because pns() is shared code.
108   frame(void* sp, void* fp, void* pc);
109 #endif
110 
111   // Accessors
112 
113   // pc: Returns the pc at which this frame will continue normally.
114   // It must point at the beginning of the next instruction to execute.
115   address pc() const             { return _pc; }
116 
117   // This returns the pc that if you were in the debugger you'd see. Not
118   // the idealized value in the frame object. This undoes the magic conversion
119   // that happens for deoptimized frames. In addition it makes the value the
120   // hardware would want to see in the native frame. The only user (at this point)
121   // is deoptimization. It likely no one else should ever use it.
122   address raw_pc() const;
123 
124   // Return the original PC for the given PC if:
125   // (a) the given PC belongs to an nmethod and
126   // (b) it is a deopt PC
127   address get_deopt_original_pc() const;
128 
129   void set_pc(address newpc);
130 
131   intptr_t* sp() const           { assert_absolute(); return _sp; }
132   void set_sp( intptr_t* newsp ) { _sp = newsp; }
133 
134   int offset_sp() const           { assert_offset();  return _offset_sp; }
135   void set_offset_sp( int newsp ) { assert_on_heap(); _offset_sp = newsp; }
136 
137   int frame_index() const {
138   #ifdef ASSERT
139     return _frame_index;
140   #else
141     return -1;
142   #endif
143   }
144   void set_frame_index( int index ) {
145     #ifdef ASSERT
146       _frame_index = index;
147     #endif
148   }
149 
150   static int sender_sp_ret_address_offset();
151 
152   CodeBlob* cb() const           { return _cb; }
153   inline CodeBlob* get_cb() const;
154   // inline void set_cb(CodeBlob* cb);
155 
156   const ImmutableOopMap* oop_map() const {
157     if (_oop_map == nullptr) {
158       _oop_map = get_oop_map();
159     }
160     return _oop_map;
161   }
162 
163   // patching operations
164   void   patch_pc(Thread* thread, address pc);
165 
166   // Every frame needs to return a unique id which distinguishes it from all other frames.
167   // For sparc and ia32 use sp.
168   // No real frame should have an id() of null so it is a distinguishing value for an unmatchable frame.
169   // We also have relationals which allow comparing a frame to another frame's id() allowing
170   // us to distinguish younger (more recent activation) from older (less recent activations)
171   // A null id is only valid when comparing for equality.
172 
173   intptr_t* id(void) const;
174   bool is_younger(intptr_t* id) const;
175   bool is_older(intptr_t* id) const;
176 
177   // testers
178 
179   // Compares for strict equality. Rarely used or needed.
180   // It can return a different result than f1.id() == f2.id()
181   bool equal(frame other) const;
182 
183   // type testers
184   bool is_empty()                const { return _pc == nullptr; }
185   bool is_interpreted_frame()    const;
186   bool is_java_frame()           const;
187   bool is_entry_frame()          const;             // Java frame called from C?
188   bool is_stub_frame()           const;
189   bool is_ignored_frame()        const;
190   bool is_native_frame()         const;
191   bool is_runtime_frame()        const;
192   bool is_compiled_frame()       const;
193   bool is_safepoint_blob_frame() const;
194   bool is_deoptimized_frame()    const;
195   bool is_upcall_stub_frame()    const;
196   bool is_heap_frame()             const { return _on_heap; }
197 
198   // testers
199   bool is_first_frame() const; // oldest frame? (has no sender)
200   bool is_first_java_frame() const;              // same for Java frame
201   bool is_first_vthread_frame(JavaThread* thread) const;
202 
203   bool is_interpreted_frame_valid(JavaThread* thread) const;       // performs sanity checks on interpreted frames.
204 
205   // is this frame doing a call using the compiled calling convention?
206   bool is_compiled_caller() const {
207     return is_compiled_frame() || is_upcall_stub_frame();
208   }
209 
210   // tells whether this frame is marked for deoptimization
211   bool should_be_deoptimized() const;
212 
213   // tells whether this frame can be deoptimized
214   bool can_be_deoptimized() const;
215 
216   // the frame size in machine words
217   inline int frame_size() const;
218 
219   // the size, in words, of stack-passed arguments
220   inline int compiled_frame_stack_argsize() const;
221 
222   inline void interpreted_frame_oop_map(InterpreterOopMap* mask) const;
223 
224   // returns the sending frame
225   inline frame sender(RegisterMap* map) const;
226 
227   bool safe_for_sender(JavaThread *thread);
228 
229   // returns the sender, but skips conversion frames
230   frame real_sender(RegisterMap* map) const;
231 
232   // returns the sending Java frame, skipping any intermediate C frames
233   // NB: receiver must not be first frame
234   frame java_sender() const;
235 
236  private:
237   // Helper methods for better factored code in frame::sender
238   inline frame sender_for_compiled_frame(RegisterMap* map) const;
239   frame sender_for_entry_frame(RegisterMap* map) const;
240   frame sender_for_interpreter_frame(RegisterMap* map) const;
241   frame sender_for_upcall_stub_frame(RegisterMap* map) const;
242 
243   bool is_entry_frame_valid(JavaThread* thread) const;
244 
245   Method* safe_interpreter_frame_method() const;
246 
247   // All frames:
248 
249   // A low-level interface for vframes:
250 
251  public:
252 
253   intptr_t* addr_at(int index) const             { return &fp()[index];    }
254   intptr_t  at_absolute(int index) const         { return *addr_at(index); }
255   // Interpreter frames in continuation stacks are on the heap, and internal addresses are relative to fp.
256   intptr_t  at_relative(int index) const         { return (intptr_t)(fp() + fp()[index]); }
257 
258   intptr_t  at_relative_or_null(int index) const {
259     return (fp()[index] != 0)
260       ? (intptr_t)(fp() + fp()[index])
261       : 0;
262   }
263 
264   intptr_t at(int index) const                   {
265     return _on_heap ? at_relative(index) : at_absolute(index);
266   }
267 
268  public:
269   // Link (i.e., the pointer to the previous frame)
270   // might crash if the frame has no parent
271   intptr_t* link() const;
272 
273   // Link (i.e., the pointer to the previous frame) or null if the link cannot be accessed
274   intptr_t* link_or_null() const;
275 
276   // Return address
277   address  sender_pc() const;
278 
279   // Support for deoptimization
280   void deoptimize(JavaThread* thread);
281 
282   // The frame's original SP, before any extension by an interpreted callee;
283   // used for packing debug info into vframeArray objects and vframeArray lookup.
284   intptr_t* unextended_sp() const;
285   void set_unextended_sp(intptr_t* value);
286 
287   int offset_unextended_sp() const;
288   void set_offset_unextended_sp(int value);
289 
290   // returns the stack pointer of the calling frame
291   intptr_t* sender_sp() const;
292 
293   // Returns the real 'frame pointer' for the current frame.
294   // This is the value expected by the platform ABI when it defines a
295   // frame pointer register. It may differ from the effective value of
296   // the FP register when that register is used in the JVM for other
297   // purposes (like compiled frames on some platforms).
298   // On other platforms, it is defined so that the stack area used by
299   // this frame goes from real_fp() to sp().
300   intptr_t* real_fp() const;
301 
302   // Deoptimization info, if needed (platform dependent).
303   // Stored in the initial_info field of the unroll info, to be used by
304   // the platform dependent deoptimization blobs.
305   intptr_t *initial_deoptimization_info();
306 
307   // Interpreter frames:
308 
309  private:
310   intptr_t* interpreter_frame_locals() const;
311   intptr_t* interpreter_frame_bcp_addr() const;
312   intptr_t* interpreter_frame_mdp_addr() const;
313 
314  public:
315   // Locals
316 
317   // The _at version returns a pointer because the address is used for GC.
318   intptr_t* interpreter_frame_local_at(int index) const;
319 
320   void interpreter_frame_set_locals(intptr_t* locs);
321 
322   // byte code index
323   jint interpreter_frame_bci() const;
324 
325   // byte code pointer
326   address interpreter_frame_bcp() const;
327   void    interpreter_frame_set_bcp(address bcp);
328 
329   // method data pointer
330   address interpreter_frame_mdp() const;
331   void    interpreter_frame_set_mdp(address dp);
332 
333   // Find receiver out of caller's (compiled) argument list
334   oop retrieve_receiver(RegisterMap *reg_map);
335 
336   // Return the monitor owner and BasicLock for compiled synchronized
337   // native methods. Used by JVMTI's GetLocalInstance method
338   // (via VM_GetReceiver) to retrieve the receiver from a native wrapper frame.
339   BasicLock* get_native_monitor() const;
340   oop        get_native_receiver() const;
341 
342   // Find receiver for an invoke when arguments are just pushed on stack (i.e., callee stack-frame is
343   // not setup)
344   oop interpreter_callee_receiver(Symbol* signature);
345 
346 
347   oop* interpreter_callee_receiver_addr(Symbol* signature);
348 
349 
350   // expression stack (may go up or down, direction == 1 or -1)
351  public:
352   intptr_t* interpreter_frame_expression_stack() const;
353 
354   // The _at version returns a pointer because the address is used for GC.
355   intptr_t* interpreter_frame_expression_stack_at(jint offset) const;
356 
357   // top of expression stack
358   intptr_t* interpreter_frame_tos_at(jint offset) const;
359   intptr_t* interpreter_frame_tos_address() const;
360 
361 
362   jint  interpreter_frame_expression_stack_size() const;
363 
364   intptr_t* interpreter_frame_sender_sp() const;
365 
366   // template based interpreter deoptimization support
367   void  set_interpreter_frame_sender_sp(intptr_t* sender_sp);
368   void interpreter_frame_set_monitor_end(BasicObjectLock* value);
369 
370   // Address of the temp oop in the frame. Needed as GC root.
371   oop* interpreter_frame_temp_oop_addr() const;
372 
373   // BasicObjectLocks:
374   //
375   // interpreter_frame_monitor_begin is higher in memory than interpreter_frame_monitor_end
376   // Interpreter_frame_monitor_begin points to one element beyond the oldest one,
377   // interpreter_frame_monitor_end   points to the youngest one, or if there are none,
378   //                                 it points to one beyond where the first element will be.
379   // interpreter_frame_monitor_size  reports the allocation size of a monitor in the interpreter stack.
380   //                                 this value is >= BasicObjectLock::size(), and may be rounded up
381 
382   BasicObjectLock* interpreter_frame_monitor_begin() const;
383   BasicObjectLock* interpreter_frame_monitor_end()   const;
384   BasicObjectLock* next_monitor_in_interpreter_frame(BasicObjectLock* current) const;
385   BasicObjectLock* previous_monitor_in_interpreter_frame(BasicObjectLock* current) const;
386   static int interpreter_frame_monitor_size();
387   static int interpreter_frame_monitor_size_in_bytes();
388 
389 #ifdef ASSERT
390   void interpreter_frame_verify_monitor(BasicObjectLock* value) const;
391 #endif
392 
393   // Return/result value from this interpreter frame
394   // If the method return type is T_OBJECT or T_ARRAY populates oop_result
395   // For other (non-T_VOID) the appropriate field in the jvalue is populated
396   // with the result value.
397   // Should only be called when at method exit when the method is not
398   // exiting due to an exception.
399   BasicType interpreter_frame_result(oop* oop_result, jvalue* value_result);
400 
401  public:
402   // Method & constant pool cache
403   Method* interpreter_frame_method() const;
404   void interpreter_frame_set_method(Method* method);
405   Method** interpreter_frame_method_addr() const;
406   ConstantPoolCache** interpreter_frame_cache_addr() const;
407   oop* interpreter_frame_mirror_addr() const;
408 
409   void interpreter_frame_set_mirror(oop mirror);
410 
411  public:
412   // Entry frames
413   JavaCallWrapper* entry_frame_call_wrapper() const { return *entry_frame_call_wrapper_addr(); }
414   JavaCallWrapper* entry_frame_call_wrapper_if_safe(JavaThread* thread) const;
415   JavaCallWrapper** entry_frame_call_wrapper_addr() const;
416   intptr_t* entry_frame_argument_at(int offset) const;
417 
418   // tells whether there is another chunk of Delta stack above
419   bool entry_frame_is_first() const;
420   bool upcall_stub_frame_is_first() const;
421 
422   // Safepoints
423 
424  public:
425   oop saved_oop_result(RegisterMap* map) const;
426   void set_saved_oop_result(RegisterMap* map, oop obj);
427 
428   static JavaThread** saved_thread_address(const frame& f);
429 
430   // For debugging
431  private:
432   const char* print_name() const;
433 
434   void describe_pd(FrameValues& values, int frame_no);
435 
436  public:
437   void print_value() const { print_value_on(tty); }
438   void print_value_on(outputStream* st) const;
439   void print_on(outputStream* st) const;
440   void interpreter_frame_print_on(outputStream* st) const;
441   void print_on_error(outputStream* st, char* buf, int buflen, bool verbose = false) const;
442   static void print_C_frame(outputStream* st, char* buf, int buflen, address pc);
443   static frame next_frame(frame fr, Thread* t); // For native stack walking
444 
445 #ifndef PRODUCT
446   // Add annotated descriptions of memory locations belonging to this frame to values
447   void describe(FrameValues& values, int frame_no, const RegisterMap* reg_map=nullptr, bool top = false);
448 #endif
449 
450   // Conversion from a VMReg to physical stack location
451   template <typename RegisterMapT>
452   address oopmapreg_to_location(VMReg reg, const RegisterMapT* reg_map) const;
453   template <typename RegisterMapT>
454   oop* oopmapreg_to_oop_location(VMReg reg, const RegisterMapT* reg_map) const;
455 
456   // Oops-do's
457   void oops_compiled_arguments_do(Symbol* signature, bool has_receiver, bool has_appendix, const RegisterMap* reg_map, OopClosure* f) const;
458   void oops_interpreted_do(OopClosure* f, const RegisterMap* map, bool query_oop_map_cache = true) const;
459   void buffered_values_interpreted_do(BufferedValueClosure* f);
460 
461  private:
462   void oops_interpreted_arguments_do(Symbol* signature, bool has_receiver, OopClosure* f) const;
463 
464   // Iteration of oops
465   void oops_do_internal(OopClosure* f, NMethodClosure* cf,
466                         DerivedOopClosure* df, DerivedPointerIterationMode derived_mode,
467                         const RegisterMap* map, bool use_interpreter_oop_map_cache) const;
468 
469   void oops_entry_do(OopClosure* f, const RegisterMap* map) const;
470   void oops_upcall_do(OopClosure* f, const RegisterMap* map) const;
471   void oops_nmethod_do(OopClosure* f, NMethodClosure* cf,
472                        DerivedOopClosure* df, DerivedPointerIterationMode derived_mode,
473                        const RegisterMap* map) const;
474  public:
475   // Memory management
476   void oops_do(OopClosure* f, NMethodClosure* cf, const RegisterMap* map) {
477 #if COMPILER2_OR_JVMCI
478     DerivedPointerIterationMode dpim = DerivedPointerTable::is_active() ?
479                                        DerivedPointerIterationMode::_with_table :
480                                        DerivedPointerIterationMode::_ignore;
481 #else
482     DerivedPointerIterationMode dpim = DerivedPointerIterationMode::_ignore;;
483 #endif
484     oops_do_internal(f, cf, nullptr, dpim, map, true);
485   }
486 
487   void oops_do(OopClosure* f, NMethodClosure* cf, DerivedOopClosure* df, const RegisterMap* map) {
488     oops_do_internal(f, cf, df, DerivedPointerIterationMode::_ignore, map, true);
489   }
490 
491   void oops_do(OopClosure* f, NMethodClosure* cf, const RegisterMap* map,
492                DerivedPointerIterationMode derived_mode) const {
493     oops_do_internal(f, cf, nullptr, derived_mode, map, true);
494   }
495 
496   void nmethod_do(NMethodClosure* cf) const;
497 
498   // RedefineClasses support for finding live interpreted methods on the stack
499   void metadata_do(MetadataClosure* f) const;
500 
501   // Verification
502   void verify(const RegisterMap* map) const;
503 #ifdef ASSERT
504   static bool verify_return_pc(address x);
505   // Usage:
506   // assert(frame::verify_return_pc(return_address), "must be a return pc");
507 #endif
508 
509 #include CPU_HEADER(frame)
510 
511 };
512 
513 #ifndef PRODUCT
514 // A simple class to describe a location on the stack
515 class FrameValue {
516  public:
517   intptr_t* location;
518   char* description;
519   int owner;
520   int priority;
521 
522   FrameValue() {
523     location = nullptr;
524     description = nullptr;
525     owner = -1;
526     priority = 0;
527   }
528 };
529 
530 
531 // A collection of described stack values that can print a symbolic
532 // description of the stack memory.  Interpreter frame values can be
533 // in the caller frames so all the values are collected first and then
534 // sorted before being printed.
535 class FrameValues {
536  private:
537   GrowableArray<FrameValue> _values;
538 
539   static int compare(FrameValue* a, FrameValue* b) {
540     if (a->location == b->location) {
541       return a->priority - b->priority;
542     }
543     return checked_cast<int>(a->location - b->location);
544   }
545 
546   void print_on(outputStream* out, int min_index, int max_index, intptr_t* v0, intptr_t* v1);
547 
548  public:
549   // Used by frame functions to describe locations.
550   void describe(int owner, intptr_t* location, const char* description, int priority = 0);
551 
552 #ifdef ASSERT
553   void validate();
554 #endif
555   void print(JavaThread* thread) { print_on(thread, tty); }
556   void print_on(JavaThread* thread, outputStream* out);
557   void print(stackChunkOop chunk) { print_on(chunk, tty); }
558   void print_on(stackChunkOop chunk, outputStream* out);
559 };
560 
561 #endif
562 
563 
564 #endif // SHARE_RUNTIME_FRAME_HPP