This makes it consistent with other firm analyse functions. Also removes
the unnecessary return value.

graph_properties are things that a transformation may destroy but which
can be easily recalculated.

graph_constraints are set after lowering phases have been running and
forbid certain constructs that no (later) transformation is allowed to construct

First it is unclear what is a good way to deconstruct a program into extended
basic blocks, also none of our optimizations works on extended basic
blocks.

It was a member of ir_prog before but not correctly handled.

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().

This is the new way of handling switch-jumps. The node contains a table
which maps (ranges of) input values to proj numbers. Compared to a
Cond-node this results in a clean consecutive sequence of Proj numbers
(no searching for a free number for the default_pn anymore) and allows
factoring multiple cases jumping to the same block in a single Proj
(though we still need the optimisation in cfopt for that).

The main change here is splitting new_ir_mode into new_int_mode,
new_reference_mode and new_float_mode. You can now specify
mantissa+exponent size in new_float_mode. This also changes:

- x86 80bit-FP mode is NOT a ieee754 don't put "ieee754" into functions
  names that can also handle x86 80bit fps
- Move ieee_descriptor_t from tarval module into ir_mode struct
  (and rename to float_descriptor_t)
- Introduce mode_Q which represents binary128 from ieee754
- You can ask float modes for mantissa/exponent sizes now
- Fix endianess when emitting big float values in begnuas
- A bunch of long double fixes in ia32: the mode there has 10bytes
  (80bit) but the variables typically are 12 or 16 byte big
- This fixes some problems of sparc binary128 handling

Use a special kind of entity on the frame type instead of a value_type
struct inside a method type. This makes replacement of function types
slightly easier (it's still a complex operation though) and handling in
the backend a bit more consistent since it's more or less a normal stack
access (with special offsets).

There might be some ProjL nodes reachable via out edges
and the following "local" phase does enqueue_users for
optimized nodes, which might visit the 'undead' ProjL.

We can still use ia32 ShlD, ShrD functions by matching Or(Shl,Shr)
patterns in the ia32 transformer.