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

[Pengcheng Wang via llvm-commits]

https://github.com/wangpc-pp created https://github.com/llvm/llvm-project/pull/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.


>From 26c95cae3937a421b5b9ac2af2fc0ad197bc6ed9 Mon Sep 17 00:00:00 2001
From: Wang Pengcheng <wangpengcheng.pp at bytedance.com>
Date: Thu, 24 Oct 2024 20:01:35 +0800
Subject: [PATCH] [CodeGen][MISched] Set DumpDirection after initPolicy

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.
---
 llvm/include/llvm/CodeGen/MachineScheduler.h |  7 ++++--
 llvm/lib/CodeGen/MachineScheduler.cpp        | 26 ++++++++------------
 2 files changed, 15 insertions(+), 18 deletions(-)

diff --git a/llvm/include/llvm/CodeGen/MachineScheduler.h b/llvm/include/llvm/CodeGen/MachineScheduler.h
index b15abf040058e8..f82f8f9ccf6647 100644
--- a/llvm/include/llvm/CodeGen/MachineScheduler.h
+++ b/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
@@ -1167,6 +1168,8 @@ class GenericSchedulerBase : public MachineSchedStrategy {
   const TargetSchedModel *SchedModel = nullptr;
   const TargetRegisterInfo *TRI = nullptr;
 
+  MachineSchedPolicy RegionPolicy;
+
   SchedRemainder Rem;
 
   GenericSchedulerBase(const MachineSchedContext *C) : Context(C) {}
@@ -1174,6 +1177,8 @@ class GenericSchedulerBase : public MachineSchedStrategy {
   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;
diff --git a/llvm/lib/CodeGen/MachineScheduler.cpp b/llvm/lib/CodeGen/MachineScheduler.cpp
index 9b2862de22b690..757f49293993e1 100644
--- a/llvm/lib/CodeGen/MachineScheduler.cpp
+++ b/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