1 /*
  2  * Copyright (c) 1997, 2022, 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 #include "precompiled.hpp"
 26 #include "compiler/oopMap.hpp"
 27 #include "interpreter/interpreter.hpp"
 28 #include "memory/resourceArea.hpp"
 29 #include "memory/universe.hpp"
 30 #include "oops/markWord.hpp"
 31 #include "oops/method.hpp"
 32 #include "oops/oop.inline.hpp"
 33 #include "prims/methodHandles.hpp"
 34 #include "runtime/continuation.hpp"
 35 #include "runtime/frame.inline.hpp"
 36 #include "runtime/handles.inline.hpp"
 37 #include "runtime/javaCalls.hpp"
 38 #include "runtime/monitorChunk.hpp"
 39 #include "runtime/signature.hpp"
 40 #include "runtime/stackWatermarkSet.hpp"
 41 #include "runtime/stubCodeGenerator.hpp"
 42 #include "runtime/stubRoutines.hpp"
 43 #include "vmreg_x86.inline.hpp"
 44 #include "utilities/formatBuffer.hpp"
 45 #ifdef COMPILER1
 46 #include "c1/c1_Runtime1.hpp"
 47 #include "runtime/vframeArray.hpp"
 48 #endif
 49 
 50 #ifdef ASSERT
 51 void RegisterMap::check_location_valid() {
 52 }
 53 #endif
 54 
 55 // Profiling/safepoint support
 56 
 57 bool frame::safe_for_sender(JavaThread *thread) {
 58   if (is_heap_frame()) {
 59     return true;
 60   }
 61   address   sp = (address)_sp;
 62   address   fp = (address)_fp;
 63   address   unextended_sp = (address)_unextended_sp;
 64 
 65   // consider stack guards when trying to determine "safe" stack pointers
 66   // sp must be within the usable part of the stack (not in guards)
 67   if (!thread->is_in_usable_stack(sp)) {
 68     return false;
 69   }
 70 
 71   // unextended sp must be within the stack and above or equal sp
 72   if (!thread->is_in_stack_range_incl(unextended_sp, sp)) {
 73     return false;
 74   }
 75 
 76   // an fp must be within the stack and above (but not equal) sp
 77   // second evaluation on fp+ is added to handle situation where fp is -1
 78   bool fp_safe = thread->is_in_stack_range_excl(fp, sp) &&
 79                  thread->is_in_full_stack_checked(fp + (return_addr_offset * sizeof(void*)));
 80 
 81   // We know sp/unextended_sp are safe only fp is questionable here
 82 
 83   // If the current frame is known to the code cache then we can attempt to
 84   // construct the sender and do some validation of it. This goes a long way
 85   // toward eliminating issues when we get in frame construction code
 86 
 87   if (_cb != NULL ) {
 88 
 89     // First check if frame is complete and tester is reliable
 90     // Unfortunately we can only check frame complete for runtime stubs and nmethod
 91     // other generic buffer blobs are more problematic so we just assume they are
 92     // ok. adapter blobs never have a frame complete and are never ok.
 93 
 94     if (!_cb->is_frame_complete_at(_pc)) {
 95       if (_cb->is_compiled() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
 96         return false;
 97       }
 98     }
 99 
100     // Could just be some random pointer within the codeBlob
101     if (!_cb->code_contains(_pc)) {
102       return false;
103     }
104 
105     // Entry frame checks
106     if (is_entry_frame()) {
107       // an entry frame must have a valid fp.
108       return fp_safe && is_entry_frame_valid(thread);
109     } else if (is_upcall_stub_frame()) {
110       return fp_safe;
111     }
112 
113     intptr_t* sender_sp = NULL;
114     intptr_t* sender_unextended_sp = NULL;
115     address   sender_pc = NULL;
116     intptr_t* saved_fp =  NULL;
117 
118     if (is_interpreted_frame()) {
119       // fp must be safe
120       if (!fp_safe) {
121         return false;
122       }
123 
124       sender_pc = (address) this->fp()[return_addr_offset];
125       // for interpreted frames, the value below is the sender "raw" sp,
126       // which can be different from the sender unextended sp (the sp seen
127       // by the sender) because of current frame local variables
128       sender_sp = (intptr_t*) addr_at(sender_sp_offset);
129       sender_unextended_sp = (intptr_t*) this->fp()[interpreter_frame_sender_sp_offset];
130       saved_fp = (intptr_t*) this->fp()[link_offset];
131 
132     } else {
133       // must be some sort of compiled/runtime frame
134       // fp does not have to be safe (although it could be check for c1?)
135 
136       // check for a valid frame_size, otherwise we are unlikely to get a valid sender_pc
137       if (_cb->frame_size() <= 0) {
138         return false;
139       }
140 
141       sender_sp = _unextended_sp + _cb->frame_size();
142       // Is sender_sp safe?
143       if (!thread->is_in_full_stack_checked((address)sender_sp)) {
144         return false;
145       }
146       // On Intel the return_address is always the word on the stack
147       sender_pc = (address) *(sender_sp-1);
148       // Note: frame::sender_sp_offset is only valid for compiled frame
149       intptr_t** saved_fp_addr = (intptr_t**) (sender_sp - frame::sender_sp_offset);
150       saved_fp = *saved_fp_addr;
151 
152       // Repair the sender sp if this is a method with scalarized inline type args
153       sender_sp = repair_sender_sp(sender_sp, saved_fp_addr);
154       sender_unextended_sp = sender_sp;
155     }
156     if (Continuation::is_return_barrier_entry(sender_pc)) {
157       // If our sender_pc is the return barrier, then our "real" sender is the continuation entry
158       frame s = Continuation::continuation_bottom_sender(thread, *this, sender_sp);
159       sender_sp = s.sp();
160       sender_pc = s.pc();
161     }
162 
163     // If the potential sender is the interpreter then we can do some more checking
164     if (Interpreter::contains(sender_pc)) {
165 
166       // ebp is always saved in a recognizable place in any code we generate. However
167       // only if the sender is interpreted/call_stub (c1 too?) are we certain that the saved ebp
168       // is really a frame pointer.
169 
170       if (!thread->is_in_stack_range_excl((address)saved_fp, (address)sender_sp)) {
171         return false;
172       }
173 
174       // construct the potential sender
175 
176       frame sender(sender_sp, sender_unextended_sp, saved_fp, sender_pc);
177 
178       return sender.is_interpreted_frame_valid(thread);
179 
180     }
181 
182     // We must always be able to find a recognizable pc
183     CodeBlob* sender_blob = CodeCache::find_blob(sender_pc);
184     if (sender_pc == NULL ||  sender_blob == NULL) {
185       return false;
186     }
187 
188     // Could just be some random pointer within the codeBlob
189     if (!sender_blob->code_contains(sender_pc)) {
190       return false;
191     }
192 
193     // We should never be able to see an adapter if the current frame is something from code cache
194     if (sender_blob->is_adapter_blob()) {
195       return false;
196     }
197 
198     // Could be the call_stub
199     if (StubRoutines::returns_to_call_stub(sender_pc)) {
200       if (!thread->is_in_stack_range_excl((address)saved_fp, (address)sender_sp)) {
201         return false;
202       }
203 
204       // construct the potential sender
205 
206       frame sender(sender_sp, sender_unextended_sp, saved_fp, sender_pc);
207 
208       // Validate the JavaCallWrapper an entry frame must have
209       address jcw = (address)sender.entry_frame_call_wrapper();
210 
211       return thread->is_in_stack_range_excl(jcw, (address)sender.fp());
212     } else if (sender_blob->is_upcall_stub()) {
213       return false;
214     }
215 
216     CompiledMethod* nm = sender_blob->as_compiled_method_or_null();
217     if (nm != NULL) {
218         if (nm->is_deopt_mh_entry(sender_pc) || nm->is_deopt_entry(sender_pc) ||
219             nm->method()->is_method_handle_intrinsic()) {
220             return false;
221         }
222     }
223 
224     // If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size
225     // because the return address counts against the callee's frame.
226 
227     if (sender_blob->frame_size() <= 0) {
228       assert(!sender_blob->is_compiled(), "should count return address at least");
229       return false;
230     }
231 
232     // We should never be able to see anything here except an nmethod. If something in the
233     // code cache (current frame) is called by an entity within the code cache that entity
234     // should not be anything but the call stub (already covered), the interpreter (already covered)
235     // or an nmethod.
236 
237     if (!sender_blob->is_compiled()) {
238         return false;
239     }
240 
241     // Could put some more validation for the potential non-interpreted sender
242     // frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
243 
244     // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
245 
246     // We've validated the potential sender that would be created
247     return true;
248   }
249 
250   // Must be native-compiled frame. Since sender will try and use fp to find
251   // linkages it must be safe
252 
253   if (!fp_safe) {
254     return false;
255   }
256 
257   // Will the pc we fetch be non-zero (which we'll find at the oldest frame)
258 
259   if ( (address) this->fp()[return_addr_offset] == NULL) return false;
260 
261 
262   // could try and do some more potential verification of native frame if we could think of some...
263 
264   return true;
265 
266 }
267 
268 
269 void frame::patch_pc(Thread* thread, address pc) {
270   assert(_cb == CodeCache::find_blob(pc), "unexpected pc");
271   address* pc_addr = &(((address*) sp())[-1]);
272 
273   if (TracePcPatching) {
274     tty->print_cr("patch_pc at address " INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "]",
275                   p2i(pc_addr), p2i(*pc_addr), p2i(pc));
276   }
277   // Either the return address is the original one or we are going to
278   // patch in the same address that's already there.
279 
280   assert(!Continuation::is_return_barrier_entry(*pc_addr), "return barrier");
281 
282   assert(_pc == *pc_addr || pc == *pc_addr || *pc_addr == 0, "");
283   DEBUG_ONLY(address old_pc = _pc;)
284   *pc_addr = pc;
285   _pc = pc; // must be set before call to get_deopt_original_pc
286   address original_pc = CompiledMethod::get_deopt_original_pc(this);
287   if (original_pc != NULL) {
288     assert(original_pc == old_pc, "expected original PC to be stored before patching");
289     _deopt_state = is_deoptimized;
290     _pc = original_pc;
291   } else {
292     _deopt_state = not_deoptimized;
293   }
294   assert(!is_compiled_frame() || !_cb->as_compiled_method()->is_deopt_entry(_pc), "must be");
295 
296 #ifdef ASSERT
297   {
298     frame f(this->sp(), this->unextended_sp(), this->fp(), pc);
299     assert(f.is_deoptimized_frame() == this->is_deoptimized_frame() && f.pc() == this->pc() && f.raw_pc() == this->raw_pc(),
300       "must be (f.is_deoptimized_frame(): %d this->is_deoptimized_frame(): %d "
301       "f.pc(): " INTPTR_FORMAT " this->pc(): " INTPTR_FORMAT " f.raw_pc(): " INTPTR_FORMAT " this->raw_pc(): " INTPTR_FORMAT ")",
302       f.is_deoptimized_frame(), this->is_deoptimized_frame(), p2i(f.pc()), p2i(this->pc()), p2i(f.raw_pc()), p2i(this->raw_pc()));
303   }
304 #endif
305 }
306 
307 intptr_t* frame::entry_frame_argument_at(int offset) const {
308   // convert offset to index to deal with tsi
309   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
310   // Entry frame's arguments are always in relation to unextended_sp()
311   return &unextended_sp()[index];
312 }
313 
314 // sender_sp
315 
316 intptr_t* frame::interpreter_frame_sender_sp() const {
317   assert(is_interpreted_frame(), "interpreted frame expected");
318   return (intptr_t*) at(interpreter_frame_sender_sp_offset);
319 }
320 
321 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
322   assert(is_interpreted_frame(), "interpreted frame expected");
323   ptr_at_put(interpreter_frame_sender_sp_offset, (intptr_t) sender_sp);
324 }
325 
326 
327 // monitor elements
328 
329 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
330   return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset);
331 }
332 
333 BasicObjectLock* frame::interpreter_frame_monitor_end() const {
334   BasicObjectLock* result = (BasicObjectLock*) at(interpreter_frame_monitor_block_top_offset);
335   // make sure the pointer points inside the frame
336   assert(sp() <= (intptr_t*) result, "monitor end should be above the stack pointer");
337   assert((intptr_t*) result < fp(),  "monitor end should be strictly below the frame pointer: result: " INTPTR_FORMAT " fp: " INTPTR_FORMAT, p2i(result), p2i(fp()));
338   return result;
339 }
340 
341 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) {
342   *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value;
343 }
344 
345 // Used by template based interpreter deoptimization
346 void frame::interpreter_frame_set_last_sp(intptr_t* sp) {
347     *((intptr_t**)addr_at(interpreter_frame_last_sp_offset)) = sp;
348 }
349 
350 frame frame::sender_for_entry_frame(RegisterMap* map) const {
351   assert(map != NULL, "map must be set");
352   // Java frame called from C; skip all C frames and return top C
353   // frame of that chunk as the sender
354   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
355   assert(!entry_frame_is_first(), "next Java fp must be non zero");
356   assert(jfa->last_Java_sp() > sp(), "must be above this frame on stack");
357   // Since we are walking the stack now this nested anchor is obviously walkable
358   // even if it wasn't when it was stacked.
359   jfa->make_walkable();
360   map->clear();
361   assert(map->include_argument_oops(), "should be set by clear");
362   frame fr(jfa->last_Java_sp(), jfa->last_Java_fp(), jfa->last_Java_pc());
363 
364   return fr;
365 }
366 
367 UpcallStub::FrameData* UpcallStub::frame_data_for_frame(const frame& frame) const {
368   assert(frame.is_upcall_stub_frame(), "wrong frame");
369   // need unextended_sp here, since normal sp is wrong for interpreter callees
370   return reinterpret_cast<UpcallStub::FrameData*>(
371     reinterpret_cast<address>(frame.unextended_sp()) + in_bytes(_frame_data_offset));
372 }
373 
374 bool frame::upcall_stub_frame_is_first() const {
375   assert(is_upcall_stub_frame(), "must be optimzed entry frame");
376   UpcallStub* blob = _cb->as_upcall_stub();
377   JavaFrameAnchor* jfa = blob->jfa_for_frame(*this);
378   return jfa->last_Java_sp() == NULL;
379 }
380 
381 frame frame::sender_for_upcall_stub_frame(RegisterMap* map) const {
382   assert(map != NULL, "map must be set");
383   UpcallStub* blob = _cb->as_upcall_stub();
384   // Java frame called from C; skip all C frames and return top C
385   // frame of that chunk as the sender
386   JavaFrameAnchor* jfa = blob->jfa_for_frame(*this);
387   assert(!upcall_stub_frame_is_first(), "must have a frame anchor to go back to");
388   assert(jfa->last_Java_sp() > sp(), "must be above this frame on stack");
389   // Since we are walking the stack now this nested anchor is obviously walkable
390   // even if it wasn't when it was stacked.
391   jfa->make_walkable();
392   map->clear();
393   assert(map->include_argument_oops(), "should be set by clear");
394   frame fr(jfa->last_Java_sp(), jfa->last_Java_fp(), jfa->last_Java_pc());
395 
396   return fr;
397 }
398 
399 //------------------------------------------------------------------------------
400 // frame::verify_deopt_original_pc
401 //
402 // Verifies the calculated original PC of a deoptimization PC for the
403 // given unextended SP.
404 #ifdef ASSERT
405 void frame::verify_deopt_original_pc(CompiledMethod* nm, intptr_t* unextended_sp) {
406   frame fr;
407 
408   // This is ugly but it's better than to change {get,set}_original_pc
409   // to take an SP value as argument.  And it's only a debugging
410   // method anyway.
411   fr._unextended_sp = unextended_sp;
412 
413   address original_pc = nm->get_original_pc(&fr);
414   assert(nm->insts_contains_inclusive(original_pc),
415          "original PC must be in the main code section of the compiled method (or must be immediately following it) original_pc: " INTPTR_FORMAT " unextended_sp: " INTPTR_FORMAT " name: %s", p2i(original_pc), p2i(unextended_sp), nm->name());
416 }
417 #endif
418 
419 //------------------------------------------------------------------------------
420 // frame::adjust_unextended_sp
421 #ifdef ASSERT
422 void frame::adjust_unextended_sp() {
423   // On x86, sites calling method handle intrinsics and lambda forms are treated
424   // as any other call site. Therefore, no special action is needed when we are
425   // returning to any of these call sites.
426 
427   if (_cb != NULL) {
428     CompiledMethod* sender_cm = _cb->as_compiled_method_or_null();
429     if (sender_cm != NULL) {
430       // If the sender PC is a deoptimization point, get the original PC.
431       if (sender_cm->is_deopt_entry(_pc) ||
432           sender_cm->is_deopt_mh_entry(_pc)) {
433         verify_deopt_original_pc(sender_cm, _unextended_sp);
434       }
435     }
436   }
437 }
438 #endif
439 
440 //------------------------------------------------------------------------------
441 // frame::sender_for_interpreter_frame
442 frame frame::sender_for_interpreter_frame(RegisterMap* map) const {
443   // SP is the raw SP from the sender after adapter or interpreter
444   // extension.
445   intptr_t* sender_sp = this->sender_sp();
446 
447   // This is the sp before any possible extension (adapter/locals).
448   intptr_t* unextended_sp = interpreter_frame_sender_sp();
449   intptr_t* sender_fp = link();
450 
451 #if COMPILER2_OR_JVMCI
452   if (map->update_map()) {
453     update_map_with_saved_link(map, (intptr_t**) addr_at(link_offset));
454   }
455 #endif // COMPILER2_OR_JVMCI
456 
457   address sender_pc = this->sender_pc();
458 
459   if (Continuation::is_return_barrier_entry(sender_pc)) {
460     if (map->walk_cont()) { // about to walk into an h-stack
461       return Continuation::top_frame(*this, map);
462     } else {
463       return Continuation::continuation_bottom_sender(map->thread(), *this, sender_sp);
464     }
465   }
466 
467   return frame(sender_sp, unextended_sp, sender_fp, sender_pc);
468 }
469 
470 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
471   assert(is_interpreted_frame(), "Not an interpreted frame");
472   // These are reasonable sanity checks
473   if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
474     return false;
475   }
476   if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
477     return false;
478   }
479   if (fp() + interpreter_frame_initial_sp_offset < sp()) {
480     return false;
481   }
482   // These are hacks to keep us out of trouble.
483   // The problem with these is that they mask other problems
484   if (fp() <= sp()) {        // this attempts to deal with unsigned comparison above
485     return false;
486   }
487 
488   // do some validation of frame elements
489   // first the method
490 
491   Method* m = *interpreter_frame_method_addr();
492 
493   // validate the method we'd find in this potential sender
494   if (!Method::is_valid_method(m)) return false;
495 
496   // stack frames shouldn't be much larger than max_stack elements
497   // this test requires the use the unextended_sp which is the sp as seen by
498   // the current frame, and not sp which is the "raw" pc which could point
499   // further because of local variables of the callee method inserted after
500   // method arguments
501   if (fp() - unextended_sp() > 1024 + m->max_stack()*Interpreter::stackElementSize) {
502     return false;
503   }
504 
505   // validate bci/bcp
506 
507   address bcp = interpreter_frame_bcp();
508   if (m->validate_bci_from_bcp(bcp) < 0) {
509     return false;
510   }
511 
512   // validate ConstantPoolCache*
513   ConstantPoolCache* cp = *interpreter_frame_cache_addr();
514   if (MetaspaceObj::is_valid(cp) == false) return false;
515 
516   // validate locals
517 
518   address locals =  (address) *interpreter_frame_locals_addr();
519   return thread->is_in_stack_range_incl(locals, (address)fp());
520 }
521 
522 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
523   assert(is_interpreted_frame(), "interpreted frame expected");
524   Method* method = interpreter_frame_method();
525   BasicType type = method->result_type();
526 
527   intptr_t* tos_addr;
528   if (method->is_native()) {
529     // Prior to calling into the runtime to report the method_exit the possible
530     // return value is pushed to the native stack. If the result is a jfloat/jdouble
531     // then ST0 is saved before EAX/EDX. See the note in generate_native_result
532     tos_addr = (intptr_t*)sp();
533     if (type == T_FLOAT || type == T_DOUBLE) {
534     // QQQ seems like this code is equivalent on the two platforms
535 #ifdef AMD64
536       // This is times two because we do a push(ltos) after pushing XMM0
537       // and that takes two interpreter stack slots.
538       tos_addr += 2 * Interpreter::stackElementWords;
539 #else
540       tos_addr += 2;
541 #endif // AMD64
542     }
543   } else {
544     tos_addr = (intptr_t*)interpreter_frame_tos_address();
545   }
546 
547   switch (type) {
548     case T_OBJECT  :
549     case T_PRIMITIVE_OBJECT:
550     case T_ARRAY   : {
551       oop obj;
552       if (method->is_native()) {
553         obj = cast_to_oop(at(interpreter_frame_oop_temp_offset));
554       } else {
555         oop* obj_p = (oop*)tos_addr;
556         obj = (obj_p == NULL) ? (oop)NULL : *obj_p;
557       }
558       assert(Universe::is_in_heap_or_null(obj), "sanity check");
559       *oop_result = obj;
560       break;
561     }
562     case T_BOOLEAN : value_result->z = *(jboolean*)tos_addr; break;
563     case T_BYTE    : value_result->b = *(jbyte*)tos_addr; break;
564     case T_CHAR    : value_result->c = *(jchar*)tos_addr; break;
565     case T_SHORT   : value_result->s = *(jshort*)tos_addr; break;
566     case T_INT     : value_result->i = *(jint*)tos_addr; break;
567     case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
568     case T_FLOAT   : {
569 #ifdef AMD64
570         value_result->f = *(jfloat*)tos_addr;
571 #else
572       if (method->is_native()) {
573         jdouble d = *(jdouble*)tos_addr;  // Result was in ST0 so need to convert to jfloat
574         value_result->f = (jfloat)d;
575       } else {
576         value_result->f = *(jfloat*)tos_addr;
577       }
578 #endif // AMD64
579       break;
580     }
581     case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
582     case T_VOID    : /* Nothing to do */ break;
583     default        : ShouldNotReachHere();
584   }
585 
586   return type;
587 }
588 
589 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
590   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
591   return &interpreter_frame_tos_address()[index];
592 }
593 
594 #ifndef PRODUCT
595 
596 #define DESCRIBE_FP_OFFSET(name) \
597   values.describe(frame_no, fp() + frame::name##_offset, #name, 1)
598 
599 void frame::describe_pd(FrameValues& values, int frame_no) {
600   if (is_interpreted_frame()) {
601     DESCRIBE_FP_OFFSET(interpreter_frame_sender_sp);
602     DESCRIBE_FP_OFFSET(interpreter_frame_last_sp);
603     DESCRIBE_FP_OFFSET(interpreter_frame_method);
604     DESCRIBE_FP_OFFSET(interpreter_frame_mirror);
605     DESCRIBE_FP_OFFSET(interpreter_frame_mdp);
606     DESCRIBE_FP_OFFSET(interpreter_frame_cache);
607     DESCRIBE_FP_OFFSET(interpreter_frame_locals);
608     DESCRIBE_FP_OFFSET(interpreter_frame_bcp);
609     DESCRIBE_FP_OFFSET(interpreter_frame_initial_sp);
610 #ifdef AMD64
611   } else if (is_entry_frame()) {
612     // This could be more descriptive if we use the enum in
613     // stubGenerator to map to real names but it's most important to
614     // claim these frame slots so the error checking works.
615     for (int i = 0; i < entry_frame_after_call_words; i++) {
616       values.describe(frame_no, fp() - i, err_msg("call_stub word fp - %d", i));
617     }
618 #endif // AMD64
619   }
620 
621   if (is_java_frame() || Continuation::is_continuation_enterSpecial(*this)) {
622     intptr_t* ret_pc_loc;
623     intptr_t* fp_loc;
624     if (is_interpreted_frame()) {
625       ret_pc_loc = fp() + return_addr_offset;
626       fp_loc = fp();
627     } else {
628       ret_pc_loc = real_fp() - return_addr_offset;
629       fp_loc = real_fp() - sender_sp_offset;
630     }
631     address ret_pc = *(address*)ret_pc_loc;
632     values.describe(frame_no, ret_pc_loc,
633       Continuation::is_return_barrier_entry(ret_pc) ? "return address (return barrier)" : "return address");
634     values.describe(-1, fp_loc, "saved fp", 0); // "unowned" as value belongs to sender
635   }
636 }
637 
638 #endif // !PRODUCT
639 
640 intptr_t *frame::initial_deoptimization_info() {
641   // used to reset the saved FP
642   return fp();
643 }
644 
645 #ifndef PRODUCT
646 // This is a generic constructor which is only used by pns() in debug.cpp.
647 frame::frame(void* sp, void* fp, void* pc) {
648   init((intptr_t*)sp, (intptr_t*)fp, (address)pc);
649 }
650 
651 #endif
652 
653 // Check for a method with scalarized inline type arguments that needs
654 // a stack repair and return the repaired sender stack pointer.
655 intptr_t* frame::repair_sender_sp(intptr_t* sender_sp, intptr_t** saved_fp_addr) const {
656   CompiledMethod* cm = _cb->as_compiled_method_or_null();
657   if (cm != NULL && cm->needs_stack_repair()) {
658     // The stack increment resides just below the saved rbp on the stack
659     // and does not account for the return address.
660     intptr_t* real_frame_size_addr = (intptr_t*) (saved_fp_addr - 1);
661     int real_frame_size = ((*real_frame_size_addr) + wordSize) / wordSize;
662     assert(real_frame_size >= _cb->frame_size() && real_frame_size <= 1000000, "invalid frame size");
663     sender_sp = unextended_sp() + real_frame_size;
664   }
665   return sender_sp;
666 }
667 
668 void JavaFrameAnchor::make_walkable() {
669   // last frame set?
670   if (last_Java_sp() == NULL) return;
671   // already walkable?
672   if (walkable()) return;
673   vmassert(last_Java_pc() == NULL, "already walkable");
674   _last_Java_pc = (address)_last_Java_sp[-1];
675   vmassert(walkable(), "something went wrong");
676 }