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/* strlen_user.S: Sparc64 optimized strlen_user code
 *
 * Return length of string in userspace including terminating 0
 * or 0 for error
 *
 * Copyright (C) 1991,1996 Free Software Foundation
 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
 * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
 */

#include <asm/asi.h>

#define LO_MAGIC 0x01010101
#define HI_MAGIC 0x80808080

	.align 4
	.global __strlen_user
__strlen_user:
	mov	%o0, %o1
	andcc	%o0, 3, %g0
	be,pt	%icc, 9f
	 sethi	%hi(HI_MAGIC), %o4
10:
	lduba	[%o0] ASI_S, %o5
	brz,pn	%o5, 21f
	 add	%o0, 1, %o0
	andcc	%o0, 3, %g0
	be,pn	%icc, 4f
	 or	%o4, %lo(HI_MAGIC), %o3
11:
	lduba	[%o0] ASI_S, %o5
	brz,pn	%o5, 22f
	 add	%o0, 1, %o0
	andcc	%o0, 3, %g0
	be,pt	%icc, 5f
	 sethi	%hi(LO_MAGIC), %o4
12:
	lduba	[%o0] ASI_S, %o5
	brz,pn	%o5, 23f
	 add	%o0, 1, %o0
	ba,pt	%icc, 13f
	 or	%o4, %lo(LO_MAGIC), %o2
9:
	or	%o4, %lo(HI_MAGIC), %o3
4:
	sethi	%hi(LO_MAGIC), %o4
5:
	or	%o4, %lo(LO_MAGIC), %o2
13:
	lda	[%o0] ASI_S, %o5
2:
	sub	%o5, %o2, %o4
	andcc	%o4, %o3, %g0
	be,pt	%icc, 13b
	 add	%o0, 4, %o0

	/* Check every byte. */
	srl	%o5, 24, %g5
	andcc	%g5, 0xff, %g0
	be,pn	%icc, 1f
	 add	%o0, -3, %o4
	srl	%o5, 16, %g5
	andcc	%g5, 0xff, %g0
	be,pn	%icc, 1f
	 add	%o4, 1, %o4
	srl	%o5, 8, %g5
	andcc	%g5, 0xff, %g0
	be,pn	%icc, 1f
	 add	%o4, 1, %o4
	andcc	%o5, 0xff, %g0
	bne,a,pt %icc, 2b
14:
	 lda	[%o0] ASI_S, %o5
	add	%o4, 1, %o4
1:
	retl
	 sub	%o4, %o1, %o0
21:
	retl
	 mov	1, %o0
22:
	retl
	 mov	2, %o0
23:
	retl
	 mov	3, %o0

        .section .fixup,#alloc,#execinstr
        .align  4
30:
        retl
         clr    %o0

	.section __ex_table,#alloc
	.align	8

	.xword	10b, 30b
	.xword	11b, 30b
	.xword	12b, 30b
	.xword	13b, 30b
	.xword	14b, 30b