1 /*
   2  * Copyright (c) 1999, 2011, 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/systemDictionary.hpp"
  34 #include "classfile/vmSymbols.hpp"
  35 #include "code/codeBlob.hpp"
  36 #include "code/compiledIC.hpp"
  37 #include "code/pcDesc.hpp"
  38 #include "code/scopeDesc.hpp"
  39 #include "code/vtableStubs.hpp"
  40 #include "compiler/disassembler.hpp"
  41 #include "gc_interface/collectedHeap.hpp"
  42 #include "interpreter/bytecode.hpp"
  43 #include "interpreter/interpreter.hpp"
  44 #include "memory/allocation.inline.hpp"
  45 #include "memory/barrierSet.hpp"
  46 #include "memory/oopFactory.hpp"
  47 #include "memory/resourceArea.hpp"
  48 #include "oops/objArrayKlass.hpp"
  49 #include "oops/oop.inline.hpp"
  50 #include "runtime/biasedLocking.hpp"
  51 #include "runtime/compilationPolicy.hpp"
  52 #include "runtime/interfaceSupport.hpp"
  53 #include "runtime/javaCalls.hpp"
  54 #include "runtime/sharedRuntime.hpp"
  55 #include "runtime/threadCritical.hpp"
  56 #include "runtime/vframe.hpp"
  57 #include "runtime/vframeArray.hpp"
  58 #include "utilities/copy.hpp"
  59 #include "utilities/events.hpp"
  60 
  61 
  62 // Implementation of StubAssembler
  63 
  64 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
  65   _name = name;
  66   _must_gc_arguments = false;
  67   _frame_size = no_frame_size;
  68   _num_rt_args = 0;
  69   _stub_id = stub_id;
  70 }
  71 
  72 
  73 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
  74   _name = name;
  75   _must_gc_arguments = must_gc_arguments;
  76 }
  77 
  78 
  79 void StubAssembler::set_frame_size(int size) {
  80   if (_frame_size == no_frame_size) {
  81     _frame_size = size;
  82   }
  83   assert(_frame_size == size, "can't change the frame size");
  84 }
  85 
  86 
  87 void StubAssembler::set_num_rt_args(int args) {
  88   if (_num_rt_args == 0) {
  89     _num_rt_args = args;
  90   }
  91   assert(_num_rt_args == args, "can't change the number of args");
  92 }
  93 
  94 // Implementation of Runtime1
  95 
  96 CodeBlob* Runtime1::_blobs[Runtime1::number_of_ids];
  97 const char *Runtime1::_blob_names[] = {
  98   RUNTIME1_STUBS(STUB_NAME, LAST_STUB_NAME)
  99 };
 100 
 101 #ifndef PRODUCT
 102 // statistics
 103 int Runtime1::_generic_arraycopy_cnt = 0;
 104 int Runtime1::_primitive_arraycopy_cnt = 0;
 105 int Runtime1::_oop_arraycopy_cnt = 0;
 106 int Runtime1::_generic_arraycopystub_cnt = 0;
 107 int Runtime1::_arraycopy_slowcase_cnt = 0;
 108 int Runtime1::_arraycopy_checkcast_cnt = 0;
 109 int Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
 110 int Runtime1::_new_type_array_slowcase_cnt = 0;
 111 int Runtime1::_new_object_array_slowcase_cnt = 0;
 112 int Runtime1::_new_instance_slowcase_cnt = 0;
 113 int Runtime1::_new_multi_array_slowcase_cnt = 0;
 114 int Runtime1::_monitorenter_slowcase_cnt = 0;
 115 int Runtime1::_monitorexit_slowcase_cnt = 0;
 116 int Runtime1::_patch_code_slowcase_cnt = 0;
 117 int Runtime1::_throw_range_check_exception_count = 0;
 118 int Runtime1::_throw_index_exception_count = 0;
 119 int Runtime1::_throw_div0_exception_count = 0;
 120 int Runtime1::_throw_null_pointer_exception_count = 0;
 121 int Runtime1::_throw_class_cast_exception_count = 0;
 122 int Runtime1::_throw_incompatible_class_change_error_count = 0;
 123 int Runtime1::_throw_array_store_exception_count = 0;
 124 int Runtime1::_throw_count = 0;
 125 
 126 static int _byte_arraycopy_cnt = 0;
 127 static int _short_arraycopy_cnt = 0;
 128 static int _int_arraycopy_cnt = 0;
 129 static int _long_arraycopy_cnt = 0;
 130 static int _oop_arraycopy_cnt = 0;
 131 
 132 address Runtime1::arraycopy_count_address(BasicType type) {
 133   switch (type) {
 134   case T_BOOLEAN:
 135   case T_BYTE:   return (address)&_byte_arraycopy_cnt;
 136   case T_CHAR:
 137   case T_SHORT:  return (address)&_short_arraycopy_cnt;
 138   case T_FLOAT:
 139   case T_INT:    return (address)&_int_arraycopy_cnt;
 140   case T_DOUBLE:
 141   case T_LONG:   return (address)&_long_arraycopy_cnt;
 142   case T_ARRAY:
 143   case T_OBJECT: return (address)&_oop_arraycopy_cnt;
 144   default:
 145     ShouldNotReachHere();
 146     return NULL;
 147   }
 148 }
 149 
 150 
 151 #endif
 152 
 153 // Simple helper to see if the caller of a runtime stub which
 154 // entered the VM has been deoptimized
 155 
 156 static bool caller_is_deopted() {
 157   JavaThread* thread = JavaThread::current();
 158   RegisterMap reg_map(thread, false);
 159   frame runtime_frame = thread->last_frame();
 160   frame caller_frame = runtime_frame.sender(&reg_map);
 161   assert(caller_frame.is_compiled_frame(), "must be compiled");
 162   return caller_frame.is_deoptimized_frame();
 163 }
 164 
 165 // Stress deoptimization
 166 static void deopt_caller() {
 167   if ( !caller_is_deopted()) {
 168     JavaThread* thread = JavaThread::current();
 169     RegisterMap reg_map(thread, false);
 170     frame runtime_frame = thread->last_frame();
 171     frame caller_frame = runtime_frame.sender(&reg_map);
 172     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 173     assert(caller_is_deopted(), "Must be deoptimized");
 174   }
 175 }
 176 
 177 
 178 void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
 179   assert(0 <= id && id < number_of_ids, "illegal stub id");
 180   ResourceMark rm;
 181   // create code buffer for code storage
 182   CodeBuffer code(buffer_blob);
 183 
 184   Compilation::setup_code_buffer(&code, 0);
 185 
 186   // create assembler for code generation
 187   StubAssembler* sasm = new StubAssembler(&code, name_for(id), id);
 188   // generate code for runtime stub
 189   OopMapSet* oop_maps;
 190   oop_maps = generate_code_for(id, sasm);
 191   assert(oop_maps == NULL || sasm->frame_size() != no_frame_size,
 192          "if stub has an oop map it must have a valid frame size");
 193 
 194 #ifdef ASSERT
 195   // Make sure that stubs that need oopmaps have them
 196   switch (id) {
 197     // These stubs don't need to have an oopmap
 198     case dtrace_object_alloc_id:
 199     case g1_pre_barrier_slow_id:
 200     case g1_post_barrier_slow_id:
 201     case slow_subtype_check_id:
 202     case fpu2long_stub_id:
 203     case unwind_exception_id:
 204     case counter_overflow_id:
 205 #if defined(SPARC) || defined(PPC)
 206     case handle_exception_nofpu_id:  // Unused on sparc
 207 #endif
 208       break;
 209 
 210     // All other stubs should have oopmaps
 211     default:
 212       assert(oop_maps != NULL, "must have an oopmap");
 213   }
 214 #endif
 215 
 216   // align so printing shows nop's instead of random code at the end (SimpleStubs are aligned)
 217   sasm->align(BytesPerWord);
 218   // make sure all code is in code buffer
 219   sasm->flush();
 220   // create blob - distinguish a few special cases
 221   CodeBlob* blob = RuntimeStub::new_runtime_stub(name_for(id),
 222                                                  &code,
 223                                                  CodeOffsets::frame_never_safe,
 224                                                  sasm->frame_size(),
 225                                                  oop_maps,
 226                                                  sasm->must_gc_arguments());
 227   // install blob
 228   assert(blob != NULL, "blob must exist");
 229   _blobs[id] = blob;
 230 }
 231 
 232 
 233 void Runtime1::initialize(BufferBlob* blob) {
 234   // platform-dependent initialization
 235   initialize_pd();
 236   // generate stubs
 237   for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
 238   // printing
 239 #ifndef PRODUCT
 240   if (PrintSimpleStubs) {
 241     ResourceMark rm;
 242     for (int id = 0; id < number_of_ids; id++) {
 243       _blobs[id]->print();
 244       if (_blobs[id]->oop_maps() != NULL) {
 245         _blobs[id]->oop_maps()->print();
 246       }
 247     }
 248   }
 249 #endif
 250 }
 251 
 252 
 253 CodeBlob* Runtime1::blob_for(StubID id) {
 254   assert(0 <= id && id < number_of_ids, "illegal stub id");
 255   return _blobs[id];
 256 }
 257 
 258 
 259 const char* Runtime1::name_for(StubID id) {
 260   assert(0 <= id && id < number_of_ids, "illegal stub id");
 261   return _blob_names[id];
 262 }
 263 
 264 const char* Runtime1::name_for_address(address entry) {
 265   for (int id = 0; id < number_of_ids; id++) {
 266     if (entry == entry_for((StubID)id)) return name_for((StubID)id);
 267   }
 268 
 269 #define FUNCTION_CASE(a, f) \
 270   if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f))  return #f
 271 
 272   FUNCTION_CASE(entry, os::javaTimeMillis);
 273   FUNCTION_CASE(entry, os::javaTimeNanos);
 274   FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
 275   FUNCTION_CASE(entry, SharedRuntime::d2f);
 276   FUNCTION_CASE(entry, SharedRuntime::d2i);
 277   FUNCTION_CASE(entry, SharedRuntime::d2l);
 278   FUNCTION_CASE(entry, SharedRuntime::dcos);
 279   FUNCTION_CASE(entry, SharedRuntime::dexp);
 280   FUNCTION_CASE(entry, SharedRuntime::dlog);
 281   FUNCTION_CASE(entry, SharedRuntime::dlog10);
 282   FUNCTION_CASE(entry, SharedRuntime::dpow);
 283   FUNCTION_CASE(entry, SharedRuntime::drem);
 284   FUNCTION_CASE(entry, SharedRuntime::dsin);
 285   FUNCTION_CASE(entry, SharedRuntime::dtan);
 286   FUNCTION_CASE(entry, SharedRuntime::f2i);
 287   FUNCTION_CASE(entry, SharedRuntime::f2l);
 288   FUNCTION_CASE(entry, SharedRuntime::frem);
 289   FUNCTION_CASE(entry, SharedRuntime::l2d);
 290   FUNCTION_CASE(entry, SharedRuntime::l2f);
 291   FUNCTION_CASE(entry, SharedRuntime::ldiv);
 292   FUNCTION_CASE(entry, SharedRuntime::lmul);
 293   FUNCTION_CASE(entry, SharedRuntime::lrem);
 294   FUNCTION_CASE(entry, SharedRuntime::lrem);
 295   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
 296   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
 297   FUNCTION_CASE(entry, trace_block_entry);
 298 
 299 #undef FUNCTION_CASE
 300 
 301   // Soft float adds more runtime names.
 302   return pd_name_for_address(entry);
 303 }
 304 
 305 
 306 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* thread, klassOopDesc* klass))
 307   NOT_PRODUCT(_new_instance_slowcase_cnt++;)
 308 
 309   assert(oop(klass)->is_klass(), "not a class");
 310   instanceKlassHandle h(thread, klass);
 311   h->check_valid_for_instantiation(true, CHECK);
 312   // make sure klass is initialized
 313   h->initialize(CHECK);
 314   // allocate instance and return via TLS
 315   oop obj = h->allocate_instance(CHECK);
 316   thread->set_vm_result(obj);
 317 JRT_END
 318 
 319 
 320 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* thread, klassOopDesc* klass, jint length))
 321   NOT_PRODUCT(_new_type_array_slowcase_cnt++;)
 322   // Note: no handle for klass needed since they are not used
 323   //       anymore after new_typeArray() and no GC can happen before.
 324   //       (This may have to change if this code changes!)
 325   assert(oop(klass)->is_klass(), "not a class");
 326   BasicType elt_type = typeArrayKlass::cast(klass)->element_type();
 327   oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
 328   thread->set_vm_result(obj);
 329   // This is pretty rare but this runtime patch is stressful to deoptimization
 330   // if we deoptimize here so force a deopt to stress the path.
 331   if (DeoptimizeALot) {
 332     deopt_caller();
 333   }
 334 
 335 JRT_END
 336 
 337 
 338 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* thread, klassOopDesc* array_klass, jint length))
 339   NOT_PRODUCT(_new_object_array_slowcase_cnt++;)
 340 
 341   // Note: no handle for klass needed since they are not used
 342   //       anymore after new_objArray() and no GC can happen before.
 343   //       (This may have to change if this code changes!)
 344   assert(oop(array_klass)->is_klass(), "not a class");
 345   klassOop elem_klass = objArrayKlass::cast(array_klass)->element_klass();
 346   objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
 347   thread->set_vm_result(obj);
 348   // This is pretty rare but this runtime patch is stressful to deoptimization
 349   // if we deoptimize here so force a deopt to stress the path.
 350   if (DeoptimizeALot) {
 351     deopt_caller();
 352   }
 353 JRT_END
 354 
 355 
 356 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* thread, klassOopDesc* klass, int rank, jint* dims))
 357   NOT_PRODUCT(_new_multi_array_slowcase_cnt++;)
 358 
 359   assert(oop(klass)->is_klass(), "not a class");
 360   assert(rank >= 1, "rank must be nonzero");
 361   oop obj = arrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
 362   thread->set_vm_result(obj);
 363 JRT_END
 364 
 365 
 366 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* thread, StubID id))
 367   tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
 368 JRT_END
 369 
 370 
 371 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* thread, oopDesc* obj))
 372   ResourceMark rm(thread);
 373   const char* klass_name = Klass::cast(obj->klass())->external_name();
 374   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayStoreException(), klass_name);
 375 JRT_END
 376 
 377 
 378 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
 379 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
 380 // method) method oop is passed as an argument. In order to do that it is embedded in the code as
 381 // a constant.
 382 static nmethod* counter_overflow_helper(JavaThread* THREAD, int branch_bci, methodOopDesc* m) {
 383   nmethod* osr_nm = NULL;
 384   methodHandle method(THREAD, m);
 385 
 386   RegisterMap map(THREAD, false);
 387   frame fr =  THREAD->last_frame().sender(&map);
 388   nmethod* nm = (nmethod*) fr.cb();
 389   assert(nm!= NULL && nm->is_nmethod(), "Sanity check");
 390   methodHandle enclosing_method(THREAD, nm->method());
 391 
 392   CompLevel level = (CompLevel)nm->comp_level();
 393   int bci = InvocationEntryBci;
 394   if (branch_bci != InvocationEntryBci) {
 395     // Compute desination bci
 396     address pc = method()->code_base() + branch_bci;
 397     Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
 398     int offset = 0;
 399     switch (branch) {
 400       case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
 401       case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
 402       case Bytecodes::_if_icmple: case Bytecodes::_ifle:
 403       case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
 404       case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
 405       case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
 406       case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
 407         offset = (int16_t)Bytes::get_Java_u2(pc + 1);
 408         break;
 409       case Bytecodes::_goto_w:
 410         offset = Bytes::get_Java_u4(pc + 1);
 411         break;
 412       default: ;
 413     }
 414     bci = branch_bci + offset;
 415   }
 416 
 417   osr_nm = CompilationPolicy::policy()->event(enclosing_method, method, branch_bci, bci, level, nm, THREAD);
 418   return osr_nm;
 419 }
 420 
 421 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* thread, int bci, methodOopDesc* method))
 422   nmethod* osr_nm;
 423   JRT_BLOCK
 424     osr_nm = counter_overflow_helper(thread, bci, method);
 425     if (osr_nm != NULL) {
 426       RegisterMap map(thread, false);
 427       frame fr =  thread->last_frame().sender(&map);
 428       Deoptimization::deoptimize_frame(thread, fr.id());
 429     }
 430   JRT_BLOCK_END
 431   return NULL;
 432 JRT_END
 433 
 434 extern void vm_exit(int code);
 435 
 436 // Enter this method from compiled code handler below. This is where we transition
 437 // to VM mode. This is done as a helper routine so that the method called directly
 438 // from compiled code does not have to transition to VM. This allows the entry
 439 // method to see if the nmethod that we have just looked up a handler for has
 440 // been deoptimized while we were in the vm. This simplifies the assembly code
 441 // cpu directories.
 442 //
 443 // We are entering here from exception stub (via the entry method below)
 444 // If there is a compiled exception handler in this method, we will continue there;
 445 // otherwise we will unwind the stack and continue at the caller of top frame method
 446 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
 447 // control the area where we can allow a safepoint. After we exit the safepoint area we can
 448 // check to see if the handler we are going to return is now in a nmethod that has
 449 // been deoptimized. If that is the case we return the deopt blob
 450 // unpack_with_exception entry instead. This makes life for the exception blob easier
 451 // because making that same check and diverting is painful from assembly language.
 452 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* thread, oopDesc* ex, address pc, nmethod*& nm))
 453   // Reset method handle flag.
 454   thread->set_is_method_handle_return(false);
 455 
 456   Handle exception(thread, ex);
 457   nm = CodeCache::find_nmethod(pc);
 458   assert(nm != NULL, "this is not an nmethod");
 459   // Adjust the pc as needed/
 460   if (nm->is_deopt_pc(pc)) {
 461     RegisterMap map(thread, false);
 462     frame exception_frame = thread->last_frame().sender(&map);
 463     // if the frame isn't deopted then pc must not correspond to the caller of last_frame
 464     assert(exception_frame.is_deoptimized_frame(), "must be deopted");
 465     pc = exception_frame.pc();
 466   }
 467 #ifdef ASSERT
 468   assert(exception.not_null(), "NULL exceptions should be handled by throw_exception");
 469   assert(exception->is_oop(), "just checking");
 470   // Check that exception is a subclass of Throwable, otherwise we have a VerifyError
 471   if (!(exception->is_a(SystemDictionary::Throwable_klass()))) {
 472     if (ExitVMOnVerifyError) vm_exit(-1);
 473     ShouldNotReachHere();
 474   }
 475 #endif
 476 
 477   // Check the stack guard pages and reenable them if necessary and there is
 478   // enough space on the stack to do so.  Use fast exceptions only if the guard
 479   // pages are enabled.
 480   bool guard_pages_enabled = thread->stack_yellow_zone_enabled();
 481   if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
 482 
 483   if (JvmtiExport::can_post_on_exceptions()) {
 484     // To ensure correct notification of exception catches and throws
 485     // we have to deoptimize here.  If we attempted to notify the
 486     // catches and throws during this exception lookup it's possible
 487     // we could deoptimize on the way out of the VM and end back in
 488     // the interpreter at the throw site.  This would result in double
 489     // notifications since the interpreter would also notify about
 490     // these same catches and throws as it unwound the frame.
 491 
 492     RegisterMap reg_map(thread);
 493     frame stub_frame = thread->last_frame();
 494     frame caller_frame = stub_frame.sender(&reg_map);
 495 
 496     // We don't really want to deoptimize the nmethod itself since we
 497     // can actually continue in the exception handler ourselves but I
 498     // don't see an easy way to have the desired effect.
 499     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 500     assert(caller_is_deopted(), "Must be deoptimized");
 501 
 502     return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 503   }
 504 
 505   // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
 506   if (guard_pages_enabled) {
 507     address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
 508     if (fast_continuation != NULL) {
 509       // Set flag if return address is a method handle call site.
 510       thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 511       return fast_continuation;
 512     }
 513   }
 514 
 515   // If the stack guard pages are enabled, check whether there is a handler in
 516   // the current method.  Otherwise (guard pages disabled), force an unwind and
 517   // skip the exception cache update (i.e., just leave continuation==NULL).
 518   address continuation = NULL;
 519   if (guard_pages_enabled) {
 520 
 521     // New exception handling mechanism can support inlined methods
 522     // with exception handlers since the mappings are from PC to PC
 523 
 524     // debugging support
 525     // tracing
 526     if (TraceExceptions) {
 527       ttyLocker ttyl;
 528       ResourceMark rm;
 529       tty->print_cr("Exception <%s> (0x%x) thrown in compiled method <%s> at PC " PTR_FORMAT " for thread 0x%x",
 530                     exception->print_value_string(), (address)exception(), nm->method()->print_value_string(), pc, thread);
 531     }
 532     // for AbortVMOnException flag
 533     NOT_PRODUCT(Exceptions::debug_check_abort(exception));
 534 
 535     // Clear out the exception oop and pc since looking up an
 536     // exception handler can cause class loading, which might throw an
 537     // exception and those fields are expected to be clear during
 538     // normal bytecode execution.
 539     thread->set_exception_oop(NULL);
 540     thread->set_exception_pc(NULL);
 541 
 542     continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false);
 543     // If an exception was thrown during exception dispatch, the exception oop may have changed
 544     thread->set_exception_oop(exception());
 545     thread->set_exception_pc(pc);
 546 
 547     // the exception cache is used only by non-implicit exceptions
 548     if (continuation != NULL) {
 549       nm->add_handler_for_exception_and_pc(exception, pc, continuation);
 550     }
 551   }
 552 
 553   thread->set_vm_result(exception());
 554   // Set flag if return address is a method handle call site.
 555   thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 556 
 557   if (TraceExceptions) {
 558     ttyLocker ttyl;
 559     ResourceMark rm;
 560     tty->print_cr("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT " for exception thrown at PC " PTR_FORMAT,
 561                   thread, continuation, pc);
 562   }
 563 
 564   return continuation;
 565 JRT_END
 566 
 567 // Enter this method from compiled code only if there is a Java exception handler
 568 // in the method handling the exception.
 569 // We are entering here from exception stub. We don't do a normal VM transition here.
 570 // We do it in a helper. This is so we can check to see if the nmethod we have just
 571 // searched for an exception handler has been deoptimized in the meantime.
 572 address Runtime1::exception_handler_for_pc(JavaThread* thread) {
 573   oop exception = thread->exception_oop();
 574   address pc = thread->exception_pc();
 575   // Still in Java mode
 576   DEBUG_ONLY(ResetNoHandleMark rnhm);
 577   nmethod* nm = NULL;
 578   address continuation = NULL;
 579   {
 580     // Enter VM mode by calling the helper
 581     ResetNoHandleMark rnhm;
 582     continuation = exception_handler_for_pc_helper(thread, exception, pc, nm);
 583   }
 584   // Back in JAVA, use no oops DON'T safepoint
 585 
 586   // Now check to see if the nmethod we were called from is now deoptimized.
 587   // If so we must return to the deopt blob and deoptimize the nmethod
 588   if (nm != NULL && caller_is_deopted()) {
 589     continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 590   }
 591 
 592   assert(continuation != NULL, "no handler found");
 593   return continuation;
 594 }
 595 
 596 
 597 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* thread, int index))
 598   NOT_PRODUCT(_throw_range_check_exception_count++;)
 599   Events::log("throw_range_check");
 600   char message[jintAsStringSize];
 601   sprintf(message, "%d", index);
 602   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
 603 JRT_END
 604 
 605 
 606 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* thread, int index))
 607   NOT_PRODUCT(_throw_index_exception_count++;)
 608   Events::log("throw_index");
 609   char message[16];
 610   sprintf(message, "%d", index);
 611   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
 612 JRT_END
 613 
 614 
 615 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* thread))
 616   NOT_PRODUCT(_throw_div0_exception_count++;)
 617   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
 618 JRT_END
 619 
 620 
 621 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* thread))
 622   NOT_PRODUCT(_throw_null_pointer_exception_count++;)
 623   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_NullPointerException());
 624 JRT_END
 625 
 626 
 627 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* thread, oopDesc* object))
 628   NOT_PRODUCT(_throw_class_cast_exception_count++;)
 629   ResourceMark rm(thread);
 630   char* message = SharedRuntime::generate_class_cast_message(
 631     thread, Klass::cast(object->klass())->external_name());
 632   SharedRuntime::throw_and_post_jvmti_exception(
 633     thread, vmSymbols::java_lang_ClassCastException(), message);
 634 JRT_END
 635 
 636 
 637 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* thread))
 638   NOT_PRODUCT(_throw_incompatible_class_change_error_count++;)
 639   ResourceMark rm(thread);
 640   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IncompatibleClassChangeError());
 641 JRT_END
 642 
 643 
 644 JRT_ENTRY_NO_ASYNC(void, Runtime1::monitorenter(JavaThread* thread, oopDesc* obj, BasicObjectLock* lock))
 645   NOT_PRODUCT(_monitorenter_slowcase_cnt++;)
 646   if (PrintBiasedLockingStatistics) {
 647     Atomic::inc(BiasedLocking::slow_path_entry_count_addr());
 648   }
 649   Handle h_obj(thread, obj);
 650   assert(h_obj()->is_oop(), "must be NULL or an object");
 651   if (UseBiasedLocking) {
 652     // Retry fast entry if bias is revoked to avoid unnecessary inflation
 653     ObjectSynchronizer::fast_enter(h_obj, lock->lock(), true, CHECK);
 654   } else {
 655     if (UseFastLocking) {
 656       // When using fast locking, the compiled code has already tried the fast case
 657       assert(obj == lock->obj(), "must match");
 658       ObjectSynchronizer::slow_enter(h_obj, lock->lock(), THREAD);
 659     } else {
 660       lock->set_obj(obj);
 661       ObjectSynchronizer::fast_enter(h_obj, lock->lock(), false, THREAD);
 662     }
 663   }
 664 JRT_END
 665 
 666 
 667 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* thread, BasicObjectLock* lock))
 668   NOT_PRODUCT(_monitorexit_slowcase_cnt++;)
 669   assert(thread == JavaThread::current(), "threads must correspond");
 670   assert(thread->last_Java_sp(), "last_Java_sp must be set");
 671   // monitorexit is non-blocking (leaf routine) => no exceptions can be thrown
 672   EXCEPTION_MARK;
 673 
 674   oop obj = lock->obj();
 675   assert(obj->is_oop(), "must be NULL or an object");
 676   if (UseFastLocking) {
 677     // When using fast locking, the compiled code has already tried the fast case
 678     ObjectSynchronizer::slow_exit(obj, lock->lock(), THREAD);
 679   } else {
 680     ObjectSynchronizer::fast_exit(obj, lock->lock(), THREAD);
 681   }
 682 JRT_END
 683 
 684 
 685 static klassOop resolve_field_return_klass(methodHandle caller, int bci, TRAPS) {
 686   Bytecode_field field_access(caller, bci);
 687   // This can be static or non-static field access
 688   Bytecodes::Code code       = field_access.code();
 689 
 690   // We must load class, initialize class and resolvethe field
 691   FieldAccessInfo result; // initialize class if needed
 692   constantPoolHandle constants(THREAD, caller->constants());
 693   LinkResolver::resolve_field(result, constants, field_access.index(), Bytecodes::java_code(code), false, CHECK_NULL);
 694   return result.klass()();
 695 }
 696 
 697 
 698 //
 699 // This routine patches sites where a class wasn't loaded or
 700 // initialized at the time the code was generated.  It handles
 701 // references to classes, fields and forcing of initialization.  Most
 702 // of the cases are straightforward and involving simply forcing
 703 // resolution of a class, rewriting the instruction stream with the
 704 // needed constant and replacing the call in this function with the
 705 // patched code.  The case for static field is more complicated since
 706 // the thread which is in the process of initializing a class can
 707 // access it's static fields but other threads can't so the code
 708 // either has to deoptimize when this case is detected or execute a
 709 // check that the current thread is the initializing thread.  The
 710 // current
 711 //
 712 // Patches basically look like this:
 713 //
 714 //
 715 // patch_site: jmp patch stub     ;; will be patched
 716 // continue:   ...
 717 //             ...
 718 //             ...
 719 //             ...
 720 //
 721 // They have a stub which looks like this:
 722 //
 723 //             ;; patch body
 724 //             movl <const>, reg           (for class constants)
 725 //        <or> movl [reg1 + <const>], reg  (for field offsets)
 726 //        <or> movl reg, [reg1 + <const>]  (for field offsets)
 727 //             <being_init offset> <bytes to copy> <bytes to skip>
 728 // patch_stub: call Runtime1::patch_code (through a runtime stub)
 729 //             jmp patch_site
 730 //
 731 //
 732 // A normal patch is done by rewriting the patch body, usually a move,
 733 // and then copying it into place over top of the jmp instruction
 734 // being careful to flush caches and doing it in an MP-safe way.  The
 735 // constants following the patch body are used to find various pieces
 736 // of the patch relative to the call site for Runtime1::patch_code.
 737 // The case for getstatic and putstatic is more complicated because
 738 // getstatic and putstatic have special semantics when executing while
 739 // the class is being initialized.  getstatic/putstatic on a class
 740 // which is being_initialized may be executed by the initializing
 741 // thread but other threads have to block when they execute it.  This
 742 // is accomplished in compiled code by executing a test of the current
 743 // thread against the initializing thread of the class.  It's emitted
 744 // as boilerplate in their stub which allows the patched code to be
 745 // executed before it's copied back into the main body of the nmethod.
 746 //
 747 // being_init: get_thread(<tmp reg>
 748 //             cmpl [reg1 + <init_thread_offset>], <tmp reg>
 749 //             jne patch_stub
 750 //             movl [reg1 + <const>], reg  (for field offsets)  <or>
 751 //             movl reg, [reg1 + <const>]  (for field offsets)
 752 //             jmp continue
 753 //             <being_init offset> <bytes to copy> <bytes to skip>
 754 // patch_stub: jmp Runtim1::patch_code (through a runtime stub)
 755 //             jmp patch_site
 756 //
 757 // If the class is being initialized the patch body is rewritten and
 758 // the patch site is rewritten to jump to being_init, instead of
 759 // patch_stub.  Whenever this code is executed it checks the current
 760 // thread against the intializing thread so other threads will enter
 761 // the runtime and end up blocked waiting the class to finish
 762 // initializing inside the calls to resolve_field below.  The
 763 // initializing class will continue on it's way.  Once the class is
 764 // fully_initialized, the intializing_thread of the class becomes
 765 // NULL, so the next thread to execute this code will fail the test,
 766 // call into patch_code and complete the patching process by copying
 767 // the patch body back into the main part of the nmethod and resume
 768 // executing.
 769 //
 770 //
 771 
 772 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
 773   NOT_PRODUCT(_patch_code_slowcase_cnt++;)
 774 
 775   ResourceMark rm(thread);
 776   RegisterMap reg_map(thread, false);
 777   frame runtime_frame = thread->last_frame();
 778   frame caller_frame = runtime_frame.sender(&reg_map);
 779 
 780   // last java frame on stack
 781   vframeStream vfst(thread, true);
 782   assert(!vfst.at_end(), "Java frame must exist");
 783 
 784   methodHandle caller_method(THREAD, vfst.method());
 785   // Note that caller_method->code() may not be same as caller_code because of OSR's
 786   // Note also that in the presence of inlining it is not guaranteed
 787   // that caller_method() == caller_code->method()
 788 
 789 
 790   int bci = vfst.bci();
 791 
 792   Events::log("patch_code @ " INTPTR_FORMAT , caller_frame.pc());
 793 
 794   Bytecodes::Code code = caller_method()->java_code_at(bci);
 795 
 796 #ifndef PRODUCT
 797   // this is used by assertions in the access_field_patching_id
 798   BasicType patch_field_type = T_ILLEGAL;
 799 #endif // PRODUCT
 800   bool deoptimize_for_volatile = false;
 801   int patch_field_offset = -1;
 802   KlassHandle init_klass(THREAD, klassOop(NULL)); // klass needed by access_field_patching code
 803   Handle load_klass(THREAD, NULL);                // oop needed by load_klass_patching code
 804   if (stub_id == Runtime1::access_field_patching_id) {
 805 
 806     Bytecode_field field_access(caller_method, bci);
 807     FieldAccessInfo result; // initialize class if needed
 808     Bytecodes::Code code = field_access.code();
 809     constantPoolHandle constants(THREAD, caller_method->constants());
 810     LinkResolver::resolve_field(result, constants, field_access.index(), Bytecodes::java_code(code), false, CHECK);
 811     patch_field_offset = result.field_offset();
 812 
 813     // If we're patching a field which is volatile then at compile it
 814     // must not have been know to be volatile, so the generated code
 815     // isn't correct for a volatile reference.  The nmethod has to be
 816     // deoptimized so that the code can be regenerated correctly.
 817     // This check is only needed for access_field_patching since this
 818     // is the path for patching field offsets.  load_klass is only
 819     // used for patching references to oops which don't need special
 820     // handling in the volatile case.
 821     deoptimize_for_volatile = result.access_flags().is_volatile();
 822 
 823 #ifndef PRODUCT
 824     patch_field_type = result.field_type();
 825 #endif
 826   } else if (stub_id == Runtime1::load_klass_patching_id) {
 827     oop k;
 828     switch (code) {
 829       case Bytecodes::_putstatic:
 830       case Bytecodes::_getstatic:
 831         { klassOop klass = resolve_field_return_klass(caller_method, bci, CHECK);
 832           // Save a reference to the class that has to be checked for initialization
 833           init_klass = KlassHandle(THREAD, klass);
 834           k = klass->java_mirror();
 835         }
 836         break;
 837       case Bytecodes::_new:
 838         { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
 839           k = caller_method->constants()->klass_at(bnew.index(), CHECK);
 840         }
 841         break;
 842       case Bytecodes::_multianewarray:
 843         { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
 844           k = caller_method->constants()->klass_at(mna.index(), CHECK);
 845         }
 846         break;
 847       case Bytecodes::_instanceof:
 848         { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
 849           k = caller_method->constants()->klass_at(io.index(), CHECK);
 850         }
 851         break;
 852       case Bytecodes::_checkcast:
 853         { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
 854           k = caller_method->constants()->klass_at(cc.index(), CHECK);
 855         }
 856         break;
 857       case Bytecodes::_anewarray:
 858         { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
 859           klassOop ek = caller_method->constants()->klass_at(anew.index(), CHECK);
 860           k = Klass::cast(ek)->array_klass(CHECK);
 861         }
 862         break;
 863       case Bytecodes::_ldc:
 864       case Bytecodes::_ldc_w:
 865         {
 866           Bytecode_loadconstant cc(caller_method, bci);
 867           k = cc.resolve_constant(CHECK);
 868           assert(k != NULL && !k->is_klass(), "must be class mirror or other Java constant");
 869         }
 870         break;
 871       default: Unimplemented();
 872     }
 873     // convert to handle
 874     load_klass = Handle(THREAD, k);
 875   } else {
 876     ShouldNotReachHere();
 877   }
 878 
 879   if (deoptimize_for_volatile) {
 880     // At compile time we assumed the field wasn't volatile but after
 881     // loading it turns out it was volatile so we have to throw the
 882     // compiled code out and let it be regenerated.
 883     if (TracePatching) {
 884       tty->print_cr("Deoptimizing for patching volatile field reference");
 885     }
 886     // It's possible the nmethod was invalidated in the last
 887     // safepoint, but if it's still alive then make it not_entrant.
 888     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
 889     if (nm != NULL) {
 890       nm->make_not_entrant();
 891     }
 892 
 893     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 894 
 895     // Return to the now deoptimized frame.
 896   }
 897 
 898   // If we are patching in a non-perm oop, make sure the nmethod
 899   // is on the right list.
 900   if (ScavengeRootsInCode && load_klass.not_null() && load_klass->is_scavengable()) {
 901     MutexLockerEx ml_code (CodeCache_lock, Mutex::_no_safepoint_check_flag);
 902     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
 903     guarantee(nm != NULL, "only nmethods can contain non-perm oops");
 904     if (!nm->on_scavenge_root_list())
 905       CodeCache::add_scavenge_root_nmethod(nm);
 906   }
 907 
 908   // Now copy code back
 909 
 910   {
 911     MutexLockerEx ml_patch (Patching_lock, Mutex::_no_safepoint_check_flag);
 912     //
 913     // Deoptimization may have happened while we waited for the lock.
 914     // In that case we don't bother to do any patching we just return
 915     // and let the deopt happen
 916     if (!caller_is_deopted()) {
 917       NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
 918       address instr_pc = jump->jump_destination();
 919       NativeInstruction* ni = nativeInstruction_at(instr_pc);
 920       if (ni->is_jump() ) {
 921         // the jump has not been patched yet
 922         // The jump destination is slow case and therefore not part of the stubs
 923         // (stubs are only for StaticCalls)
 924 
 925         // format of buffer
 926         //    ....
 927         //    instr byte 0     <-- copy_buff
 928         //    instr byte 1
 929         //    ..
 930         //    instr byte n-1
 931         //      n
 932         //    ....             <-- call destination
 933 
 934         address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
 935         unsigned char* byte_count = (unsigned char*) (stub_location - 1);
 936         unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
 937         unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
 938         address copy_buff = stub_location - *byte_skip - *byte_count;
 939         address being_initialized_entry = stub_location - *being_initialized_entry_offset;
 940         if (TracePatching) {
 941           tty->print_cr(" Patching %s at bci %d at address 0x%x  (%s)", Bytecodes::name(code), bci,
 942                         instr_pc, (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
 943           nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
 944           assert(caller_code != NULL, "nmethod not found");
 945 
 946           // NOTE we use pc() not original_pc() because we already know they are
 947           // identical otherwise we'd have never entered this block of code
 948 
 949           OopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
 950           assert(map != NULL, "null check");
 951           map->print();
 952           tty->cr();
 953 
 954           Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
 955         }
 956         // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
 957         bool do_patch = true;
 958         if (stub_id == Runtime1::access_field_patching_id) {
 959           // The offset may not be correct if the class was not loaded at code generation time.
 960           // Set it now.
 961           NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
 962           assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
 963           assert(patch_field_offset >= 0, "illegal offset");
 964           n_move->add_offset_in_bytes(patch_field_offset);
 965         } else if (stub_id == Runtime1::load_klass_patching_id) {
 966           // If a getstatic or putstatic is referencing a klass which
 967           // isn't fully initialized, the patch body isn't copied into
 968           // place until initialization is complete.  In this case the
 969           // patch site is setup so that any threads besides the
 970           // initializing thread are forced to come into the VM and
 971           // block.
 972           do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
 973                      instanceKlass::cast(init_klass())->is_initialized();
 974           NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
 975           if (jump->jump_destination() == being_initialized_entry) {
 976             assert(do_patch == true, "initialization must be complete at this point");
 977           } else {
 978             // patch the instruction <move reg, klass>
 979             NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
 980 
 981             assert(n_copy->data() == 0 ||
 982                    n_copy->data() == (intptr_t)Universe::non_oop_word(),
 983                    "illegal init value");
 984             assert(load_klass() != NULL, "klass not set");
 985             n_copy->set_data((intx) (load_klass()));
 986 
 987             if (TracePatching) {
 988               Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
 989             }
 990 
 991 #if defined(SPARC) || defined(PPC)
 992             // Update the oop location in the nmethod with the proper
 993             // oop.  When the code was generated, a NULL was stuffed
 994             // in the oop table and that table needs to be update to
 995             // have the right value.  On intel the value is kept
 996             // directly in the instruction instead of in the oop
 997             // table, so set_data above effectively updated the value.
 998             nmethod* nm = CodeCache::find_nmethod(instr_pc);
 999             assert(nm != NULL, "invalid nmethod_pc");
1000             RelocIterator oops(nm, copy_buff, copy_buff + 1);
1001             bool found = false;
1002             while (oops.next() && !found) {
1003               if (oops.type() == relocInfo::oop_type) {
1004                 oop_Relocation* r = oops.oop_reloc();
1005                 oop* oop_adr = r->oop_addr();
1006                 *oop_adr = load_klass();
1007                 r->fix_oop_relocation();
1008                 found = true;
1009               }
1010             }
1011             assert(found, "the oop must exist!");
1012 #endif
1013 
1014           }
1015         } else {
1016           ShouldNotReachHere();
1017         }
1018         if (do_patch) {
1019           // replace instructions
1020           // first replace the tail, then the call
1021 #ifdef ARM
1022           if(stub_id == Runtime1::load_klass_patching_id && !VM_Version::supports_movw()) {
1023             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1024             oop* oop_addr = NULL;
1025             assert(nm != NULL, "invalid nmethod_pc");
1026             RelocIterator oops(nm, copy_buff, copy_buff + 1);
1027             while (oops.next()) {
1028               if (oops.type() == relocInfo::oop_type) {
1029                 oop_Relocation* r = oops.oop_reloc();
1030                 oop_addr = r->oop_addr();
1031                 break;
1032               }
1033             }
1034             assert(oop_addr != NULL, "oop relocation must exist");
1035             copy_buff -= *byte_count;
1036             NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1037             n_copy2->set_pc_relative_offset((address)oop_addr, instr_pc);
1038           }
1039 #endif
1040 
1041           for (int i = NativeCall::instruction_size; i < *byte_count; i++) {
1042             address ptr = copy_buff + i;
1043             int a_byte = (*ptr) & 0xFF;
1044             address dst = instr_pc + i;
1045             *(unsigned char*)dst = (unsigned char) a_byte;
1046           }
1047           ICache::invalidate_range(instr_pc, *byte_count);
1048           NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1049 
1050           if (stub_id == Runtime1::load_klass_patching_id) {
1051             // update relocInfo to oop
1052             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1053             assert(nm != NULL, "invalid nmethod_pc");
1054 
1055             // The old patch site is now a move instruction so update
1056             // the reloc info so that it will get updated during
1057             // future GCs.
1058             RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1059             relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1060                                                      relocInfo::none, relocInfo::oop_type);
1061 #ifdef SPARC
1062             // Sparc takes two relocations for an oop so update the second one.
1063             address instr_pc2 = instr_pc + NativeMovConstReg::add_offset;
1064             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1065             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1066                                                      relocInfo::none, relocInfo::oop_type);
1067 #endif
1068 #ifdef PPC
1069           { address instr_pc2 = instr_pc + NativeMovConstReg::lo_offset;
1070             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1071             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2, relocInfo::none, relocInfo::oop_type);
1072           }
1073 #endif
1074           }
1075 
1076         } else {
1077           ICache::invalidate_range(copy_buff, *byte_count);
1078           NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1079         }
1080       }
1081     }
1082   }
1083 JRT_END
1084 
1085 //
1086 // Entry point for compiled code. We want to patch a nmethod.
1087 // We don't do a normal VM transition here because we want to
1088 // know after the patching is complete and any safepoint(s) are taken
1089 // if the calling nmethod was deoptimized. We do this by calling a
1090 // helper method which does the normal VM transition and when it
1091 // completes we can check for deoptimization. This simplifies the
1092 // assembly code in the cpu directories.
1093 //
1094 int Runtime1::move_klass_patching(JavaThread* thread) {
1095 //
1096 // NOTE: we are still in Java
1097 //
1098   Thread* THREAD = thread;
1099   debug_only(NoHandleMark nhm;)
1100   {
1101     // Enter VM mode
1102 
1103     ResetNoHandleMark rnhm;
1104     patch_code(thread, load_klass_patching_id);
1105   }
1106   // Back in JAVA, use no oops DON'T safepoint
1107 
1108   // Return true if calling code is deoptimized
1109 
1110   return caller_is_deopted();
1111 }
1112 
1113 //
1114 // Entry point for compiled code. We want to patch a nmethod.
1115 // We don't do a normal VM transition here because we want to
1116 // know after the patching is complete and any safepoint(s) are taken
1117 // if the calling nmethod was deoptimized. We do this by calling a
1118 // helper method which does the normal VM transition and when it
1119 // completes we can check for deoptimization. This simplifies the
1120 // assembly code in the cpu directories.
1121 //
1122 
1123 int Runtime1::access_field_patching(JavaThread* thread) {
1124 //
1125 // NOTE: we are still in Java
1126 //
1127   Thread* THREAD = thread;
1128   debug_only(NoHandleMark nhm;)
1129   {
1130     // Enter VM mode
1131 
1132     ResetNoHandleMark rnhm;
1133     patch_code(thread, access_field_patching_id);
1134   }
1135   // Back in JAVA, use no oops DON'T safepoint
1136 
1137   // Return true if calling code is deoptimized
1138 
1139   return caller_is_deopted();
1140 JRT_END
1141 
1142 
1143 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1144   // for now we just print out the block id
1145   tty->print("%d ", block_id);
1146 JRT_END
1147 
1148 
1149 // Array copy return codes.
1150 enum {
1151   ac_failed = -1, // arraycopy failed
1152   ac_ok = 0       // arraycopy succeeded
1153 };
1154 
1155 
1156 // Below length is the # elements copied.
1157 template <class T> int obj_arraycopy_work(oopDesc* src, T* src_addr,
1158                                           oopDesc* dst, T* dst_addr,
1159                                           int length) {
1160 
1161   // For performance reasons, we assume we are using a card marking write
1162   // barrier. The assert will fail if this is not the case.
1163   // Note that we use the non-virtual inlineable variant of write_ref_array.
1164   BarrierSet* bs = Universe::heap()->barrier_set();
1165   assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
1166   assert(bs->has_write_ref_array_pre_opt(), "For pre-barrier as well.");
1167   if (src == dst) {
1168     // same object, no check
1169     bs->write_ref_array_pre(dst_addr, length);
1170     Copy::conjoint_oops_atomic(src_addr, dst_addr, length);
1171     bs->write_ref_array((HeapWord*)dst_addr, length);
1172     return ac_ok;
1173   } else {
1174     klassOop bound = objArrayKlass::cast(dst->klass())->element_klass();
1175     klassOop stype = objArrayKlass::cast(src->klass())->element_klass();
1176     if (stype == bound || Klass::cast(stype)->is_subtype_of(bound)) {
1177       // Elements are guaranteed to be subtypes, so no check necessary
1178       bs->write_ref_array_pre(dst_addr, length);
1179       Copy::conjoint_oops_atomic(src_addr, dst_addr, length);
1180       bs->write_ref_array((HeapWord*)dst_addr, length);
1181       return ac_ok;
1182     }
1183   }
1184   return ac_failed;
1185 }
1186 
1187 // fast and direct copy of arrays; returning -1, means that an exception may be thrown
1188 // and we did not copy anything
1189 JRT_LEAF(int, Runtime1::arraycopy(oopDesc* src, int src_pos, oopDesc* dst, int dst_pos, int length))
1190 #ifndef PRODUCT
1191   _generic_arraycopy_cnt++;        // Slow-path oop array copy
1192 #endif
1193 
1194   if (src == NULL || dst == NULL || src_pos < 0 || dst_pos < 0 || length < 0) return ac_failed;
1195   if (!dst->is_array() || !src->is_array()) return ac_failed;
1196   if ((unsigned int) arrayOop(src)->length() < (unsigned int)src_pos + (unsigned int)length) return ac_failed;
1197   if ((unsigned int) arrayOop(dst)->length() < (unsigned int)dst_pos + (unsigned int)length) return ac_failed;
1198 
1199   if (length == 0) return ac_ok;
1200   if (src->is_typeArray()) {
1201     const klassOop klass_oop = src->klass();
1202     if (klass_oop != dst->klass()) return ac_failed;
1203     typeArrayKlass* klass = typeArrayKlass::cast(klass_oop);
1204     const int l2es = klass->log2_element_size();
1205     const int ihs = klass->array_header_in_bytes() / wordSize;
1206     char* src_addr = (char*) ((oopDesc**)src + ihs) + (src_pos << l2es);
1207     char* dst_addr = (char*) ((oopDesc**)dst + ihs) + (dst_pos << l2es);
1208     // Potential problem: memmove is not guaranteed to be word atomic
1209     // Revisit in Merlin
1210     memmove(dst_addr, src_addr, length << l2es);
1211     return ac_ok;
1212   } else if (src->is_objArray() && dst->is_objArray()) {
1213     if (UseCompressedOops) {
1214       narrowOop *src_addr  = objArrayOop(src)->obj_at_addr<narrowOop>(src_pos);
1215       narrowOop *dst_addr  = objArrayOop(dst)->obj_at_addr<narrowOop>(dst_pos);
1216       return obj_arraycopy_work(src, src_addr, dst, dst_addr, length);
1217     } else {
1218       oop *src_addr  = objArrayOop(src)->obj_at_addr<oop>(src_pos);
1219       oop *dst_addr  = objArrayOop(dst)->obj_at_addr<oop>(dst_pos);
1220       return obj_arraycopy_work(src, src_addr, dst, dst_addr, length);
1221     }
1222   }
1223   return ac_failed;
1224 JRT_END
1225 
1226 
1227 JRT_LEAF(void, Runtime1::primitive_arraycopy(HeapWord* src, HeapWord* dst, int length))
1228 #ifndef PRODUCT
1229   _primitive_arraycopy_cnt++;
1230 #endif
1231 
1232   if (length == 0) return;
1233   // Not guaranteed to be word atomic, but that doesn't matter
1234   // for anything but an oop array, which is covered by oop_arraycopy.
1235   Copy::conjoint_jbytes(src, dst, length);
1236 JRT_END
1237 
1238 JRT_LEAF(void, Runtime1::oop_arraycopy(HeapWord* src, HeapWord* dst, int num))
1239 #ifndef PRODUCT
1240   _oop_arraycopy_cnt++;
1241 #endif
1242 
1243   if (num == 0) return;
1244   BarrierSet* bs = Universe::heap()->barrier_set();
1245   assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
1246   assert(bs->has_write_ref_array_pre_opt(), "For pre-barrier as well.");
1247   if (UseCompressedOops) {
1248     bs->write_ref_array_pre((narrowOop*)dst, num);
1249     Copy::conjoint_oops_atomic((narrowOop*) src, (narrowOop*) dst, num);
1250   } else {
1251     bs->write_ref_array_pre((oop*)dst, num);
1252     Copy::conjoint_oops_atomic((oop*) src, (oop*) dst, num);
1253   }
1254   bs->write_ref_array(dst, num);
1255 JRT_END
1256 
1257 
1258 #ifndef PRODUCT
1259 void Runtime1::print_statistics() {
1260   tty->print_cr("C1 Runtime statistics:");
1261   tty->print_cr(" _resolve_invoke_virtual_cnt:     %d", SharedRuntime::_resolve_virtual_ctr);
1262   tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %d", SharedRuntime::_resolve_opt_virtual_ctr);
1263   tty->print_cr(" _resolve_invoke_static_cnt:      %d", SharedRuntime::_resolve_static_ctr);
1264   tty->print_cr(" _handle_wrong_method_cnt:        %d", SharedRuntime::_wrong_method_ctr);
1265   tty->print_cr(" _ic_miss_cnt:                    %d", SharedRuntime::_ic_miss_ctr);
1266   tty->print_cr(" _generic_arraycopy_cnt:          %d", _generic_arraycopy_cnt);
1267   tty->print_cr(" _generic_arraycopystub_cnt:      %d", _generic_arraycopystub_cnt);
1268   tty->print_cr(" _byte_arraycopy_cnt:             %d", _byte_arraycopy_cnt);
1269   tty->print_cr(" _short_arraycopy_cnt:            %d", _short_arraycopy_cnt);
1270   tty->print_cr(" _int_arraycopy_cnt:              %d", _int_arraycopy_cnt);
1271   tty->print_cr(" _long_arraycopy_cnt:             %d", _long_arraycopy_cnt);
1272   tty->print_cr(" _primitive_arraycopy_cnt:        %d", _primitive_arraycopy_cnt);
1273   tty->print_cr(" _oop_arraycopy_cnt (C):          %d", Runtime1::_oop_arraycopy_cnt);
1274   tty->print_cr(" _oop_arraycopy_cnt (stub):       %d", _oop_arraycopy_cnt);
1275   tty->print_cr(" _arraycopy_slowcase_cnt:         %d", _arraycopy_slowcase_cnt);
1276   tty->print_cr(" _arraycopy_checkcast_cnt:        %d", _arraycopy_checkcast_cnt);
1277   tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%d", _arraycopy_checkcast_attempt_cnt);
1278 
1279   tty->print_cr(" _new_type_array_slowcase_cnt:    %d", _new_type_array_slowcase_cnt);
1280   tty->print_cr(" _new_object_array_slowcase_cnt:  %d", _new_object_array_slowcase_cnt);
1281   tty->print_cr(" _new_instance_slowcase_cnt:      %d", _new_instance_slowcase_cnt);
1282   tty->print_cr(" _new_multi_array_slowcase_cnt:   %d", _new_multi_array_slowcase_cnt);
1283   tty->print_cr(" _monitorenter_slowcase_cnt:      %d", _monitorenter_slowcase_cnt);
1284   tty->print_cr(" _monitorexit_slowcase_cnt:       %d", _monitorexit_slowcase_cnt);
1285   tty->print_cr(" _patch_code_slowcase_cnt:        %d", _patch_code_slowcase_cnt);
1286 
1287   tty->print_cr(" _throw_range_check_exception_count:            %d:", _throw_range_check_exception_count);
1288   tty->print_cr(" _throw_index_exception_count:                  %d:", _throw_index_exception_count);
1289   tty->print_cr(" _throw_div0_exception_count:                   %d:", _throw_div0_exception_count);
1290   tty->print_cr(" _throw_null_pointer_exception_count:           %d:", _throw_null_pointer_exception_count);
1291   tty->print_cr(" _throw_class_cast_exception_count:             %d:", _throw_class_cast_exception_count);
1292   tty->print_cr(" _throw_incompatible_class_change_error_count:  %d:", _throw_incompatible_class_change_error_count);
1293   tty->print_cr(" _throw_array_store_exception_count:            %d:", _throw_array_store_exception_count);
1294   tty->print_cr(" _throw_count:                                  %d:", _throw_count);
1295 
1296   SharedRuntime::print_ic_miss_histogram();
1297   tty->cr();
1298 }
1299 #endif // PRODUCT