search for: level1_dcache_linesize

...++ standards. > > I still think there's some weird library out there that interprets it > the way you're suggesting, and Clang is not that weird library. This is from a famous article series titled "What every programmer should know about memory": gcc -DCLS=$(getconf LEVEL1_DCACHE_LINESIZE) ... https://lwn.net/Articles/255364/ http://mosermichael.github.io/cstuff/all/blog/2015/12/11/wepskn.html https://www.dcl.hpi.uni-potsdam.de/teaching/numasem/slides/NUMASem_Matrix_multiplication.pdf You can find more examples by searching for "DCLS getconf LEVEL1_DCACHE_LINESIZE".

On Tue, 19 Jun 2018 at 20:46, Bruce Hoult <brucehoult at sifive.com> wrote: > Furthermore .. in the articles you reference, the -DCLS=$(getconf LEVEL1_DCACHE_LINESIZE) is passed when compiling the user's program -- one doing extensive blocked matrix operations -- and not when building the *compiler*. It's worse. At least in the first case, the code looks like it wouldn't even compile without that definition. That's not an optimization flag, that...

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...

Tim Northover via llvm-dev wrote on 06/19/2018 07:55 PM: > On Tue, 19 Jun 2018 at 18:22, U.Mutlu via llvm-dev > <llvm-dev at lists.llvm.org> wrote: >> I think such "reserved" names like CLS that can be passed to the compiler(s), >> should be avoided as identifiers for naming variables, constants, enum >> members, macros etc. > > Why are you passing