On 12/19/10 9:32 AM, Ary Borenszweig wrote:
I have this code:
---
import std.stdio;
int foobar(int delegate(int) f) {
return f(1);
}
int foobar2(string s)() {
int x = 1;
mixin("return " ~ s ~ ";");
}
void main() {
writefln("%d", foobar((int x) { return 2*x; }));
writefln("%d", foobar2!("9876*x"));
}
---
When I compile it with -O -inline I can see with obj2asm that for the first
writefln the delegate is being called. However, for the second it just passes
9876 to writefln.
From this I can say many things:
- It seems that if I want hyper-high performance in my code I must use string
mixins because delegate calls, even if they are very simple and the
functions that uses them are also very simple, are not inlined. This has the
drawback that each call to foobar2 with a different string will generate a
different method in the object file.
You forgot:
writefln("%d", foobar2!((x) { return 2*x; })());
That's a real delegate, not a string, but it will be inlined.
Andrei
