1 /*
2 * Copyright (c) 1999, 2025, 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 "asm/codeBuffer.hpp"
26 #include "c1/c1_CodeStubs.hpp"
27 #include "c1/c1_Defs.hpp"
28 #include "c1/c1_LIRAssembler.hpp"
29 #include "c1/c1_MacroAssembler.hpp"
30 #include "c1/c1_Runtime1.hpp"
31 #include "classfile/javaClasses.inline.hpp"
32 #include "classfile/vmClasses.hpp"
33 #include "classfile/vmSymbols.hpp"
34 #include "code/aotCodeCache.hpp"
35 #include "code/codeBlob.hpp"
36 #include "code/compiledIC.hpp"
37 #include "code/scopeDesc.hpp"
38 #include "code/vtableStubs.hpp"
39 #include "compiler/compilationPolicy.hpp"
40 #include "compiler/disassembler.hpp"
41 #include "compiler/oopMap.hpp"
42 #include "gc/shared/barrierSet.hpp"
43 #include "gc/shared/c1/barrierSetC1.hpp"
44 #include "gc/shared/collectedHeap.hpp"
45 #include "interpreter/bytecode.hpp"
46 #include "interpreter/interpreter.hpp"
47 #include "jfr/support/jfrIntrinsics.hpp"
48 #include "logging/log.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "oops/access.inline.hpp"
53 #include "oops/objArrayKlass.hpp"
54 #include "oops/objArrayOop.inline.hpp"
55 #include "oops/oop.inline.hpp"
56 #include "prims/jvmtiExport.hpp"
57 #include "runtime/atomic.hpp"
58 #include "runtime/fieldDescriptor.inline.hpp"
59 #include "runtime/frame.inline.hpp"
60 #include "runtime/handles.inline.hpp"
61 #include "runtime/interfaceSupport.inline.hpp"
62 #include "runtime/javaCalls.hpp"
63 #include "runtime/sharedRuntime.hpp"
64 #include "runtime/stackWatermarkSet.hpp"
65 #include "runtime/stubRoutines.hpp"
66 #include "runtime/vframe.inline.hpp"
67 #include "runtime/vframeArray.hpp"
68 #include "runtime/vm_version.hpp"
69 #include "utilities/copy.hpp"
70 #include "utilities/events.hpp"
71
72
73 // Implementation of StubAssembler
74
75 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
76 _name = name;
77 _must_gc_arguments = false;
78 _frame_size = no_frame_size;
79 _num_rt_args = 0;
80 _stub_id = stub_id;
81 }
82
83
84 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
85 _name = name;
86 _must_gc_arguments = must_gc_arguments;
87 }
88
89
90 void StubAssembler::set_frame_size(int size) {
91 if (_frame_size == no_frame_size) {
92 _frame_size = size;
93 }
94 assert(_frame_size == size, "can't change the frame size");
95 }
96
97
98 void StubAssembler::set_num_rt_args(int args) {
99 if (_num_rt_args == 0) {
100 _num_rt_args = args;
101 }
102 assert(_num_rt_args == args, "can't change the number of args");
103 }
104
105 // Implementation of Runtime1
106
107 CodeBlob* Runtime1::_blobs[(int)C1StubId::NUM_STUBIDS];
108
109 #define C1_BLOB_NAME_DEFINE(name) "C1 Runtime " # name "_blob",
110 const char *Runtime1::_blob_names[] = {
111 C1_STUBS_DO(C1_BLOB_NAME_DEFINE)
112 };
113 #undef C1_STUB_NAME_DEFINE
114
115 #ifndef PRODUCT
116 // statistics
117 uint Runtime1::_generic_arraycopystub_cnt = 0;
118 uint Runtime1::_arraycopy_slowcase_cnt = 0;
119 uint Runtime1::_arraycopy_checkcast_cnt = 0;
120 uint Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
121 uint Runtime1::_new_type_array_slowcase_cnt = 0;
122 uint Runtime1::_new_object_array_slowcase_cnt = 0;
123 uint Runtime1::_new_instance_slowcase_cnt = 0;
124 uint Runtime1::_new_multi_array_slowcase_cnt = 0;
125 uint Runtime1::_monitorenter_slowcase_cnt = 0;
126 uint Runtime1::_monitorexit_slowcase_cnt = 0;
127 uint Runtime1::_patch_code_slowcase_cnt = 0;
128 uint Runtime1::_throw_range_check_exception_count = 0;
129 uint Runtime1::_throw_index_exception_count = 0;
130 uint Runtime1::_throw_div0_exception_count = 0;
131 uint Runtime1::_throw_null_pointer_exception_count = 0;
132 uint Runtime1::_throw_class_cast_exception_count = 0;
133 uint Runtime1::_throw_incompatible_class_change_error_count = 0;
134 uint Runtime1::_throw_count = 0;
135
136 static uint _byte_arraycopy_stub_cnt = 0;
137 static uint _short_arraycopy_stub_cnt = 0;
138 static uint _int_arraycopy_stub_cnt = 0;
139 static uint _long_arraycopy_stub_cnt = 0;
140 static uint _oop_arraycopy_stub_cnt = 0;
141
142 address Runtime1::arraycopy_count_address(BasicType type) {
143 switch (type) {
144 case T_BOOLEAN:
145 case T_BYTE: return (address)&_byte_arraycopy_stub_cnt;
146 case T_CHAR:
147 case T_SHORT: return (address)&_short_arraycopy_stub_cnt;
148 case T_FLOAT:
149 case T_INT: return (address)&_int_arraycopy_stub_cnt;
150 case T_DOUBLE:
151 case T_LONG: return (address)&_long_arraycopy_stub_cnt;
152 case T_ARRAY:
153 case T_OBJECT: return (address)&_oop_arraycopy_stub_cnt;
154 default:
155 ShouldNotReachHere();
156 return nullptr;
157 }
158 }
159
160
161 #endif
162
163 // Simple helper to see if the caller of a runtime stub which
164 // entered the VM has been deoptimized
165
166 static bool caller_is_deopted(JavaThread* current) {
167 RegisterMap reg_map(current,
168 RegisterMap::UpdateMap::skip,
169 RegisterMap::ProcessFrames::include,
170 RegisterMap::WalkContinuation::skip);
171 frame runtime_frame = current->last_frame();
172 frame caller_frame = runtime_frame.sender(®_map);
173 assert(caller_frame.is_compiled_frame(), "must be compiled");
174 return caller_frame.is_deoptimized_frame();
175 }
176
177 // Stress deoptimization
178 static void deopt_caller(JavaThread* current) {
179 if (!caller_is_deopted(current)) {
180 RegisterMap reg_map(current,
181 RegisterMap::UpdateMap::skip,
182 RegisterMap::ProcessFrames::include,
183 RegisterMap::WalkContinuation::skip);
184 frame runtime_frame = current->last_frame();
185 frame caller_frame = runtime_frame.sender(®_map);
186 Deoptimization::deoptimize_frame(current, caller_frame.id());
187 assert(caller_is_deopted(current), "Must be deoptimized");
188 }
189 }
190
191 class C1StubIdStubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
192 private:
193 C1StubId _id;
194 public:
195 C1StubIdStubAssemblerCodeGenClosure(C1StubId id) : _id(id) {}
196 virtual OopMapSet* generate_code(StubAssembler* sasm) {
197 return Runtime1::generate_code_for(_id, sasm);
198 }
199 };
200
201 CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, C1StubId id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
202 if ((int)id >= 0) {
203 CodeBlob* blob = AOTCodeCache::load_code_blob(AOTCodeEntry::C1Blob, (uint)id, name, 0, nullptr);
204 if (blob != nullptr) {
205 return blob;
206 }
207 }
208
209 ResourceMark rm;
210 // create code buffer for code storage
211 CodeBuffer code(buffer_blob);
212
213 OopMapSet* oop_maps;
214 int frame_size;
215 bool must_gc_arguments;
216
217 Compilation::setup_code_buffer(&code, 0);
218
219 // create assembler for code generation
220 StubAssembler* sasm = new StubAssembler(&code, name, (int)id);
221 // generate code for runtime stub
222 oop_maps = cl->generate_code(sasm);
223 assert(oop_maps == nullptr || sasm->frame_size() != no_frame_size,
224 "if stub has an oop map it must have a valid frame size");
225 assert(!expect_oop_map || oop_maps != nullptr, "must have an oopmap");
226
227 // align so printing shows nop's instead of random code at the end (SimpleStubs are aligned)
228 sasm->align(BytesPerWord);
229 // make sure all code is in code buffer
230 sasm->flush();
231
232 frame_size = sasm->frame_size();
233 must_gc_arguments = sasm->must_gc_arguments();
234 // create blob - distinguish a few special cases
235 CodeBlob* blob = RuntimeStub::new_runtime_stub(name,
236 &code,
237 CodeOffsets::frame_never_safe,
238 frame_size,
239 oop_maps,
240 must_gc_arguments,
241 false /* alloc_fail_is_fatal */ );
242 if (blob != nullptr && (int)id >= 0) {
243 AOTCodeCache::store_code_blob(*blob, AOTCodeEntry::C1Blob, (uint)id, name, 0, nullptr);
244 }
245 return blob;
246 }
247
248 bool Runtime1::generate_blob_for(BufferBlob* buffer_blob, C1StubId id) {
249 assert(C1StubId::NO_STUBID < id && id < C1StubId::NUM_STUBIDS, "illegal stub id");
250 bool expect_oop_map = true;
251 #ifdef ASSERT
252 // Make sure that stubs that need oopmaps have them
253 switch (id) {
254 // These stubs don't need to have an oopmap
255 case C1StubId::dtrace_object_alloc_id:
256 case C1StubId::slow_subtype_check_id:
257 case C1StubId::fpu2long_stub_id:
258 case C1StubId::unwind_exception_id:
259 case C1StubId::counter_overflow_id:
260 case C1StubId::is_instance_of_id:
261 expect_oop_map = false;
262 break;
263 default:
264 break;
265 }
266 #endif
267 C1StubIdStubAssemblerCodeGenClosure cl(id);
268 CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
269 // install blob
270 _blobs[(int)id] = blob;
271 return blob != nullptr;
272 }
273
274 bool Runtime1::initialize(BufferBlob* blob) {
275 // platform-dependent initialization
276 initialize_pd();
277 // generate stubs
278 int limit = (int)C1StubId::NUM_STUBIDS;
279 for (int id = 0; id <= (int)C1StubId::forward_exception_id; id++) {
280 if (!generate_blob_for(blob, (C1StubId) id)) {
281 return false;
282 }
283 }
284 AOTCodeCache::init_early_c1_table();
285 for (int id = (int)C1StubId::forward_exception_id+1; id < limit; id++) {
286 if (!generate_blob_for(blob, (C1StubId) id)) {
287 return false;
288 }
289 }
290 // printing
291 #ifndef PRODUCT
292 if (PrintSimpleStubs) {
293 ResourceMark rm;
294 for (int id = 0; id < limit; id++) {
295 _blobs[id]->print();
296 if (_blobs[id]->oop_maps() != nullptr) {
297 _blobs[id]->oop_maps()->print();
298 }
299 }
300 }
301 #endif
302 BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
303 return bs->generate_c1_runtime_stubs(blob);
304 }
305
306 CodeBlob* Runtime1::blob_for(C1StubId id) {
307 assert(C1StubId::NO_STUBID < id && id < C1StubId::NUM_STUBIDS, "illegal stub id");
308 return _blobs[(int)id];
309 }
310
311
312 const char* Runtime1::name_for(C1StubId id) {
313 assert(C1StubId::NO_STUBID < id && id < C1StubId::NUM_STUBIDS, "illegal stub id");
314 return _blob_names[(int)id];
315 }
316
317 const char* Runtime1::name_for_address(address entry) {
318 int limit = (int)C1StubId::NUM_STUBIDS;
319 for (int i = 0; i < limit; i++) {
320 C1StubId id = (C1StubId)i;
321 if (entry == entry_for(id)) return name_for(id);
322 }
323
324 #define FUNCTION_CASE(a, f) \
325 if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f)) return #f
326
327 FUNCTION_CASE(entry, os::javaTimeMillis);
328 FUNCTION_CASE(entry, os::javaTimeNanos);
329 FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
330 FUNCTION_CASE(entry, SharedRuntime::d2f);
331 FUNCTION_CASE(entry, SharedRuntime::d2i);
332 FUNCTION_CASE(entry, SharedRuntime::d2l);
333 FUNCTION_CASE(entry, SharedRuntime::dcos);
334 FUNCTION_CASE(entry, SharedRuntime::dexp);
335 FUNCTION_CASE(entry, SharedRuntime::dlog);
336 FUNCTION_CASE(entry, SharedRuntime::dlog10);
337 FUNCTION_CASE(entry, SharedRuntime::dpow);
338 FUNCTION_CASE(entry, SharedRuntime::drem);
339 FUNCTION_CASE(entry, SharedRuntime::dsin);
340 FUNCTION_CASE(entry, SharedRuntime::dtan);
341 FUNCTION_CASE(entry, SharedRuntime::f2i);
342 FUNCTION_CASE(entry, SharedRuntime::f2l);
343 FUNCTION_CASE(entry, SharedRuntime::frem);
344 FUNCTION_CASE(entry, SharedRuntime::l2d);
345 FUNCTION_CASE(entry, SharedRuntime::l2f);
346 FUNCTION_CASE(entry, SharedRuntime::ldiv);
347 FUNCTION_CASE(entry, SharedRuntime::lmul);
348 FUNCTION_CASE(entry, SharedRuntime::lrem);
349 FUNCTION_CASE(entry, SharedRuntime::lrem);
350 FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
351 FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
352 FUNCTION_CASE(entry, is_instance_of);
353 FUNCTION_CASE(entry, trace_block_entry);
354 #ifdef JFR_HAVE_INTRINSICS
355 FUNCTION_CASE(entry, JfrTime::time_function());
356 #endif
357 FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
358 FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
359 FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
360 FUNCTION_CASE(entry, StubRoutines::dexp());
361 FUNCTION_CASE(entry, StubRoutines::dlog());
362 FUNCTION_CASE(entry, StubRoutines::dlog10());
363 FUNCTION_CASE(entry, StubRoutines::dpow());
364 FUNCTION_CASE(entry, StubRoutines::dsin());
365 FUNCTION_CASE(entry, StubRoutines::dcos());
366 FUNCTION_CASE(entry, StubRoutines::dtan());
367 FUNCTION_CASE(entry, StubRoutines::dtanh());
368 FUNCTION_CASE(entry, StubRoutines::dcbrt());
369
370 #undef FUNCTION_CASE
371
372 // Soft float adds more runtime names.
373 return pd_name_for_address(entry);
374 }
375
376
377 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* current, Klass* klass))
378 #ifndef PRODUCT
379 if (PrintC1Statistics) {
380 _new_instance_slowcase_cnt++;
381 }
382 #endif
383 assert(klass->is_klass(), "not a class");
384 Handle holder(current, klass->klass_holder()); // keep the klass alive
385 InstanceKlass* h = InstanceKlass::cast(klass);
386 h->check_valid_for_instantiation(true, CHECK);
387 // make sure klass is initialized
388 h->initialize(CHECK);
389 // allocate instance and return via TLS
390 oop obj = h->allocate_instance(CHECK);
391 current->set_vm_result_oop(obj);
392 JRT_END
393
394
395 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* current, Klass* klass, jint length))
396 #ifndef PRODUCT
397 if (PrintC1Statistics) {
398 _new_type_array_slowcase_cnt++;
399 }
400 #endif
401 // Note: no handle for klass needed since they are not used
402 // anymore after new_typeArray() and no GC can happen before.
403 // (This may have to change if this code changes!)
404 assert(klass->is_klass(), "not a class");
405 BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
406 oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
407 current->set_vm_result_oop(obj);
408 // This is pretty rare but this runtime patch is stressful to deoptimization
409 // if we deoptimize here so force a deopt to stress the path.
410 if (DeoptimizeALot) {
411 deopt_caller(current);
412 }
413
414 JRT_END
415
416
417 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* current, Klass* array_klass, jint length))
418 #ifndef PRODUCT
419 if (PrintC1Statistics) {
420 _new_object_array_slowcase_cnt++;
421 }
422 #endif
423 // Note: no handle for klass needed since they are not used
424 // anymore after new_objArray() and no GC can happen before.
425 // (This may have to change if this code changes!)
426 assert(array_klass->is_klass(), "not a class");
427 Handle holder(current, array_klass->klass_holder()); // keep the klass alive
428 Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
429 objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
430 current->set_vm_result_oop(obj);
431 // This is pretty rare but this runtime patch is stressful to deoptimization
432 // if we deoptimize here so force a deopt to stress the path.
433 if (DeoptimizeALot) {
434 deopt_caller(current);
435 }
436 JRT_END
437
438
439 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* current, Klass* klass, int rank, jint* dims))
440 #ifndef PRODUCT
441 if (PrintC1Statistics) {
442 _new_multi_array_slowcase_cnt++;
443 }
444 #endif
445 assert(klass->is_klass(), "not a class");
446 assert(rank >= 1, "rank must be nonzero");
447 Handle holder(current, klass->klass_holder()); // keep the klass alive
448 oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
449 current->set_vm_result_oop(obj);
450 JRT_END
451
452
453 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* current, C1StubId id))
454 tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", (int)id);
455 JRT_END
456
457
458 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* current, oopDesc* obj))
459 ResourceMark rm(current);
460 const char* klass_name = obj->klass()->external_name();
461 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayStoreException(), klass_name);
462 JRT_END
463
464
465 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
466 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
467 // method) method is passed as an argument. In order to do that it is embedded in the code as
468 // a constant.
469 static nmethod* counter_overflow_helper(JavaThread* current, int branch_bci, Method* m) {
470 nmethod* osr_nm = nullptr;
471 methodHandle method(current, m);
472
473 RegisterMap map(current,
474 RegisterMap::UpdateMap::skip,
475 RegisterMap::ProcessFrames::include,
476 RegisterMap::WalkContinuation::skip);
477 frame fr = current->last_frame().sender(&map);
478 nmethod* nm = (nmethod*) fr.cb();
479 assert(nm!= nullptr && nm->is_nmethod(), "Sanity check");
480 methodHandle enclosing_method(current, nm->method());
481
482 CompLevel level = (CompLevel)nm->comp_level();
483 int bci = InvocationEntryBci;
484 if (branch_bci != InvocationEntryBci) {
485 // Compute destination bci
486 address pc = method()->code_base() + branch_bci;
487 Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
488 int offset = 0;
489 switch (branch) {
490 case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
491 case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
492 case Bytecodes::_if_icmple: case Bytecodes::_ifle:
493 case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
494 case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
495 case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
496 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
497 offset = (int16_t)Bytes::get_Java_u2(pc + 1);
498 break;
499 case Bytecodes::_goto_w:
500 offset = Bytes::get_Java_u4(pc + 1);
501 break;
502 default: ;
503 }
504 bci = branch_bci + offset;
505 }
506 osr_nm = CompilationPolicy::event(enclosing_method, method, branch_bci, bci, level, nm, current);
507 return osr_nm;
508 }
509
510 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* current, int bci, Method* method))
511 nmethod* osr_nm;
512 JRT_BLOCK_NO_ASYNC
513 osr_nm = counter_overflow_helper(current, bci, method);
514 if (osr_nm != nullptr) {
515 RegisterMap map(current,
516 RegisterMap::UpdateMap::skip,
517 RegisterMap::ProcessFrames::include,
518 RegisterMap::WalkContinuation::skip);
519 frame fr = current->last_frame().sender(&map);
520 Deoptimization::deoptimize_frame(current, fr.id());
521 }
522 JRT_BLOCK_END
523 return nullptr;
524 JRT_END
525
526 extern void vm_exit(int code);
527
528 // Enter this method from compiled code handler below. This is where we transition
529 // to VM mode. This is done as a helper routine so that the method called directly
530 // from compiled code does not have to transition to VM. This allows the entry
531 // method to see if the nmethod that we have just looked up a handler for has
532 // been deoptimized while we were in the vm. This simplifies the assembly code
533 // cpu directories.
534 //
535 // We are entering here from exception stub (via the entry method below)
536 // If there is a compiled exception handler in this method, we will continue there;
537 // otherwise we will unwind the stack and continue at the caller of top frame method
538 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
539 // control the area where we can allow a safepoint. After we exit the safepoint area we can
540 // check to see if the handler we are going to return is now in a nmethod that has
541 // been deoptimized. If that is the case we return the deopt blob
542 // unpack_with_exception entry instead. This makes life for the exception blob easier
543 // because making that same check and diverting is painful from assembly language.
544 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* current, oopDesc* ex, address pc, nmethod*& nm))
545 // Reset method handle flag.
546 current->set_is_method_handle_return(false);
547
548 Handle exception(current, ex);
549
550 // This function is called when we are about to throw an exception. Therefore,
551 // we have to poll the stack watermark barrier to make sure that not yet safe
552 // stack frames are made safe before returning into them.
553 if (current->last_frame().cb() == Runtime1::blob_for(C1StubId::handle_exception_from_callee_id)) {
554 // The C1StubId::handle_exception_from_callee_id handler is invoked after the
555 // frame has been unwound. It instead builds its own stub frame, to call the
556 // runtime. But the throwing frame has already been unwound here.
557 StackWatermarkSet::after_unwind(current);
558 }
559
560 nm = CodeCache::find_nmethod(pc);
561 assert(nm != nullptr, "this is not an nmethod");
562 // Adjust the pc as needed/
563 if (nm->is_deopt_pc(pc)) {
564 RegisterMap map(current,
565 RegisterMap::UpdateMap::skip,
566 RegisterMap::ProcessFrames::include,
567 RegisterMap::WalkContinuation::skip);
568 frame exception_frame = current->last_frame().sender(&map);
569 // if the frame isn't deopted then pc must not correspond to the caller of last_frame
570 assert(exception_frame.is_deoptimized_frame(), "must be deopted");
571 pc = exception_frame.pc();
572 }
573 assert(exception.not_null(), "null exceptions should be handled by throw_exception");
574 // Check that exception is a subclass of Throwable
575 assert(exception->is_a(vmClasses::Throwable_klass()),
576 "Exception not subclass of Throwable");
577
578 // debugging support
579 // tracing
580 if (log_is_enabled(Info, exceptions)) {
581 ResourceMark rm; // print_value_string
582 stringStream tempst;
583 assert(nm->method() != nullptr, "Unexpected null method()");
584 tempst.print("C1 compiled method <%s>\n"
585 " at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
586 nm->method()->print_value_string(), p2i(pc), p2i(current));
587 Exceptions::log_exception(exception, tempst.freeze());
588 }
589 // for AbortVMOnException flag
590 Exceptions::debug_check_abort(exception);
591
592 // Check the stack guard pages and re-enable them if necessary and there is
593 // enough space on the stack to do so. Use fast exceptions only if the guard
594 // pages are enabled.
595 bool guard_pages_enabled = current->stack_overflow_state()->reguard_stack_if_needed();
596
597 if (JvmtiExport::can_post_on_exceptions()) {
598 // To ensure correct notification of exception catches and throws
599 // we have to deoptimize here. If we attempted to notify the
600 // catches and throws during this exception lookup it's possible
601 // we could deoptimize on the way out of the VM and end back in
602 // the interpreter at the throw site. This would result in double
603 // notifications since the interpreter would also notify about
604 // these same catches and throws as it unwound the frame.
605
606 RegisterMap reg_map(current,
607 RegisterMap::UpdateMap::include,
608 RegisterMap::ProcessFrames::include,
609 RegisterMap::WalkContinuation::skip);
610 frame stub_frame = current->last_frame();
611 frame caller_frame = stub_frame.sender(®_map);
612
613 // We don't really want to deoptimize the nmethod itself since we
614 // can actually continue in the exception handler ourselves but I
615 // don't see an easy way to have the desired effect.
616 Deoptimization::deoptimize_frame(current, caller_frame.id());
617 assert(caller_is_deopted(current), "Must be deoptimized");
618
619 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
620 }
621
622 // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
623 if (guard_pages_enabled) {
624 address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
625 if (fast_continuation != nullptr) {
626 // Set flag if return address is a method handle call site.
627 current->set_is_method_handle_return(nm->is_method_handle_return(pc));
628 return fast_continuation;
629 }
630 }
631
632 // If the stack guard pages are enabled, check whether there is a handler in
633 // the current method. Otherwise (guard pages disabled), force an unwind and
634 // skip the exception cache update (i.e., just leave continuation as null).
635 address continuation = nullptr;
636 if (guard_pages_enabled) {
637
638 // New exception handling mechanism can support inlined methods
639 // with exception handlers since the mappings are from PC to PC
640
641 // Clear out the exception oop and pc since looking up an
642 // exception handler can cause class loading, which might throw an
643 // exception and those fields are expected to be clear during
644 // normal bytecode execution.
645 current->clear_exception_oop_and_pc();
646
647 bool recursive_exception = false;
648 continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
649 // If an exception was thrown during exception dispatch, the exception oop may have changed
650 current->set_exception_oop(exception());
651 current->set_exception_pc(pc);
652
653 // the exception cache is used only by non-implicit exceptions
654 // Update the exception cache only when there didn't happen
655 // another exception during the computation of the compiled
656 // exception handler. Checking for exception oop equality is not
657 // sufficient because some exceptions are pre-allocated and reused.
658 if (continuation != nullptr && !recursive_exception) {
659 nm->add_handler_for_exception_and_pc(exception, pc, continuation);
660 }
661 }
662
663 current->set_vm_result_oop(exception());
664 // Set flag if return address is a method handle call site.
665 current->set_is_method_handle_return(nm->is_method_handle_return(pc));
666
667 if (log_is_enabled(Info, exceptions)) {
668 ResourceMark rm;
669 log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
670 " for exception thrown at PC " PTR_FORMAT,
671 p2i(current), p2i(continuation), p2i(pc));
672 }
673
674 return continuation;
675 JRT_END
676
677 // Enter this method from compiled code only if there is a Java exception handler
678 // in the method handling the exception.
679 // We are entering here from exception stub. We don't do a normal VM transition here.
680 // We do it in a helper. This is so we can check to see if the nmethod we have just
681 // searched for an exception handler has been deoptimized in the meantime.
682 address Runtime1::exception_handler_for_pc(JavaThread* current) {
683 oop exception = current->exception_oop();
684 address pc = current->exception_pc();
685 // Still in Java mode
686 DEBUG_ONLY(NoHandleMark nhm);
687 nmethod* nm = nullptr;
688 address continuation = nullptr;
689 {
690 // Enter VM mode by calling the helper
691 ResetNoHandleMark rnhm;
692 continuation = exception_handler_for_pc_helper(current, exception, pc, nm);
693 }
694 // Back in JAVA, use no oops DON'T safepoint
695
696 // Now check to see if the nmethod we were called from is now deoptimized.
697 // If so we must return to the deopt blob and deoptimize the nmethod
698 if (nm != nullptr && caller_is_deopted(current)) {
699 continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
700 }
701
702 assert(continuation != nullptr, "no handler found");
703 return continuation;
704 }
705
706
707 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* current, int index, arrayOopDesc* a))
708 #ifndef PRODUCT
709 if (PrintC1Statistics) {
710 _throw_range_check_exception_count++;
711 }
712 #endif
713 const int len = 35;
714 assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
715 char message[2 * jintAsStringSize + len];
716 os::snprintf_checked(message, sizeof(message), "Index %d out of bounds for length %d", index, a->length());
717 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
718 JRT_END
719
720
721 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* current, int index))
722 #ifndef PRODUCT
723 if (PrintC1Statistics) {
724 _throw_index_exception_count++;
725 }
726 #endif
727 char message[16];
728 os::snprintf_checked(message, sizeof(message), "%d", index);
729 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
730 JRT_END
731
732
733 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* current))
734 #ifndef PRODUCT
735 if (PrintC1Statistics) {
736 _throw_div0_exception_count++;
737 }
738 #endif
739 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
740 JRT_END
741
742
743 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* current))
744 #ifndef PRODUCT
745 if (PrintC1Statistics) {
746 _throw_null_pointer_exception_count++;
747 }
748 #endif
749 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_NullPointerException());
750 JRT_END
751
752
753 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* current, oopDesc* object))
754 #ifndef PRODUCT
755 if (PrintC1Statistics) {
756 _throw_class_cast_exception_count++;
757 }
758 #endif
759 ResourceMark rm(current);
760 char* message = SharedRuntime::generate_class_cast_message(current, object->klass());
761 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ClassCastException(), message);
762 JRT_END
763
764
765 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* current))
766 #ifndef PRODUCT
767 if (PrintC1Statistics) {
768 _throw_incompatible_class_change_error_count++;
769 }
770 #endif
771 ResourceMark rm(current);
772 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IncompatibleClassChangeError());
773 JRT_END
774
775
776 JRT_BLOCK_ENTRY(void, Runtime1::monitorenter(JavaThread* current, oopDesc* obj, BasicObjectLock* lock))
777 #ifndef PRODUCT
778 if (PrintC1Statistics) {
779 _monitorenter_slowcase_cnt++;
780 }
781 #endif
782 if (LockingMode == LM_MONITOR) {
783 lock->set_obj(obj);
784 }
785 assert(obj == lock->obj(), "must match");
786 SharedRuntime::monitor_enter_helper(obj, lock->lock(), current);
787 JRT_END
788
789
790 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* current, BasicObjectLock* lock))
791 assert(current == JavaThread::current(), "pre-condition");
792 #ifndef PRODUCT
793 if (PrintC1Statistics) {
794 _monitorexit_slowcase_cnt++;
795 }
796 #endif
797 assert(current->last_Java_sp(), "last_Java_sp must be set");
798 oop obj = lock->obj();
799 assert(oopDesc::is_oop(obj), "must be null or an object");
800 SharedRuntime::monitor_exit_helper(obj, lock->lock(), current);
801 JRT_END
802
803 // Cf. OptoRuntime::deoptimize_caller_frame
804 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* current, jint trap_request))
805 // Called from within the owner thread, so no need for safepoint
806 RegisterMap reg_map(current,
807 RegisterMap::UpdateMap::skip,
808 RegisterMap::ProcessFrames::include,
809 RegisterMap::WalkContinuation::skip);
810 frame stub_frame = current->last_frame();
811 assert(stub_frame.is_runtime_frame(), "Sanity check");
812 frame caller_frame = stub_frame.sender(®_map);
813 nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
814 assert(nm != nullptr, "Sanity check");
815 methodHandle method(current, nm->method());
816 assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
817 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
818 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
819
820 if (action == Deoptimization::Action_make_not_entrant) {
821 if (nm->make_not_entrant("C1 deoptimize")) {
822 if (reason == Deoptimization::Reason_tenured) {
823 MethodData* trap_mdo = Deoptimization::get_method_data(current, method, true /*create_if_missing*/);
824 if (trap_mdo != nullptr) {
825 trap_mdo->inc_tenure_traps();
826 }
827 }
828 }
829 }
830
831 // Deoptimize the caller frame.
832 Deoptimization::deoptimize_frame(current, caller_frame.id());
833 // Return to the now deoptimized frame.
834 JRT_END
835
836
837 #ifndef DEOPTIMIZE_WHEN_PATCHING
838
839 static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
840 Bytecode_field field_access(caller, bci);
841 // This can be static or non-static field access
842 Bytecodes::Code code = field_access.code();
843
844 // We must load class, initialize class and resolve the field
845 fieldDescriptor result; // initialize class if needed
846 constantPoolHandle constants(THREAD, caller->constants());
847 LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
848 return result.field_holder();
849 }
850
851
852 //
853 // This routine patches sites where a class wasn't loaded or
854 // initialized at the time the code was generated. It handles
855 // references to classes, fields and forcing of initialization. Most
856 // of the cases are straightforward and involving simply forcing
857 // resolution of a class, rewriting the instruction stream with the
858 // needed constant and replacing the call in this function with the
859 // patched code. The case for static field is more complicated since
860 // the thread which is in the process of initializing a class can
861 // access it's static fields but other threads can't so the code
862 // either has to deoptimize when this case is detected or execute a
863 // check that the current thread is the initializing thread. The
864 // current
865 //
866 // Patches basically look like this:
867 //
868 //
869 // patch_site: jmp patch stub ;; will be patched
870 // continue: ...
871 // ...
872 // ...
873 // ...
874 //
875 // They have a stub which looks like this:
876 //
877 // ;; patch body
878 // movl <const>, reg (for class constants)
879 // <or> movl [reg1 + <const>], reg (for field offsets)
880 // <or> movl reg, [reg1 + <const>] (for field offsets)
881 // <being_init offset> <bytes to copy> <bytes to skip>
882 // patch_stub: call Runtime1::patch_code (through a runtime stub)
883 // jmp patch_site
884 //
885 //
886 // A normal patch is done by rewriting the patch body, usually a move,
887 // and then copying it into place over top of the jmp instruction
888 // being careful to flush caches and doing it in an MP-safe way. The
889 // constants following the patch body are used to find various pieces
890 // of the patch relative to the call site for Runtime1::patch_code.
891 // The case for getstatic and putstatic is more complicated because
892 // getstatic and putstatic have special semantics when executing while
893 // the class is being initialized. getstatic/putstatic on a class
894 // which is being_initialized may be executed by the initializing
895 // thread but other threads have to block when they execute it. This
896 // is accomplished in compiled code by executing a test of the current
897 // thread against the initializing thread of the class. It's emitted
898 // as boilerplate in their stub which allows the patched code to be
899 // executed before it's copied back into the main body of the nmethod.
900 //
901 // being_init: get_thread(<tmp reg>
902 // cmpl [reg1 + <init_thread_offset>], <tmp reg>
903 // jne patch_stub
904 // movl [reg1 + <const>], reg (for field offsets) <or>
905 // movl reg, [reg1 + <const>] (for field offsets)
906 // jmp continue
907 // <being_init offset> <bytes to copy> <bytes to skip>
908 // patch_stub: jmp Runtime1::patch_code (through a runtime stub)
909 // jmp patch_site
910 //
911 // If the class is being initialized the patch body is rewritten and
912 // the patch site is rewritten to jump to being_init, instead of
913 // patch_stub. Whenever this code is executed it checks the current
914 // thread against the initializing thread so other threads will enter
915 // the runtime and end up blocked waiting the class to finish
916 // initializing inside the calls to resolve_field below. The
917 // initializing class will continue on it's way. Once the class is
918 // fully_initialized, the intializing_thread of the class becomes
919 // null, so the next thread to execute this code will fail the test,
920 // call into patch_code and complete the patching process by copying
921 // the patch body back into the main part of the nmethod and resume
922 // executing.
923
924 // NB:
925 //
926 // Patchable instruction sequences inherently exhibit race conditions,
927 // where thread A is patching an instruction at the same time thread B
928 // is executing it. The algorithms we use ensure that any observation
929 // that B can make on any intermediate states during A's patching will
930 // always end up with a correct outcome. This is easiest if there are
931 // few or no intermediate states. (Some inline caches have two
932 // related instructions that must be patched in tandem. For those,
933 // intermediate states seem to be unavoidable, but we will get the
934 // right answer from all possible observation orders.)
935 //
936 // When patching the entry instruction at the head of a method, or a
937 // linkable call instruction inside of a method, we try very hard to
938 // use a patch sequence which executes as a single memory transaction.
939 // This means, in practice, that when thread A patches an instruction,
940 // it should patch a 32-bit or 64-bit word that somehow overlaps the
941 // instruction or is contained in it. We believe that memory hardware
942 // will never break up such a word write, if it is naturally aligned
943 // for the word being written. We also know that some CPUs work very
944 // hard to create atomic updates even of naturally unaligned words,
945 // but we don't want to bet the farm on this always working.
946 //
947 // Therefore, if there is any chance of a race condition, we try to
948 // patch only naturally aligned words, as single, full-word writes.
949
950 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* current, C1StubId stub_id ))
951 #ifndef PRODUCT
952 if (PrintC1Statistics) {
953 _patch_code_slowcase_cnt++;
954 }
955 #endif
956
957 ResourceMark rm(current);
958 RegisterMap reg_map(current,
959 RegisterMap::UpdateMap::skip,
960 RegisterMap::ProcessFrames::include,
961 RegisterMap::WalkContinuation::skip);
962 frame runtime_frame = current->last_frame();
963 frame caller_frame = runtime_frame.sender(®_map);
964
965 // last java frame on stack
966 vframeStream vfst(current, true);
967 assert(!vfst.at_end(), "Java frame must exist");
968
969 methodHandle caller_method(current, vfst.method());
970 // Note that caller_method->code() may not be same as caller_code because of OSR's
971 // Note also that in the presence of inlining it is not guaranteed
972 // that caller_method() == caller_code->method()
973
974 int bci = vfst.bci();
975 Bytecodes::Code code = caller_method()->java_code_at(bci);
976
977 // this is used by assertions in the access_field_patching_id
978 BasicType patch_field_type = T_ILLEGAL;
979 bool deoptimize_for_volatile = false;
980 bool deoptimize_for_atomic = false;
981 int patch_field_offset = -1;
982 Klass* init_klass = nullptr; // klass needed by load_klass_patching code
983 Klass* load_klass = nullptr; // klass needed by load_klass_patching code
984 Handle mirror(current, nullptr); // oop needed by load_mirror_patching code
985 Handle appendix(current, nullptr); // oop needed by appendix_patching code
986 bool load_klass_or_mirror_patch_id =
987 (stub_id == C1StubId::load_klass_patching_id || stub_id == C1StubId::load_mirror_patching_id);
988
989 if (stub_id == C1StubId::access_field_patching_id) {
990
991 Bytecode_field field_access(caller_method, bci);
992 fieldDescriptor result; // initialize class if needed
993 Bytecodes::Code code = field_access.code();
994 constantPoolHandle constants(current, caller_method->constants());
995 LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
996 patch_field_offset = result.offset();
997
998 // If we're patching a field which is volatile then at compile it
999 // must not have been know to be volatile, so the generated code
1000 // isn't correct for a volatile reference. The nmethod has to be
1001 // deoptimized so that the code can be regenerated correctly.
1002 // This check is only needed for access_field_patching since this
1003 // is the path for patching field offsets. load_klass is only
1004 // used for patching references to oops which don't need special
1005 // handling in the volatile case.
1006
1007 deoptimize_for_volatile = result.access_flags().is_volatile();
1008
1009 // If we are patching a field which should be atomic, then
1010 // the generated code is not correct either, force deoptimizing.
1011 // We need to only cover T_LONG and T_DOUBLE fields, as we can
1012 // break access atomicity only for them.
1013
1014 // Strictly speaking, the deoptimization on 64-bit platforms
1015 // is unnecessary, and T_LONG stores on 32-bit platforms need
1016 // to be handled by special patching code when AlwaysAtomicAccesses
1017 // becomes product feature. At this point, we are still going
1018 // for the deoptimization for consistency against volatile
1019 // accesses.
1020
1021 patch_field_type = result.field_type();
1022 deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
1023
1024 } else if (load_klass_or_mirror_patch_id) {
1025 Klass* k = nullptr;
1026 switch (code) {
1027 case Bytecodes::_putstatic:
1028 case Bytecodes::_getstatic:
1029 { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
1030 init_klass = klass;
1031 mirror = Handle(current, klass->java_mirror());
1032 }
1033 break;
1034 case Bytecodes::_new:
1035 { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
1036 k = caller_method->constants()->klass_at(bnew.index(), CHECK);
1037 }
1038 break;
1039 case Bytecodes::_multianewarray:
1040 { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
1041 k = caller_method->constants()->klass_at(mna.index(), CHECK);
1042 }
1043 break;
1044 case Bytecodes::_instanceof:
1045 { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
1046 k = caller_method->constants()->klass_at(io.index(), CHECK);
1047 }
1048 break;
1049 case Bytecodes::_checkcast:
1050 { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
1051 k = caller_method->constants()->klass_at(cc.index(), CHECK);
1052 }
1053 break;
1054 case Bytecodes::_anewarray:
1055 { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
1056 Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
1057 k = ek->array_klass(CHECK);
1058 }
1059 break;
1060 case Bytecodes::_ldc:
1061 case Bytecodes::_ldc_w:
1062 case Bytecodes::_ldc2_w:
1063 {
1064 Bytecode_loadconstant cc(caller_method, bci);
1065 oop m = cc.resolve_constant(CHECK);
1066 mirror = Handle(current, m);
1067 }
1068 break;
1069 default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
1070 }
1071 load_klass = k;
1072 } else if (stub_id == C1StubId::load_appendix_patching_id) {
1073 Bytecode_invoke bytecode(caller_method, bci);
1074 Bytecodes::Code bc = bytecode.invoke_code();
1075
1076 CallInfo info;
1077 constantPoolHandle pool(current, caller_method->constants());
1078 int index = bytecode.index();
1079 LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
1080 switch (bc) {
1081 case Bytecodes::_invokehandle: {
1082 ResolvedMethodEntry* entry = pool->cache()->set_method_handle(index, info);
1083 appendix = Handle(current, pool->cache()->appendix_if_resolved(entry));
1084 break;
1085 }
1086 case Bytecodes::_invokedynamic: {
1087 appendix = Handle(current, pool->cache()->set_dynamic_call(info, index));
1088 break;
1089 }
1090 default: fatal("unexpected bytecode for load_appendix_patching_id");
1091 }
1092 } else {
1093 ShouldNotReachHere();
1094 }
1095
1096 if (deoptimize_for_volatile || deoptimize_for_atomic) {
1097 // At compile time we assumed the field wasn't volatile/atomic but after
1098 // loading it turns out it was volatile/atomic so we have to throw the
1099 // compiled code out and let it be regenerated.
1100 if (TracePatching) {
1101 if (deoptimize_for_volatile) {
1102 tty->print_cr("Deoptimizing for patching volatile field reference");
1103 }
1104 if (deoptimize_for_atomic) {
1105 tty->print_cr("Deoptimizing for patching atomic field reference");
1106 }
1107 }
1108
1109 // It's possible the nmethod was invalidated in the last
1110 // safepoint, but if it's still alive then make it not_entrant.
1111 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1112 if (nm != nullptr) {
1113 nm->make_not_entrant("C1 code patch");
1114 }
1115
1116 Deoptimization::deoptimize_frame(current, caller_frame.id());
1117
1118 // Return to the now deoptimized frame.
1119 }
1120
1121 // Now copy code back
1122
1123 {
1124 MutexLocker ml_code (current, CodeCache_lock, Mutex::_no_safepoint_check_flag);
1125 //
1126 // Deoptimization may have happened while we waited for the lock.
1127 // In that case we don't bother to do any patching we just return
1128 // and let the deopt happen
1129 if (!caller_is_deopted(current)) {
1130 NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
1131 address instr_pc = jump->jump_destination();
1132 NativeInstruction* ni = nativeInstruction_at(instr_pc);
1133 if (ni->is_jump() ) {
1134 // the jump has not been patched yet
1135 // The jump destination is slow case and therefore not part of the stubs
1136 // (stubs are only for StaticCalls)
1137
1138 // format of buffer
1139 // ....
1140 // instr byte 0 <-- copy_buff
1141 // instr byte 1
1142 // ..
1143 // instr byte n-1
1144 // n
1145 // .... <-- call destination
1146
1147 address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
1148 unsigned char* byte_count = (unsigned char*) (stub_location - 1);
1149 unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
1150 unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
1151 address copy_buff = stub_location - *byte_skip - *byte_count;
1152 address being_initialized_entry = stub_location - *being_initialized_entry_offset;
1153 if (TracePatching) {
1154 ttyLocker ttyl;
1155 tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT " (%s)", Bytecodes::name(code), bci,
1156 p2i(instr_pc), (stub_id == C1StubId::access_field_patching_id) ? "field" : "klass");
1157 nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
1158 assert(caller_code != nullptr, "nmethod not found");
1159
1160 // NOTE we use pc() not original_pc() because we already know they are
1161 // identical otherwise we'd have never entered this block of code
1162
1163 const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
1164 assert(map != nullptr, "null check");
1165 map->print();
1166 tty->cr();
1167
1168 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1169 }
1170 // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
1171 bool do_patch = true;
1172 if (stub_id == C1StubId::access_field_patching_id) {
1173 // The offset may not be correct if the class was not loaded at code generation time.
1174 // Set it now.
1175 NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
1176 assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1177 assert(patch_field_offset >= 0, "illegal offset");
1178 n_move->add_offset_in_bytes(patch_field_offset);
1179 } else if (load_klass_or_mirror_patch_id) {
1180 // If a getstatic or putstatic is referencing a klass which
1181 // isn't fully initialized, the patch body isn't copied into
1182 // place until initialization is complete. In this case the
1183 // patch site is setup so that any threads besides the
1184 // initializing thread are forced to come into the VM and
1185 // block.
1186 do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1187 InstanceKlass::cast(init_klass)->is_initialized();
1188 NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1189 if (jump->jump_destination() == being_initialized_entry) {
1190 assert(do_patch == true, "initialization must be complete at this point");
1191 } else {
1192 // patch the instruction <move reg, klass>
1193 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1194
1195 assert(n_copy->data() == 0 ||
1196 n_copy->data() == (intptr_t)Universe::non_oop_word(),
1197 "illegal init value");
1198 if (stub_id == C1StubId::load_klass_patching_id) {
1199 assert(load_klass != nullptr, "klass not set");
1200 n_copy->set_data((intx) (load_klass));
1201 } else {
1202 // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1203 n_copy->set_data(cast_from_oop<intx>(mirror()));
1204 }
1205
1206 if (TracePatching) {
1207 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1208 }
1209 }
1210 } else if (stub_id == C1StubId::load_appendix_patching_id) {
1211 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1212 assert(n_copy->data() == 0 ||
1213 n_copy->data() == (intptr_t)Universe::non_oop_word(),
1214 "illegal init value");
1215 n_copy->set_data(cast_from_oop<intx>(appendix()));
1216
1217 if (TracePatching) {
1218 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1219 }
1220 } else {
1221 ShouldNotReachHere();
1222 }
1223
1224 if (do_patch) {
1225 // replace instructions
1226 // first replace the tail, then the call
1227 #ifdef ARM
1228 if((load_klass_or_mirror_patch_id ||
1229 stub_id == C1StubId::load_appendix_patching_id) &&
1230 nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1231 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1232 address addr = nullptr;
1233 assert(nm != nullptr, "invalid nmethod_pc");
1234 RelocIterator mds(nm, copy_buff, copy_buff + 1);
1235 while (mds.next()) {
1236 if (mds.type() == relocInfo::oop_type) {
1237 assert(stub_id == C1StubId::load_mirror_patching_id ||
1238 stub_id == C1StubId::load_appendix_patching_id, "wrong stub id");
1239 oop_Relocation* r = mds.oop_reloc();
1240 addr = (address)r->oop_addr();
1241 break;
1242 } else if (mds.type() == relocInfo::metadata_type) {
1243 assert(stub_id == C1StubId::load_klass_patching_id, "wrong stub id");
1244 metadata_Relocation* r = mds.metadata_reloc();
1245 addr = (address)r->metadata_addr();
1246 break;
1247 }
1248 }
1249 assert(addr != nullptr, "metadata relocation must exist");
1250 copy_buff -= *byte_count;
1251 NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1252 n_copy2->set_pc_relative_offset(addr, instr_pc);
1253 }
1254 #endif
1255
1256 for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
1257 address ptr = copy_buff + i;
1258 int a_byte = (*ptr) & 0xFF;
1259 address dst = instr_pc + i;
1260 *(unsigned char*)dst = (unsigned char) a_byte;
1261 }
1262 ICache::invalidate_range(instr_pc, *byte_count);
1263 NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1264
1265 if (load_klass_or_mirror_patch_id ||
1266 stub_id == C1StubId::load_appendix_patching_id) {
1267 relocInfo::relocType rtype =
1268 (stub_id == C1StubId::load_klass_patching_id) ?
1269 relocInfo::metadata_type :
1270 relocInfo::oop_type;
1271 // update relocInfo to metadata
1272 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1273 assert(nm != nullptr, "invalid nmethod_pc");
1274
1275 // The old patch site is now a move instruction so update
1276 // the reloc info so that it will get updated during
1277 // future GCs.
1278 RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1279 relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1280 relocInfo::none, rtype);
1281 }
1282
1283 } else {
1284 ICache::invalidate_range(copy_buff, *byte_count);
1285 NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1286 }
1287 }
1288 }
1289 // If we are patching in a non-perm oop, make sure the nmethod
1290 // is on the right list.
1291 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1292 guarantee(nm != nullptr, "only nmethods can contain non-perm oops");
1293
1294 // Since we've patched some oops in the nmethod,
1295 // (re)register it with the heap.
1296 Universe::heap()->register_nmethod(nm);
1297 }
1298 JRT_END
1299
1300 #else // DEOPTIMIZE_WHEN_PATCHING
1301
1302 static bool is_patching_needed(JavaThread* current, C1StubId stub_id) {
1303 if (stub_id == C1StubId::load_klass_patching_id ||
1304 stub_id == C1StubId::load_mirror_patching_id) {
1305 // last java frame on stack
1306 vframeStream vfst(current, true);
1307 assert(!vfst.at_end(), "Java frame must exist");
1308
1309 methodHandle caller_method(current, vfst.method());
1310 int bci = vfst.bci();
1311 Bytecodes::Code code = caller_method()->java_code_at(bci);
1312
1313 switch (code) {
1314 case Bytecodes::_new:
1315 case Bytecodes::_anewarray:
1316 case Bytecodes::_multianewarray:
1317 case Bytecodes::_instanceof:
1318 case Bytecodes::_checkcast: {
1319 Bytecode bc(caller_method(), caller_method->bcp_from(bci));
1320 constantTag tag = caller_method->constants()->tag_at(bc.get_index_u2(code));
1321 if (tag.is_unresolved_klass_in_error()) {
1322 return false; // throws resolution error
1323 }
1324 break;
1325 }
1326
1327 default: break;
1328 }
1329 }
1330 return true;
1331 }
1332
1333 void Runtime1::patch_code(JavaThread* current, C1StubId stub_id) {
1334 #ifndef PRODUCT
1335 if (PrintC1Statistics) {
1336 _patch_code_slowcase_cnt++;
1337 }
1338 #endif
1339
1340 // Enable WXWrite: the function is called by c1 stub as a runtime function
1341 // (see another implementation above).
1342 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
1343
1344 if (TracePatching) {
1345 tty->print_cr("Deoptimizing because patch is needed");
1346 }
1347
1348 RegisterMap reg_map(current,
1349 RegisterMap::UpdateMap::skip,
1350 RegisterMap::ProcessFrames::include,
1351 RegisterMap::WalkContinuation::skip);
1352
1353 frame runtime_frame = current->last_frame();
1354 frame caller_frame = runtime_frame.sender(®_map);
1355 assert(caller_frame.is_compiled_frame(), "Wrong frame type");
1356
1357 if (is_patching_needed(current, stub_id)) {
1358 // Make sure the nmethod is invalidated, i.e. made not entrant.
1359 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1360 if (nm != nullptr) {
1361 nm->make_not_entrant("C1 deoptimize for patching");
1362 }
1363 }
1364
1365 Deoptimization::deoptimize_frame(current, caller_frame.id());
1366 // Return to the now deoptimized frame.
1367 postcond(caller_is_deopted(current));
1368 }
1369
1370 #endif // DEOPTIMIZE_WHEN_PATCHING
1371
1372 // Entry point for compiled code. We want to patch a nmethod.
1373 // We don't do a normal VM transition here because we want to
1374 // know after the patching is complete and any safepoint(s) are taken
1375 // if the calling nmethod was deoptimized. We do this by calling a
1376 // helper method which does the normal VM transition and when it
1377 // completes we can check for deoptimization. This simplifies the
1378 // assembly code in the cpu directories.
1379 //
1380 int Runtime1::move_klass_patching(JavaThread* current) {
1381 //
1382 // NOTE: we are still in Java
1383 //
1384 DEBUG_ONLY(NoHandleMark nhm;)
1385 {
1386 // Enter VM mode
1387 ResetNoHandleMark rnhm;
1388 patch_code(current, C1StubId::load_klass_patching_id);
1389 }
1390 // Back in JAVA, use no oops DON'T safepoint
1391
1392 // Return true if calling code is deoptimized
1393
1394 return caller_is_deopted(current);
1395 }
1396
1397 int Runtime1::move_mirror_patching(JavaThread* current) {
1398 //
1399 // NOTE: we are still in Java
1400 //
1401 DEBUG_ONLY(NoHandleMark nhm;)
1402 {
1403 // Enter VM mode
1404 ResetNoHandleMark rnhm;
1405 patch_code(current, C1StubId::load_mirror_patching_id);
1406 }
1407 // Back in JAVA, use no oops DON'T safepoint
1408
1409 // Return true if calling code is deoptimized
1410
1411 return caller_is_deopted(current);
1412 }
1413
1414 int Runtime1::move_appendix_patching(JavaThread* current) {
1415 //
1416 // NOTE: we are still in Java
1417 //
1418 DEBUG_ONLY(NoHandleMark nhm;)
1419 {
1420 // Enter VM mode
1421 ResetNoHandleMark rnhm;
1422 patch_code(current, C1StubId::load_appendix_patching_id);
1423 }
1424 // Back in JAVA, use no oops DON'T safepoint
1425
1426 // Return true if calling code is deoptimized
1427
1428 return caller_is_deopted(current);
1429 }
1430
1431 // Entry point for compiled code. We want to patch a nmethod.
1432 // We don't do a normal VM transition here because we want to
1433 // know after the patching is complete and any safepoint(s) are taken
1434 // if the calling nmethod was deoptimized. We do this by calling a
1435 // helper method which does the normal VM transition and when it
1436 // completes we can check for deoptimization. This simplifies the
1437 // assembly code in the cpu directories.
1438 //
1439 int Runtime1::access_field_patching(JavaThread* current) {
1440 //
1441 // NOTE: we are still in Java
1442 //
1443 // Handles created in this function will be deleted by the
1444 // HandleMarkCleaner in the transition to the VM.
1445 NoHandleMark nhm;
1446 {
1447 // Enter VM mode
1448 ResetNoHandleMark rnhm;
1449 patch_code(current, C1StubId::access_field_patching_id);
1450 }
1451 // Back in JAVA, use no oops DON'T safepoint
1452
1453 // Return true if calling code is deoptimized
1454
1455 return caller_is_deopted(current);
1456 }
1457
1458
1459 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1460 // for now we just print out the block id
1461 tty->print("%d ", block_id);
1462 JRT_END
1463
1464
1465 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1466 // had to return int instead of bool, otherwise there may be a mismatch
1467 // between the C calling convention and the Java one.
1468 // e.g., on x86, GCC may clear only %al when returning a bool false, but
1469 // JVM takes the whole %eax as the return value, which may misinterpret
1470 // the return value as a boolean true.
1471
1472 assert(mirror != nullptr, "should null-check on mirror before calling");
1473 Klass* k = java_lang_Class::as_Klass(mirror);
1474 return (k != nullptr && obj != nullptr && obj->is_a(k)) ? 1 : 0;
1475 JRT_END
1476
1477 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* current))
1478 ResourceMark rm;
1479
1480 RegisterMap reg_map(current,
1481 RegisterMap::UpdateMap::skip,
1482 RegisterMap::ProcessFrames::include,
1483 RegisterMap::WalkContinuation::skip);
1484 frame runtime_frame = current->last_frame();
1485 frame caller_frame = runtime_frame.sender(®_map);
1486
1487 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1488 assert (nm != nullptr, "no more nmethod?");
1489 nm->make_not_entrant("C1 predicate failed trap");
1490
1491 methodHandle m(current, nm->method());
1492 MethodData* mdo = m->method_data();
1493
1494 if (mdo == nullptr && !HAS_PENDING_EXCEPTION) {
1495 // Build an MDO. Ignore errors like OutOfMemory;
1496 // that simply means we won't have an MDO to update.
1497 Method::build_profiling_method_data(m, THREAD);
1498 if (HAS_PENDING_EXCEPTION) {
1499 // Only metaspace OOM is expected. No Java code executed.
1500 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1501 CLEAR_PENDING_EXCEPTION;
1502 }
1503 mdo = m->method_data();
1504 }
1505
1506 if (mdo != nullptr) {
1507 mdo->inc_trap_count(Deoptimization::Reason_none);
1508 }
1509
1510 if (TracePredicateFailedTraps) {
1511 stringStream ss1, ss2;
1512 vframeStream vfst(current);
1513 Method* inlinee = vfst.method();
1514 inlinee->print_short_name(&ss1);
1515 m->print_short_name(&ss2);
1516 tty->print_cr("Predicate failed trap in method %s at bci %d inlined in %s at pc " INTPTR_FORMAT, ss1.freeze(), vfst.bci(), ss2.freeze(), p2i(caller_frame.pc()));
1517 }
1518
1519
1520 Deoptimization::deoptimize_frame(current, caller_frame.id());
1521
1522 JRT_END
1523
1524 // Check exception if AbortVMOnException flag set
1525 JRT_LEAF(void, Runtime1::check_abort_on_vm_exception(oopDesc* ex))
1526 ResourceMark rm;
1527 const char* message = nullptr;
1528 if (ex->is_a(vmClasses::Throwable_klass())) {
1529 oop msg = java_lang_Throwable::message(ex);
1530 if (msg != nullptr) {
1531 message = java_lang_String::as_utf8_string(msg);
1532 }
1533 }
1534 Exceptions::debug_check_abort(ex->klass()->external_name(), message);
1535 JRT_END
1536
1537 #ifndef PRODUCT
1538 void Runtime1::print_statistics() {
1539 tty->print_cr("C1 Runtime statistics:");
1540 tty->print_cr(" _resolve_invoke_virtual_cnt: %u", SharedRuntime::_resolve_virtual_ctr);
1541 tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %u", SharedRuntime::_resolve_opt_virtual_ctr);
1542 tty->print_cr(" _resolve_invoke_static_cnt: %u", SharedRuntime::_resolve_static_ctr);
1543 tty->print_cr(" _handle_wrong_method_cnt: %u", SharedRuntime::_wrong_method_ctr);
1544 tty->print_cr(" _ic_miss_cnt: %u", SharedRuntime::_ic_miss_ctr);
1545 tty->print_cr(" _generic_arraycopystub_cnt: %u", _generic_arraycopystub_cnt);
1546 tty->print_cr(" _byte_arraycopy_cnt: %u", _byte_arraycopy_stub_cnt);
1547 tty->print_cr(" _short_arraycopy_cnt: %u", _short_arraycopy_stub_cnt);
1548 tty->print_cr(" _int_arraycopy_cnt: %u", _int_arraycopy_stub_cnt);
1549 tty->print_cr(" _long_arraycopy_cnt: %u", _long_arraycopy_stub_cnt);
1550 tty->print_cr(" _oop_arraycopy_cnt: %u", _oop_arraycopy_stub_cnt);
1551 tty->print_cr(" _arraycopy_slowcase_cnt: %u", _arraycopy_slowcase_cnt);
1552 tty->print_cr(" _arraycopy_checkcast_cnt: %u", _arraycopy_checkcast_cnt);
1553 tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%u", _arraycopy_checkcast_attempt_cnt);
1554
1555 tty->print_cr(" _new_type_array_slowcase_cnt: %u", _new_type_array_slowcase_cnt);
1556 tty->print_cr(" _new_object_array_slowcase_cnt: %u", _new_object_array_slowcase_cnt);
1557 tty->print_cr(" _new_instance_slowcase_cnt: %u", _new_instance_slowcase_cnt);
1558 tty->print_cr(" _new_multi_array_slowcase_cnt: %u", _new_multi_array_slowcase_cnt);
1559 tty->print_cr(" _monitorenter_slowcase_cnt: %u", _monitorenter_slowcase_cnt);
1560 tty->print_cr(" _monitorexit_slowcase_cnt: %u", _monitorexit_slowcase_cnt);
1561 tty->print_cr(" _patch_code_slowcase_cnt: %u", _patch_code_slowcase_cnt);
1562
1563 tty->print_cr(" _throw_range_check_exception_count: %u:", _throw_range_check_exception_count);
1564 tty->print_cr(" _throw_index_exception_count: %u:", _throw_index_exception_count);
1565 tty->print_cr(" _throw_div0_exception_count: %u:", _throw_div0_exception_count);
1566 tty->print_cr(" _throw_null_pointer_exception_count: %u:", _throw_null_pointer_exception_count);
1567 tty->print_cr(" _throw_class_cast_exception_count: %u:", _throw_class_cast_exception_count);
1568 tty->print_cr(" _throw_incompatible_class_change_error_count: %u:", _throw_incompatible_class_change_error_count);
1569 tty->print_cr(" _throw_count: %u:", _throw_count);
1570
1571 SharedRuntime::print_ic_miss_histogram();
1572 tty->cr();
1573 }
1574 #endif // PRODUCT