This file implements the targeting of the InstructionSelector class for AArch64. More...

#include "AArch64GlobalISelUtils.h"
#include "AArch64InstrInfo.h"
#include "AArch64MachineFunctionInfo.h"
#include "AArch64RegisterBankInfo.h"
#include "AArch64RegisterInfo.h"
#include "AArch64Subtarget.h"
#include "AArch64TargetMachine.h"
#include "MCTargetDesc/AArch64AddressingModes.h"
#include "MCTargetDesc/AArch64MCTargetDesc.h"
#include "llvm/BinaryFormat/Dwarf.h"
#include "llvm/CodeGen/GlobalISel/GIMatchTableExecutorImpl.h"
#include "llvm/CodeGen/GlobalISel/GenericMachineInstrs.h"
#include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
#include "llvm/CodeGen/GlobalISel/MIPatternMatch.h"
#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
#include "llvm/CodeGen/GlobalISel/Utils.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetOpcodes.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicsAArch64.h"
#include "llvm/IR/Type.h"
#include "llvm/Pass.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <optional>
#include "AArch64GenGlobalISel.inc"

Namespaces
namespace	llvm
	This is an optimization pass for GlobalISel generic memory operations.

Macros
#define	DEBUG_TYPE "aarch64-isel"

#define	GET_GLOBALISEL_PREDICATE_BITSET

#define	GET_GLOBALISEL_PREDICATES_DECL

#define	GET_GLOBALISEL_TEMPORARIES_DECL

#define	GET_GLOBALISEL_IMPL

#define	GET_GLOBALISEL_PREDICATES_INIT

#define	GET_GLOBALISEL_TEMPORARIES_INIT

Functions
static const TargetRegisterClass *	getMinClassForRegBank (const RegisterBank &RB, TypeSize SizeInBits, bool GetAllRegSet=false)
	Given a register bank, and size in bits, return the smallest register class that can represent that combination.

static bool	getSubRegForClass (const TargetRegisterClass *RC, const TargetRegisterInfo &TRI, unsigned &SubReg)
	Returns the correct subregister to use for a given register class.

static unsigned	getMinSizeForRegBank (const RegisterBank &RB)
	Returns the minimum size the given register bank can hold.

static Register	createTuple (ArrayRef< Register > Regs, const unsigned RegClassIDs[], const unsigned SubRegs[], MachineIRBuilder &MIB)
	Create a REG_SEQUENCE instruction using the registers in `Regs`.

static Register	createDTuple (ArrayRef< Register > Regs, MachineIRBuilder &MIB)
	Create a tuple of D-registers using the registers in `Regs`.

static Register	createQTuple (ArrayRef< Register > Regs, MachineIRBuilder &MIB)
	Create a tuple of Q-registers using the registers in `Regs`.

static std::optional< uint64_t >	getImmedFromMO (const MachineOperand &Root)

static bool	unsupportedBinOp (const MachineInstr &I, const AArch64RegisterBankInfo &RBI, const MachineRegisterInfo &MRI, const AArch64RegisterInfo &TRI)
	Check whether `I` is a currently unsupported binary operation:

static unsigned	selectBinaryOp (unsigned GenericOpc, unsigned RegBankID, unsigned OpSize)
	Select the AArch64 opcode for the basic binary operation `GenericOpc` (such as G_OR or G_SDIV), appropriate for the register bank `RegBankID` and of size `OpSize`.

static unsigned	selectLoadStoreUIOp (unsigned GenericOpc, unsigned RegBankID, unsigned OpSize)
	Select the AArch64 opcode for the G_LOAD or G_STORE operation `GenericOpc`, appropriate for the (value) register bank `RegBankID` and of memory access size `OpSize`.

static bool	copySubReg (MachineInstr &I, MachineRegisterInfo &MRI, const RegisterBankInfo &RBI, Register SrcReg, const TargetRegisterClass *To, unsigned SubReg)
	Helper function for selectCopy.

static std::pair< const TargetRegisterClass , const TargetRegisterClass >	getRegClassesForCopy (MachineInstr &I, const TargetInstrInfo &TII, MachineRegisterInfo &MRI, const TargetRegisterInfo &TRI, const RegisterBankInfo &RBI)
	Helper function to get the source and destination register classes for a copy.

static bool	selectDebugInstr (MachineInstr &I, MachineRegisterInfo &MRI, const RegisterBankInfo &RBI)

static bool	selectCopy (MachineInstr &I, const TargetInstrInfo &TII, MachineRegisterInfo &MRI, const TargetRegisterInfo &TRI, const RegisterBankInfo &RBI)

static unsigned	selectFPConvOpc (unsigned GenericOpc, LLT DstTy, LLT SrcTy)

static AArch64CC::CondCode	changeICMPPredToAArch64CC (CmpInst::Predicate P)

static void	changeFPCCToORAArch64CC (CmpInst::Predicate CC, AArch64CC::CondCode &CondCode, AArch64CC::CondCode &CondCode2)
	changeFPCCToORAArch64CC - Convert an IR fp condition code to an AArch64 CC.

static void	changeFPCCToANDAArch64CC (CmpInst::Predicate CC, AArch64CC::CondCode &CondCode, AArch64CC::CondCode &CondCode2)
	Convert an IR fp condition code to an AArch64 CC.

static Register	getTestBitReg (Register Reg, uint64_t &Bit, bool &Invert, MachineRegisterInfo &MRI)
	Return a register which can be used as a bit to test in a TB(N)Z.

static std::optional< int64_t >	getVectorShiftImm (Register Reg, MachineRegisterInfo &MRI)
	Returns the element immediate value of a vector shift operand if found.

static std::optional< int64_t >	getVectorSHLImm (LLT SrcTy, Register Reg, MachineRegisterInfo &MRI)
	Matches and returns the shift immediate value for a SHL instruction given a shift operand.

static bool	getLaneCopyOpcode (unsigned &CopyOpc, unsigned &ExtractSubReg, const unsigned EltSize)

static std::pair< unsigned, unsigned >	getInsertVecEltOpInfo (const RegisterBank &RB, unsigned EltSize)
	Return an <Opcode, SubregIndex> pair to do an vector elt insert of a given size and RB.

static bool	canEmitConjunction (Register Val, bool &CanNegate, bool &MustBeFirst, bool WillNegate, MachineRegisterInfo &MRI, unsigned Depth=0)
	Returns true if `Val` is a tree of AND/OR/CMP operations that can be expressed as a conjunction.

static bool	isSignExtendShiftType (AArch64_AM::ShiftExtendType Type)

static AArch64_AM::ShiftExtendType	getShiftTypeForInst (MachineInstr &MI)
	Given a shift instruction, return the correct shift type for that instruction.

static void	fixupPHIOpBanks (MachineInstr &MI, MachineRegisterInfo &MRI, const AArch64RegisterBankInfo &RBI)

InstructionSelector *	llvm::createAArch64InstructionSelector (const AArch64TargetMachine &, const AArch64Subtarget &, const AArch64RegisterBankInfo &)

Detailed Description

This file implements the targeting of the InstructionSelector class for AArch64.

Todo:: This should be generated by TableGen.

Definition in file AArch64InstructionSelector.cpp.

Macro Definition Documentation

◆ DEBUG_TYPE

#define DEBUG_TYPE "aarch64-isel"

Definition at line 51 of file AArch64InstructionSelector.cpp.

◆ GET_GLOBALISEL_IMPL

#define GET_GLOBALISEL_IMPL

Definition at line 546 of file AArch64InstructionSelector.cpp.

◆ GET_GLOBALISEL_PREDICATE_BITSET

#define GET_GLOBALISEL_PREDICATE_BITSET

Definition at line 64 of file AArch64InstructionSelector.cpp.

◆ GET_GLOBALISEL_PREDICATES_DECL

#define GET_GLOBALISEL_PREDICATES_DECL

Definition at line 533 of file AArch64InstructionSelector.cpp.

◆ GET_GLOBALISEL_PREDICATES_INIT

#define GET_GLOBALISEL_PREDICATES_INIT

◆ GET_GLOBALISEL_TEMPORARIES_DECL

#define GET_GLOBALISEL_TEMPORARIES_DECL

Definition at line 539 of file AArch64InstructionSelector.cpp.

◆ GET_GLOBALISEL_TEMPORARIES_INIT

#define GET_GLOBALISEL_TEMPORARIES_INIT

Function Documentation

◆ canEmitConjunction()

static bool canEmitConjunction	(	Register	Val,
		bool &	CanNegate,
		bool &	MustBeFirst,
		bool	WillNegate,
		MachineRegisterInfo &	MRI,
		unsigned	Depth = `0`
	)

static

Returns true if Val is a tree of AND/OR/CMP operations that can be expressed as a conjunction.

Parameters

CanNegate	Set to true if we can negate the whole sub-tree just by changing the conditions on the CMP tests. (this means we can call emitConjunctionRec() with Negate==true on this sub-tree)
MustBeFirst	Set to true if this subtree needs to be negated and we cannot do the negation naturally. We are required to emit the subtree first in this case.
WillNegate	Is true if are called when the result of this subexpression must be negated. This happens when the outer expression is an OR. We can use this fact to know that we have a double negation (or (or ...) ...) that can be implemented for free.

Definition at line 4805 of file AArch64InstructionSelector.cpp.

References assert(), canEmitConjunction(), llvm::Depth, llvm::MachineInstr::getOpcode(), llvm::MachineInstr::getOperand(), llvm::MachineOperand::getReg(), and MRI.

Referenced by canEmitConjunction().

◆ changeFPCCToANDAArch64CC()

static void changeFPCCToANDAArch64CC	(	CmpInst::Predicate	CC,
		AArch64CC::CondCode &	CondCode,
		AArch64CC::CondCode &	CondCode2
	)

static

Convert an IR fp condition code to an AArch64 CC.

This differs from changeFPCCToAArch64CC in that it returns cond codes that should be AND'ed instead of OR'ed.

Definition at line 1436 of file AArch64InstructionSelector.cpp.

References llvm::AArch64CC::AL, assert(), CC, changeFPCCToORAArch64CC(), llvm::CmpInst::FCMP_ONE, llvm::CmpInst::FCMP_UEQ, llvm::AArch64CC::LE, llvm::AArch64CC::NE, llvm::AArch64CC::PL, and llvm::AArch64CC::VC.

◆ changeFPCCToORAArch64CC()

static void changeFPCCToORAArch64CC	(	CmpInst::Predicate	CC,
		AArch64CC::CondCode &	CondCode,
		AArch64CC::CondCode &	CondCode2
	)

static

changeFPCCToORAArch64CC - Convert an IR fp condition code to an AArch64 CC.

Definition at line 1379 of file AArch64InstructionSelector.cpp.

Referenced by changeFPCCToANDAArch64CC().

◆ changeICMPPredToAArch64CC()

static AArch64CC::CondCode changeICMPPredToAArch64CC ( CmpInst::Predicate P )

static

◆ copySubReg()

static bool copySubReg	(	MachineInstr &	I,
		MachineRegisterInfo &	MRI,
		const RegisterBankInfo &	RBI,
		Register	SrcReg,
		const TargetRegisterClass *	To,
		unsigned	SubReg
	)

static

Helper function for selectCopy.

Inserts a subregister copy from SrcReg to *To.

E.g "To = COPY SrcReg:SubReg"

Definition at line 928 of file AArch64InstructionSelector.cpp.

References assert(), llvm::MachineIRBuilder::buildInstr(), llvm::RegisterBankInfo::constrainGenericRegister(), I, llvm::Register::isValid(), MRI, llvm::MachineOperand::setReg(), and SubReg.

Referenced by selectCopy().

◆ createDTuple()

static Register createDTuple	(	ArrayRef< Register >	Regs,
		MachineIRBuilder &	MIB
	)

static

Create a tuple of D-registers using the registers in Regs.

Definition at line 729 of file AArch64InstructionSelector.cpp.

References createTuple().

◆ createQTuple()

static Register createQTuple	(	ArrayRef< Register >	Regs,
		MachineIRBuilder &	MIB
	)

static

Create a tuple of Q-registers using the registers in Regs.

Definition at line 738 of file AArch64InstructionSelector.cpp.

References createTuple().

◆ createTuple()

static Register createTuple	(	ArrayRef< Register >	Regs,
		const unsigned	RegClassIDs[],
		const unsigned	SubRegs[],
		MachineIRBuilder &	MIB
	)

static

Create a REG_SEQUENCE instruction using the registers in Regs.

Helper function for functions like createDTuple and createQTuple.

RegClassIDs - The list of register class IDs available for some tuple of a scalar class. E.g. QQRegClassID, QQQRegClassID, QQQQRegClassID. This is expected to contain between 2 and 4 tuple classes.

SubRegs - The list of subregister classes associated with each register class ID in RegClassIDs. E.g., QQRegClassID should use the qsub0 subregister class. The index of each subregister class is expected to correspond with the index of each register class.

Returns: Either the destination register of REG_SEQUENCE instruction that was created, or the 0th element of Regs if Regs contains a single element.

Definition at line 709 of file AArch64InstructionSelector.cpp.

References assert(), llvm::MachineIRBuilder::buildInstr(), llvm::MachineIRBuilder::getMF(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), I, llvm::ArrayRef< T >::size(), and TRI.

Referenced by createDTuple(), and createQTuple().

◆ fixupPHIOpBanks()

static void fixupPHIOpBanks	(	MachineInstr &	MI,
		MachineRegisterInfo &	MRI,
		const AArch64RegisterBankInfo &	RBI
	)

static

Definition at line 7998 of file AArch64InstructionSelector.cpp.

References assert(), llvm::MachineIRBuilder::buildCopy(), llvm::drop_begin(), llvm::MachineBasicBlock::end(), llvm::MachineBasicBlock::getFirstNonPHI(), llvm::MachineBasicBlock::getParent(), MI, MRI, and llvm::MachineIRBuilder::setInsertPt().

◆ getImmedFromMO()

static std::optional< uint64_t > getImmedFromMO ( const MachineOperand & Root )

static

Definition at line 746 of file AArch64InstructionSelector.cpp.

References llvm::MachineOperand::getCImm(), llvm::getIConstantVRegValWithLookThrough(), llvm::MachineOperand::getImm(), llvm::MachineOperand::getParent(), llvm::MachineBasicBlock::getParent(), llvm::MachineOperand::getReg(), llvm::ConstantInt::getZExtValue(), llvm::MachineOperand::isCImm(), llvm::MachineOperand::isImm(), llvm::MachineOperand::isReg(), MBB, MI, and MRI.

◆ getInsertVecEltOpInfo()

static std::pair< unsigned, unsigned > getInsertVecEltOpInfo	(	const RegisterBank &	RB,
		unsigned	EltSize
	)

static

Return an <Opcode, SubregIndex> pair to do an vector elt insert of a given size and RB.

Definition at line 4336 of file AArch64InstructionSelector.cpp.

References llvm::RegisterBank::getID(), and llvm_unreachable.

◆ getLaneCopyOpcode()

static bool getLaneCopyOpcode	(	unsigned &	CopyOpc,
		unsigned &	ExtractSubReg,
		const unsigned	EltSize
	)

static

Definition at line 3978 of file AArch64InstructionSelector.cpp.

References llvm::dbgs(), and LLVM_DEBUG.

◆ getMinClassForRegBank()

static const TargetRegisterClass * getMinClassForRegBank	(	const RegisterBank &	RB,
		TypeSize	SizeInBits,
		bool	GetAllRegSet = `false`
	)

static

Given a register bank, and size in bits, return the smallest register class that can represent that combination.

Definition at line 606 of file AArch64InstructionSelector.cpp.

References assert(), llvm::RegisterBank::getID(), llvm::TypeSize::getScalable(), and llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::isScalable().

Referenced by getRegClassesForCopy(), and selectCopy().

◆ getMinSizeForRegBank()

static unsigned getMinSizeForRegBank ( const RegisterBank & RB )

static

Returns the minimum size the given register bank can hold.

Definition at line 683 of file AArch64InstructionSelector.cpp.

References llvm::RegisterBank::getID(), and llvm_unreachable.

Referenced by selectCopy().

◆ getRegClassesForCopy()

static std::pair< const TargetRegisterClass , const TargetRegisterClass > getRegClassesForCopy	(	MachineInstr &	I,
		const TargetInstrInfo &	TII,
		MachineRegisterInfo &	MRI,
		const TargetRegisterInfo &	TRI,
		const RegisterBankInfo &	RBI
	)

static

Helper function to get the source and destination register classes for a copy.

Returns a std::pair containing the source register class for the copy, and the destination register class for the copy. If a register class cannot be determined, then it will be nullptr.

Definition at line 954 of file AArch64InstructionSelector.cpp.

References llvm::TypeSize::getFixed(), getMinClassForRegBank(), llvm::RegisterBankInfo::getRegBank(), llvm::RegisterBankInfo::getSizeInBits(), I, MRI, and TRI.

Referenced by selectCopy().

◆ getShiftTypeForInst()

static AArch64_AM::ShiftExtendType getShiftTypeForInst ( MachineInstr & MI )

static

Given a shift instruction, return the correct shift type for that instruction.

Definition at line 7657 of file AArch64InstructionSelector.cpp.

References llvm::AArch64_AM::ASR, llvm::AArch64_AM::InvalidShiftExtend, llvm::AArch64_AM::LSL, llvm::AArch64_AM::LSR, MI, and llvm::AArch64_AM::ROR.

◆ getSubRegForClass()

static bool getSubRegForClass	(	const TargetRegisterClass *	RC,
		const TargetRegisterInfo &	TRI,
		unsigned &	SubReg
	)

static

Returns the correct subregister to use for a given register class.

Definition at line 655 of file AArch64InstructionSelector.cpp.

References llvm::dbgs(), LLVM_DEBUG, SubReg, and TRI.

Referenced by selectCopy().

◆ getTestBitReg()

static Register getTestBitReg	(	Register	Reg,
		uint64_t &	Bit,
		bool &	Invert,
		MachineRegisterInfo &	MRI
	)

static

Return a register which can be used as a bit to test in a TB(N)Z.

Definition at line 1463 of file AArch64InstructionSelector.cpp.

References assert(), llvm::CallingConv::C, llvm::getDefIgnoringCopies(), llvm::getIConstantVRegValWithLookThrough(), llvm::Register::isValid(), MI, MRI, and std::swap().

◆ getVectorShiftImm()

static std::optional< int64_t > getVectorShiftImm	(	Register	Reg,
		MachineRegisterInfo &	MRI
	)

static

Returns the element immediate value of a vector shift operand if found.

This needs to detect a splat-like operation, e.g. a G_BUILD_VECTOR.

Definition at line 1856 of file AArch64InstructionSelector.cpp.

References assert(), llvm::AArch64GISelUtils::getAArch64VectorSplatScalar(), and MRI.

Referenced by getVectorSHLImm().

◆ getVectorSHLImm()

static std::optional< int64_t > getVectorSHLImm	(	LLT	SrcTy,
		Register	Reg,
		MachineRegisterInfo &	MRI
	)

static

Matches and returns the shift immediate value for a SHL instruction given a shift operand.

Definition at line 1865 of file AArch64InstructionSelector.cpp.

References llvm::dbgs(), llvm::LLT::getElementType(), llvm::LLT::getSizeInBits(), getVectorShiftImm(), LLVM_DEBUG, and MRI.

◆ isSignExtendShiftType()

static bool isSignExtendShiftType ( AArch64_AM::ShiftExtendType Type )

static

Definition at line 7184 of file AArch64InstructionSelector.cpp.

References llvm::AArch64_AM::SXTB, llvm::AArch64_AM::SXTH, and llvm::AArch64_AM::SXTW.

◆ selectBinaryOp()

static unsigned selectBinaryOp	(	unsigned	GenericOpc,
		unsigned	RegBankID,
		unsigned	OpSize
	)

static

Select the AArch64 opcode for the basic binary operation GenericOpc (such as G_OR or G_SDIV), appropriate for the register bank RegBankID and of size OpSize.

Returns: GenericOpc if the combination is unsupported.

Definition at line 819 of file AArch64InstructionSelector.cpp.

◆ selectCopy()

static bool selectCopy	(	MachineInstr &	I,
		const TargetInstrInfo &	TII,
		MachineRegisterInfo &	MRI,
		const TargetRegisterInfo &	TRI,
		const RegisterBankInfo &	RBI
	)

static

◆ selectDebugInstr()

static bool selectDebugInstr	(	MachineInstr &	I,
		MachineRegisterInfo &	MRI,
		const RegisterBankInfo &	RBI
	)

static

Definition at line 984 of file AArch64InstructionSelector.cpp.

References llvm::RegisterBankInfo::constrainGenericRegister(), llvm::dbgs(), I, LLVM_DEBUG, and MRI.

◆ selectFPConvOpc()

static unsigned selectFPConvOpc	(	unsigned	GenericOpc,
		LLT	DstTy,
		LLT	SrcTy
	)

static

Definition at line 1104 of file AArch64InstructionSelector.cpp.

References llvm::LLT::getSizeInBits(), and llvm::LLT::isScalar().

◆ selectLoadStoreUIOp()

static unsigned selectLoadStoreUIOp	(	unsigned	GenericOpc,
		unsigned	RegBankID,
		unsigned	OpSize
	)

static

Select the AArch64 opcode for the G_LOAD or G_STORE operation GenericOpc, appropriate for the (value) register bank RegBankID and of memory access size OpSize.

This returns the variant with the base+unsigned-immediate addressing mode (e.g., LDRXui).

Returns: GenericOpc if the combination is unsupported.

Definition at line 890 of file AArch64InstructionSelector.cpp.

References isStore().

◆ unsupportedBinOp()

static bool unsupportedBinOp	(	const MachineInstr &	I,
		const AArch64RegisterBankInfo &	RBI,
		const MachineRegisterInfo &	MRI,
		const AArch64RegisterInfo &	TRI
	)

static

Check whether I is a currently unsupported binary operation:

it has an unsized type
an operand is not a vreg
all operands are not in the same bank These are checks that should someday live in the verifier, but right now, these are mostly limitations of the aarch64 selector.

Definition at line 773 of file AArch64InstructionSelector.cpp.

References llvm::dbgs(), llvm::RegisterBankInfo::getRegBank(), I, llvm::LLT::isValid(), LLVM_DEBUG, MRI, and TRI.

Namespaces

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ DEBUG_TYPE

◆ GET_GLOBALISEL_IMPL

◆ GET_GLOBALISEL_PREDICATE_BITSET

◆ GET_GLOBALISEL_PREDICATES_DECL

◆ GET_GLOBALISEL_PREDICATES_INIT

◆ GET_GLOBALISEL_TEMPORARIES_DECL

◆ GET_GLOBALISEL_TEMPORARIES_INIT

Function Documentation

◆ canEmitConjunction()

◆ changeFPCCToANDAArch64CC()

◆ changeFPCCToORAArch64CC()

◆ changeICMPPredToAArch64CC()

◆ copySubReg()

◆ createDTuple()

◆ createQTuple()

◆ createTuple()

◆ fixupPHIOpBanks()

◆ getImmedFromMO()

◆ getInsertVecEltOpInfo()

◆ getLaneCopyOpcode()

◆ getMinClassForRegBank()

◆ getMinSizeForRegBank()

◆ getRegClassesForCopy()

◆ getShiftTypeForInst()

◆ getSubRegForClass()

◆ getTestBitReg()

◆ getVectorShiftImm()

◆ getVectorSHLImm()

◆ isSignExtendShiftType()

◆ selectBinaryOp()

◆ selectCopy()

◆ selectDebugInstr()

◆ selectFPConvOpc()

◆ selectLoadStoreUIOp()

◆ unsupportedBinOp()