quote:Original post by marijnh
Actually, for functions with really tiny bodies like
inline int multiply(int x, int y){
return x*y;
}
...inline functions *decrease* executable size. Placing x*y directly in the executable is much smaller calling a function.
That''s actually wrong. An inline function will almost invariably increase the size of code. Let''s say the function for multiply takes 7 instructions, and x*y takes 3 instructions (register, mul, store). That means if you put "x*y" in your code 4 times it will take 12 instructions, while if you had used it as a function call takes only 7+3 instructions = 10.
As a side note I feel its generally just about useless to manually inline functions with modern compilers. Optimize for speed and your compiler will generally inline where appropriate. Its just a hint anyways. Profile the compiler optimized code and if it appears that you''re bottle necking from code that could be inlined then see if it helps, otherwise inlining adds significant mess to code and will often provide negligable if any speed.
|My site | Association of Computing Machinery
