BugFix: test for parity on unordered compares

emit block labels for switchjmp targets

- Fix Projs returning wrong register requirements for in positions

- warning fixes

  as the irextbb algo fails for critical edges
- Make sure removed nodes have their preds set to Bad
- some cleanups

 - emitting fcom instructions completely broken
 - added support for floating point Perm

- Make ia32_Push and ia32_Pop return their stackpointer adjustment
- replaced stack_dir enum + unsigned offsets with normal integer offsets
- make schedule verifier detect dead nodes in schedule

- when turning adressmode nodes back to normal nodes, set base and index input
  to NoReg

removed be_AddSP emitter

- Extend spillslot verifier to detect "lonely" spills
- Make ia32 backend display warnings when emitting unknown nodes