Re: [Linuxsampler-devel] patches for arm64

[Christian S. <sch...@li...>]

On Sonntag, 29. September 2019 12:53:18 CEST Maurits Lamers wrote:
> Hi all,
> 
> Using information from this mailinglist and some code I found online I
> managed to compile arm64 linuxsampler packages for Ubuntu 16.04 and 18.04.
> I would like to contribute my changes to the project.
> 
> The arm and arm64-specific changes are in
> https://github.com/mauritslamers/linuxsampler/commit/12f4e447e2498f8c9d1c3f
> 7a98b76e8e697ad479

Well, since the sampler's minimum build requirement is now to have at least a 
C++14 compatible compiler, it is probably time considering to switch to 
std::atomic that was introduced with C++11, and thus starting to get rid of 
all assembly atomic code in the sampler's code base, instead of adding asm 
atomic code for yet another architecture:

https://en.cppreference.com/w/cpp/atomic/atomic

There are four major advantages of using std::atomic: 1. it compiles on all 
systems (OSes) and for all architectures (CPUs), and since that C++ header 
uses compiler extensions for the actual atomicity under the hood (e.g. 
__c11_atomic_store), it is the compiler which would generate the actual atomic 
CPU instructions. So we would 2. always have up to date atomic 
implementations, 3. allow the compiler to optimize code using atomicity and 4. 
thread sanatizers would start to work correctly and would not emit that huge 
amount of false alarms that we currently get with our asm atomic code.

CU
Christian