编写一个汇编函数求x!，再编写一个C程序，调用此函数来计算1!+2!+…+6！

汇编函数代码如下：

section .text
global factorial

factorial:
    push ebp
    mov ebp, esp
    mov eax, [ebp+8]
    cmp eax, 1
    jle end
    dec eax
    push eax
    call factorial
    mov ebx, [ebp+8]
    imul ebx, eax
    jmp end
end:
    mov esp, ebp
    pop ebp
    ret

C程序代码如下：

#include <stdio.h>

extern int factorial(int x);

int main() {
    int i;
    for (i = 1; i <= 6; i++) {
        printf("%d! = %d\n", i, factorial(i));
    }
    return ;
}

输出结果如下：

1! = 1
2! = 2
3! = 6
4! = 24
5! = 120
6! = 720