[libc-commits] [libc] [libc] add checksum for jmpbuf (PR #101110)

[Paul Kirth via libc-commits]

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@@ -0,0 +1,67 @@
+//===-- Implementation header for jmpbuf checksum ---------------*- 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_SETJMP_CHECKSUM_H
+#define LLVM_LIBC_SRC_SETJMP_CHECKSUM_H
+
+#include "src/__support/hash.h"
+#include "src/__support/macros/attributes.h"
+#include "src/__support/macros/config.h"
+#include "src/setjmp/setjmp_impl.h"
+#include "src/stdlib/abort.h"
+#include "src/unistd/write.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+namespace jmpbuf {
+using HashState = internal::HashState;
+// Initial values generated by
+// https://www.random.org/cgi-bin/randbyte?nbytes=48&format=h
+// These values are only used for overlay targets.
+LIBC_INLINE_VAR uint64_t register_mangle_cookie = 0xdf8a883867040cbc;
+LIBC_INLINE_VAR uint64_t checksum_mangle_cookie = 0x9ed4fe406ebe9cf9;
+LIBC_INLINE_VAR uint64_t randomness[4] = {
+    0x83b9df7dddf5ab3d,
+    0x06c931cca75e15c6,
+    0x08280ec9e9a778bf,
+    0x111f67f4aafc9276,
+};
----------------
ilovepi wrote:

Yeah, that sounds reasonable. For other targets, like baremetal, we may want to think about other means of initialization,  but that's out of scope for this patch.

https://github.com/llvm/llvm-project/pull/101110