Rename type memory tag (TMT) to symbol memory tag (SMT)

[Diego Novillo]

Type memory tags (TMT) have been misnamed for a while now and will lose
even more meaning should the memory SSA scheme be useful.

One of the plans I have in mind is to allow passes to manually set the
alias set for a symbol in cases where they have much better context
information than what's available to the may alias pass.  This happens
today with passes like the vectorizer, where we create a pointer which
the vectorizer knows may only point to a specific array.  If we can
anchor the pointed-to set for the pointer symbol, then we don't suffer
the over-conservative decisions done by the alias pass.

On the other hand, the alias sets associated with TMTs are not purely
type-based, we try to use other properties to prune them, and we will
even try to ignore may-alias relations altogether at specific load/store
expressions.

Since these tags are associated with a pointer symbol, the name 'symbol
memory tag' (SMT) seems more appropriate.

The patch is longish but mind-numbingly mechanical.  Absolutely no
functional changes.

Bootstrap is still in progress, so I think I caught all the references
that matter for compilation.  I may have missed references to 'type tag'
or 'type memory tag' in comments and whatnot (hopefully I caught most
cases).

Will commit after bootstrap/testing finishes.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 20060301-rename-tmt-to-smt.diff
Type: text/x-patch
Size: 55686 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20060301/6a62d473/attachment.bin>