[clang] [llvm] [X86][AMX] Support AMX-FP8 (PR #113850)

[Phoebe Wang via cfe-commits]

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@@ -0,0 +1,92 @@
+/*===------------- amxfp8intrin.h - AMX intrinsics -*- C++ -*----------------===
+ *
+ * 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 __IMMINTRIN_H
+#error "Never use <amxfp8intrin.h> directly; include <immintrin.h> instead."
+#endif /* __IMMINTRIN_H */
+
+#ifndef __AMXFP8INTRIN_H
+#define __AMXFP8INTRIN_H
+#ifdef __x86_64__
+
+/// These instructions compute dot product of brain-float8 (BF8) or
+/// hybrid-float8 (HF8) accumulating into a single precision (FP32). The input
+/// elements can be BF8 or HF8. These instructions have three tile operands, one
+/// source/dest accumulator operand, and two source operands, \a a and \a b. The
+/// \a a and \a b operands can be BF8 or HF8 independently, and the source/dest
+/// operand, \a dst is always FP32.
----------------
phoebewang wrote:

We usually don't add description for the whole file. I think we can simply remove it, ot If you want, you can follow the way like https://github.com/llvm/llvm-project/blob/main/clang/lib/Headers/stddef.h#L10-L21

https://github.com/llvm/llvm-project/pull/113850