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/stubInfo.hpp"
66 #include "runtime/stubRoutines.hpp"
67 #include "runtime/vframe.inline.hpp"
68 #include "runtime/vframeArray.hpp"
69 #include "runtime/vm_version.hpp"
70 #include "utilities/copy.hpp"
71 #include "utilities/events.hpp"
72
73
74 // Implementation of StubAssembler
75
76 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
77 _name = name;
78 _must_gc_arguments = false;
79 _frame_size = no_frame_size;
80 _num_rt_args = 0;
81 _stub_id = stub_id;
82 }
83
84
85 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
86 _name = name;
87 _must_gc_arguments = must_gc_arguments;
88 }
89
90
91 void StubAssembler::set_frame_size(int size) {
92 if (_frame_size == no_frame_size) {
93 _frame_size = size;
94 }
95 assert(_frame_size == size, "can't change the frame size");
96 }
97
98
99 void StubAssembler::set_num_rt_args(int args) {
100 if (_num_rt_args == 0) {
101 _num_rt_args = args;
102 }
103 assert(_num_rt_args == args, "can't change the number of args");
104 }
105
106 // Implementation of Runtime1
107 CodeBlob* Runtime1::_blobs[StubInfo::C1_STUB_COUNT];
108
109 #ifndef PRODUCT
110 // statistics
111 uint Runtime1::_generic_arraycopystub_cnt = 0;
112 uint Runtime1::_arraycopy_slowcase_cnt = 0;
113 uint Runtime1::_arraycopy_checkcast_cnt = 0;
114 uint Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
115 uint Runtime1::_new_type_array_slowcase_cnt = 0;
116 uint Runtime1::_new_object_array_slowcase_cnt = 0;
117 uint Runtime1::_new_instance_slowcase_cnt = 0;
118 uint Runtime1::_new_multi_array_slowcase_cnt = 0;
119 uint Runtime1::_monitorenter_slowcase_cnt = 0;
120 uint Runtime1::_monitorexit_slowcase_cnt = 0;
121 uint Runtime1::_patch_code_slowcase_cnt = 0;
122 uint Runtime1::_throw_range_check_exception_count = 0;
123 uint Runtime1::_throw_index_exception_count = 0;
124 uint Runtime1::_throw_div0_exception_count = 0;
125 uint Runtime1::_throw_null_pointer_exception_count = 0;
126 uint Runtime1::_throw_class_cast_exception_count = 0;
127 uint Runtime1::_throw_incompatible_class_change_error_count = 0;
128 uint Runtime1::_throw_count = 0;
129
130 static uint _byte_arraycopy_stub_cnt = 0;
131 static uint _short_arraycopy_stub_cnt = 0;
132 static uint _int_arraycopy_stub_cnt = 0;
133 static uint _long_arraycopy_stub_cnt = 0;
134 static uint _oop_arraycopy_stub_cnt = 0;
135
136 address Runtime1::arraycopy_count_address(BasicType type) {
137 switch (type) {
138 case T_BOOLEAN:
139 case T_BYTE: return (address)&_byte_arraycopy_stub_cnt;
140 case T_CHAR:
141 case T_SHORT: return (address)&_short_arraycopy_stub_cnt;
142 case T_FLOAT:
143 case T_INT: return (address)&_int_arraycopy_stub_cnt;
144 case T_DOUBLE:
145 case T_LONG: return (address)&_long_arraycopy_stub_cnt;
146 case T_ARRAY:
147 case T_OBJECT: return (address)&_oop_arraycopy_stub_cnt;
148 default:
149 ShouldNotReachHere();
150 return nullptr;
151 }
152 }
153
154
155 #endif
156
157 // Simple helper to see if the caller of a runtime stub which
158 // entered the VM has been deoptimized
159
160 static bool caller_is_deopted(JavaThread* current) {
161 RegisterMap reg_map(current,
162 RegisterMap::UpdateMap::skip,
163 RegisterMap::ProcessFrames::include,
164 RegisterMap::WalkContinuation::skip);
165 frame runtime_frame = current->last_frame();
166 frame caller_frame = runtime_frame.sender(®_map);
167 assert(caller_frame.is_compiled_frame(), "must be compiled");
168 return caller_frame.is_deoptimized_frame();
169 }
170
171 // Stress deoptimization
172 static void deopt_caller(JavaThread* current) {
173 if (!caller_is_deopted(current)) {
174 RegisterMap reg_map(current,
175 RegisterMap::UpdateMap::skip,
176 RegisterMap::ProcessFrames::include,
177 RegisterMap::WalkContinuation::skip);
178 frame runtime_frame = current->last_frame();
179 frame caller_frame = runtime_frame.sender(®_map);
180 Deoptimization::deoptimize_frame(current, caller_frame.id());
181 assert(caller_is_deopted(current), "Must be deoptimized");
182 }
183 }
184
185 class C1StubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
186 private:
187 StubId _id;
188 public:
189 C1StubAssemblerCodeGenClosure(StubId id) : _id(id) {
190 assert(StubInfo::is_c1(_id), "not a c1 stub id %s", StubInfo::name(_id));
191 }
192 virtual OopMapSet* generate_code(StubAssembler* sasm) {
193 return Runtime1::generate_code_for(_id, sasm);
194 }
195 };
196
197 CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, StubId id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
198 if (id != StubId::NO_STUBID) {
199 CodeBlob* blob = AOTCodeCache::load_code_blob(AOTCodeEntry::C1Blob, StubInfo::blob(id));
200 if (blob != nullptr) {
201 return blob;
202 }
203 }
204
205 ResourceMark rm;
206 // create code buffer for code storage
207 CodeBuffer code(buffer_blob);
208
209 OopMapSet* oop_maps;
210 int frame_size;
211 bool must_gc_arguments;
212
213 Compilation::setup_code_buffer(&code, 0);
214
215 // create assembler for code generation
216 StubAssembler* sasm = new StubAssembler(&code, name, (int)id);
217 // generate code for runtime stub
218 oop_maps = cl->generate_code(sasm);
219 assert(oop_maps == nullptr || sasm->frame_size() != no_frame_size,
220 "if stub has an oop map it must have a valid frame size");
221 assert(!expect_oop_map || oop_maps != nullptr, "must have an oopmap");
222
223 // align so printing shows nop's instead of random code at the end (SimpleStubs are aligned)
224 sasm->align(BytesPerWord);
225 // make sure all code is in code buffer
226 sasm->flush();
227
228 frame_size = sasm->frame_size();
229 must_gc_arguments = sasm->must_gc_arguments();
230 // create blob - distinguish a few special cases
231 CodeBlob* blob = RuntimeStub::new_runtime_stub(name,
232 &code,
233 CodeOffsets::frame_never_safe,
234 frame_size,
235 oop_maps,
236 must_gc_arguments,
237 false /* alloc_fail_is_fatal */ );
238 if (blob != nullptr && (int)id >= 0) {
239 AOTCodeCache::store_code_blob(*blob, AOTCodeEntry::C1Blob, StubInfo::blob(id));
240 }
241 return blob;
242 }
243
244 bool Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubId id) {
245 assert(StubInfo::is_c1(id), "not a c1 stub %s", StubInfo::name(id));
246 bool expect_oop_map = true;
247 #ifdef ASSERT
248 // Make sure that stubs that need oopmaps have them
249 switch (id) {
250 // These stubs don't need to have an oopmap
251 case StubId::c1_dtrace_object_alloc_id:
252 case StubId::c1_slow_subtype_check_id:
253 case StubId::c1_fpu2long_stub_id:
254 case StubId::c1_unwind_exception_id:
255 case StubId::c1_counter_overflow_id:
256 case StubId::c1_is_instance_of_id:
257 expect_oop_map = false;
258 break;
259 default:
260 break;
261 }
262 #endif
263 C1StubAssemblerCodeGenClosure cl(id);
264 CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
265 // install blob
266 int idx = StubInfo::c1_offset(id); // will assert on non-c1 id
267 _blobs[idx] = blob;
268 return blob != nullptr;
269 }
270
271 bool Runtime1::initialize(BufferBlob* blob) {
272 // platform-dependent initialization
273 initialize_pd();
274 // iterate blobs in C1 group and generate a single stub per blob
275 StubId id = StubInfo::stub_base(StubGroup::C1);
276 StubId limit = StubInfo::next(StubInfo::stub_max(StubGroup::C1));
277 for (; id != limit; id = StubInfo::next(id)) {
278 if (!generate_blob_for(blob, id)) {
279 return false;
280 }
281 if (id == StubId::c1_forward_exception_id) {
282 // publish early c1 stubs at this point so later stubs can refer to them
283 AOTCodeCache::init_early_c1_table();
284 }
285 }
286 // printing
287 #ifndef PRODUCT
288 if (PrintSimpleStubs) {
289 ResourceMark rm;
290 id = StubInfo::stub_base(StubGroup::C1);
291 for (; id != limit; id = StubInfo::next(id)) {
292 CodeBlob* blob = blob_for(id);
293 blob->print();
294 if (blob->oop_maps() != nullptr) {
295 blob->oop_maps()->print();
296 }
297 }
298 }
299 #endif
300 BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
301 return bs->generate_c1_runtime_stubs(blob);
302 }
303
304 CodeBlob* Runtime1::blob_for(StubId id) {
305 int idx = StubInfo::c1_offset(id); // will assert on non-c1 id
306 return _blobs[idx];
307 }
308
309
310 const char* Runtime1::name_for(StubId id) {
311 return StubInfo::name(id);
312 }
313
314 const char* Runtime1::name_for_address(address entry) {
315 // iterate stubs starting from C1 group base
316 StubId id = StubInfo::stub_base(StubGroup::C1);
317 StubId limit = StubInfo::next(StubInfo::stub_max(StubGroup::C1));
318 for (; id != limit; id = StubInfo::next(id)) {
319 if (entry == entry_for(id)) return StubInfo::name(id);
320 }
321
322 #define FUNCTION_CASE(a, f) \
323 if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f)) return #f
324
325 FUNCTION_CASE(entry, os::javaTimeMillis);
326 FUNCTION_CASE(entry, os::javaTimeNanos);
327 FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
328 FUNCTION_CASE(entry, SharedRuntime::d2f);
329 FUNCTION_CASE(entry, SharedRuntime::d2i);
330 FUNCTION_CASE(entry, SharedRuntime::d2l);
331 FUNCTION_CASE(entry, SharedRuntime::dcos);
332 FUNCTION_CASE(entry, SharedRuntime::dexp);
333 FUNCTION_CASE(entry, SharedRuntime::dlog);
334 FUNCTION_CASE(entry, SharedRuntime::dlog10);
335 FUNCTION_CASE(entry, SharedRuntime::dpow);
336 FUNCTION_CASE(entry, SharedRuntime::drem);
337 FUNCTION_CASE(entry, SharedRuntime::dsin);
338 FUNCTION_CASE(entry, SharedRuntime::dtan);
339 FUNCTION_CASE(entry, SharedRuntime::f2i);
340 FUNCTION_CASE(entry, SharedRuntime::f2l);
341 FUNCTION_CASE(entry, SharedRuntime::frem);
342 FUNCTION_CASE(entry, SharedRuntime::l2d);
343 FUNCTION_CASE(entry, SharedRuntime::l2f);
344 FUNCTION_CASE(entry, SharedRuntime::ldiv);
345 FUNCTION_CASE(entry, SharedRuntime::lmul);
346 FUNCTION_CASE(entry, SharedRuntime::lrem);
347 FUNCTION_CASE(entry, SharedRuntime::lrem);
348 FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
349 FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
350 FUNCTION_CASE(entry, is_instance_of);
351 FUNCTION_CASE(entry, trace_block_entry);
352 #ifdef JFR_HAVE_INTRINSICS
353 FUNCTION_CASE(entry, JfrTime::time_function());
354 #endif
355 FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
356 FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
357 FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
358 FUNCTION_CASE(entry, StubRoutines::dexp());
359 FUNCTION_CASE(entry, StubRoutines::dlog());
360 FUNCTION_CASE(entry, StubRoutines::dlog10());
361 FUNCTION_CASE(entry, StubRoutines::dpow());
362 FUNCTION_CASE(entry, StubRoutines::dsin());
363 FUNCTION_CASE(entry, StubRoutines::dcos());
364 FUNCTION_CASE(entry, StubRoutines::dtan());
365 FUNCTION_CASE(entry, StubRoutines::dsinh());
366 FUNCTION_CASE(entry, StubRoutines::dtanh());
367 FUNCTION_CASE(entry, StubRoutines::dcbrt());
368
369 #undef FUNCTION_CASE
370
371 // Soft float adds more runtime names.
372 return pd_name_for_address(entry);
373 }
374
375
376 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* current, Klass* klass))
377 #ifndef PRODUCT
378 if (PrintC1Statistics) {
379 _new_instance_slowcase_cnt++;
380 }
381 #endif
382 assert(klass->is_klass(), "not a class");
383 Handle holder(current, klass->klass_holder()); // keep the klass alive
384 InstanceKlass* h = InstanceKlass::cast(klass);
385 h->check_valid_for_instantiation(true, CHECK);
386 // make sure klass is initialized
387 h->initialize(CHECK);
388 // allocate instance and return via TLS
389 oop obj = h->allocate_instance(CHECK);
390 current->set_vm_result_oop(obj);
391 JRT_END
392
393
394 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* current, Klass* klass, jint length))
395 #ifndef PRODUCT
396 if (PrintC1Statistics) {
397 _new_type_array_slowcase_cnt++;
398 }
399 #endif
400 // Note: no handle for klass needed since they are not used
401 // anymore after new_typeArray() and no GC can happen before.
402 // (This may have to change if this code changes!)
403 assert(klass->is_klass(), "not a class");
404 BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
405 oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
406 current->set_vm_result_oop(obj);
407 // This is pretty rare but this runtime patch is stressful to deoptimization
408 // if we deoptimize here so force a deopt to stress the path.
409 if (DeoptimizeALot) {
410 deopt_caller(current);
411 }
412
413 JRT_END
414
415
416 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* current, Klass* array_klass, jint length))
417 #ifndef PRODUCT
418 if (PrintC1Statistics) {
419 _new_object_array_slowcase_cnt++;
420 }
421 #endif
422 // Note: no handle for klass needed since they are not used
423 // anymore after new_objArray() and no GC can happen before.
424 // (This may have to change if this code changes!)
425 assert(array_klass->is_klass(), "not a class");
426 Handle holder(current, array_klass->klass_holder()); // keep the klass alive
427 Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
428 objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
429 current->set_vm_result_oop(obj);
430 // This is pretty rare but this runtime patch is stressful to deoptimization
431 // if we deoptimize here so force a deopt to stress the path.
432 if (DeoptimizeALot) {
433 deopt_caller(current);
434 }
435 JRT_END
436
437
438 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* current, Klass* klass, int rank, jint* dims))
439 #ifndef PRODUCT
440 if (PrintC1Statistics) {
441 _new_multi_array_slowcase_cnt++;
442 }
443 #endif
444 assert(klass->is_klass(), "not a class");
445 assert(rank >= 1, "rank must be nonzero");
446 Handle holder(current, klass->klass_holder()); // keep the klass alive
447 oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
448 current->set_vm_result_oop(obj);
449 JRT_END
450
451
452 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* current, StubId id))
453 tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", (int)id);
454 JRT_END
455
456
457 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* current, oopDesc* obj))
458 ResourceMark rm(current);
459 const char* klass_name = obj->klass()->external_name();
460 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayStoreException(), klass_name);
461 JRT_END
462
463
464 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
465 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
466 // method) method is passed as an argument. In order to do that it is embedded in the code as
467 // a constant.
468 static nmethod* counter_overflow_helper(JavaThread* current, int branch_bci, Method* m) {
469 nmethod* osr_nm = nullptr;
470 methodHandle method(current, m);
471
472 RegisterMap map(current,
473 RegisterMap::UpdateMap::skip,
474 RegisterMap::ProcessFrames::include,
475 RegisterMap::WalkContinuation::skip);
476 frame fr = current->last_frame().sender(&map);
477 nmethod* nm = (nmethod*) fr.cb();
478 assert(nm!= nullptr && nm->is_nmethod(), "Sanity check");
479 methodHandle enclosing_method(current, nm->method());
480
481 CompLevel level = (CompLevel)nm->comp_level();
482 int bci = InvocationEntryBci;
483 if (branch_bci != InvocationEntryBci) {
484 // Compute destination bci
485 address pc = method()->code_base() + branch_bci;
486 Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
487 int offset = 0;
488 switch (branch) {
489 case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
490 case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
491 case Bytecodes::_if_icmple: case Bytecodes::_ifle:
492 case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
493 case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
494 case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
495 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
496 offset = (int16_t)Bytes::get_Java_u2(pc + 1);
497 break;
498 case Bytecodes::_goto_w:
499 offset = Bytes::get_Java_u4(pc + 1);
500 break;
501 default: ;
502 }
503 bci = branch_bci + offset;
504 }
505 osr_nm = CompilationPolicy::event(enclosing_method, method, branch_bci, bci, level, nm, current);
506 return osr_nm;
507 }
508
509 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* current, int bci, Method* method))
510 nmethod* osr_nm;
511 JRT_BLOCK_NO_ASYNC
512 osr_nm = counter_overflow_helper(current, bci, method);
513 if (osr_nm != nullptr) {
514 RegisterMap map(current,
515 RegisterMap::UpdateMap::skip,
516 RegisterMap::ProcessFrames::include,
517 RegisterMap::WalkContinuation::skip);
518 frame fr = current->last_frame().sender(&map);
519 Deoptimization::deoptimize_frame(current, fr.id());
520 }
521 JRT_BLOCK_END
522 return nullptr;
523 JRT_END
524
525 extern void vm_exit(int code);
526
527 // Enter this method from compiled code handler below. This is where we transition
528 // to VM mode. This is done as a helper routine so that the method called directly
529 // from compiled code does not have to transition to VM. This allows the entry
530 // method to see if the nmethod that we have just looked up a handler for has
531 // been deoptimized while we were in the vm. This simplifies the assembly code
532 // cpu directories.
533 //
534 // We are entering here from exception stub (via the entry method below)
535 // If there is a compiled exception handler in this method, we will continue there;
536 // otherwise we will unwind the stack and continue at the caller of top frame method
537 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
538 // control the area where we can allow a safepoint. After we exit the safepoint area we can
539 // check to see if the handler we are going to return is now in a nmethod that has
540 // been deoptimized. If that is the case we return the deopt blob
541 // unpack_with_exception entry instead. This makes life for the exception blob easier
542 // because making that same check and diverting is painful from assembly language.
543 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* current, oopDesc* ex, address pc, nmethod*& nm))
544 // Reset method handle flag.
545 current->set_is_method_handle_return(false);
546
547 Handle exception(current, ex);
548
549 // This function is called when we are about to throw an exception. Therefore,
550 // we have to poll the stack watermark barrier to make sure that not yet safe
551 // stack frames are made safe before returning into them.
552 if (current->last_frame().cb() == Runtime1::blob_for(StubId::c1_handle_exception_from_callee_id)) {
553 // The StubId::c1_handle_exception_from_callee_id handler is invoked after the
554 // frame has been unwound. It instead builds its own stub frame, to call the
555 // runtime. But the throwing frame has already been unwound here.
556 StackWatermarkSet::after_unwind(current);
557 }
558
559 nm = CodeCache::find_nmethod(pc);
560 assert(nm != nullptr, "this is not an nmethod");
561 // Adjust the pc as needed/
562 if (nm->is_deopt_pc(pc)) {
563 RegisterMap map(current,
564 RegisterMap::UpdateMap::skip,
565 RegisterMap::ProcessFrames::include,
566 RegisterMap::WalkContinuation::skip);
567 frame exception_frame = current->last_frame().sender(&map);
568 // if the frame isn't deopted then pc must not correspond to the caller of last_frame
569 assert(exception_frame.is_deoptimized_frame(), "must be deopted");
570 pc = exception_frame.pc();
571 }
572 assert(exception.not_null(), "null exceptions should be handled by throw_exception");
573 // Check that exception is a subclass of Throwable
574 assert(exception->is_a(vmClasses::Throwable_klass()),
575 "Exception not subclass of Throwable");
576
577 // debugging support
578 // tracing
579 if (log_is_enabled(Info, exceptions)) {
580 ResourceMark rm; // print_value_string
581 stringStream tempst;
582 assert(nm->method() != nullptr, "Unexpected null method()");
583 tempst.print("C1 compiled method <%s>\n"
584 " at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
585 nm->method()->print_value_string(), p2i(pc), p2i(current));
586 Exceptions::log_exception(exception, tempst.freeze());
587 }
588 // for AbortVMOnException flag
589 Exceptions::debug_check_abort(exception);
590
591 // Check the stack guard pages and re-enable them if necessary and there is
592 // enough space on the stack to do so. Use fast exceptions only if the guard
593 // pages are enabled.
594 bool guard_pages_enabled = current->stack_overflow_state()->reguard_stack_if_needed();
595
596 if (JvmtiExport::can_post_on_exceptions()) {
597 // To ensure correct notification of exception catches and throws
598 // we have to deoptimize here. If we attempted to notify the
599 // catches and throws during this exception lookup it's possible
600 // we could deoptimize on the way out of the VM and end back in
601 // the interpreter at the throw site. This would result in double
602 // notifications since the interpreter would also notify about
603 // these same catches and throws as it unwound the frame.
604
605 RegisterMap reg_map(current,
606 RegisterMap::UpdateMap::include,
607 RegisterMap::ProcessFrames::include,
608 RegisterMap::WalkContinuation::skip);
609 frame stub_frame = current->last_frame();
610 frame caller_frame = stub_frame.sender(®_map);
611
612 // We don't really want to deoptimize the nmethod itself since we
613 // can actually continue in the exception handler ourselves but I
614 // don't see an easy way to have the desired effect.
615 Deoptimization::deoptimize_frame(current, caller_frame.id());
616 assert(caller_is_deopted(current), "Must be deoptimized");
617
618 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
619 }
620
621 // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
622 if (guard_pages_enabled) {
623 address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
624 if (fast_continuation != nullptr) {
625 // Set flag if return address is a method handle call site.
626 current->set_is_method_handle_return(nm->is_method_handle_return(pc));
627 return fast_continuation;
628 }
629 }
630
631 // If the stack guard pages are enabled, check whether there is a handler in
632 // the current method. Otherwise (guard pages disabled), force an unwind and
633 // skip the exception cache update (i.e., just leave continuation as null).
634 address continuation = nullptr;
635 if (guard_pages_enabled) {
636
637 // New exception handling mechanism can support inlined methods
638 // with exception handlers since the mappings are from PC to PC
639
640 // Clear out the exception oop and pc since looking up an
641 // exception handler can cause class loading, which might throw an
642 // exception and those fields are expected to be clear during
643 // normal bytecode execution.
644 current->clear_exception_oop_and_pc();
645
646 bool recursive_exception = false;
647 continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
648 // If an exception was thrown during exception dispatch, the exception oop may have changed
649 current->set_exception_oop(exception());
650 current->set_exception_pc(pc);
651
652 // the exception cache is used only by non-implicit exceptions
653 // Update the exception cache only when there didn't happen
654 // another exception during the computation of the compiled
655 // exception handler. Checking for exception oop equality is not
656 // sufficient because some exceptions are pre-allocated and reused.
657 if (continuation != nullptr && !recursive_exception) {
658 nm->add_handler_for_exception_and_pc(exception, pc, continuation);
659 }
660 }
661
662 current->set_vm_result_oop(exception());
663 // Set flag if return address is a method handle call site.
664 current->set_is_method_handle_return(nm->is_method_handle_return(pc));
665
666 if (log_is_enabled(Info, exceptions)) {
667 ResourceMark rm;
668 log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
669 " for exception thrown at PC " PTR_FORMAT,
670 p2i(current), p2i(continuation), p2i(pc));
671 }
672
673 return continuation;
674 JRT_END
675
676 // Enter this method from compiled code only if there is a Java exception handler
677 // in the method handling the exception.
678 // We are entering here from exception stub. We don't do a normal VM transition here.
679 // We do it in a helper. This is so we can check to see if the nmethod we have just
680 // searched for an exception handler has been deoptimized in the meantime.
681 address Runtime1::exception_handler_for_pc(JavaThread* current) {
682 oop exception = current->exception_oop();
683 address pc = current->exception_pc();
684 // Still in Java mode
685 DEBUG_ONLY(NoHandleMark nhm);
686 nmethod* nm = nullptr;
687 address continuation = nullptr;
688 {
689 // Enter VM mode by calling the helper
690 ResetNoHandleMark rnhm;
691 continuation = exception_handler_for_pc_helper(current, exception, pc, nm);
692 }
693 // Back in JAVA, use no oops DON'T safepoint
694
695 // Now check to see if the nmethod we were called from is now deoptimized.
696 // If so we must return to the deopt blob and deoptimize the nmethod
697 if (nm != nullptr && caller_is_deopted(current)) {
698 continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
699 }
700
701 assert(continuation != nullptr, "no handler found");
702 return continuation;
703 }
704
705
706 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* current, int index, arrayOopDesc* a))
707 #ifndef PRODUCT
708 if (PrintC1Statistics) {
709 _throw_range_check_exception_count++;
710 }
711 #endif
712 const int len = 35;
713 assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
714 char message[2 * jintAsStringSize + len];
715 os::snprintf_checked(message, sizeof(message), "Index %d out of bounds for length %d", index, a->length());
716 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
717 JRT_END
718
719
720 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* current, int index))
721 #ifndef PRODUCT
722 if (PrintC1Statistics) {
723 _throw_index_exception_count++;
724 }
725 #endif
726 char message[16];
727 os::snprintf_checked(message, sizeof(message), "%d", index);
728 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
729 JRT_END
730
731
732 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* current))
733 #ifndef PRODUCT
734 if (PrintC1Statistics) {
735 _throw_div0_exception_count++;
736 }
737 #endif
738 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
739 JRT_END
740
741
742 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* current))
743 #ifndef PRODUCT
744 if (PrintC1Statistics) {
745 _throw_null_pointer_exception_count++;
746 }
747 #endif
748 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_NullPointerException());
749 JRT_END
750
751
752 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* current, oopDesc* object))
753 #ifndef PRODUCT
754 if (PrintC1Statistics) {
755 _throw_class_cast_exception_count++;
756 }
757 #endif
758 ResourceMark rm(current);
759 char* message = SharedRuntime::generate_class_cast_message(current, object->klass());
760 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ClassCastException(), message);
761 JRT_END
762
763
764 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* current))
765 #ifndef PRODUCT
766 if (PrintC1Statistics) {
767 _throw_incompatible_class_change_error_count++;
768 }
769 #endif
770 ResourceMark rm(current);
771 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IncompatibleClassChangeError());
772 JRT_END
773
774
775 JRT_BLOCK_ENTRY(void, Runtime1::monitorenter(JavaThread* current, oopDesc* obj, BasicObjectLock* lock))
776 #ifndef PRODUCT
777 if (PrintC1Statistics) {
778 _monitorenter_slowcase_cnt++;
779 }
780 #endif
781 if (LockingMode == LM_MONITOR) {
782 lock->set_obj(obj);
783 }
784 assert(obj == lock->obj(), "must match");
785 SharedRuntime::monitor_enter_helper(obj, lock->lock(), current);
786 JRT_END
787
788
789 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* current, BasicObjectLock* lock))
790 assert(current == JavaThread::current(), "pre-condition");
791 #ifndef PRODUCT
792 if (PrintC1Statistics) {
793 _monitorexit_slowcase_cnt++;
794 }
795 #endif
796 assert(current->last_Java_sp(), "last_Java_sp must be set");
797 oop obj = lock->obj();
798 assert(oopDesc::is_oop(obj), "must be null or an object");
799 SharedRuntime::monitor_exit_helper(obj, lock->lock(), current);
800 JRT_END
801
802 // Cf. OptoRuntime::deoptimize_caller_frame
803 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* current, jint trap_request))
804 // Called from within the owner thread, so no need for safepoint
805 RegisterMap reg_map(current,
806 RegisterMap::UpdateMap::skip,
807 RegisterMap::ProcessFrames::include,
808 RegisterMap::WalkContinuation::skip);
809 frame stub_frame = current->last_frame();
810 assert(stub_frame.is_runtime_frame(), "Sanity check");
811 frame caller_frame = stub_frame.sender(®_map);
812 nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
813 assert(nm != nullptr, "Sanity check");
814 methodHandle method(current, nm->method());
815 assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
816 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
817 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
818
819 if (action == Deoptimization::Action_make_not_entrant) {
820 if (nm->make_not_entrant(nmethod::InvalidationReason::C1_DEOPTIMIZE)) {
821 if (reason == Deoptimization::Reason_tenured) {
822 MethodData* trap_mdo = Deoptimization::get_method_data(current, method, true /*create_if_missing*/);
823 if (trap_mdo != nullptr) {
824 trap_mdo->inc_tenure_traps();
825 }
826 }
827 }
828 }
829
830 // Deoptimize the caller frame.
831 Deoptimization::deoptimize_frame(current, caller_frame.id());
832 // Return to the now deoptimized frame.
833 JRT_END
834
835
836 #ifndef DEOPTIMIZE_WHEN_PATCHING
837
838 static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
839 Bytecode_field field_access(caller, bci);
840 // This can be static or non-static field access
841 Bytecodes::Code code = field_access.code();
842
843 // We must load class, initialize class and resolve the field
844 fieldDescriptor result; // initialize class if needed
845 constantPoolHandle constants(THREAD, caller->constants());
846 LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
847 return result.field_holder();
848 }
849
850
851 //
852 // This routine patches sites where a class wasn't loaded or
853 // initialized at the time the code was generated. It handles
854 // references to classes, fields and forcing of initialization. Most
855 // of the cases are straightforward and involving simply forcing
856 // resolution of a class, rewriting the instruction stream with the
857 // needed constant and replacing the call in this function with the
858 // patched code. The case for static field is more complicated since
859 // the thread which is in the process of initializing a class can
860 // access it's static fields but other threads can't so the code
861 // either has to deoptimize when this case is detected or execute a
862 // check that the current thread is the initializing thread. The
863 // current
864 //
865 // Patches basically look like this:
866 //
867 //
868 // patch_site: jmp patch stub ;; will be patched
869 // continue: ...
870 // ...
871 // ...
872 // ...
873 //
874 // They have a stub which looks like this:
875 //
876 // ;; patch body
877 // movl <const>, reg (for class constants)
878 // <or> movl [reg1 + <const>], reg (for field offsets)
879 // <or> movl reg, [reg1 + <const>] (for field offsets)
880 // <being_init offset> <bytes to copy> <bytes to skip>
881 // patch_stub: call Runtime1::patch_code (through a runtime stub)
882 // jmp patch_site
883 //
884 //
885 // A normal patch is done by rewriting the patch body, usually a move,
886 // and then copying it into place over top of the jmp instruction
887 // being careful to flush caches and doing it in an MP-safe way. The
888 // constants following the patch body are used to find various pieces
889 // of the patch relative to the call site for Runtime1::patch_code.
890 // The case for getstatic and putstatic is more complicated because
891 // getstatic and putstatic have special semantics when executing while
892 // the class is being initialized. getstatic/putstatic on a class
893 // which is being_initialized may be executed by the initializing
894 // thread but other threads have to block when they execute it. This
895 // is accomplished in compiled code by executing a test of the current
896 // thread against the initializing thread of the class. It's emitted
897 // as boilerplate in their stub which allows the patched code to be
898 // executed before it's copied back into the main body of the nmethod.
899 //
900 // being_init: get_thread(<tmp reg>
901 // cmpl [reg1 + <init_thread_offset>], <tmp reg>
902 // jne patch_stub
903 // movl [reg1 + <const>], reg (for field offsets) <or>
904 // movl reg, [reg1 + <const>] (for field offsets)
905 // jmp continue
906 // <being_init offset> <bytes to copy> <bytes to skip>
907 // patch_stub: jmp Runtime1::patch_code (through a runtime stub)
908 // jmp patch_site
909 //
910 // If the class is being initialized the patch body is rewritten and
911 // the patch site is rewritten to jump to being_init, instead of
912 // patch_stub. Whenever this code is executed it checks the current
913 // thread against the initializing thread so other threads will enter
914 // the runtime and end up blocked waiting the class to finish
915 // initializing inside the calls to resolve_field below. The
916 // initializing class will continue on it's way. Once the class is
917 // fully_initialized, the intializing_thread of the class becomes
918 // null, so the next thread to execute this code will fail the test,
919 // call into patch_code and complete the patching process by copying
920 // the patch body back into the main part of the nmethod and resume
921 // executing.
922
923 // NB:
924 //
925 // Patchable instruction sequences inherently exhibit race conditions,
926 // where thread A is patching an instruction at the same time thread B
927 // is executing it. The algorithms we use ensure that any observation
928 // that B can make on any intermediate states during A's patching will
929 // always end up with a correct outcome. This is easiest if there are
930 // few or no intermediate states. (Some inline caches have two
931 // related instructions that must be patched in tandem. For those,
932 // intermediate states seem to be unavoidable, but we will get the
933 // right answer from all possible observation orders.)
934 //
935 // When patching the entry instruction at the head of a method, or a
936 // linkable call instruction inside of a method, we try very hard to
937 // use a patch sequence which executes as a single memory transaction.
938 // This means, in practice, that when thread A patches an instruction,
939 // it should patch a 32-bit or 64-bit word that somehow overlaps the
940 // instruction or is contained in it. We believe that memory hardware
941 // will never break up such a word write, if it is naturally aligned
942 // for the word being written. We also know that some CPUs work very
943 // hard to create atomic updates even of naturally unaligned words,
944 // but we don't want to bet the farm on this always working.
945 //
946 // Therefore, if there is any chance of a race condition, we try to
947 // patch only naturally aligned words, as single, full-word writes.
948
949 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* current, StubId stub_id ))
950 #ifndef PRODUCT
951 if (PrintC1Statistics) {
952 _patch_code_slowcase_cnt++;
953 }
954 #endif
955
956 ResourceMark rm(current);
957 RegisterMap reg_map(current,
958 RegisterMap::UpdateMap::skip,
959 RegisterMap::ProcessFrames::include,
960 RegisterMap::WalkContinuation::skip);
961 frame runtime_frame = current->last_frame();
962 frame caller_frame = runtime_frame.sender(®_map);
963
964 // last java frame on stack
965 vframeStream vfst(current, true);
966 assert(!vfst.at_end(), "Java frame must exist");
967
968 methodHandle caller_method(current, vfst.method());
969 // Note that caller_method->code() may not be same as caller_code because of OSR's
970 // Note also that in the presence of inlining it is not guaranteed
971 // that caller_method() == caller_code->method()
972
973 int bci = vfst.bci();
974 Bytecodes::Code code = caller_method()->java_code_at(bci);
975
976 // this is used by assertions in the access_field_patching_id
977 BasicType patch_field_type = T_ILLEGAL;
978 bool deoptimize_for_volatile = false;
979 bool deoptimize_for_atomic = false;
980 int patch_field_offset = -1;
981 Klass* init_klass = nullptr; // klass needed by load_klass_patching code
982 Klass* load_klass = nullptr; // klass needed by load_klass_patching code
983 Handle mirror(current, nullptr); // oop needed by load_mirror_patching code
984 Handle appendix(current, nullptr); // oop needed by appendix_patching code
985 bool load_klass_or_mirror_patch_id =
986 (stub_id == StubId::c1_load_klass_patching_id || stub_id == StubId::c1_load_mirror_patching_id);
987
988 if (stub_id == StubId::c1_access_field_patching_id) {
989
990 Bytecode_field field_access(caller_method, bci);
991 fieldDescriptor result; // initialize class if needed
992 Bytecodes::Code code = field_access.code();
993 constantPoolHandle constants(current, caller_method->constants());
994 LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
995 patch_field_offset = result.offset();
996
997 // If we're patching a field which is volatile then at compile it
998 // must not have been know to be volatile, so the generated code
999 // isn't correct for a volatile reference. The nmethod has to be
1000 // deoptimized so that the code can be regenerated correctly.
1001 // This check is only needed for access_field_patching since this
1002 // is the path for patching field offsets. load_klass is only
1003 // used for patching references to oops which don't need special
1004 // handling in the volatile case.
1005
1006 deoptimize_for_volatile = result.access_flags().is_volatile();
1007
1008 // If we are patching a field which should be atomic, then
1009 // the generated code is not correct either, force deoptimizing.
1010 // We need to only cover T_LONG and T_DOUBLE fields, as we can
1011 // break access atomicity only for them.
1012
1013 // Strictly speaking, the deoptimization on 64-bit platforms
1014 // is unnecessary, and T_LONG stores on 32-bit platforms need
1015 // to be handled by special patching code when AlwaysAtomicAccesses
1016 // becomes product feature. At this point, we are still going
1017 // for the deoptimization for consistency against volatile
1018 // accesses.
1019
1020 patch_field_type = result.field_type();
1021 deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
1022
1023 } else if (load_klass_or_mirror_patch_id) {
1024 Klass* k = nullptr;
1025 switch (code) {
1026 case Bytecodes::_putstatic:
1027 case Bytecodes::_getstatic:
1028 { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
1029 init_klass = klass;
1030 mirror = Handle(current, klass->java_mirror());
1031 }
1032 break;
1033 case Bytecodes::_new:
1034 { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
1035 k = caller_method->constants()->klass_at(bnew.index(), CHECK);
1036 }
1037 break;
1038 case Bytecodes::_multianewarray:
1039 { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
1040 k = caller_method->constants()->klass_at(mna.index(), CHECK);
1041 }
1042 break;
1043 case Bytecodes::_instanceof:
1044 { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
1045 k = caller_method->constants()->klass_at(io.index(), CHECK);
1046 }
1047 break;
1048 case Bytecodes::_checkcast:
1049 { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
1050 k = caller_method->constants()->klass_at(cc.index(), CHECK);
1051 }
1052 break;
1053 case Bytecodes::_anewarray:
1054 { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
1055 Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
1056 k = ek->array_klass(CHECK);
1057 }
1058 break;
1059 case Bytecodes::_ldc:
1060 case Bytecodes::_ldc_w:
1061 case Bytecodes::_ldc2_w:
1062 {
1063 Bytecode_loadconstant cc(caller_method, bci);
1064 oop m = cc.resolve_constant(CHECK);
1065 mirror = Handle(current, m);
1066 }
1067 break;
1068 default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
1069 }
1070 load_klass = k;
1071 } else if (stub_id == StubId::c1_load_appendix_patching_id) {
1072 Bytecode_invoke bytecode(caller_method, bci);
1073 Bytecodes::Code bc = bytecode.invoke_code();
1074
1075 CallInfo info;
1076 constantPoolHandle pool(current, caller_method->constants());
1077 int index = bytecode.index();
1078 LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
1079 switch (bc) {
1080 case Bytecodes::_invokehandle: {
1081 ResolvedMethodEntry* entry = pool->cache()->set_method_handle(index, info);
1082 appendix = Handle(current, pool->cache()->appendix_if_resolved(entry));
1083 break;
1084 }
1085 case Bytecodes::_invokedynamic: {
1086 appendix = Handle(current, pool->cache()->set_dynamic_call(info, index));
1087 break;
1088 }
1089 default: fatal("unexpected bytecode for load_appendix_patching_id");
1090 }
1091 } else {
1092 ShouldNotReachHere();
1093 }
1094
1095 if (deoptimize_for_volatile || deoptimize_for_atomic) {
1096 // At compile time we assumed the field wasn't volatile/atomic but after
1097 // loading it turns out it was volatile/atomic so we have to throw the
1098 // compiled code out and let it be regenerated.
1099 if (TracePatching) {
1100 if (deoptimize_for_volatile) {
1101 tty->print_cr("Deoptimizing for patching volatile field reference");
1102 }
1103 if (deoptimize_for_atomic) {
1104 tty->print_cr("Deoptimizing for patching atomic field reference");
1105 }
1106 }
1107
1108 // It's possible the nmethod was invalidated in the last
1109 // safepoint, but if it's still alive then make it not_entrant.
1110 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1111 if (nm != nullptr) {
1112 nm->make_not_entrant(nmethod::InvalidationReason::C1_CODEPATCH);
1113 }
1114
1115 Deoptimization::deoptimize_frame(current, caller_frame.id());
1116
1117 // Return to the now deoptimized frame.
1118 }
1119
1120 // Now copy code back
1121
1122 {
1123 MutexLocker ml_code (current, CodeCache_lock, Mutex::_no_safepoint_check_flag);
1124 //
1125 // Deoptimization may have happened while we waited for the lock.
1126 // In that case we don't bother to do any patching we just return
1127 // and let the deopt happen
1128 if (!caller_is_deopted(current)) {
1129 NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
1130 address instr_pc = jump->jump_destination();
1131 NativeInstruction* ni = nativeInstruction_at(instr_pc);
1132 if (ni->is_jump() ) {
1133 // the jump has not been patched yet
1134 // The jump destination is slow case and therefore not part of the stubs
1135 // (stubs are only for StaticCalls)
1136
1137 // format of buffer
1138 // ....
1139 // instr byte 0 <-- copy_buff
1140 // instr byte 1
1141 // ..
1142 // instr byte n-1
1143 // n
1144 // .... <-- call destination
1145
1146 address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
1147 unsigned char* byte_count = (unsigned char*) (stub_location - 1);
1148 unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
1149 unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
1150 address copy_buff = stub_location - *byte_skip - *byte_count;
1151 address being_initialized_entry = stub_location - *being_initialized_entry_offset;
1152 if (TracePatching) {
1153 ttyLocker ttyl;
1154 tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT " (%s)", Bytecodes::name(code), bci,
1155 p2i(instr_pc), (stub_id == StubId::c1_access_field_patching_id) ? "field" : "klass");
1156 nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
1157 assert(caller_code != nullptr, "nmethod not found");
1158
1159 // NOTE we use pc() not original_pc() because we already know they are
1160 // identical otherwise we'd have never entered this block of code
1161
1162 const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
1163 assert(map != nullptr, "null check");
1164 map->print();
1165 tty->cr();
1166
1167 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1168 }
1169 // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
1170 bool do_patch = true;
1171 if (stub_id == StubId::c1_access_field_patching_id) {
1172 // The offset may not be correct if the class was not loaded at code generation time.
1173 // Set it now.
1174 NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
1175 assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1176 assert(patch_field_offset >= 0, "illegal offset");
1177 n_move->add_offset_in_bytes(patch_field_offset);
1178 } else if (load_klass_or_mirror_patch_id) {
1179 // If a getstatic or putstatic is referencing a klass which
1180 // isn't fully initialized, the patch body isn't copied into
1181 // place until initialization is complete. In this case the
1182 // patch site is setup so that any threads besides the
1183 // initializing thread are forced to come into the VM and
1184 // block.
1185 do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1186 InstanceKlass::cast(init_klass)->is_initialized();
1187 NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1188 if (jump->jump_destination() == being_initialized_entry) {
1189 assert(do_patch == true, "initialization must be complete at this point");
1190 } else {
1191 // patch the instruction <move reg, klass>
1192 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1193
1194 assert(n_copy->data() == 0 ||
1195 n_copy->data() == (intptr_t)Universe::non_oop_word(),
1196 "illegal init value");
1197 if (stub_id == StubId::c1_load_klass_patching_id) {
1198 assert(load_klass != nullptr, "klass not set");
1199 n_copy->set_data((intx) (load_klass));
1200 } else {
1201 // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1202 n_copy->set_data(cast_from_oop<intx>(mirror()));
1203 }
1204
1205 if (TracePatching) {
1206 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1207 }
1208 }
1209 } else if (stub_id == StubId::c1_load_appendix_patching_id) {
1210 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1211 assert(n_copy->data() == 0 ||
1212 n_copy->data() == (intptr_t)Universe::non_oop_word(),
1213 "illegal init value");
1214 n_copy->set_data(cast_from_oop<intx>(appendix()));
1215
1216 if (TracePatching) {
1217 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1218 }
1219 } else {
1220 ShouldNotReachHere();
1221 }
1222
1223 if (do_patch) {
1224 // replace instructions
1225 // first replace the tail, then the call
1226 #ifdef ARM
1227 if((load_klass_or_mirror_patch_id ||
1228 stub_id == StubId::c1_load_appendix_patching_id) &&
1229 nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1230 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1231 address addr = nullptr;
1232 assert(nm != nullptr, "invalid nmethod_pc");
1233 RelocIterator mds(nm, copy_buff, copy_buff + 1);
1234 while (mds.next()) {
1235 if (mds.type() == relocInfo::oop_type) {
1236 assert(stub_id == StubId::c1_load_mirror_patching_id ||
1237 stub_id == StubId::c1_load_appendix_patching_id, "wrong stub id");
1238 oop_Relocation* r = mds.oop_reloc();
1239 addr = (address)r->oop_addr();
1240 break;
1241 } else if (mds.type() == relocInfo::metadata_type) {
1242 assert(stub_id == StubId::c1_load_klass_patching_id, "wrong stub id");
1243 metadata_Relocation* r = mds.metadata_reloc();
1244 addr = (address)r->metadata_addr();
1245 break;
1246 }
1247 }
1248 assert(addr != nullptr, "metadata relocation must exist");
1249 copy_buff -= *byte_count;
1250 NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1251 n_copy2->set_pc_relative_offset(addr, instr_pc);
1252 }
1253 #endif
1254
1255 for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
1256 address ptr = copy_buff + i;
1257 int a_byte = (*ptr) & 0xFF;
1258 address dst = instr_pc + i;
1259 *(unsigned char*)dst = (unsigned char) a_byte;
1260 }
1261 ICache::invalidate_range(instr_pc, *byte_count);
1262 NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1263
1264 if (load_klass_or_mirror_patch_id ||
1265 stub_id == StubId::c1_load_appendix_patching_id) {
1266 relocInfo::relocType rtype =
1267 (stub_id == StubId::c1_load_klass_patching_id) ?
1268 relocInfo::metadata_type :
1269 relocInfo::oop_type;
1270 // update relocInfo to metadata
1271 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1272 assert(nm != nullptr, "invalid nmethod_pc");
1273
1274 // The old patch site is now a move instruction so update
1275 // the reloc info so that it will get updated during
1276 // future GCs.
1277 RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1278 relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1279 relocInfo::none, rtype);
1280 }
1281
1282 } else {
1283 ICache::invalidate_range(copy_buff, *byte_count);
1284 NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1285 }
1286 }
1287 }
1288 // If we are patching in a non-perm oop, make sure the nmethod
1289 // is on the right list.
1290 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1291 guarantee(nm != nullptr, "only nmethods can contain non-perm oops");
1292
1293 // Since we've patched some oops in the nmethod,
1294 // (re)register it with the heap.
1295 Universe::heap()->register_nmethod(nm);
1296 }
1297 JRT_END
1298
1299 #else // DEOPTIMIZE_WHEN_PATCHING
1300
1301 static bool is_patching_needed(JavaThread* current, StubId stub_id) {
1302 if (stub_id == StubId::c1_load_klass_patching_id ||
1303 stub_id == StubId::c1_load_mirror_patching_id) {
1304 // last java frame on stack
1305 vframeStream vfst(current, true);
1306 assert(!vfst.at_end(), "Java frame must exist");
1307
1308 methodHandle caller_method(current, vfst.method());
1309 int bci = vfst.bci();
1310 Bytecodes::Code code = caller_method()->java_code_at(bci);
1311
1312 switch (code) {
1313 case Bytecodes::_new:
1314 case Bytecodes::_anewarray:
1315 case Bytecodes::_multianewarray:
1316 case Bytecodes::_instanceof:
1317 case Bytecodes::_checkcast: {
1318 Bytecode bc(caller_method(), caller_method->bcp_from(bci));
1319 constantTag tag = caller_method->constants()->tag_at(bc.get_index_u2(code));
1320 if (tag.is_unresolved_klass_in_error()) {
1321 return false; // throws resolution error
1322 }
1323 break;
1324 }
1325
1326 default: break;
1327 }
1328 }
1329 return true;
1330 }
1331
1332 void Runtime1::patch_code(JavaThread* current, StubId stub_id) {
1333 #ifndef PRODUCT
1334 if (PrintC1Statistics) {
1335 _patch_code_slowcase_cnt++;
1336 }
1337 #endif
1338
1339 // Enable WXWrite: the function is called by c1 stub as a runtime function
1340 // (see another implementation above).
1341 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
1342
1343 if (TracePatching) {
1344 tty->print_cr("Deoptimizing because patch is needed");
1345 }
1346
1347 RegisterMap reg_map(current,
1348 RegisterMap::UpdateMap::skip,
1349 RegisterMap::ProcessFrames::include,
1350 RegisterMap::WalkContinuation::skip);
1351
1352 frame runtime_frame = current->last_frame();
1353 frame caller_frame = runtime_frame.sender(®_map);
1354 assert(caller_frame.is_compiled_frame(), "Wrong frame type");
1355
1356 if (is_patching_needed(current, stub_id)) {
1357 // Make sure the nmethod is invalidated, i.e. made not entrant.
1358 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1359 if (nm != nullptr) {
1360 nm->make_not_entrant(nmethod::InvalidationReason::C1_DEOPTIMIZE_FOR_PATCHING);
1361 }
1362 }
1363
1364 Deoptimization::deoptimize_frame(current, caller_frame.id());
1365 // Return to the now deoptimized frame.
1366 postcond(caller_is_deopted(current));
1367 }
1368
1369 #endif // DEOPTIMIZE_WHEN_PATCHING
1370
1371 // Entry point for compiled code. We want to patch a nmethod.
1372 // We don't do a normal VM transition here because we want to
1373 // know after the patching is complete and any safepoint(s) are taken
1374 // if the calling nmethod was deoptimized. We do this by calling a
1375 // helper method which does the normal VM transition and when it
1376 // completes we can check for deoptimization. This simplifies the
1377 // assembly code in the cpu directories.
1378 //
1379 int Runtime1::move_klass_patching(JavaThread* current) {
1380 //
1381 // NOTE: we are still in Java
1382 //
1383 DEBUG_ONLY(NoHandleMark nhm;)
1384 {
1385 // Enter VM mode
1386 ResetNoHandleMark rnhm;
1387 patch_code(current, StubId::c1_load_klass_patching_id);
1388 }
1389 // Back in JAVA, use no oops DON'T safepoint
1390
1391 // Return true if calling code is deoptimized
1392
1393 return caller_is_deopted(current);
1394 }
1395
1396 int Runtime1::move_mirror_patching(JavaThread* current) {
1397 //
1398 // NOTE: we are still in Java
1399 //
1400 DEBUG_ONLY(NoHandleMark nhm;)
1401 {
1402 // Enter VM mode
1403 ResetNoHandleMark rnhm;
1404 patch_code(current, StubId::c1_load_mirror_patching_id);
1405 }
1406 // Back in JAVA, use no oops DON'T safepoint
1407
1408 // Return true if calling code is deoptimized
1409
1410 return caller_is_deopted(current);
1411 }
1412
1413 int Runtime1::move_appendix_patching(JavaThread* current) {
1414 //
1415 // NOTE: we are still in Java
1416 //
1417 DEBUG_ONLY(NoHandleMark nhm;)
1418 {
1419 // Enter VM mode
1420 ResetNoHandleMark rnhm;
1421 patch_code(current, StubId::c1_load_appendix_patching_id);
1422 }
1423 // Back in JAVA, use no oops DON'T safepoint
1424
1425 // Return true if calling code is deoptimized
1426
1427 return caller_is_deopted(current);
1428 }
1429
1430 // Entry point for compiled code. We want to patch a nmethod.
1431 // We don't do a normal VM transition here because we want to
1432 // know after the patching is complete and any safepoint(s) are taken
1433 // if the calling nmethod was deoptimized. We do this by calling a
1434 // helper method which does the normal VM transition and when it
1435 // completes we can check for deoptimization. This simplifies the
1436 // assembly code in the cpu directories.
1437 //
1438 int Runtime1::access_field_patching(JavaThread* current) {
1439 //
1440 // NOTE: we are still in Java
1441 //
1442 // Handles created in this function will be deleted by the
1443 // HandleMarkCleaner in the transition to the VM.
1444 NoHandleMark nhm;
1445 {
1446 // Enter VM mode
1447 ResetNoHandleMark rnhm;
1448 patch_code(current, StubId::c1_access_field_patching_id);
1449 }
1450 // Back in JAVA, use no oops DON'T safepoint
1451
1452 // Return true if calling code is deoptimized
1453
1454 return caller_is_deopted(current);
1455 }
1456
1457
1458 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1459 // for now we just print out the block id
1460 tty->print("%d ", block_id);
1461 JRT_END
1462
1463
1464 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1465 // had to return int instead of bool, otherwise there may be a mismatch
1466 // between the C calling convention and the Java one.
1467 // e.g., on x86, GCC may clear only %al when returning a bool false, but
1468 // JVM takes the whole %eax as the return value, which may misinterpret
1469 // the return value as a boolean true.
1470
1471 assert(mirror != nullptr, "should null-check on mirror before calling");
1472 Klass* k = java_lang_Class::as_Klass(mirror);
1473 return (k != nullptr && obj != nullptr && obj->is_a(k)) ? 1 : 0;
1474 JRT_END
1475
1476 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* current))
1477 ResourceMark rm;
1478
1479 RegisterMap reg_map(current,
1480 RegisterMap::UpdateMap::skip,
1481 RegisterMap::ProcessFrames::include,
1482 RegisterMap::WalkContinuation::skip);
1483 frame runtime_frame = current->last_frame();
1484 frame caller_frame = runtime_frame.sender(®_map);
1485
1486 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1487 assert (nm != nullptr, "no more nmethod?");
1488 nm->make_not_entrant(nmethod::InvalidationReason::C1_PREDICATE_FAILED_TRAP);
1489
1490 methodHandle m(current, nm->method());
1491 MethodData* mdo = m->method_data();
1492
1493 if (mdo == nullptr && !HAS_PENDING_EXCEPTION) {
1494 // Build an MDO. Ignore errors like OutOfMemory;
1495 // that simply means we won't have an MDO to update.
1496 Method::build_profiling_method_data(m, THREAD);
1497 if (HAS_PENDING_EXCEPTION) {
1498 // Only metaspace OOM is expected. No Java code executed.
1499 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1500 CLEAR_PENDING_EXCEPTION;
1501 }
1502 mdo = m->method_data();
1503 }
1504
1505 if (mdo != nullptr) {
1506 mdo->inc_trap_count(Deoptimization::Reason_none);
1507 }
1508
1509 if (TracePredicateFailedTraps) {
1510 stringStream ss1, ss2;
1511 vframeStream vfst(current);
1512 Method* inlinee = vfst.method();
1513 inlinee->print_short_name(&ss1);
1514 m->print_short_name(&ss2);
1515 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()));
1516 }
1517
1518
1519 Deoptimization::deoptimize_frame(current, caller_frame.id());
1520
1521 JRT_END
1522
1523 // Check exception if AbortVMOnException flag set
1524 JRT_LEAF(void, Runtime1::check_abort_on_vm_exception(oopDesc* ex))
1525 ResourceMark rm;
1526 const char* message = nullptr;
1527 if (ex->is_a(vmClasses::Throwable_klass())) {
1528 oop msg = java_lang_Throwable::message(ex);
1529 if (msg != nullptr) {
1530 message = java_lang_String::as_utf8_string(msg);
1531 }
1532 }
1533 Exceptions::debug_check_abort(ex->klass()->external_name(), message);
1534 JRT_END
1535
1536 #ifndef PRODUCT
1537 void Runtime1::print_statistics() {
1538 tty->print_cr("C1 Runtime statistics:");
1539 tty->print_cr(" _resolve_invoke_virtual_cnt: %u", SharedRuntime::_resolve_virtual_ctr);
1540 tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %u", SharedRuntime::_resolve_opt_virtual_ctr);
1541 tty->print_cr(" _resolve_invoke_static_cnt: %u", SharedRuntime::_resolve_static_ctr);
1542 tty->print_cr(" _handle_wrong_method_cnt: %u", SharedRuntime::_wrong_method_ctr);
1543 tty->print_cr(" _ic_miss_cnt: %u", SharedRuntime::_ic_miss_ctr);
1544 tty->print_cr(" _generic_arraycopystub_cnt: %u", _generic_arraycopystub_cnt);
1545 tty->print_cr(" _byte_arraycopy_cnt: %u", _byte_arraycopy_stub_cnt);
1546 tty->print_cr(" _short_arraycopy_cnt: %u", _short_arraycopy_stub_cnt);
1547 tty->print_cr(" _int_arraycopy_cnt: %u", _int_arraycopy_stub_cnt);
1548 tty->print_cr(" _long_arraycopy_cnt: %u", _long_arraycopy_stub_cnt);
1549 tty->print_cr(" _oop_arraycopy_cnt: %u", _oop_arraycopy_stub_cnt);
1550 tty->print_cr(" _arraycopy_slowcase_cnt: %u", _arraycopy_slowcase_cnt);
1551 tty->print_cr(" _arraycopy_checkcast_cnt: %u", _arraycopy_checkcast_cnt);
1552 tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%u", _arraycopy_checkcast_attempt_cnt);
1553
1554 tty->print_cr(" _new_type_array_slowcase_cnt: %u", _new_type_array_slowcase_cnt);
1555 tty->print_cr(" _new_object_array_slowcase_cnt: %u", _new_object_array_slowcase_cnt);
1556 tty->print_cr(" _new_instance_slowcase_cnt: %u", _new_instance_slowcase_cnt);
1557 tty->print_cr(" _new_multi_array_slowcase_cnt: %u", _new_multi_array_slowcase_cnt);
1558 tty->print_cr(" _monitorenter_slowcase_cnt: %u", _monitorenter_slowcase_cnt);
1559 tty->print_cr(" _monitorexit_slowcase_cnt: %u", _monitorexit_slowcase_cnt);
1560 tty->print_cr(" _patch_code_slowcase_cnt: %u", _patch_code_slowcase_cnt);
1561
1562 tty->print_cr(" _throw_range_check_exception_count: %u:", _throw_range_check_exception_count);
1563 tty->print_cr(" _throw_index_exception_count: %u:", _throw_index_exception_count);
1564 tty->print_cr(" _throw_div0_exception_count: %u:", _throw_div0_exception_count);
1565 tty->print_cr(" _throw_null_pointer_exception_count: %u:", _throw_null_pointer_exception_count);
1566 tty->print_cr(" _throw_class_cast_exception_count: %u:", _throw_class_cast_exception_count);
1567 tty->print_cr(" _throw_incompatible_class_change_error_count: %u:", _throw_incompatible_class_change_error_count);
1568 tty->print_cr(" _throw_count: %u:", _throw_count);
1569
1570 SharedRuntime::print_ic_miss_histogram();
1571 tty->cr();
1572 }
1573 #endif // PRODUCT