Normal programming question

[Guest]

I got two questions about the programming of PIC16F877.
1. Normally, when we rotate 8 time with 8 bit data, we will get back the same data right? But if I rotate one time, then call a subroutine or goto other place, the carry flag already change. Then back to here and rotate again. This loop will go on for 8 time, is it finally still can get back the same data?
2. If I add 8 bit data with another 8 bit data and the result is is overload to 9 or 10 bit, then how a result will store?