Experimental post-pass scheduling support. Post-pass scheduling

is currently off by default, and can be enabled with
-disable-post-RA-scheduler=false.

This doesn't have a significant impact on most code yet because it doesn't
yet do anything to address anti-dependencies and it doesn't attempt to
disambiguate memory references. Also, several popular targets
don't have pipeline descriptions yet.

The majority of the changes here are splitting the SelectionDAG-specific
code out of ScheduleDAG, so that ScheduleDAG can be moved to
libLLVMCodeGen.a. The interface between ScheduleDAG-using code and
the rest of the scheduling code is somewhat rough and will evolve.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59676 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CMakeLists.txt

@@ -8,6 +8,7 @@ add_llvm_library(LLVMCodeGen
   IfConversion.cpp
   IntrinsicLowering.cpp
   LLVMTargetMachine.cpp
+  LatencyPriorityQueue.cpp
   LiveInterval.cpp
   LiveIntervalAnalysis.cpp
   LiveStackAnalysis.cpp
@@ -40,6 +41,10 @@ add_llvm_library(LLVMCodeGen
   RegAllocSimple.cpp
   RegisterCoalescer.cpp
   RegisterScavenging.cpp
+  ScheduleDAG.cpp
+  ScheduleDAGEmit.cpp
+  ScheduleDAGInstrs.cpp
+  ScheduleDAGPrinter.cpp
   ShadowStackGC.cpp
   SimpleRegisterCoalescing.cpp
   StackProtector.cpp