src/hotspot/share/runtime/stubRoutines.cpp - master - githubmirror/panama-vector

src/hotspot/share/runtime/stubRoutines.cpp
574 строки22 KB
Andrew Dinn
8388381: appcds/aotClassLinking/AddReads.java fails with assert(stub_id != StubId::NO_STUBID) failed: blob continuation_blob (stub gen) contains no stubs! when run with -XX:-VMContinuations
20 июл 2026, 15:40
20 июл 2026, 15:4087c1807
/*
 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "asm/codeBuffer.hpp"
#include "asm/macroAssembler.inline.hpp"
#include "memory/resourceArea.hpp"
#include "oops/access.inline.hpp"
#include "oops/klass.hpp"
#include "oops/oop.inline.hpp"
#include "prims/vectorSupport.hpp"
#include "runtime/continuation.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/stubRoutines.hpp"
#include "runtime/timerTrace.hpp"
#include "utilities/align.hpp"
#include "utilities/copy.hpp"
#ifdef COMPILER2
#include "opto/runtime.hpp"
#endif

UnsafeMemoryAccess* UnsafeMemoryAccess::_table                  = nullptr;
int UnsafeMemoryAccess::_table_length                           = 0;
int UnsafeMemoryAccess::_table_max_length                       = 0;
address UnsafeMemoryAccess::_common_exit_stub_pc                = nullptr;

// Implementation of StubRoutines - for a description of how to
// declare new blobs, stubs and entries , see stubDefinitions.hpp.

// Define fields used to store blobs

#define DEFINE_STUBGEN_BLOB_FIELD(blob_name)                            \
  BufferBlob* StubRoutines:: STUBGEN_BLOB_FIELD_NAME(blob_name) = nullptr;

STUBGEN_BLOBS_DO(DEFINE_STUBGEN_BLOB_FIELD)

#undef DEFINE_STUBGEN_BLOB_FIELD

// Define fields used to store stubgen stub entries

#define DEFINE_STUBGEN_ENTRY_FIELD(blob_name, stub_name, field_name, getter_name) \
  address StubRoutines:: STUB_FIELD_NAME(field_name) = nullptr;

#define DEFINE_STUBGEN_ENTRY_FIELD_INIT(blob_name, stub_name, field_name, getter_name, init_function) \
  address StubRoutines:: STUB_FIELD_NAME(field_name) = CAST_FROM_FN_PTR(address, init_function);

#define DEFINE_STUBGEN_ENTRY_FIELD_ARRAY(blob_name, stub_name, field_name, getter_name, count) \
  address StubRoutines:: STUB_FIELD_NAME(field_name)[count] = { nullptr };

STUBGEN_ENTRIES_DO(DEFINE_STUBGEN_ENTRY_FIELD, DEFINE_STUBGEN_ENTRY_FIELD_INIT, DEFINE_STUBGEN_ENTRY_FIELD_ARRAY)

#undef DEFINE_STUBGEN_ENTRY_FIELD_ARRAY
#undef DEFINE_STUBGEN_ENTRY_FIELD_INIT
#undef DEFINE_STUBGEN_ENTRY_FIELD

jint    StubRoutines::_verify_oop_count                         = 0;


address StubRoutines::_string_indexof_array[4]   =    { nullptr };

const char* StubRoutines::get_blob_name(BlobId id) {
  assert(StubInfo::is_stubgen(id), "not a stubgen blob %s", StubInfo::name(id));
  return StubInfo::name(id);
}

const char* StubRoutines::get_stub_name(StubId id) {
  assert(StubInfo::is_stubgen(id), "not a stubgen stub %s", StubInfo::name(id));
  return StubInfo::name(id);
}

#ifdef ASSERT
// translate a stub id to an associated blob id while checking that it
// is a stubgen stub

BlobId StubRoutines::stub_to_blob(StubId id) {
  assert(StubInfo::is_stubgen(id), "not a stubgen stub %s", StubInfo::name(id));
  return StubInfo::blob(id);
}

#endif // ASSERT

// Initialization

extern void StubGenerator_generate(CodeBuffer* code, BlobId blob_id, AOTStubData* stub_data); // only interface to generators
void UnsafeMemoryAccess::create_table(int max_size) {
  UnsafeMemoryAccess::_table = new UnsafeMemoryAccess[max_size];
  UnsafeMemoryAccess::_table_max_length = max_size;
}

bool UnsafeMemoryAccess::contains_pc(address pc) {
  assert(UnsafeMemoryAccess::_table != nullptr, "");
  for (int i = 0; i < UnsafeMemoryAccess::_table_length; i++) {
    UnsafeMemoryAccess* entry = &UnsafeMemoryAccess::_table[i];
    if (pc >= entry->start_pc() && pc < entry->end_pc()) {
      return true;
    }
  }
  return false;
}

address UnsafeMemoryAccess::page_error_continue_pc(address pc) {
  assert(UnsafeMemoryAccess::_table != nullptr, "");
  for (int i = 0; i < UnsafeMemoryAccess::_table_length; i++) {
    UnsafeMemoryAccess* entry = &UnsafeMemoryAccess::_table[i];
    if (pc >= entry->start_pc() && pc < entry->end_pc()) {
      return entry->error_exit_pc();
    }
  }
  return nullptr;
}

// Used to retrieve mark regions that lie within a generated stub so
// they can be saved along with the stub and used to reinit the table
// when the stub is reloaded.

void UnsafeMemoryAccess::collect_entries(address range_start, address range_end, GrowableArray<address>& entries)
{
  for (int i = 0; i < _table_length; i++) {
    UnsafeMemoryAccess& e = _table[i];
    assert((e._start_pc != nullptr &&
            e._end_pc != nullptr &&
            e._error_exit_pc != nullptr),
           "search for entries found incomplete table entry");
    if (e._start_pc >= range_start && e._end_pc <= range_end) {
      assert(((e._error_exit_pc >= range_start &&
               e._error_exit_pc <= range_end) ||
              e._error_exit_pc == _common_exit_stub_pc),
             "unexpected error exit pc");
      entries.append(e._start_pc);
      entries.append(e._end_pc);
      // only return an exit pc when it is within the range of the stub
      if (e._error_exit_pc != _common_exit_stub_pc) {
        entries.append(e._error_exit_pc);
      } else {
        // an address outside the stub must be the common exit stub
        // address which is marked with a null address
        entries.append(nullptr);
      }
    }
  }
}

static BufferBlob* initialize_stubs(BlobId blob_id,
                                    int code_size, int max_aligned_stubs,
                                    const char* timer_msg,
                                    const char* buffer_name,
                                    const char* assert_msg) {
  assert(StubInfo::is_stubgen(blob_id), "not a stubgen blob %s", StubInfo::name(blob_id));
  if (blob_id == BlobId::stubgen_continuation_id && !VMContinuations) {
      log_info(stubs)("%s\t not generated:\t VMContinuations is disabled", buffer_name);
    return nullptr;
  }
  ResourceMark rm;
  TraceTime timer(timer_msg, TRACETIME_LOG(Info, startuptime));
  // If we are loading stubs we need to check if we can retrieve a
  // blob and/or an associated archived stub descriptor from the
  // AOTCodeCache. If we are storing stubs we need to create a blob
  // but we still need a stub data descriptor to fill in during
  // generation.
  AOTStubData stub_data(blob_id);
  AOTStubData* stub_data_p = nullptr;
  LogTarget(Info, stubs) lt;

  // we need to track and publish details of stubs in a stubgen blob
  // when we are 1) using stubs from the cache 2) dumping stubs to the
  // cache 3) generating stubs that may be needed by other cache
  // elements.

  if (stub_data.is_open()) {
    stub_data_p = &stub_data;
  }
  if (code_size > 0 && stub_data.is_using()) {
    // try to load the blob and details of its stubs from cache. if
    // that fails we will still generate all necessary stubs
    if (stub_data.load_code_blob()) {
      if (lt.is_enabled()) {
        LogStream ls(lt);
        ls.print_cr("Found blob %s in AOT cache", StubInfo::name(blob_id));
      }
    }
  }

  // Even if we managed to load a blob from the AOT cache we still
  // need to allocate a code blob and associated buffer. The AOT blob
  // may not include all the stubs we need for this runtime.

  // Add extra space for large CodeEntryAlignment
  int size = code_size + CodeEntryAlignment * max_aligned_stubs;
  BufferBlob* stubs_code = BufferBlob::create(buffer_name, size);
  if (stubs_code == nullptr) {
    // The compiler blob may be created late by a C2 compiler thread
    // rather than during normal initialization by the initial thread.
    // In that case we can tolerate an allocation failure because the
    // compiler will have been shut down and we have no need of the
    // blob.
    // TODO: Ideally we would still like to try to use any AOT cached
    // blob here but we don't have a fallback if we find that it is
    // missing stubs we need so for now we exit. This should only
    // happen in cases where we have a very small code cache.
    if (Thread::current()->is_Compiler_thread()) {
      assert(blob_id == BlobId::stubgen_compiler_id, "sanity");
      assert(DelayCompilerStubsGeneration, "sanity");
      log_warning(stubs)("%s\t not generated:\t no space left in CodeCache", buffer_name);
      return nullptr;
    }
    vm_exit_out_of_memory(code_size, OOM_MALLOC_ERROR, "CodeCache: no room for %s", buffer_name);
  }
  CodeBuffer buffer(stubs_code);
  short buffer_locs[20];
  buffer.insts()->initialize_shared_locs((relocInfo*)buffer_locs,
                                         sizeof(buffer_locs)/sizeof(relocInfo));
  StubGenerator_generate(&buffer, blob_id, stub_data_p);
  if (code_size == 0) {
    assert(buffer.insts_size() == 0, "should not write into buffer when bob size declared as 0");
    if (lt.is_enabled()) {
      LogStream ls(lt);
      ls.print_cr("%s\t not generated", buffer_name);
    }
    return nullptr;
  }
  // When new stubs added we need to make sure there is some space left
  // to catch situation when we should increase size again.
  assert(buffer.insts_remaining() > 200,
         "increase %s, code_size: %d, used: %d, free: %d",
         assert_msg, code_size, buffer.total_content_size(), buffer.insts_remaining());

  if (stub_data.is_dumping()) {
    // save the blob and publish the entry addresses
    if (stub_data.store_code_blob(*stubs_code, &buffer)) {
      if (lt.is_enabled()) {
        LogStream ls(lt);
        ls.print_cr("Stored blob '%s' to Startup Code Cache", buffer_name);
      }
    } else {
      if (lt.is_enabled()) {
        LogStream ls(lt);
        ls.print_cr("Failed to store blob '%s' to Startup Code Cache", buffer_name);
      }
    }
  } else if (stub_data.is_open()) {
    // we either loaded some entries or generated new entries so
    // publish all entries
    //
    // TODO - ensure we publish collect and publish the preuniverse
    // stubs but don't try to save them
    AOTCodeCache::publish_stub_addresses(*stubs_code, blob_id, &stub_data);
    if (lt.is_enabled()) {
      LogStream ls(lt);
      ls.print_cr("Republished entries for blob '%s'", buffer_name);
    }
  }

  // close off recording of any further stubgen generation
  if (blob_id == BlobId::stubgen_final_id) {
    AOTCodeCache::set_stubgen_stubs_complete();
  }

  if (lt.is_enabled()) {
    LogStream ls(lt);
    ls.print_cr("%s\t [" INTPTR_FORMAT ", " INTPTR_FORMAT "] used: %d, free: %d",
                buffer_name, p2i(stubs_code->content_begin()), p2i(stubs_code->content_end()),
                buffer.total_content_size(), buffer.insts_remaining());
  }

  return stubs_code;
}

// per blob initializer methods StubRoutines::initialize_xxx_stubs()

#define DEFINE_BLOB_INIT_METHOD(blob_name)                              \
  void StubRoutines::initialize_ ## blob_name ## _stubs() {             \
    if (STUBGEN_BLOB_FIELD_NAME(blob_name) == nullptr) {                \
      BlobId blob_id = BlobId:: JOIN3(stubgen, blob_name, id);          \
      int size = _ ## blob_name ## _code_size;                          \
      int max_aligned_stubs = StubInfo::stub_count(blob_id);            \
      const char* timer_msg = "StubRoutines generation " # blob_name " stubs"; \
      const char* name = "StubRoutines (" # blob_name " stubs)";        \
      const char* assert_msg = "_" # blob_name "_code_size";            \
      STUBGEN_BLOB_FIELD_NAME(blob_name) =                              \
        initialize_stubs(blob_id, size, max_aligned_stubs, timer_msg,   \
                         name, assert_msg);                             \
    }                                                                   \
  }


STUBGEN_BLOBS_DO(DEFINE_BLOB_INIT_METHOD)

#undef DEFINE_BLOB_INIT_METHOD

// external driver API functions for per blob init: xxx_stubs_init()

#define DEFINE_BLOB_INIT_FUNCTION(blob_name)            \
  void blob_name ## _stubs_init()  {                    \
    StubRoutines::initialize_ ## blob_name ## _stubs(); \
  }

STUBGEN_BLOBS_DO(DEFINE_BLOB_INIT_FUNCTION)

#undef DEFINE_BLOB_INIT_FUNCTION


#if INCLUDE_CDS
// non-generated external API init driver function

void stubs_AOTAddressTable_init() { StubRoutines::init_AOTAddressTable(); }
#endif // INCLUDE_CDS

/*
 * we generate the underlying driver function compiler_stubs_init()
 * but this wrapper is needed to perform special handling depending on
 * where the compiler init gets called from. it ought to be possible
 * to remove this at some point and have a determinate ordered init.
 */

void compiler_stubs_init(bool in_compiler_thread) {
  if (in_compiler_thread && DelayCompilerStubsGeneration) {
    // Temporarily revert state of stubs generation because
    // it is called after final_stubs_init() finished
    // during compiler runtime initialization.
    // It is fine because these stubs are only used by
    // compiled code and compiler is not running yet.
    StubCodeDesc::unfreeze();
    StubRoutines::initialize_compiler_stubs();
    StubCodeDesc::freeze();
  } else if (!in_compiler_thread && !DelayCompilerStubsGeneration) {
    StubRoutines::initialize_compiler_stubs();
  }
}

//
// Default versions of arraycopy functions
//

JRT_LEAF(void, StubRoutines::jbyte_copy(jbyte* src, jbyte* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_jbyte_array_copy_ctr++;      // Slow-path byte array copy
#endif // !PRODUCT
  Copy::conjoint_jbytes_atomic(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::jshort_copy(jshort* src, jshort* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_jshort_array_copy_ctr++;     // Slow-path short/char array copy
#endif // !PRODUCT
  Copy::conjoint_jshorts_atomic(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::jint_copy(jint* src, jint* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_jint_array_copy_ctr++;       // Slow-path int/float array copy
#endif // !PRODUCT
  Copy::conjoint_jints_atomic(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::jlong_copy(jlong* src, jlong* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_jlong_array_copy_ctr++;      // Slow-path long/double array copy
#endif // !PRODUCT
  Copy::conjoint_jlongs_atomic(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::oop_copy(oop* src, oop* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_oop_array_copy_ctr++;        // Slow-path oop array copy
#endif // !PRODUCT
  assert(count != 0, "count should be non-zero");
  ArrayAccess<>::oop_arraycopy_raw((HeapWord*)src, (HeapWord*)dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::oop_copy_uninit(oop* src, oop* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_oop_array_copy_ctr++;        // Slow-path oop array copy
#endif // !PRODUCT
  assert(count != 0, "count should be non-zero");
  ArrayAccess<IS_DEST_UNINITIALIZED>::oop_arraycopy_raw((HeapWord*)src, (HeapWord*)dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::arrayof_jbyte_copy(HeapWord* src, HeapWord* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_jbyte_array_copy_ctr++;      // Slow-path byte array copy
#endif // !PRODUCT
  Copy::arrayof_conjoint_jbytes(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::arrayof_jshort_copy(HeapWord* src, HeapWord* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_jshort_array_copy_ctr++;     // Slow-path short/char array copy
#endif // !PRODUCT
  Copy::arrayof_conjoint_jshorts(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::arrayof_jint_copy(HeapWord* src, HeapWord* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_jint_array_copy_ctr++;       // Slow-path int/float array copy
#endif // !PRODUCT
  Copy::arrayof_conjoint_jints(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::arrayof_jlong_copy(HeapWord* src, HeapWord* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_jlong_array_copy_ctr++;       // Slow-path int/float array copy
#endif // !PRODUCT
  Copy::arrayof_conjoint_jlongs(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::arrayof_oop_copy(HeapWord* src, HeapWord* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_oop_array_copy_ctr++;        // Slow-path oop array copy
#endif // !PRODUCT
  assert(count != 0, "count should be non-zero");
  ArrayAccess<ARRAYCOPY_ARRAYOF>::oop_arraycopy_raw(src, dest, count);
JRT_END

JRT_LEAF(void, StubRoutines::arrayof_oop_copy_uninit(HeapWord* src, HeapWord* dest, size_t count))
#ifndef PRODUCT
  SharedRuntime::_oop_array_copy_ctr++;        // Slow-path oop array copy
#endif // !PRODUCT
  assert(count != 0, "count should be non-zero");
  ArrayAccess<ARRAYCOPY_ARRAYOF | IS_DEST_UNINITIALIZED>::oop_arraycopy_raw(src, dest, count);
JRT_END

address StubRoutines::select_fill_function(BasicType t, bool aligned, const char* &name) {
#define RETURN_STUB(xxx_fill) { \
  name = #xxx_fill; \
  return StubRoutines::xxx_fill(); }

  switch (t) {
  case T_BYTE:
  case T_BOOLEAN:
    if (!aligned) RETURN_STUB(jbyte_fill);
    RETURN_STUB(arrayof_jbyte_fill);
  case T_CHAR:
  case T_SHORT:
    if (!aligned) RETURN_STUB(jshort_fill);
    RETURN_STUB(arrayof_jshort_fill);
  case T_INT:
  case T_FLOAT:
    if (!aligned) RETURN_STUB(jint_fill);
    RETURN_STUB(arrayof_jint_fill);
  case T_DOUBLE:
  case T_LONG:
  case T_ARRAY:
  case T_OBJECT:
  case T_NARROWOOP:
  case T_NARROWKLASS:
  case T_ADDRESS:
  case T_VOID:
    // Currently unsupported
    return nullptr;

  default:
    ShouldNotReachHere();
    return nullptr;
  }

#undef RETURN_STUB
}

// constants for computing the copy function
enum {
  COPYFUNC_UNALIGNED = 0,
  COPYFUNC_ALIGNED = 1,                 // src, dest aligned to HeapWordSize
  COPYFUNC_CONJOINT = 0,
  COPYFUNC_DISJOINT = 2                 // src != dest, or transfer can descend
};

// Note:  The condition "disjoint" applies also for overlapping copies
// where an descending copy is permitted (i.e., dest_offset <= src_offset).
address
StubRoutines::select_arraycopy_function(BasicType t, bool aligned, bool disjoint, const char* &name, bool dest_uninitialized) {
  int selector =
    (aligned  ? COPYFUNC_ALIGNED  : COPYFUNC_UNALIGNED) +
    (disjoint ? COPYFUNC_DISJOINT : COPYFUNC_CONJOINT);

#define RETURN_STUB(xxx_arraycopy) { \
  name = #xxx_arraycopy; \
  return StubRoutines::xxx_arraycopy(); }

#define RETURN_STUB_PARM(xxx_arraycopy, parm) { \
  name = parm ? #xxx_arraycopy "_uninit": #xxx_arraycopy; \
  return StubRoutines::xxx_arraycopy(parm); }

  switch (t) {
  case T_BYTE:
  case T_BOOLEAN:
    switch (selector) {
    case COPYFUNC_CONJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB(jbyte_arraycopy);
    case COPYFUNC_CONJOINT | COPYFUNC_ALIGNED:    RETURN_STUB(arrayof_jbyte_arraycopy);
    case COPYFUNC_DISJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB(jbyte_disjoint_arraycopy);
    case COPYFUNC_DISJOINT | COPYFUNC_ALIGNED:    RETURN_STUB(arrayof_jbyte_disjoint_arraycopy);
    }
  case T_CHAR:
  case T_SHORT:
    switch (selector) {
    case COPYFUNC_CONJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB(jshort_arraycopy);
    case COPYFUNC_CONJOINT | COPYFUNC_ALIGNED:    RETURN_STUB(arrayof_jshort_arraycopy);
    case COPYFUNC_DISJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB(jshort_disjoint_arraycopy);
    case COPYFUNC_DISJOINT | COPYFUNC_ALIGNED:    RETURN_STUB(arrayof_jshort_disjoint_arraycopy);
    }
  case T_INT:
  case T_FLOAT:
    switch (selector) {
    case COPYFUNC_CONJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB(jint_arraycopy);
    case COPYFUNC_CONJOINT | COPYFUNC_ALIGNED:    RETURN_STUB(arrayof_jint_arraycopy);
    case COPYFUNC_DISJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB(jint_disjoint_arraycopy);
    case COPYFUNC_DISJOINT | COPYFUNC_ALIGNED:    RETURN_STUB(arrayof_jint_disjoint_arraycopy);
    }
  case T_DOUBLE:
  case T_LONG:
    switch (selector) {
    case COPYFUNC_CONJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB(jlong_arraycopy);
    case COPYFUNC_CONJOINT | COPYFUNC_ALIGNED:    RETURN_STUB(arrayof_jlong_arraycopy);
    case COPYFUNC_DISJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB(jlong_disjoint_arraycopy);
    case COPYFUNC_DISJOINT | COPYFUNC_ALIGNED:    RETURN_STUB(arrayof_jlong_disjoint_arraycopy);
    }
  case T_ARRAY:
  case T_OBJECT:
    switch (selector) {
    case COPYFUNC_CONJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB_PARM(oop_arraycopy, dest_uninitialized);
    case COPYFUNC_CONJOINT | COPYFUNC_ALIGNED:    RETURN_STUB_PARM(arrayof_oop_arraycopy, dest_uninitialized);
    case COPYFUNC_DISJOINT | COPYFUNC_UNALIGNED:  RETURN_STUB_PARM(oop_disjoint_arraycopy, dest_uninitialized);
    case COPYFUNC_DISJOINT | COPYFUNC_ALIGNED:    RETURN_STUB_PARM(arrayof_oop_disjoint_arraycopy, dest_uninitialized);
    }
  default:
    ShouldNotReachHere();
    return nullptr;
  }

#undef RETURN_STUB
#undef RETURN_STUB_PARM
}

UnsafeMemoryAccessMark::UnsafeMemoryAccessMark(StubCodeGenerator* cgen, bool add_entry, bool continue_at_scope_end, address error_exit_pc) {
  _cgen = cgen;
  _ucm_entry = nullptr;
  if (add_entry) {
    address err_exit_pc = nullptr;
    if (!continue_at_scope_end) {
      err_exit_pc = error_exit_pc != nullptr ? error_exit_pc : UnsafeMemoryAccess::common_exit_stub_pc();
    }
    assert(err_exit_pc != nullptr || continue_at_scope_end, "error exit not set");
    _ucm_entry = UnsafeMemoryAccess::add_to_table(_cgen->assembler()->pc(), nullptr, err_exit_pc);
  }
}

UnsafeMemoryAccessMark::~UnsafeMemoryAccessMark() {
  if (_ucm_entry != nullptr) {
    _ucm_entry->set_end_pc(_cgen->assembler()->pc());
    if (_ucm_entry->error_exit_pc() == nullptr) {
      _ucm_entry->set_error_exit_pc(_cgen->assembler()->pc());
    }
  }
}