[libc-commits] [libc] [libc][c23] add memset_explicit (PR #83577)

[Nick Desaulniers via libc-commits]

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@@ -0,0 +1,29 @@
+//===-- Flush Cacheline for AArch64 -----------------------------*- 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 LLVM_LIBC_SRC_STRING_MEMORY_UTILS_AARCH64_FLUSH_CACHELINE_H
+#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_AARCH64_FLUSH_CACHELINE_H
+
+#include "src/__support/common.h"
+#include <stddef.h> // size_t
+namespace LIBC_NAMESPACE {
+
+LIBC_INLINE size_t cacheline_size() {
+  // Use the same way as in compiler-rt
+  size_t ctr_el0;
+  asm volatile("mrs %0, ctr_el0" : "=r"(ctr_el0));
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nickdesaulniers wrote:

Omit `volatile`; if we call this function but don't use the value, we should skip this inline asm. (or make the return value [[nodiscard]])

https://github.com/llvm/llvm-project/pull/83577