Make the list scheduler a set of helper functions, instead of a complex
design with a set of callbacks.
Simplified list scheduler code.

All users of NEW_ARR_A used it to construct a simple array, yet noone
cared about it actually being an array with a length field in front. For
this simple use case you should use ALLOCAN.

It has been empty for nearly all systems. People who used to put stuff
in config.h can still create a config.h on their own and inject
-include (gcc) or /FI (msvc) into their CPPFLAGS.

Just state the copyright and the project the files belong to. You can
then find the COPYING file for the whole project.

The test simply makes no sense.

This tries to get the names in a consistent format. We basically have 2
views on register allocation/constraints now:

1) Register Requirements and Assigments are per-instruction. Each
   instruction has requirements on its inputs and outputs, register get
   assigned for outputs of an instruction (assignment is an attribute of
   an instruction, not of the Proj-nodes).
   The internal datastructures model this form!

   The functions here have the form:
     arch_get_irn_register_req_in(node, input_nr)
     arch_get_irn_register_in(node, input_nr)
     arch_get_irn_register_req_out(node, output_nr)
     arch_set_irn_register_out(node, output_nr, register)

2) Register Requirements and Assignments are on firm-values. This view
   allows to query/assign requirements and registers at the Proj nodes
   instead of the repsective predecessors.
   This is a convenience interface modeled on top of the other!

   The functions have the form:
     arch_get_irn_register_req(node)
     arch_get_irn_register(node)
     arch_set_irn_register(node, register)

[r28127]

[r28010]

[r27970]

[r27693]

remove the (mis-)feature of arch_get_irn_reg_req_out working on mode_T nodes and retruning no_reqs in this case

[r27648]

[r27277]

[r26535]

[r26468]

  (We have a separate get_input, and get_output callback for now).
  This should make the code faster for now and is a first step towards
  changing the interface to query register constraints on the mode_T node
  itself instead of the Proj nodes.
- Handle middleend node constraints and stuff in benode.c instead of in each
  backend
- Remove irn_class_branch we already had is_cfop in the middleend
- Fix a bunch of bugs/problems in the process

[r26320]

[r26317]

  by a mostly O(1) access
- simpler memory freeing

[r23161]

[r23160]

- link resource is used until scheduler ends, honor that

[r23159]

[r23158]

[r23157]

- reserve the IRN_LINK resource

[r23156]