1 files changed, 47 insertions, 0 deletions
diff --git a/lib/Headers/openmp_wrappers/__clang_openmp_math.h b/lib/Headers/openmp_wrappers/__clang_openmp_math.h
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+++ b/lib/Headers/openmp_wrappers/__clang_openmp_math.h
@@ -0,0 +1,47 @@
+/*===---- __clang_openmp_math.h - OpenMP target math support ---------------===
+ *
+ * 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
+ *
+ *===-----------------------------------------------------------------------===
+ */
+
+#if defined(__NVPTX__) && defined(_OPENMP)
+/// TODO:
+/// We are currently reusing the functionality of the Clang-CUDA code path
+/// as an alternative to the host declarations provided by math.h and cmath.
+/// This is suboptimal.
+///
+/// We should instead declare the device functions in a similar way, e.g.,
+/// through OpenMP 5.0 variants, and afterwards populate the module with the
+/// host declarations by unconditionally including the host math.h or cmath,
+/// respectively. This is actually what the Clang-CUDA code path does, using
+/// __device__ instead of variants to avoid redeclarations and get the desired
+/// overload resolution.
+
+#define __CUDA__
+
+#if defined(__cplusplus)
+  #include <__clang_cuda_math_forward_declares.h>
+  #include <stdlib.h>
+#else
+  #include <stddef.h>
+#endif
+
+/// Include declarations for libdevice functions.
+#include <__clang_cuda_libdevice_declares.h>
+/// Provide definitions for these functions.
+#include <__clang_cuda_device_functions.h>
+
+#if defined(__cplusplus)
+  #include <__clang_cuda_cmath.h>
+#endif
+
+#undef __CUDA__
+
+/// Magic macro for stopping the math.h/cmath host header from being included.
+#define __CLANG_NO_HOST_MATH__
+
+#endif
+