Code optimization of inner loop

[Eli Horn]

Dear all,

I would appriciate any input you may have on how to optimize this line which appears in my most inner loop:

*pG=(short)(((i nt)w1*V1+w2*V2+ w3*V3+w4*V4)/(w1+w2+w3+w4));

w1,w2,w3,w4,V1, V2,V3,V4 are all short and the result is also short.
If it makes any difference, all variables are positive and smaller than 4095.

Thanks for any input,
Eli.

[pukur123]

If all the variables are initialised with the value = 4094, the value of

(int)w1*V1+w2*V 2+w3*V3+w4*V4)

will exceed the maximum number that an integer can store and so the result will be a negative one.

So you can change the typecasting to float. Now the statement will become

*pG=(short)(((f loat)w1*V1+w2*V 2+w3*V3+w4*V4)/(w1+w2+w3+w4));

[Eli Horn]

This is not a problem since this case cannot happen.
Let me not bother you with the details but just say that I don't have range problems and my only problem is how to speed up this code.