[clang] [compiler-rt] [SafeStack] Introduce public interface header and deprecate builtins (PR #198292)

[Jakob Koschel via cfe-commits]

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@@ -0,0 +1,35 @@
+//===-- sanitizer/safestack_interface.h -------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of SafeStack.
+//
+// Public interface header.
+//===----------------------------------------------------------------------===//
+#ifndef SANITIZER_SAFESTACK_INTERFACE_H
+#define SANITIZER_SAFESTACK_INTERFACE_H
+
+#include <sanitizer/common_interface_defs.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/// Returns the current unsafe stack pointer of the current thread.
+void SANITIZER_CDECL *__safestack_get_unsafe_stack_ptr(void);
+
+/// Returns a pointer to the bottom of the unsafe stack of the current thread.
+void SANITIZER_CDECL *__safestack_get_unsafe_stack_bottom(void);
+
+/// Returns a pointer to the top of the unsafe stack of the current thread.
+void SANITIZER_CDECL *__safestack_get_unsafe_stack_top(void);
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jakos-sec wrote:

Done, also made them `const void *`, thank you for the suggestion!

https://github.com/llvm/llvm-project/pull/198292