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Diffstat (limited to 'contrib/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp')
-rw-r--r-- | contrib/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp b/contrib/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp new file mode 100644 index 0000000..a2b615d --- /dev/null +++ b/contrib/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp @@ -0,0 +1,77 @@ +//===-- DelaySlotFiller.cpp - Mips delay slot filler ---------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// Simple pass to fills delay slots with NOPs. +// +//===----------------------------------------------------------------------===// + +#define DEBUG_TYPE "delay-slot-filler" + +#include "Mips.h" +#include "MipsTargetMachine.h" +#include "llvm/CodeGen/MachineFunctionPass.h" +#include "llvm/CodeGen/MachineInstrBuilder.h" +#include "llvm/Target/TargetInstrInfo.h" +#include "llvm/ADT/Statistic.h" + +using namespace llvm; + +STATISTIC(FilledSlots, "Number of delay slots filled"); + +namespace { + struct Filler : public MachineFunctionPass { + + TargetMachine &TM; + const TargetInstrInfo *TII; + + static char ID; + Filler(TargetMachine &tm) + : MachineFunctionPass(&ID), TM(tm), TII(tm.getInstrInfo()) { } + + virtual const char *getPassName() const { + return "Mips Delay Slot Filler"; + } + + bool runOnMachineBasicBlock(MachineBasicBlock &MBB); + bool runOnMachineFunction(MachineFunction &F) { + bool Changed = false; + for (MachineFunction::iterator FI = F.begin(), FE = F.end(); + FI != FE; ++FI) + Changed |= runOnMachineBasicBlock(*FI); + return Changed; + } + + }; + char Filler::ID = 0; +} // end of anonymous namespace + +/// runOnMachineBasicBlock - Fill in delay slots for the given basic block. +/// Currently, we fill delay slots with NOPs. We assume there is only one +/// delay slot per delayed instruction. +bool Filler:: +runOnMachineBasicBlock(MachineBasicBlock &MBB) +{ + bool Changed = false; + for (MachineBasicBlock::iterator I = MBB.begin(); I != MBB.end(); ++I) + if (I->getDesc().hasDelaySlot()) { + MachineBasicBlock::iterator J = I; + ++J; + BuildMI(MBB, J, I->getDebugLoc(), TII->get(Mips::NOP)); + ++FilledSlots; + Changed = true; + } + return Changed; +} + +/// createMipsDelaySlotFillerPass - Returns a pass that fills in delay +/// slots in Mips MachineFunctions +FunctionPass *llvm::createMipsDelaySlotFillerPass(MipsTargetMachine &tm) { + return new Filler(tm); +} + |