DMD 1.034 and 2.018 releases

[JAnderson]

Christopher Wright wrote:
> bearophile wrote:
>> Walter Bright:
>>> Can you make it faster?
>>
>> Lot of people today have 2 (or even 4 cores), the order of the 
>> computation of those ops is arbitrary, so a major (nearly linear, 
>> hopefully) speedup will probably come as soon all the cores are used. 
>> This job splitting is probably an advantage even then the ops aren't 
>> computed by asm code.
> 
> The overhead of creating a new thread for this would be significant. 
> You'd probably be better off using a regular loop for arrays that are 
> not huge.

I agree.  I think a lot of profiling would be in order to see when 
certain things become an advantage to use.  Then use a branch to jump to 
the best algorithm for the particular case (platform + length of array). 
  Hopefully the compiler could inline the algorithm so that constant 
sized arrays don't pay for the additional overhead.

There would be a small cost for the extra branch for small dynamic 
arrays.  Ideally one could  argue that if this becomes a performance 
bottleneck then the program is doing a lot of operations on lots of 
small arrays.  The user could change the design to group their small 
arrays into a larger array to get the performance they desire.

-Joel