/* strcmp with unaligned loads

   Copyright (C) 2013-2018 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

   <http://www.gnu.org/licenses/>.  */

#if IS_IN (libc)

#include "sysdep.h"

ENTRY ( __strcmp_sse2_unaligned)

	movl	%edi, %eax

	xorl	%edx, %edx

	pxor	%xmm7, %xmm7

	orl	%esi, %eax

	andl	$4095, %eax

	cmpl	$4032, %eax

	jg	L(cross_page)

	movdqu	(%rdi), %xmm1

	movdqu	(%rsi), %xmm0

	pcmpeqb	%xmm1, %xmm0

	pminub	%xmm1, %xmm0

	pxor	%xmm1, %xmm1

	pcmpeqb	%xmm1, %xmm0

	pmovmskb	%xmm0, %eax

	testq	%rax, %rax

	je	L(next_48_bytes)

L(return):

	bsfq	%rax, %rdx

	movzbl	(%rdi, %rdx), %eax

	movzbl	(%rsi, %rdx), %edx

	subl	%edx, %eax

	ret

	.p2align 4

L(next_48_bytes):

	movdqu	16(%rdi), %xmm6

	movdqu	16(%rsi), %xmm3

	movdqu	32(%rdi), %xmm5

	pcmpeqb	%xmm6, %xmm3

	movdqu	32(%rsi), %xmm2

	pminub	%xmm6, %xmm3

	pcmpeqb	%xmm1, %xmm3

	movdqu	48(%rdi), %xmm4

	pcmpeqb	%xmm5, %xmm2

	pmovmskb	%xmm3, %edx

	movdqu	48(%rsi), %xmm0

	pminub	%xmm5, %xmm2

	pcmpeqb	%xmm1, %xmm2

	pcmpeqb	%xmm4, %xmm0

	pmovmskb	%xmm2, %eax

	salq	$16, %rdx

	pminub	%xmm4, %xmm0

	pcmpeqb	%xmm1, %xmm0

	salq	$32, %rax

	orq	%rdx, %rax

	pmovmskb	%xmm0, %ecx

	movq	%rcx, %rdx

	salq	$48, %rdx

	orq	%rdx, %rax

	jne	L(return)

L(main_loop_header):

	leaq	64(%rdi), %rdx

	movl	$4096, %ecx

	pxor	%xmm9, %xmm9

	andq	$-64, %rdx

	subq	%rdi, %rdx

	leaq	(%rdi, %rdx), %rax

	addq	%rsi, %rdx

	movq	%rdx, %rsi

	andl	$4095, %esi

	subq	%rsi, %rcx

	shrq	$6, %rcx

	movq	%rcx, %rsi

	jmp	L(loop_start)

	.p2align 4

L(loop):

	addq	$64, %rax

	addq	$64, %rdx

L(loop_start):

	testq	%rsi, %rsi

	leaq	-1(%rsi), %rsi

	je	L(loop_cross_page)

L(back_to_loop):

	movdqu	(%rdx), %xmm0

	movdqu	16(%rdx), %xmm1

	movdqa	(%rax), %xmm2

	movdqa	16(%rax), %xmm3

	pcmpeqb	%xmm2, %xmm0

	movdqu	32(%rdx), %xmm5

	pcmpeqb	%xmm3, %xmm1

	pminub	%xmm2, %xmm0

	movdqu	48(%rdx), %xmm6

	pminub	%xmm3, %xmm1

	movdqa	32(%rax), %xmm2

	pminub	%xmm1, %xmm0

	movdqa	48(%rax), %xmm3

	pcmpeqb	%xmm2, %xmm5

	pcmpeqb	%xmm3, %xmm6

	pminub	%xmm2, %xmm5

	pminub	%xmm3, %xmm6

	pminub	%xmm5, %xmm0

	pminub	%xmm6, %xmm0

	pcmpeqb	%xmm7, %xmm0

	pmovmskb	%xmm0, %ecx

	testl	%ecx, %ecx

	je	L(loop)

	pcmpeqb	%xmm7, %xmm5

	movdqu	(%rdx), %xmm0

	pcmpeqb	%xmm7, %xmm1

	movdqa	(%rax), %xmm2

	pcmpeqb	%xmm2, %xmm0

	pminub	%xmm2, %xmm0

	pcmpeqb	%xmm7, %xmm6

	pcmpeqb	%xmm7, %xmm0

	pmovmskb	%xmm1, %ecx

	pmovmskb	%xmm5, %r8d

	pmovmskb	%xmm0, %edi

	salq	$16, %rcx

	salq	$32, %r8

	pmovmskb	%xmm6, %esi

	orq	%r8, %rcx

	orq	%rdi, %rcx

	salq	$48, %rsi

	orq	%rsi, %rcx

	bsfq	%rcx, %rcx

	movzbl	(%rax, %rcx), %eax

	movzbl	(%rdx, %rcx), %edx

	subl	%edx, %eax

	ret

	.p2align 4

L(loop_cross_page):

	xor	%r10, %r10

	movq	%rdx, %r9

	and	$63, %r9

	subq	%r9, %r10

	movdqa	(%rdx, %r10), %xmm0

	movdqa	16(%rdx, %r10), %xmm1

	movdqu	(%rax, %r10), %xmm2

	movdqu	16(%rax, %r10), %xmm3

	pcmpeqb	%xmm2, %xmm0

	movdqa	32(%rdx, %r10), %xmm5

	pcmpeqb	%xmm3, %xmm1

	pminub	%xmm2, %xmm0

	movdqa	48(%rdx, %r10), %xmm6

	pminub	%xmm3, %xmm1

	movdqu	32(%rax, %r10), %xmm2

	movdqu	48(%rax, %r10), %xmm3

	pcmpeqb	%xmm2, %xmm5

	pcmpeqb	%xmm3, %xmm6

	pminub	%xmm2, %xmm5

	pminub	%xmm3, %xmm6

	pcmpeqb	%xmm7, %xmm0

	pcmpeqb	%xmm7, %xmm1

	pcmpeqb	%xmm7, %xmm5

	pcmpeqb	%xmm7, %xmm6

	pmovmskb	%xmm1, %ecx

	pmovmskb	%xmm5, %r8d

	pmovmskb	%xmm0, %edi

	salq	$16, %rcx

	salq	$32, %r8

	pmovmskb	%xmm6, %esi

	orq	%r8, %rdi

	orq	%rcx, %rdi

	salq	$48, %rsi

	orq	%rsi, %rdi

	movq	%r9, %rcx

	movq	$63, %rsi

	shrq	%cl, %rdi

	test	%rdi, %rdi

	je	L(back_to_loop)

	bsfq	%rdi, %rcx

	movzbl	(%rax, %rcx), %eax

	movzbl	(%rdx, %rcx), %edx

	subl	%edx, %eax

	ret

	.p2align 4

L(cross_page_loop):

	cmpb	%cl, %al

	jne	L(different)

	addq	$1, %rdx

	cmpq	$64, %rdx

	je	L(main_loop_header)

L(cross_page):

	movzbl	(%rdi, %rdx), %eax

	movzbl	(%rsi, %rdx), %ecx

	testb	%al, %al

	jne	L(cross_page_loop)

	xorl	%eax, %eax

L(different):

	subl	%ecx, %eax

	ret

END (__strcmp_sse2_unaligned)

#endif