[clang] clang: Add builtin header for amdhsa abi (PR #181993)

[Joseph Huber via cfe-commits]

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@@ -0,0 +1,80 @@
+//===-- amdhsa_abi.h - AMDHSA ABI definition utilities --------------------===//
+//
+// 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 __AMDHSA_ABI_H
+#define __AMDHSA_ABI_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+typedef struct __attribute__((aligned(8))) amdhsa_implicit_kernarg_v5 {
+  uint32_t block_count[3];
+  uint16_t group_size[3];
+  uint16_t remainder[3];
+  char reserved0[16];
+  uint64_t global_offset[3];
+  uint16_t grid_dims;
+  char reserved1[14];
+  __attribute__((opencl_global)) void *hostcall_buffer;
+  __attribute__((opencl_global)) void *multigrid_sync_arg;
+  __attribute__((opencl_global)) void *heap_v1;
+  __attribute__((opencl_global)) void *default_queue;
+  __attribute__((opencl_global)) void *completion_action;
+  char reserved2[72];
+  uint32_t private_base; // Unused on gfx9+
+  uint32_t shared_base;  // Unused on gfx9+
+  __attribute__((opencl_global)) void *queue_ptr;
+  char reserved3[48];
+} amdhsa_implicit_kernarg_v5;
+
+_Static_assert(sizeof(amdhsa_implicit_kernarg_v5) == 256, "wrong struct size");
+
+_Static_assert(offsetof(amdhsa_implicit_kernarg_v5, block_count[0]) == 0,
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jhuber6 wrote:

Not sure we need to assert on every member of a naturally aligned struct, but I suppose it does prove that the offsets we use are correct.

https://github.com/llvm/llvm-project/pull/181993