================ @@ -0,0 +1,115 @@ +//===--- RunOnNewStack.cpp - Crash Recovery -------------------------------===// +// +// 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 +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/ProgramStack.h" +#include "llvm/Config/config.h" +#include "llvm/Support/Compiler.h" + +#ifdef HAVE_SYS_RESOURCE_H +# include <sys/resource.h> +#endif + +#ifdef _MSC_VER +# include <intrin.h> // for _AddressOfReturnAddress +#endif + +// Currently only Apple AArch64 is known to support split stacks in the debugger +// and other tooling. +#if defined(__APPLE__) && defined(__aarch64__) && \ + LLVM_HAS_CPP_ATTRIBUTE(gnu::naked) && __has_extension(gnu_asm) +# define LLVM_HAS_SPLIT_STACKS +# define LLVM_HAS_SPLIT_STACKS_AARCH64 +#include <sys/mman.h> +#endif + +#ifndef LLVM_HAS_SPLIT_STACKS +# include "llvm/Support/thread.h" +#endif + +using namespace llvm; + +uintptr_t llvm::getStackPointer() { +#if __GNUC__ || __has_builtin(__builtin_frame_address) + return (uintptr_t)__builtin_frame_address(0); +#elif defined(_MSC_VER) + return (uintptr_t)_AddressOfReturnAddress(); +#else + char CharOnStack = 0; ---------------- rnk wrote:
This `#else` case breaks down in situations where the compiler moves all the user data out to the heap, like with Seperate Data And Control Stacks (SCADS) or ASan use-after-return detection mode. I think we probably don't care, since those will be handled above. I guess I don't have any actionable suggestions, other than to make the character variable itself volatile. It seems to me like it would be semantics-preserving for a compiler to promote CharOnStack into a global constant 0, for example, since we never write through the pointer that we store into a volatile local. https://github.com/llvm/llvm-project/pull/133173 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
