The added unittest was failing and also x10i. Frontend moves global
entity into class for native method calls. liboo lowering moves it back
during vtable creation.

The issue is that "pmap_insert(map,key,NULL)" does not delete an entry,
so "pmap_contains(map,key)" afterwards does not return false. This
changes add_compound_member to assert a NULL value instead of a NULL
entry.

A similar error might be in ir/be/bechordal.c.

If the cached nodes like NoReg_GP, ... had no keep edge and no users
then irgwalks could miss them leading for the iredges code to miss
initializing these nodes.

This fixes bug 161.

This should fix the doxygen warning.

This is done by introducing a new new_global_entity() function for
constructing globals/adding a visibility argument to new_alias_entity().

The map maps global symbols to the respective entities in the segment
types. This should avoid hacks in some frontends, avoids a sepcial map
for compilerlib entities and ensures that frontend and compilerlib
entities are in sync.

This is cleaner than having them being class types with a tf_segment
flag set.

This reverts commit 19cccd2b.

The situation can actually occur:
The spiller might reload an operand of a CopyKeep right before the CopyKeep.
This defeats the entire purpose of the CopyKeep, so the no-spill Copy right before the CopyKept node is necessary.

Newer Linux systems compile ar with --enable-deterministic-archives,
which conflicts with the u modifier.

Now only e.g. 'setmask' works, but 'SetMAsK' does not anymore.
I think, the loss is acceptable.

This is handled earlier and there are no memory clobbers anymore in gen_ASM().

In particular remove the unnecessary 'sparc_is_valid_clobber()'.
The wrapper 'be_is_valid_clobber()' already handles 'memory' and 'cc'.

The algorithm now also works for Calls with exception Projs.

The simple tp_opcode enum is enough, no need to have dispatch tables and
information structs behind each type kind.

There is no need for dispatch through tpop, they all use the same
underlying data structure anyway, so just work on that in
get_compound_xxx()