544 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			544 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===--- CGDeclCXX.cpp - Emit LLVM Code for C++ declarations --------------===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // This contains code dealing with code generation of C++ declarations
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "CodeGenFunction.h"
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| #include "CGCXXABI.h"
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| #include "CGObjCRuntime.h"
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| #include "clang/Frontend/CodeGenOptions.h"
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| #include "llvm/ADT/StringExtras.h"
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| #include "llvm/IR/Intrinsics.h"
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| #include "llvm/Support/Path.h"
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| 
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| using namespace clang;
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| using namespace CodeGen;
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| 
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| static void EmitDeclInit(CodeGenFunction &CGF, const VarDecl &D,
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|                          llvm::Constant *DeclPtr) {
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|   assert(D.hasGlobalStorage() && "VarDecl must have global storage!");
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|   assert(!D.getType()->isReferenceType() && 
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|          "Should not call EmitDeclInit on a reference!");
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|   
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|   ASTContext &Context = CGF.getContext();
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| 
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|   CharUnits alignment = Context.getDeclAlign(&D);
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|   QualType type = D.getType();
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|   LValue lv = CGF.MakeAddrLValue(DeclPtr, type, alignment);
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| 
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|   const Expr *Init = D.getInit();
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|   switch (CGF.getEvaluationKind(type)) {
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|   case TEK_Scalar: {
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|     CodeGenModule &CGM = CGF.CGM;
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|     if (lv.isObjCStrong())
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|       CGM.getObjCRuntime().EmitObjCGlobalAssign(CGF, CGF.EmitScalarExpr(Init),
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|                                                 DeclPtr, D.getTLSKind());
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|     else if (lv.isObjCWeak())
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|       CGM.getObjCRuntime().EmitObjCWeakAssign(CGF, CGF.EmitScalarExpr(Init),
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|                                               DeclPtr);
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|     else
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|       CGF.EmitScalarInit(Init, &D, lv, false);
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|     return;
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|   }
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|   case TEK_Complex:
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|     CGF.EmitComplexExprIntoLValue(Init, lv, /*isInit*/ true);
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|     return;
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|   case TEK_Aggregate:
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|     CGF.EmitAggExpr(Init, AggValueSlot::forLValue(lv,AggValueSlot::IsDestructed,
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|                                           AggValueSlot::DoesNotNeedGCBarriers,
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|                                                   AggValueSlot::IsNotAliased));
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|     return;
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|   }
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|   llvm_unreachable("bad evaluation kind");
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| }
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| 
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| /// Emit code to cause the destruction of the given variable with
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| /// static storage duration.
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| static void EmitDeclDestroy(CodeGenFunction &CGF, const VarDecl &D,
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|                             llvm::Constant *addr) {
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|   CodeGenModule &CGM = CGF.CGM;
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| 
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|   // FIXME:  __attribute__((cleanup)) ?
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|   
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|   QualType type = D.getType();
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|   QualType::DestructionKind dtorKind = type.isDestructedType();
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| 
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|   switch (dtorKind) {
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|   case QualType::DK_none:
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|     return;
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| 
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|   case QualType::DK_cxx_destructor:
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|     break;
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| 
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|   case QualType::DK_objc_strong_lifetime:
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|   case QualType::DK_objc_weak_lifetime:
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|     // We don't care about releasing objects during process teardown.
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|     assert(!D.getTLSKind() && "should have rejected this");
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|     return;
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|   }
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| 
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|   llvm::Constant *function;
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|   llvm::Constant *argument;
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| 
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|   // Special-case non-array C++ destructors, where there's a function
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|   // with the right signature that we can just call.
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|   const CXXRecordDecl *record = nullptr;
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|   if (dtorKind == QualType::DK_cxx_destructor &&
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|       (record = type->getAsCXXRecordDecl())) {
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|     assert(!record->hasTrivialDestructor());
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|     CXXDestructorDecl *dtor = record->getDestructor();
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| 
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|     function = CGM.GetAddrOfCXXDestructor(dtor, Dtor_Complete);
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|     argument = llvm::ConstantExpr::getBitCast(
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|         addr, CGF.getTypes().ConvertType(type)->getPointerTo());
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| 
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|   // Otherwise, the standard logic requires a helper function.
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|   } else {
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|     function = CodeGenFunction(CGM)
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|         .generateDestroyHelper(addr, type, CGF.getDestroyer(dtorKind),
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|                                CGF.needsEHCleanup(dtorKind), &D);
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|     argument = llvm::Constant::getNullValue(CGF.Int8PtrTy);
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|   }
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| 
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|   CGM.getCXXABI().registerGlobalDtor(CGF, D, function, argument);
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| }
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| 
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| /// Emit code to cause the variable at the given address to be considered as
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| /// constant from this point onwards.
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| static void EmitDeclInvariant(CodeGenFunction &CGF, const VarDecl &D,
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|                               llvm::Constant *Addr) {
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|   // Don't emit the intrinsic if we're not optimizing.
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|   if (!CGF.CGM.getCodeGenOpts().OptimizationLevel)
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|     return;
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| 
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|   // Grab the llvm.invariant.start intrinsic.
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|   llvm::Intrinsic::ID InvStartID = llvm::Intrinsic::invariant_start;
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|   llvm::Constant *InvariantStart = CGF.CGM.getIntrinsic(InvStartID);
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| 
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|   // Emit a call with the size in bytes of the object.
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|   CharUnits WidthChars = CGF.getContext().getTypeSizeInChars(D.getType());
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|   uint64_t Width = WidthChars.getQuantity();
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|   llvm::Value *Args[2] = { llvm::ConstantInt::getSigned(CGF.Int64Ty, Width),
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|                            llvm::ConstantExpr::getBitCast(Addr, CGF.Int8PtrTy)};
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|   CGF.Builder.CreateCall(InvariantStart, Args);
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| }
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| 
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| void CodeGenFunction::EmitCXXGlobalVarDeclInit(const VarDecl &D,
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|                                                llvm::Constant *DeclPtr,
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|                                                bool PerformInit) {
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| 
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|   const Expr *Init = D.getInit();
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|   QualType T = D.getType();
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| 
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|   if (!T->isReferenceType()) {
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|     if (PerformInit)
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|       EmitDeclInit(*this, D, DeclPtr);
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|     if (CGM.isTypeConstant(D.getType(), true))
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|       EmitDeclInvariant(*this, D, DeclPtr);
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|     else
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|       EmitDeclDestroy(*this, D, DeclPtr);
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|     return;
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|   }
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| 
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|   assert(PerformInit && "cannot have constant initializer which needs "
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|          "destruction for reference");
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|   unsigned Alignment = getContext().getDeclAlign(&D).getQuantity();
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|   RValue RV = EmitReferenceBindingToExpr(Init);
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|   EmitStoreOfScalar(RV.getScalarVal(), DeclPtr, false, Alignment, T);
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| }
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| 
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| static llvm::Function *
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| CreateGlobalInitOrDestructFunction(CodeGenModule &CGM,
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|                                    llvm::FunctionType *ty,
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|                                    const Twine &name,
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|                                    bool TLS = false);
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| 
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| /// Create a stub function, suitable for being passed to atexit,
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| /// which passes the given address to the given destructor function.
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| static llvm::Constant *createAtExitStub(CodeGenModule &CGM, const VarDecl &VD,
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|                                         llvm::Constant *dtor,
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|                                         llvm::Constant *addr) {
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|   // Get the destructor function type, void(*)(void).
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|   llvm::FunctionType *ty = llvm::FunctionType::get(CGM.VoidTy, false);
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|   SmallString<256> FnName;
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|   {
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|     llvm::raw_svector_ostream Out(FnName);
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|     CGM.getCXXABI().getMangleContext().mangleDynamicAtExitDestructor(&VD, Out);
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|   }
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|   llvm::Function *fn =
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|       CreateGlobalInitOrDestructFunction(CGM, ty, FnName.str());
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| 
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|   CodeGenFunction CGF(CGM);
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| 
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|   CGF.StartFunction(&VD, CGM.getContext().VoidTy, fn,
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|                     CGM.getTypes().arrangeNullaryFunction(), FunctionArgList());
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| 
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|   llvm::CallInst *call = CGF.Builder.CreateCall(dtor, addr);
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|  
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|  // Make sure the call and the callee agree on calling convention.
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|   if (llvm::Function *dtorFn =
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|         dyn_cast<llvm::Function>(dtor->stripPointerCasts()))
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|     call->setCallingConv(dtorFn->getCallingConv());
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| 
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|   CGF.FinishFunction();
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| 
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|   return fn;
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| }
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| 
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| /// Register a global destructor using the C atexit runtime function.
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| void CodeGenFunction::registerGlobalDtorWithAtExit(const VarDecl &VD,
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|                                                    llvm::Constant *dtor,
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|                                                    llvm::Constant *addr) {
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|   // Create a function which calls the destructor.
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|   llvm::Constant *dtorStub = createAtExitStub(CGM, VD, dtor, addr);
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| 
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|   // extern "C" int atexit(void (*f)(void));
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|   llvm::FunctionType *atexitTy =
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|     llvm::FunctionType::get(IntTy, dtorStub->getType(), false);
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| 
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|   llvm::Constant *atexit =
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|     CGM.CreateRuntimeFunction(atexitTy, "atexit");
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|   if (llvm::Function *atexitFn = dyn_cast<llvm::Function>(atexit))
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|     atexitFn->setDoesNotThrow();
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| 
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|   EmitNounwindRuntimeCall(atexit, dtorStub);
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| }
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| 
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| void CodeGenFunction::EmitCXXGuardedInit(const VarDecl &D,
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|                                          llvm::GlobalVariable *DeclPtr,
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|                                          bool PerformInit) {
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|   // If we've been asked to forbid guard variables, emit an error now.
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|   // This diagnostic is hard-coded for Darwin's use case;  we can find
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|   // better phrasing if someone else needs it.
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|   if (CGM.getCodeGenOpts().ForbidGuardVariables)
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|     CGM.Error(D.getLocation(),
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|               "this initialization requires a guard variable, which "
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|               "the kernel does not support");
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| 
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|   CGM.getCXXABI().EmitGuardedInit(*this, D, DeclPtr, PerformInit);
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| }
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| 
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| static llvm::Function *
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| CreateGlobalInitOrDestructFunction(CodeGenModule &CGM,
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|                                    llvm::FunctionType *FTy,
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|                                    const Twine &Name, bool TLS) {
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|   llvm::Function *Fn =
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|     llvm::Function::Create(FTy, llvm::GlobalValue::InternalLinkage,
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|                            Name, &CGM.getModule());
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|   if (!CGM.getLangOpts().AppleKext && !TLS) {
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|     // Set the section if needed.
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|     if (const char *Section = 
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|           CGM.getTarget().getStaticInitSectionSpecifier())
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|       Fn->setSection(Section);
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|   }
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| 
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|   Fn->setCallingConv(CGM.getRuntimeCC());
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| 
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|   if (!CGM.getLangOpts().Exceptions)
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|     Fn->setDoesNotThrow();
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| 
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|   if (CGM.getSanOpts().Address)
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|     Fn->addFnAttr(llvm::Attribute::SanitizeAddress);
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|   if (CGM.getSanOpts().Thread)
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|     Fn->addFnAttr(llvm::Attribute::SanitizeThread);
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|   if (CGM.getSanOpts().Memory)
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|     Fn->addFnAttr(llvm::Attribute::SanitizeMemory);
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| 
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|   return Fn;
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| }
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| 
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| void
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| CodeGenModule::EmitCXXGlobalVarDeclInitFunc(const VarDecl *D,
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|                                             llvm::GlobalVariable *Addr,
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|                                             bool PerformInit) {
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|   llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false);
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|   SmallString<256> FnName;
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|   {
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|     llvm::raw_svector_ostream Out(FnName);
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|     getCXXABI().getMangleContext().mangleDynamicInitializer(D, Out);
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|   }
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| 
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|   // Create a variable initialization function.
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|   llvm::Function *Fn =
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|       CreateGlobalInitOrDestructFunction(*this, FTy, FnName.str());
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| 
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|   CodeGenFunction(*this).GenerateCXXGlobalVarDeclInitFunc(Fn, D, Addr,
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|                                                           PerformInit);
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| 
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|   if (D->getTLSKind()) {
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|     // FIXME: Should we support init_priority for thread_local?
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|     // FIXME: Ideally, initialization of instantiated thread_local static data
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|     // members of class templates should not trigger initialization of other
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|     // entities in the TU.
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|     // FIXME: We only need to register one __cxa_thread_atexit function for the
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|     // entire TU.
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|     CXXThreadLocalInits.push_back(Fn);
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|   } else if (const InitPriorityAttr *IPA = D->getAttr<InitPriorityAttr>()) {
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|     OrderGlobalInits Key(IPA->getPriority(), PrioritizedCXXGlobalInits.size());
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|     PrioritizedCXXGlobalInits.push_back(std::make_pair(Key, Fn));
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|     DelayedCXXInitPosition.erase(D);
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|   } else if (D->getTemplateSpecializationKind() != TSK_ExplicitSpecialization &&
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|              D->getTemplateSpecializationKind() != TSK_Undeclared) {
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|     // C++ [basic.start.init]p2:
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|     //   Definitions of explicitly specialized class template static data
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|     //   members have ordered initialization. Other class template static data
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|     //   members (i.e., implicitly or explicitly instantiated specializations)
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|     //   have unordered initialization.
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|     //
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|     // As a consequence, we can put them into their own llvm.global_ctors entry.
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|     //
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|     // In addition, put the initializer into a COMDAT group with the global
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|     // being initialized.  On most platforms, this is a minor startup time
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|     // optimization.  In the MS C++ ABI, there are no guard variables, so this
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|     // COMDAT key is required for correctness.
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|     AddGlobalCtor(Fn, 65535, Addr);
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|     DelayedCXXInitPosition.erase(D);
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|   } else {
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|     llvm::DenseMap<const Decl *, unsigned>::iterator I =
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|       DelayedCXXInitPosition.find(D);
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|     if (I == DelayedCXXInitPosition.end()) {
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|       CXXGlobalInits.push_back(Fn);
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|     } else {
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|       assert(CXXGlobalInits[I->second] == nullptr);
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|       CXXGlobalInits[I->second] = Fn;
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|       DelayedCXXInitPosition.erase(I);
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|     }
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|   }
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| }
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| 
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| void CodeGenModule::EmitCXXThreadLocalInitFunc() {
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|   llvm::Function *InitFn = nullptr;
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|   if (!CXXThreadLocalInits.empty()) {
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|     // Generate a guarded initialization function.
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|     llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false);
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|     InitFn = CreateGlobalInitOrDestructFunction(*this, FTy, "__tls_init",
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|                                                 /*TLS*/ true);
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|     llvm::GlobalVariable *Guard = new llvm::GlobalVariable(
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|         getModule(), Int8Ty, false, llvm::GlobalVariable::InternalLinkage,
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|         llvm::ConstantInt::get(Int8Ty, 0), "__tls_guard");
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|     Guard->setThreadLocal(true);
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|     CodeGenFunction(*this)
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|         .GenerateCXXGlobalInitFunc(InitFn, CXXThreadLocalInits, Guard);
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|   }
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| 
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|   getCXXABI().EmitThreadLocalInitFuncs(CXXThreadLocals, InitFn);
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| 
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|   CXXThreadLocalInits.clear();
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|   CXXThreadLocals.clear();
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| }
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| 
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| void
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| CodeGenModule::EmitCXXGlobalInitFunc() {
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|   while (!CXXGlobalInits.empty() && !CXXGlobalInits.back())
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|     CXXGlobalInits.pop_back();
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| 
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|   if (CXXGlobalInits.empty() && PrioritizedCXXGlobalInits.empty())
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|     return;
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| 
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|   llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false);
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| 
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| 
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|   // Create our global initialization function.
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|   if (!PrioritizedCXXGlobalInits.empty()) {
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|     SmallVector<llvm::Constant*, 8> LocalCXXGlobalInits;
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|     llvm::array_pod_sort(PrioritizedCXXGlobalInits.begin(), 
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|                          PrioritizedCXXGlobalInits.end());
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|     // Iterate over "chunks" of ctors with same priority and emit each chunk
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|     // into separate function. Note - everything is sorted first by priority,
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|     // second - by lex order, so we emit ctor functions in proper order.
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|     for (SmallVectorImpl<GlobalInitData >::iterator
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|            I = PrioritizedCXXGlobalInits.begin(),
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|            E = PrioritizedCXXGlobalInits.end(); I != E; ) {
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|       SmallVectorImpl<GlobalInitData >::iterator
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|         PrioE = std::upper_bound(I + 1, E, *I, GlobalInitPriorityCmp());
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| 
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|       LocalCXXGlobalInits.clear();
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|       unsigned Priority = I->first.priority;
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|       // Compute the function suffix from priority. Prepend with zeroes to make
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|       // sure the function names are also ordered as priorities.
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|       std::string PrioritySuffix = llvm::utostr(Priority);
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|       // Priority is always <= 65535 (enforced by sema).
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|       PrioritySuffix = std::string(6-PrioritySuffix.size(), '0')+PrioritySuffix;
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|       llvm::Function *Fn = 
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|         CreateGlobalInitOrDestructFunction(*this, FTy,
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|                                            "_GLOBAL__I_" + PrioritySuffix);
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|       
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|       for (; I < PrioE; ++I)
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|         LocalCXXGlobalInits.push_back(I->second);
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| 
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|       CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn, LocalCXXGlobalInits);
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|       AddGlobalCtor(Fn, Priority);
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|     }
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|   }
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|   
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|   // Include the filename in the symbol name. Including "sub_" matches gcc and
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|   // makes sure these symbols appear lexicographically behind the symbols with
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|   // priority emitted above.
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|   SourceManager &SM = Context.getSourceManager();
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|   SmallString<128> FileName(llvm::sys::path::filename(
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|       SM.getFileEntryForID(SM.getMainFileID())->getName()));
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|   for (size_t i = 0; i < FileName.size(); ++i) {
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|     // Replace everything that's not [a-zA-Z0-9._] with a _. This set happens
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|     // to be the set of C preprocessing numbers.
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|     if (!isPreprocessingNumberBody(FileName[i]))
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|       FileName[i] = '_';
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|   }
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|   llvm::Function *Fn = CreateGlobalInitOrDestructFunction(
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|       *this, FTy, llvm::Twine("_GLOBAL__sub_I_", FileName));
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| 
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|   CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn, CXXGlobalInits);
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|   AddGlobalCtor(Fn);
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| 
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|   CXXGlobalInits.clear();
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|   PrioritizedCXXGlobalInits.clear();
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| }
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| 
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| void CodeGenModule::EmitCXXGlobalDtorFunc() {
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|   if (CXXGlobalDtors.empty())
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|     return;
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| 
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|   llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false);
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| 
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|   // Create our global destructor function.
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|   llvm::Function *Fn =
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|     CreateGlobalInitOrDestructFunction(*this, FTy, "_GLOBAL__D_a");
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| 
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|   CodeGenFunction(*this).GenerateCXXGlobalDtorsFunc(Fn, CXXGlobalDtors);
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|   AddGlobalDtor(Fn);
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| }
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| 
 | |
| /// Emit the code necessary to initialize the given global variable.
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| void CodeGenFunction::GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
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|                                                        const VarDecl *D,
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|                                                  llvm::GlobalVariable *Addr,
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|                                                        bool PerformInit) {
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|   // Check if we need to emit debug info for variable initializer.
 | |
|   if (D->hasAttr<NoDebugAttr>())
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|     DebugInfo = nullptr; // disable debug info indefinitely for this function
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| 
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|   StartFunction(GlobalDecl(D), getContext().VoidTy, Fn,
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|                 getTypes().arrangeNullaryFunction(),
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|                 FunctionArgList(), D->getLocation(),
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|                 D->getInit()->getExprLoc());
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| 
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|   // Use guarded initialization if the global variable is weak. This
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|   // occurs for, e.g., instantiated static data members and
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|   // definitions explicitly marked weak.
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|   if (Addr->hasWeakLinkage() || Addr->hasLinkOnceLinkage()) {
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|     EmitCXXGuardedInit(*D, Addr, PerformInit);
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|   } else {
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|     EmitCXXGlobalVarDeclInit(*D, Addr, PerformInit);
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|   }
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| 
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|   FinishFunction();
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| }
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| 
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| void
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| CodeGenFunction::GenerateCXXGlobalInitFunc(llvm::Function *Fn,
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|                                            ArrayRef<llvm::Constant *> Decls,
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|                                            llvm::GlobalVariable *Guard) {
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|   {
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|     ArtificialLocation AL(*this, Builder);
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|     StartFunction(GlobalDecl(), getContext().VoidTy, Fn,
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|                   getTypes().arrangeNullaryFunction(), FunctionArgList());
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|     // Emit an artificial location for this function.
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|     AL.Emit();
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| 
 | |
|     llvm::BasicBlock *ExitBlock = nullptr;
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|     if (Guard) {
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|       // If we have a guard variable, check whether we've already performed
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|       // these initializations. This happens for TLS initialization functions.
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|       llvm::Value *GuardVal = Builder.CreateLoad(Guard);
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|       llvm::Value *Uninit = Builder.CreateIsNull(GuardVal,
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|                                                  "guard.uninitialized");
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|       // Mark as initialized before initializing anything else. If the
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|       // initializers use previously-initialized thread_local vars, that's
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|       // probably supposed to be OK, but the standard doesn't say.
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|       Builder.CreateStore(llvm::ConstantInt::get(GuardVal->getType(),1), Guard);
 | |
|       llvm::BasicBlock *InitBlock = createBasicBlock("init");
 | |
|       ExitBlock = createBasicBlock("exit");
 | |
|       Builder.CreateCondBr(Uninit, InitBlock, ExitBlock);
 | |
|       EmitBlock(InitBlock);
 | |
|     }
 | |
| 
 | |
|     RunCleanupsScope Scope(*this);
 | |
| 
 | |
|     // When building in Objective-C++ ARC mode, create an autorelease pool
 | |
|     // around the global initializers.
 | |
|     if (getLangOpts().ObjCAutoRefCount && getLangOpts().CPlusPlus) {
 | |
|       llvm::Value *token = EmitObjCAutoreleasePoolPush();
 | |
|       EmitObjCAutoreleasePoolCleanup(token);
 | |
|     }
 | |
| 
 | |
|     for (unsigned i = 0, e = Decls.size(); i != e; ++i)
 | |
|       if (Decls[i])
 | |
|         EmitRuntimeCall(Decls[i]);
 | |
| 
 | |
|     Scope.ForceCleanup();
 | |
| 
 | |
|     if (ExitBlock) {
 | |
|       Builder.CreateBr(ExitBlock);
 | |
|       EmitBlock(ExitBlock);
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   FinishFunction();
 | |
| }
 | |
| 
 | |
| void CodeGenFunction::GenerateCXXGlobalDtorsFunc(llvm::Function *Fn,
 | |
|                   const std::vector<std::pair<llvm::WeakVH, llvm::Constant*> >
 | |
|                                                 &DtorsAndObjects) {
 | |
|   {
 | |
|     ArtificialLocation AL(*this, Builder);
 | |
|     StartFunction(GlobalDecl(), getContext().VoidTy, Fn,
 | |
|                   getTypes().arrangeNullaryFunction(), FunctionArgList());
 | |
|     // Emit an artificial location for this function.
 | |
|     AL.Emit();
 | |
| 
 | |
|     // Emit the dtors, in reverse order from construction.
 | |
|     for (unsigned i = 0, e = DtorsAndObjects.size(); i != e; ++i) {
 | |
|       llvm::Value *Callee = DtorsAndObjects[e - i - 1].first;
 | |
|       llvm::CallInst *CI = Builder.CreateCall(Callee,
 | |
|                                           DtorsAndObjects[e - i - 1].second);
 | |
|       // Make sure the call and the callee agree on calling convention.
 | |
|       if (llvm::Function *F = dyn_cast<llvm::Function>(Callee))
 | |
|         CI->setCallingConv(F->getCallingConv());
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   FinishFunction();
 | |
| }
 | |
| 
 | |
| /// generateDestroyHelper - Generates a helper function which, when
 | |
| /// invoked, destroys the given object.
 | |
| llvm::Function *CodeGenFunction::generateDestroyHelper(
 | |
|     llvm::Constant *addr, QualType type, Destroyer *destroyer,
 | |
|     bool useEHCleanupForArray, const VarDecl *VD) {
 | |
|   FunctionArgList args;
 | |
|   ImplicitParamDecl dst(getContext(), nullptr, SourceLocation(), nullptr,
 | |
|                         getContext().VoidPtrTy);
 | |
|   args.push_back(&dst);
 | |
| 
 | |
|   const CGFunctionInfo &FI = CGM.getTypes().arrangeFreeFunctionDeclaration(
 | |
|       getContext().VoidTy, args, FunctionType::ExtInfo(), /*variadic=*/false);
 | |
|   llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(FI);
 | |
|   llvm::Function *fn = 
 | |
|     CreateGlobalInitOrDestructFunction(CGM, FTy, "__cxx_global_array_dtor");
 | |
| 
 | |
|   StartFunction(VD, getContext().VoidTy, fn, FI, args);
 | |
| 
 | |
|   emitDestroy(addr, type, destroyer, useEHCleanupForArray);
 | |
|   
 | |
|   FinishFunction();
 | |
|   
 | |
|   return fn;
 | |
| }
 |