Updated Intel' s Manuals (DR AGNER FOG' s comments would be highly appreciated)

[Apl_and_Asm]

       
All Intel' s manuals (except the Optimization Manual) have been updated (September 2008).
Most notably the section dealing with "Memory ordering" in the System Programming manual
has been rewritten (rules, as stated, are more accurate) and enriched with several examples.
Intel remains fuzzy as to writes with WC semantics: it is said that when read/write acesses to
uncached memory occur, partially filled WC buffers are written to system memory.
This is an important point because WC semantics are used for non-temporal writes and we
should know when these writes of buffers' contents are triggered: Upon access to any
any uncached memory location, or only when uncached memory locations are those whose (future)
data is held by WC buffers ? In this case are writes limited to the one WC buffer holding the
data corresponding to the uncached memory location or are all WC buffers' contents written to
memory ? These points should be quite clear. Indeed we must know whether we can access
uncached memory locations which do not coincide with those corresponding to non-temporal
writes without hampering the non-temporal write process (by triggering early WC buffers writes
to memory). World-renowned specialist Dr Agner Fog' s comments would be highly appreciated.