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