Re: Optimize away immediately-called delegate literals?

[Steven Schveighoffer]

On Mon, 12 Mar 2012 20:28:15 -0400, H. S. Teoh <hst...@quickfur.ath.cx>  
wrote:


Hmph.

I tried this code:

        import std.stdio;
        struct A {
                int[] data;
                int opApply(int delegate(ref int) dg) {
                        foreach (d; data) {
                                if (dg(d)) return 1;
                        }
                        return 0;
                }
        }
        void main() {
                A a;
                int n = 0;

                a.data = [1,2,3,4,5];
                foreach (d; a) {
                        n++;
                }
        }

With both dmd and gdc, the delegate is never inlined. :-(  Compiling
with gdc -O3 causes opApply to get inlined and loop-unrolled, but the
call to the delegate is still there. With dmd -O, even opApply is not
inlined, and the code is generally much longer per loop iteration than
gdc -O3.

IIRC, ldc does inline opApply.  But this is somewhat hearsay since I don't  
use ldc.  I'm just remembering what others have posted here.

-Steve