Displaying 2 results from an estimated 2 matches for "flagomancy".
2018 Jun 19
2
Naming clash: -DCLS=n and CLS in code
Tim Northover via llvm-dev wrote on 06/19/2018 09:22 PM:
> On Tue, 19 Jun 2018 at 20:12, U.Mutlu <um at mutluit.com> wrote:
>> You can find more examples by searching for "DCLS getconf LEVEL1_DCACHE_LINESIZE".
>
> Frankly, it all looks like cargo-cult optimization flagomancy. I'd
> suggest you drop it, it's not magical I promise.
Hey, I'm working on optimization, and I know "it works".
Curious, have you ever heard of "false sharing" and "true sharing"
and what lies behind them?
Hint: it has todo with the cacheline and its...
2018 Jun 19
6
Naming clash: -DCLS=n and CLS in code
Tim Northover wrote on 06/19/2018 08:54 PM:
>>> Why are you passing that argument in the first place? The compiler
>>> completely ignores it.
>>
>> CLS stands for cacheline size. It is an important parameter
>> for optimization of the generated code, at least with gcc/g++.
>> -DCLS=n should have the same importance like for example -DNDEBUG.
>
> The