openjdkjvmti/ti_method.cc

/* Copyright (C) 2016 The Android Open Source Project
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This file implements interfaces from the file jvmti.h. This implementation
 * is licensed under the same terms as the file jvmti.h.  The
 * copyright and license information for the file jvmti.h follows.
 *
 * Copyright (c) 2003, 2011, 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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 "ti_method.h"

#include <initializer_list>
#include <type_traits>
#include <variant>

#include "android-base/macros.h"
#include "arch/context.h"
#include "art_jvmti.h"
#include "art_method-inl.h"
#include "base/enums.h"
#include "base/globals.h"
#include "base/macros.h"
#include "base/mutex-inl.h"
#include "deopt_manager.h"
#include "dex/code_item_accessors-inl.h"
#include "dex/code_item_accessors.h"
#include "dex/dex_file_annotations.h"
#include "dex/dex_file_types.h"
#include "dex/dex_instruction.h"
#include "dex/dex_instruction_iterator.h"
#include "dex/modifiers.h"
#include "dex/primitive.h"
#include "events-inl.h"
#include "gc_root-inl.h"
#include "handle.h"
#include "jit/jit.h"
#include "jni/jni_internal.h"
#include "jvmti.h"
#include "mirror/class-inl.h"
#include "mirror/class_loader.h"
#include "mirror/object-inl.h"
#include "mirror/object_array-inl.h"
#include "nativehelper/scoped_local_ref.h"
#include "oat_file.h"
#include "obj_ptr.h"
#include "runtime.h"
#include "runtime_callbacks.h"
#include "scoped_thread_state_change-inl.h"
#include "scoped_thread_state_change.h"
#include "stack.h"
#include "thread-current-inl.h"
#include "thread.h"
#include "thread_list.h"
#include "ti_logging.h"
#include "ti_stack.h"
#include "ti_thread.h"
#include "ti_phase.h"
#include "verifier/register_line-inl.h"
#include "verifier/reg_type-inl.h"
#include "verifier/method_verifier-inl.h"

namespace openjdkjvmti {

struct TiMethodCallback : public art::MethodCallback {
  void RegisterNativeMethod(art::ArtMethod* method,
                            const void* cur_method,
                            /*out*/void** new_method)
      override REQUIRES_SHARED(art::Locks::mutator_lock_) {
    if (event_handler->IsEventEnabledAnywhere(ArtJvmtiEvent::kNativeMethodBind)) {
      art::Thread* thread = art::Thread::Current();
      art::JNIEnvExt* jnienv = thread->GetJniEnv();
      ScopedLocalRef<jthread> thread_jni(
          jnienv, PhaseUtil::IsLivePhase() ? jnienv->AddLocalReference<jthread>(thread->GetPeer())
                                           : nullptr);
      jmethodID method_id = art::jni::EncodeArtMethod(method);
      art::ScopedThreadSuspension sts(thread, art::ThreadState::kNative);
      event_handler->DispatchEvent<ArtJvmtiEvent::kNativeMethodBind>(
          thread,
          static_cast<JNIEnv*>(jnienv),
          thread_jni.get(),
          method_id,
          const_cast<void*>(cur_method),
          new_method);
    }
  }

  EventHandler* event_handler = nullptr;
};

TiMethodCallback gMethodCallback;

void MethodUtil::Register(EventHandler* handler) {
  gMethodCallback.event_handler = handler;
  art::ScopedThreadStateChange stsc(art::Thread::Current(),
                                    art::ThreadState::kWaitingForDebuggerToAttach);
  art::ScopedSuspendAll ssa("Add method callback");
  art::RuntimeCallbacks* callbacks = art::Runtime::Current()->GetRuntimeCallbacks();
  callbacks->AddMethodCallback(&gMethodCallback);
}

void MethodUtil::Unregister() {
  art::ScopedThreadStateChange stsc(art::Thread::Current(),
                                    art::ThreadState::kWaitingForDebuggerToAttach);
  art::ScopedSuspendAll ssa("Remove method callback");
  art::RuntimeCallbacks* callbacks = art::Runtime::Current()->GetRuntimeCallbacks();
  callbacks->RemoveMethodCallback(&gMethodCallback);
}

jvmtiError MethodUtil::GetBytecodes(jvmtiEnv* env,
                                    jmethodID method,
                                    jint* size_ptr,
                                    unsigned char** bytecode_ptr) {
  if (method == nullptr) {
    return ERR(INVALID_METHODID);
  }
  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);

  if (art_method->IsNative()) {
    return ERR(NATIVE_METHOD);
  }

  if (size_ptr == nullptr || bytecode_ptr == nullptr) {
    return ERR(NULL_POINTER);
  }

  art::ScopedObjectAccess soa(art::Thread::Current());
  art::CodeItemInstructionAccessor accessor(art_method->DexInstructions());
  if (!accessor.HasCodeItem()) {
    *size_ptr = 0;
    *bytecode_ptr = nullptr;
    return OK;
  }
  // 2 bytes per instruction for dex code.
  *size_ptr = accessor.InsnsSizeInCodeUnits() * 2;
  jvmtiError err = env->Allocate(*size_ptr, bytecode_ptr);
  if (err != OK) {
    return err;
  }
  memcpy(*bytecode_ptr, accessor.Insns(), *size_ptr);
  return OK;
}

jvmtiError MethodUtil::GetArgumentsSize(jvmtiEnv* env ATTRIBUTE_UNUSED,
                                        jmethodID method,
                                        jint* size_ptr) {
  if (method == nullptr) {
    return ERR(INVALID_METHODID);
  }
  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);

  if (art_method->IsNative()) {
    return ERR(NATIVE_METHOD);
  }

  if (size_ptr == nullptr) {
    return ERR(NULL_POINTER);
  }

  art::ScopedObjectAccess soa(art::Thread::Current());
  if (art_method->IsProxyMethod() || art_method->IsAbstract()) {
    // Use the shorty.
    art::ArtMethod* base_method = art_method->GetInterfaceMethodIfProxy(art::kRuntimePointerSize);
    size_t arg_count = art::ArtMethod::NumArgRegisters(base_method->GetShorty());
    if (!base_method->IsStatic()) {
      arg_count++;
    }
    *size_ptr = static_cast<jint>(arg_count);
    return ERR(NONE);
  }

  DCHECK(art_method->HasCodeItem());
  DCHECK_NE(art_method->GetCodeItem(), nullptr);
  *size_ptr = art_method->DexInstructionData().InsSize();

  return ERR(NONE);
}

jvmtiError MethodUtil::GetLocalVariableTable(jvmtiEnv* env,
                                             jmethodID method,
                                             jint* entry_count_ptr,
                                             jvmtiLocalVariableEntry** table_ptr) {
  if (method == nullptr) {
    return ERR(INVALID_METHODID);
  }
  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);

  if (art_method->IsNative()) {
    return ERR(NATIVE_METHOD);
  }

  if (entry_count_ptr == nullptr || table_ptr == nullptr) {
    return ERR(NULL_POINTER);
  }

  art::ScopedObjectAccess soa(art::Thread::Current());

  const art::DexFile* const dex_file = art_method->GetDexFile();
  if (dex_file == nullptr) {
    return ERR(ABSENT_INFORMATION);
  }

  // TODO HasCodeItem == false means that the method is abstract (or native, but we check that
  // earlier). We should check what is returned by the RI in this situation since it's not clear
  // what the appropriate return value is from the spec.
  art::CodeItemDebugInfoAccessor accessor(art_method->DexInstructionDebugInfo());
  if (!accessor.HasCodeItem()) {
    return ERR(ABSENT_INFORMATION);
  }

  std::vector<jvmtiLocalVariableEntry> variables;
  jvmtiError err = OK;

  auto release = [&](jint* out_entry_count_ptr, jvmtiLocalVariableEntry** out_table_ptr) {
    jlong table_size = sizeof(jvmtiLocalVariableEntry) * variables.size();
    if (err != OK ||
        (err = env->Allocate(table_size,
                              reinterpret_cast<unsigned char**>(out_table_ptr))) != OK) {
      for (jvmtiLocalVariableEntry& e : variables) {
        env->Deallocate(reinterpret_cast<unsigned char*>(e.name));
        env->Deallocate(reinterpret_cast<unsigned char*>(e.signature));
        env->Deallocate(reinterpret_cast<unsigned char*>(e.generic_signature));
      }
      return err;
    }
    *out_entry_count_ptr = variables.size();
    memcpy(*out_table_ptr, variables.data(), table_size);
    return OK;
  };

  auto visitor = [&](const art::DexFile::LocalInfo& entry) {
    if (err != OK) {
      return;
    }
    JvmtiUniquePtr<char[]> name_str = CopyString(env, entry.name_, &err);
    if (err != OK) {
      return;
    }
    JvmtiUniquePtr<char[]> sig_str = CopyString(env, entry.descriptor_, &err);
    if (err != OK) {
      return;
    }
    JvmtiUniquePtr<char[]> generic_sig_str = CopyString(env, entry.signature_, &err);
    if (err != OK) {
      return;
    }
    variables.push_back({
      .start_location = static_cast<jlocation>(entry.start_address_),
      .length = static_cast<jint>(entry.end_address_ - entry.start_address_),
      .name = name_str.release(),
      .signature = sig_str.release(),
      .generic_signature = generic_sig_str.release(),
      .slot = entry.reg_,
    });
  };

  if (!accessor.DecodeDebugLocalInfo(art_method->IsStatic(),
                                     art_method->GetDexMethodIndex(),
                                     visitor)) {
    // Something went wrong with decoding the debug information. It might as well not be there.
    return ERR(ABSENT_INFORMATION);
  }
  return release(entry_count_ptr, table_ptr);
}

jvmtiError MethodUtil::GetMaxLocals(jvmtiEnv* env ATTRIBUTE_UNUSED,
                                    jmethodID method,
                                    jint* max_ptr) {
  if (method == nullptr) {
    return ERR(INVALID_METHODID);
  }
  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);

  if (art_method->IsNative()) {
    return ERR(NATIVE_METHOD);
  }

  if (max_ptr == nullptr) {
    return ERR(NULL_POINTER);
  }

  art::ScopedObjectAccess soa(art::Thread::Current());
  if (art_method->IsProxyMethod() || art_method->IsAbstract()) {
    // This isn't specified as an error case, so return 0.
    *max_ptr = 0;
    return ERR(NONE);
  }

  DCHECK(art_method->HasCodeItem());
  DCHECK_NE(art_method->GetCodeItem(), nullptr);
  *max_ptr = art_method->DexInstructionData().RegistersSize();

  return ERR(NONE);
}

jvmtiError MethodUtil::GetMethodName(jvmtiEnv* env,
                                     jmethodID method,
                                     char** name_ptr,
                                     char** signature_ptr,
                                     char** generic_ptr) {
  art::ScopedObjectAccess soa(art::Thread::Current());
  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);
  art_method = art_method->GetInterfaceMethodIfProxy(art::kRuntimePointerSize);

  JvmtiUniquePtr<char[]> name_copy;
  if (name_ptr != nullptr) {
    const char* method_name = art_method->GetName();
    if (method_name == nullptr) {
      method_name = "<error>";
    }
    jvmtiError ret;
    name_copy = CopyString(env, method_name, &ret);
    if (name_copy == nullptr) {
      return ret;
    }
    *name_ptr = name_copy.get();
  }

  JvmtiUniquePtr<char[]> signature_copy;
  if (signature_ptr != nullptr) {
    const art::Signature sig = art_method->GetSignature();
    std::string str = sig.ToString();
    jvmtiError ret;
    signature_copy = CopyString(env, str.c_str(), &ret);
    if (signature_copy == nullptr) {
      return ret;
    }
    *signature_ptr = signature_copy.get();
  }

  if (generic_ptr != nullptr) {
    *generic_ptr = nullptr;
    if (!art_method->GetDeclaringClass()->IsProxyClass()) {
      art::ObjPtr<art::mirror::ObjectArray<art::mirror::String>> str_array =
          art::annotations::GetSignatureAnnotationForMethod(art_method);
      if (str_array != nullptr) {
        std::ostringstream oss;
        for (auto str : str_array->Iterate()) {
          oss << str->ToModifiedUtf8();
        }
        std::string output_string = oss.str();
        jvmtiError ret;
        JvmtiUniquePtr<char[]> generic_copy = CopyString(env, output_string.c_str(), &ret);
        if (generic_copy == nullptr) {
          return ret;
        }
        *generic_ptr = generic_copy.release();
      } else if (soa.Self()->IsExceptionPending()) {
        // TODO: Should we report an error here?
        soa.Self()->ClearException();
      }
    }
  }

  // Everything is fine, release the buffers.
  name_copy.release();
  signature_copy.release();

  return ERR(NONE);
}

jvmtiError MethodUtil::GetMethodDeclaringClass(jvmtiEnv* env ATTRIBUTE_UNUSED,
                                               jmethodID method,
                                               jclass* declaring_class_ptr) {
  if (declaring_class_ptr == nullptr) {
    return ERR(NULL_POINTER);
  }

  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);
  // Note: No GetInterfaceMethodIfProxy, we want to actual class.

  art::ScopedObjectAccess soa(art::Thread::Current());
  art::ObjPtr<art::mirror::Class> klass = art_method->GetDeclaringClass();
  *declaring_class_ptr = soa.AddLocalReference<jclass>(klass);

  return ERR(NONE);
}

jvmtiError MethodUtil::GetMethodLocation(jvmtiEnv* env ATTRIBUTE_UNUSED,
                                         jmethodID method,
                                         jlocation* start_location_ptr,
                                         jlocation* end_location_ptr) {
  if (method == nullptr) {
    return ERR(INVALID_METHODID);
  }
  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);

  if (art_method->IsNative()) {
    return ERR(NATIVE_METHOD);
  }

  if (start_location_ptr == nullptr || end_location_ptr == nullptr) {
    return ERR(NULL_POINTER);
  }

  art::ScopedObjectAccess soa(art::Thread::Current());
  if (art_method->IsProxyMethod() || art_method->IsAbstract()) {
    // This isn't specified as an error case, so return -1/-1 as the RI does.
    *start_location_ptr = -1;
    *end_location_ptr = -1;
    return ERR(NONE);
  }

  DCHECK(art_method->HasCodeItem());
  DCHECK_NE(art_method->GetCodeItem(), nullptr);
  *start_location_ptr = 0;
  *end_location_ptr = art_method->DexInstructions().InsnsSizeInCodeUnits() - 1;

  return ERR(NONE);
}

jvmtiError MethodUtil::GetMethodModifiers(jvmtiEnv* env ATTRIBUTE_UNUSED,
                                          jmethodID method,
                                          jint* modifiers_ptr) {
  if (modifiers_ptr == nullptr) {
    return ERR(NULL_POINTER);
  }

  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);
  uint32_t modifiers = art_method->GetAccessFlags();

  // Note: Keep this code in sync with Executable.fixMethodFlags.
  if ((modifiers & art::kAccAbstract) != 0) {
    modifiers &= ~art::kAccNative;
  }
  modifiers &= ~art::kAccSynchronized;
  if ((modifiers & art::kAccDeclaredSynchronized) != 0) {
    modifiers |= art::kAccSynchronized;
  }
  modifiers &= art::kAccJavaFlagsMask;

  *modifiers_ptr = modifiers;
  return ERR(NONE);
}

jvmtiError MethodUtil::GetLineNumberTable(jvmtiEnv* env,
                                          jmethodID method,
                                          jint* entry_count_ptr,
                                          jvmtiLineNumberEntry** table_ptr) {
  if (method == nullptr) {
    return ERR(NULL_POINTER);
  }
  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);
  DCHECK(!art_method->IsRuntimeMethod());

  art::CodeItemDebugInfoAccessor accessor;
  const art::DexFile* dex_file;
  {
    art::ScopedObjectAccess soa(art::Thread::Current());

    if (art_method->IsProxyMethod()) {
      return ERR(ABSENT_INFORMATION);
    }
    if (art_method->IsNative()) {
      return ERR(NATIVE_METHOD);
    }
    if (entry_count_ptr == nullptr || table_ptr == nullptr) {
      return ERR(NULL_POINTER);
    }

    accessor = art::CodeItemDebugInfoAccessor(art_method->DexInstructionDebugInfo());
    dex_file = art_method->GetDexFile();
    DCHECK(accessor.HasCodeItem()) << art_method->PrettyMethod() << " " << dex_file->GetLocation();
  }

  std::vector<jvmtiLineNumberEntry> context;
  bool success = accessor.DecodeDebugPositionInfo([&](const art::DexFile::PositionInfo& entry) {
    context.push_back({static_cast<jlocation>(entry.address_), static_cast<jint>(entry.line_)});
    return false;
  });
  if (!success) {
    return ERR(ABSENT_INFORMATION);
  }

  unsigned char* data;
  jlong mem_size = context.size() * sizeof(jvmtiLineNumberEntry);
  jvmtiError alloc_error = env->Allocate(mem_size, &data);
  if (alloc_error != ERR(NONE)) {
    return alloc_error;
  }
  *table_ptr = reinterpret_cast<jvmtiLineNumberEntry*>(data);
  memcpy(*table_ptr, context.data(), mem_size);
  *entry_count_ptr = static_cast<jint>(context.size());

  return ERR(NONE);
}

template <typename T>
static jvmtiError IsMethodT(jvmtiEnv* env ATTRIBUTE_UNUSED,
                            jmethodID method,
                            T test,
                            jboolean* is_t_ptr) {
  if (method == nullptr) {
    return ERR(INVALID_METHODID);
  }
  if (is_t_ptr == nullptr) {
    return ERR(NULL_POINTER);
  }

  art::ArtMethod* art_method = art::jni::DecodeArtMethod(method);
  *is_t_ptr = test(art_method) ? JNI_TRUE : JNI_FALSE;

  return ERR(NONE);
}

jvmtiError MethodUtil::IsMethodNative(jvmtiEnv* env, jmethodID m, jboolean* is_native_ptr) {
  auto test = [](art::ArtMethod* method) {
    return method->IsNative();
  };
  return IsMethodT(env, m, test, is_native_ptr);
}

jvmtiError MethodUtil::IsMethodObsolete(jvmtiEnv* env, jmethodID m, jboolean* is_obsolete_ptr) {
  auto test = [](art::ArtMethod* method) {
    return method->IsObsolete();
  };
  return IsMethodT(env, m, test, is_obsolete_ptr);
}

jvmtiError MethodUtil::IsMethodSynthetic(jvmtiEnv* env, jmethodID m, jboolean* is_synthetic_ptr) {
  auto test = [](art::ArtMethod* method) {
    return method->IsSynthetic();
  };
  return IsMethodT(env, m, test, is_synthetic_ptr);
}

class CommonLocalVariableClosure : public art::Closure {
 public:
  // The verifier isn't always able to be as specific as the local-variable-table. We can only get
  // 32-bit, 64-bit or reference.
  enum class VerifierPrimitiveType {
    k32BitValue,  // float, int, short, char, boolean, byte
    k64BitValue,  // double, long
    kReferenceValue,  // Object
    kZeroValue,  // null or zero constant. Might be either k32BitValue or kReferenceValue
  };

  using SlotType = std::variant<art::Primitive::Type, VerifierPrimitiveType>;

  CommonLocalVariableClosure(jvmtiEnv* jvmti, jint depth, jint slot)
      : jvmti_(jvmti), result_(ERR(INTERNAL)), depth_(depth), slot_(slot) {}

  void Run(art::Thread* self) override REQUIRES_SHARED(art::Locks::mutator_lock_) {
    art::Locks::mutator_lock_->AssertSharedHeld(art::Thread::Current());
    bool needs_instrument;
    {
      art::ScopedAssertNoThreadSuspension sants("CommonLocalVariableClosure::Run");
      std::unique_ptr<art::Context> context(art::Context::Create());
      FindFrameAtDepthVisitor visitor(self, context.get(), depth_);
      visitor.WalkStack();
      if (!visitor.FoundFrame()) {
        // Must have been a bad depth.
        result_ = ERR(NO_MORE_FRAMES);
        return;
      }
      art::ArtMethod* method = visitor.GetMethod();
      // Native and 'art' proxy methods don't have registers.
      if (method->IsNative() || method->IsProxyMethod()) {
        // TODO It might be useful to fake up support for get at least on proxy frames.
        result_ = ERR(OPAQUE_FRAME);
        return;
      } else if (slot_ >= method->DexInstructionData().RegistersSize() || slot_ < 0) {
        result_ = ERR(INVALID_SLOT);
        return;
      }
      needs_instrument = !visitor.IsShadowFrame();
      uint32_t pc = visitor.GetDexPc(/*abort_on_failure=*/false);
      if (pc == art::dex::kDexNoIndex) {
        // Cannot figure out current PC.
        result_ = ERR(OPAQUE_FRAME);
        return;
      }
      std::string descriptor;
      SlotType slot_type{ art::Primitive::kPrimVoid };
      jvmtiError err = GetSlotType(method, pc, &descriptor, &slot_type);
      if (err != OK) {
        result_ = err;
        return;
      }

      err = GetTypeError(method, slot_type, descriptor);
      if (err != OK) {
        result_ = err;
        return;
      }
      result_ = Execute(method, visitor);
    }
    if (needs_instrument) {
      DeoptManager::Get()->DeoptimizeThread(self);
    }
  }

  virtual jvmtiError GetResult() {
    return result_;
  }

 protected:
  virtual jvmtiError Execute(art::ArtMethod* method, art::StackVisitor& visitor)
      REQUIRES_SHARED(art::Locks::mutator_lock_) = 0;
  virtual jvmtiError GetTypeError(art::ArtMethod* method,
                                  SlotType type,
                                  const std::string& descriptor)
      REQUIRES_SHARED(art::Locks::mutator_lock_)  = 0;

  jvmtiError GetSlotType(art::ArtMethod* method,
                         uint32_t dex_pc,
                         /*out*/std::string* descriptor,
                         /*out*/SlotType* type)
      REQUIRES_SHARED(art::Locks::mutator_lock_);

  jvmtiError InferSlotTypeFromVerifier(art::ArtMethod* method,
                                       uint32_t dex_pc,
                                       /*out*/ std::string* descriptor,
                                       /*out*/ SlotType* type)
      REQUIRES_SHARED(art::Locks::mutator_lock_) {
    std::unique_ptr<art::verifier::MethodVerifier> verifier(
        art::verifier::MethodVerifier::CalculateVerificationInfo(
            art::Thread::Current(),
            method,
            dex_pc));
    if (verifier == nullptr) {
      JVMTI_LOG(WARNING, jvmti_) << "Unable to extract verification information from "
                                 << method->PrettyMethod() << " due to hard verification failures! "
                                 << "How did this method even get loaded!";
      return ERR(INTERNAL);
    }
    art::verifier::RegisterLine* line = verifier->GetRegLine(dex_pc);
    if (line == nullptr) {
      JVMTI_LOG(WARNING, jvmti_) << "Unable to determine register line at dex-pc " << dex_pc
                                 << " for method " << method->PrettyMethod();
      return ERR(OPAQUE_FRAME);
    }
    const art::verifier::RegType& rt = line->GetRegisterType(verifier.get(), slot_);
    if (rt.IsUndefined()) {
      return ERR(INVALID_SLOT);
    } else if (rt.IsNonZeroReferenceTypes() || rt.IsNull()) {
      *descriptor = (rt.HasClass() ? rt.GetDescriptor() : "Ljava/lang/Object;");
      *type = VerifierPrimitiveType::kReferenceValue;
      return OK;
    } else if (rt.IsZero()) {
      *descriptor = "I";
      *type = VerifierPrimitiveType::kZeroValue;
      return OK;
    } else if (rt.IsCategory1Types()) {
      *descriptor = "I";
      *type = VerifierPrimitiveType::k32BitValue;
      return OK;
    } else if (rt.IsCategory2Types() && rt.IsLowHalf()) {
      *descriptor = "J";
      *type = VerifierPrimitiveType::k64BitValue;
      return OK;
    } else {
      // The slot doesn't have a type. Must not be valid here.
      return ERR(INVALID_SLOT);
    }
  }

  constexpr VerifierPrimitiveType SquashType(SlotType t) {
    if (std::holds_alternative<art::Primitive::Type>(t)) {
      switch (std::get<art::Primitive::Type>(t)) {
        // 32-bit primitives
        case art::Primitive::kPrimByte:
        case art::Primitive::kPrimChar:
        case art::Primitive::kPrimInt:
        case art::Primitive::kPrimShort:
        case art::Primitive::kPrimBoolean:
        case art::Primitive::kPrimFloat:
          return VerifierPrimitiveType::k32BitValue;
        // 64-bit primitives
        case art::Primitive::kPrimLong:
        case art::Primitive::kPrimDouble:
          return VerifierPrimitiveType::k64BitValue;
        case art::Primitive::kPrimNot:
          return VerifierPrimitiveType::kReferenceValue;
        case art::Primitive::kPrimVoid:
          LOG(FATAL) << "Got kPrimVoid";
          UNREACHABLE();
      }
    } else {
      return std::get<VerifierPrimitiveType>(t);
    }
  }

  jvmtiEnv* jvmti_;
  jvmtiError result_;
  jint depth_;
  jint slot_;

 private:
  DISALLOW_COPY_AND_ASSIGN(CommonLocalVariableClosure);
};

std::ostream& operator<<(std::ostream& os,
                         CommonLocalVariableClosure::VerifierPrimitiveType state) {
  switch (state) {
    case CommonLocalVariableClosure::VerifierPrimitiveType::k32BitValue:
      return os << "32BitValue";
    case CommonLocalVariableClosure::VerifierPrimitiveType::k64BitValue:
      return os << "64BitValue";
    case CommonLocalVariableClosure::VerifierPrimitiveType::kReferenceValue:
      return os << "ReferenceValue";
    case CommonLocalVariableClosure::VerifierPrimitiveType::kZeroValue:
      return os << "ZeroValue";
  }
}

std::ostream& operator<<(std::ostream& os, CommonLocalVariableClosure::SlotType state) {
  if (std::holds_alternative<art::Primitive::Type>(state)) {
    return os << "Primitive::Type[" << std::get<art::Primitive::Type>(state) << "]";
  } else {
    return os << "VerifierPrimitiveType["
              << std::get<CommonLocalVariableClosure::VerifierPrimitiveType>(state) << "]";
  }
}

jvmtiError CommonLocalVariableClosure::GetSlotType(art::ArtMethod* method,
                                                   uint32_t dex_pc,
                                                   /*out*/ std::string* descriptor,
                                                   /*out*/ SlotType* type) {
  const art::DexFile* dex_file = method->GetDexFile();
  if (dex_file == nullptr) {
    return ERR(OPAQUE_FRAME);
  }
  art::CodeItemDebugInfoAccessor accessor(method->DexInstructionDebugInfo());
  if (!accessor.HasCodeItem()) {
    return ERR(OPAQUE_FRAME);
  }
  bool found = false;
  *type = art::Primitive::kPrimVoid;
  descriptor->clear();
  auto visitor = [&](const art::DexFile::LocalInfo& entry) {
    if (!found && entry.start_address_ <= dex_pc && entry.end_address_ > dex_pc &&
        entry.reg_ == slot_) {
      found = true;
      *type = art::Primitive::GetType(entry.descriptor_[0]);
      *descriptor = entry.descriptor_;
    }
  };
  if (!accessor.DecodeDebugLocalInfo(method->IsStatic(), method->GetDexMethodIndex(), visitor) ||
      !found) {
    // Something went wrong with decoding the debug information. It might as well not be there.
    // Try to find the type with the verifier.
    // TODO This is very slow.
    return InferSlotTypeFromVerifier(method, dex_pc, descriptor, type);
  } else if (art::kIsDebugBuild) {
    std::string type_unused;
    SlotType verifier_type{ art::Primitive::kPrimVoid };
    DCHECK_EQ(InferSlotTypeFromVerifier(method, dex_pc, &type_unused, &verifier_type), OK)
        << method->PrettyMethod() << " failed to verify!";
    if (*type == SlotType{ art::Primitive::kPrimNot }) {
      // We cannot distinguish between a constant 0 and a null reference so we return that it is a
      // 32bit value (Due to the way references are read by the interpreter this is safe even if
      // it's modified, the value will remain null). This is not ideal since it prevents modifying
      // locals in some circumstances but generally is not a big deal (since one can just modify it
      // later once it's been determined to be a reference by a later instruction).
      DCHECK(verifier_type == SlotType { VerifierPrimitiveType::kZeroValue } ||
             verifier_type == SlotType { VerifierPrimitiveType::kReferenceValue })
          << "Verifier disagrees on type of slot! debug: " << *type
          << " verifier: " << verifier_type;
    } else if (verifier_type == SlotType { VerifierPrimitiveType::kZeroValue }) {
      DCHECK(VerifierPrimitiveType::k32BitValue == SquashType(*type) ||
             VerifierPrimitiveType::kReferenceValue == SquashType(*type))
          << "Verifier disagrees on type of slot! debug: " << *type
          << " verifier: " << verifier_type;
    } else {
      DCHECK_EQ(SquashType(verifier_type), SquashType(*type))
          << "Verifier disagrees on type of slot! debug: " << *type
          << " verifier: " << verifier_type;
    }
  }
  return OK;
}

class GetLocalVariableClosure : public CommonLocalVariableClosure {
 public:
  GetLocalVariableClosure(jvmtiEnv* jvmti,
                          jint depth,
                          jint slot,
                          art::Primitive::Type type,
                          jvalue* val)
      : CommonLocalVariableClosure(jvmti, depth, slot),
        type_(type),
        val_(val),
        obj_val_(nullptr) {}

  jvmtiError GetResult() override REQUIRES_SHARED(art::Locks::mutator_lock_) {
    if (result_ == OK && type_ == art::Primitive::kPrimNot) {
      if (obj_val_ == nullptr) {
        val_->l = nullptr;
      } else {
        art::JNIEnvExt* jni = art::Thread::Current()->GetJniEnv();
        val_->l = static_cast<JNIEnv*>(jni)->NewLocalRef(obj_val_);
        jni->DeleteGlobalRef(obj_val_);
        obj_val_ = nullptr;
      }
    }
    return CommonLocalVariableClosure::GetResult();
  }

 protected:
  jvmtiError
  GetTypeError(art::ArtMethod* method, SlotType slot_type, const std::string& descriptor) override
      REQUIRES_SHARED(art::Locks::mutator_lock_) {
    jvmtiError res = GetTypeErrorInner(method, slot_type, descriptor);
    if (res == ERR(TYPE_MISMATCH)) {
      JVMTI_LOG(INFO, jvmti_) << "Unable to Get local variable in slot " << slot_ << ". Expected"
                              << " slot to be of type compatible with " << SlotType { type_ }
                              << " but slot is " << slot_type;
    } else if (res != OK) {
      JVMTI_LOG(INFO, jvmti_) << "Unable to get local variable in slot " << slot_ << ".";
    }
    return res;
  }

  jvmtiError GetTypeErrorInner(art::ArtMethod* method ATTRIBUTE_UNUSED,
                               SlotType slot_type,
                               const std::string& descriptor ATTRIBUTE_UNUSED)
      REQUIRES_SHARED(art::Locks::mutator_lock_) {
    switch (type_) {
      case art::Primitive::kPrimFloat:
      case art::Primitive::kPrimInt: {
        if (std::holds_alternative<VerifierPrimitiveType>(slot_type)) {
          return (slot_type == SlotType { VerifierPrimitiveType::k32BitValue } ||
                  slot_type == SlotType { VerifierPrimitiveType::kZeroValue })
                     ? OK
                     : ERR(TYPE_MISMATCH);
        } else if (type_ == art::Primitive::kPrimFloat ||
                   slot_type == SlotType { art::Primitive::kPrimFloat }) {
          // Check that we are actually a float.
          return (SlotType { type_ } == slot_type) ? OK : ERR(TYPE_MISMATCH);
        } else {
          // Some smaller int type.
          return SquashType(slot_type) == SquashType(SlotType { type_ }) ? OK : ERR(TYPE_MISMATCH);
        }
      }
      case art::Primitive::kPrimLong:
      case art::Primitive::kPrimDouble: {
        // todo
        if (std::holds_alternative<VerifierPrimitiveType>(slot_type)) {
          return (slot_type == SlotType { VerifierPrimitiveType::k64BitValue })
                     ? OK
                     : ERR(TYPE_MISMATCH);
        } else {
          return slot_type == SlotType { type_ } ? OK : ERR(TYPE_MISMATCH);
        }
      }
      case art::Primitive::kPrimNot:
        return (SquashType(slot_type) == VerifierPrimitiveType::kReferenceValue ||
                SquashType(slot_type) == VerifierPrimitiveType::kZeroValue)
                   ? OK
                   : ERR(TYPE_MISMATCH);
      case art::Primitive::kPrimShort:
      case art::Primitive::kPrimChar:
      case art::Primitive::kPrimByte:
      case art::Primitive::kPrimBoolean:
      case art::Primitive::kPrimVoid:
        LOG(FATAL) << "Unexpected primitive type " << slot_type;
        UNREACHABLE();
    }
  }

  jvmtiError Execute(art::ArtMethod* method, art::StackVisitor& visitor)
      override REQUIRES_SHARED(art::Locks::mutator_lock_) {
    switch (type_) {
      case art::Primitive::kPrimNot: {
        uint32_t ptr_val;
        if (!visitor.GetVReg(method,
                             static_cast<uint16_t>(slot_),
                             art::kReferenceVReg,
                             &ptr_val)) {
          return ERR(OPAQUE_FRAME);
        }
        art::ObjPtr<art::mirror::Object> obj(reinterpret_cast<art::mirror::Object*>(ptr_val));
        obj_val_ = art::Runtime::Current()->GetJavaVM()->AddGlobalRef(art::Thread::Current(), obj);
        break;
      }
      case art::Primitive::kPrimInt:
      case art::Primitive::kPrimFloat: {
        if (!visitor.GetVReg(method,
                             static_cast<uint16_t>(slot_),
                             type_ == art::Primitive::kPrimFloat ? art::kFloatVReg : art::kIntVReg,
                             reinterpret_cast<uint32_t*>(&val_->i))) {
          return ERR(OPAQUE_FRAME);
        }
        break;
      }
      case art::Primitive::kPrimDouble:
      case art::Primitive::kPrimLong: {
        auto lo_type = type_ == art::Primitive::kPrimLong ? art::kLongLoVReg : art::kDoubleLoVReg;
        auto high_type = type_ == art::Primitive::kPrimLong ? art::kLongHiVReg : art::kDoubleHiVReg;
        if (!visitor.GetVRegPair(method,
                                 static_cast<uint16_t>(slot_),
                                 lo_type,
                                 high_type,
                                 reinterpret_cast<uint64_t*>(&val_->j))) {
          return ERR(OPAQUE_FRAME);
        }
        break;
      }
      default: {
        LOG(FATAL) << "unexpected register type " << type_;
        UNREACHABLE();
      }
    }
    return OK;
  }

 private:
  art::Primitive::Type type_;
  jvalue* val_;
  // A global reference to the return value. We use the global reference to safely transfer the
  // value between threads.
  jobject obj_val_;
};

jvmtiError MethodUtil::GetLocalVariableGeneric(jvmtiEnv* env,
                                               jthread thread,
                                               jint depth,
                                               jint slot,
                                               art::Primitive::Type type,
                                               jvalue* val) {
  if (depth < 0) {
    return ERR(ILLEGAL_ARGUMENT);
  }
  art::Thread* self = art::Thread::Current();
  art::ScopedObjectAccess soa(self);
  art::Locks::thread_list_lock_->ExclusiveLock(self);
  art::Thread* target = nullptr;
  jvmtiError err = ERR(INTERNAL);
  if (!ThreadUtil::GetAliveNativeThread(thread, soa, &target, &err)) {
    art::Locks::thread_list_lock_->ExclusiveUnlock(self);
    return err;
  }
  GetLocalVariableClosure c(env, depth, slot, type, val);
  // RequestSynchronousCheckpoint releases the thread_list_lock_ as a part of its execution.
  if (!target->RequestSynchronousCheckpoint(&c)) {
    return ERR(THREAD_NOT_ALIVE);
  } else {
    return c.GetResult();
  }
}

class SetLocalVariableClosure : public CommonLocalVariableClosure {
 public:
  SetLocalVariableClosure(jvmtiEnv* jvmti,
                          art::Thread* caller,
                          jint depth,
                          jint slot,
                          art::Primitive::Type type,
                          jvalue val)
      : CommonLocalVariableClosure(jvmti, depth, slot), caller_(caller), type_(type), val_(val) {}

 protected:
  jvmtiError
  GetTypeError(art::ArtMethod* method, SlotType slot_type, const std::string& descriptor) override
      REQUIRES_SHARED(art::Locks::mutator_lock_) {
    jvmtiError res = GetTypeErrorInner(method, slot_type, descriptor);
    if (res != OK) {
      if (res == ERR(TYPE_MISMATCH)) {
        std::ostringstream desc_exp;
        std::ostringstream desc_set;
        if (type_ == art::Primitive::kPrimNot) {
          desc_exp << " (type: " << descriptor << ")";
          art::ObjPtr<art::mirror::Object> new_val(art::Thread::Current()->DecodeJObject(val_.l));
          desc_set << " (type: "
                  << (new_val.IsNull() ? "NULL" : new_val->GetClass()->PrettyDescriptor()) << ")";
        }
        JVMTI_LOG(INFO, jvmti_) << "Unable to Set local variable in slot " << slot_ << ". Expected"
                                << " slot to be of type compatible with " << SlotType{ type_ }
                                << desc_set.str() << " but slot is " << slot_type << desc_exp.str();
      } else {
        JVMTI_LOG(INFO, jvmti_) << "Unable to set local variable in slot " << slot_ << ". "
                                << err_.str();
      }
    }
    return res;
  }

  jvmtiError
  GetTypeErrorInner(art::ArtMethod* method, SlotType slot_type, const std::string& descriptor)
      REQUIRES_SHARED(art::Locks::mutator_lock_) {
    switch (SquashType(SlotType{ type_ })) {
      case VerifierPrimitiveType::k32BitValue: {
        if (slot_type == SlotType{ VerifierPrimitiveType::kZeroValue }) {
          if (val_.i == 0) {
            return OK;
          } else {
            err_ << "Cannot determine if slot " << slot_ << " is a null reference or 32bit "
                 << "constant. Cannot allow writing to slot.";
            return ERR(INTERNAL);
          }
        } else if (SquashType(slot_type) != VerifierPrimitiveType::k32BitValue) {
          return ERR(TYPE_MISMATCH);
        } else if (slot_type == SlotType { VerifierPrimitiveType::k32BitValue } ||
                   slot_type == SlotType { type_ }) {
          return OK;
        } else if (type_ == art::Primitive::kPrimFloat ||
                   slot_type == SlotType { art::Primitive::kPrimFloat }) {
          // we should have hit the get == type_ above
          return ERR(TYPE_MISMATCH);
        } else {
          // Some smaller type then int.
          return OK;
        }
      }
      case VerifierPrimitiveType::k64BitValue: {
        if (slot_type == SlotType { VerifierPrimitiveType::k64BitValue } ||
            slot_type == SlotType { type_ }) {
          return OK;
        } else {
          return ERR(TYPE_MISMATCH);
        }
      }
      case VerifierPrimitiveType::kReferenceValue: {
        if (SquashType(slot_type) != VerifierPrimitiveType::kReferenceValue &&
            SquashType(slot_type) != VerifierPrimitiveType::kZeroValue) {
          return ERR(TYPE_MISMATCH);
        } else if (val_.l == nullptr) {
          return OK;
        } else if (slot_type == SlotType { VerifierPrimitiveType::kZeroValue }) {
          err_ << "Cannot determine if slot " << slot_ << " is a null "
               << "reference or 32bit constant. Cannot allow writing to slot.";
          return ERR(INTERNAL);
        } else {
          art::ClassLinker* cl = art::Runtime::Current()->GetClassLinker();
          art::ObjPtr<art::mirror::Class> set_class = caller_->DecodeJObject(val_.l)->GetClass();
          art::ObjPtr<art::mirror::ClassLoader> loader =
              method->GetDeclaringClass()->GetClassLoader();
          art::ObjPtr<art::mirror::Class> slot_class =
              cl->LookupClass(caller_, descriptor.c_str(), loader);
          DCHECK(!slot_class.IsNull()) << descriptor << " slot: " << slot_type;
          return slot_class->IsAssignableFrom(set_class) ? OK : ERR(TYPE_MISMATCH);
        }
      }
      case VerifierPrimitiveType::kZeroValue: {
        LOG(FATAL) << "Illegal result from SquashType of art::Primitive::Type " << type_;
        UNREACHABLE();
      }
    }
  }

  jvmtiError Execute(art::ArtMethod* method, art::StackVisitor& visitor)
      override REQUIRES_SHARED(art::Locks::mutator_lock_) {
    switch (type_) {
      case art::Primitive::kPrimNot: {
        if (!visitor.SetVRegReference(method,
                                      static_cast<uint16_t>(slot_),
                                      caller_->DecodeJObject(val_.l))) {
          return ERR(OPAQUE_FRAME);
        }
        break;
      }
      case art::Primitive::kPrimInt:
      case art::Primitive::kPrimFloat: {
        if (!visitor.SetVReg(method,
                             static_cast<uint16_t>(slot_),
                             static_cast<uint32_t>(val_.i),
                             type_ == art::Primitive::kPrimFloat ? art::kFloatVReg
                                                                 : art::kIntVReg)) {
          return ERR(OPAQUE_FRAME);
        }
        break;
      }
      case art::Primitive::kPrimDouble:
      case art::Primitive::kPrimLong: {
        auto lo_type = type_ == art::Primitive::kPrimLong ? art::kLongLoVReg : art::kDoubleLoVReg;
        auto high_type = type_ == art::Primitive::kPrimLong ? art::kLongHiVReg : art::kDoubleHiVReg;
        if (!visitor.SetVRegPair(method,
                                 static_cast<uint16_t>(slot_),
                                 static_cast<uint64_t>(val_.j),
                                 lo_type,
                                 high_type)) {
          return ERR(OPAQUE_FRAME);
        }
        break;
      }
      default: {
        LOG(FATAL) << "unexpected register type " << type_;
        UNREACHABLE();
      }
    }
    return OK;
  }

 private:
  art::Thread* caller_;
  art::Primitive::Type type_;
  jvalue val_;
  std::ostringstream err_;
};

jvmtiError MethodUtil::SetLocalVariableGeneric(jvmtiEnv* env,
                                               jthread thread,
                                               jint depth,
                                               jint slot,
                                               art::Primitive::Type type,
                                               jvalue val) {
  if (depth < 0) {
    return ERR(ILLEGAL_ARGUMENT);
  }
  // Make sure that we know not to do any OSR anymore.
  // TODO We should really keep track of this at the Frame granularity.
  DeoptManager::Get()->SetLocalsUpdated();
  art::Thread* self = art::Thread::Current();
  art::ScopedObjectAccess soa(self);
  art::Locks::thread_list_lock_->ExclusiveLock(self);
  art::Thread* target = nullptr;
  jvmtiError err = ERR(INTERNAL);
  if (!ThreadUtil::GetAliveNativeThread(thread, soa, &target, &err)) {
    art::Locks::thread_list_lock_->ExclusiveUnlock(self);
    return err;
  }
  SetLocalVariableClosure c(env, self, depth, slot, type, val);
  // RequestSynchronousCheckpoint releases the thread_list_lock_ as a part of its execution.
  if (!target->RequestSynchronousCheckpoint(&c)) {
    return ERR(THREAD_NOT_ALIVE);
  } else {
    return c.GetResult();
  }
}

class GetLocalInstanceClosure : public art::Closure {
 public:
  explicit GetLocalInstanceClosure(jint depth)
      : result_(ERR(INTERNAL)),
        depth_(depth),
        val_(nullptr) {}

  void Run(art::Thread* self) override REQUIRES(art::Locks::mutator_lock_) {
    art::ScopedAssertNoThreadSuspension sants("GetLocalInstanceClosure::Run");
    art::Locks::mutator_lock_->AssertSharedHeld(art::Thread::Current());
    std::unique_ptr<art::Context> context(art::Context::Create());
    FindFrameAtDepthVisitor visitor(self, context.get(), depth_);
    visitor.WalkStack();
    if (!visitor.FoundFrame()) {
      // Must have been a bad depth.
      result_ = ERR(NO_MORE_FRAMES);
      return;
    }
    result_ = OK;
    val_ = art::GcRoot<art::mirror::Object>(visitor.GetThisObject());
  }

  jvmtiError GetResult(jobject* data_out) REQUIRES_SHARED(art::Locks::mutator_lock_) {
    if (result_ == OK) {
      *data_out = val_.IsNull()
          ? nullptr
          : art::Thread::Current()->GetJniEnv()->AddLocalReference<jobject>(val_.Read());
    }
    return result_;
  }

 private:
  jvmtiError result_;
  jint depth_;
  art::GcRoot<art::mirror::Object> val_;
};

jvmtiError MethodUtil::GetLocalInstance(jvmtiEnv* env ATTRIBUTE_UNUSED,
                                        jthread thread,
                                        jint depth,
                                        jobject* data) {
  if (depth < 0) {
    return ERR(ILLEGAL_ARGUMENT);
  }
  art::Thread* self = art::Thread::Current();
  art::ScopedObjectAccess soa(self);
  art::Locks::thread_list_lock_->ExclusiveLock(self);
  art::Thread* target = nullptr;
  jvmtiError err = ERR(INTERNAL);
  if (!ThreadUtil::GetAliveNativeThread(thread, soa, &target, &err)) {
    art::Locks::thread_list_lock_->ExclusiveUnlock(self);
    return err;
  }
  art::ScopedAssertNoThreadSuspension sants("Performing GetLocalInstance");
  GetLocalInstanceClosure c(depth);
  // RequestSynchronousCheckpoint releases the thread_list_lock_ as a part of its execution.  We
  // need to avoid suspending as we wait for the checkpoint to occur since we are (potentially)
  // transfering a GcRoot across threads.
  if (!target->RequestSynchronousCheckpoint(&c, art::ThreadState::kRunnable)) {
    return ERR(THREAD_NOT_ALIVE);
  } else {
    return c.GetResult(data);
  }
}

#define FOR_JVMTI_JVALUE_TYPES(fn) \
    fn(jint, art::Primitive::kPrimInt, i) \
    fn(jlong, art::Primitive::kPrimLong, j) \
    fn(jfloat, art::Primitive::kPrimFloat, f) \
    fn(jdouble, art::Primitive::kPrimDouble, d) \
    fn(jobject, art::Primitive::kPrimNot, l)

namespace impl {

template<typename T> void WriteJvalue(T, jvalue*);
template<typename T> void ReadJvalue(jvalue, T*);
template<typename T> art::Primitive::Type GetJNIType();

#define JNI_TYPE_CHAR(type, prim, id) \
template<> art::Primitive::Type GetJNIType<type>() { \
  return prim; \
}

FOR_JVMTI_JVALUE_TYPES(JNI_TYPE_CHAR);

#undef JNI_TYPE_CHAR

#define RW_JVALUE(srctype, prim, id) \
    template<> void ReadJvalue<srctype>(jvalue in, std::add_pointer<srctype>::type out) { \
      *out = in.id; \
    } \
    template<> void WriteJvalue<srctype>(srctype in, jvalue* out) { \
      out->id = in; \
    }

FOR_JVMTI_JVALUE_TYPES(RW_JVALUE);

#undef RW_JVALUE

}  // namespace impl

template<typename T>
jvmtiError MethodUtil::SetLocalVariable(jvmtiEnv* env,
                                        jthread thread,
                                        jint depth,
                                        jint slot,
                                        T data) {
  jvalue v = {.j = 0};
  art::Primitive::Type type = impl::GetJNIType<T>();
  impl::WriteJvalue(data, &v);
  return SetLocalVariableGeneric(env, thread, depth, slot, type, v);
}

template<typename T>
jvmtiError MethodUtil::GetLocalVariable(jvmtiEnv* env,
                                        jthread thread,
                                        jint depth,
                                        jint slot,
                                        T* data) {
  if (data == nullptr) {
    return ERR(NULL_POINTER);
  }
  jvalue v = {.j = 0};
  art::Primitive::Type type = impl::GetJNIType<T>();
  jvmtiError err = GetLocalVariableGeneric(env, thread, depth, slot, type, &v);
  if (err != OK) {
    return err;
  } else {
    impl::ReadJvalue(v, data);
    return OK;
  }
}

#define GET_SET_LV(srctype, prim, id) \
    template jvmtiError MethodUtil::GetLocalVariable<srctype>(jvmtiEnv*, \
                                                              jthread, \
                                                              jint, \
                                                              jint, \
                                                              std::add_pointer<srctype>::type); \
    template jvmtiError MethodUtil::SetLocalVariable<srctype>(jvmtiEnv*, \
                                                              jthread, \
                                                              jint, \
                                                              jint, \
                                                              srctype);

FOR_JVMTI_JVALUE_TYPES(GET_SET_LV);

#undef GET_SET_LV

#undef FOR_JVMTI_JVALUE_TYPES

}  // namespace openjdkjvmti