Removing/deprecating -fvia-c

[Don Stewart]

igloo:
> 
> Hi all,
> 
> We are planning to remove the -fvia-c way of compiling code
> (unregisterised compilers will continue to compile via C only, but
> registerised compilers will only use the native code generator).
> We'll probably deprecate -fvia-c in the 6.14 branch, and remove it in
> 6.16.
> 
> Simon Marlow has recently fixed FP performance for modern x86 chips in
> the native code generator in the HEAD. That was the last reason we know
> of to prefer via-C to the native code generators. But before we start
> the removal process, does anyone know of any other problems with the
> native code generators that need to be fixed first?
> 

Do we have the blessing of the DPH team, wrt. tight, numeric inner loops?

As recently as last year -fvia-C -optc-O3 was still useful for some
microbenchmarks -- what's changed in that time, or is expected to change?

-- Don