[llvm-branch-commits] [llvm] [libsycl] Add parallel_for feature (PR #189068)

[Sergey Semenov via llvm-branch-commits]

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@@ -0,0 +1,412 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file contains the declaration of the SYCL 2020 ranges and index space
+/// identifiers (4.9.1.).
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBSYCL___IMPL_INDEX_SPACE_CLASSES_HPP
+#define _LIBSYCL___IMPL_INDEX_SPACE_CLASSES_HPP
+
+#include <sycl/__impl/detail/config.hpp>
+
+#include <cstddef>
+#include <type_traits>
+#include <variant>
+
+_LIBSYCL_BEGIN_NAMESPACE_SYCL
+
+namespace detail {
+
+class Builder;
+
+/// Helper class for dimensions data management.
+template <int Dimensions = 1> class RawArray {
+  static_assert(Dimensions >= 1 && Dimensions <= 3,
+                "RawArray can only be 1, 2, or 3 Dimensional.");
+
+public:
+  /// Constructs one-dimensional instance and assign corresponding data to Dim0
+  /// value. Available only if Dimensions = 1.
+  template <int N = Dimensions, std::enable_if_t<N == 1, bool> = true>
+  RawArray(size_t Dim0 = 0) : MArray{Dim0} {}
+
+  /// Constructs two-dimensional instance and assign corresponding data.
+  /// Available only if Dimensions = 2.
+  template <int N = Dimensions, std::enable_if_t<N == 2, bool> = true>
+  RawArray(size_t Dim0, size_t Dim1) : MArray{Dim0, Dim1} {}
+
+  /// Constructs two-dimensional instance with zero-initialized corresponding
+  /// data. Available only if Dimensions = 2.
+  template <int N = Dimensions, std::enable_if_t<N == 2, bool> = true>
+  RawArray() : RawArray(0, 0) {}
+
+  /// Constructs three-dimensional instance and assign corresponding data.
+  /// Available only if Dimensions = 3.
+  template <int N = Dimensions, std::enable_if_t<N == 3, bool> = true>
+  RawArray(size_t Dim0, size_t Dim1, size_t Dim2) : MArray{Dim0, Dim1, Dim2} {}
+
+  /// Constructs three-dimensional instance with zero-initialized corresponding
+  /// data. Available only if Dimensions = 3.
+  template <int N = Dimensions, std::enable_if_t<N == 3, bool> = true>
+  RawArray() : RawArray(0, 0, 0) {}
+
+  /// Returns value for the specified dimension.
+  /// Results in undefined behavior if dimension is not in the range [0,
+  /// Dimensions).
+  /// \param Dimension a dimension to query data for.
+  /// \return value in array matching requested dimension.
+  std::size_t get(int Dimension) const noexcept { return MArray[Dimension]; }
+
+  /// Returns value for the specified dimension.
+  /// Results in undefined behavior if dimension is not in the range [0,
+  /// Dimensions).
+  /// \param Dimension a dimension to query data for.
+  /// \return value in array matching requested dimension.
+  std::size_t &operator[](int Dimension) noexcept { return MArray[Dimension]; }
+
+  /// Returns value for the specified dimension.
+  /// Results in undefined behavior if dimension is not in the range [0,
+  /// Dimensions).
+  /// \param Dimension a dimension to query data for.
+  /// \return value in array matching requested dimension.
+  std::size_t operator[](int Dimension) const noexcept {
+    return MArray[Dimension];
+  }
+
+  RawArray(const RawArray<Dimensions> &rhs) = default;
+  RawArray(RawArray<Dimensions> &&rhs) = default;
+  RawArray<Dimensions> &operator=(const RawArray<Dimensions> &rhs) = default;
+  RawArray<Dimensions> &operator=(RawArray<Dimensions> &&rhs) = default;
+  ~RawArray() = default;
+
+  friend bool operator==(const RawArray<Dimensions> &lhs,
+                         const RawArray<Dimensions> &rhs) {
+    for (int i = 0; i < Dimensions; ++i) {
+      if (lhs.MArray[i] != rhs.MArray[i]) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  friend bool operator!=(const RawArray<Dimensions> &lhs,
+                         const RawArray<Dimensions> &rhs) {
+    return !(lhs == rhs);
+  }
+
+protected:
+  size_t MArray[Dimensions];
+};
+} // namespace detail
+
+/// SYCL 2020 4.9.1.1. range class.
+/// range<int Dimensions> is a 1D, 2D or 3D vector that defines the iteration
+/// domain of either a single work-group in a parallel dispatch, or the overall
+/// Dimensions of the dispatch.
+template <int Dimensions = 1>
+class range : public detail::RawArray<Dimensions> {
+  static_assert(Dimensions >= 1 && Dimensions <= 3,
+                "range can only be 1, 2, or 3 Dimensional.");
+  using Base = detail::RawArray<Dimensions>;
+
+public:
+  static constexpr int dimensions = Dimensions;
+  range() noexcept = default;
+  range(const range<Dimensions> &rhs) = default;
+  range(range<Dimensions> &&rhs) = default;
+  range<Dimensions> &operator=(const range<Dimensions> &rhs) = default;
+  range<Dimensions> &operator=(range<Dimensions> &&rhs) = default;
+
+  /// Construct a 1D range with value dim0.
----------------
sergey-semenov wrote:

```suggestion
  /// Constructs a 1D range with value dim0.
```
The same applies below.

https://github.com/llvm/llvm-project/pull/189068