| /* SPDX-License-Identifier: GPL-2.0 */ | |
| #ifndef _LINUX_INSTRUCTION_POINTER_H | |
| #define _LINUX_INSTRUCTION_POINTER_H | |
| #include <asm/linkage.h> | |
| #define _RET_IP_ (unsigned long)__builtin_return_address(0) | |
| #ifndef _THIS_IP_ | |
| #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) | |
| /* | |
| * The current generic definition of _THIS_IP_ is considered broken by GCC [1] | |
| * and Clang [2]. In particular, the address of a label is only expected to be | |
| * used with a computed goto. | |
| * | |
| * [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120071 | |
| * [2] https://github.com/llvm/llvm-project/issues/138272 | |
| * | |
| * Mark it as broken, so that appropriate fallback options can be implemented | |
| * for architectures that do not define their own _THIS_IP_. | |
| */ | |
| #define HAS_BROKEN_THIS_IP | |
| #endif | |
| /* | |
| * _CODE_LOCATION_ provides a unique identifier for the current code location. | |
| * When _THIS_IP_ is broken (generic version), we fall back to a static marker | |
| * which guarantees uniqueness and resolves to a constant address at link time, | |
| * avoiding runtime overhead and compiler optimizations breaking it. | |
| */ | |
| #ifdef HAS_BROKEN_THIS_IP | |
| #define _CODE_LOCATION_ ({ static const char __here; (unsigned long)&__here; }) | |
| #else | |
| #define _CODE_LOCATION_ _THIS_IP_ | |
| #endif | |
| #endif /* _LINUX_INSTRUCTION_POINTER_H */ |