//===-- TargetLibraryInfo.h - Library information ---------------*- 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
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_TARGETLIBRARYINFO_H
#define LLVM_ANALYSIS_TARGETLIBRARYINFO_H
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/Triple.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/PassManager.h"
#include "llvm/Pass.h"
#include <optional>
namespace llvm {
template <typename T> class ArrayRef;
class Function;
class Module;
class Triple;
/// Describes a possible vectorization of a function.
/// Function 'VectorFnName' is equivalent to 'ScalarFnName' vectorized
/// by a factor 'VectorizationFactor'.
struct VecDesc {
StringRef ScalarFnName;
StringRef VectorFnName;
ElementCount VectorizationFactor;
};
enum LibFunc : unsigned {
#define TLI_DEFINE_ENUM
#include "llvm/Analysis/TargetLibraryInfo.def"
NumLibFuncs,
NotLibFunc
};
/// Implementation of the target library information.
///
/// This class constructs tables that hold the target library information and
/// make it available. However, it is somewhat expensive to compute and only
/// depends on the triple. So users typically interact with the \c
/// TargetLibraryInfo wrapper below.
class TargetLibraryInfoImpl {
friend class TargetLibraryInfo;
unsigned char AvailableArray[(NumLibFuncs+3)/4];
DenseMap<unsigned, std::string> CustomNames;
static StringLiteral const StandardNames[NumLibFuncs];
bool ShouldExtI32Param, ShouldExtI32Return, ShouldSignExtI32Param, ShouldSignExtI32Return;
unsigned SizeOfInt;
enum AvailabilityState {
StandardName = 3, // (memset to all ones)
CustomName = 1,
Unavailable = 0 // (memset to all zeros)
};
void setState(LibFunc F, AvailabilityState State) {
AvailableArray[F/4] &= ~(3 << 2*(F&3));
AvailableArray[F/4] |= State << 2*(F&3);
}
AvailabilityState getState(LibFunc F) const {
return static_cast<AvailabilityState>((AvailableArray[F/4] >> 2*(F&3)) & 3);
}
/// Vectorization descriptors - sorted by ScalarFnName.
std::vector<VecDesc> VectorDescs;
/// Scalarization descriptors - same content as VectorDescs but sorted based
/// on VectorFnName rather than ScalarFnName.
std::vector<VecDesc> ScalarDescs;
/// Return true if the function type FTy is valid for the library function
/// F, regardless of whether the function is available.
bool isValidProtoForLibFunc(const FunctionType &FTy, LibFunc F,
const Module &M) const;
public:
/// List of known vector-functions libraries.
///
/// The vector-functions library defines, which functions are vectorizable
/// and with which factor. The library can be specified by either frontend,
/// or a commandline option, and then used by
/// addVectorizableFunctionsFromVecLib for filling up the tables of
/// vectorizable functions.
enum VectorLibrary {
NoLibrary, // Don't use any vector library.
Accelerate, // Use Accelerate framework.
DarwinLibSystemM, // Use Darwin's libsystem_m.
LIBMVEC_X86, // GLIBC Vector Math library.
MASSV, // IBM MASS vector library.
SVML, // Intel short vector math library.
SLEEFGNUABI // SLEEF - SIMD Library for Evaluating Elementary Functions.
};
TargetLibraryInfoImpl();
explicit TargetLibraryInfoImpl(const Triple &T);
// Provide value semantics.
TargetLibraryInfoImpl(const TargetLibraryInfoImpl &TLI);
TargetLibraryInfoImpl(TargetLibraryInfoImpl &&TLI);
TargetLibraryInfoImpl &operator=(const TargetLibraryInfoImpl &TLI);
TargetLibraryInfoImpl &operator=(TargetLibraryInfoImpl &&TLI);
/// Searches for a particular function name.
///
/// If it is one of the known library functions, return true and set F to the
/// corresponding value.
bool getLibFunc(StringRef funcName, LibFunc &F) const;
/// Searches for a particular function name, also checking that its type is
/// valid for the library function matching that name.
///
/// If it is one of the known library functions, return true and set F to the
/// corresponding value.
///
/// FDecl is assumed to have a parent Module when using this function.
bool getLibFunc(const Function &FDecl, LibFunc &F) const;
/// Forces a function to be marked as unavailable.
void setUnavailable(LibFunc F) {
setState(F, Unavailable);
}
/// Forces a function to be marked as available.
void setAvailable(LibFunc F) {
setState(F, StandardName);
}
/// Forces a function to be marked as available and provide an alternate name
/// that must be used.
void setAvailableWithName(LibFunc F, StringRef Name) {
if (StandardNames[F] != Name) {
setState(F, CustomName);
CustomNames[F] = std::string(Name);
assert(CustomNames.find(F) != CustomNames.end());
} else {
setState(F, StandardName);
}
}
/// Disables all builtins.
///
/// This can be used for options like -fno-builtin.
void disableAllFunctions();
/// Add a set of scalar -> vector mappings, queryable via
/// getVectorizedFunction and getScalarizedFunction.
void addVectorizableFunctions(ArrayRef<VecDesc> Fns);
/// Calls addVectorizableFunctions with a known preset of functions for the
/// given vector library.
void addVectorizableFunctionsFromVecLib(enum VectorLibrary VecLib,
const llvm::Triple &TargetTriple);
/// Return true if the function F has a vector equivalent with vectorization
/// factor VF.
bool isFunctionVectorizable(StringRef F, const ElementCount &VF) const {
return !getVectorizedFunction(F, VF).empty();
}
/// Return true if the function F has a vector equivalent with any
/// vectorization factor.
bool isFunctionVectorizable(StringRef F) const;
/// Return the name of the equivalent of F, vectorized with factor VF. If no
/// such mapping exists, return the empty string.
StringRef getVectorizedFunction(StringRef F, const ElementCount &VF) const;
/// Set to true iff i32 parameters to library functions should have signext
/// or zeroext attributes if they correspond to C-level int or unsigned int,
/// respectively.
void setShouldExtI32Param(bool Val) {
ShouldExtI32Param = Val;
}
/// Set to true iff i32 results from library functions should have signext
/// or zeroext attributes if they correspond to C-level int or unsigned int,
/// respectively.
void setShouldExtI32Return(bool Val) {
ShouldExtI32Return = Val;
}
/// Set to true iff i32 parameters to library functions should have signext
/// attribute if they correspond to C-level int or unsigned int.
void setShouldSignExtI32Param(bool Val) {
ShouldSignExtI32Param = Val;
}
/// Set to true iff i32 results from library functions should have signext
/// attribute if they correspond to C-level int or unsigned int.
void setShouldSignExtI32Return(bool Val) {
ShouldSignExtI32Return = Val;
}
/// Returns the size of the wchar_t type in bytes or 0 if the size is unknown.
/// This queries the 'wchar_size' metadata.
unsigned getWCharSize(const Module &M) const;
/// Returns the size of the size_t type in bits.
unsigned getSizeTSize(const Module &M) const;
/// Get size of a C-level int or unsigned int, in bits.
unsigned getIntSize() const {
return SizeOfInt;
}
/// Initialize the C-level size of an integer.
void setIntSize(unsigned Bits) {
SizeOfInt = Bits;
}
/// Returns the largest vectorization factor used in the list of
/// vector functions.
void getWidestVF(StringRef ScalarF, ElementCount &FixedVF,
ElementCount &Scalable) const;
/// Returns true if call site / callee has cdecl-compatible calling
/// conventions.
static bool isCallingConvCCompatible(CallBase *CI);
static bool isCallingConvCCompatible(Function *Callee);
};
/// Provides information about what library functions are available for
/// the current target.
///
/// This both allows optimizations to handle them specially and frontends to
/// disable such optimizations through -fno-builtin etc.
class TargetLibraryInfo {
friend class TargetLibraryAnalysis;
friend class TargetLibraryInfoWrapperPass;
/// The global (module level) TLI info.
const TargetLibraryInfoImpl *Impl;
/// Support for -fno-builtin* options as function attributes, overrides
/// information in global TargetLibraryInfoImpl.
BitVector OverrideAsUnavailable;
public:
explicit TargetLibraryInfo(const TargetLibraryInfoImpl &Impl,
std::optional<const Function *> F = std::nullopt)
: Impl(&Impl), OverrideAsUnavailable(NumLibFuncs) {
if (!F)
return;
if ((*F)->hasFnAttribute("no-builtins"))
disableAllFunctions();
else {
// Disable individual libc/libm calls in TargetLibraryInfo.
LibFunc LF;
AttributeSet FnAttrs = (*F)->getAttributes().getFnAttrs();
for (const Attribute &Attr : FnAttrs) {
if (!Attr.isStringAttribute())
continue;
auto AttrStr = Attr.getKindAsString();
if (!AttrStr.consume_front("no-builtin-"))
continue;
if (getLibFunc(AttrStr, LF))
setUnavailable(LF);
}
}
}
// Provide value semantics.
TargetLibraryInfo(const TargetLibraryInfo &TLI) = default;
TargetLibraryInfo(TargetLibraryInfo &&TLI)
: Impl(TLI.Impl), OverrideAsUnavailable(TLI.OverrideAsUnavailable) {}
TargetLibraryInfo &operator=(const TargetLibraryInfo &TLI) = default;
TargetLibraryInfo &operator=(TargetLibraryInfo &&TLI) {
Impl = TLI.Impl;
OverrideAsUnavailable = TLI.OverrideAsUnavailable;
return *this;
}
/// Determine whether a callee with the given TLI can be inlined into
/// caller with this TLI, based on 'nobuiltin' attributes. When requested,
/// allow inlining into a caller with a superset of the callee's nobuiltin
/// attributes, which is conservatively correct.
bool areInlineCompatible(const TargetLibraryInfo &CalleeTLI,
bool AllowCallerSuperset) const {
if (!AllowCallerSuperset)
return OverrideAsUnavailable == CalleeTLI.OverrideAsUnavailable;
BitVector B = OverrideAsUnavailable;
B |= CalleeTLI.OverrideAsUnavailable;
// We can inline if the union of the caller and callee's nobuiltin
// attributes is no stricter than the caller's nobuiltin attributes.
return B == OverrideAsUnavailable;
}
/// Return true if the function type FTy is valid for the library function
/// F, regardless of whether the function is available.
bool isValidProtoForLibFunc(const FunctionType &FTy, LibFunc F,
const Module &M) const {
return Impl->isValidProtoForLibFunc(FTy, F, M);
}
/// Searches for a particular function name.
///
/// If it is one of the known library functions, return true and set F to the
/// corresponding value.
bool getLibFunc(StringRef funcName, LibFunc &F) const {
return Impl->getLibFunc(funcName, F);
}
bool getLibFunc(const Function &FDecl, LibFunc &F) const {
return Impl->getLibFunc(FDecl, F);
}
/// If a callbase does not have the 'nobuiltin' attribute, return if the
/// called function is a known library function and set F to that function.
bool getLibFunc(const CallBase &CB, LibFunc &F) const {
return !CB.isNoBuiltin() && CB.getCalledFunction() &&
getLibFunc(*(CB.getCalledFunction()), F);
}
/// Disables all builtins.
///
/// This can be used for options like -fno-builtin.
void disableAllFunctions() LLVM_ATTRIBUTE_UNUSED {
OverrideAsUnavailable.set();
}
/// Forces a function to be marked as unavailable.
void setUnavailable(LibFunc F) LLVM_ATTRIBUTE_UNUSED {
OverrideAsUnavailable.set(F);
}
TargetLibraryInfoImpl::AvailabilityState getState(LibFunc F) const {
if (OverrideAsUnavailable[F])
return TargetLibraryInfoImpl::Unavailable;
return Impl->getState(F);
}
/// Tests whether a library function is available.
bool has(LibFunc F) const {
return getState(F) != TargetLibraryInfoImpl::Unavailable;
}
bool isFunctionVectorizable(StringRef F, const ElementCount &VF) const {
return Impl->isFunctionVectorizable(F, VF);
}
bool isFunctionVectorizable(StringRef F) const {
return Impl->isFunctionVectorizable(F);
}
StringRef getVectorizedFunction(StringRef F, const ElementCount &VF) const {
return Impl->getVectorizedFunction(F, VF);
}
/// Tests if the function is both available and a candidate for optimized code
/// generation.
bool hasOptimizedCodeGen(LibFunc F) const {
if (getState(F) == TargetLibraryInfoImpl::Unavailable)
return false;
switch (F) {
default: break;
case LibFunc_copysign: case LibFunc_copysignf: case LibFunc_copysignl:
case LibFunc_fabs: case LibFunc_fabsf: case LibFunc_fabsl:
case LibFunc_sin: case LibFunc_sinf: case LibFunc_sinl:
case LibFunc_cos: case LibFunc_cosf: case LibFunc_cosl:
case LibFunc_sqrt: case LibFunc_sqrtf: case LibFunc_sqrtl:
case LibFunc_sqrt_finite: case LibFunc_sqrtf_finite:
case LibFunc_sqrtl_finite:
case LibFunc_fmax: case LibFunc_fmaxf: case LibFunc_fmaxl:
case LibFunc_fmin: case LibFunc_fminf: case LibFunc_fminl:
case LibFunc_floor: case LibFunc_floorf: case LibFunc_floorl:
case LibFunc_nearbyint: case LibFunc_nearbyintf: case LibFunc_nearbyintl:
case LibFunc_ceil: case LibFunc_ceilf: case LibFunc_ceill:
case LibFunc_rint: case LibFunc_rintf: case LibFunc_rintl:
case LibFunc_round: case LibFunc_roundf: case LibFunc_roundl:
case LibFunc_trunc: case LibFunc_truncf: case LibFunc_truncl:
case LibFunc_log2: case LibFunc_log2f: case LibFunc_log2l:
case LibFunc_exp2: case LibFunc_exp2f: case LibFunc_exp2l:
case LibFunc_memcpy: case LibFunc_memset: case LibFunc_memmove:
case LibFunc_memcmp: case LibFunc_bcmp: case LibFunc_strcmp:
case LibFunc_strcpy: case LibFunc_stpcpy: case LibFunc_strlen:
case LibFunc_strnlen: case LibFunc_memchr: case LibFunc_mempcpy:
return true;
}
return false;
}
StringRef getName(LibFunc F) const {
auto State = getState(F);
if (State == TargetLibraryInfoImpl::Unavailable)
return StringRef();
if (State == TargetLibraryInfoImpl::StandardName)
return Impl->StandardNames[F];
assert(State == TargetLibraryInfoImpl::CustomName);
return Impl->CustomNames.find(F)->second;
}
static void initExtensionsForTriple(bool &ShouldExtI32Param,
bool &ShouldExtI32Return,
bool &ShouldSignExtI32Param,
bool &ShouldSignExtI32Return,
const Triple &T) {
ShouldExtI32Param = ShouldExtI32Return = false;
ShouldSignExtI32Param = ShouldSignExtI32Return = false;
// PowerPC64, Sparc64, SystemZ need signext/zeroext on i32 parameters and
// returns corresponding to C-level ints and unsigned ints.
if (T.isPPC64() || T.getArch() == Triple::sparcv9 ||
T.getArch() == Triple::systemz) {
ShouldExtI32Param = true;
ShouldExtI32Return = true;
}
// LoongArch, Mips, and riscv64, on the other hand, need signext on i32
// parameters corresponding to both signed and unsigned ints.
if (T.isLoongArch() || T.isMIPS() || T.isRISCV64()) {
ShouldSignExtI32Param = true;
}
// LoongArch and riscv64 need signext on i32 returns corresponding to both
// signed and unsigned ints.
if (T.isLoongArch() || T.isRISCV64()) {
ShouldSignExtI32Return = true;
}
}
/// Returns extension attribute kind to be used for i32 parameters
/// corresponding to C-level int or unsigned int. May be zeroext, signext,
/// or none.
private:
static Attribute::AttrKind getExtAttrForI32Param(bool ShouldExtI32Param_,
bool ShouldSignExtI32Param_,
bool Signed = true) {
if (ShouldExtI32Param_)
return Signed ? Attribute::SExt : Attribute::ZExt;
if (ShouldSignExtI32Param_)
return Attribute::SExt;
return Attribute::None;
}
public:
static Attribute::AttrKind getExtAttrForI32Param(const Triple &T,
bool Signed = true) {
bool ShouldExtI32Param, ShouldExtI32Return;
bool ShouldSignExtI32Param, ShouldSignExtI32Return;
initExtensionsForTriple(ShouldExtI32Param, ShouldExtI32Return,
ShouldSignExtI32Param, ShouldSignExtI32Return, T);
return getExtAttrForI32Param(ShouldExtI32Param, ShouldSignExtI32Param,
Signed);
}
Attribute::AttrKind getExtAttrForI32Param(bool Signed = true) const {
return getExtAttrForI32Param(Impl->ShouldExtI32Param,
Impl->ShouldSignExtI32Param, Signed);
}
/// Returns extension attribute kind to be used for i32 return values
/// corresponding to C-level int or unsigned int. May be zeroext, signext,
/// or none.
private:
static Attribute::AttrKind getExtAttrForI32Return(bool ShouldExtI32Return_,
bool ShouldSignExtI32Return_,
bool Signed) {
if (ShouldExtI32Return_)
return Signed ? Attribute::SExt : Attribute::ZExt;
if (ShouldSignExtI32Return_)
return Attribute::SExt;
return Attribute::None;
}
public:
static Attribute::AttrKind getExtAttrForI32Return(const Triple &T,
bool Signed = true) {
bool ShouldExtI32Param, ShouldExtI32Return;
bool ShouldSignExtI32Param, ShouldSignExtI32Return;
initExtensionsForTriple(ShouldExtI32Param, ShouldExtI32Return,
ShouldSignExtI32Param, ShouldSignExtI32Return, T);
return getExtAttrForI32Return(ShouldExtI32Return, ShouldSignExtI32Return,
Signed);
}
Attribute::AttrKind getExtAttrForI32Return(bool Signed = true) const {
return getExtAttrForI32Return(Impl->ShouldExtI32Return,
Impl->ShouldSignExtI32Return, Signed);
}
// Helper to create an AttributeList for args (and ret val) which all have
// the same signedness. Attributes in AL may be passed in to include them
// as well in the returned AttributeList.
AttributeList getAttrList(LLVMContext *C, ArrayRef<unsigned> ArgNos,
bool Signed, bool Ret = false,
AttributeList AL = AttributeList()) const {
if (auto AK = getExtAttrForI32Param(Signed))
for (auto ArgNo : ArgNos)
AL = AL.addParamAttribute(*C, ArgNo, AK);
if (Ret)
if (auto AK = getExtAttrForI32Return(Signed))
AL = AL.addRetAttribute(*C, AK);
return AL;
}
/// \copydoc TargetLibraryInfoImpl::getWCharSize()
unsigned getWCharSize(const Module &M) const {
return Impl->getWCharSize(M);
}
/// \copydoc TargetLibraryInfoImpl::getSizeTSize()
unsigned getSizeTSize(const Module &M) const { return Impl->getSizeTSize(M); }
/// \copydoc TargetLibraryInfoImpl::getIntSize()
unsigned getIntSize() const {
return Impl->getIntSize();
}
/// Handle invalidation from the pass manager.
///
/// If we try to invalidate this info, just return false. It cannot become
/// invalid even if the module or function changes.
bool invalidate(Module &, const PreservedAnalyses &,
ModuleAnalysisManager::Invalidator &) {
return false;
}
bool invalidate(Function &, const PreservedAnalyses &,
FunctionAnalysisManager::Invalidator &) {
return false;
}
/// Returns the largest vectorization factor used in the list of
/// vector functions.
void getWidestVF(StringRef ScalarF, ElementCount &FixedVF,
ElementCount &ScalableVF) const {
Impl->getWidestVF(ScalarF, FixedVF, ScalableVF);
}
/// Check if the function "F" is listed in a library known to LLVM.
bool isKnownVectorFunctionInLibrary(StringRef F) const {
return this->isFunctionVectorizable(F);
}
};
/// Analysis pass providing the \c TargetLibraryInfo.
///
/// Note that this pass's result cannot be invalidated, it is immutable for the
/// life of the module.
class TargetLibraryAnalysis : public AnalysisInfoMixin<TargetLibraryAnalysis> {
public:
typedef TargetLibraryInfo Result;
/// Default construct the library analysis.
///
/// This will use the module's triple to construct the library info for that
/// module.
TargetLibraryAnalysis() = default;
/// Construct a library analysis with baseline Module-level info.
///
/// This will be supplemented with Function-specific info in the Result.
TargetLibraryAnalysis(TargetLibraryInfoImpl BaselineInfoImpl)
: BaselineInfoImpl(std::move(BaselineInfoImpl)) {}
TargetLibraryInfo run(const Function &F, FunctionAnalysisManager &);
private:
friend AnalysisInfoMixin<TargetLibraryAnalysis>;
static AnalysisKey Key;
std::optional<TargetLibraryInfoImpl> BaselineInfoImpl;
};
class TargetLibraryInfoWrapperPass : public ImmutablePass {
TargetLibraryAnalysis TLA;
std::optional<TargetLibraryInfo> TLI;
virtual void anchor();
public:
static char ID;
TargetLibraryInfoWrapperPass();
explicit TargetLibraryInfoWrapperPass(const Triple &T);
explicit TargetLibraryInfoWrapperPass(const TargetLibraryInfoImpl &TLI);
TargetLibraryInfo &getTLI(const Function &F) {
FunctionAnalysisManager DummyFAM;
TLI = TLA.run(F, DummyFAM);
return *TLI;
}
};
} // end namespace llvm
#endif