| //===--- SemaCUDA.cpp - Semantic Analysis for CUDA constructs -------------===// |
| // |
| // 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 implements semantic analysis for CUDA constructs. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/Decl.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/Basic/Cuda.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Sema/Lookup.h" |
| #include "clang/Sema/ScopeInfo.h" |
| #include "clang/Sema/Sema.h" |
| #include "clang/Sema/SemaDiagnostic.h" |
| #include "clang/Sema/SemaInternal.h" |
| #include "clang/Sema/Template.h" |
| #include "llvm/ADT/Optional.h" |
| #include "llvm/ADT/SmallVector.h" |
| using namespace clang; |
| |
| template <typename AttrT> static bool hasExplicitAttr(const VarDecl *D) { |
| if (!D) |
| return false; |
| if (auto *A = D->getAttr<AttrT>()) |
| return !A->isImplicit(); |
| return false; |
| } |
| |
| void Sema::PushForceCUDAHostDevice() { |
| assert(getLangOpts().CUDA && "Should only be called during CUDA compilation"); |
| ForceCUDAHostDeviceDepth++; |
| } |
| |
| bool Sema::PopForceCUDAHostDevice() { |
| assert(getLangOpts().CUDA && "Should only be called during CUDA compilation"); |
| if (ForceCUDAHostDeviceDepth == 0) |
| return false; |
| ForceCUDAHostDeviceDepth--; |
| return true; |
| } |
| |
| ExprResult Sema::ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc, |
| MultiExprArg ExecConfig, |
| SourceLocation GGGLoc) { |
| FunctionDecl *ConfigDecl = Context.getcudaConfigureCallDecl(); |
| if (!ConfigDecl) |
| return ExprError(Diag(LLLLoc, diag::err_undeclared_var_use) |
| << getCudaConfigureFuncName()); |
| QualType ConfigQTy = ConfigDecl->getType(); |
| |
| DeclRefExpr *ConfigDR = new (Context) |
| DeclRefExpr(Context, ConfigDecl, false, ConfigQTy, VK_LValue, LLLLoc); |
| MarkFunctionReferenced(LLLLoc, ConfigDecl); |
| |
| return BuildCallExpr(S, ConfigDR, LLLLoc, ExecConfig, GGGLoc, nullptr, |
| /*IsExecConfig=*/true); |
| } |
| |
| Sema::CUDAFunctionTarget |
| Sema::IdentifyCUDATarget(const ParsedAttributesView &Attrs) { |
| bool HasHostAttr = false; |
| bool HasDeviceAttr = false; |
| bool HasGlobalAttr = false; |
| bool HasInvalidTargetAttr = false; |
| for (const ParsedAttr &AL : Attrs) { |
| switch (AL.getKind()) { |
| case ParsedAttr::AT_CUDAGlobal: |
| HasGlobalAttr = true; |
| break; |
| case ParsedAttr::AT_CUDAHost: |
| HasHostAttr = true; |
| break; |
| case ParsedAttr::AT_CUDADevice: |
| HasDeviceAttr = true; |
| break; |
| case ParsedAttr::AT_CUDAInvalidTarget: |
| HasInvalidTargetAttr = true; |
| break; |
| default: |
| break; |
| } |
| } |
| |
| if (HasInvalidTargetAttr) |
| return CFT_InvalidTarget; |
| |
| if (HasGlobalAttr) |
| return CFT_Global; |
| |
| if (HasHostAttr && HasDeviceAttr) |
| return CFT_HostDevice; |
| |
| if (HasDeviceAttr) |
| return CFT_Device; |
| |
| return CFT_Host; |
| } |
| |
| template <typename A> |
| static bool hasAttr(const FunctionDecl *D, bool IgnoreImplicitAttr) { |
| return D->hasAttrs() && llvm::any_of(D->getAttrs(), [&](Attr *Attribute) { |
| return isa<A>(Attribute) && |
| !(IgnoreImplicitAttr && Attribute->isImplicit()); |
| }); |
| } |
| |
| /// IdentifyCUDATarget - Determine the CUDA compilation target for this function |
| Sema::CUDAFunctionTarget Sema::IdentifyCUDATarget(const FunctionDecl *D, |
| bool IgnoreImplicitHDAttr) { |
| // Code that lives outside a function is run on the host. |
| if (D == nullptr) |
| return CFT_Host; |
| |
| if (D->hasAttr<CUDAInvalidTargetAttr>()) |
| return CFT_InvalidTarget; |
| |
| if (D->hasAttr<CUDAGlobalAttr>()) |
| return CFT_Global; |
| |
| if (hasAttr<CUDADeviceAttr>(D, IgnoreImplicitHDAttr)) { |
| if (hasAttr<CUDAHostAttr>(D, IgnoreImplicitHDAttr)) |
| return CFT_HostDevice; |
| return CFT_Device; |
| } else if (hasAttr<CUDAHostAttr>(D, IgnoreImplicitHDAttr)) { |
| return CFT_Host; |
| } else if ((D->isImplicit() || !D->isUserProvided()) && |
| !IgnoreImplicitHDAttr) { |
| // Some implicit declarations (like intrinsic functions) are not marked. |
| // Set the most lenient target on them for maximal flexibility. |
| return CFT_HostDevice; |
| } |
| |
| return CFT_Host; |
| } |
| |
| /// IdentifyTarget - Determine the CUDA compilation target for this variable. |
| Sema::CUDAVariableTarget Sema::IdentifyCUDATarget(const VarDecl *Var) { |
| if (Var->hasAttr<HIPManagedAttr>()) |
| return CVT_Unified; |
| if (Var->isConstexpr() && !hasExplicitAttr<CUDAConstantAttr>(Var)) |
| return CVT_Both; |
| if (Var->getType().isConstQualified() && Var->hasAttr<CUDAConstantAttr>() && |
| !hasExplicitAttr<CUDAConstantAttr>(Var)) |
| return CVT_Both; |
| if (Var->hasAttr<CUDADeviceAttr>() || Var->hasAttr<CUDAConstantAttr>() || |
| Var->hasAttr<CUDASharedAttr>() || |
| Var->getType()->isCUDADeviceBuiltinSurfaceType() || |
| Var->getType()->isCUDADeviceBuiltinTextureType()) |
| return CVT_Device; |
| // Function-scope static variable without explicit device or constant |
| // attribute are emitted |
| // - on both sides in host device functions |
| // - on device side in device or global functions |
| if (auto *FD = dyn_cast<FunctionDecl>(Var->getDeclContext())) { |
| switch (IdentifyCUDATarget(FD)) { |
| case CFT_HostDevice: |
| return CVT_Both; |
| case CFT_Device: |
| case CFT_Global: |
| return CVT_Device; |
| default: |
| return CVT_Host; |
| } |
| } |
| return CVT_Host; |
| } |
| |
| // * CUDA Call preference table |
| // |
| // F - from, |
| // T - to |
| // Ph - preference in host mode |
| // Pd - preference in device mode |
| // H - handled in (x) |
| // Preferences: N:native, SS:same side, HD:host-device, WS:wrong side, --:never. |
| // |
| // | F | T | Ph | Pd | H | |
| // |----+----+-----+-----+-----+ |
| // | d | d | N | N | (c) | |
| // | d | g | -- | -- | (a) | |
| // | d | h | -- | -- | (e) | |
| // | d | hd | HD | HD | (b) | |
| // | g | d | N | N | (c) | |
| // | g | g | -- | -- | (a) | |
| // | g | h | -- | -- | (e) | |
| // | g | hd | HD | HD | (b) | |
| // | h | d | -- | -- | (e) | |
| // | h | g | N | N | (c) | |
| // | h | h | N | N | (c) | |
| // | h | hd | HD | HD | (b) | |
| // | hd | d | WS | SS | (d) | |
| // | hd | g | SS | -- |(d/a)| |
| // | hd | h | SS | WS | (d) | |
| // | hd | hd | HD | HD | (b) | |
| |
| Sema::CUDAFunctionPreference |
| Sema::IdentifyCUDAPreference(const FunctionDecl *Caller, |
| const FunctionDecl *Callee) { |
| assert(Callee && "Callee must be valid."); |
| CUDAFunctionTarget CallerTarget = IdentifyCUDATarget(Caller); |
| CUDAFunctionTarget CalleeTarget = IdentifyCUDATarget(Callee); |
| |
| // If one of the targets is invalid, the check always fails, no matter what |
| // the other target is. |
| if (CallerTarget == CFT_InvalidTarget || CalleeTarget == CFT_InvalidTarget) |
| return CFP_Never; |
| |
| // (a) Can't call global from some contexts until we support CUDA's |
| // dynamic parallelism. |
| if (CalleeTarget == CFT_Global && |
| (CallerTarget == CFT_Global || CallerTarget == CFT_Device)) |
| return CFP_Never; |
| |
| // (b) Calling HostDevice is OK for everyone. |
| if (CalleeTarget == CFT_HostDevice) |
| return CFP_HostDevice; |
| |
| // (c) Best case scenarios |
| if (CalleeTarget == CallerTarget || |
| (CallerTarget == CFT_Host && CalleeTarget == CFT_Global) || |
| (CallerTarget == CFT_Global && CalleeTarget == CFT_Device)) |
| return CFP_Native; |
| |
| // (d) HostDevice behavior depends on compilation mode. |
| if (CallerTarget == CFT_HostDevice) { |
| // It's OK to call a compilation-mode matching function from an HD one. |
| if ((getLangOpts().CUDAIsDevice && CalleeTarget == CFT_Device) || |
| (!getLangOpts().CUDAIsDevice && |
| (CalleeTarget == CFT_Host || CalleeTarget == CFT_Global))) |
| return CFP_SameSide; |
| |
| // Calls from HD to non-mode-matching functions (i.e., to host functions |
| // when compiling in device mode or to device functions when compiling in |
| // host mode) are allowed at the sema level, but eventually rejected if |
| // they're ever codegened. TODO: Reject said calls earlier. |
| return CFP_WrongSide; |
| } |
| |
| // (e) Calling across device/host boundary is not something you should do. |
| if ((CallerTarget == CFT_Host && CalleeTarget == CFT_Device) || |
| (CallerTarget == CFT_Device && CalleeTarget == CFT_Host) || |
| (CallerTarget == CFT_Global && CalleeTarget == CFT_Host)) |
| return CFP_Never; |
| |
| llvm_unreachable("All cases should've been handled by now."); |
| } |
| |
| template <typename AttrT> static bool hasImplicitAttr(const FunctionDecl *D) { |
| if (!D) |
| return false; |
| if (auto *A = D->getAttr<AttrT>()) |
| return A->isImplicit(); |
| return D->isImplicit(); |
| } |
| |
| bool Sema::isCUDAImplicitHostDeviceFunction(const FunctionDecl *D) { |
| bool IsImplicitDevAttr = hasImplicitAttr<CUDADeviceAttr>(D); |
| bool IsImplicitHostAttr = hasImplicitAttr<CUDAHostAttr>(D); |
| return IsImplicitDevAttr && IsImplicitHostAttr; |
| } |
| |
| void Sema::EraseUnwantedCUDAMatches( |
| const FunctionDecl *Caller, |
| SmallVectorImpl<std::pair<DeclAccessPair, FunctionDecl *>> &Matches) { |
| if (Matches.size() <= 1) |
| return; |
| |
| using Pair = std::pair<DeclAccessPair, FunctionDecl*>; |
| |
| // Gets the CUDA function preference for a call from Caller to Match. |
| auto GetCFP = [&](const Pair &Match) { |
| return IdentifyCUDAPreference(Caller, Match.second); |
| }; |
| |
| // Find the best call preference among the functions in Matches. |
| CUDAFunctionPreference BestCFP = GetCFP(*std::max_element( |
| Matches.begin(), Matches.end(), |
| [&](const Pair &M1, const Pair &M2) { return GetCFP(M1) < GetCFP(M2); })); |
| |
| // Erase all functions with lower priority. |
| llvm::erase_if(Matches, |
| [&](const Pair &Match) { return GetCFP(Match) < BestCFP; }); |
| } |
| |
| /// When an implicitly-declared special member has to invoke more than one |
| /// base/field special member, conflicts may occur in the targets of these |
| /// members. For example, if one base's member __host__ and another's is |
| /// __device__, it's a conflict. |
| /// This function figures out if the given targets \param Target1 and |
| /// \param Target2 conflict, and if they do not it fills in |
| /// \param ResolvedTarget with a target that resolves for both calls. |
| /// \return true if there's a conflict, false otherwise. |
| static bool |
| resolveCalleeCUDATargetConflict(Sema::CUDAFunctionTarget Target1, |
| Sema::CUDAFunctionTarget Target2, |
| Sema::CUDAFunctionTarget *ResolvedTarget) { |
| // Only free functions and static member functions may be global. |
| assert(Target1 != Sema::CFT_Global); |
| assert(Target2 != Sema::CFT_Global); |
| |
| if (Target1 == Sema::CFT_HostDevice) { |
| *ResolvedTarget = Target2; |
| } else if (Target2 == Sema::CFT_HostDevice) { |
| *ResolvedTarget = Target1; |
| } else if (Target1 != Target2) { |
| return true; |
| } else { |
| *ResolvedTarget = Target1; |
| } |
| |
| return false; |
| } |
| |
| bool Sema::inferCUDATargetForImplicitSpecialMember(CXXRecordDecl *ClassDecl, |
| CXXSpecialMember CSM, |
| CXXMethodDecl *MemberDecl, |
| bool ConstRHS, |
| bool Diagnose) { |
| // If the defaulted special member is defined lexically outside of its |
| // owning class, or the special member already has explicit device or host |
| // attributes, do not infer. |
| bool InClass = MemberDecl->getLexicalParent() == MemberDecl->getParent(); |
| bool HasH = MemberDecl->hasAttr<CUDAHostAttr>(); |
| bool HasD = MemberDecl->hasAttr<CUDADeviceAttr>(); |
| bool HasExplicitAttr = |
| (HasD && !MemberDecl->getAttr<CUDADeviceAttr>()->isImplicit()) || |
| (HasH && !MemberDecl->getAttr<CUDAHostAttr>()->isImplicit()); |
| if (!InClass || HasExplicitAttr) |
| return false; |
| |
| llvm::Optional<CUDAFunctionTarget> InferredTarget; |
| |
| // We're going to invoke special member lookup; mark that these special |
| // members are called from this one, and not from its caller. |
| ContextRAII MethodContext(*this, MemberDecl); |
| |
| // Look for special members in base classes that should be invoked from here. |
| // Infer the target of this member base on the ones it should call. |
| // Skip direct and indirect virtual bases for abstract classes. |
| llvm::SmallVector<const CXXBaseSpecifier *, 16> Bases; |
| for (const auto &B : ClassDecl->bases()) { |
| if (!B.isVirtual()) { |
| Bases.push_back(&B); |
| } |
| } |
| |
| if (!ClassDecl->isAbstract()) { |
| for (const auto &VB : ClassDecl->vbases()) { |
| Bases.push_back(&VB); |
| } |
| } |
| |
| for (const auto *B : Bases) { |
| const RecordType *BaseType = B->getType()->getAs<RecordType>(); |
| if (!BaseType) { |
| continue; |
| } |
| |
| CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl()); |
| Sema::SpecialMemberOverloadResult SMOR = |
| LookupSpecialMember(BaseClassDecl, CSM, |
| /* ConstArg */ ConstRHS, |
| /* VolatileArg */ false, |
| /* RValueThis */ false, |
| /* ConstThis */ false, |
| /* VolatileThis */ false); |
| |
| if (!SMOR.getMethod()) |
| continue; |
| |
| CUDAFunctionTarget BaseMethodTarget = IdentifyCUDATarget(SMOR.getMethod()); |
| if (!InferredTarget.hasValue()) { |
| InferredTarget = BaseMethodTarget; |
| } else { |
| bool ResolutionError = resolveCalleeCUDATargetConflict( |
| InferredTarget.getValue(), BaseMethodTarget, |
| InferredTarget.getPointer()); |
| if (ResolutionError) { |
| if (Diagnose) { |
| Diag(ClassDecl->getLocation(), |
| diag::note_implicit_member_target_infer_collision) |
| << (unsigned)CSM << InferredTarget.getValue() << BaseMethodTarget; |
| } |
| MemberDecl->addAttr(CUDAInvalidTargetAttr::CreateImplicit(Context)); |
| return true; |
| } |
| } |
| } |
| |
| // Same as for bases, but now for special members of fields. |
| for (const auto *F : ClassDecl->fields()) { |
| if (F->isInvalidDecl()) { |
| continue; |
| } |
| |
| const RecordType *FieldType = |
| Context.getBaseElementType(F->getType())->getAs<RecordType>(); |
| if (!FieldType) { |
| continue; |
| } |
| |
| CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(FieldType->getDecl()); |
| Sema::SpecialMemberOverloadResult SMOR = |
| LookupSpecialMember(FieldRecDecl, CSM, |
| /* ConstArg */ ConstRHS && !F->isMutable(), |
| /* VolatileArg */ false, |
| /* RValueThis */ false, |
| /* ConstThis */ false, |
| /* VolatileThis */ false); |
| |
| if (!SMOR.getMethod()) |
| continue; |
| |
| CUDAFunctionTarget FieldMethodTarget = |
| IdentifyCUDATarget(SMOR.getMethod()); |
| if (!InferredTarget.hasValue()) { |
| InferredTarget = FieldMethodTarget; |
| } else { |
| bool ResolutionError = resolveCalleeCUDATargetConflict( |
| InferredTarget.getValue(), FieldMethodTarget, |
| InferredTarget.getPointer()); |
| if (ResolutionError) { |
| if (Diagnose) { |
| Diag(ClassDecl->getLocation(), |
| diag::note_implicit_member_target_infer_collision) |
| << (unsigned)CSM << InferredTarget.getValue() |
| << FieldMethodTarget; |
| } |
| MemberDecl->addAttr(CUDAInvalidTargetAttr::CreateImplicit(Context)); |
| return true; |
| } |
| } |
| } |
| |
| |
| // If no target was inferred, mark this member as __host__ __device__; |
| // it's the least restrictive option that can be invoked from any target. |
| bool NeedsH = true, NeedsD = true; |
| if (InferredTarget.hasValue()) { |
| if (InferredTarget.getValue() == CFT_Device) |
| NeedsH = false; |
| else if (InferredTarget.getValue() == CFT_Host) |
| NeedsD = false; |
| } |
| |
| // We either setting attributes first time, or the inferred ones must match |
| // previously set ones. |
| if (NeedsD && !HasD) |
| MemberDecl->addAttr(CUDADeviceAttr::CreateImplicit(Context)); |
| if (NeedsH && !HasH) |
| MemberDecl->addAttr(CUDAHostAttr::CreateImplicit(Context)); |
| |
| return false; |
| } |
| |
| bool Sema::isEmptyCudaConstructor(SourceLocation Loc, CXXConstructorDecl *CD) { |
| if (!CD->isDefined() && CD->isTemplateInstantiation()) |
| InstantiateFunctionDefinition(Loc, CD->getFirstDecl()); |
| |
| // (E.2.3.1, CUDA 7.5) A constructor for a class type is considered |
| // empty at a point in the translation unit, if it is either a |
| // trivial constructor |
| if (CD->isTrivial()) |
| return true; |
| |
| // ... or it satisfies all of the following conditions: |
| // The constructor function has been defined. |
| // The constructor function has no parameters, |
| // and the function body is an empty compound statement. |
| if (!(CD->hasTrivialBody() && CD->getNumParams() == 0)) |
| return false; |
| |
| // Its class has no virtual functions and no virtual base classes. |
| if (CD->getParent()->isDynamicClass()) |
| return false; |
| |
| // Union ctor does not call ctors of its data members. |
| if (CD->getParent()->isUnion()) |
| return true; |
| |
| // The only form of initializer allowed is an empty constructor. |
| // This will recursively check all base classes and member initializers |
| if (!llvm::all_of(CD->inits(), [&](const CXXCtorInitializer *CI) { |
| if (const CXXConstructExpr *CE = |
| dyn_cast<CXXConstructExpr>(CI->getInit())) |
| return isEmptyCudaConstructor(Loc, CE->getConstructor()); |
| return false; |
| })) |
| return false; |
| |
| return true; |
| } |
| |
| bool Sema::isEmptyCudaDestructor(SourceLocation Loc, CXXDestructorDecl *DD) { |
| // No destructor -> no problem. |
| if (!DD) |
| return true; |
| |
| if (!DD->isDefined() && DD->isTemplateInstantiation()) |
| InstantiateFunctionDefinition(Loc, DD->getFirstDecl()); |
| |
| // (E.2.3.1, CUDA 7.5) A destructor for a class type is considered |
| // empty at a point in the translation unit, if it is either a |
| // trivial constructor |
| if (DD->isTrivial()) |
| return true; |
| |
| // ... or it satisfies all of the following conditions: |
| // The destructor function has been defined. |
| // and the function body is an empty compound statement. |
| if (!DD->hasTrivialBody()) |
| return false; |
| |
| const CXXRecordDecl *ClassDecl = DD->getParent(); |
| |
| // Its class has no virtual functions and no virtual base classes. |
| if (ClassDecl->isDynamicClass()) |
| return false; |
| |
| // Union does not have base class and union dtor does not call dtors of its |
| // data members. |
| if (DD->getParent()->isUnion()) |
| return true; |
| |
| // Only empty destructors are allowed. This will recursively check |
| // destructors for all base classes... |
| if (!llvm::all_of(ClassDecl->bases(), [&](const CXXBaseSpecifier &BS) { |
| if (CXXRecordDecl *RD = BS.getType()->getAsCXXRecordDecl()) |
| return isEmptyCudaDestructor(Loc, RD->getDestructor()); |
| return true; |
| })) |
| return false; |
| |
| // ... and member fields. |
| if (!llvm::all_of(ClassDecl->fields(), [&](const FieldDecl *Field) { |
| if (CXXRecordDecl *RD = Field->getType() |
| ->getBaseElementTypeUnsafe() |
| ->getAsCXXRecordDecl()) |
| return isEmptyCudaDestructor(Loc, RD->getDestructor()); |
| return true; |
| })) |
| return false; |
| |
| return true; |
| } |
| |
| namespace { |
| enum CUDAInitializerCheckKind { |
| CICK_DeviceOrConstant, // Check initializer for device/constant variable |
| CICK_Shared, // Check initializer for shared variable |
| }; |
| |
| bool IsDependentVar(VarDecl *VD) { |
| if (VD->getType()->isDependentType()) |
| return true; |
| if (const auto *Init = VD->getInit()) |
| return Init->isValueDependent(); |
| return false; |
| } |
| |
| // Check whether a variable has an allowed initializer for a CUDA device side |
| // variable with global storage. \p VD may be a host variable to be checked for |
| // potential promotion to device side variable. |
| // |
| // CUDA/HIP allows only empty constructors as initializers for global |
| // variables (see E.2.3.1, CUDA 7.5). The same restriction also applies to all |
| // __shared__ variables whether they are local or not (they all are implicitly |
| // static in CUDA). One exception is that CUDA allows constant initializers |
| // for __constant__ and __device__ variables. |
| bool HasAllowedCUDADeviceStaticInitializer(Sema &S, VarDecl *VD, |
| CUDAInitializerCheckKind CheckKind) { |
| assert(!VD->isInvalidDecl() && VD->hasGlobalStorage()); |
| assert(!IsDependentVar(VD) && "do not check dependent var"); |
| const Expr *Init = VD->getInit(); |
| auto IsEmptyInit = [&](const Expr *Init) { |
| if (!Init) |
| return true; |
| if (const auto *CE = dyn_cast<CXXConstructExpr>(Init)) { |
| return S.isEmptyCudaConstructor(VD->getLocation(), CE->getConstructor()); |
| } |
| return false; |
| }; |
| auto IsConstantInit = [&](const Expr *Init) { |
| assert(Init); |
| return Init->isConstantInitializer(S.Context, |
| VD->getType()->isReferenceType()); |
| }; |
| auto HasEmptyDtor = [&](VarDecl *VD) { |
| if (const auto *RD = VD->getType()->getAsCXXRecordDecl()) |
| return S.isEmptyCudaDestructor(VD->getLocation(), RD->getDestructor()); |
| return true; |
| }; |
| if (CheckKind == CICK_Shared) |
| return IsEmptyInit(Init) && HasEmptyDtor(VD); |
| return S.LangOpts.GPUAllowDeviceInit || |
| ((IsEmptyInit(Init) || IsConstantInit(Init)) && HasEmptyDtor(VD)); |
| } |
| } // namespace |
| |
| void Sema::checkAllowedCUDAInitializer(VarDecl *VD) { |
| // Do not check dependent variables since the ctor/dtor/initializer are not |
| // determined. Do it after instantiation. |
| if (VD->isInvalidDecl() || !VD->hasInit() || !VD->hasGlobalStorage() || |
| IsDependentVar(VD)) |
| return; |
| const Expr *Init = VD->getInit(); |
| bool IsSharedVar = VD->hasAttr<CUDASharedAttr>(); |
| bool IsDeviceOrConstantVar = |
| !IsSharedVar && |
| (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>()); |
| if (IsDeviceOrConstantVar || IsSharedVar) { |
| if (HasAllowedCUDADeviceStaticInitializer( |
| *this, VD, IsSharedVar ? CICK_Shared : CICK_DeviceOrConstant)) |
| return; |
| Diag(VD->getLocation(), |
| IsSharedVar ? diag::err_shared_var_init : diag::err_dynamic_var_init) |
| << Init->getSourceRange(); |
| VD->setInvalidDecl(); |
| } else { |
| // This is a host-side global variable. Check that the initializer is |
| // callable from the host side. |
| const FunctionDecl *InitFn = nullptr; |
| if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init)) { |
| InitFn = CE->getConstructor(); |
| } else if (const CallExpr *CE = dyn_cast<CallExpr>(Init)) { |
| InitFn = CE->getDirectCallee(); |
| } |
| if (InitFn) { |
| CUDAFunctionTarget InitFnTarget = IdentifyCUDATarget(InitFn); |
| if (InitFnTarget != CFT_Host && InitFnTarget != CFT_HostDevice) { |
| Diag(VD->getLocation(), diag::err_ref_bad_target_global_initializer) |
| << InitFnTarget << InitFn; |
| Diag(InitFn->getLocation(), diag::note_previous_decl) << InitFn; |
| VD->setInvalidDecl(); |
| } |
| } |
| } |
| } |
| |
| // With -fcuda-host-device-constexpr, an unattributed constexpr function is |
| // treated as implicitly __host__ __device__, unless: |
| // * it is a variadic function (device-side variadic functions are not |
| // allowed), or |
| // * a __device__ function with this signature was already declared, in which |
| // case in which case we output an error, unless the __device__ decl is in a |
| // system header, in which case we leave the constexpr function unattributed. |
| // |
| // In addition, all function decls are treated as __host__ __device__ when |
| // ForceCUDAHostDeviceDepth > 0 (corresponding to code within a |
| // #pragma clang force_cuda_host_device_begin/end |
| // pair). |
| void Sema::maybeAddCUDAHostDeviceAttrs(FunctionDecl *NewD, |
| const LookupResult &Previous) { |
| assert(getLangOpts().CUDA && "Should only be called during CUDA compilation"); |
| |
| if (ForceCUDAHostDeviceDepth > 0) { |
| if (!NewD->hasAttr<CUDAHostAttr>()) |
| NewD->addAttr(CUDAHostAttr::CreateImplicit(Context)); |
| if (!NewD->hasAttr<CUDADeviceAttr>()) |
| NewD->addAttr(CUDADeviceAttr::CreateImplicit(Context)); |
| return; |
| } |
| |
| if (!getLangOpts().CUDAHostDeviceConstexpr || !NewD->isConstexpr() || |
| NewD->isVariadic() || NewD->hasAttr<CUDAHostAttr>() || |
| NewD->hasAttr<CUDADeviceAttr>() || NewD->hasAttr<CUDAGlobalAttr>()) |
| return; |
| |
| // Is D a __device__ function with the same signature as NewD, ignoring CUDA |
| // attributes? |
| auto IsMatchingDeviceFn = [&](NamedDecl *D) { |
| if (UsingShadowDecl *Using = dyn_cast<UsingShadowDecl>(D)) |
| D = Using->getTargetDecl(); |
| FunctionDecl *OldD = D->getAsFunction(); |
| return OldD && OldD->hasAttr<CUDADeviceAttr>() && |
| !OldD->hasAttr<CUDAHostAttr>() && |
| !IsOverload(NewD, OldD, /* UseMemberUsingDeclRules = */ false, |
| /* ConsiderCudaAttrs = */ false); |
| }; |
| auto It = llvm::find_if(Previous, IsMatchingDeviceFn); |
| if (It != Previous.end()) { |
| // We found a __device__ function with the same name and signature as NewD |
| // (ignoring CUDA attrs). This is an error unless that function is defined |
| // in a system header, in which case we simply return without making NewD |
| // host+device. |
| NamedDecl *Match = *It; |
| if (!getSourceManager().isInSystemHeader(Match->getLocation())) { |
| Diag(NewD->getLocation(), |
| diag::err_cuda_unattributed_constexpr_cannot_overload_device) |
| << NewD; |
| Diag(Match->getLocation(), |
| diag::note_cuda_conflicting_device_function_declared_here); |
| } |
| return; |
| } |
| |
| NewD->addAttr(CUDAHostAttr::CreateImplicit(Context)); |
| NewD->addAttr(CUDADeviceAttr::CreateImplicit(Context)); |
| } |
| |
| // TODO: `__constant__` memory may be a limited resource for certain targets. |
| // A safeguard may be needed at the end of compilation pipeline if |
| // `__constant__` memory usage goes beyond limit. |
| void Sema::MaybeAddCUDAConstantAttr(VarDecl *VD) { |
| // Do not promote dependent variables since the cotr/dtor/initializer are |
| // not determined. Do it after instantiation. |
| if (getLangOpts().CUDAIsDevice && !VD->hasAttr<CUDAConstantAttr>() && |
| !VD->hasAttr<CUDAConstantAttr>() && !VD->hasAttr<CUDASharedAttr>() && |
| (VD->isFileVarDecl() || VD->isStaticDataMember()) && |
| !IsDependentVar(VD) && |
| (VD->isConstexpr() || (VD->getType().isConstQualified() && |
| HasAllowedCUDADeviceStaticInitializer( |
| *this, VD, CICK_DeviceOrConstant)))) { |
| VD->addAttr(CUDAConstantAttr::CreateImplicit(getASTContext())); |
| } |
| } |
| |
| Sema::SemaDiagnosticBuilder Sema::CUDADiagIfDeviceCode(SourceLocation Loc, |
| unsigned DiagID) { |
| assert(getLangOpts().CUDA && "Should only be called during CUDA compilation"); |
| SemaDiagnosticBuilder::Kind DiagKind = [&] { |
| if (!isa<FunctionDecl>(CurContext)) |
| return SemaDiagnosticBuilder::K_Nop; |
| switch (CurrentCUDATarget()) { |
| case CFT_Global: |
| case CFT_Device: |
| return SemaDiagnosticBuilder::K_Immediate; |
| case CFT_HostDevice: |
| // An HD function counts as host code if we're compiling for host, and |
| // device code if we're compiling for device. Defer any errors in device |
| // mode until the function is known-emitted. |
| if (!getLangOpts().CUDAIsDevice) |
| return SemaDiagnosticBuilder::K_Nop; |
| if (IsLastErrorImmediate && Diags.getDiagnosticIDs()->isBuiltinNote(DiagID)) |
| return SemaDiagnosticBuilder::K_Immediate; |
| return (getEmissionStatus(cast<FunctionDecl>(CurContext)) == |
| FunctionEmissionStatus::Emitted) |
| ? SemaDiagnosticBuilder::K_ImmediateWithCallStack |
| : SemaDiagnosticBuilder::K_Deferred; |
| default: |
| return SemaDiagnosticBuilder::K_Nop; |
| } |
| }(); |
| return SemaDiagnosticBuilder(DiagKind, Loc, DiagID, |
| dyn_cast<FunctionDecl>(CurContext), *this); |
| } |
| |
| Sema::SemaDiagnosticBuilder Sema::CUDADiagIfHostCode(SourceLocation Loc, |
| unsigned DiagID) { |
| assert(getLangOpts().CUDA && "Should only be called during CUDA compilation"); |
| SemaDiagnosticBuilder::Kind DiagKind = [&] { |
| if (!isa<FunctionDecl>(CurContext)) |
| return SemaDiagnosticBuilder::K_Nop; |
| switch (CurrentCUDATarget()) { |
| case CFT_Host: |
| return SemaDiagnosticBuilder::K_Immediate; |
| case CFT_HostDevice: |
| // An HD function counts as host code if we're compiling for host, and |
| // device code if we're compiling for device. Defer any errors in device |
| // mode until the function is known-emitted. |
| if (getLangOpts().CUDAIsDevice) |
| return SemaDiagnosticBuilder::K_Nop; |
| if (IsLastErrorImmediate && Diags.getDiagnosticIDs()->isBuiltinNote(DiagID)) |
| return SemaDiagnosticBuilder::K_Immediate; |
| return (getEmissionStatus(cast<FunctionDecl>(CurContext)) == |
| FunctionEmissionStatus::Emitted) |
| ? SemaDiagnosticBuilder::K_ImmediateWithCallStack |
| : SemaDiagnosticBuilder::K_Deferred; |
| default: |
| return SemaDiagnosticBuilder::K_Nop; |
| } |
| }(); |
| return SemaDiagnosticBuilder(DiagKind, Loc, DiagID, |
| dyn_cast<FunctionDecl>(CurContext), *this); |
| } |
| |
| bool Sema::CheckCUDACall(SourceLocation Loc, FunctionDecl *Callee) { |
| assert(getLangOpts().CUDA && "Should only be called during CUDA compilation"); |
| assert(Callee && "Callee may not be null."); |
| |
| auto &ExprEvalCtx = ExprEvalContexts.back(); |
| if (ExprEvalCtx.isUnevaluated() || ExprEvalCtx.isConstantEvaluated()) |
| return true; |
| |
| // FIXME: Is bailing out early correct here? Should we instead assume that |
| // the caller is a global initializer? |
| FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext); |
| if (!Caller) |
| return true; |
| |
| // If the caller is known-emitted, mark the callee as known-emitted. |
| // Otherwise, mark the call in our call graph so we can traverse it later. |
| bool CallerKnownEmitted = |
| getEmissionStatus(Caller) == FunctionEmissionStatus::Emitted; |
| SemaDiagnosticBuilder::Kind DiagKind = [this, Caller, Callee, |
| CallerKnownEmitted] { |
| switch (IdentifyCUDAPreference(Caller, Callee)) { |
| case CFP_Never: |
| case CFP_WrongSide: |
| assert(Caller && "Never/wrongSide calls require a non-null caller"); |
| // If we know the caller will be emitted, we know this wrong-side call |
| // will be emitted, so it's an immediate error. Otherwise, defer the |
| // error until we know the caller is emitted. |
| return CallerKnownEmitted |
| ? SemaDiagnosticBuilder::K_ImmediateWithCallStack |
| : SemaDiagnosticBuilder::K_Deferred; |
| default: |
| return SemaDiagnosticBuilder::K_Nop; |
| } |
| }(); |
| |
| if (DiagKind == SemaDiagnosticBuilder::K_Nop) |
| return true; |
| |
| // Avoid emitting this error twice for the same location. Using a hashtable |
| // like this is unfortunate, but because we must continue parsing as normal |
| // after encountering a deferred error, it's otherwise very tricky for us to |
| // ensure that we only emit this deferred error once. |
| if (!LocsWithCUDACallDiags.insert({Caller, Loc}).second) |
| return true; |
| |
| SemaDiagnosticBuilder(DiagKind, Loc, diag::err_ref_bad_target, Caller, *this) |
| << IdentifyCUDATarget(Callee) << /*function*/ 0 << Callee |
| << IdentifyCUDATarget(Caller); |
| if (!Callee->getBuiltinID()) |
| SemaDiagnosticBuilder(DiagKind, Callee->getLocation(), |
| diag::note_previous_decl, Caller, *this) |
| << Callee; |
| return DiagKind != SemaDiagnosticBuilder::K_Immediate && |
| DiagKind != SemaDiagnosticBuilder::K_ImmediateWithCallStack; |
| } |
| |
| // Check the wrong-sided reference capture of lambda for CUDA/HIP. |
| // A lambda function may capture a stack variable by reference when it is |
| // defined and uses the capture by reference when the lambda is called. When |
| // the capture and use happen on different sides, the capture is invalid and |
| // should be diagnosed. |
| void Sema::CUDACheckLambdaCapture(CXXMethodDecl *Callee, |
| const sema::Capture &Capture) { |
| // In host compilation we only need to check lambda functions emitted on host |
| // side. In such lambda functions, a reference capture is invalid only |
| // if the lambda structure is populated by a device function or kernel then |
| // is passed to and called by a host function. However that is impossible, |
| // since a device function or kernel can only call a device function, also a |
| // kernel cannot pass a lambda back to a host function since we cannot |
| // define a kernel argument type which can hold the lambda before the lambda |
| // itself is defined. |
| if (!LangOpts.CUDAIsDevice) |
| return; |
| |
| // File-scope lambda can only do init captures for global variables, which |
| // results in passing by value for these global variables. |
| FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext); |
| if (!Caller) |
| return; |
| |
| // In device compilation, we only need to check lambda functions which are |
| // emitted on device side. For such lambdas, a reference capture is invalid |
| // only if the lambda structure is populated by a host function then passed |
| // to and called in a device function or kernel. |
| bool CalleeIsDevice = Callee->hasAttr<CUDADeviceAttr>(); |
| bool CallerIsHost = |
| !Caller->hasAttr<CUDAGlobalAttr>() && !Caller->hasAttr<CUDADeviceAttr>(); |
| bool ShouldCheck = CalleeIsDevice && CallerIsHost; |
| if (!ShouldCheck || !Capture.isReferenceCapture()) |
| return; |
| auto DiagKind = SemaDiagnosticBuilder::K_Deferred; |
| if (Capture.isVariableCapture()) { |
| SemaDiagnosticBuilder(DiagKind, Capture.getLocation(), |
| diag::err_capture_bad_target, Callee, *this) |
| << Capture.getVariable(); |
| } else if (Capture.isThisCapture()) { |
| // Capture of this pointer is allowed since this pointer may be pointing to |
| // managed memory which is accessible on both device and host sides. It only |
| // results in invalid memory access if this pointer points to memory not |
| // accessible on device side. |
| SemaDiagnosticBuilder(DiagKind, Capture.getLocation(), |
| diag::warn_maybe_capture_bad_target_this_ptr, Callee, |
| *this); |
| } |
| return; |
| } |
| |
| void Sema::CUDASetLambdaAttrs(CXXMethodDecl *Method) { |
| assert(getLangOpts().CUDA && "Should only be called during CUDA compilation"); |
| if (Method->hasAttr<CUDAHostAttr>() || Method->hasAttr<CUDADeviceAttr>()) |
| return; |
| Method->addAttr(CUDADeviceAttr::CreateImplicit(Context)); |
| Method->addAttr(CUDAHostAttr::CreateImplicit(Context)); |
| } |
| |
| void Sema::checkCUDATargetOverload(FunctionDecl *NewFD, |
| const LookupResult &Previous) { |
| assert(getLangOpts().CUDA && "Should only be called during CUDA compilation"); |
| CUDAFunctionTarget NewTarget = IdentifyCUDATarget(NewFD); |
| for (NamedDecl *OldND : Previous) { |
| FunctionDecl *OldFD = OldND->getAsFunction(); |
| if (!OldFD) |
| continue; |
| |
| CUDAFunctionTarget OldTarget = IdentifyCUDATarget(OldFD); |
| // Don't allow HD and global functions to overload other functions with the |
| // same signature. We allow overloading based on CUDA attributes so that |
| // functions can have different implementations on the host and device, but |
| // HD/global functions "exist" in some sense on both the host and device, so |
| // should have the same implementation on both sides. |
| if (NewTarget != OldTarget && |
| ((NewTarget == CFT_HostDevice) || (OldTarget == CFT_HostDevice) || |
| (NewTarget == CFT_Global) || (OldTarget == CFT_Global)) && |
| !IsOverload(NewFD, OldFD, /* UseMemberUsingDeclRules = */ false, |
| /* ConsiderCudaAttrs = */ false)) { |
| Diag(NewFD->getLocation(), diag::err_cuda_ovl_target) |
| << NewTarget << NewFD->getDeclName() << OldTarget << OldFD; |
| Diag(OldFD->getLocation(), diag::note_previous_declaration); |
| NewFD->setInvalidDecl(); |
| break; |
| } |
| } |
| } |
| |
| template <typename AttrTy> |
| static void copyAttrIfPresent(Sema &S, FunctionDecl *FD, |
| const FunctionDecl &TemplateFD) { |
| if (AttrTy *Attribute = TemplateFD.getAttr<AttrTy>()) { |
| AttrTy *Clone = Attribute->clone(S.Context); |
| Clone->setInherited(true); |
| FD->addAttr(Clone); |
| } |
| } |
| |
| void Sema::inheritCUDATargetAttrs(FunctionDecl *FD, |
| const FunctionTemplateDecl &TD) { |
| const FunctionDecl &TemplateFD = *TD.getTemplatedDecl(); |
| copyAttrIfPresent<CUDAGlobalAttr>(*this, FD, TemplateFD); |
| copyAttrIfPresent<CUDAHostAttr>(*this, FD, TemplateFD); |
| copyAttrIfPresent<CUDADeviceAttr>(*this, FD, TemplateFD); |
| } |
| |
| std::string Sema::getCudaConfigureFuncName() const { |
| if (getLangOpts().HIP) |
| return getLangOpts().HIPUseNewLaunchAPI ? "__hipPushCallConfiguration" |
| : "hipConfigureCall"; |
| |
| // New CUDA kernel launch sequence. |
| if (CudaFeatureEnabled(Context.getTargetInfo().getSDKVersion(), |
| CudaFeature::CUDA_USES_NEW_LAUNCH)) |
| return "__cudaPushCallConfiguration"; |
| |
| // Legacy CUDA kernel configuration call |
| return "cudaConfigureCall"; |
| } |