GitLab

This requires to actually compute volatility in a number of places.
Therefore, this also adds some helper functions to do that.

The parallelization functions now keep track of all visited nodes, and do
not visit any node twice anymore. Hopefully, this finally makes
parallelize_mem polynomial in time.

If a Store uses the value and memory output of a Load just before it, and
shares the same pointer with the Load, the Store is killed.

The new code has less options and variants, if you call irg_verify()
verification is performed, regardless of DEBUG_libfirm, or NDEBUG being
set and regardless of firm verification setting switches. On the other
side no atomic dump and abort is performed anymore, the call has to do
this, though an irg_assert_verify() function has been added as a
convenience measure.
There has also been a complete rewrite of the actual checking performed.
The new code is simpler, should produce more consistent output and
can report more than one error.

also removed some assert(0) used in verifiers to stop when compiling
with assertions (you better use your debugger to stop and keep the code
clean)

- Previously it was part of load-store optimisations, the rewrite now
works as a localopt.
- The new version works for address arithmetic and not for Sels anymore
  (while the old code only worked for Sels)
- The new version can handle some forms of initializer spanning loads
  like loading a string like "bla" with an mode_Iu to get all 3 chars
  and the zero in one load.

also move copy_const_value from typerep/entity to irgmod.

This is necessary because the walker does not guarantee that all Projs
of the second Tuple are visited after we optimized the first Tuple.

No need to do it in backend preparation phase, if some backends destroy
the property again before transformation.

This also fixes a bug where irout computation would claim that it
removed all tuples, but missed tuples just held by a keepalive edge.

This fixes opt/ifconv5.c and 400.perlbench.

This fix is necessary to avoid an assert in the new
itfield/compound_member code.

We do not model them as a type anymore, but simply annotate
compound_member entities with a bit offset and bit size.