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Use BVS/BCS for fast overflow check with long long

Hi,
I need some long long (64 bit) additions in a fast interrupt code.

After each addition, I need to limit the result to MIN/MAX_INT64 if some overflow occurred.

In assembler, I would use the brach command BVC/BVS to check the overflow flag after the addition - this would be only one additional command, very nice (in normal case, where no overflow occurs).

Is there any way to implement / insert such functionality also in C / C++ code?

I tried to include dspfncts.h, and then check the variable Overflow, but this will add 3 additional assembly lines (to load the value of the overflow bit - it does NOT use the very compact commands BVC/BVS). As I have quite many such additions, this will blow up my code quite a bit.

Is there any possibility to do this overflow check in an efficient way in C/C++?

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