Optimization of algebraic computation

Optimization of algebraic computation

Using mathematica, I can compute the mathematical representation of a
function that I then want to code in C++.
Say I get something like:
f=Log[2*x+3*y]+Sin[4*x+6*y]
It obviously makes sense in that case to do the computation:
temp=2*x+3*y
f=Log[temp]+Sin[2*temp]
Is there a way to get the expression that would reduce the execution time
/ number of operations / size of the expression or any good metric given a
more complex mathematical expression?