#endif
};
+/// Mutate the DAG as a postpass after normal DAG building.
+class ScheduleDAGMutation {
+public:
+ virtual ~ScheduleDAGMutation() {}
+
+ virtual void apply(ScheduleDAGMI *DAG) = 0;
+};
+
/// ScheduleDAGMI is an implementation of ScheduleDAGInstrs that schedules
/// machine instructions while updating LiveIntervals and tracking regpressure.
class ScheduleDAGMI : public ScheduleDAGInstrs {
RegisterClassInfo *RegClassInfo;
MachineSchedStrategy *SchedImpl;
+ /// Ordered list of DAG postprocessing steps.
+ std::vector<ScheduleDAGMutation*> Mutations;
+
MachineBasicBlock::iterator LiveRegionEnd;
/// Register pressure in this region computed by buildSchedGraph.
delete SchedImpl;
}
+ /// Add a postprocessing step to the DAG builder.
+ /// Mutations are applied in the order that they are added after normal DAG
+ /// building and before MachineSchedStrategy initialization.
+ void addMutation(ScheduleDAGMutation *Mutation) {
+ Mutations.push_back(Mutation);
+ }
+
MachineBasicBlock::iterator top() const { return CurrentTop; }
MachineBasicBlock::iterator bottom() const { return CurrentBottom; }
/// bottom of the DAG region without covereing any unscheduled instruction.
void buildDAGWithRegPressure();
+ /// Apply each ScheduleDAGMutation step in order. This allows different
+ /// instances of ScheduleDAGMI to perform custom DAG postprocessing.
+ void postprocessDAG();
+
/// Identify DAG roots and setup scheduler queues.
void initQueues();
void ScheduleDAGMI::schedule() {
buildDAGWithRegPressure();
+ postprocessDAG();
+
DEBUG(for (unsigned su = 0, e = SUnits.size(); su != e; ++su)
SUnits[su].dumpAll(this));
initRegPressure();
}
+/// Apply each ScheduleDAGMutation step in order.
+void ScheduleDAGMI::postprocessDAG() {
+ for (unsigned i = 0, e = Mutations.size(); i < e; ++i) {
+ Mutations[i]->apply(this);
+ }
+}
+
/// Identify DAG roots and setup scheduler queues.
void ScheduleDAGMI::initQueues() {
// Initialize the strategy before modifying the DAG.