[llvm] Reland "CodeGen][NewPM] Port MachineScheduler to NPM. (#125703)" (PR #126684)

[Akshat Oke via llvm-commits]

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@@ -385,39 +436,100 @@ nextIfDebug(MachineBasicBlock::iterator I,
 }
 
 /// Instantiate a ScheduleDAGInstrs that will be owned by the caller.
-ScheduleDAGInstrs *MachineScheduler::createMachineScheduler() {
+ScheduleDAGInstrs *MachineSchedulerImpl::createMachineScheduler() {
   // Select the scheduler, or set the default.
   MachineSchedRegistry::ScheduleDAGCtor Ctor = MachineSchedOpt;
   if (Ctor != useDefaultMachineSched)
     return Ctor(this);
 
-  const TargetMachine &TM =
-      getAnalysis<TargetPassConfig>().getTM<TargetMachine>();
-
   // Get the default scheduler set by the target for this function.
-  ScheduleDAGInstrs *Scheduler = TM.createMachineScheduler(this);
+  ScheduleDAGInstrs *Scheduler = TM->createMachineScheduler(this);
   if (Scheduler)
     return Scheduler;
 
   // Default to GenericScheduler.
   return createGenericSchedLive(this);
 }
 
+bool MachineSchedulerImpl::run(MachineFunction &Func, const TargetMachine &TM,
+                               const RequiredAnalyses &Analyses) {
+  MF = &Func;
+  MLI = &Analyses.MLI;
+  MDT = &Analyses.MDT;
+  this->TM = &TM;
+  AA = &Analyses.AA;
+  LIS = &Analyses.LIS;
+
+  if (VerifyScheduling) {
+    LLVM_DEBUG(LIS->dump());
+    const char *MSchedBanner = "Before machine scheduling.";
+    if (P)
+      MF->verify(P, MSchedBanner, &errs());
+    else
+      MF->verify(*MFAM, MSchedBanner, &errs());
+  }
+  RegClassInfo->runOnMachineFunction(*MF);
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optimisan wrote:

There is a patch to convert it into an analysis: https://github.com/llvm/llvm-project/pull/120690

https://github.com/llvm/llvm-project/pull/126684