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			677 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			677 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===------- HexagonCopyToCombine.cpp - Hexagon Copy-To-Combine Pass ------===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| // This pass replaces transfer instructions by combine instructions.
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| // We walk along a basic block and look for two combinable instructions and try
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| // to move them together. If we can move them next to each other we do so and
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| // replace them with a combine instruction.
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| //===----------------------------------------------------------------------===//
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| #include "llvm/PassSupport.h"
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| #include "Hexagon.h"
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| #include "HexagonInstrInfo.h"
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| #include "HexagonMachineFunctionInfo.h"
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| #include "HexagonRegisterInfo.h"
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| #include "HexagonSubtarget.h"
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| #include "HexagonTargetMachine.h"
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| #include "llvm/ADT/DenseMap.h"
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| #include "llvm/ADT/DenseSet.h"
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| #include "llvm/CodeGen/MachineBasicBlock.h"
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| #include "llvm/CodeGen/MachineFunction.h"
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| #include "llvm/CodeGen/MachineFunctionPass.h"
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| #include "llvm/CodeGen/MachineInstr.h"
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| #include "llvm/CodeGen/MachineInstrBuilder.h"
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| #include "llvm/CodeGen/Passes.h"
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| #include "llvm/Support/CodeGen.h"
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| #include "llvm/Support/CommandLine.h"
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| #include "llvm/Support/Debug.h"
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| #include "llvm/Support/raw_ostream.h"
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| #include "llvm/Target/TargetRegisterInfo.h"
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| 
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| using namespace llvm;
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| 
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| #define DEBUG_TYPE "hexagon-copy-combine"
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| 
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| static
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| cl::opt<bool> IsCombinesDisabled("disable-merge-into-combines",
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|                                  cl::Hidden, cl::ZeroOrMore,
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|                                  cl::init(false),
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|                                  cl::desc("Disable merging into combines"));
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| static
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| cl::opt<unsigned>
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| MaxNumOfInstsBetweenNewValueStoreAndTFR("max-num-inst-between-tfr-and-nv-store",
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|                    cl::Hidden, cl::init(4),
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|                    cl::desc("Maximum distance between a tfr feeding a store we "
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|                             "consider the store still to be newifiable"));
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| 
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| namespace llvm {
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|   void initializeHexagonCopyToCombinePass(PassRegistry&);
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| }
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| 
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| 
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| namespace {
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| 
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| class HexagonCopyToCombine : public MachineFunctionPass  {
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|   const HexagonInstrInfo *TII;
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|   const TargetRegisterInfo *TRI;
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|   bool ShouldCombineAggressively;
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| 
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|   DenseSet<MachineInstr *> PotentiallyNewifiableTFR;
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| public:
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|   static char ID;
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| 
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|   HexagonCopyToCombine() : MachineFunctionPass(ID) {
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|     initializeHexagonCopyToCombinePass(*PassRegistry::getPassRegistry());
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|   }
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| 
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|   void getAnalysisUsage(AnalysisUsage &AU) const override {
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|     MachineFunctionPass::getAnalysisUsage(AU);
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|   }
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| 
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|   const char *getPassName() const override {
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|     return "Hexagon Copy-To-Combine Pass";
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|   }
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| 
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|   bool runOnMachineFunction(MachineFunction &Fn) override;
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| 
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| private:
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|   MachineInstr *findPairable(MachineInstr *I1, bool &DoInsertAtI1);
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| 
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|   void findPotentialNewifiableTFRs(MachineBasicBlock &);
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| 
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|   void combine(MachineInstr *I1, MachineInstr *I2,
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|                MachineBasicBlock::iterator &MI, bool DoInsertAtI1);
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| 
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|   bool isSafeToMoveTogether(MachineInstr *I1, MachineInstr *I2,
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|                             unsigned I1DestReg, unsigned I2DestReg,
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|                             bool &DoInsertAtI1);
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| 
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|   void emitCombineRR(MachineBasicBlock::iterator &Before, unsigned DestReg,
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|                      MachineOperand &HiOperand, MachineOperand &LoOperand);
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| 
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|   void emitCombineRI(MachineBasicBlock::iterator &Before, unsigned DestReg,
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|                      MachineOperand &HiOperand, MachineOperand &LoOperand);
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| 
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|   void emitCombineIR(MachineBasicBlock::iterator &Before, unsigned DestReg,
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|                      MachineOperand &HiOperand, MachineOperand &LoOperand);
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| 
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|   void emitCombineII(MachineBasicBlock::iterator &Before, unsigned DestReg,
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|                      MachineOperand &HiOperand, MachineOperand &LoOperand);
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| };
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| 
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| } // End anonymous namespace.
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| 
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| char HexagonCopyToCombine::ID = 0;
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| 
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| INITIALIZE_PASS(HexagonCopyToCombine, "hexagon-copy-combine",
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|                 "Hexagon Copy-To-Combine Pass", false, false)
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| 
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| static bool isCombinableInstType(MachineInstr *MI,
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|                                  const HexagonInstrInfo *TII,
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|                                  bool ShouldCombineAggressively) {
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|   switch(MI->getOpcode()) {
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|   case Hexagon::TFR: {
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|     // A COPY instruction can be combined if its arguments are IntRegs (32bit).
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|     assert(MI->getOperand(0).isReg() && MI->getOperand(1).isReg());
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| 
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|     unsigned DestReg = MI->getOperand(0).getReg();
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|     unsigned SrcReg = MI->getOperand(1).getReg();
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|     return Hexagon::IntRegsRegClass.contains(DestReg) &&
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|       Hexagon::IntRegsRegClass.contains(SrcReg);
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|   }
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| 
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|   case Hexagon::TFRI: {
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|     // A transfer-immediate can be combined if its argument is a signed 8bit
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|     // value.
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|     assert(MI->getOperand(0).isReg() && MI->getOperand(1).isImm());
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|     unsigned DestReg = MI->getOperand(0).getReg();
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| 
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|     // Only combine constant extended TFRI if we are in aggressive mode.
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|     return Hexagon::IntRegsRegClass.contains(DestReg) &&
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|       (ShouldCombineAggressively || isInt<8>(MI->getOperand(1).getImm()));
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|   }
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| 
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|   case Hexagon::TFRI_V4: {
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|     if (!ShouldCombineAggressively)
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|       return false;
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|     assert(MI->getOperand(0).isReg() && MI->getOperand(1).isGlobal());
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| 
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|     // Ensure that TargetFlags are MO_NO_FLAG for a global. This is a
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|     // workaround for an ABI bug that prevents GOT relocations on combine
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|     // instructions
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|     if (MI->getOperand(1).getTargetFlags() != HexagonII::MO_NO_FLAG)
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|       return false;
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| 
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|     unsigned DestReg = MI->getOperand(0).getReg();
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|     return Hexagon::IntRegsRegClass.contains(DestReg);
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|   }
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| 
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|   default:
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|     break;
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|   }
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| 
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|   return false;
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| }
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| 
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| static bool isGreaterThan8BitTFRI(MachineInstr *I) {
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|   return I->getOpcode() == Hexagon::TFRI &&
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|     !isInt<8>(I->getOperand(1).getImm());
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| }
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| static bool isGreaterThan6BitTFRI(MachineInstr *I) {
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|   return I->getOpcode() == Hexagon::TFRI &&
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|     !isUInt<6>(I->getOperand(1).getImm());
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| }
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| 
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| /// areCombinableOperations - Returns true if the two instruction can be merge
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| /// into a combine (ignoring register constraints).
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| static bool areCombinableOperations(const TargetRegisterInfo *TRI,
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|                                     MachineInstr *HighRegInst,
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|                                     MachineInstr *LowRegInst) {
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|   assert((HighRegInst->getOpcode() == Hexagon::TFR ||
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|           HighRegInst->getOpcode() == Hexagon::TFRI ||
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|           HighRegInst->getOpcode() == Hexagon::TFRI_V4) &&
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|          (LowRegInst->getOpcode() == Hexagon::TFR ||
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|           LowRegInst->getOpcode() == Hexagon::TFRI ||
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|           LowRegInst->getOpcode() == Hexagon::TFRI_V4) &&
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|          "Assume individual instructions are of a combinable type");
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| 
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|   const HexagonRegisterInfo *QRI =
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|     static_cast<const HexagonRegisterInfo *>(TRI);
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| 
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|   // V4 added some combine variations (mixed immediate and register source
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|   // operands), if we are on < V4 we can only combine 2 register-to-register
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|   // moves and 2 immediate-to-register moves. We also don't have
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|   // constant-extenders.
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|   if (!QRI->Subtarget.hasV4TOps())
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|     return HighRegInst->getOpcode() == LowRegInst->getOpcode() &&
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|       !isGreaterThan8BitTFRI(HighRegInst) &&
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|       !isGreaterThan6BitTFRI(LowRegInst);
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| 
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|   // There is no combine of two constant extended values.
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|   if ((HighRegInst->getOpcode() == Hexagon::TFRI_V4 ||
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|        isGreaterThan8BitTFRI(HighRegInst)) &&
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|       (LowRegInst->getOpcode() == Hexagon::TFRI_V4 ||
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|        isGreaterThan6BitTFRI(LowRegInst)))
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|     return false;
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| 
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|   return true;
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| }
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| 
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| static bool isEvenReg(unsigned Reg) {
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|   assert(TargetRegisterInfo::isPhysicalRegister(Reg) &&
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|          Hexagon::IntRegsRegClass.contains(Reg));
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|   return (Reg - Hexagon::R0) % 2 == 0;
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| }
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| 
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| static void removeKillInfo(MachineInstr *MI, unsigned RegNotKilled) {
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|   for (unsigned I = 0, E = MI->getNumOperands(); I != E; ++I) {
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|     MachineOperand &Op = MI->getOperand(I);
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|     if (!Op.isReg() || Op.getReg() != RegNotKilled || !Op.isKill())
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|       continue;
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|     Op.setIsKill(false);
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|   }
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| }
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| 
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| /// isUnsafeToMoveAcross - Returns true if it is unsafe to move a copy
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| /// instruction from \p UseReg to \p DestReg over the instruction \p I.
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| static bool isUnsafeToMoveAcross(MachineInstr *I, unsigned UseReg,
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|                                   unsigned DestReg,
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|                                   const TargetRegisterInfo *TRI) {
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|   return (UseReg && (I->modifiesRegister(UseReg, TRI))) ||
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|           I->modifiesRegister(DestReg, TRI) ||
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|           I->readsRegister(DestReg, TRI) ||
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|           I->hasUnmodeledSideEffects() ||
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|           I->isInlineAsm() || I->isDebugValue();
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| }
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| 
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| /// isSafeToMoveTogether - Returns true if it is safe to move I1 next to I2 such
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| /// that the two instructions can be paired in a combine.
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| bool HexagonCopyToCombine::isSafeToMoveTogether(MachineInstr *I1,
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|                                                 MachineInstr *I2,
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|                                                 unsigned I1DestReg,
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|                                                 unsigned I2DestReg,
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|                                                 bool &DoInsertAtI1) {
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| 
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|   bool IsImmUseReg = I2->getOperand(1).isImm() || I2->getOperand(1).isGlobal();
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|   unsigned I2UseReg = IsImmUseReg ? 0 : I2->getOperand(1).getReg();
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| 
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|   // It is not safe to move I1 and I2 into one combine if I2 has a true
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|   // dependence on I1.
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|   if (I2UseReg && I1->modifiesRegister(I2UseReg, TRI))
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|     return false;
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| 
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|   bool isSafe = true;
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| 
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|   // First try to move I2 towards I1.
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|   {
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|     // A reverse_iterator instantiated like below starts before I2, and I1
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|     // respectively.
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|     // Look at instructions I in between I2 and (excluding) I1.
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|     MachineBasicBlock::reverse_iterator I(I2),
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|       End = --(MachineBasicBlock::reverse_iterator(I1));
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|     // At 03 we got better results (dhrystone!) by being more conservative.
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|     if (!ShouldCombineAggressively)
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|       End = MachineBasicBlock::reverse_iterator(I1);
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|     // If I2 kills its operand and we move I2 over an instruction that also
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|     // uses I2's use reg we need to modify that (first) instruction to now kill
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|     // this reg.
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|     unsigned KilledOperand = 0;
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|     if (I2->killsRegister(I2UseReg))
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|       KilledOperand = I2UseReg;
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|     MachineInstr *KillingInstr = nullptr;
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| 
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|     for (; I != End; ++I) {
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|       // If the intervening instruction I:
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|       //   * modifies I2's use reg
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|       //   * modifies I2's def reg
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|       //   * reads I2's def reg
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|       //   * or has unmodelled side effects
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|       // we can't move I2 across it.
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|       if (isUnsafeToMoveAcross(&*I, I2UseReg, I2DestReg, TRI)) {
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|         isSafe = false;
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|         break;
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|       }
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| 
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|       // Update first use of the killed operand.
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|       if (!KillingInstr && KilledOperand &&
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|           I->readsRegister(KilledOperand, TRI))
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|         KillingInstr = &*I;
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|     }
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|     if (isSafe) {
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|       // Update the intermediate instruction to with the kill flag.
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|       if (KillingInstr) {
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|         bool Added = KillingInstr->addRegisterKilled(KilledOperand, TRI, true);
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|         (void)Added; // suppress compiler warning
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|         assert(Added && "Must successfully update kill flag");
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|         removeKillInfo(I2, KilledOperand);
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|       }
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|       DoInsertAtI1 = true;
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|       return true;
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|     }
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|   }
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| 
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|   // Try to move I1 towards I2.
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|   {
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|     // Look at instructions I in between I1 and (excluding) I2.
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|     MachineBasicBlock::iterator I(I1), End(I2);
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|     // At O3 we got better results (dhrystone) by being more conservative here.
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|     if (!ShouldCombineAggressively)
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|       End = std::next(MachineBasicBlock::iterator(I2));
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|     IsImmUseReg = I1->getOperand(1).isImm() || I1->getOperand(1).isGlobal();
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|     unsigned I1UseReg = IsImmUseReg ? 0 : I1->getOperand(1).getReg();
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|     // Track killed operands. If we move across an instruction that kills our
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|     // operand, we need to update the kill information on the moved I1. It kills
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|     // the operand now.
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|     MachineInstr *KillingInstr = nullptr;
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|     unsigned KilledOperand = 0;
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| 
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|     while(++I != End) {
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|       // If the intervening instruction I:
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|       //   * modifies I1's use reg
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|       //   * modifies I1's def reg
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|       //   * reads I1's def reg
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|       //   * or has unmodelled side effects
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|       //   We introduce this special case because llvm has no api to remove a
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|       //   kill flag for a register (a removeRegisterKilled() analogous to
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|       //   addRegisterKilled) that handles aliased register correctly.
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|       //   * or has a killed aliased register use of I1's use reg
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|       //           %D4<def> = TFRI64 16
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|       //           %R6<def> = TFR %R9
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|       //           %R8<def> = KILL %R8, %D4<imp-use,kill>
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|       //      If we want to move R6 = across the KILL instruction we would have
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|       //      to remove the %D4<imp-use,kill> operand. For now, we are
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|       //      conservative and disallow the move.
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|       // we can't move I1 across it.
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|       if (isUnsafeToMoveAcross(I, I1UseReg, I1DestReg, TRI) ||
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|           // Check for an aliased register kill. Bail out if we see one.
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|           (!I->killsRegister(I1UseReg) && I->killsRegister(I1UseReg, TRI)))
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|         return false;
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| 
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|       // Check for an exact kill (registers match).
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|       if (I1UseReg && I->killsRegister(I1UseReg)) {
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|         assert(!KillingInstr && "Should only see one killing instruction");
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|         KilledOperand = I1UseReg;
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|         KillingInstr = &*I;
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|       }
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|     }
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|     if (KillingInstr) {
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|       removeKillInfo(KillingInstr, KilledOperand);
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|       // Update I1 to set the kill flag. This flag will later be picked up by
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|       // the new COMBINE instruction.
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|       bool Added = I1->addRegisterKilled(KilledOperand, TRI);
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|       (void)Added; // suppress compiler warning
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|       assert(Added && "Must successfully update kill flag");
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|     }
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|     DoInsertAtI1 = false;
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|   }
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| 
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|   return true;
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| }
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| 
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| /// findPotentialNewifiableTFRs - Finds tranfers that feed stores that could be
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| /// newified. (A use of a 64 bit register define can not be newified)
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| void
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| HexagonCopyToCombine::findPotentialNewifiableTFRs(MachineBasicBlock &BB) {
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|   DenseMap<unsigned, MachineInstr *> LastDef;
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|   for (MachineBasicBlock::iterator I = BB.begin(), E = BB.end(); I != E; ++I) {
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|     MachineInstr *MI = I;
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|     // Mark TFRs that feed a potential new value store as such.
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|     if(TII->mayBeNewStore(MI)) {
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|       // Look for uses of TFR instructions.
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|       for (unsigned OpdIdx = 0, OpdE = MI->getNumOperands(); OpdIdx != OpdE;
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|            ++OpdIdx) {
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|         MachineOperand &Op = MI->getOperand(OpdIdx);
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| 
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|         // Skip over anything except register uses.
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|         if (!Op.isReg() || !Op.isUse() || !Op.getReg())
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|           continue;
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| 
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|         // Look for the defining instruction.
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|         unsigned Reg = Op.getReg();
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|         MachineInstr *DefInst = LastDef[Reg];
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|         if (!DefInst)
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|           continue;
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|         if (!isCombinableInstType(DefInst, TII, ShouldCombineAggressively))
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|           continue;
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| 
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|         // Only close newifiable stores should influence the decision.
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|         MachineBasicBlock::iterator It(DefInst);
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|         unsigned NumInstsToDef = 0;
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|         while (&*It++ != MI)
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|           ++NumInstsToDef;
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| 
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|         if (NumInstsToDef > MaxNumOfInstsBetweenNewValueStoreAndTFR)
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|           continue;
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| 
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|         PotentiallyNewifiableTFR.insert(DefInst);
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|       }
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|       // Skip to next instruction.
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|       continue;
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|     }
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| 
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|     // Put instructions that last defined integer or double registers into the
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|     // map.
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|     for (unsigned I = 0, E = MI->getNumOperands(); I != E; ++I) {
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|       MachineOperand &Op = MI->getOperand(I);
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|       if (!Op.isReg() || !Op.isDef() || !Op.getReg())
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|         continue;
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|       unsigned Reg = Op.getReg();
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|       if (Hexagon::DoubleRegsRegClass.contains(Reg)) {
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|         for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) {
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|           LastDef[*SubRegs] = MI;
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|         }
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|       } else if (Hexagon::IntRegsRegClass.contains(Reg))
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|         LastDef[Reg] = MI;
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|     }
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|   }
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| }
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| 
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| bool HexagonCopyToCombine::runOnMachineFunction(MachineFunction &MF) {
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| 
 | |
|   if (IsCombinesDisabled) return false;
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| 
 | |
|   bool HasChanged = false;
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| 
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|   // Get target info.
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|   TRI = MF.getSubtarget().getRegisterInfo();
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|   TII = static_cast<const HexagonInstrInfo *>(MF.getSubtarget().getInstrInfo());
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| 
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|   // Combine aggressively (for code size)
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|   ShouldCombineAggressively =
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|     MF.getTarget().getOptLevel() <= CodeGenOpt::Default;
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| 
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|   // Traverse basic blocks.
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|   for (MachineFunction::iterator BI = MF.begin(), BE = MF.end(); BI != BE;
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|        ++BI) {
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|     PotentiallyNewifiableTFR.clear();
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|     findPotentialNewifiableTFRs(*BI);
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| 
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|     // Traverse instructions in basic block.
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|     for(MachineBasicBlock::iterator MI = BI->begin(), End = BI->end();
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|         MI != End;) {
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|       MachineInstr *I1 = MI++;
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|       // Don't combine a TFR whose user could be newified (instructions that
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|       // define double registers can not be newified - Programmer's Ref Manual
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|       // 5.4.2 New-value stores).
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|       if (ShouldCombineAggressively && PotentiallyNewifiableTFR.count(I1))
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|         continue;
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| 
 | |
|       // Ignore instructions that are not combinable.
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|       if (!isCombinableInstType(I1, TII, ShouldCombineAggressively))
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|         continue;
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| 
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|       // Find a second instruction that can be merged into a combine
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|       // instruction.
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|       bool DoInsertAtI1 = false;
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|       MachineInstr *I2 = findPairable(I1, DoInsertAtI1);
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|       if (I2) {
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|         HasChanged = true;
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|         combine(I1, I2, MI, DoInsertAtI1);
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|       }
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|     }
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|   }
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| 
 | |
|   return HasChanged;
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| }
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| 
 | |
| /// findPairable - Returns an instruction that can be merged with \p I1 into a
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| /// COMBINE instruction or 0 if no such instruction can be found. Returns true
 | |
| /// in \p DoInsertAtI1 if the combine must be inserted at instruction \p I1
 | |
| /// false if the combine must be inserted at the returned instruction.
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| MachineInstr *HexagonCopyToCombine::findPairable(MachineInstr *I1,
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|                                                  bool &DoInsertAtI1) {
 | |
|   MachineBasicBlock::iterator I2 = std::next(MachineBasicBlock::iterator(I1));
 | |
|   unsigned I1DestReg = I1->getOperand(0).getReg();
 | |
| 
 | |
|   for (MachineBasicBlock::iterator End = I1->getParent()->end(); I2 != End;
 | |
|        ++I2) {
 | |
|     // Bail out early if we see a second definition of I1DestReg.
 | |
|     if (I2->modifiesRegister(I1DestReg, TRI))
 | |
|       break;
 | |
| 
 | |
|     // Ignore non-combinable instructions.
 | |
|     if (!isCombinableInstType(I2, TII, ShouldCombineAggressively))
 | |
|       continue;
 | |
| 
 | |
|     // Don't combine a TFR whose user could be newified.
 | |
|     if (ShouldCombineAggressively && PotentiallyNewifiableTFR.count(I2))
 | |
|       continue;
 | |
| 
 | |
|     unsigned I2DestReg = I2->getOperand(0).getReg();
 | |
| 
 | |
|     // Check that registers are adjacent and that the first destination register
 | |
|     // is even.
 | |
|     bool IsI1LowReg = (I2DestReg - I1DestReg) == 1;
 | |
|     bool IsI2LowReg = (I1DestReg - I2DestReg) == 1;
 | |
|     unsigned FirstRegIndex = IsI1LowReg ? I1DestReg : I2DestReg;
 | |
|     if ((!IsI1LowReg && !IsI2LowReg) || !isEvenReg(FirstRegIndex))
 | |
|       continue;
 | |
| 
 | |
|     // Check that the two instructions are combinable. V4 allows more
 | |
|     // instructions to be merged into a combine.
 | |
|     // The order matters because in a TFRI we might can encode a int8 as the
 | |
|     // hi reg operand but only a uint6 as the low reg operand.
 | |
|     if ((IsI2LowReg && !areCombinableOperations(TRI, I1, I2)) ||
 | |
|         (IsI1LowReg && !areCombinableOperations(TRI, I2, I1)))
 | |
|       break;
 | |
| 
 | |
|     if (isSafeToMoveTogether(I1, I2, I1DestReg, I2DestReg,
 | |
|                              DoInsertAtI1))
 | |
|       return I2;
 | |
| 
 | |
|     // Not safe. Stop searching.
 | |
|     break;
 | |
|   }
 | |
|   return nullptr;
 | |
| }
 | |
| 
 | |
| void HexagonCopyToCombine::combine(MachineInstr *I1, MachineInstr *I2,
 | |
|                                    MachineBasicBlock::iterator &MI,
 | |
|                                    bool DoInsertAtI1) {
 | |
|   // We are going to delete I2. If MI points to I2 advance it to the next
 | |
|   // instruction.
 | |
|   if ((MachineInstr *)MI == I2) ++MI;
 | |
| 
 | |
|   // Figure out whether I1 or I2 goes into the lowreg part.
 | |
|   unsigned I1DestReg = I1->getOperand(0).getReg();
 | |
|   unsigned I2DestReg = I2->getOperand(0).getReg();
 | |
|   bool IsI1Loreg = (I2DestReg - I1DestReg) == 1;
 | |
|   unsigned LoRegDef = IsI1Loreg ? I1DestReg : I2DestReg;
 | |
| 
 | |
|   // Get the double word register.
 | |
|   unsigned DoubleRegDest =
 | |
|     TRI->getMatchingSuperReg(LoRegDef, Hexagon::subreg_loreg,
 | |
|                              &Hexagon::DoubleRegsRegClass);
 | |
|   assert(DoubleRegDest != 0 && "Expect a valid register");
 | |
| 
 | |
| 
 | |
|   // Setup source operands.
 | |
|   MachineOperand &LoOperand = IsI1Loreg ? I1->getOperand(1) :
 | |
|     I2->getOperand(1);
 | |
|   MachineOperand &HiOperand = IsI1Loreg ? I2->getOperand(1) :
 | |
|     I1->getOperand(1);
 | |
| 
 | |
|   // Figure out which source is a register and which a constant.
 | |
|   bool IsHiReg = HiOperand.isReg();
 | |
|   bool IsLoReg = LoOperand.isReg();
 | |
| 
 | |
|   MachineBasicBlock::iterator InsertPt(DoInsertAtI1 ? I1 : I2);
 | |
|   // Emit combine.
 | |
|   if (IsHiReg && IsLoReg)
 | |
|     emitCombineRR(InsertPt, DoubleRegDest, HiOperand, LoOperand);
 | |
|   else if (IsHiReg)
 | |
|     emitCombineRI(InsertPt, DoubleRegDest, HiOperand, LoOperand);
 | |
|   else if (IsLoReg)
 | |
|     emitCombineIR(InsertPt, DoubleRegDest, HiOperand, LoOperand);
 | |
|   else
 | |
|     emitCombineII(InsertPt, DoubleRegDest, HiOperand, LoOperand);
 | |
| 
 | |
|   I1->eraseFromParent();
 | |
|   I2->eraseFromParent();
 | |
| }
 | |
| 
 | |
| void HexagonCopyToCombine::emitCombineII(MachineBasicBlock::iterator &InsertPt,
 | |
|                                          unsigned DoubleDestReg,
 | |
|                                          MachineOperand &HiOperand,
 | |
|                                          MachineOperand &LoOperand) {
 | |
|   DebugLoc DL = InsertPt->getDebugLoc();
 | |
|   MachineBasicBlock *BB = InsertPt->getParent();
 | |
| 
 | |
|   // Handle  globals.
 | |
|   if (HiOperand.isGlobal()) {
 | |
|     BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_Ii), DoubleDestReg)
 | |
|       .addGlobalAddress(HiOperand.getGlobal(), HiOperand.getOffset(),
 | |
|                         HiOperand.getTargetFlags())
 | |
|       .addImm(LoOperand.getImm());
 | |
|     return;
 | |
|   }
 | |
|   if (LoOperand.isGlobal()) {
 | |
|     BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_iI_V4), DoubleDestReg)
 | |
|       .addImm(HiOperand.getImm())
 | |
|       .addGlobalAddress(LoOperand.getGlobal(), LoOperand.getOffset(),
 | |
|                         LoOperand.getTargetFlags());
 | |
|     return;
 | |
|   }
 | |
| 
 | |
|   // Handle constant extended immediates.
 | |
|   if (!isInt<8>(HiOperand.getImm())) {
 | |
|     assert(isInt<8>(LoOperand.getImm()));
 | |
|     BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_Ii), DoubleDestReg)
 | |
|       .addImm(HiOperand.getImm())
 | |
|       .addImm(LoOperand.getImm());
 | |
|     return;
 | |
|   }
 | |
| 
 | |
|   if (!isUInt<6>(LoOperand.getImm())) {
 | |
|     assert(isInt<8>(HiOperand.getImm()));
 | |
|     BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_iI_V4), DoubleDestReg)
 | |
|       .addImm(HiOperand.getImm())
 | |
|       .addImm(LoOperand.getImm());
 | |
|     return;
 | |
|   }
 | |
| 
 | |
|   // Insert new combine instruction.
 | |
|   //  DoubleRegDest = combine #HiImm, #LoImm
 | |
|   BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_Ii), DoubleDestReg)
 | |
|     .addImm(HiOperand.getImm())
 | |
|     .addImm(LoOperand.getImm());
 | |
| }
 | |
| 
 | |
| void HexagonCopyToCombine::emitCombineIR(MachineBasicBlock::iterator &InsertPt,
 | |
|                                          unsigned DoubleDestReg,
 | |
|                                          MachineOperand &HiOperand,
 | |
|                                          MachineOperand &LoOperand) {
 | |
|   unsigned LoReg = LoOperand.getReg();
 | |
|   unsigned LoRegKillFlag = getKillRegState(LoOperand.isKill());
 | |
| 
 | |
|   DebugLoc DL = InsertPt->getDebugLoc();
 | |
|   MachineBasicBlock *BB = InsertPt->getParent();
 | |
| 
 | |
|   // Handle global.
 | |
|   if (HiOperand.isGlobal()) {
 | |
|     BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_Ir_V4), DoubleDestReg)
 | |
|       .addGlobalAddress(HiOperand.getGlobal(), HiOperand.getOffset(),
 | |
|                         HiOperand.getTargetFlags())
 | |
|       .addReg(LoReg, LoRegKillFlag);
 | |
|     return;
 | |
|   }
 | |
|   // Insert new combine instruction.
 | |
|   //  DoubleRegDest = combine #HiImm, LoReg
 | |
|   BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_Ir_V4), DoubleDestReg)
 | |
|     .addImm(HiOperand.getImm())
 | |
|     .addReg(LoReg, LoRegKillFlag);
 | |
| }
 | |
| 
 | |
| void HexagonCopyToCombine::emitCombineRI(MachineBasicBlock::iterator &InsertPt,
 | |
|                                          unsigned DoubleDestReg,
 | |
|                                          MachineOperand &HiOperand,
 | |
|                                          MachineOperand &LoOperand) {
 | |
|   unsigned HiRegKillFlag = getKillRegState(HiOperand.isKill());
 | |
|   unsigned HiReg = HiOperand.getReg();
 | |
| 
 | |
|   DebugLoc DL = InsertPt->getDebugLoc();
 | |
|   MachineBasicBlock *BB = InsertPt->getParent();
 | |
| 
 | |
|   // Handle global.
 | |
|   if (LoOperand.isGlobal()) {
 | |
|     BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_rI_V4), DoubleDestReg)
 | |
|       .addReg(HiReg, HiRegKillFlag)
 | |
|       .addGlobalAddress(LoOperand.getGlobal(), LoOperand.getOffset(),
 | |
|                         LoOperand.getTargetFlags());
 | |
|     return;
 | |
|   }
 | |
| 
 | |
|   // Insert new combine instruction.
 | |
|   //  DoubleRegDest = combine HiReg, #LoImm
 | |
|   BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_rI_V4), DoubleDestReg)
 | |
|     .addReg(HiReg, HiRegKillFlag)
 | |
|     .addImm(LoOperand.getImm());
 | |
| }
 | |
| 
 | |
| void HexagonCopyToCombine::emitCombineRR(MachineBasicBlock::iterator &InsertPt,
 | |
|                                          unsigned DoubleDestReg,
 | |
|                                          MachineOperand &HiOperand,
 | |
|                                          MachineOperand &LoOperand) {
 | |
|   unsigned LoRegKillFlag = getKillRegState(LoOperand.isKill());
 | |
|   unsigned HiRegKillFlag = getKillRegState(HiOperand.isKill());
 | |
|   unsigned LoReg = LoOperand.getReg();
 | |
|   unsigned HiReg = HiOperand.getReg();
 | |
| 
 | |
|   DebugLoc DL = InsertPt->getDebugLoc();
 | |
|   MachineBasicBlock *BB = InsertPt->getParent();
 | |
| 
 | |
|   // Insert new combine instruction.
 | |
|   //  DoubleRegDest = combine HiReg, LoReg
 | |
|   BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::COMBINE_rr), DoubleDestReg)
 | |
|     .addReg(HiReg, HiRegKillFlag)
 | |
|     .addReg(LoReg, LoRegKillFlag);
 | |
| }
 | |
| 
 | |
| FunctionPass *llvm::createHexagonCopyToCombine() {
 | |
|   return new HexagonCopyToCombine();
 | |
| }
 |