On Wednesday, 9 September 2015 at 14:00:07 UTC, qznc wrote:
That is a good idea, if you want to measure compiler
optimizations. Ideally g++ and gdc should always yield the same
performance then?
Hopefully, as I understand GCC uses a highlevel IR, but if
performance is equal that is a pretty strong argument to get
people to adopt, if the rest of the language is polished.
And you could measure regressions.
Suppose you consider using D with C/C++ as the stable
alternative. D lures you with its high level features. However,
you know that you will have to really optimize some hot spots
sooner or later. Will D impose a penalty on you and C/C++ could
have provided better performance?
Walter argues that there is no technical reason why D should be
slower than C/C++. My experience with the benchmarks says,
there seem to be such penalties. For example, there is no
__builtin_ia32_cmplepd or __builtin_ia32_movmskpd like gcc has.
Ok, I see your point. You want to measure maximum throughput for
critical applications that might benefit from language specific
intrinsics.
Multithreaded applications could probably show some differences
too, due to TLS/shared...
Maybe some kind of actor based benchmark. Essentially running
thousands of fibers with lots of intercommunication.
