DMD backend generation future with the new AI race processor

[Walter Bright]

On 3/10/2024 5:40 PM, Richard (Rikki) Andrew Cattermole wrote:
> Even with Walter working full time on it for a few years, that backend will 
> never match what LLVM 19 can do without things like that.

I regularly have people telling me what I can't do :-)

For example, people in this forum used to tell me that DMD didn't do Data Flow 
Analysis and DFA had been invented in the 2000s.

Never mind that Datalight C circa 1985 was the very first DOS compiler to do DFA.

I was told the backend couldn't do loop unrolling which was a special magical 
thing that only super advanced engineers could write, which it now does.

Then I was told the backend couldn't do SROA, which it does now.

Then I was told the backend couldn't do SIMD, which it does now.

And so on.

It just takes time to do these things, and I'm pretty booked. The DMD backend is 
doing remarkably well considering how little time I spend on it.

Just recently the imminent demise of it was predicted because it wasn't 
generating IBT (Indirect Branch Tracking) code. It generates IBT now.