1 /* Assembler macros for x86.
2 Copyright (C) 2017-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
20 #define _X86_SYSDEP_H 1
22 #include <sysdeps/generic/sysdep.h>
24 /* __CET__ is defined by GCC with Control-Flow Protection values:
26 enum cf_protection_level
31 CF_FULL = CF_BRANCH | CF_RETURN,
36 /* Set if CF_BRANCH (IBT) is enabled. */
37 #define X86_FEATURE_1_IBT (1U << 0)
38 /* Set if CF_RETURN (SHSTK) is enabled. */
39 #define X86_FEATURE_1_SHSTK (1U << 1)
42 # define CET_ENABLED 1
43 # define IBT_ENABLED (__CET__ & X86_FEATURE_1_IBT)
44 # define SHSTK_ENABLED (__CET__ & X86_FEATURE_1_SHSTK)
46 # define CET_ENABLED 0
47 # define IBT_ENABLED 0
48 # define SHSTK_ENABLED 0
51 /* Offset for fxsave/xsave area used by _dl_runtime_resolve. Also need
52 space to preserve RCX, RDX, RSI, RDI, R8, R9 and RAX. It must be
53 aligned to 16 bytes for fxsave and 64 bytes for xsave. */
54 #define STATE_SAVE_OFFSET (8 * 7 + 8)
56 /* Save SSE, AVX, AVX512, mask and bound registers. */
57 #define STATE_SAVE_MASK \
58 ((1 << 1) | (1 << 2) | (1 << 3) | (1 << 5) | (1 << 6) | (1 << 7))
60 /* Constants for bits in __x86_string_control: */
62 /* Avoid short distance REP MOVSB. */
63 #define X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB (1 << 0)
67 /* Syntactic details of assembler. */
70 # define _CET_NOTRACK notrack
76 /* ELF uses byte-counts for .align, most others use log2 of count of bytes. */
77 #define ALIGNARG(log2) 1<<log2
78 #define ASM_SIZE_DIRECTIVE(name) .size name,.-name;
80 /* Define an entry point visible from C. */
81 #define ENTRY_P2ALIGN(name, alignment) \
82 .globl C_SYMBOL_NAME(name); \
83 .type C_SYMBOL_NAME(name),@function; \
84 .align ALIGNARG(alignment); \
90 /* Common entry 16 byte aligns. */
91 #define ENTRY(name) ENTRY_P2ALIGN (name, 4)
96 ASM_SIZE_DIRECTIVE(name)
98 #define ENTRY_CHK(name) ENTRY (name)
99 #define END_CHK(name) END (name)
101 /* Since C identifiers are not normally prefixed with an underscore
102 on this system, the asm identifier `syscall_error' intrudes on the
103 C name space. Make sure we use an innocuous name. */
104 #define syscall_error __syscall_error
105 #define mcount _mcount
108 #define PSEUDO_END(name) \
111 /* Local label name for asm code. */
113 /* ELF-like local names start with `.L'. */
114 # define LOCAL_LABEL(name) .L##name
115 # define L(name) LOCAL_LABEL(name)
118 #define atom_text_section .section ".text.atom", "ax"
120 #endif /* __ASSEMBLER__ */
122 #endif /* _X86_SYSDEP_H */