The opcode list was a member of irprog before which wasn't really
handled consistently. Also make sure opcodes are properly freed at
ir_finish().

unknown_type, code_type, none_type, unknown_entity reference are hold in
the irprog now. This makes handling more consistent since now all types
and entities are equally part of irprog.

Replace with equivalent pset_ptr stuff

It should only be used by construction algorithms

public functions are already documented in their headers, no need to
repeat the comment at the definition site.

They're pointless with the new switch representation introduced a while
ago.

memops are nodes that have memory inputs, you can generically query them
for their memory input. We can also get rid of get_fragile_op_mem in
favor of get_memop_mem.

Moves code from ifg dot-file dumpers around and produces .vcg graphs
now (ycomp layout is way better than xdot)

We just define that the only reason a Load/Store node can use the
exception edge is a NULL pointer. Misaligned Load/Store is a problem for
low-level languages which don't use exception edges anyway.

We simply always assume that Sel can only return a null pointer if
its input is a null pointer.

this is part of the initiative to move object-orientation support stuff
out of libfirm into liboo

build_edges_walker calls get_block_n on block preds, possibly consing
and hashing a node which init_lh_walker couldn't reach via
irg_walk_anchors.

This fixes a crash I see when compiling Postgres.

This should fix all known bugs, make the code easier to read and more
robust.

We already saved different entity attributes depending on the entity
type and an is_parameter flag. This unifies handling of different entity
types and introduces normal, method, parameter, label and
compound_member entities.

Make sure all types are in the global type list, remove type_walk_prog
which was a strange alternative to type_walk attempting to not miss
types not in the global list.