20155216 2017-2018-1 第八周课下作业1
作业内容：
1、完成家庭作业4.47，4.48，4.49。
2、相应代码反汇编成X86-64汇编。
3、把上述X68-64汇编翻译成Y86-64汇编，并给出相应机器码。
作业4.47
A 编写一个排序代码
#include<stdio.h>
void bubble_a(int *data, int count){
int i,next;
for(next = 1; next < count; next++){
for(i = next - 1; i >= 0; i--)
if(*(data + i + 1) < *(data + i)){
int t = *(data + i + 1);
*(data + i + 1) = *(data + i);
*(data + i) = t;
}
}
}
void main()
{
int data[5]={4,3,2,1,0};
int i;
bubble_a(data,5);
for(i=0;i<5;i++)
{
printf("%2d
",data[i]);
}
}
运行结果：
B、书写并测试一个由这个函数和测试代码组成的Y86-64程序。
.file "sort.c"
.text
.globl bubble_a
.type bubble_a, @function
bubble_a:
.LFB0:
.cfi_startproc
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset 6, -16
movq %rsp, %rbp
.cfi_def_cfa_register 6
movq %rdi, -24(%rbp)
movl %esi, -28(%rbp)
movl $1, -8(%rbp)
jmp .L2
.L6:
movl -8(%rbp), %eax
subl $1, %eax
movl %eax, -12(%rbp)
jmp .L3
.L5:
movl -12(%rbp), %eax
cltq
addq $1, %rax
leaq 0(,%rax,4), %rdx
movq -24(%rbp), %rax
addq %rdx, %rax
movl (%rax), %edx
movl -12(%rbp), %eax
cltq
leaq 0(,%rax,4), %rcx
movq -24(%rbp), %rax
addq %rcx, %rax
movl (%rax), %eax
cmpl %eax, %edx
jge .L4
movl -12(%rbp), %eax
cltq
addq $1, %rax
leaq 0(,%rax,4), %rdx
movq -24(%rbp), %rax
addq %rdx, %rax
movl (%rax), %eax
movl %eax, -4(%rbp)
movl -12(%rbp), %eax
cltq
addq $1, %rax
leaq 0(,%rax,4), %rdx
movq -24(%rbp), %rax
addq %rax, %rdx
movl -12(%rbp), %eax
cltq
leaq 0(,%rax,4), %rcx
movq -24(%rbp), %rax
addq %rcx, %rax
movl (%rax), %eax
movl %eax, (%rdx)
movl -12(%rbp), %eax
cltq
leaq 0(,%rax,4), %rdx
movq -24(%rbp), %rax
addq %rax, %rdx
movl -4(%rbp), %eax
movl %eax, (%rdx)
.L4:
subl $1, -12(%rbp)
.L3:
cmpl $0, -12(%rbp)
jns .L5
addl $1, -8(%rbp)
.L2:
movl -8(%rbp), %eax
cmpl -28(%rbp), %eax
jl .L6
nop
popq %rbp
.cfi_def_cfa 7, 8
ret
.cfi_endproc
.LFE0:
.size bubble_a, .-bubble_a
.section .rodata
.LC0:
.string "%2d
"
.text
.globl main
.type main, @function
main:
.LFB1:
.cfi_startproc
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset 6, -16
movq %rsp, %rbp
.cfi_def_cfa_register 6
subq $48, %rsp
movq %fs:40, %rax
movq %rax, -8(%rbp)
xorl %eax, %eax
movl $4, -32(%rbp)
movl $3, -28(%rbp)
movl $2, -24(%rbp)
movl $1, -20(%rbp)
movl $0, -16(%rbp)
leaq -32(%rbp), %rax
movl $5, %esi
movq %rax, %rdi
call bubble_a
movl $0, -36(%rbp)
jmp .L8
.L9:
movl -36(%rbp), %eax
cltq
movl -32(%rbp,%rax,4), %eax
movl %eax, %esi
movl $.LC0, %edi
movl $0, %eax
call printf
addl $1, -36(%rbp)
.L8:
cmpl $4, -36(%rbp)
jle .L9
nop
movq -8(%rbp), %rax
xorq %fs:40, %rax
je .L10
call __stack_chk_fail
.L10:
leave
.cfi_def_cfa 7, 8
ret
.cfi_endproc
.LFE1:
.size main, .-main
.ident "GCC: (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609"
.section .note.GNU-stack,"",@progbits
X86-64机器码：
Y86-64
bubble_c:
.LFB22:
.cfi_startproc
pushl %edi
.cfi_def_cfa_offset 8
.cfi_offset 7, -8
pushl %esi
.cfi_def_cfa_offset 12
.cfi_offset 6, -12
pushl %ebx
.cfi_def_cfa_offset 16
.cfi_offset 3, -16
mrmovl 16(%esp), %edx
mrmovl 20(%esp), %edi
irmovl $1, %eax
subl %eax, %edi
jle .L1
subl $1, %edi
irmovl $0, %esi
.L6:
rrmovl %esi, %eax
irmovl $0 , ebx
subl %ebx, %esi
jl .L3
.L7:
rrmovl %eax, %ecx
addl %ecx, %ecx
addl %ecx, %ecx
addl %edx, %ecx
mrmovl 4(%ecx), %ecx
rrmovl %eax, %ebx
addl %ecx, %ebx
addl %ecx, %ebx
addl %edx, %ebx
mrmovl (%ebx), %ebx
subl %ebx, %ecx
jge .L4
addl %eax, %eax
addl %eax, %eax
addl %edx, %eax
rmmovl %ebx, 4(%eax)
addl %eax, %eax
addl %eax, %eax
addl %edx, %eax
rmmovl %ecx, 4(%eax)
.L4:
subl $1, %eax
irmovl $-1, %edx
subl %edx, %eax
jne .L7
.L3:
addl $1, %esi
subl %edi, %esi
jne .L6
.L1:
popl %ebx
.cfi_def_cfa_offset 12
.cfi_restore 3
popl %esi
.cfi_def_cfa_offset 8
.cfi_restore 6
popl %edi
.cfi_def_cfa_offset 4
.cfi_restore 7
ret
.cfi_endproc
.LFE22:
.size bubble_c, .-bubble_c
.section .rodata.str1.1,"aMS",@progbits,1
4.48
实现排序，3次条件传送。
void bubble_c(int *data,int count)
{
int i , next;
int pre_ele,next_ele;
for(next = 1;next < count;next++)
{
for(i = next -1;i >= 0;i--)
{
pre_ele = *(data + i);
next_ele = *(data + i + 1);
*(data + i) = next_ele < pre_ele ? next_ele : pre_ele;//三目运算符号
*(data + i + 1) = next_ele < pre_ele ? pre_ele : next_ele;//使用两次条件传送
}
}
}
X86-64汇编：
X86-64机器码：
**Y86-64汇编：
bubble_b:
.LFB22:
.cfi_startproc
pushl %edi
.cfi_def_cfa_offset 8
.cfi_offset 7, -8
pushl %esi
.cfi_def_cfa_offset 12
.cfi_offset 6, -12
pushl %ebx
.cfi_def_cfa_offset 16
.cfi_offset 3, -16
mrmovl 16(%esp), %edx
mrmovl 20(%esp), %edi
irmovl $1, %eax
subl %eax, %edi
jle .L1
subl $1, %edi
irmovl $0, %esi
.L6:
movl (%ebx,%eax,4), %edx
movl 4(%ebx,%eax,4), %ecx
cmpl %edx, %ecx
movl %edx, %ebp
cmovle %ecx, %ebp
movl %ebp, (%ebx,%eax,4)
cmovge %ecx, %edx
movl %edx, 4(%ebx,%eax,4)
subl $1, %eax
cmpl $-1, %eax
jne .L6
.L7:
rrmovl %eax, %ecx
addl %ecx, %ecx
addl %ecx, %ecx
addl %edx, %ecx
mrmovl 4(%ecx), %ecx
rrmovl %eax, %ebx
addl %ecx, %ebx
addl %ecx, %ebx
addl %edx, %ebx
mrmovl (%ebx), %ebx
subl %ebx, %ecx
jge .L4
addl %eax, %eax
addl %eax, %eax
addl %edx, %eax
rmmovl %ebx, 4(%eax)
addl %eax, %eax
addl %eax, %eax
addl %edx, %eax
rmmovl %ecx, 4(%eax)
.L4:
subl $1, %eax
irmovl $-1, %edx
subl %edx, %eax
jne .L7
.L3:
addl $1, %esi
subl %edi, %esi
jne .L6
.L1:
popl %ebx
.cfi_def_cfa_offset 12
.cfi_restore 3
popl %esi
.cfi_def_cfa_offset 8
.cfi_restore 6
popl %edi
.cfi_def_cfa_offset 4
.cfi_restore 7
ret
.cfi_endproc
.LFE22:
.size bubble_b, .-bubble_b
4.49
实现冒泡排序，要求不使用跳转，且最多使用1次条件传送。
void bubble_c(int *data,int count)
{
int i , next;
int pre_ele,next_ele;
for(next = 1;next < count;next++)
{
for(i = next -1;i >= 0;i--)
{
pre_ele = *(data + i);
next_ele = *(data + i + 1);
*(data + i) = next_ele < pre_ele ? next_ele : pre_ele;
*(data + i + 1) = pre_ele;
}
}
}
X86-64汇编：
X86-64机器码：
**Y86-64汇编：
bubble_b:
.LFB22:
.cfi_startproc
pushl %edi
.cfi_def_cfa_offset 8
.cfi_offset 7, -8
pushl %esi
.cfi_def_cfa_offset 12
.cfi_offset 6, -12
pushl %ebx
.cfi_def_cfa_offset 16
.cfi_offset 3, -16
mrmovl 16(%esp), %edx
mrmovl 20(%esp), %edi
irmovl $1, %eax
subl %eax, %edi
jle .L1
subl $1, %edi
irmovl $0, %esi
.L6:
movl (%ebx,%eax,4), %edx
movl 4(%ebx,%eax,4), %ecx
cmpl %edx, %ecx
movl %edx, %ebp
cmovle %ecx, %ebp
movl %edx, 4(%ebx,%eax,4)
subl $1, %eax
cmpl $-1, %eax
jne .L6
.L7:
rrmovl %eax, %ecx
addl %ecx, %ecx
addl %ecx, %ecx
addl %edx, %ecx
mrmovl 4(%ecx), %ecx
rrmovl %eax, %ebx
addl %ecx, %ebx
addl %ecx, %ebx
addl %edx, %ebx
mrmovl (%ebx), %ebx
subl %ebx, %ecx
jge .L4
addl %eax, %eax
addl %eax, %eax
addl %edx, %eax
rmmovl %ebx, 4(%eax)
addl %eax, %eax
addl %eax, %eax
addl %edx, %eax
rmmovl %ecx, 4(%eax)
.L4:
subl $1, %eax
irmovl $-1, %edx
subl %edx, %eax
jne .L7
.L3:
addl $1, %esi
subl %edi, %esi
jne .L6
.L1:
popl %ebx
.cfi_def_cfa_offset 12
.cfi_restore 3
popl %esi
.cfi_def_cfa_offset 8
.cfi_restore 6
popl %edi
.cfi_def_cfa_offset 4
.cfi_restore 7
ret
.cfi_endproc
.LFE22:
.size bubble_b, .-bubble_b
.section .rodata.str1.1,"aMS",@progbits,1