Reusing the same dummy struct as a hidden parameter for multiple
calls is not always correct (see opt/structcall2.c for an example).
For now, just use multiple dummy structs.

We can't handle 128bit long double in softfloat yet, but most libraries
are compiled like this. It's better to have the compiler fail than to
produce code with a mismatching ABI in the default setting.

Conflicts:
	ir/be/beverify.c

This reverts commit 2a018b81.

Unreachable loops always have a loop entry edge and thus a Phi node.

Both mature and immature blocks were dumped in ird_color_block_background.

In particular this allows ifconv when a PhiM is present, but nothing happens with the memory on the two paths.

This is a workaround for keepalive edges which are probably broken
(adding the stuff to the End node is wrong, it should get added to the
 endless loop somehow)

SymConst_addr_ent are never zero for example, also there's no need to
give up after seeing a confirm

I aligning them to a multiple of 100 now, so that when code generated in
an earlier functions only changes lightly it is very likely that the
block numbers in later functions stay the same.

Performing it as localopt was hairy as the optimisation dependet on
correct iredges values which were misleading/wrong during construction
of new stuff.

The middleend should optimize all these cases, it does so for 99% of
them already. There are just some cases where ands get transformed into
conversions which the middleend doesn't catch yet.

This needed some rewriting as ia32 previously checked already
transformed nodes while sparc was checking nodes before transformation.
Change ia32 to check nodes before transformation too. Also improved some
code in sparc+ia32.

The hashmap used to point to blocks which have already been deleted.