[Support] Move Parallel algorithms from LLD to LLVM.

Differential Revision: https://reviews.llvm.org/D33024

llvm-svn: 302748

2 files changed, 0 insertions, 275 deletions

diff --git a/lld/include/lld/Core/Parallel.h b/lld/include/lld/Core/Parallel.h
deleted file mode 100644
index 20b774112ca..00000000000
--- a/lld/include/lld/Core/Parallel.h
+++ /dev/null
@@ -1,210 +0,0 @@
-//===- lld/Core/Parallel.h - Parallel utilities ---------------------------===//
-//
-//                             The LLVM Linker
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLD_CORE_PARALLEL_H
-#define LLD_CORE_PARALLEL_H
-
-#include "lld/Core/LLVM.h"
-#include "lld/Core/TaskGroup.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/Config/llvm-config.h"
-#include "llvm/Support/MathExtras.h"
-
-#include <algorithm>
-
-#if defined(_MSC_VER) && LLVM_ENABLE_THREADS
-#include <concrt.h>
-#include <ppl.h>
-#endif
-
-namespace lld {
-
-namespace parallel {
-struct sequential_execution_policy {};
-struct parallel_execution_policy {};
-
-template <typename T>
-struct is_execution_policy
-    : public std::integral_constant<
-          bool, llvm::is_one_of<T, sequential_execution_policy,
-                                parallel_execution_policy>::value> {};
-
-constexpr sequential_execution_policy seq{};
-constexpr parallel_execution_policy par{};
-
-namespace detail {
-
-#if LLVM_ENABLE_THREADS
-
-#if defined(_MSC_VER)
-template <class RandomAccessIterator, class Comparator>
-void parallel_sort(RandomAccessIterator Start, RandomAccessIterator End,
-                   const Comparator &Comp) {
-  concurrency::parallel_sort(Start, End, Comp);
-}
-template <class IterTy, class FuncTy>
-void parallel_for_each(IterTy Begin, IterTy End, FuncTy Fn) {
-  concurrency::parallel_for_each(Begin, End, Fn);
-}
-
-template <class IndexTy, class FuncTy>
-void parallel_for_each_n(IndexTy Begin, IndexTy End, FuncTy Fn) {
-  concurrency::parallel_for(Begin, End, Fn);
-}
-
-#else
-const ptrdiff_t MinParallelSize = 1024;
-
-/// \brief Inclusive median.
-template <class RandomAccessIterator, class Comparator>
-RandomAccessIterator medianOf3(RandomAccessIterator Start,
-                               RandomAccessIterator End,
-                               const Comparator &Comp) {
-  RandomAccessIterator Mid = Start + (std::distance(Start, End) / 2);
-  return Comp(*Start, *(End - 1))
-             ? (Comp(*Mid, *(End - 1)) ? (Comp(*Start, *Mid) ? Mid : Start)
-                                       : End - 1)
-             : (Comp(*Mid, *Start) ? (Comp(*(End - 1), *Mid) ? Mid : End - 1)
-                                   : Start);
-}
-
-template <class RandomAccessIterator, class Comparator>
-void parallel_quick_sort(RandomAccessIterator Start, RandomAccessIterator End,
-                         const Comparator &Comp, TaskGroup &TG, size_t Depth) {
-  // Do a sequential sort for small inputs.
-  if (std::distance(Start, End) < detail::MinParallelSize || Depth == 0) {
-    std::sort(Start, End, Comp);
-    return;
-  }
-
-  // Partition.
-  auto Pivot = medianOf3(Start, End, Comp);
-  // Move Pivot to End.
-  std::swap(*(End - 1), *Pivot);
-  Pivot = std::partition(Start, End - 1, [&Comp, End](decltype(*Start) V) {
-    return Comp(V, *(End - 1));
-  });
-  // Move Pivot to middle of partition.
-  std::swap(*Pivot, *(End - 1));
-
-  // Recurse.
-  TG.spawn([=, &Comp, &TG] {
-    parallel_quick_sort(Start, Pivot, Comp, TG, Depth - 1);
-  });
-  parallel_quick_sort(Pivot + 1, End, Comp, TG, Depth - 1);
-}
-
-template <class RandomAccessIterator, class Comparator>
-void parallel_sort(RandomAccessIterator Start, RandomAccessIterator End,
-                   const Comparator &Comp) {
-  TaskGroup TG;
-  parallel_quick_sort(Start, End, Comp, TG,
-                      llvm::Log2_64(std::distance(Start, End)) + 1);
-}
-
-template <class IterTy, class FuncTy>
-void parallel_for_each(IterTy Begin, IterTy End, FuncTy Fn) {
-  // TaskGroup has a relatively high overhead, so we want to reduce
-  // the number of spawn() calls. We'll create up to 1024 tasks here.
-  // (Note that 1024 is an arbitrary number. This code probably needs
-  // improving to take the number of available cores into account.)
-  ptrdiff_t TaskSize = std::distance(Begin, End) / 1024;
-  if (TaskSize == 0)
-    TaskSize = 1;
-
-  TaskGroup TG;
-  while (TaskSize <= std::distance(Begin, End)) {
-    TG.spawn([=, &Fn] { std::for_each(Begin, Begin + TaskSize, Fn); });
-    Begin += TaskSize;
-  }
-  TG.spawn([=, &Fn] { std::for_each(Begin, End, Fn); });
-}
-
-template <class IndexTy, class FuncTy>
-void parallel_for_each_n(IndexTy Begin, IndexTy End, FuncTy Fn) {
-  ptrdiff_t TaskSize = (End - Begin) / 1024;
-  if (TaskSize == 0)
-    TaskSize = 1;
-
-  TaskGroup TG;
-  IndexTy I = Begin;
-  for (; I + TaskSize < End; I += TaskSize) {
-    TG.spawn([=, &Fn] {
-      for (IndexTy J = I, E = I + TaskSize; J != E; ++J)
-        Fn(J);
-    });
-  }
-  TG.spawn([=, &Fn] {
-    for (IndexTy J = I; J < End; ++J)
-      Fn(J);
-  });
-}
-
-#endif
-
-#endif
-
-template <typename Iter>
-using DefComparator =
-    std::less<typename std::iterator_traits<Iter>::value_type>;
-
-} // namespace detail
-
-// sequential algorithm implementations.
-template <class Policy, class RandomAccessIterator,
-          class Comparator = detail::DefComparator<RandomAccessIterator>>
-void sort(Policy policy, RandomAccessIterator Start, RandomAccessIterator End,
-          const Comparator &Comp = Comparator()) {
-  static_assert(is_execution_policy<Policy>::value,
-                "Invalid execution policy!");
-  std::sort(Start, End, Comp);
-}
-
-template <class Policy, class IterTy, class FuncTy>
-void for_each(Policy policy, IterTy Begin, IterTy End, FuncTy Fn) {
-  static_assert(is_execution_policy<Policy>::value,
-                "Invalid execution policy!");
-  std::for_each(Begin, End, Fn);
-}
-
-template <class Policy, class IndexTy, class FuncTy>
-void for_each_n(Policy policy, IndexTy Begin, IndexTy End, FuncTy Fn) {
-  static_assert(is_execution_policy<Policy>::value,
-                "Invalid execution policy!");
-  for (IndexTy I = Begin; I != End; ++I)
-    Fn(I);
-}
-
-// Parallel algorithm implementations, only available when LLVM_ENABLE_THREADS
-// is true.
-#if LLVM_ENABLE_THREADS
-template <class RandomAccessIterator,
-          class Comparator = detail::DefComparator<RandomAccessIterator>>
-void sort(parallel_execution_policy policy, RandomAccessIterator Start,
-          RandomAccessIterator End, const Comparator &Comp = Comparator()) {
-  detail::parallel_sort(Start, End, Comp);
-}
-
-template <class IterTy, class FuncTy>
-void for_each(parallel_execution_policy policy, IterTy Begin, IterTy End,
-              FuncTy Fn) {
-  detail::parallel_for_each(Begin, End, Fn);
-}
-
-template <class IndexTy, class FuncTy>
-void for_each_n(parallel_execution_policy policy, IndexTy Begin, IndexTy End,
-                FuncTy Fn) {
-  detail::parallel_for_each_n(Begin, End, Fn);
-}
-#endif
-
-} // namespace parallel
-} // End namespace lld
-
-#endif // LLD_CORE_PARALLEL_H
diff --git a/lld/include/lld/Core/TaskGroup.h b/lld/include/lld/Core/TaskGroup.h
deleted file mode 100644
index 6cd173ebbbb..00000000000
--- a/lld/include/lld/Core/TaskGroup.h
+++ /dev/null
@@ -1,65 +0,0 @@
-//===- lld/Core/TaskGroup.h - Task Group ----------------------------------===//
-//
-//                             The LLVM Linker
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLD_CORE_TASKGROUP_H
-#define LLD_CORE_TASKGROUP_H
-
-#include "lld/Core/LLVM.h"
-
-#include <condition_variable>
-#include <functional>
-#include <mutex>
-
-namespace lld {
-/// \brief Allows one or more threads to wait on a potentially unknown number of
-///   events.
-///
-/// A latch starts at \p count. inc() increments this, and dec() decrements it.
-/// All calls to sync() will block while the count is not 0.
-///
-/// Calling dec() on a Latch with a count of 0 has undefined behaivor.
-class Latch {
-  uint32_t Count;
-  mutable std::mutex Mutex;
-  mutable std::condition_variable Cond;
-
-public:
-  explicit Latch(uint32_t count = 0) : Count(count) {}
-  ~Latch() { sync(); }
-
-  void inc() {
-    std::unique_lock<std::mutex> lock(Mutex);
-    ++Count;
-  }
-
-  void dec() {
-    std::unique_lock<std::mutex> lock(Mutex);
-    if (--Count == 0)
-      Cond.notify_all();
-  }
-
-  void sync() const {
-    std::unique_lock<std::mutex> lock(Mutex);
-    Cond.wait(lock, [&] { return Count == 0; });
-  }
-};
-
-/// \brief Allows launching a number of tasks and waiting for them to finish
-///   either explicitly via sync() or implicitly on destruction.
-class TaskGroup {
-  Latch L;
-
-public:
-  void spawn(std::function<void()> F);
-
-  void sync() const { L.sync(); }
-};
-}
-
-#endif