I like your detailed example, but wouldn't a slightly kinder but equally optimizing compiler simply add a conditional before the load: if (max > 0) { int

I like your detailed example, but wouldn't a slightly kinder but equally optimizing compiler simply add a conditional before the load: if (max > 0) { int i = max; int tmp = p[0].foo; do { bar += tmp; } while (--i); } I'd even argue the assembly is slightly better when interpreted this way, since branch prediction will tend execute the load or not as appropriate, rather than potentially taking a unnecessary TLB miss for a load that's never used.