我目前正在为Java的一个子集编写一个编译器，并且可以将代码转换为x86 32位汇编。我已经能够编写一些程序了，但是下面的程序给我带来了麻烦：
class DummySort {
public static void main(String[] a){
DS ds = new DS();
ds.Start(12);
}
}
// This class contains the array of integers and
// methods to initialize, print and sort the array
class DS{
int[] number ;
int size ;
// Invoke the Initialization, Sort and Printing
// Methods
public void Start(int sz){
int aux01 ;
aux01 = this.Init(sz);
System.out.printf("%s\n","----- UNSORTED -----");
this.Print("U");
}
// Print array of integers
public void Print(String s){
int j = 0;
int n = 0;
while (j < (size)) {
//Switching prints change behavior
System.out.printf("%d at %d with %s\n",number[j],j,s);
n = j;
j = j + 1 ;
//System.out.printf("%d at %d with %s\n",number[n],n,s);
}
}
// Initialize array of integers
public int Init(int sz){
size = sz ;
number = new int[sz] ;
number[0] = 20 ;
number[1] = 7 ;
number[2] = 12 ;
number[3] = 18 ;
number[4] = 2 ;
number[5] = 11 ;
number[6] = 6 ;
number[7] = 9 ;
number[8] = 19 ;
number[9] = 5 ;
number[10] = 25;
number[11] = 0;
return 0 ;
}
}
主要问题来自于切换使用哪个print语句。第一个结果是无限循环打印：
7 at 1 with U
使用第二个打印而不是第一个打印产生以下内容并终止：
----- UNSORTED -----
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
2 at 4 with U
这是我的程序在上述情况下生成的程序集：
.file "DummySort.s"
.section .rodata
STR0:
.ascii "%d at %d with %s\12\0"
STR1:
.ascii "%s\12\0"
STR2:
.ascii "----- UNSORTED -----\0"
STR3:
.ascii "U\0"
.text
#CODEBLOCK: prog: 0
#CODEBLOCK: DS
#CODEBLOCK: DS:new
DS_new:
pushl %ebp
movl %esp, %ebp
#CODEBLOCK: save
pushl %edx
pushl %ebx
pushl %ecx
pushl %esi
#END_BLOCK: save
pushl $8
call _malloc
addl $4, %esp
#CODEBLOCK: restore
popl %esi
popl %ecx
popl %ebx
popl %edx
#END_BLOCK: restore
movl %eax, %esi
#CODEBLOCK: varDec: 14
movl $0, (%esi)
#END_BLOCK: varDec: 14
#CODEBLOCK: varDec: 18
movl $0, 4(%esi)
#END_BLOCK: varDec: 18
movl %esi, %eax
movl %ebp, %esp
popl %ebp
ret
#END_BLOCK: DS:new
#CODEBLOCK: DS:Methods: 0
#CODEBLOCK: DS:Start
DS_Start:
pushl %ebp
movl %esp, %ebp
#CODEBLOCK: varDec: 20
movl $0, -4(%ebp)
#END_BLOCK: varDec: 20
#CODEBLOCK: assignStat: 21
#CODEBLOCK: save
pushl %edx
pushl %ebx
pushl %ecx
pushl %esi
#END_BLOCK: save
#CODEBLOCK: call
pushl 8(%ebp)
call DS_Init
addl $4, %esp
#END_BLOCK: call
#CODEBLOCK: restore
popl %esi
popl %ecx
popl %ebx
popl %edx
#END_BLOCK: restore
movl %eax, %edx
movl %edx, -4(%ebp)
#END_BLOCK: assignStat: 21
#CODEBLOCK: funcStat: 22
#CODEBLOCK: save
pushl %edx
pushl %ebx
pushl %ecx
pushl %esi
#END_BLOCK: save
#CODEBLOCK: call
pushl $STR2
pushl $STR1
call _printf
addl $8, %esp
#END_BLOCK: call
#CODEBLOCK: restore
popl %esi
popl %ecx
popl %ebx
popl %edx
#END_BLOCK: restore
#END_BLOCK: funcStat: 22
#CODEBLOCK: funcStat: 23
#CODEBLOCK: save
pushl %edx
pushl %ebx
pushl %ecx
pushl %esi
#END_BLOCK: save
#CODEBLOCK: call
pushl $STR3
call DS_Print
addl $4, %esp
#END_BLOCK: call
#CODEBLOCK: restore
popl %esi
popl %ecx
popl %ebx
popl %edx
#END_BLOCK: restore
#END_BLOCK: funcStat: 23
movl %ebp, %esp
popl %ebp
ret
#END_BLOCK: DS:Start
#CODEBLOCK: DS:Print
DS_Print:
pushl %ebp
movl %esp, %ebp
#CODEBLOCK: varDec: 28
movl $0, -4(%ebp)
#END_BLOCK: varDec: 28
#CODEBLOCK: varDec: 29
movl $0, -8(%ebp)
#END_BLOCK: varDec: 29
#CODEBLOCK: whileStat: 36
WHILE1:
movl -4(%ebp), %edx
xor %eax, %eax
cmp 4(%esi), %edx
setl %al
movl %eax, %edx
cmp $0, %edx
je ENDWHILE1
#CODEBLOCK: blockStat: 36
#CODEBLOCK: funcStat: 32
#CODEBLOCK: save
pushl %edx
pushl %ebx
pushl %ecx
pushl %esi
#END_BLOCK: save
#CODEBLOCK: call
pushl 8(%ebp)
pushl -4(%ebp)
movl -4(%ebp), %edx
movl (%esi), %ebx
pushl (%ebx,%edx,4)
pushl $STR0
call _printf
addl $16, %esp
#END_BLOCK: call
#CODEBLOCK: restore
popl %esi
popl %ecx
popl %ebx
popl %edx
#END_BLOCK: restore
#END_BLOCK: funcStat: 32
#CODEBLOCK: assignStat: 33
movl -4(%ebp), %eax
movl %eax, -8(%ebp)
#END_BLOCK: assignStat: 33
#CODEBLOCK: assignStat: 35
movl -4(%ebp), %edx
addl $1, %edx
movl %edx, -4(%ebp)
#END_BLOCK: assignStat: 35
#END_BLOCK: blockStat: 36
jmp WHILE1
ENDWHILE1:
#END_BLOCK: whileStat: 36
movl %ebp, %esp
popl %ebp
ret
#END_BLOCK: DS:Print
#CODEBLOCK: DS:Init
DS_Init:
pushl %ebp
movl %esp, %ebp
#CODEBLOCK: assignStat: 41
movl 8(%ebp), %eax
movl %eax, 4(%esi)
#END_BLOCK: assignStat: 41
#CODEBLOCK: assignStat: 43
movl 8(%ebp), %edx
imul $4, %edx
#CODEBLOCK: save
pushl %edx
pushl %ebx
pushl %ecx
pushl %esi
#END_BLOCK: save
pushl %edx
call _malloc
addl $4, %esp
#CODEBLOCK: restore
popl %esi
popl %ecx
popl %ebx
popl %edx
#END_BLOCK: restore
movl %eax, %edx
movl %edx, (%esi)
#END_BLOCK: assignStat: 43
#CODEBLOCK: arrAssignStat: 44
movl $20, %edx
movl $0, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 44
#CODEBLOCK: arrAssignStat: 45
movl $7, %edx
movl $1, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 45
#CODEBLOCK: arrAssignStat: 46
movl $12, %edx
movl $2, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 46
#CODEBLOCK: arrAssignStat: 47
movl $18, %edx
movl $3, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 47
#CODEBLOCK: arrAssignStat: 48
movl $2, %edx
movl $4, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 48
#CODEBLOCK: arrAssignStat: 49
movl $11, %edx
movl $5, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 49
#CODEBLOCK: arrAssignStat: 50
movl $6, %edx
movl $6, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 50
#CODEBLOCK: arrAssignStat: 51
movl $9, %edx
movl $7, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 51
#CODEBLOCK: arrAssignStat: 52
movl $19, %edx
movl $8, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 52
#CODEBLOCK: arrAssignStat: 53
movl $5, %edx
movl $9, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 53
#CODEBLOCK: arrAssignStat: 54
movl $25, %edx
movl $10, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 54
#CODEBLOCK: arrAssignStat: 55
movl $0, %edx
movl $11, %ebx
movl (%esi), %ecx
movl %edx, (%ecx,%ebx,4)
#END_BLOCK: arrAssignStat: 55
#CODEBLOCK: returnStat: 56
movl $0, %eax
movl %ebp, %esp
popl %ebp
ret
#END_BLOCK: returnStat: 56
#END_BLOCK: DS:Init
#END_BLOCK: DS:Methods: 0
#END_BLOCK: DS
#CODEBLOCK: _main
.globl _main
_main:
#CODEBLOCK: mainPre
pushl %ebp
movl %esp, %ebp
#END_BLOCK: mainPre
#CODEBLOCK: mMtdLocs
subl $4, %esp
#END_BLOCK: mMtdLocs
#CODEBLOCK: varDec: 4
#CODEBLOCK: save
pushl %edx
pushl %ebx
pushl %ecx
pushl %esi
#END_BLOCK: save
call DS_new
#CODEBLOCK: restore
popl %esi
popl %ecx
popl %ebx
popl %edx
#END_BLOCK: restore
movl %eax, %edx
movl %edx, -4(%ebp)
#END_BLOCK: varDec: 4
#CODEBLOCK: funcStat: 5
#CODEBLOCK: save
pushl %edx
pushl %ebx
pushl %ecx
pushl %esi
#END_BLOCK: save
#CODEBLOCK: call
pushl $12
movl -4(%ebp), %esi
call DS_Start
addl $4, %esp
#END_BLOCK: call
#CODEBLOCK: restore
popl %esi
popl %ecx
popl %ebx
popl %edx
#END_BLOCK: restore
#END_BLOCK: funcStat: 5
#CODEBLOCK: mainEnd
movl $0, %eax
movl %ebp, %esp
popl %ebp
ret
#END_BLOCK: mainEnd
#END_BLOCK: _main
#END_BLOCK: prog: 0
我一直在看这段代码几个小时，非常感谢任何帮助。我可以发布在第二种情况下生成的程序集，但除了代码块的定位外，它似乎完全相同。
如果有人要求提供更多生成的示例，请告诉我并再次感谢！
答案 0 :(得分：1)
在Start和Print中，您不会从堆栈中为本地人分配空间。 IE浏览器。你错过了sub $x, %esp。因此，你的推送和电话将覆盖当地人，造成严重破坏。
$ ./a.out
----- UNSORTED -----
20 at 0 with U
7 at 1 with U
12 at 2 with U
18 at 3 with U
2 at 4 with U
11 at 5 with U
6 at 6 with U
9 at 7 with U
19 at 8 with U
5 at 9 with U
25 at 10 with U
0 at 11 with U
耶！ \ O /