1 /*
   2  * Copyright (c) 1999, 2021, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "asm/codeBuffer.hpp"
  27 #include "c1/c1_CodeStubs.hpp"
  28 #include "c1/c1_Defs.hpp"
  29 #include "c1/c1_FrameMap.hpp"
  30 #include "c1/c1_LIRAssembler.hpp"
  31 #include "c1/c1_MacroAssembler.hpp"
  32 #include "c1/c1_Runtime1.hpp"
  33 #include "classfile/javaClasses.inline.hpp"
  34 #include "classfile/vmClasses.hpp"
  35 #include "classfile/vmSymbols.hpp"
  36 #include "code/codeBlob.hpp"
  37 #include "code/compiledIC.hpp"
  38 #include "code/pcDesc.hpp"
  39 #include "code/scopeDesc.hpp"
  40 #include "code/vtableStubs.hpp"
  41 #include "compiler/compilationPolicy.hpp"
  42 #include "compiler/disassembler.hpp"
  43 #include "compiler/oopMap.hpp"
  44 #include "gc/shared/barrierSet.hpp"
  45 #include "gc/shared/c1/barrierSetC1.hpp"
  46 #include "gc/shared/collectedHeap.hpp"
  47 #include "interpreter/bytecode.hpp"
  48 #include "interpreter/interpreter.hpp"
  49 #include "jfr/support/jfrIntrinsics.hpp"
  50 #include "logging/log.hpp"
  51 #include "memory/allocation.inline.hpp"
  52 #include "memory/oopFactory.hpp"
  53 #include "memory/resourceArea.hpp"
  54 #include "memory/universe.hpp"
  55 #include "oops/access.inline.hpp"
  56 #include "oops/klass.inline.hpp"
  57 #include "oops/objArrayOop.inline.hpp"
  58 #include "oops/objArrayKlass.hpp"
  59 #include "oops/oop.inline.hpp"
  60 #include "prims/jvmtiExport.hpp"
  61 #include "runtime/atomic.hpp"
  62 #include "runtime/fieldDescriptor.inline.hpp"
  63 #include "runtime/frame.inline.hpp"
  64 #include "runtime/handles.inline.hpp"
  65 #include "runtime/interfaceSupport.inline.hpp"
  66 #include "runtime/javaCalls.hpp"
  67 #include "runtime/sharedRuntime.hpp"
  68 #include "runtime/stackWatermarkSet.hpp"
  69 #include "runtime/stubRoutines.hpp"
  70 #include "runtime/threadCritical.hpp"
  71 #include "runtime/vframe.inline.hpp"
  72 #include "runtime/vframeArray.hpp"
  73 #include "runtime/vm_version.hpp"
  74 #include "utilities/copy.hpp"
  75 #include "utilities/events.hpp"
  76 
  77 
  78 // Implementation of StubAssembler
  79 
  80 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
  81   _name = name;
  82   _must_gc_arguments = false;
  83   _frame_size = no_frame_size;
  84   _num_rt_args = 0;
  85   _stub_id = stub_id;
  86 }
  87 
  88 
  89 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
  90   _name = name;
  91   _must_gc_arguments = must_gc_arguments;
  92 }
  93 
  94 
  95 void StubAssembler::set_frame_size(int size) {
  96   if (_frame_size == no_frame_size) {
  97     _frame_size = size;
  98   }
  99   assert(_frame_size == size, "can't change the frame size");
 100 }
 101 
 102 
 103 void StubAssembler::set_num_rt_args(int args) {
 104   if (_num_rt_args == 0) {
 105     _num_rt_args = args;
 106   }
 107   assert(_num_rt_args == args, "can't change the number of args");
 108 }
 109 
 110 // Implementation of Runtime1
 111 
 112 CodeBlob* Runtime1::_blobs[Runtime1::number_of_ids];
 113 const char *Runtime1::_blob_names[] = {
 114   RUNTIME1_STUBS(STUB_NAME, LAST_STUB_NAME)
 115 };
 116 
 117 #ifndef PRODUCT
 118 // statistics
 119 int Runtime1::_generic_arraycopystub_cnt = 0;
 120 int Runtime1::_arraycopy_slowcase_cnt = 0;
 121 int Runtime1::_arraycopy_checkcast_cnt = 0;
 122 int Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
 123 int Runtime1::_new_type_array_slowcase_cnt = 0;
 124 int Runtime1::_new_object_array_slowcase_cnt = 0;
 125 int Runtime1::_new_instance_slowcase_cnt = 0;
 126 int Runtime1::_new_multi_array_slowcase_cnt = 0;
 127 int Runtime1::_monitorenter_slowcase_cnt = 0;
 128 int Runtime1::_monitorexit_slowcase_cnt = 0;
 129 int Runtime1::_patch_code_slowcase_cnt = 0;
 130 int Runtime1::_throw_range_check_exception_count = 0;
 131 int Runtime1::_throw_index_exception_count = 0;
 132 int Runtime1::_throw_div0_exception_count = 0;
 133 int Runtime1::_throw_null_pointer_exception_count = 0;
 134 int Runtime1::_throw_class_cast_exception_count = 0;
 135 int Runtime1::_throw_incompatible_class_change_error_count = 0;
 136 int Runtime1::_throw_count = 0;
 137 
 138 static int _byte_arraycopy_stub_cnt = 0;
 139 static int _short_arraycopy_stub_cnt = 0;
 140 static int _int_arraycopy_stub_cnt = 0;
 141 static int _long_arraycopy_stub_cnt = 0;
 142 static int _oop_arraycopy_stub_cnt = 0;
 143 
 144 address Runtime1::arraycopy_count_address(BasicType type) {
 145   switch (type) {
 146   case T_BOOLEAN:
 147   case T_BYTE:   return (address)&_byte_arraycopy_stub_cnt;
 148   case T_CHAR:
 149   case T_SHORT:  return (address)&_short_arraycopy_stub_cnt;
 150   case T_FLOAT:
 151   case T_INT:    return (address)&_int_arraycopy_stub_cnt;
 152   case T_DOUBLE:
 153   case T_LONG:   return (address)&_long_arraycopy_stub_cnt;
 154   case T_ARRAY:
 155   case T_OBJECT: return (address)&_oop_arraycopy_stub_cnt;
 156   default:
 157     ShouldNotReachHere();
 158     return NULL;
 159   }
 160 }
 161 
 162 
 163 #endif
 164 
 165 // Simple helper to see if the caller of a runtime stub which
 166 // entered the VM has been deoptimized
 167 
 168 static bool caller_is_deopted(JavaThread* current) {
 169   RegisterMap reg_map(current, false);
 170   frame runtime_frame = current->last_frame();
 171   frame caller_frame = runtime_frame.sender(&reg_map);
 172   assert(caller_frame.is_compiled_frame(), "must be compiled");
 173   return caller_frame.is_deoptimized_frame();
 174 }
 175 
 176 // Stress deoptimization
 177 static void deopt_caller(JavaThread* current) {
 178   if (!caller_is_deopted(current)) {
 179     RegisterMap reg_map(current, false);
 180     frame runtime_frame = current->last_frame();
 181     frame caller_frame = runtime_frame.sender(&reg_map);
 182     Deoptimization::deoptimize_frame(current, caller_frame.id());
 183     assert(caller_is_deopted(current), "Must be deoptimized");
 184   }
 185 }
 186 
 187 class StubIDStubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
 188  private:
 189   Runtime1::StubID _id;
 190  public:
 191   StubIDStubAssemblerCodeGenClosure(Runtime1::StubID id) : _id(id) {}
 192   virtual OopMapSet* generate_code(StubAssembler* sasm) {
 193     return Runtime1::generate_code_for(_id, sasm);
 194   }
 195 };
 196 
 197 CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, int stub_id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
 198   ResourceMark rm;
 199   // create code buffer for code storage
 200   CodeBuffer code(buffer_blob);
 201 
 202   OopMapSet* oop_maps;
 203   int frame_size;
 204   bool must_gc_arguments;
 205 
 206   Compilation::setup_code_buffer(&code, 0);
 207 
 208   // create assembler for code generation
 209   StubAssembler* sasm = new StubAssembler(&code, name, stub_id);
 210   // generate code for runtime stub
 211   oop_maps = cl->generate_code(sasm);
 212   assert(oop_maps == NULL || sasm->frame_size() != no_frame_size,
 213          "if stub has an oop map it must have a valid frame size");
 214   assert(!expect_oop_map || oop_maps != NULL, "must have an oopmap");
 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 
 221   frame_size = sasm->frame_size();
 222   must_gc_arguments = sasm->must_gc_arguments();
 223   // create blob - distinguish a few special cases
 224   CodeBlob* blob = RuntimeStub::new_runtime_stub(name,
 225                                                  &code,
 226                                                  CodeOffsets::frame_never_safe,
 227                                                  frame_size,
 228                                                  oop_maps,
 229                                                  must_gc_arguments);
 230   assert(blob != NULL, "blob must exist");
 231   return blob;
 232 }
 233 
 234 void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
 235   assert(0 <= id && id < number_of_ids, "illegal stub id");
 236   bool expect_oop_map = true;
 237 #ifdef ASSERT
 238   // Make sure that stubs that need oopmaps have them
 239   switch (id) {
 240     // These stubs don't need to have an oopmap
 241   case dtrace_object_alloc_id:
 242   case slow_subtype_check_id:
 243   case fpu2long_stub_id:
 244   case unwind_exception_id:
 245   case counter_overflow_id:
 246 #if defined(PPC32)
 247   case handle_exception_nofpu_id:
 248 #endif
 249     expect_oop_map = false;
 250     break;
 251   default:
 252     break;
 253   }
 254 #endif
 255   StubIDStubAssemblerCodeGenClosure cl(id);
 256   CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
 257   // install blob
 258   _blobs[id] = blob;
 259 }
 260 
 261 void Runtime1::initialize(BufferBlob* blob) {
 262   // platform-dependent initialization
 263   initialize_pd();
 264   // generate stubs
 265   for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
 266   // printing
 267 #ifndef PRODUCT
 268   if (PrintSimpleStubs) {
 269     ResourceMark rm;
 270     for (int id = 0; id < number_of_ids; id++) {
 271       _blobs[id]->print();
 272       if (_blobs[id]->oop_maps() != NULL) {
 273         _blobs[id]->oop_maps()->print();
 274       }
 275     }
 276   }
 277 #endif
 278   BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
 279   bs->generate_c1_runtime_stubs(blob);
 280 }
 281 
 282 CodeBlob* Runtime1::blob_for(StubID id) {
 283   assert(0 <= id && id < number_of_ids, "illegal stub id");
 284   return _blobs[id];
 285 }
 286 
 287 
 288 const char* Runtime1::name_for(StubID id) {
 289   assert(0 <= id && id < number_of_ids, "illegal stub id");
 290   return _blob_names[id];
 291 }
 292 
 293 const char* Runtime1::name_for_address(address entry) {
 294   for (int id = 0; id < number_of_ids; id++) {
 295     if (entry == entry_for((StubID)id)) return name_for((StubID)id);
 296   }
 297 
 298 #define FUNCTION_CASE(a, f) \
 299   if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f))  return #f
 300 
 301   FUNCTION_CASE(entry, os::javaTimeMillis);
 302   FUNCTION_CASE(entry, os::javaTimeNanos);
 303   FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
 304   FUNCTION_CASE(entry, SharedRuntime::d2f);
 305   FUNCTION_CASE(entry, SharedRuntime::d2i);
 306   FUNCTION_CASE(entry, SharedRuntime::d2l);
 307   FUNCTION_CASE(entry, SharedRuntime::dcos);
 308   FUNCTION_CASE(entry, SharedRuntime::dexp);
 309   FUNCTION_CASE(entry, SharedRuntime::dlog);
 310   FUNCTION_CASE(entry, SharedRuntime::dlog10);
 311   FUNCTION_CASE(entry, SharedRuntime::dpow);
 312   FUNCTION_CASE(entry, SharedRuntime::drem);
 313   FUNCTION_CASE(entry, SharedRuntime::dsin);
 314   FUNCTION_CASE(entry, SharedRuntime::dtan);
 315   FUNCTION_CASE(entry, SharedRuntime::f2i);
 316   FUNCTION_CASE(entry, SharedRuntime::f2l);
 317   FUNCTION_CASE(entry, SharedRuntime::frem);
 318   FUNCTION_CASE(entry, SharedRuntime::l2d);
 319   FUNCTION_CASE(entry, SharedRuntime::l2f);
 320   FUNCTION_CASE(entry, SharedRuntime::ldiv);
 321   FUNCTION_CASE(entry, SharedRuntime::lmul);
 322   FUNCTION_CASE(entry, SharedRuntime::lrem);
 323   FUNCTION_CASE(entry, SharedRuntime::lrem);
 324   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
 325   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
 326   FUNCTION_CASE(entry, is_instance_of);
 327   FUNCTION_CASE(entry, trace_block_entry);
 328 #ifdef JFR_HAVE_INTRINSICS
 329   FUNCTION_CASE(entry, JFR_TIME_FUNCTION);
 330 #endif
 331   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
 332   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
 333   FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
 334   FUNCTION_CASE(entry, StubRoutines::dexp());
 335   FUNCTION_CASE(entry, StubRoutines::dlog());
 336   FUNCTION_CASE(entry, StubRoutines::dlog10());
 337   FUNCTION_CASE(entry, StubRoutines::dpow());
 338   FUNCTION_CASE(entry, StubRoutines::dsin());
 339   FUNCTION_CASE(entry, StubRoutines::dcos());
 340   FUNCTION_CASE(entry, StubRoutines::dtan());
 341 
 342 #undef FUNCTION_CASE
 343 
 344   // Soft float adds more runtime names.
 345   return pd_name_for_address(entry);
 346 }
 347 
 348 
 349 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* current, Klass* klass))
 350 #ifndef PRODUCT
 351   if (PrintC1Statistics) {
 352     _new_instance_slowcase_cnt++;
 353   }
 354 #endif
 355   assert(klass->is_klass(), "not a class");
 356   Handle holder(current, klass->klass_holder()); // keep the klass alive
 357   InstanceKlass* h = InstanceKlass::cast(klass);
 358   h->check_valid_for_instantiation(true, CHECK);
 359   // make sure klass is initialized
 360   h->initialize(CHECK);
 361   // allocate instance and return via TLS
 362   oop obj = h->allocate_instance(CHECK);
 363   current->set_vm_result(obj);
 364 JRT_END
 365 
 366 
 367 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* current, Klass* klass, jint length))
 368 #ifndef PRODUCT
 369   if (PrintC1Statistics) {
 370     _new_type_array_slowcase_cnt++;
 371   }
 372 #endif
 373   // Note: no handle for klass needed since they are not used
 374   //       anymore after new_typeArray() and no GC can happen before.
 375   //       (This may have to change if this code changes!)
 376   assert(klass->is_klass(), "not a class");
 377   BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
 378   oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
 379   current->set_vm_result(obj);
 380   // This is pretty rare but this runtime patch is stressful to deoptimization
 381   // if we deoptimize here so force a deopt to stress the path.
 382   if (DeoptimizeALot) {
 383     deopt_caller(current);
 384   }
 385 
 386 JRT_END
 387 
 388 
 389 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* current, Klass* array_klass, jint length))
 390 #ifndef PRODUCT
 391   if (PrintC1Statistics) {
 392     _new_object_array_slowcase_cnt++;
 393   }
 394 #endif
 395   // Note: no handle for klass needed since they are not used
 396   //       anymore after new_objArray() and no GC can happen before.
 397   //       (This may have to change if this code changes!)
 398   assert(array_klass->is_klass(), "not a class");
 399   Handle holder(current, array_klass->klass_holder()); // keep the klass alive
 400   Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
 401   objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
 402   current->set_vm_result(obj);
 403   // This is pretty rare but this runtime patch is stressful to deoptimization
 404   // if we deoptimize here so force a deopt to stress the path.
 405   if (DeoptimizeALot) {
 406     deopt_caller(current);
 407   }
 408 JRT_END
 409 
 410 
 411 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* current, Klass* klass, int rank, jint* dims))
 412 #ifndef PRODUCT
 413   if (PrintC1Statistics) {
 414     _new_multi_array_slowcase_cnt++;
 415   }
 416 #endif
 417   assert(klass->is_klass(), "not a class");
 418   assert(rank >= 1, "rank must be nonzero");
 419   Handle holder(current, klass->klass_holder()); // keep the klass alive
 420   oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
 421   current->set_vm_result(obj);
 422 JRT_END
 423 
 424 
 425 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* current, StubID id))
 426   tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
 427 JRT_END
 428 
 429 
 430 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* current, oopDesc* obj))
 431   ResourceMark rm(current);
 432   const char* klass_name = obj->klass()->external_name();
 433   SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayStoreException(), klass_name);
 434 JRT_END
 435 
 436 
 437 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
 438 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
 439 // method) method is passed as an argument. In order to do that it is embedded in the code as
 440 // a constant.
 441 static nmethod* counter_overflow_helper(JavaThread* current, int branch_bci, Method* m) {
 442   nmethod* osr_nm = NULL;
 443   methodHandle method(current, m);
 444 
 445   RegisterMap map(current, false);
 446   frame fr =  current->last_frame().sender(&map);
 447   nmethod* nm = (nmethod*) fr.cb();
 448   assert(nm!= NULL && nm->is_nmethod(), "Sanity check");
 449   methodHandle enclosing_method(current, nm->method());
 450 
 451   CompLevel level = (CompLevel)nm->comp_level();
 452   int bci = InvocationEntryBci;
 453   if (branch_bci != InvocationEntryBci) {
 454     // Compute destination bci
 455     address pc = method()->code_base() + branch_bci;
 456     Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
 457     int offset = 0;
 458     switch (branch) {
 459       case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
 460       case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
 461       case Bytecodes::_if_icmple: case Bytecodes::_ifle:
 462       case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
 463       case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
 464       case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
 465       case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
 466         offset = (int16_t)Bytes::get_Java_u2(pc + 1);
 467         break;
 468       case Bytecodes::_goto_w:
 469         offset = Bytes::get_Java_u4(pc + 1);
 470         break;
 471       default: ;
 472     }
 473     bci = branch_bci + offset;
 474   }
 475   osr_nm = CompilationPolicy::event(enclosing_method, method, branch_bci, bci, level, nm, current);
 476   return osr_nm;
 477 }
 478 
 479 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* current, int bci, Method* method))
 480   nmethod* osr_nm;
 481   JRT_BLOCK
 482     osr_nm = counter_overflow_helper(current, bci, method);
 483     if (osr_nm != NULL) {
 484       RegisterMap map(current, false);
 485       frame fr =  current->last_frame().sender(&map);
 486       Deoptimization::deoptimize_frame(current, fr.id());
 487     }
 488   JRT_BLOCK_END
 489   return NULL;
 490 JRT_END
 491 
 492 extern void vm_exit(int code);
 493 
 494 // Enter this method from compiled code handler below. This is where we transition
 495 // to VM mode. This is done as a helper routine so that the method called directly
 496 // from compiled code does not have to transition to VM. This allows the entry
 497 // method to see if the nmethod that we have just looked up a handler for has
 498 // been deoptimized while we were in the vm. This simplifies the assembly code
 499 // cpu directories.
 500 //
 501 // We are entering here from exception stub (via the entry method below)
 502 // If there is a compiled exception handler in this method, we will continue there;
 503 // otherwise we will unwind the stack and continue at the caller of top frame method
 504 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
 505 // control the area where we can allow a safepoint. After we exit the safepoint area we can
 506 // check to see if the handler we are going to return is now in a nmethod that has
 507 // been deoptimized. If that is the case we return the deopt blob
 508 // unpack_with_exception entry instead. This makes life for the exception blob easier
 509 // because making that same check and diverting is painful from assembly language.
 510 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* current, oopDesc* ex, address pc, nmethod*& nm))
 511   // Reset method handle flag.
 512   current->set_is_method_handle_return(false);
 513 
 514   Handle exception(current, ex);
 515 
 516   // This function is called when we are about to throw an exception. Therefore,
 517   // we have to poll the stack watermark barrier to make sure that not yet safe
 518   // stack frames are made safe before returning into them.
 519   if (current->last_frame().cb() == Runtime1::blob_for(Runtime1::handle_exception_from_callee_id)) {
 520     // The Runtime1::handle_exception_from_callee_id handler is invoked after the
 521     // frame has been unwound. It instead builds its own stub frame, to call the
 522     // runtime. But the throwing frame has already been unwound here.
 523     StackWatermarkSet::after_unwind(current);
 524   }
 525 
 526   nm = CodeCache::find_nmethod(pc);
 527   assert(nm != NULL, "this is not an nmethod");
 528   // Adjust the pc as needed/
 529   if (nm->is_deopt_pc(pc)) {
 530     RegisterMap map(current, false);
 531     frame exception_frame = current->last_frame().sender(&map);
 532     // if the frame isn't deopted then pc must not correspond to the caller of last_frame
 533     assert(exception_frame.is_deoptimized_frame(), "must be deopted");
 534     pc = exception_frame.pc();
 535   }
 536   assert(exception.not_null(), "NULL exceptions should be handled by throw_exception");
 537   // Check that exception is a subclass of Throwable
 538   assert(exception->is_a(vmClasses::Throwable_klass()),
 539          "Exception not subclass of Throwable");
 540 
 541   // debugging support
 542   // tracing
 543   if (log_is_enabled(Info, exceptions)) {
 544     ResourceMark rm;
 545     stringStream tempst;
 546     assert(nm->method() != NULL, "Unexpected NULL method()");
 547     tempst.print("C1 compiled method <%s>\n"
 548                  " at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
 549                  nm->method()->print_value_string(), p2i(pc), p2i(current));
 550     Exceptions::log_exception(exception, tempst.as_string());
 551   }
 552   // for AbortVMOnException flag
 553   Exceptions::debug_check_abort(exception);
 554 
 555   // Check the stack guard pages and reenable them if necessary and there is
 556   // enough space on the stack to do so.  Use fast exceptions only if the guard
 557   // pages are enabled.
 558   bool guard_pages_enabled = current->stack_overflow_state()->reguard_stack_if_needed();
 559 
 560   if (JvmtiExport::can_post_on_exceptions()) {
 561     // To ensure correct notification of exception catches and throws
 562     // we have to deoptimize here.  If we attempted to notify the
 563     // catches and throws during this exception lookup it's possible
 564     // we could deoptimize on the way out of the VM and end back in
 565     // the interpreter at the throw site.  This would result in double
 566     // notifications since the interpreter would also notify about
 567     // these same catches and throws as it unwound the frame.
 568 
 569     RegisterMap reg_map(current);
 570     frame stub_frame = current->last_frame();
 571     frame caller_frame = stub_frame.sender(&reg_map);
 572 
 573     // We don't really want to deoptimize the nmethod itself since we
 574     // can actually continue in the exception handler ourselves but I
 575     // don't see an easy way to have the desired effect.
 576     Deoptimization::deoptimize_frame(current, caller_frame.id());
 577     assert(caller_is_deopted(current), "Must be deoptimized");
 578 
 579     return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 580   }
 581 
 582   // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
 583   if (guard_pages_enabled) {
 584     address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
 585     if (fast_continuation != NULL) {
 586       // Set flag if return address is a method handle call site.
 587       current->set_is_method_handle_return(nm->is_method_handle_return(pc));
 588       return fast_continuation;
 589     }
 590   }
 591 
 592   // If the stack guard pages are enabled, check whether there is a handler in
 593   // the current method.  Otherwise (guard pages disabled), force an unwind and
 594   // skip the exception cache update (i.e., just leave continuation==NULL).
 595   address continuation = NULL;
 596   if (guard_pages_enabled) {
 597 
 598     // New exception handling mechanism can support inlined methods
 599     // with exception handlers since the mappings are from PC to PC
 600 
 601     // Clear out the exception oop and pc since looking up an
 602     // exception handler can cause class loading, which might throw an
 603     // exception and those fields are expected to be clear during
 604     // normal bytecode execution.
 605     current->clear_exception_oop_and_pc();
 606 
 607     bool recursive_exception = false;
 608     continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
 609     // If an exception was thrown during exception dispatch, the exception oop may have changed
 610     current->set_exception_oop(exception());
 611     current->set_exception_pc(pc);
 612 
 613     // the exception cache is used only by non-implicit exceptions
 614     // Update the exception cache only when there didn't happen
 615     // another exception during the computation of the compiled
 616     // exception handler. Checking for exception oop equality is not
 617     // sufficient because some exceptions are pre-allocated and reused.
 618     if (continuation != NULL && !recursive_exception) {
 619       nm->add_handler_for_exception_and_pc(exception, pc, continuation);
 620     }
 621   }
 622 
 623   current->set_vm_result(exception());
 624   // Set flag if return address is a method handle call site.
 625   current->set_is_method_handle_return(nm->is_method_handle_return(pc));
 626 
 627   if (log_is_enabled(Info, exceptions)) {
 628     ResourceMark rm;
 629     log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
 630                          " for exception thrown at PC " PTR_FORMAT,
 631                          p2i(current), p2i(continuation), p2i(pc));
 632   }
 633 
 634   return continuation;
 635 JRT_END
 636 
 637 // Enter this method from compiled code only if there is a Java exception handler
 638 // in the method handling the exception.
 639 // We are entering here from exception stub. We don't do a normal VM transition here.
 640 // We do it in a helper. This is so we can check to see if the nmethod we have just
 641 // searched for an exception handler has been deoptimized in the meantime.
 642 address Runtime1::exception_handler_for_pc(JavaThread* current) {
 643   oop exception = current->exception_oop();
 644   address pc = current->exception_pc();
 645   // Still in Java mode
 646   DEBUG_ONLY(NoHandleMark nhm);
 647   nmethod* nm = NULL;
 648   address continuation = NULL;
 649   {
 650     // Enter VM mode by calling the helper
 651     ResetNoHandleMark rnhm;
 652     continuation = exception_handler_for_pc_helper(current, exception, pc, nm);
 653   }
 654   // Back in JAVA, use no oops DON'T safepoint
 655 
 656   // Now check to see if the nmethod we were called from is now deoptimized.
 657   // If so we must return to the deopt blob and deoptimize the nmethod
 658   if (nm != NULL && caller_is_deopted(current)) {
 659     continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 660   }
 661 
 662   assert(continuation != NULL, "no handler found");
 663   return continuation;
 664 }
 665 
 666 
 667 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* current, int index, arrayOopDesc* a))
 668 #ifndef PRODUCT
 669   if (PrintC1Statistics) {
 670     _throw_range_check_exception_count++;
 671   }
 672 #endif
 673   const int len = 35;
 674   assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
 675   char message[2 * jintAsStringSize + len];
 676   sprintf(message, "Index %d out of bounds for length %d", index, a->length());
 677   SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
 678 JRT_END
 679 
 680 
 681 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* current, int index))
 682 #ifndef PRODUCT
 683   if (PrintC1Statistics) {
 684     _throw_index_exception_count++;
 685   }
 686 #endif
 687   char message[16];
 688   sprintf(message, "%d", index);
 689   SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
 690 JRT_END
 691 
 692 
 693 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* current))
 694 #ifndef PRODUCT
 695   if (PrintC1Statistics) {
 696     _throw_div0_exception_count++;
 697   }
 698 #endif
 699   SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
 700 JRT_END
 701 
 702 
 703 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* current))
 704 #ifndef PRODUCT
 705   if (PrintC1Statistics) {
 706     _throw_null_pointer_exception_count++;
 707   }
 708 #endif
 709   SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_NullPointerException());
 710 JRT_END
 711 
 712 
 713 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* current, oopDesc* object))
 714 #ifndef PRODUCT
 715   if (PrintC1Statistics) {
 716     _throw_class_cast_exception_count++;
 717   }
 718 #endif
 719   ResourceMark rm(current);
 720   char* message = SharedRuntime::generate_class_cast_message(current, object->klass());
 721   SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ClassCastException(), message);
 722 JRT_END
 723 
 724 
 725 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* current))
 726 #ifndef PRODUCT
 727   if (PrintC1Statistics) {
 728     _throw_incompatible_class_change_error_count++;
 729   }
 730 #endif
 731   ResourceMark rm(current);
 732   SharedRuntime::throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IncompatibleClassChangeError());
 733 JRT_END
 734 
 735 
 736 JRT_BLOCK_ENTRY(void, Runtime1::monitorenter(JavaThread* current, oopDesc* obj, BasicObjectLock* lock))
 737 #ifndef PRODUCT
 738   if (PrintC1Statistics) {
 739     _monitorenter_slowcase_cnt++;
 740   }
 741 #endif
 742   if (!UseFastLocking) {
 743     lock->set_obj(obj);
 744   }
 745   assert(obj == lock->obj(), "must match");
 746   SharedRuntime::monitor_enter_helper(obj, lock->lock(), current);
 747 JRT_END
 748 
 749 
 750 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* current, BasicObjectLock* lock))
 751 #ifndef PRODUCT
 752   if (PrintC1Statistics) {
 753     _monitorexit_slowcase_cnt++;
 754   }
 755 #endif
 756   assert(current->last_Java_sp(), "last_Java_sp must be set");
 757   oop obj = lock->obj();
 758   assert(oopDesc::is_oop(obj), "must be NULL or an object");
 759   SharedRuntime::monitor_exit_helper(obj, lock->lock(), current);
 760 JRT_END
 761 
 762 // Cf. OptoRuntime::deoptimize_caller_frame
 763 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* current, jint trap_request))
 764   // Called from within the owner thread, so no need for safepoint
 765   RegisterMap reg_map(current, false);
 766   frame stub_frame = current->last_frame();
 767   assert(stub_frame.is_runtime_frame(), "Sanity check");
 768   frame caller_frame = stub_frame.sender(&reg_map);
 769   nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
 770   assert(nm != NULL, "Sanity check");
 771   methodHandle method(current, nm->method());
 772   assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
 773   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
 774   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
 775 
 776   if (action == Deoptimization::Action_make_not_entrant) {
 777     if (nm->make_not_entrant()) {
 778       if (reason == Deoptimization::Reason_tenured) {
 779         MethodData* trap_mdo = Deoptimization::get_method_data(current, method, true /*create_if_missing*/);
 780         if (trap_mdo != NULL) {
 781           trap_mdo->inc_tenure_traps();
 782         }
 783       }
 784     }
 785   }
 786 
 787   // Deoptimize the caller frame.
 788   Deoptimization::deoptimize_frame(current, caller_frame.id());
 789   // Return to the now deoptimized frame.
 790 JRT_END
 791 
 792 
 793 #ifndef DEOPTIMIZE_WHEN_PATCHING
 794 
 795 static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
 796   Bytecode_field field_access(caller, bci);
 797   // This can be static or non-static field access
 798   Bytecodes::Code code       = field_access.code();
 799 
 800   // We must load class, initialize class and resolve the field
 801   fieldDescriptor result; // initialize class if needed
 802   constantPoolHandle constants(THREAD, caller->constants());
 803   LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
 804   return result.field_holder();
 805 }
 806 
 807 
 808 //
 809 // This routine patches sites where a class wasn't loaded or
 810 // initialized at the time the code was generated.  It handles
 811 // references to classes, fields and forcing of initialization.  Most
 812 // of the cases are straightforward and involving simply forcing
 813 // resolution of a class, rewriting the instruction stream with the
 814 // needed constant and replacing the call in this function with the
 815 // patched code.  The case for static field is more complicated since
 816 // the thread which is in the process of initializing a class can
 817 // access it's static fields but other threads can't so the code
 818 // either has to deoptimize when this case is detected or execute a
 819 // check that the current thread is the initializing thread.  The
 820 // current
 821 //
 822 // Patches basically look like this:
 823 //
 824 //
 825 // patch_site: jmp patch stub     ;; will be patched
 826 // continue:   ...
 827 //             ...
 828 //             ...
 829 //             ...
 830 //
 831 // They have a stub which looks like this:
 832 //
 833 //             ;; patch body
 834 //             movl <const>, reg           (for class constants)
 835 //        <or> movl [reg1 + <const>], reg  (for field offsets)
 836 //        <or> movl reg, [reg1 + <const>]  (for field offsets)
 837 //             <being_init offset> <bytes to copy> <bytes to skip>
 838 // patch_stub: call Runtime1::patch_code (through a runtime stub)
 839 //             jmp patch_site
 840 //
 841 //
 842 // A normal patch is done by rewriting the patch body, usually a move,
 843 // and then copying it into place over top of the jmp instruction
 844 // being careful to flush caches and doing it in an MP-safe way.  The
 845 // constants following the patch body are used to find various pieces
 846 // of the patch relative to the call site for Runtime1::patch_code.
 847 // The case for getstatic and putstatic is more complicated because
 848 // getstatic and putstatic have special semantics when executing while
 849 // the class is being initialized.  getstatic/putstatic on a class
 850 // which is being_initialized may be executed by the initializing
 851 // thread but other threads have to block when they execute it.  This
 852 // is accomplished in compiled code by executing a test of the current
 853 // thread against the initializing thread of the class.  It's emitted
 854 // as boilerplate in their stub which allows the patched code to be
 855 // executed before it's copied back into the main body of the nmethod.
 856 //
 857 // being_init: get_thread(<tmp reg>
 858 //             cmpl [reg1 + <init_thread_offset>], <tmp reg>
 859 //             jne patch_stub
 860 //             movl [reg1 + <const>], reg  (for field offsets)  <or>
 861 //             movl reg, [reg1 + <const>]  (for field offsets)
 862 //             jmp continue
 863 //             <being_init offset> <bytes to copy> <bytes to skip>
 864 // patch_stub: jmp Runtim1::patch_code (through a runtime stub)
 865 //             jmp patch_site
 866 //
 867 // If the class is being initialized the patch body is rewritten and
 868 // the patch site is rewritten to jump to being_init, instead of
 869 // patch_stub.  Whenever this code is executed it checks the current
 870 // thread against the intializing thread so other threads will enter
 871 // the runtime and end up blocked waiting the class to finish
 872 // initializing inside the calls to resolve_field below.  The
 873 // initializing class will continue on it's way.  Once the class is
 874 // fully_initialized, the intializing_thread of the class becomes
 875 // NULL, so the next thread to execute this code will fail the test,
 876 // call into patch_code and complete the patching process by copying
 877 // the patch body back into the main part of the nmethod and resume
 878 // executing.
 879 
 880 // NB:
 881 //
 882 // Patchable instruction sequences inherently exhibit race conditions,
 883 // where thread A is patching an instruction at the same time thread B
 884 // is executing it.  The algorithms we use ensure that any observation
 885 // that B can make on any intermediate states during A's patching will
 886 // always end up with a correct outcome.  This is easiest if there are
 887 // few or no intermediate states.  (Some inline caches have two
 888 // related instructions that must be patched in tandem.  For those,
 889 // intermediate states seem to be unavoidable, but we will get the
 890 // right answer from all possible observation orders.)
 891 //
 892 // When patching the entry instruction at the head of a method, or a
 893 // linkable call instruction inside of a method, we try very hard to
 894 // use a patch sequence which executes as a single memory transaction.
 895 // This means, in practice, that when thread A patches an instruction,
 896 // it should patch a 32-bit or 64-bit word that somehow overlaps the
 897 // instruction or is contained in it.  We believe that memory hardware
 898 // will never break up such a word write, if it is naturally aligned
 899 // for the word being written.  We also know that some CPUs work very
 900 // hard to create atomic updates even of naturally unaligned words,
 901 // but we don't want to bet the farm on this always working.
 902 //
 903 // Therefore, if there is any chance of a race condition, we try to
 904 // patch only naturally aligned words, as single, full-word writes.
 905 
 906 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* current, Runtime1::StubID stub_id ))
 907 #ifndef PRODUCT
 908   if (PrintC1Statistics) {
 909     _patch_code_slowcase_cnt++;
 910   }
 911 #endif
 912 
 913   ResourceMark rm(current);
 914   RegisterMap reg_map(current, false);
 915   frame runtime_frame = current->last_frame();
 916   frame caller_frame = runtime_frame.sender(&reg_map);
 917 
 918   // last java frame on stack
 919   vframeStream vfst(current, true);
 920   assert(!vfst.at_end(), "Java frame must exist");
 921 
 922   methodHandle caller_method(current, vfst.method());
 923   // Note that caller_method->code() may not be same as caller_code because of OSR's
 924   // Note also that in the presence of inlining it is not guaranteed
 925   // that caller_method() == caller_code->method()
 926 
 927   int bci = vfst.bci();
 928   Bytecodes::Code code = caller_method()->java_code_at(bci);
 929 
 930   // this is used by assertions in the access_field_patching_id
 931   BasicType patch_field_type = T_ILLEGAL;
 932   bool deoptimize_for_volatile = false;
 933   bool deoptimize_for_atomic = false;
 934   int patch_field_offset = -1;
 935   Klass* init_klass = NULL; // klass needed by load_klass_patching code
 936   Klass* load_klass = NULL; // klass needed by load_klass_patching code
 937   Handle mirror(current, NULL);                    // oop needed by load_mirror_patching code
 938   Handle appendix(current, NULL);                  // oop needed by appendix_patching code
 939   bool load_klass_or_mirror_patch_id =
 940     (stub_id == Runtime1::load_klass_patching_id || stub_id == Runtime1::load_mirror_patching_id);
 941 
 942   if (stub_id == Runtime1::access_field_patching_id) {
 943 
 944     Bytecode_field field_access(caller_method, bci);
 945     fieldDescriptor result; // initialize class if needed
 946     Bytecodes::Code code = field_access.code();
 947     constantPoolHandle constants(current, caller_method->constants());
 948     LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
 949     patch_field_offset = result.offset();
 950 
 951     // If we're patching a field which is volatile then at compile it
 952     // must not have been know to be volatile, so the generated code
 953     // isn't correct for a volatile reference.  The nmethod has to be
 954     // deoptimized so that the code can be regenerated correctly.
 955     // This check is only needed for access_field_patching since this
 956     // is the path for patching field offsets.  load_klass is only
 957     // used for patching references to oops which don't need special
 958     // handling in the volatile case.
 959 
 960     deoptimize_for_volatile = result.access_flags().is_volatile();
 961 
 962     // If we are patching a field which should be atomic, then
 963     // the generated code is not correct either, force deoptimizing.
 964     // We need to only cover T_LONG and T_DOUBLE fields, as we can
 965     // break access atomicity only for them.
 966 
 967     // Strictly speaking, the deoptimization on 64-bit platforms
 968     // is unnecessary, and T_LONG stores on 32-bit platforms need
 969     // to be handled by special patching code when AlwaysAtomicAccesses
 970     // becomes product feature. At this point, we are still going
 971     // for the deoptimization for consistency against volatile
 972     // accesses.
 973 
 974     patch_field_type = result.field_type();
 975     deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
 976 
 977   } else if (load_klass_or_mirror_patch_id) {
 978     Klass* k = NULL;
 979     switch (code) {
 980       case Bytecodes::_putstatic:
 981       case Bytecodes::_getstatic:
 982         { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
 983           init_klass = klass;
 984           mirror = Handle(current, klass->java_mirror());
 985         }
 986         break;
 987       case Bytecodes::_new:
 988         { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
 989           k = caller_method->constants()->klass_at(bnew.index(), CHECK);
 990         }
 991         break;
 992       case Bytecodes::_multianewarray:
 993         { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
 994           k = caller_method->constants()->klass_at(mna.index(), CHECK);
 995         }
 996         break;
 997       case Bytecodes::_instanceof:
 998         { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
 999           k = caller_method->constants()->klass_at(io.index(), CHECK);
1000         }
1001         break;
1002       case Bytecodes::_checkcast:
1003         { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
1004           k = caller_method->constants()->klass_at(cc.index(), CHECK);
1005         }
1006         break;
1007       case Bytecodes::_anewarray:
1008         { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
1009           Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
1010           k = ek->array_klass(CHECK);
1011         }
1012         break;
1013       case Bytecodes::_ldc:
1014       case Bytecodes::_ldc_w:
1015         {
1016           Bytecode_loadconstant cc(caller_method, bci);
1017           oop m = cc.resolve_constant(CHECK);
1018           mirror = Handle(current, m);
1019         }
1020         break;
1021       default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
1022     }
1023     load_klass = k;
1024   } else if (stub_id == load_appendix_patching_id) {
1025     Bytecode_invoke bytecode(caller_method, bci);
1026     Bytecodes::Code bc = bytecode.invoke_code();
1027 
1028     CallInfo info;
1029     constantPoolHandle pool(current, caller_method->constants());
1030     int index = bytecode.index();
1031     LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
1032     switch (bc) {
1033       case Bytecodes::_invokehandle: {
1034         int cache_index = ConstantPool::decode_cpcache_index(index, true);
1035         assert(cache_index >= 0 && cache_index < pool->cache()->length(), "unexpected cache index");
1036         ConstantPoolCacheEntry* cpce = pool->cache()->entry_at(cache_index);
1037         cpce->set_method_handle(pool, info);
1038         appendix = Handle(current, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
1039         break;
1040       }
1041       case Bytecodes::_invokedynamic: {
1042         ConstantPoolCacheEntry* cpce = pool->invokedynamic_cp_cache_entry_at(index);
1043         cpce->set_dynamic_call(pool, info);
1044         appendix = Handle(current, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
1045         break;
1046       }
1047       default: fatal("unexpected bytecode for load_appendix_patching_id");
1048     }
1049   } else {
1050     ShouldNotReachHere();
1051   }
1052 
1053   if (deoptimize_for_volatile || deoptimize_for_atomic) {
1054     // At compile time we assumed the field wasn't volatile/atomic but after
1055     // loading it turns out it was volatile/atomic so we have to throw the
1056     // compiled code out and let it be regenerated.
1057     if (TracePatching) {
1058       if (deoptimize_for_volatile) {
1059         tty->print_cr("Deoptimizing for patching volatile field reference");
1060       }
1061       if (deoptimize_for_atomic) {
1062         tty->print_cr("Deoptimizing for patching atomic field reference");
1063       }
1064     }
1065 
1066     // It's possible the nmethod was invalidated in the last
1067     // safepoint, but if it's still alive then make it not_entrant.
1068     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1069     if (nm != NULL) {
1070       nm->make_not_entrant();
1071     }
1072 
1073     Deoptimization::deoptimize_frame(current, caller_frame.id());
1074 
1075     // Return to the now deoptimized frame.
1076   }
1077 
1078   // Now copy code back
1079 
1080   {
1081     MutexLocker ml_patch (current, Patching_lock, Mutex::_no_safepoint_check_flag);
1082     //
1083     // Deoptimization may have happened while we waited for the lock.
1084     // In that case we don't bother to do any patching we just return
1085     // and let the deopt happen
1086     if (!caller_is_deopted(current)) {
1087       NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
1088       address instr_pc = jump->jump_destination();
1089       NativeInstruction* ni = nativeInstruction_at(instr_pc);
1090       if (ni->is_jump() ) {
1091         // the jump has not been patched yet
1092         // The jump destination is slow case and therefore not part of the stubs
1093         // (stubs are only for StaticCalls)
1094 
1095         // format of buffer
1096         //    ....
1097         //    instr byte 0     <-- copy_buff
1098         //    instr byte 1
1099         //    ..
1100         //    instr byte n-1
1101         //      n
1102         //    ....             <-- call destination
1103 
1104         address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
1105         unsigned char* byte_count = (unsigned char*) (stub_location - 1);
1106         unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
1107         unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
1108         address copy_buff = stub_location - *byte_skip - *byte_count;
1109         address being_initialized_entry = stub_location - *being_initialized_entry_offset;
1110         if (TracePatching) {
1111           ttyLocker ttyl;
1112           tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT "  (%s)", Bytecodes::name(code), bci,
1113                         p2i(instr_pc), (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
1114           nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
1115           assert(caller_code != NULL, "nmethod not found");
1116 
1117           // NOTE we use pc() not original_pc() because we already know they are
1118           // identical otherwise we'd have never entered this block of code
1119 
1120           const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
1121           assert(map != NULL, "null check");
1122           map->print();
1123           tty->cr();
1124 
1125           Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1126         }
1127         // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
1128         bool do_patch = true;
1129         if (stub_id == Runtime1::access_field_patching_id) {
1130           // The offset may not be correct if the class was not loaded at code generation time.
1131           // Set it now.
1132           NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
1133           assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1134           assert(patch_field_offset >= 0, "illegal offset");
1135           n_move->add_offset_in_bytes(patch_field_offset);
1136         } else if (load_klass_or_mirror_patch_id) {
1137           // If a getstatic or putstatic is referencing a klass which
1138           // isn't fully initialized, the patch body isn't copied into
1139           // place until initialization is complete.  In this case the
1140           // patch site is setup so that any threads besides the
1141           // initializing thread are forced to come into the VM and
1142           // block.
1143           do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1144                      InstanceKlass::cast(init_klass)->is_initialized();
1145           NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1146           if (jump->jump_destination() == being_initialized_entry) {
1147             assert(do_patch == true, "initialization must be complete at this point");
1148           } else {
1149             // patch the instruction <move reg, klass>
1150             NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1151 
1152             assert(n_copy->data() == 0 ||
1153                    n_copy->data() == (intptr_t)Universe::non_oop_word(),
1154                    "illegal init value");
1155             if (stub_id == Runtime1::load_klass_patching_id) {
1156               assert(load_klass != NULL, "klass not set");
1157               n_copy->set_data((intx) (load_klass));
1158             } else {
1159               assert(mirror() != NULL, "klass not set");
1160               // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1161               n_copy->set_data(cast_from_oop<intx>(mirror()));
1162             }
1163 
1164             if (TracePatching) {
1165               Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1166             }
1167           }
1168         } else if (stub_id == Runtime1::load_appendix_patching_id) {
1169           NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1170           assert(n_copy->data() == 0 ||
1171                  n_copy->data() == (intptr_t)Universe::non_oop_word(),
1172                  "illegal init value");
1173           n_copy->set_data(cast_from_oop<intx>(appendix()));
1174 
1175           if (TracePatching) {
1176             Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1177           }
1178         } else {
1179           ShouldNotReachHere();
1180         }
1181 
1182 #if defined(PPC32)
1183         if (load_klass_or_mirror_patch_id ||
1184             stub_id == Runtime1::load_appendix_patching_id) {
1185           // Update the location in the nmethod with the proper
1186           // metadata.  When the code was generated, a NULL was stuffed
1187           // in the metadata table and that table needs to be update to
1188           // have the right value.  On intel the value is kept
1189           // directly in the instruction instead of in the metadata
1190           // table, so set_data above effectively updated the value.
1191           nmethod* nm = CodeCache::find_nmethod(instr_pc);
1192           assert(nm != NULL, "invalid nmethod_pc");
1193           RelocIterator mds(nm, copy_buff, copy_buff + 1);
1194           bool found = false;
1195           while (mds.next() && !found) {
1196             if (mds.type() == relocInfo::oop_type) {
1197               assert(stub_id == Runtime1::load_mirror_patching_id ||
1198                      stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1199               oop_Relocation* r = mds.oop_reloc();
1200               oop* oop_adr = r->oop_addr();
1201               *oop_adr = stub_id == Runtime1::load_mirror_patching_id ? mirror() : appendix();
1202               r->fix_oop_relocation();
1203               found = true;
1204             } else if (mds.type() == relocInfo::metadata_type) {
1205               assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1206               metadata_Relocation* r = mds.metadata_reloc();
1207               Metadata** metadata_adr = r->metadata_addr();
1208               *metadata_adr = load_klass;
1209               r->fix_metadata_relocation();
1210               found = true;
1211             }
1212           }
1213           assert(found, "the metadata must exist!");
1214         }
1215 #endif
1216         if (do_patch) {
1217           // replace instructions
1218           // first replace the tail, then the call
1219 #ifdef ARM
1220           if((load_klass_or_mirror_patch_id ||
1221               stub_id == Runtime1::load_appendix_patching_id) &&
1222               nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1223             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1224             address addr = NULL;
1225             assert(nm != NULL, "invalid nmethod_pc");
1226             RelocIterator mds(nm, copy_buff, copy_buff + 1);
1227             while (mds.next()) {
1228               if (mds.type() == relocInfo::oop_type) {
1229                 assert(stub_id == Runtime1::load_mirror_patching_id ||
1230                        stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1231                 oop_Relocation* r = mds.oop_reloc();
1232                 addr = (address)r->oop_addr();
1233                 break;
1234               } else if (mds.type() == relocInfo::metadata_type) {
1235                 assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1236                 metadata_Relocation* r = mds.metadata_reloc();
1237                 addr = (address)r->metadata_addr();
1238                 break;
1239               }
1240             }
1241             assert(addr != NULL, "metadata relocation must exist");
1242             copy_buff -= *byte_count;
1243             NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1244             n_copy2->set_pc_relative_offset(addr, instr_pc);
1245           }
1246 #endif
1247 
1248           for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
1249             address ptr = copy_buff + i;
1250             int a_byte = (*ptr) & 0xFF;
1251             address dst = instr_pc + i;
1252             *(unsigned char*)dst = (unsigned char) a_byte;
1253           }
1254           ICache::invalidate_range(instr_pc, *byte_count);
1255           NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1256 
1257           if (load_klass_or_mirror_patch_id ||
1258               stub_id == Runtime1::load_appendix_patching_id) {
1259             relocInfo::relocType rtype =
1260               (stub_id == Runtime1::load_klass_patching_id) ?
1261                                    relocInfo::metadata_type :
1262                                    relocInfo::oop_type;
1263             // update relocInfo to metadata
1264             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1265             assert(nm != NULL, "invalid nmethod_pc");
1266 
1267             // The old patch site is now a move instruction so update
1268             // the reloc info so that it will get updated during
1269             // future GCs.
1270             RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1271             relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1272                                                      relocInfo::none, rtype);
1273 #ifdef PPC32
1274           { address instr_pc2 = instr_pc + NativeMovConstReg::lo_offset;
1275             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1276             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1277                                                      relocInfo::none, rtype);
1278           }
1279 #endif
1280           }
1281 
1282         } else {
1283           ICache::invalidate_range(copy_buff, *byte_count);
1284           NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1285         }
1286       }
1287     }
1288   }
1289 
1290   // If we are patching in a non-perm oop, make sure the nmethod
1291   // is on the right list.
1292   {
1293     MutexLocker ml_code (current, CodeCache_lock, Mutex::_no_safepoint_check_flag);
1294     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1295     guarantee(nm != NULL, "only nmethods can contain non-perm oops");
1296 
1297     // Since we've patched some oops in the nmethod,
1298     // (re)register it with the heap.
1299     Universe::heap()->register_nmethod(nm);
1300   }
1301 JRT_END
1302 
1303 #else // DEOPTIMIZE_WHEN_PATCHING
1304 
1305 void Runtime1::patch_code(JavaThread* current, Runtime1::StubID stub_id) {
1306 #ifndef PRODUCT
1307   if (PrintC1Statistics) {
1308     _patch_code_slowcase_cnt++;
1309   }
1310 #endif
1311 
1312   // Enable WXWrite: the function is called by c1 stub as a runtime function
1313   // (see another implementation above).
1314   MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
1315 
1316   if (TracePatching) {
1317     tty->print_cr("Deoptimizing because patch is needed");
1318   }
1319 
1320   RegisterMap reg_map(current, false);
1321 
1322   frame runtime_frame = current->last_frame();
1323   frame caller_frame = runtime_frame.sender(&reg_map);
1324   assert(caller_frame.is_compiled_frame(), "Wrong frame type");
1325 
1326   // Make sure the nmethod is invalidated, i.e. made not entrant.
1327   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1328   if (nm != NULL) {
1329     nm->make_not_entrant();
1330   }
1331 
1332   Deoptimization::deoptimize_frame(current, caller_frame.id());
1333   // Return to the now deoptimized frame.
1334   postcond(caller_is_deopted(current));
1335 }
1336 
1337 #endif // DEOPTIMIZE_WHEN_PATCHING
1338 
1339 // Entry point for compiled code. We want to patch a nmethod.
1340 // We don't do a normal VM transition here because we want to
1341 // know after the patching is complete and any safepoint(s) are taken
1342 // if the calling nmethod was deoptimized. We do this by calling a
1343 // helper method which does the normal VM transition and when it
1344 // completes we can check for deoptimization. This simplifies the
1345 // assembly code in the cpu directories.
1346 //
1347 int Runtime1::move_klass_patching(JavaThread* current) {
1348 //
1349 // NOTE: we are still in Java
1350 //
1351   debug_only(NoHandleMark nhm;)
1352   {
1353     // Enter VM mode
1354     ResetNoHandleMark rnhm;
1355     patch_code(current, load_klass_patching_id);
1356   }
1357   // Back in JAVA, use no oops DON'T safepoint
1358 
1359   // Return true if calling code is deoptimized
1360 
1361   return caller_is_deopted(current);
1362 }
1363 
1364 int Runtime1::move_mirror_patching(JavaThread* current) {
1365 //
1366 // NOTE: we are still in Java
1367 //
1368   debug_only(NoHandleMark nhm;)
1369   {
1370     // Enter VM mode
1371     ResetNoHandleMark rnhm;
1372     patch_code(current, load_mirror_patching_id);
1373   }
1374   // Back in JAVA, use no oops DON'T safepoint
1375 
1376   // Return true if calling code is deoptimized
1377 
1378   return caller_is_deopted(current);
1379 }
1380 
1381 int Runtime1::move_appendix_patching(JavaThread* current) {
1382 //
1383 // NOTE: we are still in Java
1384 //
1385   debug_only(NoHandleMark nhm;)
1386   {
1387     // Enter VM mode
1388     ResetNoHandleMark rnhm;
1389     patch_code(current, load_appendix_patching_id);
1390   }
1391   // Back in JAVA, use no oops DON'T safepoint
1392 
1393   // Return true if calling code is deoptimized
1394 
1395   return caller_is_deopted(current);
1396 }
1397 
1398 // Entry point for compiled code. We want to patch a nmethod.
1399 // We don't do a normal VM transition here because we want to
1400 // know after the patching is complete and any safepoint(s) are taken
1401 // if the calling nmethod was deoptimized. We do this by calling a
1402 // helper method which does the normal VM transition and when it
1403 // completes we can check for deoptimization. This simplifies the
1404 // assembly code in the cpu directories.
1405 //
1406 int Runtime1::access_field_patching(JavaThread* current) {
1407   //
1408   // NOTE: we are still in Java
1409   //
1410   // Handles created in this function will be deleted by the
1411   // HandleMarkCleaner in the transition to the VM.
1412   NoHandleMark nhm;
1413   {
1414     // Enter VM mode
1415     ResetNoHandleMark rnhm;
1416     patch_code(current, access_field_patching_id);
1417   }
1418   // Back in JAVA, use no oops DON'T safepoint
1419 
1420   // Return true if calling code is deoptimized
1421 
1422   return caller_is_deopted(current);
1423 }
1424 
1425 
1426 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1427   // for now we just print out the block id
1428   tty->print("%d ", block_id);
1429 JRT_END
1430 
1431 
1432 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1433   // had to return int instead of bool, otherwise there may be a mismatch
1434   // between the C calling convention and the Java one.
1435   // e.g., on x86, GCC may clear only %al when returning a bool false, but
1436   // JVM takes the whole %eax as the return value, which may misinterpret
1437   // the return value as a boolean true.
1438 
1439   assert(mirror != NULL, "should null-check on mirror before calling");
1440   Klass* k = java_lang_Class::as_Klass(mirror);
1441   return (k != NULL && obj != NULL && obj->is_a(k)) ? 1 : 0;
1442 JRT_END
1443 
1444 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* current))
1445   ResourceMark rm;
1446 
1447   RegisterMap reg_map(current, false);
1448   frame runtime_frame = current->last_frame();
1449   frame caller_frame = runtime_frame.sender(&reg_map);
1450 
1451   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1452   assert (nm != NULL, "no more nmethod?");
1453   nm->make_not_entrant();
1454 
1455   methodHandle m(current, nm->method());
1456   MethodData* mdo = m->method_data();
1457 
1458   if (mdo == NULL && !HAS_PENDING_EXCEPTION) {
1459     // Build an MDO.  Ignore errors like OutOfMemory;
1460     // that simply means we won't have an MDO to update.
1461     Method::build_interpreter_method_data(m, THREAD);
1462     if (HAS_PENDING_EXCEPTION) {
1463       // Only metaspace OOM is expected. No Java code executed.
1464       assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here");
1465       CLEAR_PENDING_EXCEPTION;
1466     }
1467     mdo = m->method_data();
1468   }
1469 
1470   if (mdo != NULL) {
1471     mdo->inc_trap_count(Deoptimization::Reason_none);
1472   }
1473 
1474   if (TracePredicateFailedTraps) {
1475     stringStream ss1, ss2;
1476     vframeStream vfst(current);
1477     Method* inlinee = vfst.method();
1478     inlinee->print_short_name(&ss1);
1479     m->print_short_name(&ss2);
1480     tty->print_cr("Predicate failed trap in method %s at bci %d inlined in %s at pc " INTPTR_FORMAT, ss1.as_string(), vfst.bci(), ss2.as_string(), p2i(caller_frame.pc()));
1481   }
1482 
1483 
1484   Deoptimization::deoptimize_frame(current, caller_frame.id());
1485 
1486 JRT_END
1487 
1488 #ifndef PRODUCT
1489 void Runtime1::print_statistics() {
1490   tty->print_cr("C1 Runtime statistics:");
1491   tty->print_cr(" _resolve_invoke_virtual_cnt:     %d", SharedRuntime::_resolve_virtual_ctr);
1492   tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %d", SharedRuntime::_resolve_opt_virtual_ctr);
1493   tty->print_cr(" _resolve_invoke_static_cnt:      %d", SharedRuntime::_resolve_static_ctr);
1494   tty->print_cr(" _handle_wrong_method_cnt:        %d", SharedRuntime::_wrong_method_ctr);
1495   tty->print_cr(" _ic_miss_cnt:                    %d", SharedRuntime::_ic_miss_ctr);
1496   tty->print_cr(" _generic_arraycopystub_cnt:      %d", _generic_arraycopystub_cnt);
1497   tty->print_cr(" _byte_arraycopy_cnt:             %d", _byte_arraycopy_stub_cnt);
1498   tty->print_cr(" _short_arraycopy_cnt:            %d", _short_arraycopy_stub_cnt);
1499   tty->print_cr(" _int_arraycopy_cnt:              %d", _int_arraycopy_stub_cnt);
1500   tty->print_cr(" _long_arraycopy_cnt:             %d", _long_arraycopy_stub_cnt);
1501   tty->print_cr(" _oop_arraycopy_cnt:              %d", _oop_arraycopy_stub_cnt);
1502   tty->print_cr(" _arraycopy_slowcase_cnt:         %d", _arraycopy_slowcase_cnt);
1503   tty->print_cr(" _arraycopy_checkcast_cnt:        %d", _arraycopy_checkcast_cnt);
1504   tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%d", _arraycopy_checkcast_attempt_cnt);
1505 
1506   tty->print_cr(" _new_type_array_slowcase_cnt:    %d", _new_type_array_slowcase_cnt);
1507   tty->print_cr(" _new_object_array_slowcase_cnt:  %d", _new_object_array_slowcase_cnt);
1508   tty->print_cr(" _new_instance_slowcase_cnt:      %d", _new_instance_slowcase_cnt);
1509   tty->print_cr(" _new_multi_array_slowcase_cnt:   %d", _new_multi_array_slowcase_cnt);
1510   tty->print_cr(" _monitorenter_slowcase_cnt:      %d", _monitorenter_slowcase_cnt);
1511   tty->print_cr(" _monitorexit_slowcase_cnt:       %d", _monitorexit_slowcase_cnt);
1512   tty->print_cr(" _patch_code_slowcase_cnt:        %d", _patch_code_slowcase_cnt);
1513 
1514   tty->print_cr(" _throw_range_check_exception_count:            %d:", _throw_range_check_exception_count);
1515   tty->print_cr(" _throw_index_exception_count:                  %d:", _throw_index_exception_count);
1516   tty->print_cr(" _throw_div0_exception_count:                   %d:", _throw_div0_exception_count);
1517   tty->print_cr(" _throw_null_pointer_exception_count:           %d:", _throw_null_pointer_exception_count);
1518   tty->print_cr(" _throw_class_cast_exception_count:             %d:", _throw_class_cast_exception_count);
1519   tty->print_cr(" _throw_incompatible_class_change_error_count:  %d:", _throw_incompatible_class_change_error_count);
1520   tty->print_cr(" _throw_count:                                  %d:", _throw_count);
1521 
1522   SharedRuntime::print_ic_miss_histogram();
1523   tty->cr();
1524 }
1525 #endif // PRODUCT