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- #pragma once
- #ifdef __GNUC__
- #pragma GCC diagnostic push
- #pragma GCC diagnostic ignored "-Wunused-parameter"
- #endif
- //=- llvm/CodeGen/GlobalISel/RegBankSelect.h - Reg Bank Selector --*- C++ -*-=//
- //
- // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
- // See https://llvm.org/LICENSE.txt for license information.
- // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
- //
- //===----------------------------------------------------------------------===//
- //
- /// \file
- /// This file describes the interface of the MachineFunctionPass
- /// responsible for assigning the generic virtual registers to register bank.
- ///
- /// By default, the reg bank selector relies on local decisions to
- /// assign the register bank. In other words, it looks at one instruction
- /// at a time to decide where the operand of that instruction should live.
- ///
- /// At higher optimization level, we could imagine that the reg bank selector
- /// would use more global analysis and do crazier thing like duplicating
- /// instructions and so on. This is future work.
- ///
- /// For now, the pass uses a greedy algorithm to decide where the operand
- /// of an instruction should live. It asks the target which banks may be
- /// used for each operand of the instruction and what is the cost. Then,
- /// it chooses the solution which minimize the cost of the instruction plus
- /// the cost of any move that may be needed to the values into the right
- /// register bank.
- /// In other words, the cost for an instruction on a register bank RegBank
- /// is: Cost of I on RegBank plus the sum of the cost for bringing the
- /// input operands from their current register bank to RegBank.
- /// Thus, the following formula:
- /// cost(I, RegBank) = cost(I.Opcode, RegBank) +
- /// sum(for each arg in I.arguments: costCrossCopy(arg.RegBank, RegBank))
- ///
- /// E.g., Let say we are assigning the register bank for the instruction
- /// defining v2.
- /// v0(A_REGBANK) = ...
- /// v1(A_REGBANK) = ...
- /// v2 = G_ADD i32 v0, v1 <-- MI
- ///
- /// The target may say it can generate G_ADD i32 on register bank A and B
- /// with a cost of respectively 5 and 1.
- /// Then, let say the cost of a cross register bank copies from A to B is 1.
- /// The reg bank selector would compare the following two costs:
- /// cost(MI, A_REGBANK) = cost(G_ADD, A_REGBANK) + cost(v0.RegBank, A_REGBANK) +
- /// cost(v1.RegBank, A_REGBANK)
- /// = 5 + cost(A_REGBANK, A_REGBANK) + cost(A_REGBANK,
- /// A_REGBANK)
- /// = 5 + 0 + 0 = 5
- /// cost(MI, B_REGBANK) = cost(G_ADD, B_REGBANK) + cost(v0.RegBank, B_REGBANK) +
- /// cost(v1.RegBank, B_REGBANK)
- /// = 1 + cost(A_REGBANK, B_REGBANK) + cost(A_REGBANK,
- /// B_REGBANK)
- /// = 1 + 1 + 1 = 3
- /// Therefore, in this specific example, the reg bank selector would choose
- /// bank B for MI.
- /// v0(A_REGBANK) = ...
- /// v1(A_REGBANK) = ...
- /// tmp0(B_REGBANK) = COPY v0
- /// tmp1(B_REGBANK) = COPY v1
- /// v2(B_REGBANK) = G_ADD i32 tmp0, tmp1
- //
- //===----------------------------------------------------------------------===//
- #ifndef LLVM_CODEGEN_GLOBALISEL_REGBANKSELECT_H
- #define LLVM_CODEGEN_GLOBALISEL_REGBANKSELECT_H
- #include "llvm/ADT/SmallVector.h"
- #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
- #include "llvm/CodeGen/GlobalISel/RegisterBankInfo.h"
- #include "llvm/CodeGen/MachineBasicBlock.h"
- #include "llvm/CodeGen/MachineFunctionPass.h"
- #include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
- #include <cassert>
- #include <cstdint>
- #include <memory>
- namespace llvm {
- class BlockFrequency;
- class MachineBlockFrequencyInfo;
- class MachineBranchProbabilityInfo;
- class MachineOperand;
- class MachineRegisterInfo;
- class Pass;
- class raw_ostream;
- class TargetPassConfig;
- class TargetRegisterInfo;
- /// This pass implements the reg bank selector pass used in the GlobalISel
- /// pipeline. At the end of this pass, all register operands have been assigned
- class RegBankSelect : public MachineFunctionPass {
- public:
- static char ID;
- /// List of the modes supported by the RegBankSelect pass.
- enum Mode {
- /// Assign the register banks as fast as possible (default).
- Fast,
- /// Greedily minimize the cost of assigning register banks.
- /// This should produce code of greater quality, but will
- /// require more compile time.
- Greedy
- };
- /// Abstract class used to represent an insertion point in a CFG.
- /// This class records an insertion point and materializes it on
- /// demand.
- /// It allows to reason about the frequency of this insertion point,
- /// without having to logically materialize it (e.g., on an edge),
- /// before we actually need to insert something.
- class InsertPoint {
- protected:
- /// Tell if the insert point has already been materialized.
- bool WasMaterialized = false;
- /// Materialize the insertion point.
- ///
- /// If isSplit() is true, this involves actually splitting
- /// the block or edge.
- ///
- /// \post getPointImpl() returns a valid iterator.
- /// \post getInsertMBBImpl() returns a valid basic block.
- /// \post isSplit() == false ; no more splitting should be required.
- virtual void materialize() = 0;
- /// Return the materialized insertion basic block.
- /// Code will be inserted into that basic block.
- ///
- /// \pre ::materialize has been called.
- virtual MachineBasicBlock &getInsertMBBImpl() = 0;
- /// Return the materialized insertion point.
- /// Code will be inserted before that point.
- ///
- /// \pre ::materialize has been called.
- virtual MachineBasicBlock::iterator getPointImpl() = 0;
- public:
- virtual ~InsertPoint() = default;
- /// The first call to this method will cause the splitting to
- /// happen if need be, then sub sequent calls just return
- /// the iterator to that point. I.e., no more splitting will
- /// occur.
- ///
- /// \return The iterator that should be used with
- /// MachineBasicBlock::insert. I.e., additional code happens
- /// before that point.
- MachineBasicBlock::iterator getPoint() {
- if (!WasMaterialized) {
- WasMaterialized = true;
- assert(canMaterialize() && "Impossible to materialize this point");
- materialize();
- }
- // When we materialized the point we should have done the splitting.
- assert(!isSplit() && "Wrong pre-condition");
- return getPointImpl();
- }
- /// The first call to this method will cause the splitting to
- /// happen if need be, then sub sequent calls just return
- /// the basic block that contains the insertion point.
- /// I.e., no more splitting will occur.
- ///
- /// \return The basic block should be used with
- /// MachineBasicBlock::insert and ::getPoint. The new code should
- /// happen before that point.
- MachineBasicBlock &getInsertMBB() {
- if (!WasMaterialized) {
- WasMaterialized = true;
- assert(canMaterialize() && "Impossible to materialize this point");
- materialize();
- }
- // When we materialized the point we should have done the splitting.
- assert(!isSplit() && "Wrong pre-condition");
- return getInsertMBBImpl();
- }
- /// Insert \p MI in the just before ::getPoint()
- MachineBasicBlock::iterator insert(MachineInstr &MI) {
- return getInsertMBB().insert(getPoint(), &MI);
- }
- /// Does this point involve splitting an edge or block?
- /// As soon as ::getPoint is called and thus, the point
- /// materialized, the point will not require splitting anymore,
- /// i.e., this will return false.
- virtual bool isSplit() const { return false; }
- /// Frequency of the insertion point.
- /// \p P is used to access the various analysis that will help to
- /// get that information, like MachineBlockFrequencyInfo. If \p P
- /// does not contain enough enough to return the actual frequency,
- /// this returns 1.
- virtual uint64_t frequency(const Pass &P) const { return 1; }
- /// Check whether this insertion point can be materialized.
- /// As soon as ::getPoint is called and thus, the point materialized
- /// calling this method does not make sense.
- virtual bool canMaterialize() const { return false; }
- };
- /// Insertion point before or after an instruction.
- class InstrInsertPoint : public InsertPoint {
- private:
- /// Insertion point.
- MachineInstr &Instr;
- /// Does the insertion point is before or after Instr.
- bool Before;
- void materialize() override;
- MachineBasicBlock::iterator getPointImpl() override {
- if (Before)
- return Instr;
- return Instr.getNextNode() ? *Instr.getNextNode()
- : Instr.getParent()->end();
- }
- MachineBasicBlock &getInsertMBBImpl() override {
- return *Instr.getParent();
- }
- public:
- /// Create an insertion point before (\p Before=true) or after \p Instr.
- InstrInsertPoint(MachineInstr &Instr, bool Before = true);
- bool isSplit() const override;
- uint64_t frequency(const Pass &P) const override;
- // Worst case, we need to slice the basic block, but that is still doable.
- bool canMaterialize() const override { return true; }
- };
- /// Insertion point at the beginning or end of a basic block.
- class MBBInsertPoint : public InsertPoint {
- private:
- /// Insertion point.
- MachineBasicBlock &MBB;
- /// Does the insertion point is at the beginning or end of MBB.
- bool Beginning;
- void materialize() override { /*Nothing to do to materialize*/
- }
- MachineBasicBlock::iterator getPointImpl() override {
- return Beginning ? MBB.begin() : MBB.end();
- }
- MachineBasicBlock &getInsertMBBImpl() override { return MBB; }
- public:
- MBBInsertPoint(MachineBasicBlock &MBB, bool Beginning = true)
- : MBB(MBB), Beginning(Beginning) {
- // If we try to insert before phis, we should use the insertion
- // points on the incoming edges.
- assert((!Beginning || MBB.getFirstNonPHI() == MBB.begin()) &&
- "Invalid beginning point");
- // If we try to insert after the terminators, we should use the
- // points on the outcoming edges.
- assert((Beginning || MBB.getFirstTerminator() == MBB.end()) &&
- "Invalid end point");
- }
- bool isSplit() const override { return false; }
- uint64_t frequency(const Pass &P) const override;
- bool canMaterialize() const override { return true; };
- };
- /// Insertion point on an edge.
- class EdgeInsertPoint : public InsertPoint {
- private:
- /// Source of the edge.
- MachineBasicBlock &Src;
- /// Destination of the edge.
- /// After the materialization is done, this hold the basic block
- /// that resulted from the splitting.
- MachineBasicBlock *DstOrSplit;
- /// P is used to update the analysis passes as applicable.
- Pass &P;
- void materialize() override;
- MachineBasicBlock::iterator getPointImpl() override {
- // DstOrSplit should be the Split block at this point.
- // I.e., it should have one predecessor, Src, and one successor,
- // the original Dst.
- assert(DstOrSplit && DstOrSplit->isPredecessor(&Src) &&
- DstOrSplit->pred_size() == 1 && DstOrSplit->succ_size() == 1 &&
- "Did not split?!");
- return DstOrSplit->begin();
- }
- MachineBasicBlock &getInsertMBBImpl() override { return *DstOrSplit; }
- public:
- EdgeInsertPoint(MachineBasicBlock &Src, MachineBasicBlock &Dst, Pass &P)
- : Src(Src), DstOrSplit(&Dst), P(P) {}
- bool isSplit() const override {
- return Src.succ_size() > 1 && DstOrSplit->pred_size() > 1;
- }
- uint64_t frequency(const Pass &P) const override;
- bool canMaterialize() const override;
- };
- /// Struct used to represent the placement of a repairing point for
- /// a given operand.
- class RepairingPlacement {
- public:
- /// Define the kind of action this repairing needs.
- enum RepairingKind {
- /// Nothing to repair, just drop this action.
- None,
- /// Reparing code needs to happen before InsertPoints.
- Insert,
- /// (Re)assign the register bank of the operand.
- Reassign,
- /// Mark this repairing placement as impossible.
- Impossible
- };
- /// \name Convenient types for a list of insertion points.
- /// @{
- using InsertionPoints = SmallVector<std::unique_ptr<InsertPoint>, 2>;
- using insertpt_iterator = InsertionPoints::iterator;
- using const_insertpt_iterator = InsertionPoints::const_iterator;
- /// @}
- private:
- /// Kind of repairing.
- RepairingKind Kind;
- /// Index of the operand that will be repaired.
- unsigned OpIdx;
- /// Are all the insert points materializeable?
- bool CanMaterialize;
- /// Is there any of the insert points needing splitting?
- bool HasSplit = false;
- /// Insertion point for the repair code.
- /// The repairing code needs to happen just before these points.
- InsertionPoints InsertPoints;
- /// Some insertion points may need to update the liveness and such.
- Pass &P;
- public:
- /// Create a repairing placement for the \p OpIdx-th operand of
- /// \p MI. \p TRI is used to make some checks on the register aliases
- /// if the machine operand is a physical register. \p P is used to
- /// to update liveness information and such when materializing the
- /// points.
- RepairingPlacement(MachineInstr &MI, unsigned OpIdx,
- const TargetRegisterInfo &TRI, Pass &P,
- RepairingKind Kind = RepairingKind::Insert);
- /// \name Getters.
- /// @{
- RepairingKind getKind() const { return Kind; }
- unsigned getOpIdx() const { return OpIdx; }
- bool canMaterialize() const { return CanMaterialize; }
- bool hasSplit() { return HasSplit; }
- /// @}
- /// \name Overloaded methods to add an insertion point.
- /// @{
- /// Add a MBBInsertionPoint to the list of InsertPoints.
- void addInsertPoint(MachineBasicBlock &MBB, bool Beginning);
- /// Add a InstrInsertionPoint to the list of InsertPoints.
- void addInsertPoint(MachineInstr &MI, bool Before);
- /// Add an EdgeInsertionPoint (\p Src, \p Dst) to the list of InsertPoints.
- void addInsertPoint(MachineBasicBlock &Src, MachineBasicBlock &Dst);
- /// Add an InsertPoint to the list of insert points.
- /// This method takes the ownership of &\p Point.
- void addInsertPoint(InsertPoint &Point);
- /// @}
- /// \name Accessors related to the insertion points.
- /// @{
- insertpt_iterator begin() { return InsertPoints.begin(); }
- insertpt_iterator end() { return InsertPoints.end(); }
- const_insertpt_iterator begin() const { return InsertPoints.begin(); }
- const_insertpt_iterator end() const { return InsertPoints.end(); }
- unsigned getNumInsertPoints() const { return InsertPoints.size(); }
- /// @}
- /// Change the type of this repairing placement to \p NewKind.
- /// It is not possible to switch a repairing placement to the
- /// RepairingKind::Insert. There is no fundamental problem with
- /// that, but no uses as well, so do not support it for now.
- ///
- /// \pre NewKind != RepairingKind::Insert
- /// \post getKind() == NewKind
- void switchTo(RepairingKind NewKind) {
- assert(NewKind != Kind && "Already of the right Kind");
- Kind = NewKind;
- InsertPoints.clear();
- CanMaterialize = NewKind != RepairingKind::Impossible;
- HasSplit = false;
- assert(NewKind != RepairingKind::Insert &&
- "We would need more MI to switch to Insert");
- }
- };
- private:
- /// Helper class used to represent the cost for mapping an instruction.
- /// When mapping an instruction, we may introduce some repairing code.
- /// In most cases, the repairing code is local to the instruction,
- /// thus, we can omit the basic block frequency from the cost.
- /// However, some alternatives may produce non-local cost, e.g., when
- /// repairing a phi, and thus we then need to scale the local cost
- /// to the non-local cost. This class does this for us.
- /// \note: We could simply always scale the cost. The problem is that
- /// there are higher chances that we saturate the cost easier and end
- /// up having the same cost for actually different alternatives.
- /// Another option would be to use APInt everywhere.
- class MappingCost {
- private:
- /// Cost of the local instructions.
- /// This cost is free of basic block frequency.
- uint64_t LocalCost = 0;
- /// Cost of the non-local instructions.
- /// This cost should include the frequency of the related blocks.
- uint64_t NonLocalCost = 0;
- /// Frequency of the block where the local instructions live.
- uint64_t LocalFreq;
- MappingCost(uint64_t LocalCost, uint64_t NonLocalCost, uint64_t LocalFreq)
- : LocalCost(LocalCost), NonLocalCost(NonLocalCost),
- LocalFreq(LocalFreq) {}
- /// Check if this cost is saturated.
- bool isSaturated() const;
- public:
- /// Create a MappingCost assuming that most of the instructions
- /// will occur in a basic block with \p LocalFreq frequency.
- MappingCost(const BlockFrequency &LocalFreq);
- /// Add \p Cost to the local cost.
- /// \return true if this cost is saturated, false otherwise.
- bool addLocalCost(uint64_t Cost);
- /// Add \p Cost to the non-local cost.
- /// Non-local cost should reflect the frequency of their placement.
- /// \return true if this cost is saturated, false otherwise.
- bool addNonLocalCost(uint64_t Cost);
- /// Saturate the cost to the maximal representable value.
- void saturate();
- /// Return an instance of MappingCost that represents an
- /// impossible mapping.
- static MappingCost ImpossibleCost();
- /// Check if this is less than \p Cost.
- bool operator<(const MappingCost &Cost) const;
- /// Check if this is equal to \p Cost.
- bool operator==(const MappingCost &Cost) const;
- /// Check if this is not equal to \p Cost.
- bool operator!=(const MappingCost &Cost) const { return !(*this == Cost); }
- /// Check if this is greater than \p Cost.
- bool operator>(const MappingCost &Cost) const {
- return *this != Cost && Cost < *this;
- }
- /// Print this on dbgs() stream.
- void dump() const;
- /// Print this on \p OS;
- void print(raw_ostream &OS) const;
- /// Overload the stream operator for easy debug printing.
- friend raw_ostream &operator<<(raw_ostream &OS, const MappingCost &Cost) {
- Cost.print(OS);
- return OS;
- }
- };
- /// Interface to the target lowering info related
- /// to register banks.
- const RegisterBankInfo *RBI = nullptr;
- /// MRI contains all the register class/bank information that this
- /// pass uses and updates.
- MachineRegisterInfo *MRI = nullptr;
- /// Information on the register classes for the current function.
- const TargetRegisterInfo *TRI = nullptr;
- /// Get the frequency of blocks.
- /// This is required for non-fast mode.
- MachineBlockFrequencyInfo *MBFI = nullptr;
- /// Get the frequency of the edges.
- /// This is required for non-fast mode.
- MachineBranchProbabilityInfo *MBPI = nullptr;
- /// Current optimization remark emitter. Used to report failures.
- std::unique_ptr<MachineOptimizationRemarkEmitter> MORE;
- /// Helper class used for every code morphing.
- MachineIRBuilder MIRBuilder;
- /// Optimization mode of the pass.
- Mode OptMode;
- /// Current target configuration. Controls how the pass handles errors.
- const TargetPassConfig *TPC;
- /// Assign the register bank of each operand of \p MI.
- /// \return True on success, false otherwise.
- bool assignInstr(MachineInstr &MI);
- /// Initialize the field members using \p MF.
- void init(MachineFunction &MF);
- /// Check if \p Reg is already assigned what is described by \p ValMapping.
- /// \p OnlyAssign == true means that \p Reg just needs to be assigned a
- /// register bank. I.e., no repairing is necessary to have the
- /// assignment match.
- bool assignmentMatch(Register Reg,
- const RegisterBankInfo::ValueMapping &ValMapping,
- bool &OnlyAssign) const;
- /// Insert repairing code for \p Reg as specified by \p ValMapping.
- /// The repairing placement is specified by \p RepairPt.
- /// \p NewVRegs contains all the registers required to remap \p Reg.
- /// In other words, the number of registers in NewVRegs must be equal
- /// to ValMapping.BreakDown.size().
- ///
- /// The transformation could be sketched as:
- /// \code
- /// ... = op Reg
- /// \endcode
- /// Becomes
- /// \code
- /// <NewRegs> = COPY or extract Reg
- /// ... = op Reg
- /// \endcode
- ///
- /// and
- /// \code
- /// Reg = op ...
- /// \endcode
- /// Becomes
- /// \code
- /// Reg = op ...
- /// Reg = COPY or build_sequence <NewRegs>
- /// \endcode
- ///
- /// \pre NewVRegs.size() == ValMapping.BreakDown.size()
- ///
- /// \note The caller is supposed to do the rewriting of op if need be.
- /// I.e., Reg = op ... => <NewRegs> = NewOp ...
- ///
- /// \return True if the repairing worked, false otherwise.
- bool repairReg(MachineOperand &MO,
- const RegisterBankInfo::ValueMapping &ValMapping,
- RegBankSelect::RepairingPlacement &RepairPt,
- const iterator_range<SmallVectorImpl<Register>::const_iterator>
- &NewVRegs);
- /// Return the cost of the instruction needed to map \p MO to \p ValMapping.
- /// The cost is free of basic block frequencies.
- /// \pre MO.isReg()
- /// \pre MO is assigned to a register bank.
- /// \pre ValMapping is a valid mapping for MO.
- uint64_t
- getRepairCost(const MachineOperand &MO,
- const RegisterBankInfo::ValueMapping &ValMapping) const;
- /// Find the best mapping for \p MI from \p PossibleMappings.
- /// \return a reference on the best mapping in \p PossibleMappings.
- const RegisterBankInfo::InstructionMapping &
- findBestMapping(MachineInstr &MI,
- RegisterBankInfo::InstructionMappings &PossibleMappings,
- SmallVectorImpl<RepairingPlacement> &RepairPts);
- /// Compute the cost of mapping \p MI with \p InstrMapping and
- /// compute the repairing placement for such mapping in \p
- /// RepairPts.
- /// \p BestCost is used to specify when the cost becomes too high
- /// and thus it is not worth computing the RepairPts. Moreover if
- /// \p BestCost == nullptr, the mapping cost is actually not
- /// computed.
- MappingCost
- computeMapping(MachineInstr &MI,
- const RegisterBankInfo::InstructionMapping &InstrMapping,
- SmallVectorImpl<RepairingPlacement> &RepairPts,
- const MappingCost *BestCost = nullptr);
- /// When \p RepairPt involves splitting to repair \p MO for the
- /// given \p ValMapping, try to change the way we repair such that
- /// the splitting is not required anymore.
- ///
- /// \pre \p RepairPt.hasSplit()
- /// \pre \p MO == MO.getParent()->getOperand(\p RepairPt.getOpIdx())
- /// \pre \p ValMapping is the mapping of \p MO for MO.getParent()
- /// that implied \p RepairPt.
- void tryAvoidingSplit(RegBankSelect::RepairingPlacement &RepairPt,
- const MachineOperand &MO,
- const RegisterBankInfo::ValueMapping &ValMapping) const;
- /// Apply \p Mapping to \p MI. \p RepairPts represents the different
- /// mapping action that need to happen for the mapping to be
- /// applied.
- /// \return True if the mapping was applied sucessfully, false otherwise.
- bool applyMapping(MachineInstr &MI,
- const RegisterBankInfo::InstructionMapping &InstrMapping,
- SmallVectorImpl<RepairingPlacement> &RepairPts);
- public:
- /// Create a RegBankSelect pass with the specified \p RunningMode.
- RegBankSelect(Mode RunningMode = Fast);
- StringRef getPassName() const override { return "RegBankSelect"; }
- void getAnalysisUsage(AnalysisUsage &AU) const override;
- MachineFunctionProperties getRequiredProperties() const override {
- return MachineFunctionProperties()
- .set(MachineFunctionProperties::Property::IsSSA)
- .set(MachineFunctionProperties::Property::Legalized);
- }
- MachineFunctionProperties getSetProperties() const override {
- return MachineFunctionProperties().set(
- MachineFunctionProperties::Property::RegBankSelected);
- }
- MachineFunctionProperties getClearedProperties() const override {
- return MachineFunctionProperties()
- .set(MachineFunctionProperties::Property::NoPHIs);
- }
- /// Walk through \p MF and assign a register bank to every virtual register
- /// that are still mapped to nothing.
- /// The target needs to provide a RegisterBankInfo and in particular
- /// override RegisterBankInfo::getInstrMapping.
- ///
- /// Simplified algo:
- /// \code
- /// RBI = MF.subtarget.getRegBankInfo()
- /// MIRBuilder.setMF(MF)
- /// for each bb in MF
- /// for each inst in bb
- /// MIRBuilder.setInstr(inst)
- /// MappingCosts = RBI.getMapping(inst);
- /// Idx = findIdxOfMinCost(MappingCosts)
- /// CurRegBank = MappingCosts[Idx].RegBank
- /// MRI.setRegBank(inst.getOperand(0).getReg(), CurRegBank)
- /// for each argument in inst
- /// if (CurRegBank != argument.RegBank)
- /// ArgReg = argument.getReg()
- /// Tmp = MRI.createNewVirtual(MRI.getSize(ArgReg), CurRegBank)
- /// MIRBuilder.buildInstr(COPY, Tmp, ArgReg)
- /// inst.getOperand(argument.getOperandNo()).setReg(Tmp)
- /// \endcode
- bool runOnMachineFunction(MachineFunction &MF) override;
- };
- } // end namespace llvm
- #endif // LLVM_CODEGEN_GLOBALISEL_REGBANKSELECT_H
- #ifdef __GNUC__
- #pragma GCC diagnostic pop
- #endif
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