[CodeGen][MISched] Set DumpDirection after initPolicy (#115112)

Previously we set the dump direction according to command line
options, but we may override the scheduling direction in `initPolicy`
and this results in mismatch between dump and actual policy.

Here we simply set the dump direction after initializing the policy.

Author: wangpc-pp

llvm/include/llvm/CodeGen/MachineScheduler.h

@@ -219,6 +219,7 @@ class MachineSchedStrategy {
                           MachineBasicBlock::iterator End,
                           unsigned NumRegionInstrs) {}
 
+  virtual MachineSchedPolicy getPolicy() const { return {}; }
   virtual void dumpPolicy() const {}
 
   /// Check if pressure tracking is needed before building the DAG and
@@ -1167,13 +1168,17 @@ class GenericSchedulerBase : public MachineSchedStrategy {
   const TargetSchedModel *SchedModel = nullptr;
   const TargetRegisterInfo *TRI = nullptr;
 
+  MachineSchedPolicy RegionPolicy;
+
   SchedRemainder Rem;
 
   GenericSchedulerBase(const MachineSchedContext *C) : Context(C) {}
 
   void setPolicy(CandPolicy &Policy, bool IsPostRA, SchedBoundary &CurrZone,
                  SchedBoundary *OtherZone);
 
+  MachineSchedPolicy getPolicy() const override { return RegionPolicy; }
+
 #ifndef NDEBUG
   void traceCandidate(const SchedCandidate &Cand);
 #endif
@@ -1254,8 +1259,6 @@ class GenericScheduler : public GenericSchedulerBase {
 protected:
   ScheduleDAGMILive *DAG = nullptr;
 
-  MachineSchedPolicy RegionPolicy;
-
   // State of the top and bottom scheduled instruction boundaries.
   SchedBoundary Top;
   SchedBoundary Bot;
@@ -1294,7 +1297,6 @@ class PostGenericScheduler : public GenericSchedulerBase {
   ScheduleDAGMI *DAG = nullptr;
   SchedBoundary Top;
   SchedBoundary Bot;
-  MachineSchedPolicy RegionPolicy;
 
   /// Candidate last picked from Top boundary.
   SchedCandidate TopCand;

llvm/lib/CodeGen/MachineScheduler.cpp

@@ -460,14 +460,6 @@ bool MachineScheduler::runOnMachineFunction(MachineFunction &mf) {
   // Instantiate the selected scheduler for this target, function, and
   // optimization level.
   std::unique_ptr<ScheduleDAGInstrs> Scheduler(createMachineScheduler());
-  ScheduleDAGMI::DumpDirection D;
-  if (ForceTopDown)
-    D = ScheduleDAGMI::DumpDirection::TopDown;
-  else if (ForceBottomUp)
-    D = ScheduleDAGMI::DumpDirection::BottomUp;
-  else
-    D = ScheduleDAGMI::DumpDirection::Bidirectional;
-  Scheduler->setDumpDirection(D);
   scheduleRegions(*Scheduler, false);
 
   LLVM_DEBUG(LIS->dump());
@@ -501,14 +493,6 @@ bool PostMachineScheduler::runOnMachineFunction(MachineFunction &mf) {
   // Instantiate the selected scheduler for this target, function, and
   // optimization level.
   std::unique_ptr<ScheduleDAGInstrs> Scheduler(createPostMachineScheduler());
-  ScheduleDAGMI::DumpDirection D;
-  if (PostRADirection == MISchedPostRASched::TopDown)
-    D = ScheduleDAGMI::DumpDirection::TopDown;
-  else if (PostRADirection == MISchedPostRASched::BottomUp)
-    D = ScheduleDAGMI::DumpDirection::BottomUp;
-  else
-    D = ScheduleDAGMI::DumpDirection::Bidirectional;
-  Scheduler->setDumpDirection(D);
   scheduleRegions(*Scheduler, true);
 
   if (VerifyScheduling)
@@ -796,6 +780,16 @@ void ScheduleDAGMI::enterRegion(MachineBasicBlock *bb,
   ScheduleDAGInstrs::enterRegion(bb, begin, end, regioninstrs);
 
   SchedImpl->initPolicy(begin, end, regioninstrs);
+
+  // Set dump direction after initializing sched policy.
+  ScheduleDAGMI::DumpDirection D;
+  if (SchedImpl->getPolicy().OnlyTopDown)
+    D = ScheduleDAGMI::DumpDirection::TopDown;
+  else if (SchedImpl->getPolicy().OnlyBottomUp)
+    D = ScheduleDAGMI::DumpDirection::BottomUp;
+  else
+    D = ScheduleDAGMI::DumpDirection::Bidirectional;
+  setDumpDirection(D);
 }
 
 /// This is normally called from the main scheduler loop but may also be invoked