//===------- EPCGenericDylibManager.cpp -- Dylib management via EPC -------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "llvm/ExecutionEngine/Orc/EPCGenericDylibManager.h"

#include "llvm/ExecutionEngine/Orc/Core.h"
#include "llvm/ExecutionEngine/Orc/Shared/OrcRTBridge.h"
#include "llvm/ExecutionEngine/Orc/Shared/SimpleRemoteEPCUtils.h"

namespace llvm {
namespace orc {
namespace shared {

template <>
class SPSSerializationTraits<SPSRemoteSymbolLookupSetElement,
                             SymbolLookupSet::value_type> {
public:
  static size_t size(const SymbolLookupSet::value_type &V) {
    return SPSArgList<SPSString, bool>::size(
        *V.first, V.second == SymbolLookupFlags::RequiredSymbol);
  }

  static bool serialize(SPSOutputBuffer &OB,
                        const SymbolLookupSet::value_type &V) {
    return SPSArgList<SPSString, bool>::serialize(
        OB, *V.first, V.second == SymbolLookupFlags::RequiredSymbol);
  }
};

template <>
class TrivialSPSSequenceSerialization<SPSRemoteSymbolLookupSetElement,
                                      SymbolLookupSet> {
public:
  static constexpr bool available = true;
};

template <>
class SPSSerializationTraits<SPSRemoteSymbolLookup,
                             DylibManager::LookupRequest> {
  using MemberSerialization =
      SPSArgList<SPSExecutorAddr, SPSRemoteSymbolLookupSet>;

public:
  static size_t size(const DylibManager::LookupRequest &LR) {
    return MemberSerialization::size(ExecutorAddr(LR.Handle), LR.Symbols);
  }

  static bool serialize(SPSOutputBuffer &OB,
                        const DylibManager::LookupRequest &LR) {
    return MemberSerialization::serialize(OB, ExecutorAddr(LR.Handle),
                                          LR.Symbols);
  }
};

} // end namespace shared

Expected<EPCGenericDylibManager>
EPCGenericDylibManager::CreateWithDefaultBootstrapSymbols(
    ExecutorProcessControl &EPC) {
  SymbolAddrs SAs;
  if (auto Err = EPC.getBootstrapSymbols(
          {{SAs.Instance, rt::SimpleExecutorDylibManagerInstanceName},
           {SAs.Open, rt::SimpleExecutorDylibManagerOpenWrapperName},
           {SAs.Resolve, rt::SimpleExecutorDylibManagerResolveWrapperName}}))
    return std::move(Err);
  return EPCGenericDylibManager(EPC, std::move(SAs));
}

Expected<tpctypes::DylibHandle> EPCGenericDylibManager::open(StringRef Path,
                                                             uint64_t Mode) {
  Expected<tpctypes::DylibHandle> H((ExecutorAddr()));
  if (auto Err =
          EPC.callSPSWrapper<rt::SPSSimpleExecutorDylibManagerOpenSignature>(
              SAs.Open, H, SAs.Instance, Path, Mode))
    return std::move(Err);
  return H;
}

void EPCGenericDylibManager::lookupAsync(tpctypes::DylibHandle H,
                                         const SymbolLookupSet &Lookup,
                                         SymbolLookupCompleteFn Complete) {
  EPC.callSPSWrapperAsync<rt::SPSSimpleExecutorDylibManagerResolveSignature>(
      SAs.Resolve,
      [Complete = std::move(Complete)](
          Error SerializationErr,
          Expected<std::vector<std::optional<ExecutorSymbolDef>>>
              Result) mutable {
        if (SerializationErr) {
          cantFail(Result.takeError());
          Complete(std::move(SerializationErr));
          return;
        }
        Complete(std::move(Result));
      },
      H, Lookup);
}

void EPCGenericDylibManager::lookupAsync(tpctypes::DylibHandle H,
                                         const RemoteSymbolLookupSet &Lookup,
                                         SymbolLookupCompleteFn Complete) {
  EPC.callSPSWrapperAsync<rt::SPSSimpleExecutorDylibManagerResolveSignature>(
      SAs.Resolve,
      [Complete = std::move(Complete)](
          Error SerializationErr,
          Expected<std::vector<std::optional<ExecutorSymbolDef>>>
              Result) mutable {
        if (SerializationErr) {
          cantFail(Result.takeError());
          Complete(std::move(SerializationErr));
          return;
        }
        Complete(std::move(Result));
      },
      H, Lookup);
}

Expected<tpctypes::DylibHandle>
EPCGenericDylibManager::loadDylib(const char *DylibPath) {
  return open(DylibPath, 0);
}

/// Async helper to chain together calls to lookupAsync to fulfill all
/// the requests.
/// FIXME: The dylib manager should support multiple LookupRequests natively.
static void
lookupSymbolsAsyncHelper(EPCGenericDylibManager &DylibMgr,
                         ArrayRef<DylibManager::LookupRequest> Request,
                         std::vector<tpctypes::LookupResult> Result,
                         DylibManager::SymbolLookupCompleteFn Complete) {
  if (Request.empty())
    return Complete(std::move(Result));

  auto &Element = Request.front();
  DylibMgr.lookupAsync(Element.Handle, Element.Symbols,
                       [&DylibMgr, Request, Complete = std::move(Complete),
                        Result = std::move(Result)](auto R) mutable {
                         if (!R)
                           return Complete(R.takeError());
                         Result.push_back({});
                         Result.back().reserve(R->size());
                         llvm::append_range(Result.back(), *R);

                         lookupSymbolsAsyncHelper(
                             DylibMgr, Request.drop_front(), std::move(Result),
                             std::move(Complete));
                       });
}

void EPCGenericDylibManager::lookupSymbolsAsync(
    ArrayRef<DylibManager::LookupRequest> Request,
    DylibManager::SymbolLookupCompleteFn Complete) {
  lookupSymbolsAsyncHelper(*this, Request, {}, std::move(Complete));
}

} // end namespace orc
} // end namespace llvm