1 /*
   2  * Copyright (c) 2012, 2014, 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 #define SIZE_T_MAX_VALUE ((size_t) -1)
  57 
  58 bool WhiteBox::_used = false;
  59 
  60 WB_ENTRY(jlong, WB_GetObjectAddress(JNIEnv* env, jobject o, jobject obj))
  61   return (jlong)(void*)JNIHandles::resolve(obj);
  62 WB_END
  63 
  64 WB_ENTRY(jint, WB_GetHeapOopSize(JNIEnv* env, jobject o))
  65   return heapOopSize;
  66 WB_END
  67 
  68 
  69 class WBIsKlassAliveClosure : public KlassClosure {
  70     Symbol* _name;
  71     bool _found;
  72 public:
  73     WBIsKlassAliveClosure(Symbol* name) : _name(name), _found(false) {}
  74 
  75     void do_klass(Klass* k) {
  76       if (_found) return;
  77       Symbol* ksym = k->name();
  78       if (ksym->fast_compare(_name) == 0) {
  79         _found = true;
  80       }
  81     }
  82 
  83     bool found() const {
  84         return _found;
  85     }
  86 };
  87 
  88 WB_ENTRY(jboolean, WB_IsClassAlive(JNIEnv* env, jobject target, jstring name))
  89   Handle h_name = JNIHandles::resolve(name);
  90   if (h_name.is_null()) return false;
  91   Symbol* sym = java_lang_String::as_symbol(h_name, CHECK_false);
  92   TempNewSymbol tsym(sym); // Make sure to decrement reference count on sym on return
  93 
  94   WBIsKlassAliveClosure closure(sym);
  95   ClassLoaderDataGraph::classes_do(&closure);
  96 
  97   return closure.found();
  98 WB_END
  99 
 100 WB_ENTRY(jlong, WB_GetCompressedOopsMaxHeapSize(JNIEnv* env, jobject o)) {
 101   return (jlong)Arguments::max_heap_for_compressed_oops();
 102 }
 103 WB_END
 104 
 105 WB_ENTRY(void, WB_PrintHeapSizes(JNIEnv* env, jobject o)) {
 106   CollectorPolicy * p = Universe::heap()->collector_policy();
 107   gclog_or_tty->print_cr("Minimum heap "SIZE_FORMAT" Initial heap "
 108     SIZE_FORMAT" Maximum heap "SIZE_FORMAT" Space alignment "SIZE_FORMAT" Heap alignment "SIZE_FORMAT,
 109     p->min_heap_byte_size(), p->initial_heap_byte_size(), p->max_heap_byte_size(),
 110     p->space_alignment(), p->heap_alignment());
 111 }
 112 WB_END
 113 
 114 #ifndef PRODUCT
 115 // Forward declaration
 116 void TestReservedSpace_test();
 117 void TestReserveMemorySpecial_test();
 118 void TestVirtualSpace_test();
 119 void TestMetaspaceAux_test();
 120 #endif
 121 
 122 WB_ENTRY(void, WB_RunMemoryUnitTests(JNIEnv* env, jobject o))
 123 #ifndef PRODUCT
 124   TestReservedSpace_test();
 125   TestReserveMemorySpecial_test();
 126   TestVirtualSpace_test();
 127   TestMetaspaceAux_test();
 128 #endif
 129 WB_END
 130 
 131 WB_ENTRY(void, WB_ReadFromNoaccessArea(JNIEnv* env, jobject o))
 132   size_t granularity = os::vm_allocation_granularity();
 133   ReservedHeapSpace rhs(100 * granularity, granularity, false, NULL);
 134   VirtualSpace vs;
 135   vs.initialize(rhs, 50 * granularity);
 136 
 137   //Check if constraints are complied
 138   if (!( UseCompressedOops && rhs.base() != NULL &&
 139          Universe::narrow_oop_base() != NULL &&
 140          Universe::narrow_oop_use_implicit_null_checks() )) {
 141     tty->print_cr("WB_ReadFromNoaccessArea method is useless:\n "
 142                   "\tUseCompressedOops is %d\n"
 143                   "\trhs.base() is "PTR_FORMAT"\n"
 144                   "\tUniverse::narrow_oop_base() is "PTR_FORMAT"\n"
 145                   "\tUniverse::narrow_oop_use_implicit_null_checks() is %d",
 146                   UseCompressedOops,
 147                   rhs.base(),
 148                   Universe::narrow_oop_base(),
 149                   Universe::narrow_oop_use_implicit_null_checks());
 150     return;
 151   }
 152   tty->print_cr("Reading from no access area... ");
 153   tty->print_cr("*(vs.low_boundary() - rhs.noaccess_prefix() / 2 ) = %c",
 154                 *(vs.low_boundary() - rhs.noaccess_prefix() / 2 ));
 155 WB_END
 156 
 157 static jint wb_stress_virtual_space_resize(size_t reserved_space_size,
 158                                            size_t magnitude, size_t iterations) {
 159   size_t granularity = os::vm_allocation_granularity();
 160   ReservedHeapSpace rhs(reserved_space_size * granularity, granularity, false, NULL);
 161   VirtualSpace vs;
 162   if (!vs.initialize(rhs, 0)) {
 163     tty->print_cr("Failed to initialize VirtualSpace. Can't proceed.");
 164     return 3;
 165   }
 166 
 167   long seed = os::random();
 168   tty->print_cr("Random seed is %ld", seed);
 169   os::init_random(seed);
 170 
 171   for (size_t i = 0; i < iterations; i++) {
 172 
 173     // Whether we will shrink or grow
 174     bool shrink = os::random() % 2L == 0;
 175 
 176     // Get random delta to resize virtual space
 177     size_t delta = (size_t)os::random() % magnitude;
 178 
 179     // If we are about to shrink virtual space below zero, then expand instead
 180     if (shrink && vs.committed_size() < delta) {
 181       shrink = false;
 182     }
 183 
 184     // Resizing by delta
 185     if (shrink) {
 186       vs.shrink_by(delta);
 187     } else {
 188       // If expanding fails expand_by will silently return false
 189       vs.expand_by(delta, true);
 190     }
 191   }
 192   return 0;
 193 }
 194 
 195 WB_ENTRY(jint, WB_StressVirtualSpaceResize(JNIEnv* env, jobject o,
 196         jlong reserved_space_size, jlong magnitude, jlong iterations))
 197   tty->print_cr("reservedSpaceSize="JLONG_FORMAT", magnitude="JLONG_FORMAT", "
 198                 "iterations="JLONG_FORMAT"\n", reserved_space_size, magnitude,
 199                 iterations);
 200   if (reserved_space_size < 0 || magnitude < 0 || iterations < 0) {
 201     tty->print_cr("One of variables printed above is negative. Can't proceed.\n");
 202     return 1;
 203   }
 204 
 205   // sizeof(size_t) depends on whether OS is 32bit or 64bit. sizeof(jlong) is
 206   // always 8 byte. That's why we should avoid overflow in case of 32bit platform.
 207   if (sizeof(size_t) < sizeof(jlong)) {
 208     jlong size_t_max_value = (jlong) SIZE_T_MAX_VALUE;
 209     if (reserved_space_size > size_t_max_value || magnitude > size_t_max_value
 210         || iterations > size_t_max_value) {
 211       tty->print_cr("One of variables printed above overflows size_t. Can't proceed.\n");
 212       return 2;
 213     }
 214   }
 215 
 216   return wb_stress_virtual_space_resize((size_t) reserved_space_size,
 217                                         (size_t) magnitude, (size_t) iterations);
 218 WB_END
 219 
 220 #if INCLUDE_ALL_GCS
 221 WB_ENTRY(jboolean, WB_G1IsHumongous(JNIEnv* env, jobject o, jobject obj))
 222   G1CollectedHeap* g1 = G1CollectedHeap::heap();
 223   oop result = JNIHandles::resolve(obj);
 224   const HeapRegion* hr = g1->heap_region_containing(result);
 225   return hr->isHumongous();
 226 WB_END
 227 
 228 WB_ENTRY(jlong, WB_G1NumFreeRegions(JNIEnv* env, jobject o))
 229   G1CollectedHeap* g1 = G1CollectedHeap::heap();
 230   size_t nr = g1->free_regions();
 231   return (jlong)nr;
 232 WB_END
 233 
 234 WB_ENTRY(jboolean, WB_G1InConcurrentMark(JNIEnv* env, jobject o))
 235   G1CollectedHeap* g1 = G1CollectedHeap::heap();
 236   ConcurrentMark* cm = g1->concurrent_mark();
 237   return cm->concurrent_marking_in_progress();
 238 WB_END
 239 
 240 WB_ENTRY(jint, WB_G1RegionSize(JNIEnv* env, jobject o))
 241   return (jint)HeapRegion::GrainBytes;
 242 WB_END
 243 #endif // INCLUDE_ALL_GCS
 244 
 245 #if INCLUDE_NMT
 246 // Alloc memory using the test memory type so that we can use that to see if
 247 // NMT picks it up correctly
 248 WB_ENTRY(jlong, WB_NMTMalloc(JNIEnv* env, jobject o, jlong size))
 249   jlong addr = 0;
 250 
 251   if (MemTracker::is_on() && !MemTracker::shutdown_in_progress()) {
 252     addr = (jlong)(uintptr_t)os::malloc(size, mtTest);
 253   }
 254 
 255   return addr;
 256 WB_END
 257 
 258 // Free the memory allocated by NMTAllocTest
 259 WB_ENTRY(void, WB_NMTFree(JNIEnv* env, jobject o, jlong mem))
 260   os::free((void*)(uintptr_t)mem, mtTest);
 261 WB_END
 262 
 263 WB_ENTRY(jlong, WB_NMTReserveMemory(JNIEnv* env, jobject o, jlong size))
 264   jlong addr = 0;
 265 
 266   if (MemTracker::is_on() && !MemTracker::shutdown_in_progress()) {
 267     addr = (jlong)(uintptr_t)os::reserve_memory(size);
 268     MemTracker::record_virtual_memory_type((address)addr, mtTest);
 269   }
 270 
 271   return addr;
 272 WB_END
 273 
 274 
 275 WB_ENTRY(void, WB_NMTCommitMemory(JNIEnv* env, jobject o, jlong addr, jlong size))
 276   os::commit_memory((char *)(uintptr_t)addr, size, !ExecMem);
 277   MemTracker::record_virtual_memory_type((address)(uintptr_t)addr, mtTest);
 278 WB_END
 279 
 280 WB_ENTRY(void, WB_NMTUncommitMemory(JNIEnv* env, jobject o, jlong addr, jlong size))
 281   os::uncommit_memory((char *)(uintptr_t)addr, size);
 282 WB_END
 283 
 284 WB_ENTRY(void, WB_NMTReleaseMemory(JNIEnv* env, jobject o, jlong addr, jlong size))
 285   os::release_memory((char *)(uintptr_t)addr, size);
 286 WB_END
 287 
 288 // Block until the current generation of NMT data to be merged, used to reliably test the NMT feature
 289 WB_ENTRY(jboolean, WB_NMTWaitForDataMerge(JNIEnv* env))
 290 
 291   if (!MemTracker::is_on() || MemTracker::shutdown_in_progress()) {
 292     return false;
 293   }
 294 
 295   return MemTracker::wbtest_wait_for_data_merge();
 296 WB_END
 297 
 298 WB_ENTRY(jboolean, WB_NMTIsDetailSupported(JNIEnv* env))
 299   return MemTracker::tracking_level() == MemTracker::NMT_detail;
 300 WB_END
 301 
 302 #endif // INCLUDE_NMT
 303 
 304 static jmethodID reflected_method_to_jmid(JavaThread* thread, JNIEnv* env, jobject method) {
 305   assert(method != NULL, "method should not be null");
 306   ThreadToNativeFromVM ttn(thread);
 307   return env->FromReflectedMethod(method);
 308 }
 309 
 310 WB_ENTRY(void, WB_DeoptimizeAll(JNIEnv* env, jobject o))
 311   MutexLockerEx mu(Compile_lock);
 312   CodeCache::mark_all_nmethods_for_deoptimization();
 313   VM_Deoptimize op;
 314   VMThread::execute(&op);
 315 WB_END
 316 
 317 WB_ENTRY(jint, WB_DeoptimizeMethod(JNIEnv* env, jobject o, jobject method, jboolean is_osr))
 318   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 319   int result = 0;
 320   CHECK_JNI_EXCEPTION_(env, result);
 321   MutexLockerEx mu(Compile_lock);
 322   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 323   nmethod* code;
 324   if (is_osr) {
 325     int bci = InvocationEntryBci;
 326     while ((code = mh->lookup_osr_nmethod_for(bci, CompLevel_none, false)) != NULL) {
 327       code->mark_for_deoptimization();
 328       ++result;
 329       bci = code->osr_entry_bci() + 1;
 330     }
 331   } else {
 332     code = mh->code();
 333   }
 334   if (code != NULL) {
 335     code->mark_for_deoptimization();
 336     ++result;
 337   }
 338   result += CodeCache::mark_for_deoptimization(mh());
 339   if (result > 0) {
 340     VM_Deoptimize op;
 341     VMThread::execute(&op);
 342   }
 343   return result;
 344 WB_END
 345 
 346 WB_ENTRY(jboolean, WB_IsMethodCompiled(JNIEnv* env, jobject o, jobject method, jboolean is_osr))
 347   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 348   CHECK_JNI_EXCEPTION_(env, JNI_FALSE);
 349   MutexLockerEx mu(Compile_lock);
 350   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 351   nmethod* code = is_osr ? mh->lookup_osr_nmethod_for(InvocationEntryBci, CompLevel_none, false) : mh->code();
 352   if (code == NULL) {
 353     return JNI_FALSE;
 354   }
 355   return (code->is_alive() && !code->is_marked_for_deoptimization());
 356 WB_END
 357 
 358 WB_ENTRY(jboolean, WB_IsMethodCompilable(JNIEnv* env, jobject o, jobject method, jint comp_level, jboolean is_osr))
 359   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 360   CHECK_JNI_EXCEPTION_(env, JNI_FALSE);
 361   MutexLockerEx mu(Compile_lock);
 362   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 363   if (is_osr) {
 364     return CompilationPolicy::can_be_osr_compiled(mh, comp_level);
 365   } else {
 366     return CompilationPolicy::can_be_compiled(mh, comp_level);
 367   }
 368 WB_END
 369 
 370 WB_ENTRY(jboolean, WB_IsMethodQueuedForCompilation(JNIEnv* env, jobject o, jobject method))
 371   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 372   CHECK_JNI_EXCEPTION_(env, JNI_FALSE);
 373   MutexLockerEx mu(Compile_lock);
 374   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 375   return mh->queued_for_compilation();
 376 WB_END
 377 
 378 WB_ENTRY(jint, WB_GetMethodCompilationLevel(JNIEnv* env, jobject o, jobject method, jboolean is_osr))
 379   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 380   CHECK_JNI_EXCEPTION_(env, CompLevel_none);
 381   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 382   nmethod* code = is_osr ? mh->lookup_osr_nmethod_for(InvocationEntryBci, CompLevel_none, false) : mh->code();
 383   return (code != NULL ? code->comp_level() : CompLevel_none);
 384 WB_END
 385 
 386 WB_ENTRY(void, WB_MakeMethodNotCompilable(JNIEnv* env, jobject o, jobject method, jint comp_level, jboolean is_osr))
 387   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 388   CHECK_JNI_EXCEPTION(env);
 389   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 390   if (is_osr) {
 391     mh->set_not_osr_compilable(comp_level, true /* report */, "WhiteBox");
 392   } else {
 393     mh->set_not_compilable(comp_level, true /* report */, "WhiteBox");
 394   }
 395 WB_END
 396 
 397 WB_ENTRY(jint, WB_GetMethodEntryBci(JNIEnv* env, jobject o, jobject method))
 398   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 399   CHECK_JNI_EXCEPTION_(env, InvocationEntryBci);
 400   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 401   nmethod* code = mh->lookup_osr_nmethod_for(InvocationEntryBci, CompLevel_none, false);
 402   return (code != NULL && code->is_osr_method() ? code->osr_entry_bci() : InvocationEntryBci);
 403 WB_END
 404 
 405 WB_ENTRY(jboolean, WB_TestSetDontInlineMethod(JNIEnv* env, jobject o, jobject method, jboolean value))
 406   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 407   CHECK_JNI_EXCEPTION_(env, JNI_FALSE);
 408   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 409   bool result = mh->dont_inline();
 410   mh->set_dont_inline(value == JNI_TRUE);
 411   return result;
 412 WB_END
 413 
 414 WB_ENTRY(jint, WB_GetCompileQueueSize(JNIEnv* env, jobject o, jint comp_level))
 415   if (comp_level == CompLevel_any) {
 416     return CompileBroker::queue_size(CompLevel_full_optimization) /* C2 */ +
 417         CompileBroker::queue_size(CompLevel_full_profile) /* C1 */;
 418   } else {
 419     return CompileBroker::queue_size(comp_level);
 420   }
 421 WB_END
 422 
 423 WB_ENTRY(jboolean, WB_TestSetForceInlineMethod(JNIEnv* env, jobject o, jobject method, jboolean value))
 424   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 425   CHECK_JNI_EXCEPTION_(env, JNI_FALSE);
 426   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 427   bool result = mh->force_inline();
 428   mh->set_force_inline(value == JNI_TRUE);
 429   return result;
 430 WB_END
 431 
 432 WB_ENTRY(jboolean, WB_EnqueueMethodForCompilation(JNIEnv* env, jobject o, jobject method, jint comp_level, jint bci))
 433   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 434   CHECK_JNI_EXCEPTION_(env, JNI_FALSE);
 435   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 436   nmethod* nm = CompileBroker::compile_method(mh, bci, comp_level, mh, mh->invocation_count(), "WhiteBox", THREAD);
 437   MutexLockerEx mu(Compile_lock);
 438   return (mh->queued_for_compilation() || nm != NULL);
 439 WB_END
 440 
 441 class VM_WhiteBoxOperation : public VM_Operation {
 442  public:
 443   VM_WhiteBoxOperation()                         { }
 444   VMOp_Type type()                  const        { return VMOp_WhiteBoxOperation; }
 445   bool allow_nested_vm_operations() const        { return true; }
 446 };
 447 
 448 class AlwaysFalseClosure : public BoolObjectClosure {
 449  public:
 450   bool do_object_b(oop p) { return false; }
 451 };
 452 
 453 static AlwaysFalseClosure always_false;
 454 
 455 class VM_WhiteBoxCleanMethodData : public VM_WhiteBoxOperation {
 456  public:
 457   VM_WhiteBoxCleanMethodData(MethodData* mdo) : _mdo(mdo) { }
 458   void doit() {
 459     _mdo->clean_method_data(&always_false);
 460   }
 461  private:
 462   MethodData* _mdo;
 463 };
 464 
 465 WB_ENTRY(void, WB_ClearMethodState(JNIEnv* env, jobject o, jobject method))
 466   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 467   CHECK_JNI_EXCEPTION(env);
 468   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 469   MutexLockerEx mu(Compile_lock);
 470   MethodData* mdo = mh->method_data();
 471   MethodCounters* mcs = mh->method_counters();
 472 
 473   if (mdo != NULL) {
 474     mdo->init();
 475     ResourceMark rm;
 476     int arg_count = mdo->method()->size_of_parameters();
 477     for (int i = 0; i < arg_count; i++) {
 478       mdo->set_arg_modified(i, 0);
 479     }
 480     VM_WhiteBoxCleanMethodData op(mdo);
 481     VMThread::execute(&op);
 482   }
 483 
 484   mh->clear_not_c1_compilable();
 485   mh->clear_not_c2_compilable();
 486   mh->clear_not_c2_osr_compilable();
 487   NOT_PRODUCT(mh->set_compiled_invocation_count(0));
 488   if (mcs != NULL) {
 489     mcs->backedge_counter()->init();
 490     mcs->invocation_counter()->init();
 491     mcs->set_interpreter_invocation_count(0);
 492     mcs->set_interpreter_throwout_count(0);
 493 
 494 #ifdef TIERED
 495     mcs->set_rate(0.0F);
 496     mh->set_prev_event_count(0);
 497     mh->set_prev_time(0);
 498 #endif
 499   }
 500 WB_END
 501 
 502 WB_ENTRY(jboolean, WB_IsInStringTable(JNIEnv* env, jobject o, jstring javaString))
 503   ResourceMark rm(THREAD);
 504   int len;
 505   jchar* name = java_lang_String::as_unicode_string(JNIHandles::resolve(javaString), len, CHECK_false);
 506   return (StringTable::lookup(name, len) != NULL);
 507 WB_END
 508 
 509 WB_ENTRY(void, WB_FullGC(JNIEnv* env, jobject o))
 510   Universe::heap()->collector_policy()->set_should_clear_all_soft_refs(true);
 511   Universe::heap()->collect(GCCause::_last_ditch_collection);
 512 WB_END
 513 
 514 
 515 WB_ENTRY(void, WB_ReadReservedMemory(JNIEnv* env, jobject o))
 516   // static+volatile in order to force the read to happen
 517   // (not be eliminated by the compiler)
 518   static char c;
 519   static volatile char* p;
 520 
 521   p = os::reserve_memory(os::vm_allocation_granularity(), NULL, 0);
 522   if (p == NULL) {
 523     THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), "Failed to reserve memory");
 524   }
 525 
 526   c = *p;
 527 WB_END
 528 
 529 WB_ENTRY(jstring, WB_GetCPUFeatures(JNIEnv* env, jobject o))
 530   const char* cpu_features = VM_Version::cpu_features();
 531   ThreadToNativeFromVM ttn(thread);
 532   jstring features_string = env->NewStringUTF(cpu_features);
 533 
 534   CHECK_JNI_EXCEPTION_(env, NULL);
 535 
 536   return features_string;
 537 WB_END
 538 
 539 
 540 WB_ENTRY(jobjectArray, WB_GetNMethod(JNIEnv* env, jobject o, jobject method, jboolean is_osr))
 541   ResourceMark rm(THREAD);
 542   jmethodID jmid = reflected_method_to_jmid(thread, env, method);
 543   CHECK_JNI_EXCEPTION_(env, NULL);
 544   methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
 545   nmethod* code = is_osr ? mh->lookup_osr_nmethod_for(InvocationEntryBci, CompLevel_none, false) : mh->code();
 546   jobjectArray result = NULL;
 547   if (code == NULL) {
 548     return result;
 549   }
 550   int insts_size = code->insts_size();
 551 
 552   ThreadToNativeFromVM ttn(thread);
 553   jclass clazz = env->FindClass(vmSymbols::java_lang_Object()->as_C_string());
 554   CHECK_JNI_EXCEPTION_(env, NULL);
 555   result = env->NewObjectArray(2, clazz, NULL);
 556   if (result == NULL) {
 557     return result;
 558   }
 559 
 560   clazz = env->FindClass(vmSymbols::java_lang_Integer()->as_C_string());
 561   CHECK_JNI_EXCEPTION_(env, NULL);
 562   jmethodID constructor = env->GetMethodID(clazz, vmSymbols::object_initializer_name()->as_C_string(), vmSymbols::int_void_signature()->as_C_string());
 563   CHECK_JNI_EXCEPTION_(env, NULL);
 564   jobject obj = env->NewObject(clazz, constructor, code->comp_level());
 565   CHECK_JNI_EXCEPTION_(env, NULL);
 566   env->SetObjectArrayElement(result, 0, obj);
 567 
 568   jbyteArray insts = env->NewByteArray(insts_size);
 569   CHECK_JNI_EXCEPTION_(env, NULL);
 570   env->SetByteArrayRegion(insts, 0, insts_size, (jbyte*) code->insts_begin());
 571   env->SetObjectArrayElement(result, 1, insts);
 572 
 573   return result;
 574 WB_END
 575 
 576 
 577 //Some convenience methods to deal with objects from java
 578 int WhiteBox::offset_for_field(const char* field_name, oop object,
 579     Symbol* signature_symbol) {
 580   assert(field_name != NULL && strlen(field_name) > 0, "Field name not valid");
 581   Thread* THREAD = Thread::current();
 582 
 583   //Get the class of our object
 584   Klass* arg_klass = object->klass();
 585   //Turn it into an instance-klass
 586   InstanceKlass* ik = InstanceKlass::cast(arg_klass);
 587 
 588   //Create symbols to look for in the class
 589   TempNewSymbol name_symbol = SymbolTable::lookup(field_name, (int) strlen(field_name),
 590       THREAD);
 591 
 592   //To be filled in with an offset of the field we're looking for
 593   fieldDescriptor fd;
 594 
 595   Klass* res = ik->find_field(name_symbol, signature_symbol, &fd);
 596   if (res == NULL) {
 597     tty->print_cr("Invalid layout of %s at %s", ik->external_name(),
 598         name_symbol->as_C_string());
 599     fatal("Invalid layout of preloaded class");
 600   }
 601 
 602   //fetch the field at the offset we've found
 603   int dest_offset = fd.offset();
 604 
 605   return dest_offset;
 606 }
 607 
 608 
 609 const char* WhiteBox::lookup_jstring(const char* field_name, oop object) {
 610   int offset = offset_for_field(field_name, object,
 611       vmSymbols::string_signature());
 612   oop string = object->obj_field(offset);
 613   if (string == NULL) {
 614     return NULL;
 615   }
 616   const char* ret = java_lang_String::as_utf8_string(string);
 617   return ret;
 618 }
 619 
 620 bool WhiteBox::lookup_bool(const char* field_name, oop object) {
 621   int offset =
 622       offset_for_field(field_name, object, vmSymbols::bool_signature());
 623   bool ret = (object->bool_field(offset) == JNI_TRUE);
 624   return ret;
 625 }
 626 
 627 
 628 #define CC (char*)
 629 
 630 static JNINativeMethod methods[] = {
 631   {CC"getObjectAddress",   CC"(Ljava/lang/Object;)J", (void*)&WB_GetObjectAddress  },
 632   {CC"getHeapOopSize",     CC"()I",                   (void*)&WB_GetHeapOopSize    },
 633   {CC"isClassAlive0",      CC"(Ljava/lang/String;)Z", (void*)&WB_IsClassAlive      },
 634   {CC"parseCommandLine",
 635       CC"(Ljava/lang/String;[Lsun/hotspot/parser/DiagnosticCommand;)[Ljava/lang/Object;",
 636       (void*) &WB_ParseCommandLine
 637   },
 638   {CC"getCompressedOopsMaxHeapSize", CC"()J",
 639       (void*)&WB_GetCompressedOopsMaxHeapSize},
 640   {CC"printHeapSizes",     CC"()V",                   (void*)&WB_PrintHeapSizes    },
 641   {CC"runMemoryUnitTests", CC"()V",                   (void*)&WB_RunMemoryUnitTests},
 642   {CC"readFromNoaccessArea",CC"()V",                  (void*)&WB_ReadFromNoaccessArea},
 643   {CC"stressVirtualSpaceResize",CC"(JJJ)I",           (void*)&WB_StressVirtualSpaceResize},
 644 #if INCLUDE_ALL_GCS
 645   {CC"g1InConcurrentMark", CC"()Z",                   (void*)&WB_G1InConcurrentMark},
 646   {CC"g1IsHumongous",      CC"(Ljava/lang/Object;)Z", (void*)&WB_G1IsHumongous     },
 647   {CC"g1NumFreeRegions",   CC"()J",                   (void*)&WB_G1NumFreeRegions  },
 648   {CC"g1RegionSize",       CC"()I",                   (void*)&WB_G1RegionSize      },
 649 #endif // INCLUDE_ALL_GCS
 650 #if INCLUDE_NMT
 651   {CC"NMTMalloc",           CC"(J)J",                 (void*)&WB_NMTMalloc          },
 652   {CC"NMTFree",             CC"(J)V",                 (void*)&WB_NMTFree            },
 653   {CC"NMTReserveMemory",    CC"(J)J",                 (void*)&WB_NMTReserveMemory   },
 654   {CC"NMTCommitMemory",     CC"(JJ)V",                (void*)&WB_NMTCommitMemory    },
 655   {CC"NMTUncommitMemory",   CC"(JJ)V",                (void*)&WB_NMTUncommitMemory  },
 656   {CC"NMTReleaseMemory",    CC"(JJ)V",                (void*)&WB_NMTReleaseMemory   },
 657   {CC"NMTWaitForDataMerge", CC"()Z",                  (void*)&WB_NMTWaitForDataMerge},
 658   {CC"NMTIsDetailSupported",CC"()Z",                  (void*)&WB_NMTIsDetailSupported},
 659 #endif // INCLUDE_NMT
 660   {CC"deoptimizeAll",      CC"()V",                   (void*)&WB_DeoptimizeAll     },
 661   {CC"deoptimizeMethod",   CC"(Ljava/lang/reflect/Executable;Z)I",
 662                                                       (void*)&WB_DeoptimizeMethod  },
 663   {CC"isMethodCompiled",   CC"(Ljava/lang/reflect/Executable;Z)Z",
 664                                                       (void*)&WB_IsMethodCompiled  },
 665   {CC"isMethodCompilable", CC"(Ljava/lang/reflect/Executable;IZ)Z",
 666                                                       (void*)&WB_IsMethodCompilable},
 667   {CC"isMethodQueuedForCompilation",
 668       CC"(Ljava/lang/reflect/Executable;)Z",          (void*)&WB_IsMethodQueuedForCompilation},
 669   {CC"makeMethodNotCompilable",
 670       CC"(Ljava/lang/reflect/Executable;IZ)V",        (void*)&WB_MakeMethodNotCompilable},
 671   {CC"testSetDontInlineMethod",
 672       CC"(Ljava/lang/reflect/Executable;Z)Z",         (void*)&WB_TestSetDontInlineMethod},
 673   {CC"getMethodCompilationLevel",
 674       CC"(Ljava/lang/reflect/Executable;Z)I",         (void*)&WB_GetMethodCompilationLevel},
 675   {CC"getMethodEntryBci",
 676       CC"(Ljava/lang/reflect/Executable;)I",          (void*)&WB_GetMethodEntryBci},
 677   {CC"getCompileQueueSize",
 678       CC"(I)I",                                       (void*)&WB_GetCompileQueueSize},
 679   {CC"testSetForceInlineMethod",
 680       CC"(Ljava/lang/reflect/Executable;Z)Z",         (void*)&WB_TestSetForceInlineMethod},
 681   {CC"enqueueMethodForCompilation",
 682       CC"(Ljava/lang/reflect/Executable;II)Z",        (void*)&WB_EnqueueMethodForCompilation},
 683   {CC"clearMethodState",
 684       CC"(Ljava/lang/reflect/Executable;)V",          (void*)&WB_ClearMethodState},
 685   {CC"isInStringTable",   CC"(Ljava/lang/String;)Z",  (void*)&WB_IsInStringTable  },
 686   {CC"fullGC",   CC"()V",                             (void*)&WB_FullGC },
 687   {CC"readReservedMemory", CC"()V",                   (void*)&WB_ReadReservedMemory },
 688   {CC"getCPUFeatures",     CC"()Ljava/lang/String;",  (void*)&WB_GetCPUFeatures     },
 689   {CC"getNMethod",         CC"(Ljava/lang/reflect/Executable;Z)[Ljava/lang/Object;",
 690                                                       (void*)&WB_GetNMethod         },
 691 };
 692 
 693 #undef CC
 694 
 695 JVM_ENTRY(void, JVM_RegisterWhiteBoxMethods(JNIEnv* env, jclass wbclass))
 696   {
 697     if (WhiteBoxAPI) {
 698       // Make sure that wbclass is loaded by the null classloader
 699       instanceKlassHandle ikh = instanceKlassHandle(JNIHandles::resolve(wbclass)->klass());
 700       Handle loader(ikh->class_loader());
 701       if (loader.is_null()) {
 702         ResourceMark rm;
 703         ThreadToNativeFromVM ttnfv(thread); // can't be in VM when we call JNI
 704         bool result = true;
 705         //  one by one registration natives for exception catching
 706         jclass exceptionKlass = env->FindClass(vmSymbols::java_lang_NoSuchMethodError()->as_C_string());
 707         CHECK_JNI_EXCEPTION(env);
 708         for (int i = 0, n = sizeof(methods) / sizeof(methods[0]); i < n; ++i) {
 709           if (env->RegisterNatives(wbclass, methods + i, 1) != 0) {
 710             result = false;
 711             jthrowable throwable_obj = env->ExceptionOccurred();
 712             if (throwable_obj != NULL) {
 713               env->ExceptionClear();
 714               if (env->IsInstanceOf(throwable_obj, exceptionKlass)) {
 715                 // j.l.NoSuchMethodError is thrown when a method can't be found or a method is not native
 716                 // ignoring the exception
 717                 tty->print_cr("Warning: 'NoSuchMethodError' on register of sun.hotspot.WhiteBox::%s%s", methods[i].name, methods[i].signature);
 718               }
 719             } else {
 720               // register is failed w/o exception or w/ unexpected exception
 721               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);
 722               env->UnregisterNatives(wbclass);
 723               break;
 724             }
 725           }
 726         }
 727 
 728         if (result) {
 729           WhiteBox::set_used();
 730         }
 731       }
 732     }
 733   }
 734 JVM_END