| //===--- ScopeInfo.h - Information about a semantic context -----*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines FunctionScopeInfo and BlockScopeInfo. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CLANG_SEMA_SCOPE_INFO_H |
| #define LLVM_CLANG_SEMA_SCOPE_INFO_H |
| |
| #include "clang/AST/Type.h" |
| #include "clang/Basic/PartialDiagnostic.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/SmallVector.h" |
| |
| namespace clang { |
| |
| class BlockDecl; |
| class CXXMethodDecl; |
| class IdentifierInfo; |
| class LabelDecl; |
| class ReturnStmt; |
| class Scope; |
| class SwitchStmt; |
| class VarDecl; |
| |
| namespace sema { |
| |
| /// \brief Contains information about the compound statement currently being |
| /// parsed. |
| class CompoundScopeInfo { |
| public: |
| CompoundScopeInfo() |
| : HasEmptyLoopBodies(false) { } |
| |
| /// \brief Whether this compound stamement contains `for' or `while' loops |
| /// with empty bodies. |
| bool HasEmptyLoopBodies; |
| |
| void setHasEmptyLoopBodies() { |
| HasEmptyLoopBodies = true; |
| } |
| }; |
| |
| class PossiblyUnreachableDiag { |
| public: |
| PartialDiagnostic PD; |
| SourceLocation Loc; |
| const Stmt *stmt; |
| |
| PossiblyUnreachableDiag(const PartialDiagnostic &PD, SourceLocation Loc, |
| const Stmt *stmt) |
| : PD(PD), Loc(Loc), stmt(stmt) {} |
| }; |
| |
| /// \brief Retains information about a function, method, or block that is |
| /// currently being parsed. |
| class FunctionScopeInfo { |
| protected: |
| enum ScopeKind { |
| SK_Function, |
| SK_Block, |
| SK_Lambda |
| }; |
| |
| public: |
| /// \brief What kind of scope we are describing. |
| /// |
| ScopeKind Kind; |
| |
| /// \brief Whether this function contains a VLA, \@try, try, C++ |
| /// initializer, or anything else that can't be jumped past. |
| bool HasBranchProtectedScope; |
| |
| /// \brief Whether this function contains any switches or direct gotos. |
| bool HasBranchIntoScope; |
| |
| /// \brief Whether this function contains any indirect gotos. |
| bool HasIndirectGoto; |
| |
| /// A flag that is set when parsing a -dealloc method and no [super dealloc] |
| /// call was found yet. |
| bool ObjCShouldCallSuperDealloc; |
| |
| /// A flag that is set when parsing a -finalize method and no [super finalize] |
| /// call was found yet. |
| bool ObjCShouldCallSuperFinalize; |
| |
| /// \brief Used to determine if errors occurred in this function or block. |
| DiagnosticErrorTrap ErrorTrap; |
| |
| /// SwitchStack - This is the current set of active switch statements in the |
| /// block. |
| SmallVector<SwitchStmt*, 8> SwitchStack; |
| |
| /// \brief The list of return statements that occur within the function or |
| /// block, if there is any chance of applying the named return value |
| /// optimization, or if we need to infer a return type. |
| SmallVector<ReturnStmt*, 4> Returns; |
| |
| /// \brief The stack of currently active compound stamement scopes in the |
| /// function. |
| SmallVector<CompoundScopeInfo, 4> CompoundScopes; |
| |
| /// \brief A list of PartialDiagnostics created but delayed within the |
| /// current function scope. These diagnostics are vetted for reachability |
| /// prior to being emitted. |
| SmallVector<PossiblyUnreachableDiag, 4> PossiblyUnreachableDiags; |
| |
| void setHasBranchIntoScope() { |
| HasBranchIntoScope = true; |
| } |
| |
| void setHasBranchProtectedScope() { |
| HasBranchProtectedScope = true; |
| } |
| |
| void setHasIndirectGoto() { |
| HasIndirectGoto = true; |
| } |
| |
| bool NeedsScopeChecking() const { |
| return HasIndirectGoto || |
| (HasBranchProtectedScope && HasBranchIntoScope); |
| } |
| |
| FunctionScopeInfo(DiagnosticsEngine &Diag) |
| : Kind(SK_Function), |
| HasBranchProtectedScope(false), |
| HasBranchIntoScope(false), |
| HasIndirectGoto(false), |
| ObjCShouldCallSuperDealloc(false), |
| ObjCShouldCallSuperFinalize(false), |
| ErrorTrap(Diag) { } |
| |
| virtual ~FunctionScopeInfo(); |
| |
| /// \brief Clear out the information in this function scope, making it |
| /// suitable for reuse. |
| void Clear(); |
| |
| static bool classof(const FunctionScopeInfo *FSI) { return true; } |
| }; |
| |
| class CapturingScopeInfo : public FunctionScopeInfo { |
| public: |
| enum ImplicitCaptureStyle { |
| ImpCap_None, ImpCap_LambdaByval, ImpCap_LambdaByref, ImpCap_Block |
| }; |
| |
| ImplicitCaptureStyle ImpCaptureStyle; |
| |
| class Capture { |
| // There are two categories of capture: capturing 'this', and capturing |
| // local variables. There are three ways to capture a local variable: |
| // capture by copy in the C++11 sense, capture by reference |
| // in the C++11 sense, and __block capture. Lambdas explicitly specify |
| // capture by copy or capture by reference. For blocks, __block capture |
| // applies to variables with that annotation, variables of reference type |
| // are captured by reference, and other variables are captured by copy. |
| enum CaptureKind { |
| Cap_This, Cap_ByCopy, Cap_ByRef, Cap_Block |
| }; |
| |
| // The variable being captured (if we are not capturing 'this'), |
| // and misc bits descibing the capture. |
| llvm::PointerIntPair<VarDecl*, 2, CaptureKind> VarAndKind; |
| |
| // Expression to initialize a field of the given type, and whether this |
| // is a nested capture; the expression is only required if we are |
| // capturing ByVal and the variable's type has a non-trivial |
| // copy constructor. |
| llvm::PointerIntPair<Expr*, 1, bool> CopyExprAndNested; |
| |
| /// \brief The source location at which the first capture occurred.. |
| SourceLocation Loc; |
| |
| /// \brief The location of the ellipsis that expands a parameter pack. |
| SourceLocation EllipsisLoc; |
| |
| /// \brief The type as it was captured, which is in effect the type of the |
| /// non-static data member that would hold the capture. |
| QualType CaptureType; |
| |
| public: |
| Capture(VarDecl *Var, bool block, bool byRef, bool isNested, |
| SourceLocation Loc, SourceLocation EllipsisLoc, |
| QualType CaptureType, Expr *Cpy) |
| : VarAndKind(Var, block ? Cap_Block : byRef ? Cap_ByRef : Cap_ByCopy), |
| CopyExprAndNested(Cpy, isNested), Loc(Loc), EllipsisLoc(EllipsisLoc), |
| CaptureType(CaptureType){} |
| |
| enum IsThisCapture { ThisCapture }; |
| Capture(IsThisCapture, bool isNested, SourceLocation Loc, |
| QualType CaptureType, Expr *Cpy) |
| : VarAndKind(0, Cap_This), CopyExprAndNested(Cpy, isNested), Loc(Loc), |
| EllipsisLoc(), CaptureType(CaptureType) { } |
| |
| bool isThisCapture() const { return VarAndKind.getInt() == Cap_This; } |
| bool isVariableCapture() const { return !isThisCapture(); } |
| bool isCopyCapture() const { return VarAndKind.getInt() == Cap_ByCopy; } |
| bool isReferenceCapture() const { return VarAndKind.getInt() == Cap_ByRef; } |
| bool isBlockCapture() const { return VarAndKind.getInt() == Cap_Block; } |
| bool isNested() { return CopyExprAndNested.getInt(); } |
| |
| VarDecl *getVariable() const { |
| return VarAndKind.getPointer(); |
| } |
| |
| /// \brief Retrieve the location at which this variable was captured. |
| SourceLocation getLocation() const { return Loc; } |
| |
| /// \brief Retrieve the source location of the ellipsis, whose presence |
| /// indicates that the capture is a pack expansion. |
| SourceLocation getEllipsisLoc() const { return EllipsisLoc; } |
| |
| /// \brief Retrieve the capture type for this capture, which is effectively |
| /// the type of the non-static data member in the lambda/block structure |
| /// that would store this capture. |
| QualType getCaptureType() const { return CaptureType; } |
| |
| Expr *getCopyExpr() const { |
| return CopyExprAndNested.getPointer(); |
| } |
| }; |
| |
| CapturingScopeInfo(DiagnosticsEngine &Diag, ImplicitCaptureStyle Style) |
| : FunctionScopeInfo(Diag), ImpCaptureStyle(Style), CXXThisCaptureIndex(0), |
| HasImplicitReturnType(false) |
| {} |
| |
| /// CaptureMap - A map of captured variables to (index+1) into Captures. |
| llvm::DenseMap<VarDecl*, unsigned> CaptureMap; |
| |
| /// CXXThisCaptureIndex - The (index+1) of the capture of 'this'; |
| /// zero if 'this' is not captured. |
| unsigned CXXThisCaptureIndex; |
| |
| /// Captures - The captures. |
| SmallVector<Capture, 4> Captures; |
| |
| /// \brief - Whether the target type of return statements in this context |
| /// is deduced (e.g. a lambda or block with omitted return type). |
| bool HasImplicitReturnType; |
| |
| /// ReturnType - The target type of return statements in this context, |
| /// or null if unknown. |
| QualType ReturnType; |
| |
| void addCapture(VarDecl *Var, bool isBlock, bool isByref, bool isNested, |
| SourceLocation Loc, SourceLocation EllipsisLoc, |
| QualType CaptureType, Expr *Cpy) { |
| Captures.push_back(Capture(Var, isBlock, isByref, isNested, Loc, |
| EllipsisLoc, CaptureType, Cpy)); |
| CaptureMap[Var] = Captures.size(); |
| } |
| |
| void addThisCapture(bool isNested, SourceLocation Loc, QualType CaptureType, |
| Expr *Cpy) { |
| Captures.push_back(Capture(Capture::ThisCapture, isNested, Loc, CaptureType, |
| Cpy)); |
| CXXThisCaptureIndex = Captures.size(); |
| } |
| |
| /// \brief Determine whether the C++ 'this' is captured. |
| bool isCXXThisCaptured() const { return CXXThisCaptureIndex != 0; } |
| |
| /// \brief Retrieve the capture of C++ 'this', if it has been captured. |
| Capture &getCXXThisCapture() { |
| assert(isCXXThisCaptured() && "this has not been captured"); |
| return Captures[CXXThisCaptureIndex - 1]; |
| } |
| |
| /// \brief Determine whether the given variable has been captured. |
| bool isCaptured(VarDecl *Var) const { |
| return CaptureMap.count(Var); |
| } |
| |
| /// \brief Retrieve the capture of the given variable, if it has been |
| /// captured already. |
| Capture &getCapture(VarDecl *Var) { |
| assert(isCaptured(Var) && "Variable has not been captured"); |
| return Captures[CaptureMap[Var] - 1]; |
| } |
| |
| const Capture &getCapture(VarDecl *Var) const { |
| llvm::DenseMap<VarDecl*, unsigned>::const_iterator Known |
| = CaptureMap.find(Var); |
| assert(Known != CaptureMap.end() && "Variable has not been captured"); |
| return Captures[Known->second - 1]; |
| } |
| |
| static bool classof(const FunctionScopeInfo *FSI) { |
| return FSI->Kind == SK_Block || FSI->Kind == SK_Lambda; |
| } |
| static bool classof(const CapturingScopeInfo *BSI) { return true; } |
| }; |
| |
| /// \brief Retains information about a block that is currently being parsed. |
| class BlockScopeInfo : public CapturingScopeInfo { |
| public: |
| BlockDecl *TheDecl; |
| |
| /// TheScope - This is the scope for the block itself, which contains |
| /// arguments etc. |
| Scope *TheScope; |
| |
| /// BlockType - The function type of the block, if one was given. |
| /// Its return type may be BuiltinType::Dependent. |
| QualType FunctionType; |
| |
| BlockScopeInfo(DiagnosticsEngine &Diag, Scope *BlockScope, BlockDecl *Block) |
| : CapturingScopeInfo(Diag, ImpCap_Block), TheDecl(Block), |
| TheScope(BlockScope) |
| { |
| Kind = SK_Block; |
| } |
| |
| virtual ~BlockScopeInfo(); |
| |
| static bool classof(const FunctionScopeInfo *FSI) { |
| return FSI->Kind == SK_Block; |
| } |
| static bool classof(const BlockScopeInfo *BSI) { return true; } |
| }; |
| |
| class LambdaScopeInfo : public CapturingScopeInfo { |
| public: |
| /// \brief The class that describes the lambda. |
| CXXRecordDecl *Lambda; |
| |
| /// \brief The class that describes the lambda. |
| CXXMethodDecl *CallOperator; |
| |
| /// \brief Source range covering the lambda introducer [...]. |
| SourceRange IntroducerRange; |
| |
| /// \brief The number of captures in the \c Captures list that are |
| /// explicit captures. |
| unsigned NumExplicitCaptures; |
| |
| /// \brief Whether this is a mutable lambda. |
| bool Mutable; |
| |
| /// \brief Whether the (empty) parameter list is explicit. |
| bool ExplicitParams; |
| |
| /// \brief Whether any of the capture expressions requires cleanups. |
| bool ExprNeedsCleanups; |
| |
| /// \brief Whether the lambda contains an unexpanded parameter pack. |
| bool ContainsUnexpandedParameterPack; |
| |
| /// \brief Variables used to index into by-copy array captures. |
| llvm::SmallVector<VarDecl *, 4> ArrayIndexVars; |
| |
| /// \brief Offsets into the ArrayIndexVars array at which each capture starts |
| /// its list of array index variables. |
| llvm::SmallVector<unsigned, 4> ArrayIndexStarts; |
| |
| LambdaScopeInfo(DiagnosticsEngine &Diag, CXXRecordDecl *Lambda, |
| CXXMethodDecl *CallOperator) |
| : CapturingScopeInfo(Diag, ImpCap_None), Lambda(Lambda), |
| CallOperator(CallOperator), NumExplicitCaptures(0), Mutable(false), |
| ExprNeedsCleanups(false), ContainsUnexpandedParameterPack(false) |
| { |
| Kind = SK_Lambda; |
| } |
| |
| virtual ~LambdaScopeInfo(); |
| |
| /// \brief Note when |
| void finishedExplicitCaptures() { |
| NumExplicitCaptures = Captures.size(); |
| } |
| |
| static bool classof(const FunctionScopeInfo *FSI) { |
| return FSI->Kind == SK_Lambda; |
| } |
| static bool classof(const LambdaScopeInfo *BSI) { return true; } |
| |
| }; |
| |
| } |
| } |
| |
| #endif |