[r26468]

Create clean register requirements for Phis, otherwise reg_reqs_equal() and maybe others could get confused. It is unknown whether this caused any problems.

[r26467]

[r26465]

[r26464]

[r26461]

[r26460]

- improve block scheduling heuristic by deciding a priori which edge is the fall-through leaving a loop
- remove old extbb block scheduler

[r26459]

[r26458]

[r26453]

first occuring class (op(a,a) or op(a,b)), touch all and split the
touched list into halfs.
This should fix fehler170.c and is more logical and simpler code.

[r26446]

[r26444]

[r26440]

[r26438]

[r26437]

[r26429]

[r26427]

[r26424]

[r26423]

[r26422]

[r26421]

[r26420]

[r26419]

[r26416]

[r26415]

[r26414]

[r26413]

[r26412]

[r26411]

[r26410]

[r26409]

[r26408]

[r26407]

- Local rule to not propagate preferences on should_be_same for non-dying values
- Don't prefer phi-inputs for blocks which are not assigned yet

[r26406]

[r26405]

[r26404]

[r26402]

[r26401]

- fixed pass number

[r26397]

[r26396]

- add more passes

[r26395]