| //===----- CGCall.h - Encapsulate calling convention details ----*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // These classes wrap the information about a call or function |
| // definition used to handle ABI compliancy. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CLANG_LIB_CODEGEN_CGCALL_H |
| #define LLVM_CLANG_LIB_CODEGEN_CGCALL_H |
| |
| #include "CGValue.h" |
| #include "EHScopeStack.h" |
| #include "clang/AST/CanonicalType.h" |
| #include "clang/AST/Type.h" |
| #include "llvm/IR/Value.h" |
| |
| // FIXME: Restructure so we don't have to expose so much stuff. |
| #include "ABIInfo.h" |
| |
| namespace llvm { |
| class AttributeList; |
| class Function; |
| class Type; |
| class Value; |
| } |
| |
| namespace clang { |
| class ASTContext; |
| class Decl; |
| class FunctionDecl; |
| class ObjCMethodDecl; |
| class VarDecl; |
| |
| namespace CodeGen { |
| |
| /// Abstract information about a function or function prototype. |
| class CGCalleeInfo { |
| /// \brief The function prototype of the callee. |
| const FunctionProtoType *CalleeProtoTy; |
| /// \brief The function declaration of the callee. |
| const Decl *CalleeDecl; |
| |
| public: |
| explicit CGCalleeInfo() : CalleeProtoTy(nullptr), CalleeDecl(nullptr) {} |
| CGCalleeInfo(const FunctionProtoType *calleeProtoTy, const Decl *calleeDecl) |
| : CalleeProtoTy(calleeProtoTy), CalleeDecl(calleeDecl) {} |
| CGCalleeInfo(const FunctionProtoType *calleeProtoTy) |
| : CalleeProtoTy(calleeProtoTy), CalleeDecl(nullptr) {} |
| CGCalleeInfo(const Decl *calleeDecl) |
| : CalleeProtoTy(nullptr), CalleeDecl(calleeDecl) {} |
| |
| const FunctionProtoType *getCalleeFunctionProtoType() const { |
| return CalleeProtoTy; |
| } |
| const Decl *getCalleeDecl() const { return CalleeDecl; } |
| }; |
| |
| /// All available information about a concrete callee. |
| class CGCallee { |
| enum class SpecialKind : uintptr_t { |
| Invalid, |
| Builtin, |
| PseudoDestructor, |
| |
| Last = PseudoDestructor |
| }; |
| |
| struct BuiltinInfoStorage { |
| const FunctionDecl *Decl; |
| unsigned ID; |
| }; |
| struct PseudoDestructorInfoStorage { |
| const CXXPseudoDestructorExpr *Expr; |
| }; |
| |
| SpecialKind KindOrFunctionPointer; |
| union { |
| CGCalleeInfo AbstractInfo; |
| BuiltinInfoStorage BuiltinInfo; |
| PseudoDestructorInfoStorage PseudoDestructorInfo; |
| }; |
| |
| explicit CGCallee(SpecialKind kind) : KindOrFunctionPointer(kind) {} |
| |
| CGCallee(const FunctionDecl *builtinDecl, unsigned builtinID) |
| : KindOrFunctionPointer(SpecialKind::Builtin) { |
| BuiltinInfo.Decl = builtinDecl; |
| BuiltinInfo.ID = builtinID; |
| } |
| |
| public: |
| CGCallee() : KindOrFunctionPointer(SpecialKind::Invalid) {} |
| |
| /// Construct a callee. Call this constructor directly when this |
| /// isn't a direct call. |
| CGCallee(const CGCalleeInfo &abstractInfo, llvm::Value *functionPtr) |
| : KindOrFunctionPointer(SpecialKind(uintptr_t(functionPtr))) { |
| AbstractInfo = abstractInfo; |
| assert(functionPtr && "configuring callee without function pointer"); |
| assert(functionPtr->getType()->isPointerTy()); |
| assert(functionPtr->getType()->getPointerElementType()->isFunctionTy()); |
| } |
| |
| static CGCallee forBuiltin(unsigned builtinID, |
| const FunctionDecl *builtinDecl) { |
| CGCallee result(SpecialKind::Builtin); |
| result.BuiltinInfo.Decl = builtinDecl; |
| result.BuiltinInfo.ID = builtinID; |
| return result; |
| } |
| |
| static CGCallee forPseudoDestructor(const CXXPseudoDestructorExpr *E) { |
| CGCallee result(SpecialKind::PseudoDestructor); |
| result.PseudoDestructorInfo.Expr = E; |
| return result; |
| } |
| |
| static CGCallee forDirect(llvm::Constant *functionPtr, |
| const CGCalleeInfo &abstractInfo = CGCalleeInfo()) { |
| return CGCallee(abstractInfo, functionPtr); |
| } |
| |
| bool isBuiltin() const { |
| return KindOrFunctionPointer == SpecialKind::Builtin; |
| } |
| const FunctionDecl *getBuiltinDecl() const { |
| assert(isBuiltin()); |
| return BuiltinInfo.Decl; |
| } |
| unsigned getBuiltinID() const { |
| assert(isBuiltin()); |
| return BuiltinInfo.ID; |
| } |
| |
| bool isPseudoDestructor() const { |
| return KindOrFunctionPointer == SpecialKind::PseudoDestructor; |
| } |
| const CXXPseudoDestructorExpr *getPseudoDestructorExpr() const { |
| assert(isPseudoDestructor()); |
| return PseudoDestructorInfo.Expr; |
| } |
| |
| bool isOrdinary() const { |
| return uintptr_t(KindOrFunctionPointer) > uintptr_t(SpecialKind::Last); |
| } |
| const CGCalleeInfo &getAbstractInfo() const { |
| assert(isOrdinary()); |
| return AbstractInfo; |
| } |
| llvm::Value *getFunctionPointer() const { |
| assert(isOrdinary()); |
| return reinterpret_cast<llvm::Value*>(uintptr_t(KindOrFunctionPointer)); |
| } |
| llvm::FunctionType *getFunctionType() const { |
| return cast<llvm::FunctionType>( |
| getFunctionPointer()->getType()->getPointerElementType()); |
| } |
| void setFunctionPointer(llvm::Value *functionPtr) { |
| assert(isOrdinary()); |
| KindOrFunctionPointer = SpecialKind(uintptr_t(functionPtr)); |
| } |
| }; |
| |
| struct CallArg { |
| RValue RV; |
| QualType Ty; |
| bool NeedsCopy; |
| CallArg(RValue rv, QualType ty, bool needscopy) |
| : RV(rv), Ty(ty), NeedsCopy(needscopy) |
| { } |
| }; |
| |
| /// CallArgList - Type for representing both the value and type of |
| /// arguments in a call. |
| class CallArgList : |
| public SmallVector<CallArg, 16> { |
| public: |
| CallArgList() : StackBase(nullptr) {} |
| |
| struct Writeback { |
| /// The original argument. Note that the argument l-value |
| /// is potentially null. |
| LValue Source; |
| |
| /// The temporary alloca. |
| Address Temporary; |
| |
| /// A value to "use" after the writeback, or null. |
| llvm::Value *ToUse; |
| }; |
| |
| struct CallArgCleanup { |
| EHScopeStack::stable_iterator Cleanup; |
| |
| /// The "is active" insertion point. This instruction is temporary and |
| /// will be removed after insertion. |
| llvm::Instruction *IsActiveIP; |
| }; |
| |
| void add(RValue rvalue, QualType type, bool needscopy = false) { |
| push_back(CallArg(rvalue, type, needscopy)); |
| } |
| |
| /// Add all the arguments from another CallArgList to this one. After doing |
| /// this, the old CallArgList retains its list of arguments, but must not |
| /// be used to emit a call. |
| void addFrom(const CallArgList &other) { |
| insert(end(), other.begin(), other.end()); |
| Writebacks.insert(Writebacks.end(), |
| other.Writebacks.begin(), other.Writebacks.end()); |
| CleanupsToDeactivate.insert(CleanupsToDeactivate.end(), |
| other.CleanupsToDeactivate.begin(), |
| other.CleanupsToDeactivate.end()); |
| assert(!(StackBase && other.StackBase) && "can't merge stackbases"); |
| if (!StackBase) |
| StackBase = other.StackBase; |
| } |
| |
| void addWriteback(LValue srcLV, Address temporary, |
| llvm::Value *toUse) { |
| Writeback writeback = { srcLV, temporary, toUse }; |
| Writebacks.push_back(writeback); |
| } |
| |
| bool hasWritebacks() const { return !Writebacks.empty(); } |
| |
| typedef llvm::iterator_range<SmallVectorImpl<Writeback>::const_iterator> |
| writeback_const_range; |
| |
| writeback_const_range writebacks() const { |
| return writeback_const_range(Writebacks.begin(), Writebacks.end()); |
| } |
| |
| void addArgCleanupDeactivation(EHScopeStack::stable_iterator Cleanup, |
| llvm::Instruction *IsActiveIP) { |
| CallArgCleanup ArgCleanup; |
| ArgCleanup.Cleanup = Cleanup; |
| ArgCleanup.IsActiveIP = IsActiveIP; |
| CleanupsToDeactivate.push_back(ArgCleanup); |
| } |
| |
| ArrayRef<CallArgCleanup> getCleanupsToDeactivate() const { |
| return CleanupsToDeactivate; |
| } |
| |
| void allocateArgumentMemory(CodeGenFunction &CGF); |
| llvm::Instruction *getStackBase() const { return StackBase; } |
| void freeArgumentMemory(CodeGenFunction &CGF) const; |
| |
| /// \brief Returns if we're using an inalloca struct to pass arguments in |
| /// memory. |
| bool isUsingInAlloca() const { return StackBase; } |
| |
| private: |
| SmallVector<Writeback, 1> Writebacks; |
| |
| /// Deactivate these cleanups immediately before making the call. This |
| /// is used to cleanup objects that are owned by the callee once the call |
| /// occurs. |
| SmallVector<CallArgCleanup, 1> CleanupsToDeactivate; |
| |
| /// The stacksave call. It dominates all of the argument evaluation. |
| llvm::CallInst *StackBase; |
| }; |
| |
| /// FunctionArgList - Type for representing both the decl and type |
| /// of parameters to a function. The decl must be either a |
| /// ParmVarDecl or ImplicitParamDecl. |
| class FunctionArgList : public SmallVector<const VarDecl*, 16> { |
| }; |
| |
| /// ReturnValueSlot - Contains the address where the return value of a |
| /// function can be stored, and whether the address is volatile or not. |
| class ReturnValueSlot { |
| llvm::PointerIntPair<llvm::Value *, 2, unsigned int> Value; |
| CharUnits Alignment; |
| |
| // Return value slot flags |
| enum Flags { |
| IS_VOLATILE = 0x1, |
| IS_UNUSED = 0x2, |
| }; |
| |
| public: |
| ReturnValueSlot() {} |
| ReturnValueSlot(Address Addr, bool IsVolatile, bool IsUnused = false) |
| : Value(Addr.isValid() ? Addr.getPointer() : nullptr, |
| (IsVolatile ? IS_VOLATILE : 0) | (IsUnused ? IS_UNUSED : 0)), |
| Alignment(Addr.isValid() ? Addr.getAlignment() : CharUnits::Zero()) {} |
| |
| bool isNull() const { return !getValue().isValid(); } |
| |
| bool isVolatile() const { return Value.getInt() & IS_VOLATILE; } |
| Address getValue() const { return Address(Value.getPointer(), Alignment); } |
| bool isUnused() const { return Value.getInt() & IS_UNUSED; } |
| }; |
| |
| } // end namespace CodeGen |
| } // end namespace clang |
| |
| #endif |