1 /*
2 * Copyright (c) 1999, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "asm/codeBuffer.hpp"
27 #include "c1/c1_CodeStubs.hpp"
28 #include "c1/c1_Defs.hpp"
29 #include "c1/c1_FrameMap.hpp"
30 #include "c1/c1_LIRAssembler.hpp"
31 #include "c1/c1_MacroAssembler.hpp"
32 #include "c1/c1_Runtime1.hpp"
33 #include "classfile/javaClasses.inline.hpp"
34 #include "classfile/vmClasses.hpp"
35 #include "classfile/vmSymbols.hpp"
36 #include "code/codeBlob.hpp"
37 #include "code/compiledIC.hpp"
38 #include "code/pcDesc.hpp"
39 #include "code/scopeDesc.hpp"
40 #include "code/vtableStubs.hpp"
41 #include "compiler/compilationPolicy.hpp"
42 #include "compiler/disassembler.hpp"
43 #include "compiler/oopMap.hpp"
44 #include "gc/shared/barrierSet.hpp"
45 #include "gc/shared/c1/barrierSetC1.hpp"
46 #include "gc/shared/collectedHeap.hpp"
47 #include "interpreter/bytecode.hpp"
48 #include "interpreter/interpreter.hpp"
49 #include "jfr/support/jfrIntrinsics.hpp"
50 #include "logging/log.hpp"
51 #include "memory/allocation.inline.hpp"
52 #include "memory/oopFactory.hpp"
53 #include "memory/resourceArea.hpp"
54 #include "memory/universe.hpp"
55 #include "oops/access.inline.hpp"
56 #include "oops/klass.inline.hpp"
57 #include "oops/objArrayOop.inline.hpp"
58 #include "oops/objArrayKlass.hpp"
59 #include "oops/oop.inline.hpp"
60 #include "prims/jvmtiExport.hpp"
61 #include "runtime/atomic.hpp"
62 #include "runtime/fieldDescriptor.inline.hpp"
63 #include "runtime/frame.inline.hpp"
64 #include "runtime/handles.inline.hpp"
65 #include "runtime/interfaceSupport.inline.hpp"
66 #include "runtime/javaCalls.hpp"
67 #include "runtime/sharedRuntime.hpp"
68 #include "runtime/stackWatermarkSet.hpp"
69 #include "runtime/stubRoutines.hpp"
70 #include "runtime/threadCritical.hpp"
71 #include "runtime/vframe.inline.hpp"
72 #include "runtime/vframeArray.hpp"
73 #include "runtime/vm_version.hpp"
74 #include "utilities/copy.hpp"
75 #include "utilities/events.hpp"
76 #include "utilities/macros.hpp"
77
78
79 // Implementation of StubAssembler
80
81 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
82 _name = name;
83 _must_gc_arguments = false;
84 _frame_size = no_frame_size;
85 _num_rt_args = 0;
86 _stub_id = stub_id;
87 }
88
89
90 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
91 _name = name;
92 _must_gc_arguments = must_gc_arguments;
93 }
94
95
96 void StubAssembler::set_frame_size(int size) {
97 if (_frame_size == no_frame_size) {
98 _frame_size = size;
99 }
100 assert(_frame_size == size, "can't change the frame size");
101 }
102
103
104 void StubAssembler::set_num_rt_args(int args) {
105 if (_num_rt_args == 0) {
106 _num_rt_args = args;
107 }
108 assert(_num_rt_args == args, "can't change the number of args");
109 }
110
111 // Implementation of Runtime1
112
113 CodeBlob* Runtime1::_blobs[Runtime1::number_of_ids];
114 const char *Runtime1::_blob_names[] = {
115 RUNTIME1_STUBS(STUB_NAME, LAST_STUB_NAME)
116 };
117
118 #ifndef PRODUCT
119 // statistics
120 uint Runtime1::_generic_arraycopystub_cnt = 0;
121 uint Runtime1::_arraycopy_slowcase_cnt = 0;
122 uint Runtime1::_arraycopy_checkcast_cnt = 0;
123 uint Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
124 uint Runtime1::_new_type_array_slowcase_cnt = 0;
125 uint Runtime1::_new_object_array_slowcase_cnt = 0;
126 uint Runtime1::_new_instance_slowcase_cnt = 0;
127 uint Runtime1::_new_multi_array_slowcase_cnt = 0;
128 uint Runtime1::_monitorenter_slowcase_cnt = 0;
129 uint Runtime1::_monitorexit_slowcase_cnt = 0;
130 uint Runtime1::_patch_code_slowcase_cnt = 0;
131 uint Runtime1::_throw_range_check_exception_count = 0;
132 uint Runtime1::_throw_index_exception_count = 0;
133 uint Runtime1::_throw_div0_exception_count = 0;
134 uint Runtime1::_throw_null_pointer_exception_count = 0;
135 uint Runtime1::_throw_class_cast_exception_count = 0;
136 uint Runtime1::_throw_incompatible_class_change_error_count = 0;
137 uint Runtime1::_throw_count = 0;
138
139 static uint _byte_arraycopy_stub_cnt = 0;
140 static uint _short_arraycopy_stub_cnt = 0;
141 static uint _int_arraycopy_stub_cnt = 0;
142 static uint _long_arraycopy_stub_cnt = 0;
143 static uint _oop_arraycopy_stub_cnt = 0;
144
145 address Runtime1::arraycopy_count_address(BasicType type) {
146 switch (type) {
147 case T_BOOLEAN:
148 case T_BYTE: return (address)&_byte_arraycopy_stub_cnt;
149 case T_CHAR:
150 case T_SHORT: return (address)&_short_arraycopy_stub_cnt;
151 case T_FLOAT:
152 case T_INT: return (address)&_int_arraycopy_stub_cnt;
153 case T_DOUBLE:
154 case T_LONG: return (address)&_long_arraycopy_stub_cnt;
155 case T_ARRAY:
156 case T_OBJECT: return (address)&_oop_arraycopy_stub_cnt;
157 default:
158 ShouldNotReachHere();
159 return nullptr;
160 }
161 }
162
163
164 #endif
165
166 // Simple helper to see if the caller of a runtime stub which
167 // entered the VM has been deoptimized
168
169 static bool caller_is_deopted(JavaThread* current) {
170 RegisterMap reg_map(current,
171 RegisterMap::UpdateMap::skip,
172 RegisterMap::ProcessFrames::include,
173 RegisterMap::WalkContinuation::skip);
174 frame runtime_frame = current->last_frame();
175 frame caller_frame = runtime_frame.sender(®_map);
176 assert(caller_frame.is_compiled_frame(), "must be compiled");
177 return caller_frame.is_deoptimized_frame();
178 }
179
180 // Stress deoptimization
181 static void deopt_caller(JavaThread* current) {
182 if (!caller_is_deopted(current)) {
183 RegisterMap reg_map(current,
184 RegisterMap::UpdateMap::skip,
185 RegisterMap::ProcessFrames::include,
186 RegisterMap::WalkContinuation::skip);
187 frame runtime_frame = current->last_frame();
188 frame caller_frame = runtime_frame.sender(®_map);
189 Deoptimization::deoptimize_frame(current, caller_frame.id());
190 assert(caller_is_deopted(current), "Must be deoptimized");
191 }
192 }
193
194 class StubIDStubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
195 private:
196 Runtime1::StubID _id;
197 public:
198 StubIDStubAssemblerCodeGenClosure(Runtime1::StubID id) : _id(id) {}
199 virtual OopMapSet* generate_code(StubAssembler* sasm) {
200 return Runtime1::generate_code_for(_id, sasm);
201 }
202 };
203
204 CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, int stub_id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
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, stub_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 assert(blob != nullptr, "blob must exist");
238 return blob;
239 }
240
241 void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
242 assert(0 <= id && id < number_of_ids, "illegal stub id");
243 bool expect_oop_map = true;
244 #ifdef ASSERT
245 // Make sure that stubs that need oopmaps have them
246 switch (id) {
247 // These stubs don't need to have an oopmap
248 case dtrace_object_alloc_id:
249 case slow_subtype_check_id:
250 case fpu2long_stub_id:
251 case unwind_exception_id:
252 case counter_overflow_id:
253 expect_oop_map = false;
254 break;
255 default:
256 break;
257 }
258 #endif
259 StubIDStubAssemblerCodeGenClosure cl(id);
260 CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
261 // install blob
262 _blobs[id] = blob;
263 }
264
265 void Runtime1::initialize(BufferBlob* blob) {
266 // platform-dependent initialization
267 initialize_pd();
268 // generate stubs
269 for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
270 // printing
271 #ifndef PRODUCT
272 if (PrintSimpleStubs) {
273 ResourceMark rm;
274 for (int id = 0; id < number_of_ids; id++) {
275 _blobs[id]->print();
276 if (_blobs[id]->oop_maps() != nullptr) {
277 _blobs[id]->oop_maps()->print();
278 }
279 }
280 }
281 #endif
282 BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
283 bs->generate_c1_runtime_stubs(blob);
284 }
285
286 CodeBlob* Runtime1::blob_for(StubID id) {
287 assert(0 <= id && id < number_of_ids, "illegal stub id");
288 return _blobs[id];
289 }
290
291
292 const char* Runtime1::name_for(StubID id) {
293 assert(0 <= id && id < number_of_ids, "illegal stub id");
294 return _blob_names[id];
295 }
296
297 const char* Runtime1::name_for_address(address entry) {
298 for (int id = 0; id < number_of_ids; id++) {
299 if (entry == entry_for((StubID)id)) return name_for((StubID)id);
300 }
301
302 #define FUNCTION_CASE(a, f) \
303 if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f)) return #f
304
305 FUNCTION_CASE(entry, os::javaTimeMillis);
306 FUNCTION_CASE(entry, os::javaTimeNanos);
307 FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
308 FUNCTION_CASE(entry, SharedRuntime::d2f);
309 FUNCTION_CASE(entry, SharedRuntime::d2i);
310 FUNCTION_CASE(entry, SharedRuntime::d2l);
311 FUNCTION_CASE(entry, SharedRuntime::dcos);
312 FUNCTION_CASE(entry, SharedRuntime::dexp);
313 FUNCTION_CASE(entry, SharedRuntime::dlog);
314 FUNCTION_CASE(entry, SharedRuntime::dlog10);
315 FUNCTION_CASE(entry, SharedRuntime::dpow);
316 FUNCTION_CASE(entry, SharedRuntime::drem);
317 FUNCTION_CASE(entry, SharedRuntime::dsin);
318 FUNCTION_CASE(entry, SharedRuntime::dtan);
319 FUNCTION_CASE(entry, SharedRuntime::f2i);
320 FUNCTION_CASE(entry, SharedRuntime::f2l);
321 FUNCTION_CASE(entry, SharedRuntime::frem);
322 FUNCTION_CASE(entry, SharedRuntime::l2d);
323 FUNCTION_CASE(entry, SharedRuntime::l2f);
324 FUNCTION_CASE(entry, SharedRuntime::ldiv);
325 FUNCTION_CASE(entry, SharedRuntime::lmul);
326 FUNCTION_CASE(entry, SharedRuntime::lrem);
327 FUNCTION_CASE(entry, SharedRuntime::lrem);
328 FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
329 FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
330 FUNCTION_CASE(entry, is_instance_of);
331 FUNCTION_CASE(entry, trace_block_entry);
332 #ifdef JFR_HAVE_INTRINSICS
333 FUNCTION_CASE(entry, JfrTime::time_function());
334 #endif
335 FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
336 FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
337 FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
338 FUNCTION_CASE(entry, StubRoutines::dexp());
339 FUNCTION_CASE(entry, StubRoutines::dlog());
340 FUNCTION_CASE(entry, StubRoutines::dlog10());
341 FUNCTION_CASE(entry, StubRoutines::dpow());
342 FUNCTION_CASE(entry, StubRoutines::dsin());
343 FUNCTION_CASE(entry, StubRoutines::dcos());
344 FUNCTION_CASE(entry, StubRoutines::dtan());
345
346 #undef FUNCTION_CASE
347
348 // Soft float adds more runtime names.
349 return pd_name_for_address(entry);
350 }
351
352
353 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* current, Klass* klass))
354 #ifndef PRODUCT
355 if (PrintC1Statistics) {
356 _new_instance_slowcase_cnt++;
357 }
358 #endif
359 assert(klass->is_klass(), "not a class");
360 Handle holder(current, klass->klass_holder()); // keep the klass alive
361 InstanceKlass* h = InstanceKlass::cast(klass);
362 h->check_valid_for_instantiation(true, CHECK);
363 // make sure klass is initialized
364 h->initialize(CHECK);
365 // allocate instance and return via TLS
366 oop obj = h->allocate_instance(CHECK);
367 current->set_vm_result(obj);
368 JRT_END
369
370
371 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* current, Klass* klass, jint length))
372 #ifndef PRODUCT
373 if (PrintC1Statistics) {
374 _new_type_array_slowcase_cnt++;
375 }
376 #endif
377 // Note: no handle for klass needed since they are not used
378 // anymore after new_typeArray() and no GC can happen before.
379 // (This may have to change if this code changes!)
380 assert(klass->is_klass(), "not a class");
381 BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
382 oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
383 current->set_vm_result(obj);
384 // This is pretty rare but this runtime patch is stressful to deoptimization
385 // if we deoptimize here so force a deopt to stress the path.
386 if (DeoptimizeALot) {
387 deopt_caller(current);
388 }
389
390 JRT_END
391
392
393 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* current, Klass* array_klass, jint length))
394 #ifndef PRODUCT
395 if (PrintC1Statistics) {
396 _new_object_array_slowcase_cnt++;
397 }
398 #endif
399 // Note: no handle for klass needed since they are not used
400 // anymore after new_objArray() and no GC can happen before.
401 // (This may have to change if this code changes!)
402 assert(array_klass->is_klass(), "not a class");
403 Handle holder(current, array_klass->klass_holder()); // keep the klass alive
404 Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
405 objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
406 current->set_vm_result(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 JRT_END
413
414
415 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* current, Klass* klass, int rank, jint* dims))
416 #ifndef PRODUCT
417 if (PrintC1Statistics) {
418 _new_multi_array_slowcase_cnt++;
419 }
420 #endif
421 assert(klass->is_klass(), "not a class");
422 assert(rank >= 1, "rank must be nonzero");
423 Handle holder(current, klass->klass_holder()); // keep the klass alive
424 oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
425 current->set_vm_result(obj);
426 JRT_END
427
428
429 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* current, StubID id))
430 tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
431 JRT_END
432
433
434 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* current, oopDesc* obj))
435 ResourceMark rm(current);
436 const char* klass_name = obj->klass()->external_name();
437 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayStoreException(), klass_name);
438 JRT_END
439
440
441 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
442 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
443 // method) method is passed as an argument. In order to do that it is embedded in the code as
444 // a constant.
445 static nmethod* counter_overflow_helper(JavaThread* current, int branch_bci, Method* m) {
446 nmethod* osr_nm = nullptr;
447 methodHandle method(current, m);
448
449 RegisterMap map(current,
450 RegisterMap::UpdateMap::skip,
451 RegisterMap::ProcessFrames::include,
452 RegisterMap::WalkContinuation::skip);
453 frame fr = current->last_frame().sender(&map);
454 nmethod* nm = (nmethod*) fr.cb();
455 assert(nm!= nullptr && nm->is_nmethod(), "Sanity check");
456 methodHandle enclosing_method(current, nm->method());
457
458 CompLevel level = (CompLevel)nm->comp_level();
459 int bci = InvocationEntryBci;
460 if (branch_bci != InvocationEntryBci) {
461 // Compute destination bci
462 address pc = method()->code_base() + branch_bci;
463 Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
464 int offset = 0;
465 switch (branch) {
466 case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
467 case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
468 case Bytecodes::_if_icmple: case Bytecodes::_ifle:
469 case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
470 case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
471 case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
472 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
473 offset = (int16_t)Bytes::get_Java_u2(pc + 1);
474 break;
475 case Bytecodes::_goto_w:
476 offset = Bytes::get_Java_u4(pc + 1);
477 break;
478 default: ;
479 }
480 bci = branch_bci + offset;
481 }
482 osr_nm = CompilationPolicy::event(enclosing_method, method, branch_bci, bci, level, nm, current);
483 return osr_nm;
484 }
485
486 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* current, int bci, Method* method))
487 nmethod* osr_nm;
488 JRT_BLOCK
489 osr_nm = counter_overflow_helper(current, bci, method);
490 if (osr_nm != nullptr) {
491 RegisterMap map(current,
492 RegisterMap::UpdateMap::skip,
493 RegisterMap::ProcessFrames::include,
494 RegisterMap::WalkContinuation::skip);
495 frame fr = current->last_frame().sender(&map);
496 Deoptimization::deoptimize_frame(current, fr.id());
497 }
498 JRT_BLOCK_END
499 return nullptr;
500 JRT_END
501
502 extern void vm_exit(int code);
503
504 // Enter this method from compiled code handler below. This is where we transition
505 // to VM mode. This is done as a helper routine so that the method called directly
506 // from compiled code does not have to transition to VM. This allows the entry
507 // method to see if the nmethod that we have just looked up a handler for has
508 // been deoptimized while we were in the vm. This simplifies the assembly code
509 // cpu directories.
510 //
511 // We are entering here from exception stub (via the entry method below)
512 // If there is a compiled exception handler in this method, we will continue there;
513 // otherwise we will unwind the stack and continue at the caller of top frame method
514 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
515 // control the area where we can allow a safepoint. After we exit the safepoint area we can
516 // check to see if the handler we are going to return is now in a nmethod that has
517 // been deoptimized. If that is the case we return the deopt blob
518 // unpack_with_exception entry instead. This makes life for the exception blob easier
519 // because making that same check and diverting is painful from assembly language.
520 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* current, oopDesc* ex, address pc, nmethod*& nm))
521 // Reset method handle flag.
522 current->set_is_method_handle_return(false);
523
524 Handle exception(current, ex);
525
526 // This function is called when we are about to throw an exception. Therefore,
527 // we have to poll the stack watermark barrier to make sure that not yet safe
528 // stack frames are made safe before returning into them.
529 if (current->last_frame().cb() == Runtime1::blob_for(Runtime1::handle_exception_from_callee_id)) {
530 // The Runtime1::handle_exception_from_callee_id handler is invoked after the
531 // frame has been unwound. It instead builds its own stub frame, to call the
532 // runtime. But the throwing frame has already been unwound here.
533 StackWatermarkSet::after_unwind(current);
534 }
535
536 nm = CodeCache::find_nmethod(pc);
537 assert(nm != nullptr, "this is not an nmethod");
538 // Adjust the pc as needed/
539 if (nm->is_deopt_pc(pc)) {
540 RegisterMap map(current,
541 RegisterMap::UpdateMap::skip,
542 RegisterMap::ProcessFrames::include,
543 RegisterMap::WalkContinuation::skip);
544 frame exception_frame = current->last_frame().sender(&map);
545 // if the frame isn't deopted then pc must not correspond to the caller of last_frame
546 assert(exception_frame.is_deoptimized_frame(), "must be deopted");
547 pc = exception_frame.pc();
548 }
549 assert(exception.not_null(), "null exceptions should be handled by throw_exception");
550 // Check that exception is a subclass of Throwable
551 assert(exception->is_a(vmClasses::Throwable_klass()),
552 "Exception not subclass of Throwable");
553
554 // debugging support
555 // tracing
556 if (log_is_enabled(Info, exceptions)) {
557 ResourceMark rm; // print_value_string
558 stringStream tempst;
559 assert(nm->method() != nullptr, "Unexpected null method()");
560 tempst.print("C1 compiled method <%s>\n"
561 " at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
562 nm->method()->print_value_string(), p2i(pc), p2i(current));
563 Exceptions::log_exception(exception, tempst.freeze());
564 }
565 // for AbortVMOnException flag
566 Exceptions::debug_check_abort(exception);
567
568 // Check the stack guard pages and re-enable them if necessary and there is
569 // enough space on the stack to do so. Use fast exceptions only if the guard
570 // pages are enabled.
571 bool guard_pages_enabled = current->stack_overflow_state()->reguard_stack_if_needed();
572
573 if (JvmtiExport::can_post_on_exceptions()) {
574 // To ensure correct notification of exception catches and throws
575 // we have to deoptimize here. If we attempted to notify the
576 // catches and throws during this exception lookup it's possible
577 // we could deoptimize on the way out of the VM and end back in
578 // the interpreter at the throw site. This would result in double
579 // notifications since the interpreter would also notify about
580 // these same catches and throws as it unwound the frame.
581
582 RegisterMap reg_map(current,
583 RegisterMap::UpdateMap::include,
584 RegisterMap::ProcessFrames::include,
585 RegisterMap::WalkContinuation::skip);
586 frame stub_frame = current->last_frame();
587 frame caller_frame = stub_frame.sender(®_map);
588
589 // We don't really want to deoptimize the nmethod itself since we
590 // can actually continue in the exception handler ourselves but I
591 // don't see an easy way to have the desired effect.
592 Deoptimization::deoptimize_frame(current, caller_frame.id());
593 assert(caller_is_deopted(current), "Must be deoptimized");
594
595 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
596 }
597
598 // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
599 if (guard_pages_enabled) {
600 address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
601 if (fast_continuation != nullptr) {
602 // Set flag if return address is a method handle call site.
603 current->set_is_method_handle_return(nm->is_method_handle_return(pc));
604 return fast_continuation;
605 }
606 }
607
608 // If the stack guard pages are enabled, check whether there is a handler in
609 // the current method. Otherwise (guard pages disabled), force an unwind and
610 // skip the exception cache update (i.e., just leave continuation as null).
611 address continuation = nullptr;
612 if (guard_pages_enabled) {
613
614 // New exception handling mechanism can support inlined methods
615 // with exception handlers since the mappings are from PC to PC
616
617 // Clear out the exception oop and pc since looking up an
618 // exception handler can cause class loading, which might throw an
619 // exception and those fields are expected to be clear during
620 // normal bytecode execution.
621 current->clear_exception_oop_and_pc();
622
623 bool recursive_exception = false;
624 continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
625 // If an exception was thrown during exception dispatch, the exception oop may have changed
626 current->set_exception_oop(exception());
627 current->set_exception_pc(pc);
628
629 // the exception cache is used only by non-implicit exceptions
630 // Update the exception cache only when there didn't happen
631 // another exception during the computation of the compiled
632 // exception handler. Checking for exception oop equality is not
633 // sufficient because some exceptions are pre-allocated and reused.
634 if (continuation != nullptr && !recursive_exception) {
635 nm->add_handler_for_exception_and_pc(exception, pc, continuation);
636 }
637 }
638
639 current->set_vm_result(exception());
640 // Set flag if return address is a method handle call site.
641 current->set_is_method_handle_return(nm->is_method_handle_return(pc));
642
643 if (log_is_enabled(Info, exceptions)) {
644 ResourceMark rm;
645 log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
646 " for exception thrown at PC " PTR_FORMAT,
647 p2i(current), p2i(continuation), p2i(pc));
648 }
649
650 return continuation;
651 JRT_END
652
653 // Enter this method from compiled code only if there is a Java exception handler
654 // in the method handling the exception.
655 // We are entering here from exception stub. We don't do a normal VM transition here.
656 // We do it in a helper. This is so we can check to see if the nmethod we have just
657 // searched for an exception handler has been deoptimized in the meantime.
658 address Runtime1::exception_handler_for_pc(JavaThread* current) {
659 oop exception = current->exception_oop();
660 address pc = current->exception_pc();
661 // Still in Java mode
662 DEBUG_ONLY(NoHandleMark nhm);
663 nmethod* nm = nullptr;
664 address continuation = nullptr;
665 {
666 // Enter VM mode by calling the helper
667 ResetNoHandleMark rnhm;
668 continuation = exception_handler_for_pc_helper(current, exception, pc, nm);
669 }
670 // Back in JAVA, use no oops DON'T safepoint
671
672 // Now check to see if the nmethod we were called from is now deoptimized.
673 // If so we must return to the deopt blob and deoptimize the nmethod
674 if (nm != nullptr && caller_is_deopted(current)) {
675 continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
676 }
677
678 assert(continuation != nullptr, "no handler found");
679 return continuation;
680 }
681
682
683 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* current, int index, arrayOopDesc* a))
684 #ifndef PRODUCT
685 if (PrintC1Statistics) {
686 _throw_range_check_exception_count++;
687 }
688 #endif
689 const int len = 35;
690 assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
691 char message[2 * jintAsStringSize + len];
692 os::snprintf_checked(message, sizeof(message), "Index %d out of bounds for length %d", index, a->length());
693 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
694 JRT_END
695
696
697 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* current, int index))
698 #ifndef PRODUCT
699 if (PrintC1Statistics) {
700 _throw_index_exception_count++;
701 }
702 #endif
703 char message[16];
704 os::snprintf_checked(message, sizeof(message), "%d", index);
705 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
706 JRT_END
707
708
709 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* current))
710 #ifndef PRODUCT
711 if (PrintC1Statistics) {
712 _throw_div0_exception_count++;
713 }
714 #endif
715 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
716 JRT_END
717
718
719 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* current))
720 #ifndef PRODUCT
721 if (PrintC1Statistics) {
722 _throw_null_pointer_exception_count++;
723 }
724 #endif
725 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_NullPointerException());
726 JRT_END
727
728
729 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* current, oopDesc* object))
730 #ifndef PRODUCT
731 if (PrintC1Statistics) {
732 _throw_class_cast_exception_count++;
733 }
734 #endif
735 ResourceMark rm(current);
736 char* message = SharedRuntime::generate_class_cast_message(current, object->klass());
737 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ClassCastException(), message);
738 JRT_END
739
740
741 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* current))
742 #ifndef PRODUCT
743 if (PrintC1Statistics) {
744 _throw_incompatible_class_change_error_count++;
745 }
746 #endif
747 ResourceMark rm(current);
748 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IncompatibleClassChangeError());
749 JRT_END
750
751
752 JRT_BLOCK_ENTRY(void, Runtime1::monitorenter(JavaThread* current, oopDesc* obj, BasicObjectLock* lock))
753 #ifndef PRODUCT
754 if (PrintC1Statistics) {
755 _monitorenter_slowcase_cnt++;
756 }
757 #endif
758 if (LockingMode == LM_MONITOR) {
759 lock->set_obj(obj);
760 }
761 assert(obj == lock->obj(), "must match: " PTR_FORMAT, p2i(lock));
762 SharedRuntime::monitor_enter_helper(obj, lock->lock(), current);
763 JRT_END
764
765
766 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* current, BasicObjectLock* lock))
767 assert(current == JavaThread::current(), "pre-condition");
768 #ifndef PRODUCT
769 if (PrintC1Statistics) {
770 _monitorexit_slowcase_cnt++;
771 }
772 #endif
773 assert(current->last_Java_sp(), "last_Java_sp must be set");
774 oop obj = lock->obj();
775 assert(oopDesc::is_oop(obj), "must be null or an object");
776 SharedRuntime::monitor_exit_helper(obj, lock->lock(), current);
777 JRT_END
778
779 // Cf. OptoRuntime::deoptimize_caller_frame
780 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* current, jint trap_request))
781 // Called from within the owner thread, so no need for safepoint
782 RegisterMap reg_map(current,
783 RegisterMap::UpdateMap::skip,
784 RegisterMap::ProcessFrames::include,
785 RegisterMap::WalkContinuation::skip);
786 frame stub_frame = current->last_frame();
787 assert(stub_frame.is_runtime_frame(), "Sanity check");
788 frame caller_frame = stub_frame.sender(®_map);
789 nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
790 assert(nm != nullptr, "Sanity check");
791 methodHandle method(current, nm->method());
792 assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
793 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
794 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
795
796 if (action == Deoptimization::Action_make_not_entrant) {
797 if (nm->make_not_entrant()) {
798 if (reason == Deoptimization::Reason_tenured) {
799 MethodData* trap_mdo = Deoptimization::get_method_data(current, method, true /*create_if_missing*/);
800 if (trap_mdo != nullptr) {
801 trap_mdo->inc_tenure_traps();
802 }
803 }
804 }
805 }
806
807 // Deoptimize the caller frame.
808 Deoptimization::deoptimize_frame(current, caller_frame.id());
809 // Return to the now deoptimized frame.
810 JRT_END
811
812
813 #ifndef DEOPTIMIZE_WHEN_PATCHING
814
815 static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
816 Bytecode_field field_access(caller, bci);
817 // This can be static or non-static field access
818 Bytecodes::Code code = field_access.code();
819
820 // We must load class, initialize class and resolve the field
821 fieldDescriptor result; // initialize class if needed
822 constantPoolHandle constants(THREAD, caller->constants());
823 LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
824 return result.field_holder();
825 }
826
827
828 //
829 // This routine patches sites where a class wasn't loaded or
830 // initialized at the time the code was generated. It handles
831 // references to classes, fields and forcing of initialization. Most
832 // of the cases are straightforward and involving simply forcing
833 // resolution of a class, rewriting the instruction stream with the
834 // needed constant and replacing the call in this function with the
835 // patched code. The case for static field is more complicated since
836 // the thread which is in the process of initializing a class can
837 // access it's static fields but other threads can't so the code
838 // either has to deoptimize when this case is detected or execute a
839 // check that the current thread is the initializing thread. The
840 // current
841 //
842 // Patches basically look like this:
843 //
844 //
845 // patch_site: jmp patch stub ;; will be patched
846 // continue: ...
847 // ...
848 // ...
849 // ...
850 //
851 // They have a stub which looks like this:
852 //
853 // ;; patch body
854 // movl <const>, reg (for class constants)
855 // <or> movl [reg1 + <const>], reg (for field offsets)
856 // <or> movl reg, [reg1 + <const>] (for field offsets)
857 // <being_init offset> <bytes to copy> <bytes to skip>
858 // patch_stub: call Runtime1::patch_code (through a runtime stub)
859 // jmp patch_site
860 //
861 //
862 // A normal patch is done by rewriting the patch body, usually a move,
863 // and then copying it into place over top of the jmp instruction
864 // being careful to flush caches and doing it in an MP-safe way. The
865 // constants following the patch body are used to find various pieces
866 // of the patch relative to the call site for Runtime1::patch_code.
867 // The case for getstatic and putstatic is more complicated because
868 // getstatic and putstatic have special semantics when executing while
869 // the class is being initialized. getstatic/putstatic on a class
870 // which is being_initialized may be executed by the initializing
871 // thread but other threads have to block when they execute it. This
872 // is accomplished in compiled code by executing a test of the current
873 // thread against the initializing thread of the class. It's emitted
874 // as boilerplate in their stub which allows the patched code to be
875 // executed before it's copied back into the main body of the nmethod.
876 //
877 // being_init: get_thread(<tmp reg>
878 // cmpl [reg1 + <init_thread_offset>], <tmp reg>
879 // jne patch_stub
880 // movl [reg1 + <const>], reg (for field offsets) <or>
881 // movl reg, [reg1 + <const>] (for field offsets)
882 // jmp continue
883 // <being_init offset> <bytes to copy> <bytes to skip>
884 // patch_stub: jmp Runtim1::patch_code (through a runtime stub)
885 // jmp patch_site
886 //
887 // If the class is being initialized the patch body is rewritten and
888 // the patch site is rewritten to jump to being_init, instead of
889 // patch_stub. Whenever this code is executed it checks the current
890 // thread against the initializing thread so other threads will enter
891 // the runtime and end up blocked waiting the class to finish
892 // initializing inside the calls to resolve_field below. The
893 // initializing class will continue on it's way. Once the class is
894 // fully_initialized, the intializing_thread of the class becomes
895 // null, so the next thread to execute this code will fail the test,
896 // call into patch_code and complete the patching process by copying
897 // the patch body back into the main part of the nmethod and resume
898 // executing.
899
900 // NB:
901 //
902 // Patchable instruction sequences inherently exhibit race conditions,
903 // where thread A is patching an instruction at the same time thread B
904 // is executing it. The algorithms we use ensure that any observation
905 // that B can make on any intermediate states during A's patching will
906 // always end up with a correct outcome. This is easiest if there are
907 // few or no intermediate states. (Some inline caches have two
908 // related instructions that must be patched in tandem. For those,
909 // intermediate states seem to be unavoidable, but we will get the
910 // right answer from all possible observation orders.)
911 //
912 // When patching the entry instruction at the head of a method, or a
913 // linkable call instruction inside of a method, we try very hard to
914 // use a patch sequence which executes as a single memory transaction.
915 // This means, in practice, that when thread A patches an instruction,
916 // it should patch a 32-bit or 64-bit word that somehow overlaps the
917 // instruction or is contained in it. We believe that memory hardware
918 // will never break up such a word write, if it is naturally aligned
919 // for the word being written. We also know that some CPUs work very
920 // hard to create atomic updates even of naturally unaligned words,
921 // but we don't want to bet the farm on this always working.
922 //
923 // Therefore, if there is any chance of a race condition, we try to
924 // patch only naturally aligned words, as single, full-word writes.
925
926 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* current, Runtime1::StubID stub_id ))
927 #ifndef PRODUCT
928 if (PrintC1Statistics) {
929 _patch_code_slowcase_cnt++;
930 }
931 #endif
932
933 ResourceMark rm(current);
934 RegisterMap reg_map(current,
935 RegisterMap::UpdateMap::skip,
936 RegisterMap::ProcessFrames::include,
937 RegisterMap::WalkContinuation::skip);
938 frame runtime_frame = current->last_frame();
939 frame caller_frame = runtime_frame.sender(®_map);
940
941 // last java frame on stack
942 vframeStream vfst(current, true);
943 assert(!vfst.at_end(), "Java frame must exist");
944
945 methodHandle caller_method(current, vfst.method());
946 // Note that caller_method->code() may not be same as caller_code because of OSR's
947 // Note also that in the presence of inlining it is not guaranteed
948 // that caller_method() == caller_code->method()
949
950 int bci = vfst.bci();
951 Bytecodes::Code code = caller_method()->java_code_at(bci);
952
953 // this is used by assertions in the access_field_patching_id
954 BasicType patch_field_type = T_ILLEGAL;
955 bool deoptimize_for_volatile = false;
956 bool deoptimize_for_atomic = false;
957 int patch_field_offset = -1;
958 Klass* init_klass = nullptr; // klass needed by load_klass_patching code
959 Klass* load_klass = nullptr; // klass needed by load_klass_patching code
960 Handle mirror(current, nullptr); // oop needed by load_mirror_patching code
961 Handle appendix(current, nullptr); // oop needed by appendix_patching code
962 bool load_klass_or_mirror_patch_id =
963 (stub_id == Runtime1::load_klass_patching_id || stub_id == Runtime1::load_mirror_patching_id);
964
965 if (stub_id == Runtime1::access_field_patching_id) {
966
967 Bytecode_field field_access(caller_method, bci);
968 fieldDescriptor result; // initialize class if needed
969 Bytecodes::Code code = field_access.code();
970 constantPoolHandle constants(current, caller_method->constants());
971 LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
972 patch_field_offset = result.offset();
973
974 // If we're patching a field which is volatile then at compile it
975 // must not have been know to be volatile, so the generated code
976 // isn't correct for a volatile reference. The nmethod has to be
977 // deoptimized so that the code can be regenerated correctly.
978 // This check is only needed for access_field_patching since this
979 // is the path for patching field offsets. load_klass is only
980 // used for patching references to oops which don't need special
981 // handling in the volatile case.
982
983 deoptimize_for_volatile = result.access_flags().is_volatile();
984
985 // If we are patching a field which should be atomic, then
986 // the generated code is not correct either, force deoptimizing.
987 // We need to only cover T_LONG and T_DOUBLE fields, as we can
988 // break access atomicity only for them.
989
990 // Strictly speaking, the deoptimization on 64-bit platforms
991 // is unnecessary, and T_LONG stores on 32-bit platforms need
992 // to be handled by special patching code when AlwaysAtomicAccesses
993 // becomes product feature. At this point, we are still going
994 // for the deoptimization for consistency against volatile
995 // accesses.
996
997 patch_field_type = result.field_type();
998 deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
999
1000 } else if (load_klass_or_mirror_patch_id) {
1001 Klass* k = nullptr;
1002 switch (code) {
1003 case Bytecodes::_putstatic:
1004 case Bytecodes::_getstatic:
1005 { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
1006 init_klass = klass;
1007 mirror = Handle(current, klass->java_mirror());
1008 }
1009 break;
1010 case Bytecodes::_new:
1011 { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
1012 k = caller_method->constants()->klass_at(bnew.index(), CHECK);
1013 }
1014 break;
1015 case Bytecodes::_multianewarray:
1016 { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
1017 k = caller_method->constants()->klass_at(mna.index(), CHECK);
1018 }
1019 break;
1020 case Bytecodes::_instanceof:
1021 { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
1022 k = caller_method->constants()->klass_at(io.index(), CHECK);
1023 }
1024 break;
1025 case Bytecodes::_checkcast:
1026 { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
1027 k = caller_method->constants()->klass_at(cc.index(), CHECK);
1028 }
1029 break;
1030 case Bytecodes::_anewarray:
1031 { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
1032 Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
1033 k = ek->array_klass(CHECK);
1034 }
1035 break;
1036 case Bytecodes::_ldc:
1037 case Bytecodes::_ldc_w:
1038 case Bytecodes::_ldc2_w:
1039 {
1040 Bytecode_loadconstant cc(caller_method, bci);
1041 oop m = cc.resolve_constant(CHECK);
1042 mirror = Handle(current, m);
1043 }
1044 break;
1045 default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
1046 }
1047 load_klass = k;
1048 } else if (stub_id == load_appendix_patching_id) {
1049 Bytecode_invoke bytecode(caller_method, bci);
1050 Bytecodes::Code bc = bytecode.invoke_code();
1051
1052 CallInfo info;
1053 constantPoolHandle pool(current, caller_method->constants());
1054 int index = bytecode.index();
1055 LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
1056 switch (bc) {
1057 case Bytecodes::_invokehandle: {
1058 ResolvedMethodEntry* entry = pool->cache()->set_method_handle(index, info);
1059 appendix = Handle(current, pool->cache()->appendix_if_resolved(entry));
1060 break;
1061 }
1062 case Bytecodes::_invokedynamic: {
1063 int indy_index = pool->decode_invokedynamic_index(index);
1064 appendix = Handle(current, pool->cache()->set_dynamic_call(info, indy_index));
1065 break;
1066 }
1067 default: fatal("unexpected bytecode for load_appendix_patching_id");
1068 }
1069 } else {
1070 ShouldNotReachHere();
1071 }
1072
1073 if (deoptimize_for_volatile || deoptimize_for_atomic) {
1074 // At compile time we assumed the field wasn't volatile/atomic but after
1075 // loading it turns out it was volatile/atomic so we have to throw the
1076 // compiled code out and let it be regenerated.
1077 if (TracePatching) {
1078 if (deoptimize_for_volatile) {
1079 tty->print_cr("Deoptimizing for patching volatile field reference");
1080 }
1081 if (deoptimize_for_atomic) {
1082 tty->print_cr("Deoptimizing for patching atomic field reference");
1083 }
1084 }
1085
1086 // It's possible the nmethod was invalidated in the last
1087 // safepoint, but if it's still alive then make it not_entrant.
1088 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1089 if (nm != nullptr) {
1090 nm->make_not_entrant();
1091 }
1092
1093 Deoptimization::deoptimize_frame(current, caller_frame.id());
1094
1095 // Return to the now deoptimized frame.
1096 }
1097
1098 // Now copy code back
1099
1100 {
1101 MutexLocker ml_patch (current, Patching_lock, Mutex::_no_safepoint_check_flag);
1102 //
1103 // Deoptimization may have happened while we waited for the lock.
1104 // In that case we don't bother to do any patching we just return
1105 // and let the deopt happen
1106 if (!caller_is_deopted(current)) {
1107 NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
1108 address instr_pc = jump->jump_destination();
1109 NativeInstruction* ni = nativeInstruction_at(instr_pc);
1110 if (ni->is_jump() ) {
1111 // the jump has not been patched yet
1112 // The jump destination is slow case and therefore not part of the stubs
1113 // (stubs are only for StaticCalls)
1114
1115 // format of buffer
1116 // ....
1117 // instr byte 0 <-- copy_buff
1118 // instr byte 1
1119 // ..
1120 // instr byte n-1
1121 // n
1122 // .... <-- call destination
1123
1124 address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
1125 unsigned char* byte_count = (unsigned char*) (stub_location - 1);
1126 unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
1127 unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
1128 address copy_buff = stub_location - *byte_skip - *byte_count;
1129 address being_initialized_entry = stub_location - *being_initialized_entry_offset;
1130 if (TracePatching) {
1131 ttyLocker ttyl;
1132 tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT " (%s)", Bytecodes::name(code), bci,
1133 p2i(instr_pc), (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
1134 nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
1135 assert(caller_code != nullptr, "nmethod not found");
1136
1137 // NOTE we use pc() not original_pc() because we already know they are
1138 // identical otherwise we'd have never entered this block of code
1139
1140 const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
1141 assert(map != nullptr, "null check");
1142 map->print();
1143 tty->cr();
1144
1145 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1146 }
1147 // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
1148 bool do_patch = true;
1149 if (stub_id == Runtime1::access_field_patching_id) {
1150 // The offset may not be correct if the class was not loaded at code generation time.
1151 // Set it now.
1152 NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
1153 assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1154 assert(patch_field_offset >= 0, "illegal offset");
1155 n_move->add_offset_in_bytes(patch_field_offset);
1156 } else if (load_klass_or_mirror_patch_id) {
1157 // If a getstatic or putstatic is referencing a klass which
1158 // isn't fully initialized, the patch body isn't copied into
1159 // place until initialization is complete. In this case the
1160 // patch site is setup so that any threads besides the
1161 // initializing thread are forced to come into the VM and
1162 // block.
1163 do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1164 InstanceKlass::cast(init_klass)->is_initialized();
1165 NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1166 if (jump->jump_destination() == being_initialized_entry) {
1167 assert(do_patch == true, "initialization must be complete at this point");
1168 } else {
1169 // patch the instruction <move reg, klass>
1170 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1171
1172 assert(n_copy->data() == 0 ||
1173 n_copy->data() == (intptr_t)Universe::non_oop_word(),
1174 "illegal init value");
1175 if (stub_id == Runtime1::load_klass_patching_id) {
1176 assert(load_klass != nullptr, "klass not set");
1177 n_copy->set_data((intx) (load_klass));
1178 } else {
1179 // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1180 n_copy->set_data(cast_from_oop<intx>(mirror()));
1181 }
1182
1183 if (TracePatching) {
1184 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1185 }
1186 }
1187 } else if (stub_id == Runtime1::load_appendix_patching_id) {
1188 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1189 assert(n_copy->data() == 0 ||
1190 n_copy->data() == (intptr_t)Universe::non_oop_word(),
1191 "illegal init value");
1192 n_copy->set_data(cast_from_oop<intx>(appendix()));
1193
1194 if (TracePatching) {
1195 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1196 }
1197 } else {
1198 ShouldNotReachHere();
1199 }
1200
1201 if (do_patch) {
1202 // replace instructions
1203 // first replace the tail, then the call
1204 #ifdef ARM
1205 if((load_klass_or_mirror_patch_id ||
1206 stub_id == Runtime1::load_appendix_patching_id) &&
1207 nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1208 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1209 address addr = nullptr;
1210 assert(nm != nullptr, "invalid nmethod_pc");
1211 RelocIterator mds(nm, copy_buff, copy_buff + 1);
1212 while (mds.next()) {
1213 if (mds.type() == relocInfo::oop_type) {
1214 assert(stub_id == Runtime1::load_mirror_patching_id ||
1215 stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1216 oop_Relocation* r = mds.oop_reloc();
1217 addr = (address)r->oop_addr();
1218 break;
1219 } else if (mds.type() == relocInfo::metadata_type) {
1220 assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1221 metadata_Relocation* r = mds.metadata_reloc();
1222 addr = (address)r->metadata_addr();
1223 break;
1224 }
1225 }
1226 assert(addr != nullptr, "metadata relocation must exist");
1227 copy_buff -= *byte_count;
1228 NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1229 n_copy2->set_pc_relative_offset(addr, instr_pc);
1230 }
1231 #endif
1232
1233 for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
1234 address ptr = copy_buff + i;
1235 int a_byte = (*ptr) & 0xFF;
1236 address dst = instr_pc + i;
1237 *(unsigned char*)dst = (unsigned char) a_byte;
1238 }
1239 ICache::invalidate_range(instr_pc, *byte_count);
1240 NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1241
1242 if (load_klass_or_mirror_patch_id ||
1243 stub_id == Runtime1::load_appendix_patching_id) {
1244 relocInfo::relocType rtype =
1245 (stub_id == Runtime1::load_klass_patching_id) ?
1246 relocInfo::metadata_type :
1247 relocInfo::oop_type;
1248 // update relocInfo to metadata
1249 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1250 assert(nm != nullptr, "invalid nmethod_pc");
1251
1252 // The old patch site is now a move instruction so update
1253 // the reloc info so that it will get updated during
1254 // future GCs.
1255 RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1256 relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1257 relocInfo::none, rtype);
1258 }
1259
1260 } else {
1261 ICache::invalidate_range(copy_buff, *byte_count);
1262 NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1263 }
1264 }
1265 }
1266 }
1267
1268 // If we are patching in a non-perm oop, make sure the nmethod
1269 // is on the right list.
1270 {
1271 MutexLocker ml_code (current, CodeCache_lock, Mutex::_no_safepoint_check_flag);
1272 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1273 guarantee(nm != nullptr, "only nmethods can contain non-perm oops");
1274
1275 // Since we've patched some oops in the nmethod,
1276 // (re)register it with the heap.
1277 Universe::heap()->register_nmethod(nm);
1278 }
1279 JRT_END
1280
1281 #else // DEOPTIMIZE_WHEN_PATCHING
1282
1283 static bool is_patching_needed(JavaThread* current, Runtime1::StubID stub_id) {
1284 if (stub_id == Runtime1::load_klass_patching_id ||
1285 stub_id == Runtime1::load_mirror_patching_id) {
1286 // last java frame on stack
1287 vframeStream vfst(current, true);
1288 assert(!vfst.at_end(), "Java frame must exist");
1289
1290 methodHandle caller_method(current, vfst.method());
1291 int bci = vfst.bci();
1292 Bytecodes::Code code = caller_method()->java_code_at(bci);
1293
1294 switch (code) {
1295 case Bytecodes::_new:
1296 case Bytecodes::_anewarray:
1297 case Bytecodes::_multianewarray:
1298 case Bytecodes::_instanceof:
1299 case Bytecodes::_checkcast: {
1300 Bytecode bc(caller_method(), caller_method->bcp_from(bci));
1301 constantTag tag = caller_method->constants()->tag_at(bc.get_index_u2(code));
1302 if (tag.is_unresolved_klass_in_error()) {
1303 return false; // throws resolution error
1304 }
1305 break;
1306 }
1307
1308 default: break;
1309 }
1310 }
1311 return true;
1312 }
1313
1314 void Runtime1::patch_code(JavaThread* current, Runtime1::StubID stub_id) {
1315 #ifndef PRODUCT
1316 if (PrintC1Statistics) {
1317 _patch_code_slowcase_cnt++;
1318 }
1319 #endif
1320
1321 // Enable WXWrite: the function is called by c1 stub as a runtime function
1322 // (see another implementation above).
1323 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
1324
1325 if (TracePatching) {
1326 tty->print_cr("Deoptimizing because patch is needed");
1327 }
1328
1329 RegisterMap reg_map(current,
1330 RegisterMap::UpdateMap::skip,
1331 RegisterMap::ProcessFrames::include,
1332 RegisterMap::WalkContinuation::skip);
1333
1334 frame runtime_frame = current->last_frame();
1335 frame caller_frame = runtime_frame.sender(®_map);
1336 assert(caller_frame.is_compiled_frame(), "Wrong frame type");
1337
1338 if (is_patching_needed(current, stub_id)) {
1339 // Make sure the nmethod is invalidated, i.e. made not entrant.
1340 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1341 if (nm != nullptr) {
1342 nm->make_not_entrant();
1343 }
1344 }
1345
1346 Deoptimization::deoptimize_frame(current, caller_frame.id());
1347 // Return to the now deoptimized frame.
1348 postcond(caller_is_deopted(current));
1349 }
1350
1351 #endif // DEOPTIMIZE_WHEN_PATCHING
1352
1353 // Entry point for compiled code. We want to patch a nmethod.
1354 // We don't do a normal VM transition here because we want to
1355 // know after the patching is complete and any safepoint(s) are taken
1356 // if the calling nmethod was deoptimized. We do this by calling a
1357 // helper method which does the normal VM transition and when it
1358 // completes we can check for deoptimization. This simplifies the
1359 // assembly code in the cpu directories.
1360 //
1361 int Runtime1::move_klass_patching(JavaThread* current) {
1362 //
1363 // NOTE: we are still in Java
1364 //
1365 debug_only(NoHandleMark nhm;)
1366 {
1367 // Enter VM mode
1368 ResetNoHandleMark rnhm;
1369 patch_code(current, load_klass_patching_id);
1370 }
1371 // Back in JAVA, use no oops DON'T safepoint
1372
1373 // Return true if calling code is deoptimized
1374
1375 return caller_is_deopted(current);
1376 }
1377
1378 int Runtime1::move_mirror_patching(JavaThread* current) {
1379 //
1380 // NOTE: we are still in Java
1381 //
1382 debug_only(NoHandleMark nhm;)
1383 {
1384 // Enter VM mode
1385 ResetNoHandleMark rnhm;
1386 patch_code(current, load_mirror_patching_id);
1387 }
1388 // Back in JAVA, use no oops DON'T safepoint
1389
1390 // Return true if calling code is deoptimized
1391
1392 return caller_is_deopted(current);
1393 }
1394
1395 int Runtime1::move_appendix_patching(JavaThread* current) {
1396 //
1397 // NOTE: we are still in Java
1398 //
1399 debug_only(NoHandleMark nhm;)
1400 {
1401 // Enter VM mode
1402 ResetNoHandleMark rnhm;
1403 patch_code(current, load_appendix_patching_id);
1404 }
1405 // Back in JAVA, use no oops DON'T safepoint
1406
1407 // Return true if calling code is deoptimized
1408
1409 return caller_is_deopted(current);
1410 }
1411
1412 // Entry point for compiled code. We want to patch a nmethod.
1413 // We don't do a normal VM transition here because we want to
1414 // know after the patching is complete and any safepoint(s) are taken
1415 // if the calling nmethod was deoptimized. We do this by calling a
1416 // helper method which does the normal VM transition and when it
1417 // completes we can check for deoptimization. This simplifies the
1418 // assembly code in the cpu directories.
1419 //
1420 int Runtime1::access_field_patching(JavaThread* current) {
1421 //
1422 // NOTE: we are still in Java
1423 //
1424 // Handles created in this function will be deleted by the
1425 // HandleMarkCleaner in the transition to the VM.
1426 NoHandleMark nhm;
1427 {
1428 // Enter VM mode
1429 ResetNoHandleMark rnhm;
1430 patch_code(current, access_field_patching_id);
1431 }
1432 // Back in JAVA, use no oops DON'T safepoint
1433
1434 // Return true if calling code is deoptimized
1435
1436 return caller_is_deopted(current);
1437 }
1438
1439
1440 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1441 // for now we just print out the block id
1442 tty->print("%d ", block_id);
1443 JRT_END
1444
1445
1446 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1447 // had to return int instead of bool, otherwise there may be a mismatch
1448 // between the C calling convention and the Java one.
1449 // e.g., on x86, GCC may clear only %al when returning a bool false, but
1450 // JVM takes the whole %eax as the return value, which may misinterpret
1451 // the return value as a boolean true.
1452
1453 assert(mirror != nullptr, "should null-check on mirror before calling");
1454 Klass* k = java_lang_Class::as_Klass(mirror);
1455 return (k != nullptr && obj != nullptr && obj->is_a(k)) ? 1 : 0;
1456 JRT_END
1457
1458 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* current))
1459 ResourceMark rm;
1460
1461 RegisterMap reg_map(current,
1462 RegisterMap::UpdateMap::skip,
1463 RegisterMap::ProcessFrames::include,
1464 RegisterMap::WalkContinuation::skip);
1465 frame runtime_frame = current->last_frame();
1466 frame caller_frame = runtime_frame.sender(®_map);
1467
1468 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1469 assert (nm != nullptr, "no more nmethod?");
1470 nm->make_not_entrant();
1471
1472 methodHandle m(current, nm->method());
1473 MethodData* mdo = m->method_data();
1474
1475 if (mdo == nullptr && !HAS_PENDING_EXCEPTION) {
1476 // Build an MDO. Ignore errors like OutOfMemory;
1477 // that simply means we won't have an MDO to update.
1478 Method::build_profiling_method_data(m, THREAD);
1479 if (HAS_PENDING_EXCEPTION) {
1480 // Only metaspace OOM is expected. No Java code executed.
1481 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1482 CLEAR_PENDING_EXCEPTION;
1483 }
1484 mdo = m->method_data();
1485 }
1486
1487 if (mdo != nullptr) {
1488 mdo->inc_trap_count(Deoptimization::Reason_none);
1489 }
1490
1491 if (TracePredicateFailedTraps) {
1492 stringStream ss1, ss2;
1493 vframeStream vfst(current);
1494 Method* inlinee = vfst.method();
1495 inlinee->print_short_name(&ss1);
1496 m->print_short_name(&ss2);
1497 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()));
1498 }
1499
1500
1501 Deoptimization::deoptimize_frame(current, caller_frame.id());
1502
1503 JRT_END
1504
1505 // Check exception if AbortVMOnException flag set
1506 JRT_LEAF(void, Runtime1::check_abort_on_vm_exception(oopDesc* ex))
1507 ResourceMark rm;
1508 const char* message = nullptr;
1509 if (ex->is_a(vmClasses::Throwable_klass())) {
1510 oop msg = java_lang_Throwable::message(ex);
1511 if (msg != nullptr) {
1512 message = java_lang_String::as_utf8_string(msg);
1513 }
1514 }
1515 Exceptions::debug_check_abort(ex->klass()->external_name(), message);
1516 JRT_END
1517
1518 #ifndef PRODUCT
1519 void Runtime1::print_statistics() {
1520 tty->print_cr("C1 Runtime statistics:");
1521 tty->print_cr(" _resolve_invoke_virtual_cnt: %u", SharedRuntime::_resolve_virtual_ctr);
1522 tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %u", SharedRuntime::_resolve_opt_virtual_ctr);
1523 tty->print_cr(" _resolve_invoke_static_cnt: %u", SharedRuntime::_resolve_static_ctr);
1524 tty->print_cr(" _handle_wrong_method_cnt: %u", SharedRuntime::_wrong_method_ctr);
1525 tty->print_cr(" _ic_miss_cnt: %u", SharedRuntime::_ic_miss_ctr);
1526 tty->print_cr(" _generic_arraycopystub_cnt: %u", _generic_arraycopystub_cnt);
1527 tty->print_cr(" _byte_arraycopy_cnt: %u", _byte_arraycopy_stub_cnt);
1528 tty->print_cr(" _short_arraycopy_cnt: %u", _short_arraycopy_stub_cnt);
1529 tty->print_cr(" _int_arraycopy_cnt: %u", _int_arraycopy_stub_cnt);
1530 tty->print_cr(" _long_arraycopy_cnt: %u", _long_arraycopy_stub_cnt);
1531 tty->print_cr(" _oop_arraycopy_cnt: %u", _oop_arraycopy_stub_cnt);
1532 tty->print_cr(" _arraycopy_slowcase_cnt: %u", _arraycopy_slowcase_cnt);
1533 tty->print_cr(" _arraycopy_checkcast_cnt: %u", _arraycopy_checkcast_cnt);
1534 tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%u", _arraycopy_checkcast_attempt_cnt);
1535
1536 tty->print_cr(" _new_type_array_slowcase_cnt: %u", _new_type_array_slowcase_cnt);
1537 tty->print_cr(" _new_object_array_slowcase_cnt: %u", _new_object_array_slowcase_cnt);
1538 tty->print_cr(" _new_instance_slowcase_cnt: %u", _new_instance_slowcase_cnt);
1539 tty->print_cr(" _new_multi_array_slowcase_cnt: %u", _new_multi_array_slowcase_cnt);
1540 tty->print_cr(" _monitorenter_slowcase_cnt: %u", _monitorenter_slowcase_cnt);
1541 tty->print_cr(" _monitorexit_slowcase_cnt: %u", _monitorexit_slowcase_cnt);
1542 tty->print_cr(" _patch_code_slowcase_cnt: %u", _patch_code_slowcase_cnt);
1543
1544 tty->print_cr(" _throw_range_check_exception_count: %u:", _throw_range_check_exception_count);
1545 tty->print_cr(" _throw_index_exception_count: %u:", _throw_index_exception_count);
1546 tty->print_cr(" _throw_div0_exception_count: %u:", _throw_div0_exception_count);
1547 tty->print_cr(" _throw_null_pointer_exception_count: %u:", _throw_null_pointer_exception_count);
1548 tty->print_cr(" _throw_class_cast_exception_count: %u:", _throw_class_cast_exception_count);
1549 tty->print_cr(" _throw_incompatible_class_change_error_count: %u:", _throw_incompatible_class_change_error_count);
1550 tty->print_cr(" _throw_count: %u:", _throw_count);
1551
1552 SharedRuntime::print_ic_miss_histogram();
1553 tty->cr();
1554 }
1555 #endif // PRODUCT