[Mesa-dev] RFC: remove ctx->Driver.TextureMemCpy() hook

[Brian Paul]

This hook was added many years ago to allow using an alternative 
implementation of memcpy() for glTexImage() that was faster under some 
circumstances.

The code is still present in the state tracker in st_cb_texture.c

The hook is only used in texstore.c in the memcpy_texture() helper. 
It's not used for glCompressedTex[Sub]Image nor a few other places 
where it could have been used.

The non-gallium drivers just set ctx->Driver.TextureMemCpy = memcpy so 
it's really not utilized there.

If we think that using regular memcpy() everywhere is OK, I'd like to 
remove this hook.  I haven't done any investigation into whether the 
assembly __memcpy() function in st_cb_teximage.c is really any faster 
nowadays.  But if there really is a benefit to this function, we could 
use it in more places.

Any comments?

-Brian