help!why not use Rx as loop counter?

I have a problem. I write a function in another c source file not main file, in this function nothing do, and I declare the function as extern. In main function I invoke it 200 times. However, the compiler does not use registerbank as counter. Why?

extern void func1(void);

void func2(void)
{
        unsigned char data i;
        for(i=200;i;i--);
}

main()
{
        unsigned char data i,j;
        for(i=200;i;i--)        // store i in 0x08
        {
                func1();
        }
        for(j=200;j;j--)        // store j in R6
        {
                func2();
        }
}
the assembly code:
C:0x0003    7508C8   MOV      0x08,#TMR2CN(0xC8)
    19:         {
    20:                 func1();
C:0x0006    120025   LCALL    func1(C:0025)
    21:         }
C:0x0009    D508FA   DJNZ     0x08,C:0006
    22:         for(j=200;j;j--)
C:0x000C    7EC8     MOV      R6,#TMR2CN(0xC8)
    23:         {
    24:                 func2();
C:0x000E    120020   LCALL    func2(C:0020)
    25:         }
C:0x0011    DEFB     DJNZ     R6,C:000E