llvm::VFABI Namespace Reference

Functions
std::optional< VFInfo >	tryDemangleForVFABI (StringRef MangledName, const Module &M)
	Function to construct a VFInfo out of a mangled names in the following format:
std::string	mangleTLIVectorName (StringRef VectorName, StringRef ScalarName, unsigned numArgs, ElementCount VF, bool Masked=false)
	This routine mangles the given VectorName according to the LangRef specification for vector-function-abi-variant attribute and is specific to the TLI mappings.
VFParamKind	getVFParamKindFromString (const StringRef Token)
	Retrieve the VFParamKind from a string token.
void	getVectorVariantNames (const CallInst &CI, SmallVectorImpl< std::string > &VariantMappings)
	Populates a set of strings representing the Vector Function ABI variants associated to the CallInst CI.
void	setVectorVariantNames (CallInst *CI, ArrayRef< std::string > VariantMappings)
	Overwrite the Vector Function ABI variants attribute with the names provide in VariantMappings.

Variables
static constexpr char const *	_LLVM_ = "_LLVM_"
	LLVM Internal VFABI ISA token for vector functions.
static constexpr char const *	_LLVM_Scalarize_ = "_LLVM_Scalarize_"
	Prefix for internal name redirection for vector function that tells the compiler to scalarize the call using the scalar name of the function.
static constexpr char const *	MappingsAttrName = "vector-function-abi-variant"

Function Documentation

getVectorVariantNames()

void llvm::VFABI::getVectorVariantNames	(	const CallInst &	CI,
		SmallVectorImpl< std::string > &	VariantMappings
	)

Populates a set of strings representing the Vector Function ABI variants associated to the CallInst CI.

If the CI does not contain the vector-function-abi-variant attribute, we return without populating VariantMappings, i.e. callers of getVectorVariantNames need not check for the presence of the attribute (see InjectTLIMappings).

Definition at line 1416 of file VectorUtils.cpp.

References assert(), llvm::SmallVectorTemplateCommon< T, typename >::begin(), llvm::dbgs(), llvm::StringRef::empty(), llvm::SmallVectorTemplateCommon< T, typename >::end(), llvm::CallBase::getFnAttr(), llvm::Module::getFunction(), llvm::Instruction::getModule(), llvm::Attribute::getValueAsString(), Info, LLVM_DEBUG, MappingsAttrName, llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::StringRef::split(), and tryDemangleForVFABI().

Referenced by addMappingsFromTLI().

getVFParamKindFromString()

VFParamKind llvm::VFABI::getVFParamKindFromString

(

const StringRef

Token

)

Retrieve the VFParamKind from a string token.

Definition at line 458 of file VFABIDemangling.cpp.

References llvm::StringSwitch< T, R >::Case(), llvm::StringSwitch< T, R >::Default(), and llvm_unreachable.

mangleTLIVectorName()

std::string llvm::VFABI::mangleTLIVectorName	(	StringRef	VectorName,
		StringRef	ScalarName,
		unsigned	numArgs,
		ElementCount	VF,
		bool	Masked = false
	)

This routine mangles the given VectorName according to the LangRef specification for vector-function-abi-variant attribute and is specific to the TLI mappings.

It is the responsibility of the caller to make sure that this is only used if all parameters in the vector function are vector type. This returned string holds scalar-to-vector mapping: ZGV<isa><mask><vlen><vparams><scalarname>(<vectorname>)

where:

<isa> = "_LLVM_" <mask> = "M" if masked, "N" if no mask. <vlen> = Number of concurrent lanes, stored in the VectorizationFactor field of the VecDesc struct. If the number of lanes is scalable then 'x' is printed instead. <vparams> = "v", as many as are the numArgs. <scalarname> = the name of the scalar function. <vectorname> = the name of the vector function.

Definition at line 1400 of file VectorUtils.cpp.

References _LLVM_, llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::getFixedValue(), I, llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::isScalable(), and llvm::raw_svector_ostream::str().

Referenced by addMappingsFromTLI().

setVectorVariantNames()

void llvm::VFABI::setVectorVariantNames	(	CallInst *	CI,
		ArrayRef< std::string >	VariantMappings
	)

Overwrite the Vector Function ABI variants attribute with the names provide in VariantMappings.

Definition at line 330 of file ModuleUtils.cpp.

References llvm::CallBase::addFnAttr(), assert(), llvm::dbgs(), llvm::ArrayRef< T >::empty(), llvm::StringRef::empty(), llvm::Attribute::get(), llvm::Instruction::getModule(), LLVM_DEBUG, llvm::SmallVectorTemplateBase< T, bool >::pop_back(), llvm::SmallString< InternalLen >::str(), tryDemangleForVFABI(), and VI.

Referenced by addMappingsFromTLI().

tryDemangleForVFABI()

std::optional< VFInfo > llvm::VFABI::tryDemangleForVFABI	(	StringRef	MangledName,
		const Module &	M
	)

Function to construct a VFInfo out of a mangled names in the following format:

<VFABI_name>{(<redirection>)}

where <VFABI_name> is the name of the vector function, mangled according to the rules described in the Vector Function ABI of the target vector extension (or <isa> from now on). The <VFABI_name> is in the following format:

ZGV<isa><mask><vlen><parameters><scalarname>[(<redirection>)]

This methods support demangling rules for the following <isa>:

• AArch64: https://developer.arm.com/docs/101129/latest
• x86 (libmvec): https://sourceware.org/glibc/wiki/libmvec and https://sourceware.org/glibc/wiki/libmvec?action=AttachFile&do=view&target=VectorABI.txt

Parameters

MangledName	-> input string in the format ZGV<isa><mask><vlen><parameters><scalarname>[(<redirection>)].
M	-> Module used to retrieve informations about the vector function that are not possible to retrieve from the mangled name. At the moment, this parameter is needed only to retrieve the Vectorization Factor of scalable vector functions from their respective IR declarations.

Definition at line 317 of file VFABIDemangling.cpp.

References assert(), llvm::SmallVectorTemplateCommon< T, typename >::back(), llvm::StringRef::consume_back(), llvm::StringRef::consume_front(), llvm::count_if(), llvm::SmallVectorBase< Size_T >::empty(), llvm::StringRef::empty(), F, llvm::ElementCount::get(), llvm::StringRef::ltrim(), llvm::VFParameter::ParamKind, llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::SmallVectorBase< Size_T >::size(), and llvm::StringRef::take_while().

Referenced by getVectorVariantNames(), and setVectorVariantNames().

Variable Documentation

_LLVM_

constexpr char const* llvm::VFABI::_LLVM_ = "_LLVM_"

staticconstexpr

LLVM Internal VFABI ISA token for vector functions.

Definition at line 147 of file VectorUtils.h.

Referenced by mangleTLIVectorName().

_LLVM_Scalarize_

constexpr char const* llvm::VFABI::_LLVM_Scalarize_ = "_LLVM_Scalarize_"

staticconstexpr

Prefix for internal name redirection for vector function that tells the compiler to scalarize the call using the scalar name of the function.

For example, a mangled name like _ZGV_LLVM_N2v_foo(_LLVM_Scalarize_foo) would tell the vectorizer to vectorize the scalar call foo, and to scalarize it once vectorization is done.

Definition at line 154 of file VectorUtils.h.

MappingsAttrName

constexpr char const* llvm::VFABI::MappingsAttrName = "vector-function-abi-variant"

staticconstexpr

Definition at line 210 of file VectorUtils.h.

Referenced by getVectorVariantNames().