Given the following C code and unoptimized assembly code, your task is to generate highly optimized x86-64 assembly code.
C Code:

```c
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main()
{
    char s[1000000];
    scanf("%s", s);
    int len = strlen(s);
    int ans = 0;
    for(int i = 0, j = len - 1; i <= j; i++, j--){
        if(s[i] == s[j]){
            continue;
        }
        while(s[i] == 'x'){
            i++;
            ans++;
        }
        while(s[j] == 'x'){
            j--;
            ans++;
        }
        if(s[i] != s[j]){
            printf("-1");
            return 0;
        }
    }
    printf("%d", ans);
    return 0;
}
```

Unoptimized Assembly Code:

```assembly
	.file	"temp.c"
	.text
	.section	.rodata
.LC0:
	.string	"%s"
.LC1:
	.string	"-1"
.LC2:
	.string	"%d"
	.text
	.globl	main
	.type	main, @function
main:
.LFB6:
	.cfi_startproc
	endbr64
	pushq	%rbp
	.cfi_def_cfa_offset 16
	.cfi_offset 6, -16
	movq	%rsp, %rbp
	.cfi_def_cfa_register 6
	leaq	-999424(%rsp), %r11
.LPSRL0:
	subq	$4096, %rsp
	orq	$0, (%rsp)
	cmpq	%r11, %rsp
	jne	.LPSRL0
	subq	$608, %rsp
	movq	%fs:40, %rax
	movq	%rax, -8(%rbp)
	xorl	%eax, %eax
	leaq	-1000016(%rbp), %rax
	movq	%rax, %rsi
	leaq	.LC0(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	__isoc99_scanf@PLT
	leaq	-1000016(%rbp), %rax
	movq	%rax, %rdi
	call	strlen@PLT
	movl	%eax, -1000020(%rbp)
	movl	$0, -1000032(%rbp)
	movl	$0, -1000028(%rbp)
	movl	-1000020(%rbp), %eax
	subl	$1, %eax
	movl	%eax, -1000024(%rbp)
	jmp	.L2
.L10:
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %edx
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	%al, %dl
	je	.L13
	jmp	.L5
.L6:
	addl	$1, -1000028(%rbp)
	addl	$1, -1000032(%rbp)
.L5:
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	$120, %al
	je	.L6
	jmp	.L7
.L8:
	subl	$1, -1000024(%rbp)
	addl	$1, -1000032(%rbp)
.L7:
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	$120, %al
	je	.L8
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %edx
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	%al, %dl
	je	.L4
	leaq	.LC1(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	printf@PLT
	movl	$0, %eax
	jmp	.L11
.L13:
	nop
.L4:
	addl	$1, -1000028(%rbp)
	subl	$1, -1000024(%rbp)
.L2:
	movl	-1000028(%rbp), %eax
	cmpl	-1000024(%rbp), %eax
	jle	.L10
	movl	-1000032(%rbp), %eax
	movl	%eax, %esi
	leaq	.LC2(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	printf@PLT
	movl	$0, %eax
.L11:
	movq	-8(%rbp), %rdx
	subq	%fs:40, %rdx
	je	.L12
	call	__stack_chk_fail@PLT
.L12:
	leave
	.cfi_def_cfa 7, 8
	ret
	.cfi_endproc
.LFE6:
	.size	main, .-main
	.ident	"GCC: (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0"
	.section	.note.GNU-stack,"",@progbits
	.section	.note.gnu.property,"a"
	.align 8
	.long	1f - 0f
	.long	4f - 1f
	.long	5
0:
	.string	"GNU"
1:
	.align 8
	.long	0xc0000002
	.long	3f - 2f
2:
	.long	0x3
3:
	.align 8
4:
```

Only output the optimized assembly code. Do not include any other text. Do not write any comments in the assembly code. Wrap the assembly code in ```assembly``` tags.
user
	.file	"temp.c"
	.text
	.section	.rodata.str1.1,"aMS",@progbits,1
.LC0:
	.string	"%s"
.LC1:
	.string	"-1"
.LC2:
	.string	"%d"
	.section	.text.startup,"ax",@progbits
	.p2align 4
	.globl	main
	.type	main, @function
main:
.LFB39:
	.cfi_startproc
	endbr64
	pushq	%rbp
	.cfi_def_cfa_offset 16
	.cfi_offset 6, -16
	leaq	-999424(%rsp), %r11
	.cfi_def_cfa 11, 999440
.LPSRL0:
	subq	$4096, %rsp
	orq	$0, (%rsp)
	cmpq	%r11, %rsp
	jne	.LPSRL0
	.cfi_def_cfa_register 7
	subq	$592, %rsp
	.cfi_def_cfa_offset 1000032
	leaq	.LC0(%rip), %rdi
	movq	%fs:40, %rax
	movq	%rax, 1000008(%rsp)
	xorl	%eax, %eax
	movq	%rsp, %rbp
	movq	%rbp, %rsi
	call	__isoc99_scanf@PLT
	movq	%rbp, %rdi
	call	strlen@PLT
	testl	%eax, %eax
	je	.L13
	leal	-1(%rax), %r8d
	xorl	%edi, %edi
	leaq	1(%rsp), %r11
	xorl	%edx, %edx
	leaq	-1(%rsp), %r10
	.p2align 4,,10
	.p2align 3
.L9:
	movslq	%edi, %rax
	movzbl	(%rsp,%rax), %ecx
	movslq	%r8d, %rax
	movzbl	(%rsp,%rax), %esi
	cmpb	%sil, %cl
	je	.L3
	cmpb	$120, %cl
	jne	.L4
	leal	1(%rdi), %eax
	subl	%edi, %edx
	cltq
	.p2align 4,,10
	.p2align 3
.L5:
	movl	%eax, %edi
	leal	(%rdx,%rax), %r9d
	addq	$1, %rax
	movzbl	(%r10,%rax), %ecx
	cmpb	$120, %cl
	je	.L5
	cmpb	$120, %sil
	jne	.L25
.L10:
	leal	-1(%r8), %eax
	addl	%r8d, %r9d
	cltq
	.p2align 4,,10
	.p2align 3
.L7:
	movl	%r9d, %edx
	movl	%eax, %r8d
	subl	%eax, %edx
	subq	$1, %rax
	movzbl	(%r11,%rax), %esi
	cmpb	$120, %sil
	je	.L7
.L6:
	cmpb	%sil, %cl
	jne	.L11
.L3:
	addl	$1, %edi
	subl	$1, %r8d
	cmpl	%r8d, %edi
	jle	.L9
.L2:
	leaq	.LC2(%rip), %rsi
	movl	$1, %edi
	xorl	%eax, %eax
	call	__printf_chk@PLT
.L8:
	movq	1000008(%rsp), %rax
	subq	%fs:40, %rax
	jne	.L26
	addq	$1000016, %rsp
	.cfi_remember_state
	.cfi_def_cfa_offset 16
	xorl	%eax, %eax
	popq	%rbp
	.cfi_def_cfa_offset 8
	ret
	.p2align 4,,10
	.p2align 3
.L4:
	.cfi_restore_state
	cmpb	$120, %sil
	jne	.L11
	movl	%edx, %r9d
	jmp	.L10
.L25:
	movl	%r9d, %edx
	jmp	.L6
.L11:
	leaq	.LC1(%rip), %rsi
	movl	$1, %edi
	xorl	%eax, %eax
	call	__printf_chk@PLT
	jmp	.L8
.L13:
	xorl	%edx, %edx
	jmp	.L2
.L26:
	call	__stack_chk_fail@PLT
	.cfi_endproc
.LFE39:
	.size	main, .-main
	.ident	"GCC: (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0"
	.section	.note.GNU-stack,"",@progbits
	.section	.note.gnu.property,"a"
	.align 8
	.long	1f - 0f
	.long	4f - 1f
	.long	5
0:
	.string	"GNU"
1:
	.align 8
	.long	0xc0000002
	.long	3f - 2f
2:
	.long	0x3
3:
	.align 8
4:

rule
	.file	"temp.c"
	.text
	.section	.rodata.str1.1,"aMS",@progbits,1
.LC0:
	.string	"%s"
.LC1:
	.string	"-1"
.LC2:
	.string	"%d"
	.section	.text.startup,"ax",@progbits
	.p2align 4
	.globl	main
	.type	main, @function
main:
.LFB39:
	.cfi_startproc
	endbr64
	pushq	%rbp
	.cfi_def_cfa_offset 16
	.cfi_offset 6, -16
	leaq	-999424(%rsp), %r11
	.cfi_def_cfa 11, 999440
.LPSRL0:
	subq	$4096, %rsp
	orq	$0, (%rsp)
	cmpq	%r11, %rsp
	jne	.LPSRL0
	.cfi_def_cfa_register 7
	subq	$592, %rsp
	.cfi_def_cfa_offset 1000032
	leaq	.LC0(%rip), %rdi
	movq	%fs:40, %rax
	movq	%rax, 1000008(%rsp)
	xorl	%eax, %eax
	movq	%rsp, %rbp
	movq	%rbp, %rsi
	call	__isoc99_scanf@PLT
	movq	%rbp, %rdi
	call	strlen@PLT
	testl	%eax, %eax
	je	.L13
	leal	-1(%rax), %r8d
	xorl	%edi, %edi
	leaq	1(%rsp), %r11
	xorl	%edx, %edx
	leaq	-1(%rsp), %r10
	.p2align 4,,10
	.p2align 3
.L9:
	movslq	%edi, %rax
	movzbl	(%rsp,%rax), %ecx
	movslq	%r8d, %rax
	movzbl	(%rsp,%rax), %esi
	cmpb	%sil, %cl
	je	.L3
	cmpb	$120, %cl
	jne	.L4
	leal	1(%rdi), %eax
	subl	%edi, %edx
	cltq
	.p2align 4,,10
	.p2align 3
.L5:
	movl	%eax, %edi
	leal	(%rdx,%rax), %r9d
	addq	$1, %rax
	movzbl	(%r10,%rax), %ecx
	cmpb	$120, %cl
	je	.L5
	cmpb	$120, %sil
	jne	.L25
.L10:
	leal	-1(%r8), %eax
	addl	%r8d, %r9d
	cltq
	.p2align 4,,10
	.p2align 3
.L7:
	movl	%r9d, %edx
	movl	%eax, %r8d
	subl	%eax, %edx
	subq	$1, %rax
	movzbl	(%r11,%rax), %esi
	cmpb	$120, %sil
	je	.L7
.L6:
	cmpb	%sil, %cl
	jne	.L11
.L3:
	addl	$1, %edi
	subl	$1, %r8d
	cmpl	%r8d, %edi
	jle	.L9
.L2:
	leaq	.LC2(%rip), %rsi
	movl	$1, %edi
	xorl	%eax, %eax
	call	__printf_chk@PLT
.L8:
	movq	1000008(%rsp), %rax
	subq	%fs:40, %rax
	jne	.L26
	addq	$1000016, %rsp
	.cfi_remember_state
	.cfi_def_cfa_offset 16
	xorl	%eax, %eax
	popq	%rbp
	.cfi_def_cfa_offset 8
	ret
	.p2align 4,,10
	.p2align 3
.L4:
	.cfi_restore_state
	cmpb	$120, %sil
	jne	.L11
	movl	%edx, %r9d
	jmp	.L10
.L25:
	movl	%r9d, %edx
	jmp	.L6
.L11:
	leaq	.LC1(%rip), %rsi
	movl	$1, %edi
	xorl	%eax, %eax
	call	__printf_chk@PLT
	jmp	.L8
.L13:
	xorl	%edx, %edx
	jmp	.L2
.L26:
	call	__stack_chk_fail@PLT
	.cfi_endproc
.LFE39:
	.size	main, .-main
	.ident	"GCC: (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0"
	.section	.note.GNU-stack,"",@progbits
	.section	.note.gnu.property,"a"
	.align 8
	.long	1f - 0f
	.long	4f - 1f
	.long	5
0:
	.string	"GNU"
1:
	.align 8
	.long	0xc0000002
	.long	3f - 2f
2:
	.long	0x3
3:
	.align 8
4:

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main()
{
    char s[1000000];
    scanf("%s", s);
    int len = strlen(s);
    int ans = 0;
    for(int i = 0, j = len - 1; i <= j; i++, j--){
        if(s[i] == s[j]){
            continue;
        }
        while(s[i] == 'x'){
            i++;
            ans++;
        }
        while(s[j] == 'x'){
            j--;
            ans++;
        }
        if(s[i] != s[j]){
            printf("-1");
            return 0;
        }
    }
    printf("%d", ans);
    return 0;
}

b
 axbax
 `b
 xxxo
 tpxt
 c
 bxbax
 b`
 yxxo
 d

0 2 -1 3 1 0 -1 -1 -1 0
Given the following C code and unoptimized assembly code, your task is to generate highly optimized x86-64 assembly code.
C Code:

```c
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main()
{
    char s[1000000];
    scanf("%s", s);
    int len = strlen(s);
    int ans = 0;
    for(int i = 0, j = len - 1; i <= j; i++, j--){
        if(s[i] == s[j]){
            continue;
        }
        while(s[i] == 'x'){
            i++;
            ans++;
        }
        while(s[j] == 'x'){
            j--;
            ans++;
        }
        if(s[i] != s[j]){
            printf("-1");
            return 0;
        }
    }
    printf("%d", ans);
    return 0;
}
```

Unoptimized Assembly Code:

```assembly
	.file	"temp.c"
	.text
	.section	.rodata
.LC0:
	.string	"%s"
.LC1:
	.string	"-1"
.LC2:
	.string	"%d"
	.text
	.globl	main
	.type	main, @function
main:
.LFB6:
	.cfi_startproc
	endbr64
	pushq	%rbp
	.cfi_def_cfa_offset 16
	.cfi_offset 6, -16
	movq	%rsp, %rbp
	.cfi_def_cfa_register 6
	leaq	-999424(%rsp), %r11
.LPSRL0:
	subq	$4096, %rsp
	orq	$0, (%rsp)
	cmpq	%r11, %rsp
	jne	.LPSRL0
	subq	$608, %rsp
	movq	%fs:40, %rax
	movq	%rax, -8(%rbp)
	xorl	%eax, %eax
	leaq	-1000016(%rbp), %rax
	movq	%rax, %rsi
	leaq	.LC0(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	__isoc99_scanf@PLT
	leaq	-1000016(%rbp), %rax
	movq	%rax, %rdi
	call	strlen@PLT
	movl	%eax, -1000020(%rbp)
	movl	$0, -1000032(%rbp)
	movl	$0, -1000028(%rbp)
	movl	-1000020(%rbp), %eax
	subl	$1, %eax
	movl	%eax, -1000024(%rbp)
	jmp	.L2
.L10:
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %edx
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	%al, %dl
	je	.L13
	jmp	.L5
.L6:
	addl	$1, -1000028(%rbp)
	addl	$1, -1000032(%rbp)
.L5:
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	$120, %al
	je	.L6
	jmp	.L7
.L8:
	subl	$1, -1000024(%rbp)
	addl	$1, -1000032(%rbp)
.L7:
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	$120, %al
	je	.L8
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %edx
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	%al, %dl
	je	.L4
	leaq	.LC1(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	printf@PLT
	movl	$0, %eax
	jmp	.L11
.L13:
	nop
.L4:
	addl	$1, -1000028(%rbp)
	subl	$1, -1000024(%rbp)
.L2:
	movl	-1000028(%rbp), %eax
	cmpl	-1000024(%rbp), %eax
	jle	.L10
	movl	-1000032(%rbp), %eax
	movl	%eax, %esi
	leaq	.LC2(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	printf@PLT
	movl	$0, %eax
.L11:
	movq	-8(%rbp), %rdx
	subq	%fs:40, %rdx
	je	.L12
	call	__stack_chk_fail@PLT
.L12:
	leave
	.cfi_def_cfa 7, 8
	ret
	.cfi_endproc
.LFE6:
	.size	main, .-main
	.ident	"GCC: (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0"
	.section	.note.GNU-stack,"",@progbits
	.section	.note.gnu.property,"a"
	.align 8
	.long	1f - 0f
	.long	4f - 1f
	.long	5
0:
	.string	"GNU"
1:
	.align 8
	.long	0xc0000002
	.long	3f - 2f
2:
	.long	0x3
3:
	.align 8
4:
```

Only output the optimized assembly code. Do not include any other text. Do not write any comments in the assembly code. Wrap the assembly code in ```assembly``` tags.
train
	.file	"temp.c"
	.text
	.section	.rodata
.LC0:
	.string	"%s"
.LC1:
	.string	"-1"
.LC2:
	.string	"%d"
	.text
	.globl	main
	.type	main, @function
main:
.LFB6:
	.cfi_startproc
	endbr64
	pushq	%rbp
	.cfi_def_cfa_offset 16
	.cfi_offset 6, -16
	movq	%rsp, %rbp
	.cfi_def_cfa_register 6
	leaq	-999424(%rsp), %r11
.LPSRL0:
	subq	$4096, %rsp
	orq	$0, (%rsp)
	cmpq	%r11, %rsp
	jne	.LPSRL0
	subq	$608, %rsp
	movq	%fs:40, %rax
	movq	%rax, -8(%rbp)
	xorl	%eax, %eax
	leaq	-1000016(%rbp), %rax
	movq	%rax, %rsi
	leaq	.LC0(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	__isoc99_scanf@PLT
	leaq	-1000016(%rbp), %rax
	movq	%rax, %rdi
	call	strlen@PLT
	movl	%eax, -1000020(%rbp)
	movl	$0, -1000032(%rbp)
	movl	$0, -1000028(%rbp)
	movl	-1000020(%rbp), %eax
	subl	$1, %eax
	movl	%eax, -1000024(%rbp)
	jmp	.L2
.L10:
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %edx
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	%al, %dl
	je	.L13
	jmp	.L5
.L6:
	addl	$1, -1000028(%rbp)
	addl	$1, -1000032(%rbp)
.L5:
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	$120, %al
	je	.L6
	jmp	.L7
.L8:
	subl	$1, -1000024(%rbp)
	addl	$1, -1000032(%rbp)
.L7:
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	$120, %al
	je	.L8
	movl	-1000028(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %edx
	movl	-1000024(%rbp), %eax
	cltq
	movzbl	-1000016(%rbp,%rax), %eax
	cmpb	%al, %dl
	je	.L4
	leaq	.LC1(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	printf@PLT
	movl	$0, %eax
	jmp	.L11
.L13:
	nop
.L4:
	addl	$1, -1000028(%rbp)
	subl	$1, -1000024(%rbp)
.L2:
	movl	-1000028(%rbp), %eax
	cmpl	-1000024(%rbp), %eax
	jle	.L10
	movl	-1000032(%rbp), %eax
	movl	%eax, %esi
	leaq	.LC2(%rip), %rax
	movq	%rax, %rdi
	movl	$0, %eax
	call	printf@PLT
	movl	$0, %eax
.L11:
	movq	-8(%rbp), %rdx
	subq	%fs:40, %rdx
	je	.L12
	call	__stack_chk_fail@PLT
.L12:
	leave
	.cfi_def_cfa 7, 8
	ret
	.cfi_endproc
.LFE6:
	.size	main, .-main
	.ident	"GCC: (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0"
	.section	.note.GNU-stack,"",@progbits
	.section	.note.gnu.property,"a"
	.align 8
	.long	1f - 0f
	.long	4f - 1f
	.long	5
0:
	.string	"GNU"
1:
	.align 8
	.long	0xc0000002
	.long	3f - 2f
2:
	.long	0x3
3:
	.align 8
4:
