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
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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 CompiledMethod;
 44 class FrameValues;
 45 class InterpreterOopMap;
 46 class JavaCallWrapper;
 47 class Method;
 48 class methodHandle;
 49 class RegisterMap;
 50 class vframeArray;
 51 
 52 enum class DerivedPointerIterationMode {
 53   _with_table,
 54   _directly,
 55   _ignore
 56 };
 57 
 58 // A frame represents a physical stack frame (an activation).  Frames
 59 // can be C or Java frames, and the Java frames can be interpreted or
 60 // compiled.  In contrast, vframes represent source-level activations,
 61 // so that one physical frame can correspond to multiple source level
 62 // frames because of inlining.
 63 
 64 class frame {
 65  private:
 66   // Instance variables:
 67   union {
 68     intptr_t* _sp; // stack pointer (from Thread::last_Java_sp)
 69     int _offset_sp; // used by frames in stack chunks
 70   };
 71   address   _pc; // program counter (the next instruction after the call)
 72   mutable CodeBlob* _cb; // CodeBlob that "owns" pc
 73   mutable const ImmutableOopMap* _oop_map; // oop map, for compiled/stubs frames only
 74   enum deopt_state {
 75     not_deoptimized,
 76     is_deoptimized,
 77     unknown
 78   };
 79 
 80   deopt_state _deopt_state;
 81 
 82   // Do internal pointers in interpreter frames use absolute adddresses or relative (to fp)?
 83   // Frames in stack chunks are on the Java heap and use relative addressing; on the stack
 84   // they use absolute addressing
 85   bool        _on_heap;  // This frame represents a frame on the heap.
 86   DEBUG_ONLY(int _frame_index;) // the frame index in a stack chunk; -1 when on a thread stack
 87 
 88   // We use different assertions to allow for intermediate states (e.g. during thawing or relativizing the frame)
 89   void assert_on_heap() const  { assert(is_heap_frame(), "Using offset with a non-chunk frame"); }
 90   void assert_offset() const   { assert(_frame_index >= 0,  "Using offset with a non-chunk frame"); assert_on_heap(); }
 91   void assert_absolute() const { assert(_frame_index == -1, "Using absolute addresses with a chunk frame"); }
 92 
 93  public:
 94   // Constructors
 95   frame();
 96 
 97   explicit frame(bool dummy) {} // no initialization
 98 
 99   explicit frame(intptr_t* sp);
100 
101 #ifndef PRODUCT
102   // This is a generic constructor which is only used by pns() in debug.cpp.
103   // pns (i.e. print native stack) uses this constructor to create a starting
104   // frame for stack walking. The implementation of this constructor is platform
105   // dependent (i.e. SPARC doesn't need an 'fp' argument an will ignore it) but
106   // we want to keep the signature generic because pns() is shared code.
107   frame(void* sp, void* fp, void* pc);
108 #endif
109 
110   // Accessors
111 
112   // pc: Returns the pc at which this frame will continue normally.
113   // It must point at the beginning of the next instruction to execute.
114   address pc() const             { return _pc; }
115 
116   // This returns the pc that if you were in the debugger you'd see. Not
117   // the idealized value in the frame object. This undoes the magic conversion
118   // that happens for deoptimized frames. In addition it makes the value the
119   // hardware would want to see in the native frame. The only user (at this point)
120   // is deoptimization. It likely no one else should ever use it.
121   address raw_pc() const;
122 
123   void set_pc(address newpc);
124 
125   intptr_t* sp() const           { assert_absolute(); return _sp; }
126   void set_sp( intptr_t* newsp ) { _sp = newsp; }
127 
128   int offset_sp() const           { assert_offset();  return _offset_sp; }
129   void set_offset_sp( int newsp ) { assert_on_heap(); _offset_sp = newsp; }
130 
131   int frame_index() const {
132   #ifdef ASSERT
133     return _frame_index;
134   #else
135     return -1;
136   #endif
137   }
138   void set_frame_index( int index ) {
139     #ifdef ASSERT
140       _frame_index = index;
141     #endif
142   }
143 
144   static int sender_sp_ret_address_offset();
145 
146   CodeBlob* cb() const           { return _cb; }
147   inline CodeBlob* get_cb() const;
148   // inline void set_cb(CodeBlob* cb);
149 
150   const ImmutableOopMap* oop_map() const {
151     if (_oop_map == nullptr) {
152       _oop_map = get_oop_map();
153     }
154     return _oop_map;
155   }
156 
157   // patching operations
158   void   patch_pc(Thread* thread, address pc);
159 
160   // Every frame needs to return a unique id which distinguishes it from all other frames.
161   // For sparc and ia32 use sp. ia64 can have memory frames that are empty so multiple frames
162   // will have identical sp values. For ia64 the bsp (fp) value will serve. No real frame
163   // should have an id() of null so it is a distinguishing value for an unmatchable frame.
164   // We also have relationals which allow comparing a frame to anoth frame's id() allow
165   // us to distinguish younger (more recent activation) from older (less recent activations)
166   // A null id is only valid when comparing for equality.
167 
168   intptr_t* id(void) const;
169   bool is_younger(intptr_t* id) const;
170   bool is_older(intptr_t* id) const;
171 
172   // testers
173 
174   // Compares for strict equality. Rarely used or needed.
175   // It can return a different result than f1.id() == f2.id()
176   bool equal(frame other) const;
177 
178   // type testers
179   bool is_empty()                const { return _pc == nullptr; }
180   bool is_interpreted_frame()    const;
181   bool is_java_frame()           const;
182   bool is_entry_frame()          const;             // Java frame called from C?
183   bool is_stub_frame()           const;
184   bool is_ignored_frame()        const;
185   bool is_native_frame()         const;
186   bool is_runtime_frame()        const;
187   bool is_compiled_frame()       const;
188   bool is_safepoint_blob_frame() const;
189   bool is_deoptimized_frame()    const;
190   bool is_upcall_stub_frame()    const;
191   bool is_heap_frame()             const { return _on_heap; }
192 
193   // testers
194   bool is_first_frame() const; // oldest frame? (has no sender)
195   bool is_first_java_frame() const;              // same for Java frame
196   bool is_first_vthread_frame(JavaThread* thread) const;
197 
198   bool is_interpreted_frame_valid(JavaThread* thread) const;       // performs sanity checks on interpreted frames.
199 
200   // is this frame doing a call using the compiled calling convention?
201   bool is_compiled_caller() const {
202     return is_compiled_frame() || is_upcall_stub_frame();
203   }
204 
205   // tells whether this frame is marked for deoptimization
206   bool should_be_deoptimized() const;
207 
208   // tells whether this frame can be deoptimized
209   bool can_be_deoptimized() const;
210 
211   // the frame size in machine words
212   inline int frame_size() const;
213 
214   // the size, in words, of stack-passed arguments
215   inline int compiled_frame_stack_argsize() const;
216 
217   inline void interpreted_frame_oop_map(InterpreterOopMap* mask) const;
218 
219   // returns the sending frame
220   inline frame sender(RegisterMap* map) const;
221 
222   bool safe_for_sender(JavaThread *thread);
223 
224   // returns the sender, but skips conversion frames
225   frame real_sender(RegisterMap* map) const;
226 
227   // returns the sending Java frame, skipping any intermediate C frames
228   // NB: receiver must not be first frame
229   frame java_sender() const;
230 
231  private:
232   // Helper methods for better factored code in frame::sender
233   inline frame sender_for_compiled_frame(RegisterMap* map) const;
234   frame sender_for_entry_frame(RegisterMap* map) const;
235   frame sender_for_interpreter_frame(RegisterMap* map) const;
236   frame sender_for_upcall_stub_frame(RegisterMap* map) const;
237 
238   bool is_entry_frame_valid(JavaThread* thread) const;
239 
240   Method* safe_interpreter_frame_method() const;
241 
242   // All frames:
243 
244   // A low-level interface for vframes:
245 
246  public:
247 
248   intptr_t* addr_at(int index) const             { return &fp()[index];    }
249   intptr_t  at_absolute(int index) const         { return *addr_at(index); }
250   // Interpreter frames in continuation stacks are on the heap, and internal addresses are relative to fp.
251   intptr_t  at_relative(int index) const         { return (intptr_t)(fp() + fp()[index]); }
252 
253   intptr_t  at_relative_or_null(int index) const {
254     return (fp()[index] != 0)
255       ? (intptr_t)(fp() + fp()[index])
256       : 0;
257   }
258 
259   intptr_t at(int index) const                   {
260     return _on_heap ? at_relative(index) : at_absolute(index);
261   }
262 
263  public:
264   // Link (i.e., the pointer to the previous frame)
265   // might crash if the frame has no parent
266   intptr_t* link() const;
267 
268   // Link (i.e., the pointer to the previous frame) or null if the link cannot be accessed
269   intptr_t* link_or_null() const;
270 
271   // Return address
272   address  sender_pc() const;
273 
274   // Support for deoptimization
275   void deoptimize(JavaThread* thread);
276 
277   // The frame's original SP, before any extension by an interpreted callee;
278   // used for packing debug info into vframeArray objects and vframeArray lookup.
279   intptr_t* unextended_sp() const;
280   void set_unextended_sp(intptr_t* value);
281 
282   int offset_unextended_sp() const;
283   void set_offset_unextended_sp(int value);
284 
285   // returns the stack pointer of the calling frame
286   intptr_t* sender_sp() const;
287 
288   // Returns the real 'frame pointer' for the current frame.
289   // This is the value expected by the platform ABI when it defines a
290   // frame pointer register. It may differ from the effective value of
291   // the FP register when that register is used in the JVM for other
292   // purposes (like compiled frames on some platforms).
293   // On other platforms, it is defined so that the stack area used by
294   // this frame goes from real_fp() to sp().
295   intptr_t* real_fp() const;
296 
297   // Deoptimization info, if needed (platform dependent).
298   // Stored in the initial_info field of the unroll info, to be used by
299   // the platform dependent deoptimization blobs.
300   intptr_t *initial_deoptimization_info();
301 
302   // Interpreter frames:
303 
304  private:
305   intptr_t* interpreter_frame_locals() const;
306   intptr_t* interpreter_frame_bcp_addr() const;
307   intptr_t* interpreter_frame_mdp_addr() const;
308 
309  public:
310   // Locals
311 
312   // The _at version returns a pointer because the address is used for GC.
313   intptr_t* interpreter_frame_local_at(int index) const;
314 
315   void interpreter_frame_set_locals(intptr_t* locs);
316 
317   // byte code index
318   jint interpreter_frame_bci() const;
319 
320   // byte code pointer
321   address interpreter_frame_bcp() const;
322   void    interpreter_frame_set_bcp(address bcp);
323 
324   // method data pointer
325   address interpreter_frame_mdp() const;
326   void    interpreter_frame_set_mdp(address dp);
327 
328   // Find receiver out of caller's (compiled) argument list
329   oop retrieve_receiver(RegisterMap *reg_map);
330 
331   // Return the monitor owner and BasicLock for compiled synchronized
332   // native methods. Used by JVMTI's GetLocalInstance method
333   // (via VM_GetReceiver) to retrieve the receiver from a native wrapper frame.
334   BasicLock* get_native_monitor();
335   oop        get_native_receiver();
336 
337   // Find receiver for an invoke when arguments are just pushed on stack (i.e., callee stack-frame is
338   // not setup)
339   oop interpreter_callee_receiver(Symbol* signature);
340 
341 
342   oop* interpreter_callee_receiver_addr(Symbol* signature);
343 
344 
345   // expression stack (may go up or down, direction == 1 or -1)
346  public:
347   intptr_t* interpreter_frame_expression_stack() const;
348 
349   // The _at version returns a pointer because the address is used for GC.
350   intptr_t* interpreter_frame_expression_stack_at(jint offset) const;
351 
352   // top of expression stack
353   intptr_t* interpreter_frame_tos_at(jint offset) const;
354   intptr_t* interpreter_frame_tos_address() const;
355 
356 
357   jint  interpreter_frame_expression_stack_size() const;
358 
359   intptr_t* interpreter_frame_sender_sp() const;
360 
361   // template based interpreter deoptimization support
362   void  set_interpreter_frame_sender_sp(intptr_t* sender_sp);
363   void interpreter_frame_set_monitor_end(BasicObjectLock* value);
364 
365   // Address of the temp oop in the frame. Needed as GC root.
366   oop* interpreter_frame_temp_oop_addr() const;
367 
368   // BasicObjectLocks:
369   //
370   // interpreter_frame_monitor_begin is higher in memory than interpreter_frame_monitor_end
371   // Interpreter_frame_monitor_begin points to one element beyond the oldest one,
372   // interpreter_frame_monitor_end   points to the youngest one, or if there are none,
373   //                                 it points to one beyond where the first element will be.
374   // interpreter_frame_monitor_size  reports the allocation size of a monitor in the interpreter stack.
375   //                                 this value is >= BasicObjectLock::size(), and may be rounded up
376 
377   BasicObjectLock* interpreter_frame_monitor_begin() const;
378   BasicObjectLock* interpreter_frame_monitor_end()   const;
379   BasicObjectLock* next_monitor_in_interpreter_frame(BasicObjectLock* current) const;
380   BasicObjectLock* previous_monitor_in_interpreter_frame(BasicObjectLock* current) const;
381   static int interpreter_frame_monitor_size();
382   static int interpreter_frame_monitor_size_in_bytes();
383 
384   void interpreter_frame_verify_monitor(BasicObjectLock* value) const;
385 
386   // Return/result value from this interpreter frame
387   // If the method return type is T_OBJECT or T_ARRAY populates oop_result
388   // For other (non-T_VOID) the appropriate field in the jvalue is populated
389   // with the result value.
390   // Should only be called when at method exit when the method is not
391   // exiting due to an exception.
392   BasicType interpreter_frame_result(oop* oop_result, jvalue* value_result);
393 
394  public:
395   // Method & constant pool cache
396   Method* interpreter_frame_method() const;
397   void interpreter_frame_set_method(Method* method);
398   Method** interpreter_frame_method_addr() const;
399   ConstantPoolCache** interpreter_frame_cache_addr() const;
400   oop* interpreter_frame_mirror_addr() const;
401 
402   void interpreter_frame_set_mirror(oop mirror);
403 
404  public:
405   // Entry frames
406   JavaCallWrapper* entry_frame_call_wrapper() const { return *entry_frame_call_wrapper_addr(); }
407   JavaCallWrapper* entry_frame_call_wrapper_if_safe(JavaThread* thread) const;
408   JavaCallWrapper** entry_frame_call_wrapper_addr() const;
409   intptr_t* entry_frame_argument_at(int offset) const;
410 
411   // tells whether there is another chunk of Delta stack above
412   bool entry_frame_is_first() const;
413   bool upcall_stub_frame_is_first() const;
414 
415   // Safepoints
416 
417  public:
418   oop saved_oop_result(RegisterMap* map) const;
419   void set_saved_oop_result(RegisterMap* map, oop obj);
420 
421   // For debugging
422  private:
423   const char* print_name() const;
424 
425   void describe_pd(FrameValues& values, int frame_no);
426 
427  public:
428   void print_value() const { print_value_on(tty,nullptr); }
429   void print_value_on(outputStream* st, JavaThread *thread) const;
430   void print_on(outputStream* st) const;
431   void interpreter_frame_print_on(outputStream* st) const;
432   void print_on_error(outputStream* st, char* buf, int buflen, bool verbose = false) const;
433   static void print_C_frame(outputStream* st, char* buf, int buflen, address pc);
434 
435   // Add annotated descriptions of memory locations belonging to this frame to values
436   void describe(FrameValues& values, int frame_no, const RegisterMap* reg_map=nullptr);
437 
438   // Conversion from a VMReg to physical stack location
439   template <typename RegisterMapT>
440   address oopmapreg_to_location(VMReg reg, const RegisterMapT* reg_map) const;
441   template <typename RegisterMapT>
442   oop* oopmapreg_to_oop_location(VMReg reg, const RegisterMapT* reg_map) const;
443 
444   // Oops-do's
445   void oops_compiled_arguments_do(Symbol* signature, bool has_receiver, bool has_appendix, const RegisterMap* reg_map, OopClosure* f) const;
446   void oops_interpreted_do(OopClosure* f, const RegisterMap* map, bool query_oop_map_cache = true) const;
447 
448  private:
449   void oops_interpreted_arguments_do(Symbol* signature, bool has_receiver, OopClosure* f) const;
450 
451   // Iteration of oops
452   void oops_do_internal(OopClosure* f, CodeBlobClosure* cf,
453                         DerivedOopClosure* df, DerivedPointerIterationMode derived_mode,
454                         const RegisterMap* map, bool use_interpreter_oop_map_cache) const;
455 
456   void oops_entry_do(OopClosure* f, const RegisterMap* map) const;
457   void oops_code_blob_do(OopClosure* f, CodeBlobClosure* cf,
458                          DerivedOopClosure* df, DerivedPointerIterationMode derived_mode,
459                          const RegisterMap* map) const;
460  public:
461   // Memory management
462   void oops_do(OopClosure* f, CodeBlobClosure* cf, const RegisterMap* map) {
463 #if COMPILER2_OR_JVMCI
464     DerivedPointerIterationMode dpim = DerivedPointerTable::is_active() ?
465                                        DerivedPointerIterationMode::_with_table :
466                                        DerivedPointerIterationMode::_ignore;
467 #else
468     DerivedPointerIterationMode dpim = DerivedPointerIterationMode::_ignore;;
469 #endif
470     oops_do_internal(f, cf, nullptr, dpim, map, true);
471   }
472 
473   void oops_do(OopClosure* f, CodeBlobClosure* cf, DerivedOopClosure* df, const RegisterMap* map) {
474     oops_do_internal(f, cf, df, DerivedPointerIterationMode::_ignore, map, true);
475   }
476 
477   void oops_do(OopClosure* f, CodeBlobClosure* cf, const RegisterMap* map,
478                DerivedPointerIterationMode derived_mode) const {
479     oops_do_internal(f, cf, nullptr, derived_mode, map, true);
480   }
481 
482   void nmethods_do(CodeBlobClosure* cf) const;
483 
484   // RedefineClasses support for finding live interpreted methods on the stack
485   void metadata_do(MetadataClosure* f) const;
486 
487   // Verification
488   void verify(const RegisterMap* map) const;
489   static bool verify_return_pc(address x);
490   // Usage:
491   // assert(frame::verify_return_pc(return_address), "must be a return pc");
492 
493 #include CPU_HEADER(frame)
494 
495 };
496 
497 #ifndef PRODUCT
498 // A simple class to describe a location on the stack
499 class FrameValue {
500  public:
501   intptr_t* location;
502   char* description;
503   int owner;
504   int priority;
505 
506   FrameValue() {
507     location = nullptr;
508     description = nullptr;
509     owner = -1;
510     priority = 0;
511   }
512 };
513 
514 
515 // A collection of described stack values that can print a symbolic
516 // description of the stack memory.  Interpreter frame values can be
517 // in the caller frames so all the values are collected first and then
518 // sorted before being printed.
519 class FrameValues {
520  private:
521   GrowableArray<FrameValue> _values;
522 
523   static int compare(FrameValue* a, FrameValue* b) {
524     if (a->location == b->location) {
525       return a->priority - b->priority;
526     }
527     return checked_cast<int>(a->location - b->location);
528   }
529 
530   void print_on(outputStream* out, int min_index, int max_index, intptr_t* v0, intptr_t* v1);
531 
532  public:
533   // Used by frame functions to describe locations.
534   void describe(int owner, intptr_t* location, const char* description, int priority = 0);
535 
536 #ifdef ASSERT
537   void validate();
538 #endif
539   void print(JavaThread* thread) { print_on(thread, tty); }
540   void print_on(JavaThread* thread, outputStream* out);
541   void print(stackChunkOop chunk) { print_on(chunk, tty); }
542   void print_on(stackChunkOop chunk, outputStream* out);
543 };
544 
545 #endif
546 
547 
548 #endif // SHARE_RUNTIME_FRAME_HPP