Index: LeonFloatOptimisations.cpp
===================================================================
--- LeonFloatOptimisations.cpp
+++ LeonFloatOptimisations.cpp
@@ -0,0 +1,167 @@
+//===------ LeonFloatOptimisations.cpp - Optimisations specific to LEON ---===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//
+//===----------------------------------------------------------------------===//
+
+#include "Sparc.h"
+#include "SparcSubtarget.h"
+#include "LeonPasses.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "leon-float-optimizer"
+
+STATISTIC(OptimisiedLeonFloatInstructions, "Number of LEON float instructions optimized");
+
+static cl::opt<bool> EnableLeonFloatOptimizer(
+  "enable-leon-float-optimiser",
+  cl::init(false),
+  cl::desc("Enable the LEON float optimiser."),
+  cl::Hidden);
+
+namespace {
+  struct ConvertDoubleFPToSingleFPInstr: public LEONMachineFunctionPass {
+    const SparcSubtarget *Subtarget;
+
+    static char ID;
+    ConvertDoubleFPToSingleFPInstr() : LEONMachineFunctionPass(ID) {}
+
+    const char *getPassName() const override {
+      return "LEON Float Instruction Optimizer";
+    }
+
+    bool runOnMachineFunction(MachineFunction &F) override;  };
+  char ConvertDoubleFPToSingleFPInstr::ID = 0;
+} // end of anonymous namespace
+
+/// createSparcDelaySlotOptimizerPass - Returns a pass that fills in delay
+/// slots in Sparc MachineFunctions
+///
+FunctionPass *llvm::createLeonFloatOptimizerPass(TargetMachine &tm) {
+  return new ConvertDoubleFPToSingleFPInstr;
+}
+
+//****************************************************************************************************************
+//**** ConvertDoubleFPToSingleFPInstr optimization pass
+//****************************************************************************************************************
+// This pass converts FDIVD to FDIVS and FSQRTD to FSQRTS
+//
+
+//ConvertDoubleFPToSingleFPInstr::ConvertDoubleFPToSingleFPInstr(
+//    TargetMachine &tm)
+//    : LEONMachineFunctionPass(tm, ID) {}
+
+bool ConvertDoubleFPToSingleFPInstr::runOnMachineFunction(MachineFunction &MF) {
+  Subtarget = &MF.getSubtarget<SparcSubtarget>();
+  const TargetInstrInfo &TII = *Subtarget->getInstrInfo();
+  DebugLoc DL = DebugLoc();
+
+  bool Modified = false;
+  for (auto MFI = MF.begin(), E = MF.end(); MFI != E; ++MFI) {
+    MachineBasicBlock &MBB = *MFI;
+    for (auto MBBI = MBB.begin(), E = MBB.end(); MBBI != E; ++MBBI) {
+      MachineInstr &MI = *MBBI;
+      unsigned Opcode = MI.getOpcode();
+
+      const int UNASSIGNED_INDEX = -1;
+
+      if (Opcode == SP::FDIVD && MI.getNumOperands() == 3) {
+        // take the registers from fdivd %f20,%f21,%f8
+        int Reg1Index = MI.getOperand(0).getReg();
+        int Reg2Index = MI.getOperand(1).getReg();
+        int Reg3Index = MI.getOperand(2).getReg();
+
+        clearUsedRegisterList();
+        MachineBasicBlock::iterator NMBBI = std::next(MBBI);
+
+        // Reg3Index hasn't been used yet, so we need to reserve it.
+        markRegisterUsed(Reg3Index);
+        const int ScratchReg1Index = getUnusedFPRegister(MF.getRegInfo());
+        markRegisterUsed(ScratchReg1Index);
+        const int ScratchReg2Index = getUnusedFPRegister(MF.getRegInfo());
+        markRegisterUsed(ScratchReg2Index);
+
+        if (ScratchReg1Index == UNASSIGNED_INDEX ||
+            ScratchReg2Index == UNASSIGNED_INDEX) {
+          errs() << "Cannot allocate free scratch registers for the "
+                    "ConvertDoubleFPToSingleFPInstr pass.\n";
+        } else {
+          // create fdtos %f20,%f0
+          BuildMI(MBB, MBBI, DL, TII.get(SP::FDTOS))
+              .addReg(ScratchReg1Index)
+              .addReg(Reg1Index);
+
+          // create fdtos %f21,%f2
+          BuildMI(MBB, MBBI, DL, TII.get(SP::FDTOS))
+              .addReg(ScratchReg2Index)
+              .addReg(Reg2Index);
+
+          // create fdivs %f0,%f2,%f8
+          BuildMI(MBB, MBBI, DL, TII.get(SP::FDIVS))
+              .addReg(Reg3Index)
+              .addReg(ScratchReg1Index)
+              .addReg(ScratchReg2Index);
+
+          MI.eraseFromParent();
+          MBBI = NMBBI;
+
+          Modified = true;
+        }
+      }
+
+      if (Opcode == SP::FSQRTD && MI.getNumOperands() == 2) {
+        // take the registers from fsqrtd %f20,%f21
+        int Reg1Index = MI.getOperand(0).getReg();
+        int Reg2Index = MI.getOperand(1).getReg();
+
+        clearUsedRegisterList();
+        MachineBasicBlock::iterator NMBBI = std::next(MBBI);
+
+        // Reg2Index hasn't been used yet, so we need to reserve it.
+        markRegisterUsed(Reg2Index);
+        const int ScratchReg1Index = getUnusedFPRegister(MF.getRegInfo());
+        markRegisterUsed(ScratchReg1Index);
+
+        if (ScratchReg1Index == UNASSIGNED_INDEX) {
+          errs() << "Cannot allocate free scratch registers for the "
+                    "ConvertDoubleFPToSingleFPInstr pass.\n";
+        } else {
+          // create fdtos %f20,%f0
+          BuildMI(MBB, MBBI, DL, TII.get(SP::FDTOS))
+              .addReg(ScratchReg1Index)
+              .addReg(Reg1Index);
+
+          // create fsqrts %f0,%f2
+          BuildMI(MBB, MBBI, DL, TII.get(SP::FSQRTS))
+              .addReg(Reg2Index)
+              .addReg(ScratchReg1Index);
+
+          MI.eraseFromParent();
+          MBBI = NMBBI;
+
+          Modified = true;
+        }
+      }
+    }
+  }
+
+  return Modified;
+}
+
+
Index: Sparc.h
===================================================================
--- Sparc.h
+++ Sparc.h
@@ -29,6 +29,7 @@
 
   FunctionPass *createSparcISelDag(SparcTargetMachine &TM);
   FunctionPass *createSparcDelaySlotFillerPass(TargetMachine &TM);
+  FunctionPass *createLeonFloatOptimizerPass(TargetMachine &TM);
 
   void LowerSparcMachineInstrToMCInst(const MachineInstr *MI,
                                       MCInst &OutMI,