Add OpenMP support

third_party/openmp/ompx.h

@@ -0,0 +1,165 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __OMPX_H
+#define __OMPX_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int omp_get_ancestor_thread_num(int);
+int omp_get_team_size(int);
+
+#ifdef __cplusplus
+}
+#endif
+
+/// Target kernel language extensions
+///
+/// These extensions exist for the host to allow fallback implementations,
+/// however, they cannot be arbitrarily composed with OpenMP. If the rules of
+/// the kernel language are followed, the host fallbacks should behave as
+/// expected since the kernel is represented as 3 sequential outer loops, one
+/// for each grid dimension, and three (nested) parallel loops, one for each
+/// block dimension. This fallback is not supposed to be optimal and should be
+/// configurable by the user.
+///
+///{
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum {
+  ompx_relaxed = __ATOMIC_RELAXED,
+  ompx_aquire = __ATOMIC_ACQUIRE,
+  ompx_release = __ATOMIC_RELEASE,
+  ompx_acq_rel = __ATOMIC_ACQ_REL,
+  ompx_seq_cst = __ATOMIC_SEQ_CST,
+};
+
+enum {
+  ompx_dim_x = 0,
+  ompx_dim_y = 1,
+  ompx_dim_z = 2,
+};
+
+/// ompx_{thread,block}_{id,dim}
+///{
+#pragma omp begin declare variant match(device = {kind(cpu)})
+#define _TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_C(NAME, VALUE)                     \
+  static inline int ompx_##NAME(int Dim) { return VALUE; }
+
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_C(thread_id,
+                                      omp_get_ancestor_thread_num(Dim + 1))
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_C(block_dim, omp_get_team_size(Dim + 1))
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_C(block_id, 0)
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_C(grid_dim, 1)
+#undef _TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_C
+///}
+
+/// ompx_{sync_block}_{,divergent}
+///{
+#define _TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_C(RETTY, NAME, ARGS, BODY)         \
+  static inline RETTY ompx_##NAME(ARGS) { BODY; }
+
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_C(void, sync_block, int Ordering,
+                                      _Pragma("omp barrier"));
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_C(void, sync_block_acq_rel, void,
+                                      ompx_sync_block(ompx_acq_rel));
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_C(void, sync_block_divergent, int Ordering,
+                                      ompx_sync_block(Ordering));
+#undef _TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_C
+///}
+
+#pragma omp end declare variant
+
+/// ompx_{sync_block}_{,divergent}
+///{
+#define _TGT_KERNEL_LANGUAGE_DECL_SYNC_C(RETTY, NAME, ARGS)         \
+  RETTY ompx_##NAME(ARGS);
+
+_TGT_KERNEL_LANGUAGE_DECL_SYNC_C(void, sync_block, int Ordering);
+_TGT_KERNEL_LANGUAGE_DECL_SYNC_C(void, sync_block_acq_rel, void);
+_TGT_KERNEL_LANGUAGE_DECL_SYNC_C(void, sync_block_divergent, int Ordering);
+#undef _TGT_KERNEL_LANGUAGE_DECL_SYNC_C
+///}
+
+/// ompx_{thread,block}_{id,dim}_{x,y,z}
+///{
+#define _TGT_KERNEL_LANGUAGE_DECL_GRID_C(NAME)                                 \
+  int ompx_##NAME(int Dim);                                                    \
+  static inline int ompx_##NAME##_x() { return ompx_##NAME(ompx_dim_x); }      \
+  static inline int ompx_##NAME##_y() { return ompx_##NAME(ompx_dim_y); }      \
+  static inline int ompx_##NAME##_z() { return ompx_##NAME(ompx_dim_z); }
+
+_TGT_KERNEL_LANGUAGE_DECL_GRID_C(thread_id)
+_TGT_KERNEL_LANGUAGE_DECL_GRID_C(block_dim)
+_TGT_KERNEL_LANGUAGE_DECL_GRID_C(block_id)
+_TGT_KERNEL_LANGUAGE_DECL_GRID_C(grid_dim)
+#undef _TGT_KERNEL_LANGUAGE_DECL_GRID_C
+///}
+
+#ifdef __cplusplus
+}
+#endif
+
+#ifdef __cplusplus
+
+namespace ompx {
+
+enum {
+  dim_x = ompx_dim_x,
+  dim_y = ompx_dim_y,
+  dim_z = ompx_dim_z,
+};
+
+enum {
+  relaxed = ompx_relaxed ,
+  aquire = ompx_aquire,
+  release = ompx_release,
+  acc_rel = ompx_acq_rel,
+  seq_cst = ompx_seq_cst,
+};
+
+/// ompx::{thread,block}_{id,dim}_{,x,y,z}
+///{
+#define _TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_CXX(NAME)                          \
+  static inline int NAME(int Dim) noexcept { return ompx_##NAME(Dim); }        \
+  static inline int NAME##_x() noexcept { return NAME(ompx_dim_x); }           \
+  static inline int NAME##_y() noexcept { return NAME(ompx_dim_y); }           \
+  static inline int NAME##_z() noexcept { return NAME(ompx_dim_z); }
+
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_CXX(thread_id)
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_CXX(block_dim)
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_CXX(block_id)
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_CXX(grid_dim)
+#undef _TGT_KERNEL_LANGUAGE_HOST_IMPL_GRID_CXX
+///}
+
+/// ompx_{sync_block}_{,divergent}
+///{
+#define _TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_CXX(RETTY, NAME, ARGS, CALL_ARGS)  \
+  static inline RETTY NAME(ARGS) {               \
+    return ompx_##NAME(CALL_ARGS);                                             \
+  }
+
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_CXX(void, sync_block, int Ordering = acc_rel,
+                                        Ordering);
+_TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_CXX(void, sync_block_divergent,
+                                        int Ordering = acc_rel, Ordering);
+#undef _TGT_KERNEL_LANGUAGE_HOST_IMPL_SYNC_CXX
+///}
+
+} // namespace ompx
+#endif
+
+///}
+
+#endif /* __OMPX_H */