mirror of
				https://sourceware.org/git/glibc.git
				synced 2025-11-03 20:53:13 +03:00 
			
		
		
		
	No bug. This change adds a new macro ENTRY_P2ALIGN which takes a second argument, log2 of the desired function alignment. The old ENTRY(name) macro is just ENTRY_P2ALIGN(name, 4) so this doesn't affect any existing functionality. Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>
		
			
				
	
	
		
			122 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			122 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Assembler macros for x86.
 | 
						|
   Copyright (C) 2017-2021 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
 | 
						|
   <https://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
 | 
						|
 | 
						|
/* Offset for fxsave/xsave area used by _dl_runtime_resolve.  Also need
 | 
						|
   space to preserve RCX, RDX, RSI, RDI, R8, R9 and RAX.  It must be
 | 
						|
   aligned to 16 bytes for fxsave and 64 bytes for xsave.  */
 | 
						|
#define STATE_SAVE_OFFSET (8 * 7 + 8)
 | 
						|
 | 
						|
/* Save SSE, AVX, AVX512, mask and bound registers.  */
 | 
						|
#define STATE_SAVE_MASK \
 | 
						|
  ((1 << 1) | (1 << 2) | (1 << 3) | (1 << 5) | (1 << 6) | (1 << 7))
 | 
						|
 | 
						|
/* Constants for bits in __x86_string_control:  */
 | 
						|
 | 
						|
/* Avoid short distance REP MOVSB.  */
 | 
						|
#define X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB	(1 << 0)
 | 
						|
 | 
						|
#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_P2ALIGN(name, alignment)					      \
 | 
						|
  .globl C_SYMBOL_NAME(name);						      \
 | 
						|
  .type C_SYMBOL_NAME(name),@function;					      \
 | 
						|
  .align ALIGNARG(alignment);						      \
 | 
						|
  C_LABEL(name)								      \
 | 
						|
  cfi_startproc;							      \
 | 
						|
  _CET_ENDBR;								      \
 | 
						|
  CALL_MCOUNT
 | 
						|
 | 
						|
/* Common entry 16 byte aligns.  */
 | 
						|
#define ENTRY(name) ENTRY_P2ALIGN (name, 4)
 | 
						|
 | 
						|
#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 */
 |