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	I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
		
			
				
	
	
		
			134 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			134 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /* Save current context.
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|    Copyright (C) 2001-2021 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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|    Contributed by Ulrich Drepper <drepper@redhat.com>, 2001.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, see
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|    <https://www.gnu.org/licenses/>.  */
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| 
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| #include <sysdep.h>
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| #include <asm/prctl.h>
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| 
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| #include "ucontext_i.h"
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| 
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| 
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| ENTRY(__getcontext)
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| 	/* Load address of the context data structure.  */
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| 	movl	4(%esp), %eax
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| 
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| 	/* Save the preserved register values and the return address.  */
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| 	movl	%edi, oEDI(%eax)
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| 	movl	%esi, oESI(%eax)
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| 	movl	%ebp, oEBP(%eax)
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| 	movl	(%esp), %ecx
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| 	movl	%ecx, oEIP(%eax)
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| 	leal	4(%esp), %ecx		/* Exclude the return address.  */
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| 	movl	%ecx, oESP(%eax)
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| 	movl	%ebx, oEBX(%eax)
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| 
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| 	/* Save the FS segment register.  We don't touch the GS register
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| 	   since it is used for threads.  */
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| 	xorl	%edx, %edx
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| 	movw	%fs, %dx
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| 	movl	%edx, oFS(%eax)
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| 
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| #if SHSTK_ENABLED
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| 	/* Check if shadow stack is enabled.  */
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| 	testl	$X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
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| 	jz	L(no_shstk)
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| 
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| 	/* Save EAX in EDX.  */
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| 	movl	%eax, %edx
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| 
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| 	xorl	%eax, %eax
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| 	cmpl	%gs:SSP_BASE_OFFSET, %eax
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| 	jnz	L(shadow_stack_bound_recorded)
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| 
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| 	/* Save EBX in the first scratch register slot.  */
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| 	movl	%ebx, oSCRATCH1(%edx)
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| 
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| 	/* Get the base address and size of the default shadow stack
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| 	   which must be the current shadow stack since nothing has
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| 	   been recorded yet.  */
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| 	sub	$24, %esp
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| 	mov	%esp, %ecx
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| 	movl	$ARCH_CET_STATUS, %ebx
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| 	movl	$__NR_arch_prctl, %eax
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| 	ENTER_KERNEL
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| 	testl	%eax, %eax
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| 	jz	L(continue_no_err)
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| 
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| 	/* This should never happen.  */
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| 	hlt
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| 
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| L(continue_no_err):
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| 	/* Restore EBX from the first scratch register slot.  */
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| 	movl	oSCRATCH1(%edx), %ebx
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| 
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| 	/* Record the base of the current shadow stack.  */
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| 	movl	8(%esp), %eax
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| 	movl	%eax, %gs:SSP_BASE_OFFSET
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| 	add	$24, %esp
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| 
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| L(shadow_stack_bound_recorded):
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| 	/* Load address of the context data structure.  */
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| 	movl	4(%esp), %eax
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| 
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| 	/* Get the current shadow stack pointer.  */
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| 	rdsspd	%edx
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| 	/* NB: Save the caller's shadow stack so that we can jump back
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| 	   to the caller directly.  */
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| 	addl	$4, %edx
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| 	movl	%edx, oSSP(%eax)
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| 
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| 	/* Save the current shadow stack base in ucontext.  */
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| 	movl	%gs:SSP_BASE_OFFSET, %edx
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| 	movl	%edx, (oSSP + 4)(%eax)
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| 
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| L(no_shstk):
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| #endif
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| 	/* We have separate floating-point register content memory on the
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| 	   stack.  We use the __fpregs_mem block in the context.  Set the
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| 	   links up correctly.  */
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| 	leal	oFPREGSMEM(%eax), %ecx
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| 	movl	%ecx, oFPREGS(%eax)
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| 	/* Save the floating-point context.  */
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| 	fnstenv	(%ecx)
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| 	/* And load it right back since the processor changes the mask.
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| 	   Intel thought this opcode to be used in interrupt handlers which
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| 	   would block all exceptions.  */
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| 	fldenv	(%ecx)
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| 
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| 	/* Save the current signal mask.  */
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| 	pushl	%ebx
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| 	cfi_adjust_cfa_offset (4)
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| 	cfi_rel_offset (ebx, 0)
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| 	leal	oSIGMASK(%eax), %edx
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| 	xorl	%ecx, %ecx
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| 	movl	$SIG_BLOCK, %ebx
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| 	movl	$__NR_sigprocmask, %eax
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| 	ENTER_KERNEL
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| 	popl	%ebx
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| 	cfi_adjust_cfa_offset (-4)
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| 	cfi_restore (ebx)
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| 	cmpl	$-4095, %eax		/* Check %eax for error.  */
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| 	jae	SYSCALL_ERROR_LABEL	/* Jump to error handler if error.  */
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| 
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| 	/* All done, return 0 for success.  */
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| 	xorl	%eax, %eax
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| 	ret
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| PSEUDO_END(__getcontext)
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| 
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| weak_alias (__getcontext, getcontext)
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