diff options
Diffstat (limited to 'sysdeps/x86/sysdep.h')
-rw-r--r-- | sysdeps/x86/sysdep.h | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/sysdeps/x86/sysdep.h b/sysdeps/x86/sysdep.h new file mode 100644 index 0000000000..8776ad8374 --- /dev/null +++ b/sysdeps/x86/sysdep.h @@ -0,0 +1,104 @@ +/* Assembler macros for x86. + Copyright (C) 2017-2018 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _X86_SYSDEP_H +#define _X86_SYSDEP_H 1 + +#include <sysdeps/generic/sysdep.h> + +/* __CET__ is defined by GCC with Control-Flow Protection values: + +enum cf_protection_level +{ + CF_NONE = 0, + CF_BRANCH = 1 << 0, + CF_RETURN = 1 << 1, + CF_FULL = CF_BRANCH | CF_RETURN, + CF_SET = 1 << 2 +}; +*/ + +/* Set if CF_BRANCH (IBT) is enabled. */ +#define X86_FEATURE_1_IBT (1U << 0) +/* Set if CF_RETURN (SHSTK) is enabled. */ +#define X86_FEATURE_1_SHSTK (1U << 1) + +#ifdef __CET__ +# define CET_ENABLED 1 +# define IBT_ENABLED (__CET__ & X86_FEATURE_1_IBT) +# define SHSTK_ENABLED (__CET__ & X86_FEATURE_1_SHSTK) +#else +# define CET_ENABLED 0 +# define IBT_ENABLED 0 +# define SHSTK_ENABLED 0 +#endif + +#ifdef __ASSEMBLER__ + +/* Syntactic details of assembler. */ + +#ifdef _CET_ENDBR +# define _CET_NOTRACK notrack +#else +# define _CET_ENDBR +# define _CET_NOTRACK +#endif + +/* ELF uses byte-counts for .align, most others use log2 of count of bytes. */ +#define ALIGNARG(log2) 1<<log2 +#define ASM_SIZE_DIRECTIVE(name) .size name,.-name; + +/* Define an entry point visible from C. */ +#define ENTRY(name) \ + .globl C_SYMBOL_NAME(name); \ + .type C_SYMBOL_NAME(name),@function; \ + .align ALIGNARG(4); \ + C_LABEL(name) \ + cfi_startproc; \ + _CET_ENDBR; \ + CALL_MCOUNT + +#undef END +#define END(name) \ + cfi_endproc; \ + ASM_SIZE_DIRECTIVE(name) + +#define ENTRY_CHK(name) ENTRY (name) +#define END_CHK(name) END (name) + +/* Since C identifiers are not normally prefixed with an underscore + on this system, the asm identifier `syscall_error' intrudes on the + C name space. Make sure we use an innocuous name. */ +#define syscall_error __syscall_error +#define mcount _mcount + +#undef PSEUDO_END +#define PSEUDO_END(name) \ + END (name) + +/* Local label name for asm code. */ +#ifndef L +/* ELF-like local names start with `.L'. */ +# define L(name) .L##name +#endif + +#define atom_text_section .section ".text.atom", "ax" + +#endif /* __ASSEMBLER__ */ + +#endif /* _X86_SYSDEP_H */ |