Coverage Report

Created: 2020-09-19 12:23

/Users/buildslave/jenkins/workspace/coverage/llvm-project/clang/lib/CodeGen/CGCall.h
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//===----- CGCall.h - Encapsulate calling convention details ----*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// These classes wrap the information about a call or function
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// definition used to handle ABI compliancy.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CLANG_LIB_CODEGEN_CGCALL_H
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#define LLVM_CLANG_LIB_CODEGEN_CGCALL_H
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#include "CGValue.h"
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#include "EHScopeStack.h"
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#include "clang/AST/ASTFwd.h"
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#include "clang/AST/CanonicalType.h"
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#include "clang/AST/GlobalDecl.h"
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#include "clang/AST/Type.h"
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#include "llvm/IR/Value.h"
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// FIXME: Restructure so we don't have to expose so much stuff.
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#include "ABIInfo.h"
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namespace llvm {
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class AttributeList;
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class Function;
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class Type;
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class Value;
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} // namespace llvm
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namespace clang {
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class ASTContext;
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class Decl;
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class FunctionDecl;
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class ObjCMethodDecl;
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class VarDecl;
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namespace CodeGen {
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/// Abstract information about a function or function prototype.
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class CGCalleeInfo {
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  /// The function prototype of the callee.
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  const FunctionProtoType *CalleeProtoTy;
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  /// The function declaration of the callee.
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  GlobalDecl CalleeDecl;
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public:
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13.8k
  explicit CGCalleeInfo() : CalleeProtoTy(nullptr), CalleeDecl() {}
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  CGCalleeInfo(const FunctionProtoType *calleeProtoTy, GlobalDecl calleeDecl)
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4.53k
      : CalleeProtoTy(calleeProtoTy), CalleeDecl(calleeDecl) {}
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  CGCalleeInfo(const FunctionProtoType *calleeProtoTy)
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      : CalleeProtoTy(calleeProtoTy), CalleeDecl() {}
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  CGCalleeInfo(GlobalDecl calleeDecl)
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619k
      : CalleeProtoTy(nullptr), CalleeDecl(calleeDecl) {}
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636k
  const FunctionProtoType *getCalleeFunctionProtoType() const {
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636k
    return CalleeProtoTy;
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636k
  }
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1.43M
  const GlobalDecl getCalleeDecl() const { return CalleeDecl; }
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};
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/// All available information about a concrete callee.
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class CGCallee {
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  enum class SpecialKind : uintptr_t {
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    Invalid,
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    Builtin,
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    PseudoDestructor,
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    Virtual,
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    Last = Virtual
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  };
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  struct BuiltinInfoStorage {
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    const FunctionDecl *Decl;
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    unsigned ID;
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  };
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  struct PseudoDestructorInfoStorage {
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    const CXXPseudoDestructorExpr *Expr;
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  };
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  struct VirtualInfoStorage {
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    const CallExpr *CE;
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    GlobalDecl MD;
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    Address Addr;
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    llvm::FunctionType *FTy;
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  };
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  SpecialKind KindOrFunctionPointer;
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  union {
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    CGCalleeInfo AbstractInfo;
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    BuiltinInfoStorage BuiltinInfo;
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    PseudoDestructorInfoStorage PseudoDestructorInfo;
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    VirtualInfoStorage VirtualInfo;
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  };
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61.6k
  explicit CGCallee(SpecialKind kind) : KindOrFunctionPointer(kind) {}
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  CGCallee(const FunctionDecl *builtinDecl, unsigned builtinID)
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0
      : KindOrFunctionPointer(SpecialKind::Builtin) {
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0
    BuiltinInfo.Decl = builtinDecl;
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0
    BuiltinInfo.ID = builtinID;
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0
  }
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public:
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91.6k
  CGCallee() : KindOrFunctionPointer(SpecialKind::Invalid) {}
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  /// Construct a callee.  Call this constructor directly when this
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  /// isn't a direct call.
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  CGCallee(const CGCalleeInfo &abstractInfo, llvm::Value *functionPtr)
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319k
      : KindOrFunctionPointer(SpecialKind(uintptr_t(functionPtr))) {
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    AbstractInfo = abstractInfo;
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319k
    assert(functionPtr && "configuring callee without function pointer");
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    assert(functionPtr->getType()->isPointerTy());
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    assert(functionPtr->getType()->getPointerElementType()->isFunctionTy());
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  }
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  static CGCallee forBuiltin(unsigned builtinID,
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                             const FunctionDecl *builtinDecl) {
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    CGCallee result(SpecialKind::Builtin);
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    result.BuiltinInfo.Decl = builtinDecl;
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    result.BuiltinInfo.ID = builtinID;
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    return result;
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  }
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  static CGCallee forPseudoDestructor(const CXXPseudoDestructorExpr *E) {
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    CGCallee result(SpecialKind::PseudoDestructor);
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    result.PseudoDestructorInfo.Expr = E;
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    return result;
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  }
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  static CGCallee forDirect(llvm::Constant *functionPtr,
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                            const CGCalleeInfo &abstractInfo = CGCalleeInfo()) {
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    return CGCallee(abstractInfo, functionPtr);
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  }
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  static CGCallee forDirect(llvm::FunctionCallee functionPtr,
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                            const CGCalleeInfo &abstractInfo = CGCalleeInfo()) {
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    return CGCallee(abstractInfo, functionPtr.getCallee());
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  }
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  static CGCallee forVirtual(const CallExpr *CE, GlobalDecl MD, Address Addr,
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                             llvm::FunctionType *FTy) {
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    CGCallee result(SpecialKind::Virtual);
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    result.VirtualInfo.CE = CE;
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    result.VirtualInfo.MD = MD;
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    result.VirtualInfo.Addr = Addr;
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    result.VirtualInfo.FTy = FTy;
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    return result;
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  }
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  bool isBuiltin() const {
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    return KindOrFunctionPointer == SpecialKind::Builtin;
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  }
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  const FunctionDecl *getBuiltinDecl() const {
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    assert(isBuiltin());
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    return BuiltinInfo.Decl;
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  }
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  unsigned getBuiltinID() const {
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    assert(isBuiltin());
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    return BuiltinInfo.ID;
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  }
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  bool isPseudoDestructor() const {
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    return KindOrFunctionPointer == SpecialKind::PseudoDestructor;
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  }
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  const CXXPseudoDestructorExpr *getPseudoDestructorExpr() const {
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    assert(isPseudoDestructor());
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    return PseudoDestructorInfo.Expr;
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  }
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  bool isOrdinary() const {
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    return uintptr_t(KindOrFunctionPointer) > uintptr_t(SpecialKind::Last);
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  }
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797k
  CGCalleeInfo getAbstractInfo() const {
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    if (isVirtual())
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      return VirtualInfo.MD;
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    assert(isOrdinary());
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    return AbstractInfo;
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  }
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  llvm::Value *getFunctionPointer() const {
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    assert(isOrdinary());
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    return reinterpret_cast<llvm::Value *>(uintptr_t(KindOrFunctionPointer));
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  }
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  void setFunctionPointer(llvm::Value *functionPtr) {
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    assert(isOrdinary());
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    KindOrFunctionPointer = SpecialKind(uintptr_t(functionPtr));
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  }
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  bool isVirtual() const {
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    return KindOrFunctionPointer == SpecialKind::Virtual;
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  }
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  const CallExpr *getVirtualCallExpr() const {
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    assert(isVirtual());
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    return VirtualInfo.CE;
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  }
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  GlobalDecl getVirtualMethodDecl() const {
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    assert(isVirtual());
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    return VirtualInfo.MD;
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  }
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  Address getThisAddress() const {
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    assert(isVirtual());
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    return VirtualInfo.Addr;
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  }
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  llvm::FunctionType *getVirtualFunctionType() const {
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    assert(isVirtual());
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    return VirtualInfo.FTy;
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  }
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  /// If this is a delayed callee computation of some sort, prepare
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  /// a concrete callee.
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  CGCallee prepareConcreteCallee(CodeGenFunction &CGF) const;
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};
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struct CallArg {
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private:
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  union {
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    RValue RV;
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    LValue LV; /// The argument is semantically a load from this l-value.
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  };
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  bool HasLV;
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  /// A data-flow flag to make sure getRValue and/or copyInto are not
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  /// called twice for duplicated IR emission.
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  mutable bool IsUsed;
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public:
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  QualType Ty;
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  CallArg(RValue rv, QualType ty)
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      : RV(rv), HasLV(false), IsUsed(false), Ty(ty) {}
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  CallArg(LValue lv, QualType ty)
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      : LV(lv), HasLV(true), IsUsed(false), Ty(ty) {}
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  bool hasLValue() const { return HasLV; }
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  QualType getType() const { return Ty; }
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  /// \returns an independent RValue. If the CallArg contains an LValue,
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  /// a temporary copy is returned.
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  RValue getRValue(CodeGenFunction &CGF) const;
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  LValue getKnownLValue() const {
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    assert(HasLV && !IsUsed);
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    return LV;
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  }
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  RValue getKnownRValue() const {
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    assert(!HasLV && !IsUsed);
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    return RV;
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  }
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  void setRValue(RValue _RV) {
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    assert(!HasLV);
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    RV = _RV;
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  }
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  bool isAggregate() const { return HasLV || 
RV.isAggregate()529k
; }
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  void copyInto(CodeGenFunction &CGF, Address A) const;
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};
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/// CallArgList - Type for representing both the value and type of
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/// arguments in a call.
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class CallArgList : public SmallVector<CallArg, 8> {
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public:
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  CallArgList() : StackBase(nullptr) {}
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  struct Writeback {
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    /// The original argument.  Note that the argument l-value
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    /// is potentially null.
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    LValue Source;
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    /// The temporary alloca.
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    Address Temporary;
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    /// A value to "use" after the writeback, or null.
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    llvm::Value *ToUse;
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  };
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  struct CallArgCleanup {
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    EHScopeStack::stable_iterator Cleanup;
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    /// The "is active" insertion point.  This instruction is temporary and
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    /// will be removed after insertion.
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    llvm::Instruction *IsActiveIP;
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  };
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  void add(RValue rvalue, QualType type) { push_back(CallArg(rvalue, type)); }
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  void addUncopiedAggregate(LValue LV, QualType type) {
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    push_back(CallArg(LV, type));
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  }
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  /// Add all the arguments from another CallArgList to this one. After doing
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  /// this, the old CallArgList retains its list of arguments, but must not
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  /// be used to emit a call.
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13.0k
  void addFrom(const CallArgList &other) {
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    insert(end(), other.begin(), other.end());
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    Writebacks.insert(Writebacks.end(), other.Writebacks.begin(),
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13.0k
                      other.Writebacks.end());
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    CleanupsToDeactivate.insert(CleanupsToDeactivate.end(),
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                                other.CleanupsToDeactivate.begin(),
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                                other.CleanupsToDeactivate.end());
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    assert(!(StackBase && other.StackBase) && "can't merge stackbases");
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    if (!StackBase)
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      StackBase = other.StackBase;
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  }
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  void addWriteback(LValue srcLV, Address temporary, llvm::Value *toUse) {
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    Writeback writeback = {srcLV, temporary, toUse};
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    Writebacks.push_back(writeback);
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  }
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  bool hasWritebacks() const { return !Writebacks.empty(); }
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  typedef llvm::iterator_range<SmallVectorImpl<Writeback>::const_iterator>
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      writeback_const_range;
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  writeback_const_range writebacks() const {
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    return writeback_const_range(Writebacks.begin(), Writebacks.end());
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  }
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  void addArgCleanupDeactivation(EHScopeStack::stable_iterator Cleanup,
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                                 llvm::Instruction *IsActiveIP) {
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    CallArgCleanup ArgCleanup;
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    ArgCleanup.Cleanup = Cleanup;
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    ArgCleanup.IsActiveIP = IsActiveIP;
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    CleanupsToDeactivate.push_back(ArgCleanup);
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  }
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  ArrayRef<CallArgCleanup> getCleanupsToDeactivate() const {
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    return CleanupsToDeactivate;
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  }
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  void allocateArgumentMemory(CodeGenFunction &CGF);
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  llvm::Instruction *getStackBase() const { return StackBase; }
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  void freeArgumentMemory(CodeGenFunction &CGF) const;
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  /// Returns if we're using an inalloca struct to pass arguments in
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  /// memory.
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  bool isUsingInAlloca() const { return StackBase; }
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private:
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  SmallVector<Writeback, 1> Writebacks;
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  /// Deactivate these cleanups immediately before making the call.  This
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  /// is used to cleanup objects that are owned by the callee once the call
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  /// occurs.
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  SmallVector<CallArgCleanup, 1> CleanupsToDeactivate;
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  /// The stacksave call.  It dominates all of the argument evaluation.
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  llvm::CallInst *StackBase;
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};
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/// FunctionArgList - Type for representing both the decl and type
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/// of parameters to a function. The decl must be either a
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/// ParmVarDecl or ImplicitParamDecl.
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class FunctionArgList : public SmallVector<const VarDecl *, 16> {};
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/// ReturnValueSlot - Contains the address where the return value of a
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/// function can be stored, and whether the address is volatile or not.
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class ReturnValueSlot {
361
  Address Addr = Address::invalid();
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  // Return value slot flags
364
  unsigned IsVolatile : 1;
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  unsigned IsUnused : 1;
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  unsigned IsExternallyDestructed : 1;
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public:
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  ReturnValueSlot()
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378k
      : IsVolatile(false), IsUnused(false), IsExternallyDestructed(false) {}
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  ReturnValueSlot(Address Addr, bool IsVolatile, bool IsUnused = false,
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                  bool IsExternallyDestructed = false)
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      : Addr(Addr), IsVolatile(IsVolatile), IsUnused(IsUnused),
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6.69k
        IsExternallyDestructed(IsExternallyDestructed) {}
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2.31k
  bool isNull() const { return !Addr.isValid(); }
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5.02k
  bool isVolatile() const { return IsVolatile; }
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6.66k
  Address getValue() const { return Addr; }
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12.4k
  bool isUnused() const { return IsUnused; }
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318k
  bool isExternallyDestructed() const { return IsExternallyDestructed; }
381
};
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} // end namespace CodeGen
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} // end namespace clang
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#endif