1 /*
2 * Copyright (c) 2012, 2013, 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
27 #include "memory/universe.hpp"
28 #include "oops/oop.inline.hpp"
29
30 #include "classfile/symbolTable.hpp"
31 #include "classfile/classLoaderData.hpp"
32
33 #include "prims/whitebox.hpp"
34 #include "prims/wbtestmethods/parserTests.hpp"
35
36 #include "runtime/arguments.hpp"
37 #include "runtime/interfaceSupport.hpp"
38 #include "runtime/os.hpp"
39 #include "utilities/debug.hpp"
40 #include "utilities/macros.hpp"
41 #include "utilities/exceptions.hpp"
42
43 #if INCLUDE_ALL_GCS
44 #include "gc_implementation/g1/concurrentMark.hpp"
45 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
46 #include "gc_implementation/g1/heapRegionRemSet.hpp"
47 #endif // INCLUDE_ALL_GCS
48
49 #ifdef INCLUDE_NMT
50 #include "services/memTracker.hpp"
51 #endif // INCLUDE_NMT
52
53 #include "compiler/compileBroker.hpp"
54 #include "runtime/compilationPolicy.hpp"
55
56 bool WhiteBox::_used = false;
57
58 WB_ENTRY(jlong, WB_GetObjectAddress(JNIEnv* env, jobject o, jobject obj))
59 return (jlong)(void*)JNIHandles::resolve(obj);
60 WB_END
61
62 WB_ENTRY(jint, WB_GetHeapOopSize(JNIEnv* env, jobject o))
63 return heapOopSize;
64 WB_END
65
66
67 class WBIsKlassAliveClosure : public KlassClosure {
68 Symbol* _name;
69 bool _found;
70 public:
71 WBIsKlassAliveClosure(Symbol* name) : _name(name), _found(false) {}
72
73 void do_klass(Klass* k) {
74 if (_found) return;
75 Symbol* ksym = k->name();
76 if (ksym->fast_compare(_name) == 0) {
77 _found = true;
78 }
79 }
80
81 bool found() const {
82 return _found;
83 }
84 };
85
86 WB_ENTRY(jboolean, WB_IsClassAlive(JNIEnv* env, jobject target, jstring name))
87 Handle h_name = JNIHandles::resolve(name);
88 if (h_name.is_null()) return false;
89 Symbol* sym = java_lang_String::as_symbol(h_name, CHECK_false);
90 TempNewSymbol tsym(sym); // Make sure to decrement reference count on sym on return
91
92 WBIsKlassAliveClosure closure(sym);
93 ClassLoaderDataGraph::classes_do(&closure);
94
95 return closure.found();
96 WB_END
97
98 WB_ENTRY(void, WB_PrintCompressedOopsHeapInfo(JNIEnv* env, jobject o)) {
99 gclog_or_tty->print_cr("Max heap for compressed oops "SIZE_FORMAT" ClassMetaspaceSize "SIZE_FORMAT,
100 Arguments::max_heap_for_compressed_oops(), ClassMetaspaceSize);
101 }
102 WB_END
103
104 WB_ENTRY(void, WB_PrintHeapSizes(JNIEnv* env, jobject o)) {
105 CollectorPolicy * p = Universe::heap()->collector_policy();
106 gclog_or_tty->print_cr("Minimum heap "SIZE_FORMAT" Initial heap "
107 SIZE_FORMAT" Maximum heap "SIZE_FORMAT" Min alignment "SIZE_FORMAT" Max alignment "SIZE_FORMAT,
108 p->min_heap_byte_size(), p->initial_heap_byte_size(), p->max_heap_byte_size(),
109 p->min_alignment(), p->max_alignment());
110 }
111 WB_END
112
113 #if INCLUDE_ALL_GCS
114 WB_ENTRY(jboolean, WB_G1IsHumongous(JNIEnv* env, jobject o, jobject obj))
115 G1CollectedHeap* g1 = G1CollectedHeap::heap();
116 oop result = JNIHandles::resolve(obj);
117 const HeapRegion* hr = g1->heap_region_containing(result);
118 return hr->isHumongous();
119 WB_END
120
121 WB_ENTRY(jlong, WB_G1NumFreeRegions(JNIEnv* env, jobject o))
122 G1CollectedHeap* g1 = G1CollectedHeap::heap();
123 size_t nr = g1->free_regions();
124 return (jlong)nr;
125 WB_END
126
127 WB_ENTRY(jboolean, WB_G1InConcurrentMark(JNIEnv* env, jobject o))
128 G1CollectedHeap* g1 = G1CollectedHeap::heap();
129 ConcurrentMark* cm = g1->concurrent_mark();
130 return cm->concurrent_marking_in_progress();
131 WB_END
132
133 WB_ENTRY(jint, WB_G1RegionSize(JNIEnv* env, jobject o))
134 return (jint)HeapRegion::GrainBytes;
135 WB_END
136 #endif // INCLUDE_ALL_GCS
137
138 #ifdef INCLUDE_NMT
139 // Alloc memory using the test memory type so that we can use that to see if
140 // NMT picks it up correctly
141 WB_ENTRY(jlong, WB_NMTMalloc(JNIEnv* env, jobject o, jlong size))
142 jlong addr = 0;
143
144 if (MemTracker::is_on() && !MemTracker::shutdown_in_progress()) {
145 addr = (jlong)(uintptr_t)os::malloc(size, mtTest);
146 }
147
148 return addr;
149 WB_END
150
151 // Free the memory allocated by NMTAllocTest
152 WB_ENTRY(void, WB_NMTFree(JNIEnv* env, jobject o, jlong mem))
153 os::free((void*)(uintptr_t)mem, mtTest);
154 WB_END
155
156 WB_ENTRY(jlong, WB_NMTReserveMemory(JNIEnv* env, jobject o, jlong size))
157 jlong addr = 0;
158
159 if (MemTracker::is_on() && !MemTracker::shutdown_in_progress()) {
160 addr = (jlong)(uintptr_t)os::reserve_memory(size);
161 MemTracker::record_virtual_memory_type((address)addr, mtTest);
162 }
163
164 return addr;
165 WB_END
166
167
168 WB_ENTRY(void, WB_NMTCommitMemory(JNIEnv* env, jobject o, jlong addr, jlong size))
169 os::commit_memory((char *)(uintptr_t)addr, size, !ExecMem);
170 MemTracker::record_virtual_memory_type((address)(uintptr_t)addr, mtTest);
171 WB_END
172
173 WB_ENTRY(void, WB_NMTUncommitMemory(JNIEnv* env, jobject o, jlong addr, jlong size))
174 os::uncommit_memory((char *)(uintptr_t)addr, size);
175 WB_END
176
177 WB_ENTRY(void, WB_NMTReleaseMemory(JNIEnv* env, jobject o, jlong addr, jlong size))
178 os::release_memory((char *)(uintptr_t)addr, size);
179 WB_END
180
181 // Block until the current generation of NMT data to be merged, used to reliably test the NMT feature
182 WB_ENTRY(jboolean, WB_NMTWaitForDataMerge(JNIEnv* env))
183
184 if (!MemTracker::is_on() || MemTracker::shutdown_in_progress()) {
185 return false;
186 }
187
188 return MemTracker::wbtest_wait_for_data_merge();
189 WB_END
190
191 #endif // INCLUDE_NMT
192
193 static jmethodID reflected_method_to_jmid(JavaThread* thread, JNIEnv* env, jobject method) {
194 assert(method != NULL, "method should not be null");
195 ThreadToNativeFromVM ttn(thread);
196 return env->FromReflectedMethod(method);
197 }
198
199 WB_ENTRY(void, WB_DeoptimizeAll(JNIEnv* env, jobject o))
200 MutexLockerEx mu(Compile_lock);
201 CodeCache::mark_all_nmethods_for_deoptimization();
202 VM_Deoptimize op;
203 VMThread::execute(&op);
204 WB_END
205
206 WB_ENTRY(jint, WB_DeoptimizeMethod(JNIEnv* env, jobject o, jobject method, jboolean is_osr))
207 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
208 MutexLockerEx mu(Compile_lock);
209 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
210 int result = 0;
211 nmethod* code;
212 if (is_osr) {
213 int bci = InvocationEntryBci;
214 while ((code = mh->lookup_osr_nmethod_for(bci, CompLevel_none, false)) != NULL) {
215 code->mark_for_deoptimization();
216 ++result;
217 bci = code->osr_entry_bci() + 1;
218 }
219 } else {
220 code = mh->code();
221 }
222 if (code != NULL) {
223 code->mark_for_deoptimization();
224 ++result;
225 }
226 result += CodeCache::mark_for_deoptimization(mh());
227 if (result > 0) {
228 VM_Deoptimize op;
229 VMThread::execute(&op);
230 }
231 return result;
232 WB_END
233
234 WB_ENTRY(jboolean, WB_IsMethodCompiled(JNIEnv* env, jobject o, jobject method, jboolean is_osr))
235 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
236 MutexLockerEx mu(Compile_lock);
237 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
238 nmethod* code = is_osr ? mh->lookup_osr_nmethod_for(InvocationEntryBci, CompLevel_none, false) : mh->code();
239 if (code == NULL) {
240 return JNI_FALSE;
241 }
242 return (code->is_alive() && !code->is_marked_for_deoptimization());
243 WB_END
244
245 WB_ENTRY(jboolean, WB_IsMethodCompilable(JNIEnv* env, jobject o, jobject method, jint comp_level, jboolean is_osr))
246 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
247 MutexLockerEx mu(Compile_lock);
248 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
249 if (is_osr) {
250 return CompilationPolicy::can_be_osr_compiled(mh, comp_level);
251 } else {
252 return CompilationPolicy::can_be_compiled(mh, comp_level);
253 }
254 WB_END
255
256 WB_ENTRY(jboolean, WB_IsMethodQueuedForCompilation(JNIEnv* env, jobject o, jobject method))
257 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
258 MutexLockerEx mu(Compile_lock);
259 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
260 return mh->queued_for_compilation();
261 WB_END
262
263 WB_ENTRY(jint, WB_GetMethodCompilationLevel(JNIEnv* env, jobject o, jobject method, jboolean is_osr))
264 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
265 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
266 nmethod* code = is_osr ? mh->lookup_osr_nmethod_for(InvocationEntryBci, CompLevel_none, false) : mh->code();
267 return (code != NULL ? code->comp_level() : CompLevel_none);
268 WB_END
269
270 WB_ENTRY(void, WB_MakeMethodNotCompilable(JNIEnv* env, jobject o, jobject method, jint comp_level, jboolean is_osr))
271 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
272 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
273 if (is_osr) {
274 mh->set_not_osr_compilable(comp_level, true /* report */, "WhiteBox");
275 } else {
276 mh->set_not_compilable(comp_level, true /* report */, "WhiteBox");
277 }
278 WB_END
279
280 WB_ENTRY(jint, WB_GetMethodEntryBci(JNIEnv* env, jobject o, jobject method))
281 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
282 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
283 nmethod* code = mh->lookup_osr_nmethod_for(InvocationEntryBci, CompLevel_none, false);
284 return (code != NULL && code->is_osr_method() ? code->osr_entry_bci() : InvocationEntryBci);
285 WB_END
286
287 WB_ENTRY(jboolean, WB_TestSetDontInlineMethod(JNIEnv* env, jobject o, jobject method, jboolean value))
288 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
289 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
290 bool result = mh->dont_inline();
291 mh->set_dont_inline(value == JNI_TRUE);
292 return result;
293 WB_END
294
295 WB_ENTRY(jint, WB_GetCompileQueueSize(JNIEnv* env, jobject o, jint comp_level))
296 if (comp_level == CompLevel_any) {
297 return CompileBroker::queue_size(CompLevel_full_optimization) /* C2 */ +
298 CompileBroker::queue_size(CompLevel_full_profile) /* C1 */;
299 } else {
300 return CompileBroker::queue_size(comp_level);
301 }
302 WB_END
303
304 WB_ENTRY(jboolean, WB_TestSetForceInlineMethod(JNIEnv* env, jobject o, jobject method, jboolean value))
305 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
306 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
307 bool result = mh->force_inline();
308 mh->set_force_inline(value == JNI_TRUE);
309 return result;
310 WB_END
311
312 WB_ENTRY(jboolean, WB_EnqueueMethodForCompilation(JNIEnv* env, jobject o, jobject method, jint comp_level, jint bci))
313 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
314 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
315 nmethod* nm = CompileBroker::compile_method(mh, bci, comp_level, mh, mh->invocation_count(), "WhiteBox", THREAD);
316 MutexLockerEx mu(Compile_lock);
317 return (mh->queued_for_compilation() || nm != NULL);
318 WB_END
319
320 WB_ENTRY(void, WB_ClearMethodState(JNIEnv* env, jobject o, jobject method))
321 jmethodID jmid = reflected_method_to_jmid(thread, env, method);
322 methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
323 MutexLockerEx mu(Compile_lock);
324 MethodData* mdo = mh->method_data();
325 MethodCounters* mcs = mh->method_counters();
326
327 if (mdo != NULL) {
328 mdo->init();
329 ResourceMark rm;
330 int arg_count = mdo->method()->size_of_parameters();
331 for (int i = 0; i < arg_count; i++) {
332 mdo->set_arg_modified(i, 0);
333 }
334 }
335
336 mh->clear_not_c1_compilable();
337 mh->clear_not_c2_compilable();
338 mh->clear_not_c2_osr_compilable();
339 NOT_PRODUCT(mh->set_compiled_invocation_count(0));
340 if (mcs != NULL) {
341 mcs->backedge_counter()->init();
342 mcs->invocation_counter()->init();
343 mcs->set_interpreter_invocation_count(0);
344 mcs->set_interpreter_throwout_count(0);
345
346 #ifdef TIERED
347 mcs->set_rate(0.0F);
348 mh->set_prev_event_count(0, THREAD);
349 mh->set_prev_time(0, THREAD);
350 #endif
351 }
352 WB_END
353
354 WB_ENTRY(jboolean, WB_IsInStringTable(JNIEnv* env, jobject o, jstring javaString))
355 ResourceMark rm(THREAD);
356 int len;
357 jchar* name = java_lang_String::as_unicode_string(JNIHandles::resolve(javaString), len, CHECK_false);
358 return (StringTable::lookup(name, len) != NULL);
359 WB_END
360
361 WB_ENTRY(void, WB_FullGC(JNIEnv* env, jobject o))
362 Universe::heap()->collector_policy()->set_should_clear_all_soft_refs(true);
363 Universe::heap()->collect(GCCause::_last_ditch_collection);
364 WB_END
365
366
367 WB_ENTRY(void, WB_ReadReservedMemory(JNIEnv* env, jobject o))
368 // static+volatile in order to force the read to happen
369 // (not be eliminated by the compiler)
370 static char c;
371 static volatile char* p;
372
373 p = os::reserve_memory(os::vm_allocation_granularity(), NULL, 0);
374 if (p == NULL) {
375 THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), "Failed to reserve memory");
376 }
377
378 c = *p;
379 WB_END
380
381 //Some convenience methods to deal with objects from java
382 int WhiteBox::offset_for_field(const char* field_name, oop object,
383 Symbol* signature_symbol) {
384 assert(field_name != NULL && strlen(field_name) > 0, "Field name not valid");
385 Thread* THREAD = Thread::current();
386
387 //Get the class of our object
388 Klass* arg_klass = object->klass();
389 //Turn it into an instance-klass
390 InstanceKlass* ik = InstanceKlass::cast(arg_klass);
391
392 //Create symbols to look for in the class
393 TempNewSymbol name_symbol = SymbolTable::lookup(field_name, (int) strlen(field_name),
394 THREAD);
395
396 //To be filled in with an offset of the field we're looking for
397 fieldDescriptor fd;
398
399 Klass* res = ik->find_field(name_symbol, signature_symbol, &fd);
400 if (res == NULL) {
401 tty->print_cr("Invalid layout of %s at %s", ik->external_name(),
402 name_symbol->as_C_string());
403 fatal("Invalid layout of preloaded class");
404 }
405
406 //fetch the field at the offset we've found
407 int dest_offset = fd.offset();
408
409 return dest_offset;
410 }
411
412
413 const char* WhiteBox::lookup_jstring(const char* field_name, oop object) {
414 int offset = offset_for_field(field_name, object,
415 vmSymbols::string_signature());
416 oop string = object->obj_field(offset);
417 if (string == NULL) {
418 return NULL;
419 }
420 const char* ret = java_lang_String::as_utf8_string(string);
421 return ret;
422 }
423
424 bool WhiteBox::lookup_bool(const char* field_name, oop object) {
425 int offset =
426 offset_for_field(field_name, object, vmSymbols::bool_signature());
427 bool ret = (object->bool_field(offset) == JNI_TRUE);
428 return ret;
429 }
430
431
432 #define CC (char*)
433
434 static JNINativeMethod methods[] = {
435 {CC"getObjectAddress", CC"(Ljava/lang/Object;)J", (void*)&WB_GetObjectAddress },
436 {CC"getHeapOopSize", CC"()I", (void*)&WB_GetHeapOopSize },
437 {CC"isClassAlive0", CC"(Ljava/lang/String;)Z", (void*)&WB_IsClassAlive },
438 {CC"parseCommandLine",
439 CC"(Ljava/lang/String;[Lsun/hotspot/parser/DiagnosticCommand;)[Ljava/lang/Object;",
440 (void*) &WB_ParseCommandLine
441 },
442 {CC"printCompressedOopsHeapInfo",
443 CC"()V",
444 (void*)&WB_PrintCompressedOopsHeapInfo},
445 {CC"printHeapSizes", CC"()V", (void*)&WB_PrintHeapSizes },
446 #if INCLUDE_ALL_GCS
447 {CC"g1InConcurrentMark", CC"()Z", (void*)&WB_G1InConcurrentMark},
448 {CC"g1IsHumongous", CC"(Ljava/lang/Object;)Z", (void*)&WB_G1IsHumongous },
449 {CC"g1NumFreeRegions", CC"()J", (void*)&WB_G1NumFreeRegions },
450 {CC"g1RegionSize", CC"()I", (void*)&WB_G1RegionSize },
451 #endif // INCLUDE_ALL_GCS
452 #ifdef INCLUDE_NMT
453 {CC"NMTMalloc", CC"(J)J", (void*)&WB_NMTMalloc },
454 {CC"NMTFree", CC"(J)V", (void*)&WB_NMTFree },
455 {CC"NMTReserveMemory", CC"(J)J", (void*)&WB_NMTReserveMemory },
456 {CC"NMTCommitMemory", CC"(JJ)V", (void*)&WB_NMTCommitMemory },
457 {CC"NMTUncommitMemory", CC"(JJ)V", (void*)&WB_NMTUncommitMemory },
458 {CC"NMTReleaseMemory", CC"(JJ)V", (void*)&WB_NMTReleaseMemory },
459 {CC"NMTWaitForDataMerge", CC"()Z", (void*)&WB_NMTWaitForDataMerge},
460 #endif // INCLUDE_NMT
461 {CC"deoptimizeAll", CC"()V", (void*)&WB_DeoptimizeAll },
462 {CC"deoptimizeMethod", CC"(Ljava/lang/reflect/Executable;Z)I",
463 (void*)&WB_DeoptimizeMethod },
464 {CC"isMethodCompiled", CC"(Ljava/lang/reflect/Executable;Z)Z",
465 (void*)&WB_IsMethodCompiled },
466 {CC"isMethodCompilable", CC"(Ljava/lang/reflect/Executable;IZ)Z",
467 (void*)&WB_IsMethodCompilable},
468 {CC"isMethodQueuedForCompilation",
469 CC"(Ljava/lang/reflect/Executable;)Z", (void*)&WB_IsMethodQueuedForCompilation},
470 {CC"makeMethodNotCompilable",
471 CC"(Ljava/lang/reflect/Executable;IZ)V", (void*)&WB_MakeMethodNotCompilable},
472 {CC"testSetDontInlineMethod",
473 CC"(Ljava/lang/reflect/Executable;Z)Z", (void*)&WB_TestSetDontInlineMethod},
474 {CC"getMethodCompilationLevel",
475 CC"(Ljava/lang/reflect/Executable;Z)I", (void*)&WB_GetMethodCompilationLevel},
476 {CC"getMethodEntryBci",
477 CC"(Ljava/lang/reflect/Executable;)I", (void*)&WB_GetMethodEntryBci},
478 {CC"getCompileQueueSize",
479 CC"(I)I", (void*)&WB_GetCompileQueueSize},
480 {CC"testSetForceInlineMethod",
481 CC"(Ljava/lang/reflect/Executable;Z)Z", (void*)&WB_TestSetForceInlineMethod},
482 {CC"enqueueMethodForCompilation",
483 CC"(Ljava/lang/reflect/Executable;II)Z", (void*)&WB_EnqueueMethodForCompilation},
484 {CC"clearMethodState",
485 CC"(Ljava/lang/reflect/Executable;)V", (void*)&WB_ClearMethodState},
486 {CC"isInStringTable", CC"(Ljava/lang/String;)Z", (void*)&WB_IsInStringTable },
487 {CC"fullGC", CC"()V", (void*)&WB_FullGC },
488 {CC"readReservedMemory", CC"()V", (void*)&WB_ReadReservedMemory },
489 };
490
491 #undef CC
492
493 JVM_ENTRY(void, JVM_RegisterWhiteBoxMethods(JNIEnv* env, jclass wbclass))
494 {
495 if (WhiteBoxAPI) {
496 // Make sure that wbclass is loaded by the null classloader
497 instanceKlassHandle ikh = instanceKlassHandle(JNIHandles::resolve(wbclass)->klass());
498 Handle loader(ikh->class_loader());
499 if (loader.is_null()) {
500 ResourceMark rm;
501 ThreadToNativeFromVM ttnfv(thread); // can't be in VM when we call JNI
502 bool result = true;
503 // one by one registration natives for exception catching
504 jclass exceptionKlass = env->FindClass(vmSymbols::java_lang_NoSuchMethodError()->as_C_string());
505 for (int i = 0, n = sizeof(methods) / sizeof(methods[0]); i < n; ++i) {
506 if (env->RegisterNatives(wbclass, methods + i, 1) != 0) {
507 result = false;
508 if (env->ExceptionCheck() && env->IsInstanceOf(env->ExceptionOccurred(), exceptionKlass)) {
509 // j.l.NoSuchMethodError is thrown when a method can't be found or a method is not native
510 // ignoring the exception
511 tty->print_cr("Warning: 'NoSuchMethodError' on register of sun.hotspot.WhiteBox::%s%s", methods[i].name, methods[i].signature);
512 env->ExceptionClear();
513 } else {
514 // register is failed w/o exception or w/ unexpected exception
515 tty->print_cr("Warning: unexpected error on register of sun.hotspot.WhiteBox::%s%s. All methods will be unregistered", methods[i].name, methods[i].signature);
516 env->UnregisterNatives(wbclass);
517 break;
518 }
519 }
520 }
521
522 if (result) {
523 WhiteBox::set_used();
524 }
525 }
526 }
527 }
528 JVM_END