[clang] [RISCV] Implement Clang Builtins for XCVmac Extension in CV32E40P (PR #110623)

[Paolo Savini via cfe-commits]

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@@ -0,0 +1,111 @@
+/*===---- riscv_corev_mac.h - CORE-V multiply accumulate intrinsics --------===
+ *
+ * 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 __RISCV_COREV_MAC_H
+#define __RISCV_COREV_MAC_H
+
+#include <stdint.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+#if defined(__riscv_xcvmac)
+
+#define __DEFAULT_FN_ATTRS __attribute__((__always_inline__, __nodebug__))
+
+static __inline__ long __DEFAULT_FN_ATTRS __riscv_cv_mac_mac(long a, long b,
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PaoloS02 wrote:

That was to follow the RISC-V C API headers specification according to which we should use `long` for types that correspond to the `XLEN` like `int`

https://github.com/llvm/llvm-project/pull/110623