[clang] [libc] [Clang] Implement resource directory headers for common GPU intrinsics (PR #110179)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,155 @@
+//===-- amdgpuintrin.h - AMDPGU intrinsic functions -----------------------===//
+//
+// 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 __AMDGPUINTRIN_H
+#define __AMDGPUINTRIN_H
+
+#ifndef __AMDGPU__
+#error "This file is intended for AMDGPU targets or offloading to AMDGPU"
+#endif
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#if !defined(_DEFAULT_FN_ATTRS)
+#if defined(__HIP__) || defined(__CUDA__)
+#define _DEFAULT_FN_ATTRS __attribute__((device))
+#else
+#define _DEFAULT_FN_ATTRS
+#endif
+#endif
+
+#pragma omp begin declare target device_type(nohost)
+#pragma omp begin declare variant match(device = {arch(amdgcn)})
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AaronBallman wrote:

How much do we have to worry about users defining any of these as macros prior to including the system header?

https://github.com/llvm/llvm-project/pull/110179