================ @@ -0,0 +1,66 @@ +//===----------------------------------------------------------------------===// +// +// 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 "clang/Tooling/DependencyScanning/ModuleCacheMutexLock.h" + +#include <mutex> + +using namespace clang; +using namespace tooling; +using namespace dependencies; + +namespace { +struct ModuleCacheMutexLockManager : ModuleCacheLockManager { + std::unique_lock<std::shared_mutex> OwningLock; + + ModuleCacheMutexLockManager(std::shared_mutex &Mutex) + : OwningLock(Mutex, std::try_to_lock_t{}) {} + + operator LockResult() const override { + return OwningLock ? LockResult::Owned : LockResult::Shared; + } + + WaitForUnlockResult waitForUnlock() override { + assert(!OwningLock); + std::shared_lock Lock(*OwningLock.mutex()); + return WaitForUnlockResult::Success; + } + + void unsafeRemoveLock() override { + llvm_unreachable("ModuleCacheMutexLockManager cannot remove locks"); + } + + std::string getErrorMessage() const override { + llvm_unreachable("ModuleCacheMutexLockManager cannot fail"); + } +}; + +struct ModuleCacheMutexLock : ModuleCacheLock { + ModuleCacheMutexes &Mutexes; + + ModuleCacheMutexLock(ModuleCacheMutexes &Mutexes) : Mutexes(Mutexes) {} + + void prepareLock(StringRef Filename) override {} + + std::unique_ptr<ModuleCacheLockManager> tryLock(StringRef Filename) override { + auto &Mutex = [&]() -> std::shared_mutex & { + std::lock_guard Lock(Mutexes.Mutex); + auto &Mutex = Mutexes.Map[Filename]; + if (!Mutex) + Mutex = std::make_unique<std::shared_mutex>(); + return *Mutex; + }(); ---------------- Bigcheese wrote:
I don't think you need a lambda here, the only difference in lifetime without it is that the return value will be constructed before unlock. https://github.com/llvm/llvm-project/pull/129751 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
