SIMD support...

[a]

> Would this tie SIMD support directly to x86/x86_64, or would it
> possible to also support NEON on ARM (also 128 bit SIMD, see
> http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0409g/index.html
> ) ?
> (Obviously not for DMD, but if the syntax wasn't directly tied to
> x86/64, GDC and LDC could support this)
> It seems like using a standard naming convention instead of directly
> referencing instructions could let the underlying SIMD instructions
> vary across platforms, but I don't know enough about the technologies
> to say whether NEON's capabilities match SSE closely enough that they
> could be handled the same way.

For NEON you would need at least a function with a signature:

__v128 simdop(operator, __v128 op1, __v128 op2,  __v128 op3);

since many NEON instructions operate on three registers.