dmd codegen improvements

[Jonathan M Davis via Digitalmars-d]

On Thursday, 27 August 2015 at 14:12:01 UTC, Bruno Medeiros wrote:
> On 18/08/2015 21:28, Walter Bright wrote:
>> On 8/18/2015 12:38 PM, deadalnix wrote:
>>> And honestly, there is no way DMD can catch up.
>>
>> I find your lack of faith disturbing.
>>
>> https://www.youtube.com/watch?v=Zzs-OvfG8tE&feature=player_detailpage#t=91
>
> My instinct also tells me it's extremely unlikely that DMD will 
> be able to catch. But regardless of that, let's suppose it does 
> catch up, that you (and/or others) are eventually able to make 
> the DMD backend as good as LLVM/GCC. At what cost (development 
> time wise) will that come? How much big chunks of development 
> effort will be spent on that task, that could be spent on 
> improving other areas of D, just so that DMD could be about as 
> good (not better, just *as good*), as LDC/GDC?...

Honestly, while I don't see why dmd couldn't catch up to gdc and 
ldc if enough development time were sunk into it, I seriously 
question that dmd can catch up without way too much development 
time being sunk into it. And if ldc and gdc are ultimately the 
compilers that folks should be using if they want the best 
performance, then so be it. But if dmd can be sped up so that 
it's closer and there's less need to worry about the speed 
difference for most folks, then I think that that's a big win. 
Every little bit of performance improvement that we can get out 
of dmd is an improvement, especially when those improvements come 
at minimal cost, and I see no reason to not improve dmd's 
performance where it's not going to be a huge timesink to do so 
and where the appropriate precautions are taken to avoid 
regressions.

- Jonathan M Davis