Why is D slower than LuaJIT?

[Walter Bright]

Andreas Mayer wrote:
> Or is D, unlike I thought, not suitable for high performance computing? What
> should I do?


I notice you are using doubles in D. dmd currently uses the x87 to evaluate 
doubles, and on some processors the x87 is slow relative to using the XMM 
instructions. Also, dmd's back end doesn't align the doubles on 16 byte 
boundaries, which can also slow down the floating point on some processors.

Both of these code gen issues with dmd are well known, and I'd like to solve 
them after we address higher priority issues.

If it's not clear, I'd like to emphasize that these are compiler issues, not D 
language issues.