On Fri, 25 Mar 2011 22:04:20 -0400, Caligo <[email protected]> wrote:
T[3] data; T dot(const ref Vector o){return data[0] * o.data[0] + data[1] * o.data[1] + data[2] * o.data[2];} T LengthSquared_Fast(){ return data[0] * data[0] + data[1] * data[1] + data[2] * data[2]; } T LengthSquared_Slow(){ return dot(this); } The faster LengthSquared() is twice as fast, and I've test with GDC and DMD. Is it because the compilers don't inline-expand the dot() function call? I need the performance, but the faster version is too verbose.
ref parameters used to make functions not be inlined, but apparently that was fixed: http://d.puremagic.com/issues/show_bug.cgi?id=2008
The best thing to do is check the disassembly to see if the call is being inlined.
Also, if you want more help besides guessing, a complete working program is good to have.
-Steve
