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src/hotspot/cpu/aarch64/frame_aarch64.cpp

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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 void frame::patch_pc(Thread* thread, address pc) {
269   assert(_cb == CodeCache::find_blob(pc), "unexpected pc");
270   address* pc_addr = &(((address*) sp())[-1]);

271   if (TracePcPatching) {
272     tty->print_cr("patch_pc at address " INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "]",
273                   p2i(pc_addr), p2i(*pc_addr), p2i(pc));
274   }
275 


276   // Only generated code frames should be patched, therefore the return address will not be signed.
277   assert(pauth_ptr_is_raw(*pc_addr), "cannot be signed");
278   // Either the return address is the original one or we are going to
279   // patch in the same address that's already there.
280   assert(_pc == *pc_addr || pc == *pc_addr, "must be");

281   *pc_addr = pc;

282   address original_pc = CompiledMethod::get_deopt_original_pc(this);
283   if (original_pc != NULL) {
284     assert(original_pc == _pc, "expected original PC to be stored before patching");
285     _deopt_state = is_deoptimized;
286     // leave _pc as is
287   } else {
288     _deopt_state = not_deoptimized;
289     _pc = pc;
290   }
291 }
292 
293 bool frame::is_interpreted_frame() const  {
294   return Interpreter::contains(pc());
295 }
296 
297 int frame::frame_size(RegisterMap* map) const {
298   frame sender = this->sender(map);
299   return sender.sp() - sp();
300 }
301 
302 intptr_t* frame::entry_frame_argument_at(int offset) const {
303   // convert offset to index to deal with tsi
304   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
305   // Entry frame's arguments are always in relation to unextended_sp()
306   return &unextended_sp()[index];
307 }
308 
309 // sender_sp
310 intptr_t* frame::interpreter_frame_sender_sp() const {
311   assert(is_interpreted_frame(), "interpreted frame expected");
312   return (intptr_t*) at(interpreter_frame_sender_sp_offset);
313 }
314 
315 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
316   assert(is_interpreted_frame(), "interpreted frame expected");
317   ptr_at_put(interpreter_frame_sender_sp_offset, (intptr_t) sender_sp);
318 }
319 
320 
321 // monitor elements
322 
323 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
324   return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset);
325 }
326 




327 BasicObjectLock* frame::interpreter_frame_monitor_end() const {
328   BasicObjectLock* result = (BasicObjectLock*) *addr_at(interpreter_frame_monitor_block_top_offset);
329   // make sure the pointer points inside the frame
330   assert(sp() <= (intptr_t*) result, "monitor end should be above the stack pointer");
331   assert((intptr_t*) result < fp(),  "monitor end should be strictly below the frame pointer");
332   return result;
333 }
334 
335 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) {
336   *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value;
337 }
338 
339 // Used by template based interpreter deoptimization
340 void frame::interpreter_frame_set_last_sp(intptr_t* sp) {
341     *((intptr_t**)addr_at(interpreter_frame_last_sp_offset)) = sp;
342 }
343 
344 frame frame::sender_for_entry_frame(RegisterMap* map) const {
345   assert(map != NULL, "map must be set");
346   // Java frame called from C; skip all C frames and return top C
347   // frame of that chunk as the sender
348   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();

399 
400 //------------------------------------------------------------------------------
401 // frame::adjust_unextended_sp
402 void frame::adjust_unextended_sp() {
403   // On aarch64, sites calling method handle intrinsics and lambda forms are treated
404   // as any other call site. Therefore, no special action is needed when we are
405   // returning to any of these call sites.
406 
407   if (_cb != NULL) {
408     CompiledMethod* sender_cm = _cb->as_compiled_method_or_null();
409     if (sender_cm != NULL) {
410       // If the sender PC is a deoptimization point, get the original PC.
411       if (sender_cm->is_deopt_entry(_pc) ||
412           sender_cm->is_deopt_mh_entry(_pc)) {
413         DEBUG_ONLY(verify_deopt_original_pc(sender_cm, _unextended_sp));
414       }
415     }
416   }
417 }
418 
419 //------------------------------------------------------------------------------
420 // frame::update_map_with_saved_link
421 void frame::update_map_with_saved_link(RegisterMap* map, intptr_t** link_addr) {
422   // The interpreter and compiler(s) always save fp in a known
423   // location on entry. We must record where that location is
424   // so that if fp was live on callout from c2 we can find
425   // the saved copy no matter what it called.
426 
427   // Since the interpreter always saves fp if we record where it is then
428   // we don't have to always save fp on entry and exit to c2 compiled
429   // code, on entry will be enough.
430   map->set_location(rfp->as_VMReg(), (address) link_addr);
431   // this is weird "H" ought to be at a higher address however the
432   // oopMaps seems to have the "H" regs at the same address and the
433   // vanilla register.
434   // XXXX make this go away
435   if (true) {
436     map->set_location(rfp->as_VMReg()->next(), (address) link_addr);
437   }
438 }
439 
440 
441 //------------------------------------------------------------------------------
442 // frame::sender_for_interpreter_frame
443 frame frame::sender_for_interpreter_frame(RegisterMap* map) const {
444   // SP is the raw SP from the sender after adapter or interpreter
445   // extension.
446   intptr_t* sender_sp = this->sender_sp();
447 
448   // This is the sp before any possible extension (adapter/locals).
449   intptr_t* unextended_sp = interpreter_frame_sender_sp();

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   // Use the raw version of pc - the interpreter should not have signed it.

458 
459   return frame(sender_sp, unextended_sp, link(), sender_pc_maybe_signed());
460 }
461 
462 
463 //------------------------------------------------------------------------------
464 // frame::sender_for_compiled_frame
465 frame frame::sender_for_compiled_frame(RegisterMap* map) const {
466   // we cannot rely upon the last fp having been saved to the thread
467   // in C2 code but it will have been pushed onto the stack. so we
468   // have to find it relative to the unextended sp
469 
470   assert(_cb->frame_size() >= 0, "must have non-zero frame size");
471   intptr_t* l_sender_sp = unextended_sp() + _cb->frame_size();
472   intptr_t* unextended_sp = l_sender_sp;
473 
474   // the return_address is always the word on the stack
475   address sender_pc = (address) *(l_sender_sp-1);
476 
477   intptr_t** saved_fp_addr = (intptr_t**) (l_sender_sp - frame::sender_sp_offset);
478 
479   // assert (sender_sp() == l_sender_sp, "should be");
480   // assert (*saved_fp_addr == link(), "should be");
481 
482   if (map->update_map()) {
483     // Tell GC to use argument oopmaps for some runtime stubs that need it.
484     // For C1, the runtime stub might not have oop maps, so set this flag
485     // outside of update_register_map.
486     map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
487     if (_cb->oop_maps() != NULL) {
488       OopMapSet::update_register_map(this, map);
489     }
490 
491     // Since the prolog does the save and restore of FP there is no
492     // oopmap for it so we must fill in its location as if there was
493     // an oopmap entry since if our caller was compiled code there
494     // could be live jvm state in it.
495     update_map_with_saved_link(map, saved_fp_addr);
496   }
497 
498   return frame(l_sender_sp, unextended_sp, *saved_fp_addr, sender_pc);
499 }
500 
501 //------------------------------------------------------------------------------
502 // frame::sender_raw
503 frame frame::sender_raw(RegisterMap* map) const {
504   // Default is we done have to follow them. The sender_for_xxx will
505   // update it accordingly
506    map->set_include_argument_oops(false);
507 
508   if (is_entry_frame())
509     return sender_for_entry_frame(map);
510   if (is_interpreted_frame())
511     return sender_for_interpreter_frame(map);
512   assert(_cb == CodeCache::find_blob(pc()),"Must be the same");
513 
514   // This test looks odd: why is it not is_compiled_frame() ?  That's
515   // because stubs also have OOP maps.
516   if (_cb != NULL) {
517     return sender_for_compiled_frame(map);
518   }
519 
520   // Must be native-compiled frame, i.e. the marshaling code for native
521   // methods that exists in the core system.
522 
523   return frame(sender_sp(), link(), sender_pc());
524 }
525 
526 frame frame::sender(RegisterMap* map) const {
527   frame result = sender_raw(map);
528 
529   if (map->process_frames()) {
530     StackWatermarkSet::on_iteration(map->thread(), result);
531   }
532 
533   return result;
534 }
535 
536 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
537   assert(is_interpreted_frame(), "Not an interpreted frame");
538   // These are reasonable sanity checks
539   if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
540     return false;
541   }
542   if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
543     return false;
544   }
545   if (fp() + interpreter_frame_initial_sp_offset < sp()) {

622       break;
623     }
624     case T_BOOLEAN : value_result->z = *(jboolean*)tos_addr; break;
625     case T_BYTE    : value_result->b = *(jbyte*)tos_addr; break;
626     case T_CHAR    : value_result->c = *(jchar*)tos_addr; break;
627     case T_SHORT   : value_result->s = *(jshort*)tos_addr; break;
628     case T_INT     : value_result->i = *(jint*)tos_addr; break;
629     case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
630     case T_FLOAT   : {
631         value_result->f = *(jfloat*)tos_addr;
632       break;
633     }
634     case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
635     case T_VOID    : /* Nothing to do */ break;
636     default        : ShouldNotReachHere();
637   }
638 
639   return type;
640 }
641 


642 

643 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
644   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
645   return &interpreter_frame_tos_address()[index];
646 }
647 
648 #ifndef PRODUCT
649 
650 #define DESCRIBE_FP_OFFSET(name) \
651   values.describe(frame_no, fp() + frame::name##_offset, #name)
652 
653 void frame::describe_pd(FrameValues& values, int frame_no) {
654   if (is_interpreted_frame()) {
655     DESCRIBE_FP_OFFSET(interpreter_frame_sender_sp);
656     DESCRIBE_FP_OFFSET(interpreter_frame_last_sp);
657     DESCRIBE_FP_OFFSET(interpreter_frame_method);
658     DESCRIBE_FP_OFFSET(interpreter_frame_mdp);
659     DESCRIBE_FP_OFFSET(interpreter_frame_mirror);
660     DESCRIBE_FP_OFFSET(interpreter_frame_cache);
661     DESCRIBE_FP_OFFSET(interpreter_frame_locals);
662     DESCRIBE_FP_OFFSET(interpreter_frame_bcp);
663     DESCRIBE_FP_OFFSET(interpreter_frame_initial_sp);
664   }












665 }
666 #endif
667 
668 intptr_t *frame::initial_deoptimization_info() {
669   // Not used on aarch64, but we must return something.
670   return NULL;
671 }
672 
673 intptr_t* frame::real_fp() const {
674   if (_cb != NULL) {
675     // use the frame size if valid
676     int size = _cb->frame_size();
677     if (size > 0) {
678       return unextended_sp() + size;
679     }
680   }
681   // else rely on fp()
682   assert(! is_compiled_frame(), "unknown compiled frame size");
683   return fp();
684 }
685 
686 #undef DESCRIBE_FP_OFFSET
687 
688 #define DESCRIBE_FP_OFFSET(name)                     \
689   {                                                  \
690     uintptr_t *p = (uintptr_t *)fp;                  \
691     printf(INTPTR_FORMAT " " INTPTR_FORMAT " %s\n",  \
692            (uintptr_t)(p + frame::name##_offset),    \
693            p[frame::name##_offset], #name);          \
694   }
695 
696 static THREAD_LOCAL uintptr_t nextfp;
697 static THREAD_LOCAL uintptr_t nextpc;
698 static THREAD_LOCAL uintptr_t nextsp;
699 static THREAD_LOCAL RegisterMap *reg_map;
700 
701 static void printbc(Method *m, intptr_t bcx) {
702   const char *name;
703   char buf[16];

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 void frame::patch_pc(Thread* thread, address pc) {
269   assert(_cb == CodeCache::find_blob(pc), "unexpected pc");
270   address* pc_addr = &(((address*) sp())[-1]);
271 
272   if (TracePcPatching) {
273     tty->print_cr("patch_pc at address " INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "]",
274                   p2i(pc_addr), p2i(*pc_addr), p2i(pc));
275   }
276 
277   assert(!Continuation::is_return_barrier_entry(*pc_addr), "return barrier");
278   
279   // Only generated code frames should be patched, therefore the return address will not be signed.
280   assert(pauth_ptr_is_raw(*pc_addr), "cannot be signed");
281   // Either the return address is the original one or we are going to
282   // patch in the same address that's already there.
283   assert(_pc == *pc_addr || pc == *pc_addr || *pc_addr == 0, "must be (pc: " INTPTR_FORMAT " _pc: " INTPTR_FORMAT " pc_addr: " INTPTR_FORMAT " *pc_addr: " INTPTR_FORMAT  " sp: " INTPTR_FORMAT ")", p2i(pc), p2i(_pc), p2i(pc_addr), p2i(*pc_addr), p2i(sp()));
284   DEBUG_ONLY(address old_pc = _pc;)
285   *pc_addr = pc;
286   _pc = pc; // must be set before call to get_deopt_original_pc
287   address original_pc = CompiledMethod::get_deopt_original_pc(this);
288   if (original_pc != NULL) {
289     assert(original_pc == old_pc, "expected original PC to be stored before patching");
290     _deopt_state = is_deoptimized;
291     _pc = original_pc;
292   } else {
293     _deopt_state = not_deoptimized;

294   }
295 }
296 









297 intptr_t* frame::entry_frame_argument_at(int offset) const {
298   // convert offset to index to deal with tsi
299   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
300   // Entry frame's arguments are always in relation to unextended_sp()
301   return &unextended_sp()[index];
302 }
303 
304 // sender_sp
305 intptr_t* frame::interpreter_frame_sender_sp() const {
306   assert(is_interpreted_frame(), "interpreted frame expected");
307   return (intptr_t*) at(interpreter_frame_sender_sp_offset);
308 }
309 
310 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
311   assert(is_interpreted_frame(), "interpreted frame expected");
312   ptr_at_put(interpreter_frame_sender_sp_offset, (intptr_t) sender_sp);
313 }
314 
315 
316 // monitor elements
317 
318 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
319   return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset);
320 }
321 
322 template BasicObjectLock* frame::interpreter_frame_monitor_end<true>() const;
323 template BasicObjectLock* frame::interpreter_frame_monitor_end<false>() const;
324 
325 template <bool relative>
326 BasicObjectLock* frame::interpreter_frame_monitor_end() const {
327   BasicObjectLock* result = (BasicObjectLock*) at<relative>(interpreter_frame_monitor_block_top_offset);
328   // make sure the pointer points inside the frame
329   assert(sp() <= (intptr_t*) result, "monitor end should be above the stack pointer");
330   assert((intptr_t*) result < fp(),  "monitor end should be strictly below the frame pointer");
331   return result;
332 }
333 
334 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) {
335   *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value;
336 }
337 
338 // Used by template based interpreter deoptimization
339 void frame::interpreter_frame_set_last_sp(intptr_t* sp) {
340     *((intptr_t**)addr_at(interpreter_frame_last_sp_offset)) = sp;
341 }
342 
343 frame frame::sender_for_entry_frame(RegisterMap* map) const {
344   assert(map != NULL, "map must be set");
345   // Java frame called from C; skip all C frames and return top C
346   // frame of that chunk as the sender
347   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();

398 
399 //------------------------------------------------------------------------------
400 // frame::adjust_unextended_sp
401 void frame::adjust_unextended_sp() {
402   // On aarch64, sites calling method handle intrinsics and lambda forms are treated
403   // as any other call site. Therefore, no special action is needed when we are
404   // returning to any of these call sites.
405 
406   if (_cb != NULL) {
407     CompiledMethod* sender_cm = _cb->as_compiled_method_or_null();
408     if (sender_cm != NULL) {
409       // If the sender PC is a deoptimization point, get the original PC.
410       if (sender_cm->is_deopt_entry(_pc) ||
411           sender_cm->is_deopt_mh_entry(_pc)) {
412         DEBUG_ONLY(verify_deopt_original_pc(sender_cm, _unextended_sp));
413       }
414     }
415   }
416 }
417 





















418 
419 //------------------------------------------------------------------------------
420 // frame::sender_for_interpreter_frame
421 frame frame::sender_for_interpreter_frame(RegisterMap* map) const {
422   // SP is the raw SP from the sender after adapter or interpreter
423   // extension.
424   intptr_t* sender_sp = this->sender_sp();
425 
426   // This is the sp before any possible extension (adapter/locals).
427   intptr_t* unextended_sp = interpreter_frame_sender_sp();
428   intptr_t* sender_fp = link();
429 
430 #if COMPILER2_OR_JVMCI
431   if (map->update_map()) {
432     update_map_with_saved_link(map, (intptr_t**) addr_at(link_offset));
433   }
434 #endif // COMPILER2_OR_JVMCI
435 
436   // Use the raw version of pc - the interpreter should not have signed it.
437   address sender_pc = this->sender_pc_maybe_signed();
438 
439   if (Continuation::is_return_barrier_entry(sender_pc)) {	
440     if (map->walk_cont()) { // about to walk into an h-stack	
441       return Continuation::top_frame(*this, map);	
442     } else {
443       Continuation::fix_continuation_bottom_sender(map->thread(), *this, &sender_pc, &unextended_sp);

























444     }






445   }
446 
447   return frame(sender_sp, unextended_sp, sender_fp, sender_pc);
448 }
449 
450 //------------------------------------------------------------------------------
451 // frame::sender























452 frame frame::sender(RegisterMap* map) const {
453   frame result = sender_raw(map);
454 
455   if (map->process_frames()) {
456     StackWatermarkSet::on_iteration(map->thread(), result);
457   }
458 
459   return result;
460 }
461 
462 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
463   assert(is_interpreted_frame(), "Not an interpreted frame");
464   // These are reasonable sanity checks
465   if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
466     return false;
467   }
468   if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
469     return false;
470   }
471   if (fp() + interpreter_frame_initial_sp_offset < sp()) {

548       break;
549     }
550     case T_BOOLEAN : value_result->z = *(jboolean*)tos_addr; break;
551     case T_BYTE    : value_result->b = *(jbyte*)tos_addr; break;
552     case T_CHAR    : value_result->c = *(jchar*)tos_addr; break;
553     case T_SHORT   : value_result->s = *(jshort*)tos_addr; break;
554     case T_INT     : value_result->i = *(jint*)tos_addr; break;
555     case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
556     case T_FLOAT   : {
557         value_result->f = *(jfloat*)tos_addr;
558       break;
559     }
560     case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
561     case T_VOID    : /* Nothing to do */ break;
562     default        : ShouldNotReachHere();
563   }
564 
565   return type;
566 }
567 
568 template intptr_t* frame::interpreter_frame_tos_at<false>(jint offset) const;
569 template intptr_t* frame::interpreter_frame_tos_at<true >(jint offset) const;
570 
571 template <bool relative>
572 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
573   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
574   return &interpreter_frame_tos_address<relative>()[index];
575 }
576 
577 #ifndef PRODUCT
578 
579 #define DESCRIBE_FP_OFFSET(name) \
580   values.describe(frame_no, fp() + frame::name##_offset, #name)
581 
582 void frame::describe_pd(FrameValues& values, int frame_no) {
583   if (is_interpreted_frame()) {
584     DESCRIBE_FP_OFFSET(interpreter_frame_sender_sp);
585     DESCRIBE_FP_OFFSET(interpreter_frame_last_sp);
586     DESCRIBE_FP_OFFSET(interpreter_frame_method);
587     DESCRIBE_FP_OFFSET(interpreter_frame_mdp);
588     DESCRIBE_FP_OFFSET(interpreter_frame_mirror);
589     DESCRIBE_FP_OFFSET(interpreter_frame_cache);
590     DESCRIBE_FP_OFFSET(interpreter_frame_locals);
591     DESCRIBE_FP_OFFSET(interpreter_frame_bcp);
592     DESCRIBE_FP_OFFSET(interpreter_frame_initial_sp);
593   }
594 
595   if (is_java_frame()) {
596     address ret_pc = *(address*)(real_fp() - return_addr_offset);
597     values.describe(frame_no, real_fp() - return_addr_offset, Continuation::is_return_barrier_entry(ret_pc) ? "return address (return barrier)" : "return address");
598     values.describe(-1, real_fp() - sender_sp_offset, "saved fp", 2);
599   }
600 }
601 
602 void frame::describe_top_pd(FrameValues& values) {
603   address ret_pc_callee = *(address*)(sp() - return_addr_offset);
604   values.describe(-1, sp() - return_addr_offset, Continuation::is_return_barrier_entry(ret_pc_callee) ? "return address (return barrier)" : "return address");
605   values.describe(-1, sp() - sender_sp_offset, "saved fp", 2);
606 }
607 #endif
608 
609 intptr_t *frame::initial_deoptimization_info() {
610   // Not used on aarch64, but we must return something.
611   return NULL;













612 }
613 
614 #undef DESCRIBE_FP_OFFSET
615 
616 #define DESCRIBE_FP_OFFSET(name)                     \
617   {                                                  \
618     uintptr_t *p = (uintptr_t *)fp;                  \
619     printf(INTPTR_FORMAT " " INTPTR_FORMAT " %s\n",  \
620            (uintptr_t)(p + frame::name##_offset),    \
621            p[frame::name##_offset], #name);          \
622   }
623 
624 static THREAD_LOCAL uintptr_t nextfp;
625 static THREAD_LOCAL uintptr_t nextpc;
626 static THREAD_LOCAL uintptr_t nextsp;
627 static THREAD_LOCAL RegisterMap *reg_map;
628 
629 static void printbc(Method *m, intptr_t bcx) {
630   const char *name;
631   char buf[16];
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