[Support] Base RWMutex on std::shared_timed_mutex (C++14)

This should have the same semantics. We use std::shared_mutex instead on
MSVC and C++17, std::shared_timed_mutex is less efficient than our
custom implementation on Windows, std::shared_mutex should be faster.

llvm-svn: 369018

1 files changed, 0 insertions, 50 deletions

diff --git a/llvm/lib/Support/Unix/RWMutex.inc b/llvm/lib/Support/Unix/RWMutex.inc
deleted file mode 100644
index 8b47dfa0f85..00000000000
--- a/llvm/lib/Support/Unix/RWMutex.inc
+++ /dev/null
@@ -1,50 +0,0 @@
-//= llvm/Support/Unix/RWMutex.inc - Unix Reader/Writer Mutual Exclusion Lock  =//
-//
-// 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
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements the Unix specific (non-pthread) RWMutex class.
-//
-//===----------------------------------------------------------------------===//
-
-//===----------------------------------------------------------------------===//
-//=== WARNING: Implementation here must contain only generic UNIX code that
-//===          is guaranteed to work on *all* UNIX variants.
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Support/Mutex.h"
-
-namespace llvm {
-
-using namespace sys;
-
-// This naive implementation treats readers the same as writers.  This
-// will therefore deadlock if a thread tries to acquire a read lock
-// multiple times.
-
-RWMutexImpl::RWMutexImpl() : data_(new MutexImpl(false)) { }
-
-RWMutexImpl::~RWMutexImpl() {
-  delete static_cast<MutexImpl *>(data_);
-}
-
-bool RWMutexImpl::reader_acquire() {
-  return static_cast<MutexImpl *>(data_)->acquire();
-}
-
-bool RWMutexImpl::reader_release() {
-  return static_cast<MutexImpl *>(data_)->release();
-}
-
-bool RWMutexImpl::writer_acquire() {
-  return static_cast<MutexImpl *>(data_)->acquire();
-}
-
-bool RWMutexImpl::writer_release() {
-  return static_cast<MutexImpl *>(data_)->release();
-}
-
-}