On 2/25/2016 3:06 PM, H. S. Teoh via Digitalmars-d wrote:
I remember you did a bunch of stuff to the optimizer after the switchover to self-hosting; how much of a difference did that make? Are there any low-hanging fruit left that could make dmd faster?
There's a lot of low hanging fruit in dmd. In particular, far too many templates are instantiated over and over.
The data structures need to be looked at, and the excessive memory consumption also slows things down.
On a related note, I discovered an O(n^2) algorithm in the front-end... it's unlikely to be an actual bottleneck in practice (basically it's quadratic in the number of fields in an aggregate), though you never know. It actually does a full n^2 iterations, and seemed like it could be at least pared down to n(n+1)/2, even without doing better than O(n^2).
Please add a comment to the source code about this and put it in a PR.
