1 /*
2 * Copyright (c) 2008, 2018, 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 "interpreter/interpreter.hpp"
27 #include "memory/resourceArea.hpp"
28 #include "memory/universe.hpp"
29 #include "oops/markWord.hpp"
30 #include "oops/method.hpp"
31 #include "oops/oop.inline.hpp"
32 #include "runtime/frame.inline.hpp"
33 #include "runtime/handles.inline.hpp"
34 #include "runtime/javaCalls.hpp"
35 #include "runtime/monitorChunk.hpp"
36 #include "runtime/os.inline.hpp"
37 #include "runtime/signature.hpp"
38 #include "runtime/stubCodeGenerator.hpp"
39 #include "runtime/stubRoutines.hpp"
40 #include "vmreg_arm.inline.hpp"
41 #ifdef COMPILER1
42 #include "c1/c1_Runtime1.hpp"
43 #include "runtime/vframeArray.hpp"
44 #endif
45 #include "prims/methodHandles.hpp"
46
47 #ifdef ASSERT
48 void RegisterMap::check_location_valid() {
49 }
50 #endif
51
52
53 // Profiling/safepoint support
54
55 bool frame::safe_for_sender(JavaThread *thread) {
56 address sp = (address)_sp;
57 address fp = (address)_fp;
58 address unextended_sp = (address)_unextended_sp;
59
60 static size_t stack_guard_size = os::uses_stack_guard_pages() ?
61 (JavaThread::stack_red_zone_size() + JavaThread::stack_yellow_zone_size()) : 0;
62 size_t usable_stack_size = thread->stack_size() - stack_guard_size;
63
64 // sp must be within the usable part of the stack (not in guards)
65 bool sp_safe = (sp != NULL &&
66 (sp <= thread->stack_base()) &&
67 (sp >= thread->stack_base() - usable_stack_size));
68
69 if (!sp_safe) {
70 return false;
71 }
72
73 bool unextended_sp_safe = (unextended_sp != NULL &&
74 (unextended_sp <= thread->stack_base()) &&
75 (unextended_sp >= sp));
76 if (!unextended_sp_safe) {
77 return false;
78 }
79
80 // We know sp/unextended_sp are safe. Only fp is questionable here.
81
82 bool fp_safe = (fp != NULL &&
83 (fp <= thread->stack_base()) &&
84 fp >= sp);
85
86 if (_cb != NULL ) {
87
88 // First check if frame is complete and tester is reliable
89 // Unfortunately we can only check frame complete for runtime stubs and nmethod
90 // other generic buffer blobs are more problematic so we just assume they are
91 // ok. adapter blobs never have a frame complete and are never ok.
92
93 if (!_cb->is_frame_complete_at(_pc)) {
94 if (_cb->is_compiled() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
95 return false;
96 }
97 }
98
99 // Could just be some random pointer within the codeBlob
100 if (!_cb->code_contains(_pc)) {
101 return false;
102 }
103
104 // Entry frame checks
105 if (is_entry_frame()) {
106 // an entry frame must have a valid fp.
107 return fp_safe && is_entry_frame_valid(thread);
108 }
109
110 intptr_t* sender_sp = NULL;
111 address sender_pc = NULL;
112
113 if (is_interpreted_frame()) {
114 // fp must be safe
115 if (!fp_safe) {
116 return false;
117 }
118
119 sender_pc = (address) this->fp()[return_addr_offset];
120 sender_sp = (intptr_t*) addr_at(sender_sp_offset);
121
122 } else {
123 // must be some sort of compiled/runtime frame
124 // fp does not have to be safe (although it could be check for c1?)
125
126 sender_sp = _unextended_sp + _cb->frame_size();
127 // Is sender_sp safe?
128 if ((address)sender_sp >= thread->stack_base()) {
129 return false;
130 }
131 // With our calling conventions, the return_address should
132 // end up being the word on the stack
133 sender_pc = (address) *(sender_sp - sender_sp_offset + return_addr_offset);
134 }
135
136 // We must always be able to find a recognizable pc
137 CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
138 if (sender_pc == NULL || sender_blob == NULL) {
139 return false;
140 }
141
142
143 // If the potential sender is the interpreter then we can do some more checking
144 if (Interpreter::contains(sender_pc)) {
145
146 // FP is always saved in a recognizable place in any code we generate. However
147 // only if the sender is interpreted/call_stub (c1 too?) are we certain that the saved FP
148 // is really a frame pointer.
149
150 intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset + link_offset);
151 bool saved_fp_safe = ((address)saved_fp <= thread->stack_base()) && (saved_fp > sender_sp);
152
153 if (!saved_fp_safe) {
154 return false;
155 }
156
157 // construct the potential sender
158
159 frame sender(sender_sp, saved_fp, sender_pc);
160
161 return sender.is_interpreted_frame_valid(thread);
162 }
163
164 if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {
165 return false;
166 }
167
168 // Could just be some random pointer within the codeBlob
169 if (!sender_blob->code_contains(sender_pc)) {
170 return false;
171 }
172
173 // We should never be able to see an adapter if the current frame is something from code cache
174 if (sender_blob->is_adapter_blob()) {
175 return false;
176 }
177
178 // Could be the call_stub
179 if (StubRoutines::returns_to_call_stub(sender_pc)) {
180 intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset + link_offset);
181 bool saved_fp_safe = ((address)saved_fp <= thread->stack_base()) && (saved_fp >= sender_sp);
182
183 if (!saved_fp_safe) {
184 return false;
185 }
186
187 // construct the potential sender
188
189 frame sender(sender_sp, saved_fp, sender_pc);
190
191 // Validate the JavaCallWrapper an entry frame must have
192 address jcw = (address)sender.entry_frame_call_wrapper();
193
194 bool jcw_safe = (jcw <= thread->stack_base()) && (jcw > (address)sender.fp());
195
196 return jcw_safe;
197 }
198
199 // If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size
200 // because the return address counts against the callee's frame.
201
202 if (sender_blob->frame_size() <= 0) {
203 assert(!sender_blob->is_compiled(), "should count return address at least");
204 return false;
205 }
206
207 // We should never be able to see anything here except an nmethod. If something in the
208 // code cache (current frame) is called by an entity within the code cache that entity
209 // should not be anything but the call stub (already covered), the interpreter (already covered)
210 // or an nmethod.
211
212 if (!sender_blob->is_compiled()) {
213 return false;
214 }
215
216 // Could put some more validation for the potential non-interpreted sender
217 // frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
218
219 // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
220
221 // We've validated the potential sender that would be created
222 return true;
223 }
224
225 // Must be native-compiled frame. Since sender will try and use fp to find
226 // linkages it must be safe
227
228 if (!fp_safe) {
229 return false;
230 }
231
232 // Will the pc we fetch be non-zero (which we'll find at the oldest frame)
233
234 if ((address) this->fp()[return_addr_offset] == NULL) return false;
235
236
237 // could try and do some more potential verification of native frame if we could think of some...
238
239 return true;
240 }
241
242
243 void frame::patch_pc(Thread* thread, address pc) {
244 address* pc_addr = &((address *)sp())[-sender_sp_offset+return_addr_offset];
245 if (TracePcPatching) {
246 tty->print_cr("patch_pc at address" INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "] ",
247 p2i(pc_addr), p2i(*pc_addr), p2i(pc));
248 }
249 *pc_addr = pc;
250 _cb = CodeCache::find_blob(pc);
251 address original_pc = CompiledMethod::get_deopt_original_pc(this);
252 if (original_pc != NULL) {
253 assert(original_pc == _pc, "expected original PC to be stored before patching");
254 _deopt_state = is_deoptimized;
255 // leave _pc as is
256 } else {
257 _deopt_state = not_deoptimized;
258 _pc = pc;
259 }
260 }
261
262 bool frame::is_interpreted_frame() const {
263 return Interpreter::contains(pc());
264 }
265
266 int frame::frame_size(RegisterMap* map) const {
267 frame sender = this->sender(map);
268 return sender.sp() - sp();
269 }
270
271 intptr_t* frame::entry_frame_argument_at(int offset) const {
272 assert(is_entry_frame(), "entry frame expected");
273 // convert offset to index to deal with tsi
274 int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
275 // Entry frame's arguments are always in relation to unextended_sp()
276 return &unextended_sp()[index];
277 }
278
279 // sender_sp
280 intptr_t* frame::interpreter_frame_sender_sp() const {
281 assert(is_interpreted_frame(), "interpreted frame expected");
282 return (intptr_t*) at(interpreter_frame_sender_sp_offset);
283 }
284
285 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
286 assert(is_interpreted_frame(), "interpreted frame expected");
287 ptr_at_put(interpreter_frame_sender_sp_offset, (intptr_t) sender_sp);
288 }
289
290
291 // monitor elements
292
293 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
294 return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset);
295 }
296
297 BasicObjectLock* frame::interpreter_frame_monitor_end() const {
298 BasicObjectLock* result = (BasicObjectLock*) *addr_at(interpreter_frame_monitor_block_top_offset);
299 // make sure the pointer points inside the frame
300 assert((intptr_t) fp() > (intptr_t) result, "result must < than frame pointer");
301 assert((intptr_t) sp() <= (intptr_t) result, "result must >= than stack pointer");
302 return result;
303 }
304
305 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) {
306 *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value;
307 }
308
309
310 // Used by template based interpreter deoptimization
311 void frame::interpreter_frame_set_last_sp(intptr_t* sp) {
312 *((intptr_t**)addr_at(interpreter_frame_last_sp_offset)) = sp;
313 }
314
315
316 frame frame::sender_for_entry_frame(RegisterMap* map) const {
317 assert(map != NULL, "map must be set");
318 // Java frame called from C; skip all C frames and return top C
319 // frame of that chunk as the sender
320 JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
321 assert(!entry_frame_is_first(), "next Java fp must be non zero");
322 assert(jfa->last_Java_sp() > sp(), "must be above this frame on stack");
323 map->clear();
324 assert(map->include_argument_oops(), "should be set by clear");
325 if (jfa->last_Java_pc() != NULL) {
326 frame fr(jfa->last_Java_sp(), jfa->last_Java_fp(), jfa->last_Java_pc());
327 return fr;
328 }
329 frame fr(jfa->last_Java_sp(), jfa->last_Java_fp());
330 return fr;
331 }
332
333 //------------------------------------------------------------------------------
334 // frame::verify_deopt_original_pc
335 //
336 // Verifies the calculated original PC of a deoptimization PC for the
337 // given unextended SP. The unextended SP might also be the saved SP
338 // for MethodHandle call sites.
339 #ifdef ASSERT
340 void frame::verify_deopt_original_pc(CompiledMethod* nm, intptr_t* unextended_sp, bool is_method_handle_return) {
341 frame fr;
342
343 // This is ugly but it's better than to change {get,set}_original_pc
344 // to take an SP value as argument. And it's only a debugging
345 // method anyway.
346 fr._unextended_sp = unextended_sp;
347
348 address original_pc = nm->get_original_pc(&fr);
349 assert(nm->insts_contains_inclusive(original_pc),
350 "original PC must be in the main code section of the the compiled method (or must be immediately following it)");
351 assert(nm->is_method_handle_return(original_pc) == is_method_handle_return, "must be");
352 }
353 #endif
354
355 //------------------------------------------------------------------------------
356 // frame::adjust_unextended_sp
357 void frame::adjust_unextended_sp() {
358 // same as on x86
359
360 // If we are returning to a compiled MethodHandle call site, the
361 // saved_fp will in fact be a saved value of the unextended SP. The
362 // simplest way to tell whether we are returning to such a call site
363 // is as follows:
364
365 CompiledMethod* sender_cm = (_cb == NULL) ? NULL : _cb->as_compiled_method_or_null();
366 if (sender_cm != NULL) {
367 // If the sender PC is a deoptimization point, get the original
368 // PC. For MethodHandle call site the unextended_sp is stored in
369 // saved_fp.
370 if (sender_cm->is_deopt_mh_entry(_pc)) {
371 DEBUG_ONLY(verify_deopt_mh_original_pc(sender_cm, _fp));
372 _unextended_sp = _fp;
373 }
374 else if (sender_cm->is_deopt_entry(_pc)) {
375 DEBUG_ONLY(verify_deopt_original_pc(sender_cm, _unextended_sp));
376 }
377 else if (sender_cm->is_method_handle_return(_pc)) {
378 _unextended_sp = _fp;
379 }
380 }
381 }
382
383 //------------------------------------------------------------------------------
384 // frame::update_map_with_saved_link
385 void frame::update_map_with_saved_link(RegisterMap* map, intptr_t** link_addr) {
386 // see x86 for comments
387 map->set_location(FP->as_VMReg(), (address) link_addr);
388 }
389
390 frame frame::sender_for_interpreter_frame(RegisterMap* map) const {
391 // SP is the raw SP from the sender after adapter or interpreter
392 // extension.
393 intptr_t* sender_sp = this->sender_sp();
394
395 // This is the sp before any possible extension (adapter/locals).
396 intptr_t* unextended_sp = interpreter_frame_sender_sp();
397
398 #ifdef COMPILER2
399 if (map->update_map()) {
400 update_map_with_saved_link(map, (intptr_t**) addr_at(link_offset));
401 }
402 #endif // COMPILER2
403
404 return frame(sender_sp, unextended_sp, link(), sender_pc());
405 }
406
407 frame frame::sender_for_compiled_frame(RegisterMap* map) const {
408 assert(map != NULL, "map must be set");
409
410 // frame owned by optimizing compiler
411 assert(_cb->frame_size() >= 0, "must have non-zero frame size");
412 intptr_t* sender_sp = unextended_sp() + _cb->frame_size();
413 intptr_t* unextended_sp = sender_sp;
414
415 address sender_pc = (address) *(sender_sp - sender_sp_offset + return_addr_offset);
416
417 // This is the saved value of FP which may or may not really be an FP.
418 // It is only an FP if the sender is an interpreter frame (or C1?).
419 intptr_t** saved_fp_addr = (intptr_t**) (sender_sp - sender_sp_offset + link_offset);
420
421 if (map->update_map()) {
422 // Tell GC to use argument oopmaps for some runtime stubs that need it.
423 // For C1, the runtime stub might not have oop maps, so set this flag
424 // outside of update_register_map.
425 map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
426 if (_cb->oop_maps() != NULL) {
427 OopMapSet::update_register_map(this, map);
428 }
429
430 // Since the prolog does the save and restore of FP there is no oopmap
431 // for it so we must fill in its location as if there was an oopmap entry
432 // since if our caller was compiled code there could be live jvm state in it.
433 update_map_with_saved_link(map, saved_fp_addr);
434 }
435
436 assert(sender_sp != sp(), "must have changed");
437 return frame(sender_sp, unextended_sp, *saved_fp_addr, sender_pc);
438 }
439
440 frame frame::sender(RegisterMap* map) const {
441 // Default is we done have to follow them. The sender_for_xxx will
442 // update it accordingly
443 map->set_include_argument_oops(false);
444
445 if (is_entry_frame()) return sender_for_entry_frame(map);
446 if (is_interpreted_frame()) return sender_for_interpreter_frame(map);
447 assert(_cb == CodeCache::find_blob(pc()),"Must be the same");
448
449 if (_cb != NULL) {
450 return sender_for_compiled_frame(map);
451 }
452
453 assert(false, "should not be called for a C frame");
454 return frame();
455 }
456
457 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
458 assert(is_interpreted_frame(), "Not an interpreted frame");
459 // These are reasonable sanity checks
460 if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
461 return false;
462 }
463 if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
464 return false;
465 }
466 if (fp() + interpreter_frame_initial_sp_offset < sp()) {
467 return false;
468 }
469 // These are hacks to keep us out of trouble.
470 // The problem with these is that they mask other problems
471 if (fp() <= sp()) { // this attempts to deal with unsigned comparison above
472 return false;
473 }
474 // do some validation of frame elements
475
476 // first the method
477
478 Method* m = *interpreter_frame_method_addr();
479
480 // validate the method we'd find in this potential sender
481 if (!Method::is_valid_method(m)) return false;
482
483 // stack frames shouldn't be much larger than max_stack elements
484
485 if (fp() - sp() > 1024 + m->max_stack()*Interpreter::stackElementSize) {
486 return false;
487 }
488
489 // validate bci/bcp
490
491 address bcp = interpreter_frame_bcp();
492 if (m->validate_bci_from_bcp(bcp) < 0) {
493 return false;
494 }
495
496 // validate ConstantPoolCache*
497 ConstantPoolCache* cp = *interpreter_frame_cache_addr();
498 if (MetaspaceObj::is_valid(cp) == false) return false;
499
500 // validate locals
501
502 address locals = (address) *interpreter_frame_locals_addr();
503
504 if (locals > thread->stack_base() || locals < (address) fp()) return false;
505
506 // We'd have to be pretty unlucky to be mislead at this point
507
508 return true;
509 }
510
511 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
512 assert(is_interpreted_frame(), "interpreted frame expected");
513 Method* method = interpreter_frame_method();
514 BasicType type = method->result_type();
515
516 intptr_t* res_addr;
517 if (method->is_native()) {
518 // Prior to calling into the runtime to report the method_exit both of
519 // the possible return value registers are saved.
520 // Return value registers are pushed to the native stack
521 res_addr = (intptr_t*)sp();
522 #ifdef __ABI_HARD__
523 // FP result is pushed onto a stack along with integer result registers
524 if (type == T_FLOAT || type == T_DOUBLE) {
525 res_addr += 2;
526 }
527 #endif // __ABI_HARD__
528 } else {
529 res_addr = (intptr_t*)interpreter_frame_tos_address();
530 }
531
532 switch (type) {
533 case T_OBJECT :
534 case T_ARRAY : {
535 oop obj;
536 if (method->is_native()) {
537 obj = cast_to_oop(at(interpreter_frame_oop_temp_offset));
538 } else {
539 obj = *(oop*)res_addr;
540 }
541 assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
542 *oop_result = obj;
543 break;
544 }
545 case T_BOOLEAN : value_result->z = *(jboolean*)res_addr; break;
546 case T_BYTE : value_result->b = *(jbyte*)res_addr; break;
547 case T_CHAR : value_result->c = *(jchar*)res_addr; break;
548 case T_SHORT : value_result->s = *(jshort*)res_addr; break;
549 case T_INT : value_result->i = *(jint*)res_addr; break;
550 case T_LONG : value_result->j = *(jlong*)res_addr; break;
551 case T_FLOAT : value_result->f = *(jfloat*)res_addr; break;
552 case T_DOUBLE : value_result->d = *(jdouble*)res_addr; break;
553 case T_VOID : /* Nothing to do */ break;
554 default : ShouldNotReachHere();
555 }
556
557 return type;
558 }
559
560
561 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
562 int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
563 return &interpreter_frame_tos_address()[index];
564 }
565
566 #ifndef PRODUCT
567
568 #define DESCRIBE_FP_OFFSET(name) \
569 values.describe(frame_no, fp() + frame::name##_offset, #name)
570
571 void frame::describe_pd(FrameValues& values, int frame_no) {
572 if (is_interpreted_frame()) {
573 DESCRIBE_FP_OFFSET(interpreter_frame_sender_sp);
574 DESCRIBE_FP_OFFSET(interpreter_frame_last_sp);
575 DESCRIBE_FP_OFFSET(interpreter_frame_method);
576 DESCRIBE_FP_OFFSET(interpreter_frame_mdp);
577 DESCRIBE_FP_OFFSET(interpreter_frame_cache);
578 DESCRIBE_FP_OFFSET(interpreter_frame_locals);
579 DESCRIBE_FP_OFFSET(interpreter_frame_bcp);
580 DESCRIBE_FP_OFFSET(interpreter_frame_initial_sp);
581 }
582 }
583
584 // This is a generic constructor which is only used by pns() in debug.cpp.
585 frame::frame(void* sp, void* fp, void* pc) {
586 init((intptr_t*)sp, (intptr_t*)fp, (address)pc);
587 }
588
589 void frame::pd_ps() {}
590 #endif
591
592 intptr_t *frame::initial_deoptimization_info() {
593 // used to reset the saved FP
594 return fp();
595 }
596
597 intptr_t* frame::real_fp() const {
598 if (is_entry_frame()) {
599 // Work-around: FP (currently) does not conform to the ABI for entry
600 // frames (see generate_call_stub). Might be worth fixing as another CR.
601 // Following code assumes (and asserts) this has not yet been fixed.
602 assert(frame::entry_frame_call_wrapper_offset == 0, "adjust this code");
603 intptr_t* new_fp = fp();
604 new_fp += 5; // saved R0,R1,R2,R4,R10
605 #ifndef __SOFTFP__
606 new_fp += 8*2; // saved D8..D15
607 #endif
608 return new_fp;
609 }
610 if (_cb != NULL) {
611 // use the frame size if valid
612 int size = _cb->frame_size();
613 if (size > 0) {
614 return unextended_sp() + size;
615 }
616 }
617 // else rely on fp()
618 assert(! is_compiled_frame(), "unknown compiled frame size");
619 return fp();
620 }