#include "llvm/CodeGen/DFAPacketizer.h"
#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrBundle.h"
+#include "llvm/CodeGen/ScheduleDAGInstrs.h"
#include "llvm/MC/MCInstrItineraries.h"
+#include "llvm/Target/TargetInstrInfo.h"
using namespace llvm;
-DFAPacketizer::DFAPacketizer(const InstrItineraryData *I, const int (*SIT)[2],
- const unsigned* SET):
+// --------------------------------------------------------------------
+// Definitions shared between DFAPacketizer.cpp and DFAPacketizerEmitter.cpp
+
+namespace {
+ DFAInput addDFAFuncUnits(DFAInput Inp, unsigned FuncUnits) {
+ return (Inp << DFA_MAX_RESOURCES) | FuncUnits;
+ }
+
+ /// Return the DFAInput for an instruction class input vector.
+ /// This function is used in both DFAPacketizer.cpp and in
+ /// DFAPacketizerEmitter.cpp.
+ DFAInput getDFAInsnInput(const std::vector<unsigned> &InsnClass) {
+ DFAInput InsnInput = 0;
+ assert ((InsnClass.size() <= DFA_MAX_RESTERMS) &&
+ "Exceeded maximum number of DFA terms");
+ for (auto U : InsnClass)
+ InsnInput = addDFAFuncUnits(InsnInput, U);
+ return InsnInput;
+ }
+}
+// --------------------------------------------------------------------
+
+DFAPacketizer::DFAPacketizer(const InstrItineraryData *I,
+ const DFAStateInput (*SIT)[2],
+ const unsigned *SET):
InstrItins(I), CurrentState(0), DFAStateInputTable(SIT),
- DFAStateEntryTable(SET) {}
+ DFAStateEntryTable(SET) {
+ // Make sure DFA types are large enough for the number of terms & resources.
+ assert((DFA_MAX_RESTERMS * DFA_MAX_RESOURCES) <= (8 * sizeof(DFAInput))
+ && "(DFA_MAX_RESTERMS * DFA_MAX_RESOURCES) too big for DFAInput");
+ assert((DFA_MAX_RESTERMS * DFA_MAX_RESOURCES) <= (8 * sizeof(DFAStateInput))
+ && "(DFA_MAX_RESTERMS * DFA_MAX_RESOURCES) too big for DFAStateInput");
+}
//
-// ReadTable - Read the DFA transition table and update CachedTable
+// ReadTable - Read the DFA transition table and update CachedTable.
//
// Format of the transition tables:
// DFAStateInputTable[][2] = pairs of <Input, Transition> for all valid
unsigned ThisState = DFAStateEntryTable[state];
unsigned NextStateInTable = DFAStateEntryTable[state+1];
// Early exit in case CachedTable has already contains this
- // state's transitions
+ // state's transitions.
if (CachedTable.count(UnsignPair(state,
DFAStateInputTable[ThisState][0])))
return;
DFAStateInputTable[i][1];
}
+//
+// getInsnInput - Return the DFAInput for an instruction class.
+//
+DFAInput DFAPacketizer::getInsnInput(unsigned InsnClass) {
+ // Note: this logic must match that in DFAPacketizerDefs.h for input vectors.
+ DFAInput InsnInput = 0;
+ unsigned i = 0;
+ for (const InstrStage *IS = InstrItins->beginStage(InsnClass),
+ *IE = InstrItins->endStage(InsnClass); IS != IE; ++IS, ++i) {
+ InsnInput = addDFAFuncUnits(InsnInput, IS->getUnits());
+ assert ((i < DFA_MAX_RESTERMS) && "Exceeded maximum number of DFA inputs");
+ }
+ return InsnInput;
+}
+
+// getInsnInput - Return the DFAInput for an instruction class input vector.
+DFAInput DFAPacketizer::getInsnInput(const std::vector<unsigned> &InsnClass) {
+ return getDFAInsnInput(InsnClass);
+}
// canReserveResources - Check if the resources occupied by a MCInstrDesc
-// are available in the current state
-bool DFAPacketizer::canReserveResources(const llvm::MCInstrDesc* MID) {
+// are available in the current state.
+bool DFAPacketizer::canReserveResources(const llvm::MCInstrDesc *MID) {
unsigned InsnClass = MID->getSchedClass();
- const llvm::InstrStage* IS = InstrItins->beginStage(InsnClass);
- unsigned FuncUnits = IS->getUnits();
- UnsignPair StateTrans = UnsignPair(CurrentState, FuncUnits);
+ DFAInput InsnInput = getInsnInput(InsnClass);
+ UnsignPair StateTrans = UnsignPair(CurrentState, InsnInput);
ReadTable(CurrentState);
return (CachedTable.count(StateTrans) != 0);
}
-
// reserveResources - Reserve the resources occupied by a MCInstrDesc and
-// change the current state to reflect that change
-void DFAPacketizer::reserveResources(const llvm::MCInstrDesc* MID) {
+// change the current state to reflect that change.
+void DFAPacketizer::reserveResources(const llvm::MCInstrDesc *MID) {
unsigned InsnClass = MID->getSchedClass();
- const llvm::InstrStage* IS = InstrItins->beginStage(InsnClass);
- unsigned FuncUnits = IS->getUnits();
- UnsignPair StateTrans = UnsignPair(CurrentState, FuncUnits);
+ DFAInput InsnInput = getInsnInput(InsnClass);
+ UnsignPair StateTrans = UnsignPair(CurrentState, InsnInput);
ReadTable(CurrentState);
assert(CachedTable.count(StateTrans) != 0);
CurrentState = CachedTable[StateTrans];
// canReserveResources - Check if the resources occupied by a machine
-// instruction are available in the current state
-bool DFAPacketizer::canReserveResources(llvm::MachineInstr* MI) {
- const llvm::MCInstrDesc& MID = MI->getDesc();
+// instruction are available in the current state.
+bool DFAPacketizer::canReserveResources(llvm::MachineInstr *MI) {
+ const llvm::MCInstrDesc &MID = MI->getDesc();
return canReserveResources(&MID);
}
// reserveResources - Reserve the resources occupied by a machine
-// instruction and change the current state to reflect that change
-void DFAPacketizer::reserveResources(llvm::MachineInstr* MI) {
- const llvm::MCInstrDesc& MID = MI->getDesc();
+// instruction and change the current state to reflect that change.
+void DFAPacketizer::reserveResources(llvm::MachineInstr *MI) {
+ const llvm::MCInstrDesc &MID = MI->getDesc();
reserveResources(&MID);
}
+
+namespace llvm {
+// DefaultVLIWScheduler - This class extends ScheduleDAGInstrs and overrides
+// Schedule method to build the dependence graph.
+class DefaultVLIWScheduler : public ScheduleDAGInstrs {
+private:
+ AliasAnalysis *AA;
+public:
+ DefaultVLIWScheduler(MachineFunction &MF, MachineLoopInfo &MLI,
+ AliasAnalysis *AA);
+ // Schedule - Actual scheduling work.
+ void schedule() override;
+};
+}
+
+DefaultVLIWScheduler::DefaultVLIWScheduler(MachineFunction &MF,
+ MachineLoopInfo &MLI,
+ AliasAnalysis *AA)
+ : ScheduleDAGInstrs(MF, &MLI), AA(AA) {
+ CanHandleTerminators = true;
+}
+
+void DefaultVLIWScheduler::schedule() {
+ // Build the scheduling graph.
+ buildSchedGraph(AA);
+}
+
+// VLIWPacketizerList Ctor
+VLIWPacketizerList::VLIWPacketizerList(MachineFunction &MF,
+ MachineLoopInfo &MLI, AliasAnalysis *AA)
+ : MF(MF), AA(AA) {
+ TII = MF.getSubtarget().getInstrInfo();
+ ResourceTracker = TII->CreateTargetScheduleState(MF.getSubtarget());
+ VLIWScheduler = new DefaultVLIWScheduler(MF, MLI, AA);
+}
+
+// VLIWPacketizerList Dtor
+VLIWPacketizerList::~VLIWPacketizerList() {
+ if (VLIWScheduler)
+ delete VLIWScheduler;
+
+ if (ResourceTracker)
+ delete ResourceTracker;
+}
+
+// endPacket - End the current packet, bundle packet instructions and reset
+// DFA state.
+void VLIWPacketizerList::endPacket(MachineBasicBlock *MBB,
+ MachineInstr *MI) {
+ if (CurrentPacketMIs.size() > 1) {
+ MachineInstr *MIFirst = CurrentPacketMIs.front();
+ finalizeBundle(*MBB, MIFirst->getIterator(), MI->getIterator());
+ }
+ CurrentPacketMIs.clear();
+ ResourceTracker->clearResources();
+}
+
+// PacketizeMIs - Bundle machine instructions into packets.
+void VLIWPacketizerList::PacketizeMIs(MachineBasicBlock *MBB,
+ MachineBasicBlock::iterator BeginItr,
+ MachineBasicBlock::iterator EndItr) {
+ assert(VLIWScheduler && "VLIW Scheduler is not initialized!");
+ VLIWScheduler->startBlock(MBB);
+ VLIWScheduler->enterRegion(MBB, BeginItr, EndItr,
+ std::distance(BeginItr, EndItr));
+ VLIWScheduler->schedule();
+
+ // Generate MI -> SU map.
+ MIToSUnit.clear();
+ for (unsigned i = 0, e = VLIWScheduler->SUnits.size(); i != e; ++i) {
+ SUnit *SU = &VLIWScheduler->SUnits[i];
+ MIToSUnit[SU->getInstr()] = SU;
+ }
+
+ // The main packetizer loop.
+ for (; BeginItr != EndItr; ++BeginItr) {
+ MachineInstr *MI = BeginItr;
+
+ this->initPacketizerState();
+
+ // End the current packet if needed.
+ if (this->isSoloInstruction(MI)) {
+ endPacket(MBB, MI);
+ continue;
+ }
+
+ // Ignore pseudo instructions.
+ if (this->ignorePseudoInstruction(MI, MBB))
+ continue;
+
+ SUnit *SUI = MIToSUnit[MI];
+ assert(SUI && "Missing SUnit Info!");
+
+ // Ask DFA if machine resource is available for MI.
+ bool ResourceAvail = ResourceTracker->canReserveResources(MI);
+ if (ResourceAvail && shouldAddToPacket(MI)) {
+ // Dependency check for MI with instructions in CurrentPacketMIs.
+ for (std::vector<MachineInstr*>::iterator VI = CurrentPacketMIs.begin(),
+ VE = CurrentPacketMIs.end(); VI != VE; ++VI) {
+ MachineInstr *MJ = *VI;
+ SUnit *SUJ = MIToSUnit[MJ];
+ assert(SUJ && "Missing SUnit Info!");
+
+ // Is it legal to packetize SUI and SUJ together.
+ if (!this->isLegalToPacketizeTogether(SUI, SUJ)) {
+ // Allow packetization if dependency can be pruned.
+ if (!this->isLegalToPruneDependencies(SUI, SUJ)) {
+ // End the packet if dependency cannot be pruned.
+ endPacket(MBB, MI);
+ break;
+ } // !isLegalToPruneDependencies.
+ } // !isLegalToPacketizeTogether.
+ } // For all instructions in CurrentPacketMIs.
+ } else {
+ // End the packet if resource is not available, or if the instruction
+ // shoud not be added to the current packet.
+ endPacket(MBB, MI);
+ }
+
+ // Add MI to the current packet.
+ BeginItr = this->addToPacket(MI);
+ } // For all instructions in BB.
+
+ // End any packet left behind.
+ endPacket(MBB, EndItr);
+ VLIWScheduler->exitRegion();
+ VLIWScheduler->finishBlock();
+}