diff options
Diffstat (limited to 'lib/Target/ARM/ARMLoadStoreOptimizer.cpp')
| -rw-r--r-- | lib/Target/ARM/ARMLoadStoreOptimizer.cpp | 120 |
1 files changed, 55 insertions, 65 deletions
diff --git a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp index 5b62a21706ce..46ff326ba630 100644 --- a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp +++ b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp @@ -7,8 +7,8 @@ // //===----------------------------------------------------------------------===// // -// This file contains a pass that performs load / store related peephole -// optimizations. This pass should be run after register allocation. +/// \file This file contains a pass that performs load / store related peephole +/// optimizations. This pass should be run after register allocation. // //===----------------------------------------------------------------------===// @@ -58,10 +58,9 @@ STATISTIC(NumSTRD2STM, "Number of strd instructions turned back into stm"); STATISTIC(NumLDRD2LDR, "Number of ldrd instructions turned back into ldr's"); STATISTIC(NumSTRD2STR, "Number of strd instructions turned back into str's"); -/// ARMAllocLoadStoreOpt - Post- register allocation pass the combine -/// load / store instructions to form ldm / stm instructions. - namespace { + /// Post- register allocation pass the combine load / store instructions to + /// form ldm / stm instructions. struct ARMLoadStoreOpt : public MachineFunctionPass { static char ID; ARMLoadStoreOpt() : MachineFunctionPass(ID) {} @@ -271,10 +270,7 @@ static int getLoadStoreMultipleOpcode(unsigned Opcode, ARM_AM::AMSubMode Mode) { } } -namespace llvm { - namespace ARM_AM { - -AMSubMode getLoadStoreMultipleSubMode(unsigned Opcode) { +static ARM_AM::AMSubMode getLoadStoreMultipleSubMode(unsigned Opcode) { switch (Opcode) { default: llvm_unreachable("Unhandled opcode!"); case ARM::LDMIA_RET: @@ -328,9 +324,6 @@ AMSubMode getLoadStoreMultipleSubMode(unsigned Opcode) { } } - } // end namespace ARM_AM -} // end namespace llvm - static bool isT1i32Load(unsigned Opc) { return Opc == ARM::tLDRi || Opc == ARM::tLDRspi; } @@ -469,9 +462,9 @@ ARMLoadStoreOpt::UpdateBaseRegUses(MachineBasicBlock &MBB, } } -/// MergeOps - Create and insert a LDM or STM with Base as base register and -/// registers in Regs as the register operands that would be loaded / stored. -/// It returns true if the transformation is done. +/// Create and insert a LDM or STM with Base as base register and registers in +/// Regs as the register operands that would be loaded / stored. It returns +/// true if the transformation is done. bool ARMLoadStoreOpt::MergeOps(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, @@ -665,7 +658,7 @@ ARMLoadStoreOpt::MergeOps(MachineBasicBlock &MBB, return true; } -/// \brief Find all instructions using a given imp-def within a range. +/// Find all instructions using a given imp-def within a range. /// /// We are trying to combine a range of instructions, one of which (located at /// position RangeBegin) implicitly defines a register. The final LDM/STM will @@ -721,8 +714,7 @@ void ARMLoadStoreOpt::findUsesOfImpDef( } } -// MergeOpsUpdate - call MergeOps and update MemOps and merges accordingly on -// success. +/// Call MergeOps and update MemOps and merges accordingly on success. void ARMLoadStoreOpt::MergeOpsUpdate(MachineBasicBlock &MBB, MemOpQueue &memOps, unsigned memOpsBegin, unsigned memOpsEnd, @@ -762,10 +754,10 @@ void ARMLoadStoreOpt::MergeOpsUpdate(MachineBasicBlock &MBB, Regs.push_back(std::make_pair(Reg, isKill)); // Collect any implicit defs of super-registers. They must be preserved. - for (MIOperands MO(memOps[i].MBBI); MO.isValid(); ++MO) { - if (!MO->isReg() || !MO->isDef() || !MO->isImplicit() || MO->isDead()) + for (const MachineOperand &MO : memOps[i].MBBI->operands()) { + if (!MO.isReg() || !MO.isDef() || !MO.isImplicit() || MO.isDead()) continue; - unsigned DefReg = MO->getReg(); + unsigned DefReg = MO.getReg(); if (std::find(ImpDefs.begin(), ImpDefs.end(), DefReg) == ImpDefs.end()) ImpDefs.push_back(DefReg); @@ -823,8 +815,8 @@ void ARMLoadStoreOpt::MergeOpsUpdate(MachineBasicBlock &MBB, } } -/// MergeLDR_STR - Merge a number of load / store instructions into one or more -/// load / store multiple instructions. +/// Merge a number of load / store instructions into one or more load / store +/// multiple instructions. void ARMLoadStoreOpt::MergeLDR_STR(MachineBasicBlock &MBB, unsigned SIndex, unsigned Base, unsigned Opcode, unsigned Size, @@ -1083,8 +1075,8 @@ static unsigned getUpdatingLSMultipleOpcode(unsigned Opc, } } -/// MergeBaseUpdateLSMultiple - Fold proceeding/trailing inc/dec of base -/// register into the LDM/STM/VLDM{D|S}/VSTM{D|S} op when possible: +/// Fold proceeding/trailing inc/dec of base register into the +/// LDM/STM/VLDM{D|S}/VSTM{D|S} op when possible: /// /// stmia rn, <ra, rb, rc> /// rn := rn + 4 * 3; @@ -1118,7 +1110,7 @@ bool ARMLoadStoreOpt::MergeBaseUpdateLSMultiple(MachineBasicBlock &MBB, return false; bool DoMerge = false; - ARM_AM::AMSubMode Mode = ARM_AM::getLoadStoreMultipleSubMode(Opcode); + ARM_AM::AMSubMode Mode = getLoadStoreMultipleSubMode(Opcode); // Try merging with the previous instruction. MachineBasicBlock::iterator BeginMBBI = MBB.begin(); @@ -1231,8 +1223,8 @@ static unsigned getPostIndexedLoadStoreOpcode(unsigned Opc, } } -/// MergeBaseUpdateLoadStore - Fold proceeding/trailing inc/dec of base -/// register into the LDR/STR/FLD{D|S}/FST{D|S} op when possible: +/// Fold proceeding/trailing inc/dec of base register into the +/// LDR/STR/FLD{D|S}/FST{D|S} op when possible: bool ARMLoadStoreOpt::MergeBaseUpdateLoadStore(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, const TargetInstrInfo *TII, @@ -1373,8 +1365,8 @@ bool ARMLoadStoreOpt::MergeBaseUpdateLoadStore(MachineBasicBlock &MBB, return true; } -/// isMemoryOp - Returns true if instruction is a memory operation that this -/// pass is capable of operating on. +/// Returns true if instruction is a memory operation that this pass is capable +/// of operating on. static bool isMemoryOp(const MachineInstr *MI) { // When no memory operands are present, conservatively assume unaligned, // volatile, unfoldable. @@ -1428,8 +1420,8 @@ static bool isMemoryOp(const MachineInstr *MI) { return false; } -/// AdvanceRS - Advance register scavenger to just before the earliest memory -/// op that is being merged. +/// Advance register scavenger to just before the earliest memory op that is +/// being merged. void ARMLoadStoreOpt::AdvanceRS(MachineBasicBlock &MBB, MemOpQueue &MemOps) { MachineBasicBlock::iterator Loc = MemOps[0].MBBI; unsigned Position = MemOps[0].Position; @@ -1472,8 +1464,7 @@ bool ARMLoadStoreOpt::FixInvalidRegPairOp(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI) { MachineInstr *MI = &*MBBI; unsigned Opcode = MI->getOpcode(); - if (Opcode == ARM::LDRD || Opcode == ARM::STRD || - Opcode == ARM::t2LDRDi8 || Opcode == ARM::t2STRDi8) { + if (Opcode == ARM::LDRD || Opcode == ARM::STRD) { const MachineOperand &BaseOp = MI->getOperand(2); unsigned BaseReg = BaseOp.getReg(); unsigned EvenReg = MI->getOperand(0).getReg(); @@ -1588,8 +1579,8 @@ bool ARMLoadStoreOpt::FixInvalidRegPairOp(MachineBasicBlock &MBB, return false; } -/// LoadStoreMultipleOpti - An optimization pass to turn multiple LDR / STR -/// ops of the same base and incrementing offset into LDM / STM ops. +/// An optimization pass to turn multiple LDR / STR ops of the same base and +/// incrementing offset into LDM / STM ops. bool ARMLoadStoreOpt::LoadStoreMultipleOpti(MachineBasicBlock &MBB) { unsigned NumMerges = 0; unsigned NumMemOps = 0; @@ -1770,9 +1761,9 @@ bool ARMLoadStoreOpt::LoadStoreMultipleOpti(MachineBasicBlock &MBB) { return NumMerges > 0; } -/// MergeReturnIntoLDM - If this is a exit BB, try merging the return ops -/// ("bx lr" and "mov pc, lr") into the preceding stack restore so it -/// directly restore the value of LR into pc. +/// If this is a exit BB, try merging the return ops ("bx lr" and "mov pc, lr") +/// into the preceding stack restore so it directly restore the value of LR +/// into pc. /// ldmfd sp!, {..., lr} /// bx lr /// or @@ -1834,12 +1825,9 @@ bool ARMLoadStoreOpt::runOnMachineFunction(MachineFunction &Fn) { return Modified; } - -/// ARMPreAllocLoadStoreOpt - Pre- register allocation pass that move -/// load / stores from consecutive locations close to make it more -/// likely they will be combined later. - namespace { + /// Pre- register allocation pass that move load / stores from consecutive + /// locations close to make it more likely they will be combined later. struct ARMPreAllocLoadStoreOpt : public MachineFunctionPass{ static char ID; ARMPreAllocLoadStoreOpt() : MachineFunctionPass(ID) {} @@ -1936,7 +1924,7 @@ static bool IsSafeAndProfitableToMove(bool isLd, unsigned Base, } -/// Copy Op0 and Op1 operands into a new array assigned to MI. +/// Copy \p Op0 and \p Op1 operands into a new array assigned to MI. static void concatenateMemOperands(MachineInstr *MI, MachineInstr *Op0, MachineInstr *Op1) { assert(MI->memoperands_empty() && "expected a new machineinstr"); @@ -1954,10 +1942,11 @@ static void concatenateMemOperands(MachineInstr *MI, MachineInstr *Op0, bool ARMPreAllocLoadStoreOpt::CanFormLdStDWord(MachineInstr *Op0, MachineInstr *Op1, - DebugLoc &dl, - unsigned &NewOpc, unsigned &EvenReg, - unsigned &OddReg, unsigned &BaseReg, - int &Offset, unsigned &PredReg, + DebugLoc &dl, unsigned &NewOpc, + unsigned &FirstReg, + unsigned &SecondReg, + unsigned &BaseReg, int &Offset, + unsigned &PredReg, ARMCC::CondCodes &Pred, bool &isT2) { // Make sure we're allowed to generate LDRD/STRD. @@ -2016,9 +2005,9 @@ ARMPreAllocLoadStoreOpt::CanFormLdStDWord(MachineInstr *Op0, MachineInstr *Op1, return false; Offset = ARM_AM::getAM3Opc(AddSub, OffImm); } - EvenReg = Op0->getOperand(0).getReg(); - OddReg = Op1->getOperand(0).getReg(); - if (EvenReg == OddReg) + FirstReg = Op0->getOperand(0).getReg(); + SecondReg = Op1->getOperand(0).getReg(); + if (FirstReg == SecondReg) return false; BaseReg = Op0->getOperand(1).getReg(); Pred = getInstrPredicate(Op0, PredReg); @@ -2114,7 +2103,7 @@ bool ARMPreAllocLoadStoreOpt::RescheduleOps(MachineBasicBlock *MBB, // to try to allocate a pair of registers that can form register pairs. MachineInstr *Op0 = Ops.back(); MachineInstr *Op1 = Ops[Ops.size()-2]; - unsigned EvenReg = 0, OddReg = 0; + unsigned FirstReg = 0, SecondReg = 0; unsigned BaseReg = 0, PredReg = 0; ARMCC::CondCodes Pred = ARMCC::AL; bool isT2 = false; @@ -2122,21 +2111,21 @@ bool ARMPreAllocLoadStoreOpt::RescheduleOps(MachineBasicBlock *MBB, int Offset = 0; DebugLoc dl; if (NumMove == 2 && CanFormLdStDWord(Op0, Op1, dl, NewOpc, - EvenReg, OddReg, BaseReg, + FirstReg, SecondReg, BaseReg, Offset, PredReg, Pred, isT2)) { Ops.pop_back(); Ops.pop_back(); const MCInstrDesc &MCID = TII->get(NewOpc); const TargetRegisterClass *TRC = TII->getRegClass(MCID, 0, TRI, *MF); - MRI->constrainRegClass(EvenReg, TRC); - MRI->constrainRegClass(OddReg, TRC); + MRI->constrainRegClass(FirstReg, TRC); + MRI->constrainRegClass(SecondReg, TRC); // Form the pair instruction. if (isLd) { MachineInstrBuilder MIB = BuildMI(*MBB, InsertPos, dl, MCID) - .addReg(EvenReg, RegState::Define) - .addReg(OddReg, RegState::Define) + .addReg(FirstReg, RegState::Define) + .addReg(SecondReg, RegState::Define) .addReg(BaseReg); // FIXME: We're converting from LDRi12 to an insn that still // uses addrmode2, so we need an explicit offset reg. It should @@ -2149,8 +2138,8 @@ bool ARMPreAllocLoadStoreOpt::RescheduleOps(MachineBasicBlock *MBB, ++NumLDRDFormed; } else { MachineInstrBuilder MIB = BuildMI(*MBB, InsertPos, dl, MCID) - .addReg(EvenReg) - .addReg(OddReg) + .addReg(FirstReg) + .addReg(SecondReg) .addReg(BaseReg); // FIXME: We're converting from LDRi12 to an insn that still // uses addrmode2, so we need an explicit offset reg. It should @@ -2165,9 +2154,11 @@ bool ARMPreAllocLoadStoreOpt::RescheduleOps(MachineBasicBlock *MBB, MBB->erase(Op0); MBB->erase(Op1); - // Add register allocation hints to form register pairs. - MRI->setRegAllocationHint(EvenReg, ARMRI::RegPairEven, OddReg); - MRI->setRegAllocationHint(OddReg, ARMRI::RegPairOdd, EvenReg); + if (!isT2) { + // Add register allocation hints to form register pairs. + MRI->setRegAllocationHint(FirstReg, ARMRI::RegPairEven, SecondReg); + MRI->setRegAllocationHint(SecondReg, ARMRI::RegPairOdd, FirstReg); + } } else { for (unsigned i = 0; i != NumMove; ++i) { MachineInstr *Op = Ops.back(); @@ -2292,8 +2283,7 @@ ARMPreAllocLoadStoreOpt::RescheduleLoadStoreInstrs(MachineBasicBlock *MBB) { } -/// createARMLoadStoreOptimizationPass - returns an instance of the load / store -/// optimization pass. +/// Returns an instance of the load / store optimization pass. FunctionPass *llvm::createARMLoadStoreOptimizationPass(bool PreAlloc) { if (PreAlloc) return new ARMPreAllocLoadStoreOpt(); |