我正在尝试在x86（masm32）中编写冒泡排序。排序不起作用。我已经测试了一些代码，它似乎在比较和交换部分搞砸了。 由于某种原因，比较函数总是为EAX分配2。如果我能弄清楚为什么我可以使程序运作。
提前感谢您的帮助。
.data
aa DWORD 10 DUP(5, 7, 6, 1, 4, 3, 9, 2, 10, 8)
count DWORD 0
; DB 8-bits, DW 16-bit, DWORD 32, WORD 16 BYTE 8
.code ; Tell MASM where the code starts
; «««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««
start: ; The CODE entry point to the program
mov esi, count ;loop count
outer:
inc esi
mov edi, count
cmp esi, 9
je end_loop
inner: ;this loop represents a full pass on the entire array
inc edi
cmp edi, 9 ;after 9 passes goes to outer loop
je outer
compare:
mov eax, [aa + edi * 4h] ;higher indexed one
mov ebx, [aa + edi * 4h - 4h]
;testing print chr$(13,10)
;testing print str$(eax)
;testing print chr$(13, 10)
;testing print str$(ebx)
;testing print chr$(13, 10)
cmp ebx, eax
jg swap
swap:
mov [aa + edi * 4h], eax
mov [aa + edi * 4h + 4], ebx
jmp inner
end_loop:
;print out array elements
sub esi, esi
mov esi, [aa]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 2]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 3]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 4]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 5]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 6]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 7]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 8]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 9]
print str$(esi)
print chr$(" ")
sub esi, esi
exit
; «««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««
end start ; Tell MASM where the program ends
答案 0 :(得分：1)
弄清楚出了什么问题 - 程序中间的打印声明正在记忆中。这是工作类型。感谢大家的帮助！
.data
aa DWORD 10 DUP(5, 7, 6, 1, 4, 3, 9, 2, 10, 8)
count DWORD -1
; DB 8-bits, DW 16-bit, DWORD 32, WORD 16 BYTE 8
.code ; Tell MASM where the code starts
; «««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««
start: ; The CODE entry point to the program
mov esi, count ;loop count
outer:
inc esi
mov edi, count
cmp esi, 10
je end_loop
inner: ;this loop represents a full pass on the entire array
inc edi
cmp edi, 9 ;after 9 passes goes to outer loop
je outer
compare:
mov eax, [aa + edi * 4h]
mov ebx, [aa + edi * 4h + 4] ;want to make this one the higher indexed-one
;print chr$(13,10) These print calls were hosing the memory before.
;print str$(eax)
;print chr$(13, 10)
;print str$(ebx)
;print chr$(13, 10)
cmp eax, ebx
jle inner
swap:
mov [aa + edi * 4h], ebx
mov [aa + edi * 4h + 4], eax
jmp inner
end_loop:
;print out array elements
sub esi, esi
mov esi, [aa]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 2]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 3]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 4]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 5]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 6]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 7]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 8]
print str$(esi)
print chr$(" ")
sub esi, esi
mov esi, [aa + 4h * 9]
print str$(esi)
print chr$(" ")
sub esi, esi
exit
; «««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««««
end start ; Tell MASM where the program ends
答案 1 :(得分：0)
一个明显的问题就在这里：
cmp ebx, eax
jg swap
swap:
mov [aa + edi * 4h], eax
mov [aa + edi * 4h + 4], ebx
jmp inner
这样，如果设置了g标志，它会跳转到交换 - 如果g标志不设置，它会掉到交换状态，所以执行两种方式完全相同的代码。猜测，如果两个项目已经按顺序排列，你想要的东西可能就像jle inner一样跳过交换。
编辑：再看一遍，看起来你有另一个相当明显的问题。让我们考虑像C这样的东西，并使用base作为加载eax（compare）的地址。你（概念上）做：
eax = *base;
ebx = *(base + 4);
然后在swap你做：
*base = eax;
*(base - 4) = ebx;
这显然也是错误的。要交换这两个变量，您需要以下内容：
*base = ebx;
*(base + 4) = eax;