CombinerHelper.cpp File Reference (original) (raw)

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Functions
static unsigned	littleEndianByteAt (const unsigned ByteWidth, const unsigned I)

static Register	buildLogBase2 (Register V, MachineIRBuilder &MIB)
	Determines the LogBase2 value for a non-null input value using the transform: LogBase2(V) = (EltBits - 1) - ctlz(V).

static unsigned	bigEndianByteAt (const unsigned ByteWidth, const unsigned I)

static std::optional< bool >	isBigEndian (const SmallDenseMap< int64_t, int64_t, 8 > &MemOffset2Idx, int64_t LowestIdx)
	Given a map from byte offsets in memory to indices in a load/store, determine if that map corresponds to a little or big endian byte pattern.

static unsigned	getExtLoadOpcForExtend (unsigned ExtOpc)

static bool	canFoldInAddressingMode (GLoadStore *MI, const TargetLowering &TLI, MachineRegisterInfo &MRI)
	Return true if 'MI' is a load or a store that may be fold it's address operand into the load / store addressing mode.

static unsigned	getIndexedOpc (unsigned LdStOpc)

static APFloat	constantFoldFpUnary (const MachineInstr &MI, const MachineRegisterInfo &MRI, const APFloat &Val)

static Register	peekThroughBitcast (Register Reg, const MachineRegisterInfo &MRI)

static LLT	getMidVTForTruncRightShiftCombine (LLT ShiftTy, LLT TruncTy)

static bool	isConstValidTrue (const TargetLowering &TLI, unsigned ScalarSizeBits, int64_t Cst, bool IsVector, bool IsFP)

static std::optional< std::pair< GZExtLoad *, int64_t > >	matchLoadAndBytePosition (Register Reg, unsigned MemSizeInBits, const MachineRegisterInfo &MRI)
	Helper function for findLoadOffsetsForLoadOrCombine.

static bool	isContractableFMul (MachineInstr &MI, bool AllowFusionGlobally)
	Checks if MI is TargetOpcode::G_FMUL and contractable either due to global flags or MachineInstr flags.

static bool	hasMoreUses (const MachineInstr &MI0, const MachineInstr &MI1, const MachineRegisterInfo &MRI)

static std::optional< unsigned >	getMinUselessShift (KnownBits ValueKB, unsigned Opcode, std::optional< int64_t > &Result)
	Return the minimum useless shift amount that results in complete loss of the source value.

static void	commuteMask (MutableArrayRef< int > Mask, const unsigned NumElems)

◆ DEBUG_TYPE

#define DEBUG_TYPE "gi-combiner"

◆ bigEndianByteAt()

◆ buildLogBase2()

◆ canFoldInAddressingMode()

◆ commuteMask()

◆ constantFoldFpUnary()

◆ getExtLoadOpcForExtend()

◆ getIndexedOpc()

◆ getMidVTForTruncRightShiftCombine()

static LLT getMidVTForTruncRightShiftCombine ( LLT ShiftTy, LLT TruncTy )	static

◆ getMinUselessShift()

static std::optional< unsigned > getMinUselessShift ( KnownBits ValueKB, unsigned Opcode, std::optional< int64_t > & Result )	static

◆ hasMoreUses()

◆ isBigEndian()

static std::optional< bool > isBigEndian ( const SmallDenseMap< int64_t, int64_t, 8 > & MemOffset2Idx, int64_t LowestIdx )	static

Given a map from byte offsets in memory to indices in a load/store, determine if that map corresponds to a little or big endian byte pattern.

Parameters

MemOffset2Idx	maps memory offsets to address offsets.
LowestIdx	is the lowest index in MemOffset2Idx.

Returns

true if the map corresponds to a big endian byte pattern, false if it corresponds to a little endian byte pattern, and std::nullopt otherwise.

E.g. given a 32-bit type x, and x[AddrOffset], the in-memory byte patterns are as follows:

AddrOffset Little endian Big endian 0 0 3 1 1 2 2 2 1 3 3 0

Definition at line 127 of file CombinerHelper.cpp.

References assert(), bigEndianByteAt(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::find(), Idx, littleEndianByteAt(), and llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::size().

Referenced by collectInsertionElements(), createGPRPairNodei64(), llvm::SelectionDAG::getConstant(), llvm::CombinerHelper::matchLoadOrCombine(), PerformSTORECombine(), llvm::LegalizerHelper::reduceLoadStoreWidth(), ReplaceCMP_SWAP_64Results(), and llvm::orc::OrcMips32_Base::writeResolverCode().

◆ isConstValidTrue()

◆ isContractableFMul()

◆ littleEndianByteAt()

◆ matchLoadAndBytePosition()

◆ peekThroughBitcast()

◆ ForceLegalIndexing

cl::opt< bool > ForceLegalIndexing("force-legal-indexing", cl::Hidden, cl::init(false), cl::desc("Force all indexed operations to be " "legal for the GlobalISel combiner")) ( "force-legal-indexing" , cl::Hidden , cl::init(false) , cl::desc("Force all indexed operations to be " "legal for the GlobalISel combiner") )	static

◆ PostIndexUseThreshold

cl::opt< unsigned > PostIndexUseThreshold("post-index-use-threshold", cl::Hidden, cl::init(32), cl::desc("Number of uses of a base pointer to check before it is no longer " "considered for post-indexing.")) ( "post-index-use-threshold" , cl::Hidden , cl::init(32) , cl::desc("Number of uses of a base pointer to check before it is no longer " "considered for post-indexing.") )	static