Question

我需要创建一个程序，按顺序对整数数组进行排序。 C中的问题很简单，代码就是给我们的。

void bubble(int *data, int count)
{
int i, last;
for(last = count‐1; last>0;last‐‐)
{
for(i=0;i<last;i++)
if
(data[i+1] < data[i])
{
/* Swap adjacent elements */
int t=data[i+1];
data[i+1]=data[i];
data[i]=t;
}
}
}

但是当我尝试将它实现到汇编中时，我得到了

Error on line 90: Invalid line
Line 90, Byte 0x00d0: .comm *data,20,4      //data = memory location

或者，如果我评论那条线（我不认为我应该）我得到了这个

Error on line 39: Expecting ')'
Line 39, Byte 0x005a:   mrmovl (%edx,%ebx,4),%eax   //%eax = data[i]
Error on line 41: Expecting ')'
Line 41, Byte 0x0066:   mrmovl 4(%edx,%ebx,4),%edi  //%edi = data[i++]
Error on line 46: Expecting ')'
Line 46, Byte 0x0073:   mrmovl 4(%edx,%ebx,4),%edi  //%edi = data[i++]
Error on line 47: Expecting ')'
Line 47, Byte 0x0079:   rmmovl %edi, (%edx,%ebx,4)  //data[i] = data[i++]
Error on line 48: Expecting ')'
Line 48, Byte 0x007f:   rmmovl %eax, 4(%edx,%ebx,4) //data[i++] = data[i]

以下是我的代码：

    .pos 0

init:   irmovl Stack, %esp  //Set up stack pointer
    irmovl Stack, %ebp  //Set up base pointer
    call main       //call main program
    halt            //Terminate program

bubble: pushl %ebp      //setup
    rrmovl %esp, %ebp

    pushl %edx      //declaring *data
    mrmovl 8(%ebp), %edx        
    pushl %ecx      //declaring count
    mrmovl 12(%ebp), %ecx   
    pushl %ebx      //declaring i
    pushl %esi      //declaring last
    pushl %edi
    pushl %eax
    irmovl $1, %edi     //%edi = 1

    rrmovl %ecx,%esi    //last=count
    subl %edi,%esi      //last--

L1: 
    irmovl $0, %edi     //%edi = 0
    subl %edi,%esi      //last -= 0
    jle L9          //ends loop if last <= 0

    irmovl $0, %ebx     //i = 0
L2:
    rrmovl %ebx, %edi   //%edi = copy of i
    subl %esi,%edi      //%edi = i-last
    jge L8          //ends loop if i >= last

    mrmovl (%edx,%ebx,4),%eax   //%eax = data[i]
    irmovl $1, %edi         //%edi = 1
    mrmovl 4(%edx,%ebx,4),%edi  //%edi = data[i++]

    subl %eax,%edi      //%edi = data[i++]-data[i]
    jge L7          //cancel if statement if data[i++]>=data[i]

    mrmovl 4(%edx,%ebx,4),%edi  //%edi = data[i++]
    rmmovl %edi, (%edx,%ebx,4)  //data[i] = data[i++]
    rmmovl %eax, 4(%edx,%ebx,4) //data[i++] = data[i]

L7:
    irmovl $1, %edi     //%edi = 1
    addl %edi,%ebx      //i++
    jmp L2          //go to beginning of loop
L8:
    irmovl $1, %edi     //%edi = 1
    subl %edi,%esi      //last--
    jmp L1
L9:
    popl %ebx       //finish
    popl %esi
    popl %edi
    popl %eax
    popl %ebp

    ret




main:   pushl %ebp      //setup
    rrmovl %esp, %ebp

    pushl %ebx      //declaring *data
    mrmovl data, %ebx   
    pushl %esi      //declaring count
    mrmovl count, %esi  

    rmmovl %ebx, (%esp) //move data to be used by bubble
    rmmovl %esi, 4(%esp)    //move count to be used by bubble

    call bubble

    popl %ebx       //finish
    popl %esi
    popl %ebp

    ret


.comm data,20,4     //data = memory location
.align 4
count:  .long 5     //count = memory location 
data:   .long 2     //data array assignment
    .long 1
    .long 3
    .long 5
    .long 4

.pos 0x200
Stack: .long 0

Answer 1

y86 不支持带有索引和比例的完整 x86 有效地址语法，它只允许displacement(base)。您必须自己执行地址计算。

y86 汇编程序也不支持.comm，只需使用.long

定义您的数据

无法在Y86 Assembly中创建数组循环

1 个答案: