近来碰到了一个很奇怪的问题，switch语句竟然能编译出除数为0的情况，而且进入到除数为0错误里面出不来了！！以下是C和编译出来的汇编程序，有没有高手碰到过类似的问题？？
C程序：
void User_28_Key(uint8 keyvalue)
{
uint32 temp;
switch(keyvalue)
{
case LEFT:if((pPage.ColorFlag==0)||(pPage.ColorFlag==1))
pPage.ColorFlag = 9;
else
pPage.ColorFlag--;
break;
case RIGHT:if(pPage.ColorFlag==9)
pPage.ColorFlag = 1;
else
pPage.ColorFlag++;
break;
case UP: if(pPage.ColorFlag==0)
{
pPage.CurrentPage--;
pPage.NumFlag = 0;
}
else
{
temp = Pow[9-pPage.ColorFlag];
if(Diandu[pPage.NumFlag]/temp%10==0)
Diandu[pPage.NumFlag] += 9*temp;
else
Diandu[pPage.NumFlag] -= temp;
}
break;
case DOWN:if(pPage.ColorFlag==0)
{
pPage.CurrentPage = USER_NO+1;
pPage.NumFlag = 0;
}
else
{
temp = Pow[9-pPage.ColorFlag];
if(Diandu[pPage.NumFlag]/temp%10==9)
Diandu[pPage.NumFlag] -= 9*temp;
else
Diandu[pPage.NumFlag] += temp;
}
break;
case ESC: pPage.PrePage = pPage.CurrentPage;
pPage.CurrentPage = OTHER_NO;
pPage.NumFlag = 0;
pPage.ColorFlag = 0;
break;
case ENTER:if(pPage.NumFlag==7)
pPage.NumFlag = 0;
else
pPage.NumFlag++;
pPage.ColorFlag = 0 ;
break;
default: break;
}
}
以下是编译出来的汇编程序：
[0xe92d4ff8] stmfd r13!,{r3-r11,r14}
[0xe59f9660] ldr r9,0x800199c0 ; = #0x8003b498
[0xe59f9660] ldr r9,0x800199c4 ; = #0x8101329e
[0xe596500c] ldr r5,[r6,#0xc]
[0xe1a0b000] mov r11,r0
[0xe59fa650] ldr r10,0x800199c0 ; = #0x8003b498
[0xe5964008] ldr r4,[r6,#8]
[0xe2658009] rsb r8,r5,#9
[0xe7990108] ldr r0,[r9,r8,lsl #2]
[0xeb000757] bl __rt_udiv （1）
[0xeb000757] bl 0x8001b0e0 ; (__rt_udiv + 0x4) （2）
[0xeb000796] bl 0x8001b1e0 ; (__rt_udiv10 + 0x4) （3）
[0xe1a07001] mov r7,r1
[0xe3a01000] mov r1,#0
[0xe5960000] ldr r0,[r6,#0]
[0xe35b0006] cmp r11,#6
[0x908ff10b] addls pc,pc,r11,lsl #2
[0xea00000b] b 0x800193cc ; (User_28_Key + 0x7c)
[0xea00000b] b 0x800193d0 ; (User_28_Key + 0x80)
[0xea000004] b 0x800193b8 ; (User_28_Key + 0x68)
[0xea00000d] b 0x800193e0 ; (User_28_Key + 0x90)
[0xea00003a] b 0x80019498 ; (User_28_Key + 0x148)
[0xea00003f] b 0x800194b0 ; (User_28_Key + 0x160)
[0xea000012] b 0x80019400 ; (User_28_Key + 0xb0)
[0xea000024] b 0x8001944c ; (User_28_Key + 0xfc)
[0x0a000001] beq 0x800193c4 ; (User_28_Key + 0x74)
[0x0a000001] beq 0x800193c8 ; (User_28_Key + 0x78)
[0xe3550001] cmp r5,#1
[0x1a000002] bne 0x800193d4 ; (User_28_Key + 0x84)
[0xe3a00009] mov r0,#9
[0xe586000c] str r0,[r6,#0xc]
[0xe8bd8ff8] ldmfd r13!,{r3-r11,pc}
[0xe2450001] sub r0,r5,#1
[0xeafffffb] b 0x800193cc ; (User_28_Key + 0x7c)
[0xeafffffb] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe3550009] cmp r5,#9
[0x1a000002] bne 0x800193f4 ; (User_28_Key + 0xa4)
[0xe3a00001] mov r0,#1
[0xe586000c] str r0,[r6,#0xc]
[0xeafffff6] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe2850001] add r0,r5,#1
[0xeafffff3] b 0x800193cc ; (User_28_Key + 0x7c)
[0xeafffff3] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe3550000] cmp r5,#0
[0x1a000003] bne 0x80019418 ; (User_28_Key + 0xc8)
[0xe2400001] sub r0,r0,#1
[0xe5860000] str r0,[r6,#0]
[0xe5861008] str r1,[r6,#8]
[0xeaffffed] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe79a6104] ldr r6,[r10,r4,lsl #2]
[0xe79a6104] ldr r6,[r10,r4,lsl #2]
[0xe1a00005] mov r0,r5
[0xeb0006c4] bl 0x8001af3c ; (__rt_divtest + 0x4)
[0xe3570000] cmp r7,#0
[0x1a000003] bne 0x80019440 ; (User_28_Key + 0xf0)
[0xe0850185] add r0,r5,r5,lsl #3
[0xe0860000] add r0,r6,r0
[0xeaffffe3] b 0x800193cc ; (User_28_Key + 0x7c)
[0xeaffffe3] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe0460005] sub r0,r6,r5
[0xe78a0104] str r0,[r10,r4,lsl #2]
[0xeaffffe0] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe3550000] cmp r5,#0
[0x1a000003] bne 0x80019464 ; (User_28_Key + 0x114)
[0xe3a00010] mov r0,#0x10
[0xe5861008] str r1,[r6,#8]
[0xe5861008] str r1,[r6,#8]
[0xeaffffda] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe7995108] ldr r5,[r9,r8,lsl #2]
[0xe79a6104] ldr r6,[r10,r4,lsl #2]
[0xe1a00005] mov r0,r5
[0xeb0006b1] bl 0x8001af3c ; (__rt_divtest + 0x4)
[0xe3570009] cmp r7,#9
[0xe0850185] add r0,r5,r5,lsl #3
[0xe0850185] add r0,r5,r5,lsl #3
[0xe0460000] sub r0,r6,r0
[0xe78a0104] str r0,[r10,r4,lsl #2]
[0xeaffffd0] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe0860005] add r0,r6,r5
[0xe78a0104] str r0,[r10,r4,lsl #2]
[0xeaffffcd] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe3a0003f] mov r0,#0x3f
[0xe3a0003f] mov r0,#0x3f
[0xe5860000] str r0,[r6,#0]
[0xe5861008] str r1,[r6,#8]
[0xe586100c] str r1,[r6,#0xc]
[0xeaffffc7] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe3540008] cmp r4,#8
[0x1a000001] bne 0x800194c0 ; (User_28_Key + 0x170)
[0xea000001] b 0x800194c4 ; (User_28_Key + 0x174)
[0xea000001] b 0x800194c8 ; (User_28_Key + 0x178)
[0xe2840001] add r0,r4,#1
[0xe5860008] str r0,[r6,#8]
[0xe586100c] str r1,[r6,#0xc]
[0xeaffffbf] b 0x800193d0 ; (User_28_Key + 0x80)
[0xe92d4070] stmfd r13!,{r4-r6,r14}
[0xe51feaac] ldr r14,0x80018a30 ; = #0x000001b6
[0xe59e000c] ldr r0,[r14,#0xc]
[0xe59e000c] ldr r0,[r14,#0xc]
[0xe3e01003] mvn r1,#3
[0xe59f44dc] ldr r4,0x800199c8 ; = #0x00000313
[0xe0812100] add r2,r1,r0,lsl #2
[0xe1d410b0] ldrh r1,[r4,#0]
[0xe3a05001] mov r5,#1
[0xe1a03215] mov r3,r5,lsl r2
[0xe1a0c231] mov r12,r1,lsr r2
[0xe1a0c231] mov r12,r1,lsr r2
[0x908ff106] addls pc,pc,r6,lsl #2
怎么会编译出（1），（2），（3）这三步呢？？还有几个函数跟上述函数类似，都没有这样的问题，就这个函数是这样的，真的很奇怪，左看右看，都没有什么问题啊，找了一两天了，高手请赐教！！
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