1 /*
2 * Copyright (c) 1999, 2021, 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/biasedLocking.hpp"
63 #include "runtime/fieldDescriptor.inline.hpp"
64 #include "runtime/frame.inline.hpp"
65 #include "runtime/handles.inline.hpp"
66 #include "runtime/interfaceSupport.inline.hpp"
67 #include "runtime/javaCalls.hpp"
68 #include "runtime/sharedRuntime.hpp"
69 #include "runtime/stackWatermarkSet.hpp"
70 #include "runtime/stubRoutines.hpp"
71 #include "runtime/threadCritical.hpp"
72 #include "runtime/vframe.inline.hpp"
73 #include "runtime/vframeArray.hpp"
74 #include "runtime/vm_version.hpp"
75 #include "utilities/copy.hpp"
76 #include "utilities/events.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 int Runtime1::_generic_arraycopystub_cnt = 0;
121 int Runtime1::_arraycopy_slowcase_cnt = 0;
122 int Runtime1::_arraycopy_checkcast_cnt = 0;
123 int Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
124 int Runtime1::_new_type_array_slowcase_cnt = 0;
125 int Runtime1::_new_object_array_slowcase_cnt = 0;
126 int Runtime1::_new_instance_slowcase_cnt = 0;
127 int Runtime1::_new_multi_array_slowcase_cnt = 0;
128 int Runtime1::_monitorenter_slowcase_cnt = 0;
129 int Runtime1::_monitorexit_slowcase_cnt = 0;
130 int Runtime1::_patch_code_slowcase_cnt = 0;
131 int Runtime1::_throw_range_check_exception_count = 0;
132 int Runtime1::_throw_index_exception_count = 0;
133 int Runtime1::_throw_div0_exception_count = 0;
134 int Runtime1::_throw_null_pointer_exception_count = 0;
135 int Runtime1::_throw_class_cast_exception_count = 0;
136 int Runtime1::_throw_incompatible_class_change_error_count = 0;
137 int Runtime1::_throw_count = 0;
138
139 static int _byte_arraycopy_stub_cnt = 0;
140 static int _short_arraycopy_stub_cnt = 0;
141 static int _int_arraycopy_stub_cnt = 0;
142 static int _long_arraycopy_stub_cnt = 0;
143 static int _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 NULL;
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, false);
171 frame runtime_frame = current->last_frame();
172 frame caller_frame = runtime_frame.sender(®_map);
173 assert(caller_frame.is_compiled_frame(), "must be compiled");
174 return caller_frame.is_deoptimized_frame();
175 }
176
177 // Stress deoptimization
178 static void deopt_caller(JavaThread* current) {
179 if (!caller_is_deopted(current)) {
180 RegisterMap reg_map(current, false);
181 frame runtime_frame = current->last_frame();
182 frame caller_frame = runtime_frame.sender(®_map);
183 Deoptimization::deoptimize_frame(current, caller_frame.id());
184 assert(caller_is_deopted(current), "Must be deoptimized");
185 }
186 }
187
188 class StubIDStubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
189 private:
190 Runtime1::StubID _id;
191 public:
192 StubIDStubAssemblerCodeGenClosure(Runtime1::StubID id) : _id(id) {}
193 virtual OopMapSet* generate_code(StubAssembler* sasm) {
194 return Runtime1::generate_code_for(_id, sasm);
195 }
196 };
197
198 CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, int stub_id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
199 ResourceMark rm;
200 // create code buffer for code storage
201 CodeBuffer code(buffer_blob);
202
203 OopMapSet* oop_maps;
204 int frame_size;
205 bool must_gc_arguments;
206
207 Compilation::setup_code_buffer(&code, 0);
208
209 // create assembler for code generation
210 StubAssembler* sasm = new StubAssembler(&code, name, stub_id);
211 // generate code for runtime stub
212 oop_maps = cl->generate_code(sasm);
213 assert(oop_maps == NULL || sasm->frame_size() != no_frame_size,
214 "if stub has an oop map it must have a valid frame size");
215 assert(!expect_oop_map || oop_maps != NULL, "must have an oopmap");
216
217 // align so printing shows nop's instead of random code at the end (SimpleStubs are aligned)
218 sasm->align(BytesPerWord);
219 // make sure all code is in code buffer
220 sasm->flush();
221
222 frame_size = sasm->frame_size();
223 must_gc_arguments = sasm->must_gc_arguments();
224 // create blob - distinguish a few special cases
225 CodeBlob* blob = RuntimeStub::new_runtime_stub(name,
226 &code,
227 CodeOffsets::frame_never_safe,
228 frame_size,
229 oop_maps,
230 must_gc_arguments);
231 assert(blob != NULL, "blob must exist");
232 return blob;
233 }
234
235 void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
236 assert(0 <= id && id < number_of_ids, "illegal stub id");
237 bool expect_oop_map = true;
238 #ifdef ASSERT
239 // Make sure that stubs that need oopmaps have them
240 switch (id) {
241 // These stubs don't need to have an oopmap
242 case dtrace_object_alloc_id:
243 case slow_subtype_check_id:
244 case fpu2long_stub_id:
245 case unwind_exception_id:
246 case counter_overflow_id:
247 #if defined(PPC32)
248 case handle_exception_nofpu_id:
249 #endif
250 expect_oop_map = false;
251 break;
252 default:
253 break;
254 }
255 #endif
256 StubIDStubAssemblerCodeGenClosure cl(id);
257 CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
258 // install blob
259 _blobs[id] = blob;
260 }
261
262 void Runtime1::initialize(BufferBlob* blob) {
263 // platform-dependent initialization
264 initialize_pd();
265 // generate stubs
266 for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
267 // printing
268 #ifndef PRODUCT
269 if (PrintSimpleStubs) {
270 ResourceMark rm;
271 for (int id = 0; id < number_of_ids; id++) {
272 _blobs[id]->print();
273 if (_blobs[id]->oop_maps() != NULL) {
274 _blobs[id]->oop_maps()->print();
275 }
276 }
277 }
278 #endif
279 BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
280 bs->generate_c1_runtime_stubs(blob);
281 }
282
283 CodeBlob* Runtime1::blob_for(StubID id) {
284 assert(0 <= id && id < number_of_ids, "illegal stub id");
285 return _blobs[id];
286 }
287
288
289 const char* Runtime1::name_for(StubID id) {
290 assert(0 <= id && id < number_of_ids, "illegal stub id");
291 return _blob_names[id];
292 }
293
294 const char* Runtime1::name_for_address(address entry) {
295 for (int id = 0; id < number_of_ids; id++) {
296 if (entry == entry_for((StubID)id)) return name_for((StubID)id);
297 }
298
299 #define FUNCTION_CASE(a, f) \
300 if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f)) return #f
301
302 FUNCTION_CASE(entry, os::javaTimeMillis);
303 FUNCTION_CASE(entry, os::javaTimeNanos);
304 FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
305 FUNCTION_CASE(entry, SharedRuntime::d2f);
306 FUNCTION_CASE(entry, SharedRuntime::d2i);
307 FUNCTION_CASE(entry, SharedRuntime::d2l);
308 FUNCTION_CASE(entry, SharedRuntime::dcos);
309 FUNCTION_CASE(entry, SharedRuntime::dexp);
310 FUNCTION_CASE(entry, SharedRuntime::dlog);
311 FUNCTION_CASE(entry, SharedRuntime::dlog10);
312 FUNCTION_CASE(entry, SharedRuntime::dpow);
313 FUNCTION_CASE(entry, SharedRuntime::drem);
314 FUNCTION_CASE(entry, SharedRuntime::dsin);
315 FUNCTION_CASE(entry, SharedRuntime::dtan);
316 FUNCTION_CASE(entry, SharedRuntime::f2i);
317 FUNCTION_CASE(entry, SharedRuntime::f2l);
318 FUNCTION_CASE(entry, SharedRuntime::frem);
319 FUNCTION_CASE(entry, SharedRuntime::l2d);
320 FUNCTION_CASE(entry, SharedRuntime::l2f);
321 FUNCTION_CASE(entry, SharedRuntime::ldiv);
322 FUNCTION_CASE(entry, SharedRuntime::lmul);
323 FUNCTION_CASE(entry, SharedRuntime::lrem);
324 FUNCTION_CASE(entry, SharedRuntime::lrem);
325 FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
326 FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
327 FUNCTION_CASE(entry, is_instance_of);
328 FUNCTION_CASE(entry, trace_block_entry);
329 #ifdef JFR_HAVE_INTRINSICS
330 FUNCTION_CASE(entry, JFR_TIME_FUNCTION);
331 #endif
332 FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
333 FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
334 FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
335 FUNCTION_CASE(entry, StubRoutines::dexp());
336 FUNCTION_CASE(entry, StubRoutines::dlog());
337 FUNCTION_CASE(entry, StubRoutines::dlog10());
338 FUNCTION_CASE(entry, StubRoutines::dpow());
339 FUNCTION_CASE(entry, StubRoutines::dsin());
340 FUNCTION_CASE(entry, StubRoutines::dcos());
341 FUNCTION_CASE(entry, StubRoutines::dtan());
342
343 #undef FUNCTION_CASE
344
345 // Soft float adds more runtime names.
346 return pd_name_for_address(entry);
347 }
348
349
350 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* current, Klass* klass))
351 NOT_PRODUCT(_new_instance_slowcase_cnt++;)
352
353 assert(klass->is_klass(), "not a class");
354 Handle holder(current, klass->klass_holder()); // keep the klass alive
355 InstanceKlass* h = InstanceKlass::cast(klass);
356 h->check_valid_for_instantiation(true, CHECK);
357 // make sure klass is initialized
358 h->initialize(CHECK);
359 // allocate instance and return via TLS
360 oop obj = h->allocate_instance(CHECK);
361 current->set_vm_result(obj);
362 JRT_END
363
364
365 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* current, Klass* klass, jint length))
366 NOT_PRODUCT(_new_type_array_slowcase_cnt++;)
367 // Note: no handle for klass needed since they are not used
368 // anymore after new_typeArray() and no GC can happen before.
369 // (This may have to change if this code changes!)
370 assert(klass->is_klass(), "not a class");
371 BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
372 oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
373 current->set_vm_result(obj);
374 // This is pretty rare but this runtime patch is stressful to deoptimization
375 // if we deoptimize here so force a deopt to stress the path.
376 if (DeoptimizeALot) {
377 deopt_caller(current);
378 }
379
380 JRT_END
381
382
383 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* current, Klass* array_klass, jint length))
384 NOT_PRODUCT(_new_object_array_slowcase_cnt++;)
385
386 // Note: no handle for klass needed since they are not used
387 // anymore after new_objArray() and no GC can happen before.
388 // (This may have to change if this code changes!)
389 assert(array_klass->is_klass(), "not a class");
390 Handle holder(current, array_klass->klass_holder()); // keep the klass alive
391 Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
392 objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
393 current->set_vm_result(obj);
394 // This is pretty rare but this runtime patch is stressful to deoptimization
395 // if we deoptimize here so force a deopt to stress the path.
396 if (DeoptimizeALot) {
397 deopt_caller(current);
398 }
399 JRT_END
400
401
402 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* current, Klass* klass, int rank, jint* dims))
403 NOT_PRODUCT(_new_multi_array_slowcase_cnt++;)
404
405 assert(klass->is_klass(), "not a class");
406 assert(rank >= 1, "rank must be nonzero");
407 Handle holder(current, klass->klass_holder()); // keep the klass alive
408 oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
409 current->set_vm_result(obj);
410 JRT_END
411
412
413 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* current, StubID id))
414 tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
415 JRT_END
416
417
418 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* current, oopDesc* obj))
419 ResourceMark rm(current);
420 const char* klass_name = obj->klass()->external_name();
421 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayStoreException(), klass_name);
422 JRT_END
423
424
425 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
426 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
427 // method) method is passed as an argument. In order to do that it is embedded in the code as
428 // a constant.
429 static nmethod* counter_overflow_helper(JavaThread* current, int branch_bci, Method* m) {
430 nmethod* osr_nm = NULL;
431 methodHandle method(current, m);
432
433 RegisterMap map(current, false);
434 frame fr = current->last_frame().sender(&map);
435 nmethod* nm = (nmethod*) fr.cb();
436 assert(nm!= NULL && nm->is_nmethod(), "Sanity check");
437 methodHandle enclosing_method(current, nm->method());
438
439 CompLevel level = (CompLevel)nm->comp_level();
440 int bci = InvocationEntryBci;
441 if (branch_bci != InvocationEntryBci) {
442 // Compute destination bci
443 address pc = method()->code_base() + branch_bci;
444 Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
445 int offset = 0;
446 switch (branch) {
447 case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
448 case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
449 case Bytecodes::_if_icmple: case Bytecodes::_ifle:
450 case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
451 case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
452 case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
453 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
454 offset = (int16_t)Bytes::get_Java_u2(pc + 1);
455 break;
456 case Bytecodes::_goto_w:
457 offset = Bytes::get_Java_u4(pc + 1);
458 break;
459 default: ;
460 }
461 bci = branch_bci + offset;
462 }
463 osr_nm = CompilationPolicy::event(enclosing_method, method, branch_bci, bci, level, nm, current);
464 return osr_nm;
465 }
466
467 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* current, int bci, Method* method))
468 nmethod* osr_nm;
469 JRT_BLOCK
470 osr_nm = counter_overflow_helper(current, bci, method);
471 if (osr_nm != NULL) {
472 RegisterMap map(current, false);
473 frame fr = current->last_frame().sender(&map);
474 Deoptimization::deoptimize_frame(current, fr.id());
475 }
476 JRT_BLOCK_END
477 return NULL;
478 JRT_END
479
480 extern void vm_exit(int code);
481
482 // Enter this method from compiled code handler below. This is where we transition
483 // to VM mode. This is done as a helper routine so that the method called directly
484 // from compiled code does not have to transition to VM. This allows the entry
485 // method to see if the nmethod that we have just looked up a handler for has
486 // been deoptimized while we were in the vm. This simplifies the assembly code
487 // cpu directories.
488 //
489 // We are entering here from exception stub (via the entry method below)
490 // If there is a compiled exception handler in this method, we will continue there;
491 // otherwise we will unwind the stack and continue at the caller of top frame method
492 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
493 // control the area where we can allow a safepoint. After we exit the safepoint area we can
494 // check to see if the handler we are going to return is now in a nmethod that has
495 // been deoptimized. If that is the case we return the deopt blob
496 // unpack_with_exception entry instead. This makes life for the exception blob easier
497 // because making that same check and diverting is painful from assembly language.
498 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* current, oopDesc* ex, address pc, nmethod*& nm))
499 // Reset method handle flag.
500 current->set_is_method_handle_return(false);
501
502 Handle exception(current, ex);
503
504 // This function is called when we are about to throw an exception. Therefore,
505 // we have to poll the stack watermark barrier to make sure that not yet safe
506 // stack frames are made safe before returning into them.
507 if (current->last_frame().cb() == Runtime1::blob_for(Runtime1::handle_exception_from_callee_id)) {
508 // The Runtime1::handle_exception_from_callee_id handler is invoked after the
509 // frame has been unwound. It instead builds its own stub frame, to call the
510 // runtime. But the throwing frame has already been unwound here.
511 StackWatermarkSet::after_unwind(current);
512 }
513
514 nm = CodeCache::find_nmethod(pc);
515 assert(nm != NULL, "this is not an nmethod");
516 // Adjust the pc as needed/
517 if (nm->is_deopt_pc(pc)) {
518 RegisterMap map(current, false);
519 frame exception_frame = current->last_frame().sender(&map);
520 // if the frame isn't deopted then pc must not correspond to the caller of last_frame
521 assert(exception_frame.is_deoptimized_frame(), "must be deopted");
522 pc = exception_frame.pc();
523 }
524 assert(exception.not_null(), "NULL exceptions should be handled by throw_exception");
525 // Check that exception is a subclass of Throwable
526 assert(exception->is_a(vmClasses::Throwable_klass()),
527 "Exception not subclass of Throwable");
528
529 // debugging support
530 // tracing
531 if (log_is_enabled(Info, exceptions)) {
532 ResourceMark rm;
533 stringStream tempst;
534 assert(nm->method() != NULL, "Unexpected NULL method()");
535 tempst.print("C1 compiled method <%s>\n"
536 " at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
537 nm->method()->print_value_string(), p2i(pc), p2i(current));
538 Exceptions::log_exception(exception, tempst.as_string());
539 }
540 // for AbortVMOnException flag
541 Exceptions::debug_check_abort(exception);
542
543 // Check the stack guard pages and reenable them if necessary and there is
544 // enough space on the stack to do so. Use fast exceptions only if the guard
545 // pages are enabled.
546 bool guard_pages_enabled = current->stack_overflow_state()->reguard_stack_if_needed();
547
548 if (JvmtiExport::can_post_on_exceptions()) {
549 // To ensure correct notification of exception catches and throws
550 // we have to deoptimize here. If we attempted to notify the
551 // catches and throws during this exception lookup it's possible
552 // we could deoptimize on the way out of the VM and end back in
553 // the interpreter at the throw site. This would result in double
554 // notifications since the interpreter would also notify about
555 // these same catches and throws as it unwound the frame.
556
557 RegisterMap reg_map(current);
558 frame stub_frame = current->last_frame();
559 frame caller_frame = stub_frame.sender(®_map);
560
561 // We don't really want to deoptimize the nmethod itself since we
562 // can actually continue in the exception handler ourselves but I
563 // don't see an easy way to have the desired effect.
564 Deoptimization::deoptimize_frame(current, caller_frame.id());
565 assert(caller_is_deopted(current), "Must be deoptimized");
566
567 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
568 }
569
570 // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
571 if (guard_pages_enabled) {
572 address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
573 if (fast_continuation != NULL) {
574 // Set flag if return address is a method handle call site.
575 current->set_is_method_handle_return(nm->is_method_handle_return(pc));
576 return fast_continuation;
577 }
578 }
579
580 // If the stack guard pages are enabled, check whether there is a handler in
581 // the current method. Otherwise (guard pages disabled), force an unwind and
582 // skip the exception cache update (i.e., just leave continuation==NULL).
583 address continuation = NULL;
584 if (guard_pages_enabled) {
585
586 // New exception handling mechanism can support inlined methods
587 // with exception handlers since the mappings are from PC to PC
588
589 // Clear out the exception oop and pc since looking up an
590 // exception handler can cause class loading, which might throw an
591 // exception and those fields are expected to be clear during
592 // normal bytecode execution.
593 current->clear_exception_oop_and_pc();
594
595 bool recursive_exception = false;
596 continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
597 // If an exception was thrown during exception dispatch, the exception oop may have changed
598 current->set_exception_oop(exception());
599 current->set_exception_pc(pc);
600
601 // the exception cache is used only by non-implicit exceptions
602 // Update the exception cache only when there didn't happen
603 // another exception during the computation of the compiled
604 // exception handler. Checking for exception oop equality is not
605 // sufficient because some exceptions are pre-allocated and reused.
606 if (continuation != NULL && !recursive_exception) {
607 nm->add_handler_for_exception_and_pc(exception, pc, continuation);
608 }
609 }
610
611 current->set_vm_result(exception());
612 // Set flag if return address is a method handle call site.
613 current->set_is_method_handle_return(nm->is_method_handle_return(pc));
614
615 if (log_is_enabled(Info, exceptions)) {
616 ResourceMark rm;
617 log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
618 " for exception thrown at PC " PTR_FORMAT,
619 p2i(current), p2i(continuation), p2i(pc));
620 }
621
622 return continuation;
623 JRT_END
624
625 // Enter this method from compiled code only if there is a Java exception handler
626 // in the method handling the exception.
627 // We are entering here from exception stub. We don't do a normal VM transition here.
628 // We do it in a helper. This is so we can check to see if the nmethod we have just
629 // searched for an exception handler has been deoptimized in the meantime.
630 address Runtime1::exception_handler_for_pc(JavaThread* current) {
631 oop exception = current->exception_oop();
632 address pc = current->exception_pc();
633 // Still in Java mode
634 DEBUG_ONLY(NoHandleMark nhm);
635 nmethod* nm = NULL;
636 address continuation = NULL;
637 {
638 // Enter VM mode by calling the helper
639 ResetNoHandleMark rnhm;
640 continuation = exception_handler_for_pc_helper(current, exception, pc, nm);
641 }
642 // Back in JAVA, use no oops DON'T safepoint
643
644 // Now check to see if the nmethod we were called from is now deoptimized.
645 // If so we must return to the deopt blob and deoptimize the nmethod
646 if (nm != NULL && caller_is_deopted(current)) {
647 continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
648 }
649
650 assert(continuation != NULL, "no handler found");
651 return continuation;
652 }
653
654
655 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* current, int index, arrayOopDesc* a))
656 NOT_PRODUCT(_throw_range_check_exception_count++;)
657 const int len = 35;
658 assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
659 char message[2 * jintAsStringSize + len];
660 sprintf(message, "Index %d out of bounds for length %d", index, a->length());
661 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
662 JRT_END
663
664
665 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* current, int index))
666 NOT_PRODUCT(_throw_index_exception_count++;)
667 char message[16];
668 sprintf(message, "%d", index);
669 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
670 JRT_END
671
672
673 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* current))
674 NOT_PRODUCT(_throw_div0_exception_count++;)
675 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
676 JRT_END
677
678
679 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* current))
680 NOT_PRODUCT(_throw_null_pointer_exception_count++;)
681 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_NullPointerException());
682 JRT_END
683
684
685 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* current, oopDesc* object))
686 NOT_PRODUCT(_throw_class_cast_exception_count++;)
687 ResourceMark rm(current);
688 char* message = SharedRuntime::generate_class_cast_message(current, object->klass());
689 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ClassCastException(), message);
690 JRT_END
691
692
693 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* current))
694 NOT_PRODUCT(_throw_incompatible_class_change_error_count++;)
695 ResourceMark rm(current);
696 SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IncompatibleClassChangeError());
697 JRT_END
698
699
700 JRT_BLOCK_ENTRY(void, Runtime1::monitorenter(JavaThread* current, oopDesc* obj, BasicObjectLock* lock))
701 NOT_PRODUCT(_monitorenter_slowcase_cnt++;)
702 if (LockingMode == LM_MONITOR) {
703 lock->set_obj(obj);
704 }
705 assert(LockingMode == LM_LIGHTWEIGHT || obj == lock->obj(), "must match");
706 SharedRuntime::monitor_enter_helper(obj, LockingMode == LM_LIGHTWEIGHT ? NULL : lock->lock(), current);
707 JRT_END
708
709
710 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* current, BasicObjectLock* lock))
711 NOT_PRODUCT(_monitorexit_slowcase_cnt++;)
712 assert(current->last_Java_sp(), "last_Java_sp must be set");
713 oop obj = lock->obj();
714 assert(oopDesc::is_oop(obj), "must be NULL or an object");
715 SharedRuntime::monitor_exit_helper(obj, lock->lock(), current);
716 JRT_END
717
718 // Cf. OptoRuntime::deoptimize_caller_frame
719 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* current, jint trap_request))
720 // Called from within the owner thread, so no need for safepoint
721 RegisterMap reg_map(current, false);
722 frame stub_frame = current->last_frame();
723 assert(stub_frame.is_runtime_frame(), "Sanity check");
724 frame caller_frame = stub_frame.sender(®_map);
725 nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
726 assert(nm != NULL, "Sanity check");
727 methodHandle method(current, nm->method());
728 assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
729 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
730 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
731
732 if (action == Deoptimization::Action_make_not_entrant) {
733 if (nm->make_not_entrant()) {
734 if (reason == Deoptimization::Reason_tenured) {
735 MethodData* trap_mdo = Deoptimization::get_method_data(current, method, true /*create_if_missing*/);
736 if (trap_mdo != NULL) {
737 trap_mdo->inc_tenure_traps();
738 }
739 }
740 }
741 }
742
743 // Deoptimize the caller frame.
744 Deoptimization::deoptimize_frame(current, caller_frame.id());
745 // Return to the now deoptimized frame.
746 JRT_END
747
748
749 #ifndef DEOPTIMIZE_WHEN_PATCHING
750
751 static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
752 Bytecode_field field_access(caller, bci);
753 // This can be static or non-static field access
754 Bytecodes::Code code = field_access.code();
755
756 // We must load class, initialize class and resolve the field
757 fieldDescriptor result; // initialize class if needed
758 constantPoolHandle constants(THREAD, caller->constants());
759 LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
760 return result.field_holder();
761 }
762
763
764 //
765 // This routine patches sites where a class wasn't loaded or
766 // initialized at the time the code was generated. It handles
767 // references to classes, fields and forcing of initialization. Most
768 // of the cases are straightforward and involving simply forcing
769 // resolution of a class, rewriting the instruction stream with the
770 // needed constant and replacing the call in this function with the
771 // patched code. The case for static field is more complicated since
772 // the thread which is in the process of initializing a class can
773 // access it's static fields but other threads can't so the code
774 // either has to deoptimize when this case is detected or execute a
775 // check that the current thread is the initializing thread. The
776 // current
777 //
778 // Patches basically look like this:
779 //
780 //
781 // patch_site: jmp patch stub ;; will be patched
782 // continue: ...
783 // ...
784 // ...
785 // ...
786 //
787 // They have a stub which looks like this:
788 //
789 // ;; patch body
790 // movl <const>, reg (for class constants)
791 // <or> movl [reg1 + <const>], reg (for field offsets)
792 // <or> movl reg, [reg1 + <const>] (for field offsets)
793 // <being_init offset> <bytes to copy> <bytes to skip>
794 // patch_stub: call Runtime1::patch_code (through a runtime stub)
795 // jmp patch_site
796 //
797 //
798 // A normal patch is done by rewriting the patch body, usually a move,
799 // and then copying it into place over top of the jmp instruction
800 // being careful to flush caches and doing it in an MP-safe way. The
801 // constants following the patch body are used to find various pieces
802 // of the patch relative to the call site for Runtime1::patch_code.
803 // The case for getstatic and putstatic is more complicated because
804 // getstatic and putstatic have special semantics when executing while
805 // the class is being initialized. getstatic/putstatic on a class
806 // which is being_initialized may be executed by the initializing
807 // thread but other threads have to block when they execute it. This
808 // is accomplished in compiled code by executing a test of the current
809 // thread against the initializing thread of the class. It's emitted
810 // as boilerplate in their stub which allows the patched code to be
811 // executed before it's copied back into the main body of the nmethod.
812 //
813 // being_init: get_thread(<tmp reg>
814 // cmpl [reg1 + <init_thread_offset>], <tmp reg>
815 // jne patch_stub
816 // movl [reg1 + <const>], reg (for field offsets) <or>
817 // movl reg, [reg1 + <const>] (for field offsets)
818 // jmp continue
819 // <being_init offset> <bytes to copy> <bytes to skip>
820 // patch_stub: jmp Runtim1::patch_code (through a runtime stub)
821 // jmp patch_site
822 //
823 // If the class is being initialized the patch body is rewritten and
824 // the patch site is rewritten to jump to being_init, instead of
825 // patch_stub. Whenever this code is executed it checks the current
826 // thread against the intializing thread so other threads will enter
827 // the runtime and end up blocked waiting the class to finish
828 // initializing inside the calls to resolve_field below. The
829 // initializing class will continue on it's way. Once the class is
830 // fully_initialized, the intializing_thread of the class becomes
831 // NULL, so the next thread to execute this code will fail the test,
832 // call into patch_code and complete the patching process by copying
833 // the patch body back into the main part of the nmethod and resume
834 // executing.
835
836 // NB:
837 //
838 // Patchable instruction sequences inherently exhibit race conditions,
839 // where thread A is patching an instruction at the same time thread B
840 // is executing it. The algorithms we use ensure that any observation
841 // that B can make on any intermediate states during A's patching will
842 // always end up with a correct outcome. This is easiest if there are
843 // few or no intermediate states. (Some inline caches have two
844 // related instructions that must be patched in tandem. For those,
845 // intermediate states seem to be unavoidable, but we will get the
846 // right answer from all possible observation orders.)
847 //
848 // When patching the entry instruction at the head of a method, or a
849 // linkable call instruction inside of a method, we try very hard to
850 // use a patch sequence which executes as a single memory transaction.
851 // This means, in practice, that when thread A patches an instruction,
852 // it should patch a 32-bit or 64-bit word that somehow overlaps the
853 // instruction or is contained in it. We believe that memory hardware
854 // will never break up such a word write, if it is naturally aligned
855 // for the word being written. We also know that some CPUs work very
856 // hard to create atomic updates even of naturally unaligned words,
857 // but we don't want to bet the farm on this always working.
858 //
859 // Therefore, if there is any chance of a race condition, we try to
860 // patch only naturally aligned words, as single, full-word writes.
861
862 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* current, Runtime1::StubID stub_id ))
863 NOT_PRODUCT(_patch_code_slowcase_cnt++;)
864
865 ResourceMark rm(current);
866 RegisterMap reg_map(current, false);
867 frame runtime_frame = current->last_frame();
868 frame caller_frame = runtime_frame.sender(®_map);
869
870 // last java frame on stack
871 vframeStream vfst(current, true);
872 assert(!vfst.at_end(), "Java frame must exist");
873
874 methodHandle caller_method(current, vfst.method());
875 // Note that caller_method->code() may not be same as caller_code because of OSR's
876 // Note also that in the presence of inlining it is not guaranteed
877 // that caller_method() == caller_code->method()
878
879 int bci = vfst.bci();
880 Bytecodes::Code code = caller_method()->java_code_at(bci);
881
882 // this is used by assertions in the access_field_patching_id
883 BasicType patch_field_type = T_ILLEGAL;
884 bool deoptimize_for_volatile = false;
885 bool deoptimize_for_atomic = false;
886 int patch_field_offset = -1;
887 Klass* init_klass = NULL; // klass needed by load_klass_patching code
888 Klass* load_klass = NULL; // klass needed by load_klass_patching code
889 Handle mirror(current, NULL); // oop needed by load_mirror_patching code
890 Handle appendix(current, NULL); // oop needed by appendix_patching code
891 bool load_klass_or_mirror_patch_id =
892 (stub_id == Runtime1::load_klass_patching_id || stub_id == Runtime1::load_mirror_patching_id);
893
894 if (stub_id == Runtime1::access_field_patching_id) {
895
896 Bytecode_field field_access(caller_method, bci);
897 fieldDescriptor result; // initialize class if needed
898 Bytecodes::Code code = field_access.code();
899 constantPoolHandle constants(current, caller_method->constants());
900 LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
901 patch_field_offset = result.offset();
902
903 // If we're patching a field which is volatile then at compile it
904 // must not have been know to be volatile, so the generated code
905 // isn't correct for a volatile reference. The nmethod has to be
906 // deoptimized so that the code can be regenerated correctly.
907 // This check is only needed for access_field_patching since this
908 // is the path for patching field offsets. load_klass is only
909 // used for patching references to oops which don't need special
910 // handling in the volatile case.
911
912 deoptimize_for_volatile = result.access_flags().is_volatile();
913
914 // If we are patching a field which should be atomic, then
915 // the generated code is not correct either, force deoptimizing.
916 // We need to only cover T_LONG and T_DOUBLE fields, as we can
917 // break access atomicity only for them.
918
919 // Strictly speaking, the deoptimization on 64-bit platforms
920 // is unnecessary, and T_LONG stores on 32-bit platforms need
921 // to be handled by special patching code when AlwaysAtomicAccesses
922 // becomes product feature. At this point, we are still going
923 // for the deoptimization for consistency against volatile
924 // accesses.
925
926 patch_field_type = result.field_type();
927 deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
928
929 } else if (load_klass_or_mirror_patch_id) {
930 Klass* k = NULL;
931 switch (code) {
932 case Bytecodes::_putstatic:
933 case Bytecodes::_getstatic:
934 { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
935 init_klass = klass;
936 mirror = Handle(current, klass->java_mirror());
937 }
938 break;
939 case Bytecodes::_new:
940 { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
941 k = caller_method->constants()->klass_at(bnew.index(), CHECK);
942 }
943 break;
944 case Bytecodes::_multianewarray:
945 { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
946 k = caller_method->constants()->klass_at(mna.index(), CHECK);
947 }
948 break;
949 case Bytecodes::_instanceof:
950 { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
951 k = caller_method->constants()->klass_at(io.index(), CHECK);
952 }
953 break;
954 case Bytecodes::_checkcast:
955 { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
956 k = caller_method->constants()->klass_at(cc.index(), CHECK);
957 }
958 break;
959 case Bytecodes::_anewarray:
960 { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
961 Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
962 k = ek->array_klass(CHECK);
963 }
964 break;
965 case Bytecodes::_ldc:
966 case Bytecodes::_ldc_w:
967 {
968 Bytecode_loadconstant cc(caller_method, bci);
969 oop m = cc.resolve_constant(CHECK);
970 mirror = Handle(current, m);
971 }
972 break;
973 default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
974 }
975 load_klass = k;
976 } else if (stub_id == load_appendix_patching_id) {
977 Bytecode_invoke bytecode(caller_method, bci);
978 Bytecodes::Code bc = bytecode.invoke_code();
979
980 CallInfo info;
981 constantPoolHandle pool(current, caller_method->constants());
982 int index = bytecode.index();
983 LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
984 switch (bc) {
985 case Bytecodes::_invokehandle: {
986 int cache_index = ConstantPool::decode_cpcache_index(index, true);
987 assert(cache_index >= 0 && cache_index < pool->cache()->length(), "unexpected cache index");
988 ConstantPoolCacheEntry* cpce = pool->cache()->entry_at(cache_index);
989 cpce->set_method_handle(pool, info);
990 appendix = Handle(current, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
991 break;
992 }
993 case Bytecodes::_invokedynamic: {
994 ConstantPoolCacheEntry* cpce = pool->invokedynamic_cp_cache_entry_at(index);
995 cpce->set_dynamic_call(pool, info);
996 appendix = Handle(current, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
997 break;
998 }
999 default: fatal("unexpected bytecode for load_appendix_patching_id");
1000 }
1001 } else {
1002 ShouldNotReachHere();
1003 }
1004
1005 if (deoptimize_for_volatile || deoptimize_for_atomic) {
1006 // At compile time we assumed the field wasn't volatile/atomic but after
1007 // loading it turns out it was volatile/atomic so we have to throw the
1008 // compiled code out and let it be regenerated.
1009 if (TracePatching) {
1010 if (deoptimize_for_volatile) {
1011 tty->print_cr("Deoptimizing for patching volatile field reference");
1012 }
1013 if (deoptimize_for_atomic) {
1014 tty->print_cr("Deoptimizing for patching atomic field reference");
1015 }
1016 }
1017
1018 // It's possible the nmethod was invalidated in the last
1019 // safepoint, but if it's still alive then make it not_entrant.
1020 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1021 if (nm != NULL) {
1022 nm->make_not_entrant();
1023 }
1024
1025 Deoptimization::deoptimize_frame(current, caller_frame.id());
1026
1027 // Return to the now deoptimized frame.
1028 }
1029
1030 // Now copy code back
1031
1032 {
1033 MutexLocker ml_patch (current, Patching_lock, Mutex::_no_safepoint_check_flag);
1034 //
1035 // Deoptimization may have happened while we waited for the lock.
1036 // In that case we don't bother to do any patching we just return
1037 // and let the deopt happen
1038 if (!caller_is_deopted(current)) {
1039 NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
1040 address instr_pc = jump->jump_destination();
1041 NativeInstruction* ni = nativeInstruction_at(instr_pc);
1042 if (ni->is_jump() ) {
1043 // the jump has not been patched yet
1044 // The jump destination is slow case and therefore not part of the stubs
1045 // (stubs are only for StaticCalls)
1046
1047 // format of buffer
1048 // ....
1049 // instr byte 0 <-- copy_buff
1050 // instr byte 1
1051 // ..
1052 // instr byte n-1
1053 // n
1054 // .... <-- call destination
1055
1056 address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
1057 unsigned char* byte_count = (unsigned char*) (stub_location - 1);
1058 unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
1059 unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
1060 address copy_buff = stub_location - *byte_skip - *byte_count;
1061 address being_initialized_entry = stub_location - *being_initialized_entry_offset;
1062 if (TracePatching) {
1063 ttyLocker ttyl;
1064 tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT " (%s)", Bytecodes::name(code), bci,
1065 p2i(instr_pc), (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
1066 nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
1067 assert(caller_code != NULL, "nmethod not found");
1068
1069 // NOTE we use pc() not original_pc() because we already know they are
1070 // identical otherwise we'd have never entered this block of code
1071
1072 const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
1073 assert(map != NULL, "null check");
1074 map->print();
1075 tty->cr();
1076
1077 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1078 }
1079 // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
1080 bool do_patch = true;
1081 if (stub_id == Runtime1::access_field_patching_id) {
1082 // The offset may not be correct if the class was not loaded at code generation time.
1083 // Set it now.
1084 NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
1085 assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1086 assert(patch_field_offset >= 0, "illegal offset");
1087 n_move->add_offset_in_bytes(patch_field_offset);
1088 } else if (load_klass_or_mirror_patch_id) {
1089 // If a getstatic or putstatic is referencing a klass which
1090 // isn't fully initialized, the patch body isn't copied into
1091 // place until initialization is complete. In this case the
1092 // patch site is setup so that any threads besides the
1093 // initializing thread are forced to come into the VM and
1094 // block.
1095 do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1096 InstanceKlass::cast(init_klass)->is_initialized();
1097 NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1098 if (jump->jump_destination() == being_initialized_entry) {
1099 assert(do_patch == true, "initialization must be complete at this point");
1100 } else {
1101 // patch the instruction <move reg, klass>
1102 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1103
1104 assert(n_copy->data() == 0 ||
1105 n_copy->data() == (intptr_t)Universe::non_oop_word(),
1106 "illegal init value");
1107 if (stub_id == Runtime1::load_klass_patching_id) {
1108 assert(load_klass != NULL, "klass not set");
1109 n_copy->set_data((intx) (load_klass));
1110 } else {
1111 assert(mirror() != NULL, "klass not set");
1112 // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1113 n_copy->set_data(cast_from_oop<intx>(mirror()));
1114 }
1115
1116 if (TracePatching) {
1117 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1118 }
1119 }
1120 } else if (stub_id == Runtime1::load_appendix_patching_id) {
1121 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1122 assert(n_copy->data() == 0 ||
1123 n_copy->data() == (intptr_t)Universe::non_oop_word(),
1124 "illegal init value");
1125 n_copy->set_data(cast_from_oop<intx>(appendix()));
1126
1127 if (TracePatching) {
1128 Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1129 }
1130 } else {
1131 ShouldNotReachHere();
1132 }
1133
1134 #if defined(PPC32)
1135 if (load_klass_or_mirror_patch_id ||
1136 stub_id == Runtime1::load_appendix_patching_id) {
1137 // Update the location in the nmethod with the proper
1138 // metadata. When the code was generated, a NULL was stuffed
1139 // in the metadata table and that table needs to be update to
1140 // have the right value. On intel the value is kept
1141 // directly in the instruction instead of in the metadata
1142 // table, so set_data above effectively updated the value.
1143 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1144 assert(nm != NULL, "invalid nmethod_pc");
1145 RelocIterator mds(nm, copy_buff, copy_buff + 1);
1146 bool found = false;
1147 while (mds.next() && !found) {
1148 if (mds.type() == relocInfo::oop_type) {
1149 assert(stub_id == Runtime1::load_mirror_patching_id ||
1150 stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1151 oop_Relocation* r = mds.oop_reloc();
1152 oop* oop_adr = r->oop_addr();
1153 *oop_adr = stub_id == Runtime1::load_mirror_patching_id ? mirror() : appendix();
1154 r->fix_oop_relocation();
1155 found = true;
1156 } else if (mds.type() == relocInfo::metadata_type) {
1157 assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1158 metadata_Relocation* r = mds.metadata_reloc();
1159 Metadata** metadata_adr = r->metadata_addr();
1160 *metadata_adr = load_klass;
1161 r->fix_metadata_relocation();
1162 found = true;
1163 }
1164 }
1165 assert(found, "the metadata must exist!");
1166 }
1167 #endif
1168 if (do_patch) {
1169 // replace instructions
1170 // first replace the tail, then the call
1171 #ifdef ARM
1172 if((load_klass_or_mirror_patch_id ||
1173 stub_id == Runtime1::load_appendix_patching_id) &&
1174 nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1175 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1176 address addr = NULL;
1177 assert(nm != NULL, "invalid nmethod_pc");
1178 RelocIterator mds(nm, copy_buff, copy_buff + 1);
1179 while (mds.next()) {
1180 if (mds.type() == relocInfo::oop_type) {
1181 assert(stub_id == Runtime1::load_mirror_patching_id ||
1182 stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1183 oop_Relocation* r = mds.oop_reloc();
1184 addr = (address)r->oop_addr();
1185 break;
1186 } else if (mds.type() == relocInfo::metadata_type) {
1187 assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1188 metadata_Relocation* r = mds.metadata_reloc();
1189 addr = (address)r->metadata_addr();
1190 break;
1191 }
1192 }
1193 assert(addr != NULL, "metadata relocation must exist");
1194 copy_buff -= *byte_count;
1195 NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1196 n_copy2->set_pc_relative_offset(addr, instr_pc);
1197 }
1198 #endif
1199
1200 for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
1201 address ptr = copy_buff + i;
1202 int a_byte = (*ptr) & 0xFF;
1203 address dst = instr_pc + i;
1204 *(unsigned char*)dst = (unsigned char) a_byte;
1205 }
1206 ICache::invalidate_range(instr_pc, *byte_count);
1207 NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1208
1209 if (load_klass_or_mirror_patch_id ||
1210 stub_id == Runtime1::load_appendix_patching_id) {
1211 relocInfo::relocType rtype =
1212 (stub_id == Runtime1::load_klass_patching_id) ?
1213 relocInfo::metadata_type :
1214 relocInfo::oop_type;
1215 // update relocInfo to metadata
1216 nmethod* nm = CodeCache::find_nmethod(instr_pc);
1217 assert(nm != NULL, "invalid nmethod_pc");
1218
1219 // The old patch site is now a move instruction so update
1220 // the reloc info so that it will get updated during
1221 // future GCs.
1222 RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1223 relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1224 relocInfo::none, rtype);
1225 #ifdef PPC32
1226 { address instr_pc2 = instr_pc + NativeMovConstReg::lo_offset;
1227 RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1228 relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1229 relocInfo::none, rtype);
1230 }
1231 #endif
1232 }
1233
1234 } else {
1235 ICache::invalidate_range(copy_buff, *byte_count);
1236 NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1237 }
1238 }
1239 }
1240 }
1241
1242 // If we are patching in a non-perm oop, make sure the nmethod
1243 // is on the right list.
1244 {
1245 MutexLocker ml_code (current, CodeCache_lock, Mutex::_no_safepoint_check_flag);
1246 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1247 guarantee(nm != NULL, "only nmethods can contain non-perm oops");
1248
1249 // Since we've patched some oops in the nmethod,
1250 // (re)register it with the heap.
1251 Universe::heap()->register_nmethod(nm);
1252 }
1253 JRT_END
1254
1255 #else // DEOPTIMIZE_WHEN_PATCHING
1256
1257 static bool is_patching_needed(JavaThread* current, Runtime1::StubID stub_id) {
1258 if (stub_id == Runtime1::load_klass_patching_id ||
1259 stub_id == Runtime1::load_mirror_patching_id) {
1260 // last java frame on stack
1261 vframeStream vfst(current, true);
1262 assert(!vfst.at_end(), "Java frame must exist");
1263
1264 methodHandle caller_method(current, vfst.method());
1265 int bci = vfst.bci();
1266 Bytecodes::Code code = caller_method()->java_code_at(bci);
1267
1268 switch (code) {
1269 case Bytecodes::_new:
1270 case Bytecodes::_anewarray:
1271 case Bytecodes::_multianewarray:
1272 case Bytecodes::_instanceof:
1273 case Bytecodes::_checkcast: {
1274 Bytecode bc(caller_method(), caller_method->bcp_from(bci));
1275 constantTag tag = caller_method->constants()->tag_at(bc.get_index_u2(code));
1276 if (tag.is_unresolved_klass_in_error()) {
1277 return false; // throws resolution error
1278 }
1279 break;
1280 }
1281
1282 default: break;
1283 }
1284 }
1285 return true;
1286 }
1287
1288 void Runtime1::patch_code(JavaThread* current, Runtime1::StubID stub_id) {
1289 NOT_PRODUCT(_patch_code_slowcase_cnt++);
1290
1291 // Enable WXWrite: the function is called by c1 stub as a runtime function
1292 // (see another implementation above).
1293 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
1294
1295 if (TracePatching) {
1296 tty->print_cr("Deoptimizing because patch is needed");
1297 }
1298
1299 RegisterMap reg_map(current, false);
1300
1301 frame runtime_frame = current->last_frame();
1302 frame caller_frame = runtime_frame.sender(®_map);
1303 assert(caller_frame.is_compiled_frame(), "Wrong frame type");
1304
1305 if (is_patching_needed(current, stub_id)) {
1306 // Make sure the nmethod is invalidated, i.e. made not entrant.
1307 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1308 if (nm != NULL) {
1309 nm->make_not_entrant();
1310 }
1311 }
1312
1313 Deoptimization::deoptimize_frame(current, caller_frame.id());
1314 // Return to the now deoptimized frame.
1315 postcond(caller_is_deopted(current));
1316 }
1317
1318 #endif // DEOPTIMIZE_WHEN_PATCHING
1319
1320 // Entry point for compiled code. We want to patch a nmethod.
1321 // We don't do a normal VM transition here because we want to
1322 // know after the patching is complete and any safepoint(s) are taken
1323 // if the calling nmethod was deoptimized. We do this by calling a
1324 // helper method which does the normal VM transition and when it
1325 // completes we can check for deoptimization. This simplifies the
1326 // assembly code in the cpu directories.
1327 //
1328 int Runtime1::move_klass_patching(JavaThread* current) {
1329 //
1330 // NOTE: we are still in Java
1331 //
1332 debug_only(NoHandleMark nhm;)
1333 {
1334 // Enter VM mode
1335 ResetNoHandleMark rnhm;
1336 patch_code(current, load_klass_patching_id);
1337 }
1338 // Back in JAVA, use no oops DON'T safepoint
1339
1340 // Return true if calling code is deoptimized
1341
1342 return caller_is_deopted(current);
1343 }
1344
1345 int Runtime1::move_mirror_patching(JavaThread* current) {
1346 //
1347 // NOTE: we are still in Java
1348 //
1349 debug_only(NoHandleMark nhm;)
1350 {
1351 // Enter VM mode
1352 ResetNoHandleMark rnhm;
1353 patch_code(current, load_mirror_patching_id);
1354 }
1355 // Back in JAVA, use no oops DON'T safepoint
1356
1357 // Return true if calling code is deoptimized
1358
1359 return caller_is_deopted(current);
1360 }
1361
1362 int Runtime1::move_appendix_patching(JavaThread* current) {
1363 //
1364 // NOTE: we are still in Java
1365 //
1366 debug_only(NoHandleMark nhm;)
1367 {
1368 // Enter VM mode
1369 ResetNoHandleMark rnhm;
1370 patch_code(current, load_appendix_patching_id);
1371 }
1372 // Back in JAVA, use no oops DON'T safepoint
1373
1374 // Return true if calling code is deoptimized
1375
1376 return caller_is_deopted(current);
1377 }
1378
1379 // Entry point for compiled code. We want to patch a nmethod.
1380 // We don't do a normal VM transition here because we want to
1381 // know after the patching is complete and any safepoint(s) are taken
1382 // if the calling nmethod was deoptimized. We do this by calling a
1383 // helper method which does the normal VM transition and when it
1384 // completes we can check for deoptimization. This simplifies the
1385 // assembly code in the cpu directories.
1386 //
1387 int Runtime1::access_field_patching(JavaThread* current) {
1388 //
1389 // NOTE: we are still in Java
1390 //
1391 // Handles created in this function will be deleted by the
1392 // HandleMarkCleaner in the transition to the VM.
1393 NoHandleMark nhm;
1394 {
1395 // Enter VM mode
1396 ResetNoHandleMark rnhm;
1397 patch_code(current, access_field_patching_id);
1398 }
1399 // Back in JAVA, use no oops DON'T safepoint
1400
1401 // Return true if calling code is deoptimized
1402
1403 return caller_is_deopted(current);
1404 }
1405
1406
1407 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1408 // for now we just print out the block id
1409 tty->print("%d ", block_id);
1410 JRT_END
1411
1412
1413 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1414 // had to return int instead of bool, otherwise there may be a mismatch
1415 // between the C calling convention and the Java one.
1416 // e.g., on x86, GCC may clear only %al when returning a bool false, but
1417 // JVM takes the whole %eax as the return value, which may misinterpret
1418 // the return value as a boolean true.
1419
1420 assert(mirror != NULL, "should null-check on mirror before calling");
1421 Klass* k = java_lang_Class::as_Klass(mirror);
1422 return (k != NULL && obj != NULL && obj->is_a(k)) ? 1 : 0;
1423 JRT_END
1424
1425 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* current))
1426 ResourceMark rm;
1427
1428 RegisterMap reg_map(current, false);
1429 frame runtime_frame = current->last_frame();
1430 frame caller_frame = runtime_frame.sender(®_map);
1431
1432 nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1433 assert (nm != NULL, "no more nmethod?");
1434 nm->make_not_entrant();
1435
1436 methodHandle m(current, nm->method());
1437 MethodData* mdo = m->method_data();
1438
1439 if (mdo == NULL && !HAS_PENDING_EXCEPTION) {
1440 // Build an MDO. Ignore errors like OutOfMemory;
1441 // that simply means we won't have an MDO to update.
1442 Method::build_interpreter_method_data(m, THREAD);
1443 if (HAS_PENDING_EXCEPTION) {
1444 // Only metaspace OOM is expected. No Java code executed.
1445 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1446 CLEAR_PENDING_EXCEPTION;
1447 }
1448 mdo = m->method_data();
1449 }
1450
1451 if (mdo != NULL) {
1452 mdo->inc_trap_count(Deoptimization::Reason_none);
1453 }
1454
1455 if (TracePredicateFailedTraps) {
1456 stringStream ss1, ss2;
1457 vframeStream vfst(current);
1458 Method* inlinee = vfst.method();
1459 inlinee->print_short_name(&ss1);
1460 m->print_short_name(&ss2);
1461 tty->print_cr("Predicate failed trap in method %s at bci %d inlined in %s at pc " INTPTR_FORMAT, ss1.as_string(), vfst.bci(), ss2.as_string(), p2i(caller_frame.pc()));
1462 }
1463
1464
1465 Deoptimization::deoptimize_frame(current, caller_frame.id());
1466
1467 JRT_END
1468
1469 #ifndef PRODUCT
1470 void Runtime1::print_statistics() {
1471 tty->print_cr("C1 Runtime statistics:");
1472 tty->print_cr(" _resolve_invoke_virtual_cnt: %d", SharedRuntime::_resolve_virtual_ctr);
1473 tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %d", SharedRuntime::_resolve_opt_virtual_ctr);
1474 tty->print_cr(" _resolve_invoke_static_cnt: %d", SharedRuntime::_resolve_static_ctr);
1475 tty->print_cr(" _handle_wrong_method_cnt: %d", SharedRuntime::_wrong_method_ctr);
1476 tty->print_cr(" _ic_miss_cnt: %d", SharedRuntime::_ic_miss_ctr);
1477 tty->print_cr(" _generic_arraycopystub_cnt: %d", _generic_arraycopystub_cnt);
1478 tty->print_cr(" _byte_arraycopy_cnt: %d", _byte_arraycopy_stub_cnt);
1479 tty->print_cr(" _short_arraycopy_cnt: %d", _short_arraycopy_stub_cnt);
1480 tty->print_cr(" _int_arraycopy_cnt: %d", _int_arraycopy_stub_cnt);
1481 tty->print_cr(" _long_arraycopy_cnt: %d", _long_arraycopy_stub_cnt);
1482 tty->print_cr(" _oop_arraycopy_cnt: %d", _oop_arraycopy_stub_cnt);
1483 tty->print_cr(" _arraycopy_slowcase_cnt: %d", _arraycopy_slowcase_cnt);
1484 tty->print_cr(" _arraycopy_checkcast_cnt: %d", _arraycopy_checkcast_cnt);
1485 tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%d", _arraycopy_checkcast_attempt_cnt);
1486
1487 tty->print_cr(" _new_type_array_slowcase_cnt: %d", _new_type_array_slowcase_cnt);
1488 tty->print_cr(" _new_object_array_slowcase_cnt: %d", _new_object_array_slowcase_cnt);
1489 tty->print_cr(" _new_instance_slowcase_cnt: %d", _new_instance_slowcase_cnt);
1490 tty->print_cr(" _new_multi_array_slowcase_cnt: %d", _new_multi_array_slowcase_cnt);
1491 tty->print_cr(" _monitorenter_slowcase_cnt: %d", _monitorenter_slowcase_cnt);
1492 tty->print_cr(" _monitorexit_slowcase_cnt: %d", _monitorexit_slowcase_cnt);
1493 tty->print_cr(" _patch_code_slowcase_cnt: %d", _patch_code_slowcase_cnt);
1494
1495 tty->print_cr(" _throw_range_check_exception_count: %d:", _throw_range_check_exception_count);
1496 tty->print_cr(" _throw_index_exception_count: %d:", _throw_index_exception_count);
1497 tty->print_cr(" _throw_div0_exception_count: %d:", _throw_div0_exception_count);
1498 tty->print_cr(" _throw_null_pointer_exception_count: %d:", _throw_null_pointer_exception_count);
1499 tty->print_cr(" _throw_class_cast_exception_count: %d:", _throw_class_cast_exception_count);
1500 tty->print_cr(" _throw_incompatible_class_change_error_count: %d:", _throw_incompatible_class_change_error_count);
1501 tty->print_cr(" _throw_count: %d:", _throw_count);
1502
1503 SharedRuntime::print_ic_miss_histogram();
1504 tty->cr();
1505 }
1506 #endif // PRODUCT