diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/x86_64/sysdep.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/x86_64/sysdep.h | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/x86_64/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/sysdep.h index 0dc2f2750e..5dfffca455 100644 --- a/sysdeps/unix/sysv/linux/x86_64/sysdep.h +++ b/sysdeps/unix/sysv/linux/x86_64/sysdep.h @@ -311,4 +311,31 @@ #endif /* __ASSEMBLER__ */ + +/* Pointer mangling support. */ +#if defined NOT_IN_libc && defined IS_IN_rtld +/* We cannot use the thread descriptor because in ld.so we use setjmp + earlier than the descriptor is initialized. */ +# ifdef __ASSEMBLER__ +# define PTR_MANGLE(reg) xorq __pointer_chk_guard_local(%rip), reg +# define PTR_DEMANGLE(reg) PTR_MANGLE (reg) +# else +# define PTR_MANGLE(reg) asm ("xorq __pointer_chk_guard_local(%%rip), %0"\ + : "=r" (reg) : "0" (reg)) +# define PTR_DEMANGLE(reg) PTR_MANGLE (reg) +# endif +#else +# ifdef __ASSEMBLER__ +# define PTR_MANGLE(reg) xorq %fs:POINTER_GUARD, reg +# define PTR_DEMANGLE(reg) PTR_MANGLE (reg) +# else +# define PTR_MANGLE(var) asm ("xorq %%fs:%c2, %0" \ + : "=r" (var) \ + : "0" (var), \ + "i" (offsetof (tcbhead_t, \ + pointer_guard))) +# define PTR_DEMANGLE(var) PTR_MANGLE (var) +# endif +#endif + #endif /* linux/x86_64/sysdep.h */ |