[llvm-commits] [llvm] r92806 - /llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp

[Bill Wendling]

Author: void
Date: Tue Jan  5 17:48:12 2010
New Revision: 92806

URL: http://llvm.org/viewvc/llvm-project?rev=92806&view=rev
Log:
Add a semi-primitive form of scheduling via the "SDNode ordering" to the
bottom-up scheduler. We prefer the lower order number.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp?rev=92806&r1=92805&r2=92806&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp Tue Jan  5 17:48:12 2010
@@ -1038,6 +1038,10 @@
         return 0;
       return SethiUllmanNumbers[SU->NodeNum];
     }
+
+    unsigned getNodeOrdering(const SUnit *SU) const {
+      return scheduleDAG->DAG->GetOrdering(SU->getNode());
+    }
     
     unsigned size() const { return Queue.size(); }
 
@@ -1120,6 +1124,14 @@
 
 // Bottom up
 bool bu_ls_rr_sort::operator()(const SUnit *left, const SUnit *right) const {
+  unsigned LOrder = SPQ->getNodeOrdering(left);
+  unsigned ROrder = SPQ->getNodeOrdering(right);
+
+  // Prefer an ordering where the lower the non-zero order number, the higher
+  // the preference.
+  if ((LOrder || ROrder) && LOrder != ROrder)
+    return LOrder != 0 && (LOrder < ROrder || ROrder == 0);
+
   unsigned LPriority = SPQ->getNodePriority(left);
   unsigned RPriority = SPQ->getNodePriority(right);
   if (LPriority != RPriority)