mi-sched: Reorder Cyclicpath (latency) and CriticalMax (pressure) heuristics.

The latency based scheduling could induce spills in some cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190177 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/MachineScheduler.cpp b/lib/CodeGen/MachineScheduler.cpp
index b854a13f0aadcf01ca1fa5bb2868efa667e39362..7d957b5f3029b90dab0c62ff69a573ffe3805241 100644 (file)
--- a/lib/CodeGen/MachineScheduler.cpp
+++ b/lib/CodeGen/MachineScheduler.cpp
@@ -2469,16 +2469,16 @@ void ConvergingScheduler::tryCandidate(SchedCandidate &Cand,
                                                TryCand, Cand, RegExcess))
     return;
 
-  // For loops that are acyclic path limited, aggressively schedule for latency.
-  if (Rem.IsAcyclicLatencyLimited && tryLatency(TryCand, Cand, Zone))
-    return;
-
   // Avoid increasing the max critical pressure in the scheduled region.
   if (DAG->isTrackingPressure() && tryPressure(TryCand.RPDelta.CriticalMax,
                                                Cand.RPDelta.CriticalMax,
                                                TryCand, Cand, RegCritical))
     return;
 
+  // For loops that are acyclic path limited, aggressively schedule for latency.
+  if (Rem.IsAcyclicLatencyLimited && tryLatency(TryCand, Cand, Zone))
+    return;
+
   // Keep clustered nodes together to encourage downstream peephole
   // optimizations which may reduce resource requirements.
   //