llvm-svn: 152172

Affect on SD scheduling and postRA scheduling:
Printing the DAG will display the nodes in top-down topological order.
This matches the order within the MBB and makes my life much easier in general.

Affect on misched:
We don't need to track virtual register uses at all. This is awesome.
I also intend to rely on the SUnit ID as a topo-sort index. So if A < B then we cannot have an edge B -> A.

llvm-svn: 151135

llvm-svn: 150773

llvm-svn: 150552

Creates a configurable regalloc pipeline.

Ensure specific llc options do what they say and nothing more: -reglloc=... has no effect other than selecting the allocator pass itself. This patch introduces a new umbrella flag, "-optimize-regalloc", to enable/disable the optimizing regalloc "superpass". This allows for example testing coalscing and scheduling under -O0 or vice-versa.

When a CodeGen pass requires the MachineFunction to have a particular property, we need to explicitly define that property so it can be directly queried rather than naming a specific Pass. For example, to check for SSA, use MRI->isSSA, not addRequired<PHIElimination>.

CodeGen transformation passes are never "required" as an analysis

ProcessImplicitDefs does not require LiveVariables.

We have a plan to massively simplify some of the early passes within the regalloc superpass.

llvm-svn: 150226

llvm-svn: 150121

llvm-svn: 150043

llvm-svn: 150041

around within a basic block while maintaining live-intervals.

Updated ScheduleTopDownLive in MachineScheduler.cpp to use the moveInstr API
when reordering MIs.

llvm-svn: 149147

llvm-svn: 148291

Responding to code review.

llvm-svn: 148290

llvm-svn: 148174

llvm-svn: 148172

llvm-svn: 148171

llvm-svn: 148170

llvm-svn: 148105