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/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Written by H. Peter Anvin <hpa@zytor.com>
 * Brought in from Linux v4.4 and modified for U-Boot
 * From Linux arch/um/sys-i386/setjmp.S
 */

#define _REGPARM

/*
 * The jmp_buf is assumed to contain the following, in order:
 *	%ebx
 *	%esp
 *	%ebp
 *	%esi
 *	%edi
 *	<return address>
 */

	.text
	.align 4
	.globl setjmp
	.type setjmp, @function
setjmp:
#ifdef _REGPARM
	movl %eax, %edx
#else
	movl 4(%esp), %edx
#endif
	popl %ecx		/* Return address, and adjust the stack */
	xorl %eax, %eax		/* Return value */
	movl %ebx, (%edx)
	movl %esp, 4(%edx)	/* Post-return %esp! */
	pushl %ecx		/* Make the call/return stack happy */
	movl %ebp, 8(%edx)
	movl %esi, 12(%edx)
	movl %edi, 16(%edx)
	movl %ecx, 20(%edx)	/* Return address */
	ret

	/* Provide function size if needed */
	.size setjmp, .-setjmp

	.align 4
	.globl longjmp
	.type longjmp, @function
longjmp:
#ifdef _REGPARM
	xchgl %eax, %edx
#else
	movl 4(%esp), %edx	/* jmp_ptr address */
#endif
	movl (%edx), %ebx
	movl 4(%edx), %esp
	movl 8(%edx), %ebp
	movl 12(%edx), %esi
	movl 16(%edx), %edi
	jmp *20(%edx)

	.size longjmp, .-longjmp