607 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			607 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===- lib/Linker/LinkModules.cpp - Module Linker Implementation ----------===//
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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 file implements the LLVM module linker.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "LinkDiagnosticInfo.h"
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| #include "llvm-c/Linker.h"
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| #include "llvm/ADT/SetVector.h"
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| #include "llvm/IR/Comdat.h"
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| #include "llvm/IR/DiagnosticPrinter.h"
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| #include "llvm/IR/GlobalValue.h"
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| #include "llvm/IR/LLVMContext.h"
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| #include "llvm/IR/Module.h"
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| #include "llvm/Linker/Linker.h"
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| #include "llvm/Support/Error.h"
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| using namespace llvm;
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| 
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| namespace {
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| 
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| /// This is an implementation class for the LinkModules function, which is the
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| /// entrypoint for this file.
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| class ModuleLinker {
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|   IRMover &Mover;
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|   std::unique_ptr<Module> SrcM;
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| 
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|   SetVector<GlobalValue *> ValuesToLink;
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| 
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|   /// For symbol clashes, prefer those from Src.
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|   unsigned Flags;
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| 
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|   /// List of global value names that should be internalized.
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|   StringSet<> Internalize;
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| 
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|   /// Function that will perform the actual internalization. The reason for a
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|   /// callback is that the linker cannot call internalizeModule without
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|   /// creating a circular dependency between IPO and the linker.
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|   std::function<void(Module &, const StringSet<> &)> InternalizeCallback;
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| 
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|   /// Used as the callback for lazy linking.
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|   /// The mover has just hit GV and we have to decide if it, and other members
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|   /// of the same comdat, should be linked. Every member to be linked is passed
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|   /// to Add.
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|   void addLazyFor(GlobalValue &GV, const IRMover::ValueAdder &Add);
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| 
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|   bool shouldOverrideFromSrc() { return Flags & Linker::OverrideFromSrc; }
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|   bool shouldLinkOnlyNeeded() { return Flags & Linker::LinkOnlyNeeded; }
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| 
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|   bool shouldLinkFromSource(bool &LinkFromSrc, const GlobalValue &Dest,
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|                             const GlobalValue &Src);
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| 
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|   /// Should we have mover and linker error diag info?
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|   bool emitError(const Twine &Message) {
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|     SrcM->getContext().diagnose(LinkDiagnosticInfo(DS_Error, Message));
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|     return true;
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|   }
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| 
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|   bool getComdatLeader(Module &M, StringRef ComdatName,
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|                        const GlobalVariable *&GVar);
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|   bool computeResultingSelectionKind(StringRef ComdatName,
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|                                      Comdat::SelectionKind Src,
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|                                      Comdat::SelectionKind Dst,
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|                                      Comdat::SelectionKind &Result,
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|                                      bool &LinkFromSrc);
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|   std::map<const Comdat *, std::pair<Comdat::SelectionKind, bool>>
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|       ComdatsChosen;
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|   bool getComdatResult(const Comdat *SrcC, Comdat::SelectionKind &SK,
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|                        bool &LinkFromSrc);
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|   // Keep track of the lazy linked global members of each comdat in source.
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|   DenseMap<const Comdat *, std::vector<GlobalValue *>> LazyComdatMembers;
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| 
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|   /// Given a global in the source module, return the global in the
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|   /// destination module that is being linked to, if any.
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|   GlobalValue *getLinkedToGlobal(const GlobalValue *SrcGV) {
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|     Module &DstM = Mover.getModule();
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|     // If the source has no name it can't link.  If it has local linkage,
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|     // there is no name match-up going on.
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|     if (!SrcGV->hasName() || GlobalValue::isLocalLinkage(SrcGV->getLinkage()))
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|       return nullptr;
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| 
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|     // Otherwise see if we have a match in the destination module's symtab.
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|     GlobalValue *DGV = DstM.getNamedValue(SrcGV->getName());
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|     if (!DGV)
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|       return nullptr;
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| 
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|     // If we found a global with the same name in the dest module, but it has
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|     // internal linkage, we are really not doing any linkage here.
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|     if (DGV->hasLocalLinkage())
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|       return nullptr;
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| 
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|     // Otherwise, we do in fact link to the destination global.
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|     return DGV;
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|   }
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| 
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|   /// Drop GV if it is a member of a comdat that we are dropping.
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|   /// This can happen with COFF's largest selection kind.
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|   void dropReplacedComdat(GlobalValue &GV,
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|                           const DenseSet<const Comdat *> &ReplacedDstComdats);
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| 
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|   bool linkIfNeeded(GlobalValue &GV);
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| 
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| public:
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|   ModuleLinker(IRMover &Mover, std::unique_ptr<Module> SrcM, unsigned Flags,
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|                std::function<void(Module &, const StringSet<> &)>
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|                    InternalizeCallback = {})
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|       : Mover(Mover), SrcM(std::move(SrcM)), Flags(Flags),
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|         InternalizeCallback(std::move(InternalizeCallback)) {}
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| 
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|   bool run();
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| };
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| }
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| 
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| static GlobalValue::VisibilityTypes
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| getMinVisibility(GlobalValue::VisibilityTypes A,
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|                  GlobalValue::VisibilityTypes B) {
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|   if (A == GlobalValue::HiddenVisibility || B == GlobalValue::HiddenVisibility)
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|     return GlobalValue::HiddenVisibility;
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|   if (A == GlobalValue::ProtectedVisibility ||
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|       B == GlobalValue::ProtectedVisibility)
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|     return GlobalValue::ProtectedVisibility;
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|   return GlobalValue::DefaultVisibility;
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| }
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| 
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| bool ModuleLinker::getComdatLeader(Module &M, StringRef ComdatName,
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|                                    const GlobalVariable *&GVar) {
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|   const GlobalValue *GVal = M.getNamedValue(ComdatName);
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|   if (const auto *GA = dyn_cast_or_null<GlobalAlias>(GVal)) {
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|     GVal = GA->getBaseObject();
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|     if (!GVal)
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|       // We cannot resolve the size of the aliasee yet.
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|       return emitError("Linking COMDATs named '" + ComdatName +
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|                        "': COMDAT key involves incomputable alias size.");
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|   }
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| 
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|   GVar = dyn_cast_or_null<GlobalVariable>(GVal);
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|   if (!GVar)
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|     return emitError(
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|         "Linking COMDATs named '" + ComdatName +
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|         "': GlobalVariable required for data dependent selection!");
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| 
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|   return false;
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| }
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| 
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| bool ModuleLinker::computeResultingSelectionKind(StringRef ComdatName,
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|                                                  Comdat::SelectionKind Src,
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|                                                  Comdat::SelectionKind Dst,
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|                                                  Comdat::SelectionKind &Result,
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|                                                  bool &LinkFromSrc) {
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|   Module &DstM = Mover.getModule();
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|   // The ability to mix Comdat::SelectionKind::Any with
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|   // Comdat::SelectionKind::Largest is a behavior that comes from COFF.
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|   bool DstAnyOrLargest = Dst == Comdat::SelectionKind::Any ||
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|                          Dst == Comdat::SelectionKind::Largest;
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|   bool SrcAnyOrLargest = Src == Comdat::SelectionKind::Any ||
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|                          Src == Comdat::SelectionKind::Largest;
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|   if (DstAnyOrLargest && SrcAnyOrLargest) {
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|     if (Dst == Comdat::SelectionKind::Largest ||
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|         Src == Comdat::SelectionKind::Largest)
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|       Result = Comdat::SelectionKind::Largest;
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|     else
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|       Result = Comdat::SelectionKind::Any;
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|   } else if (Src == Dst) {
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|     Result = Dst;
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|   } else {
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|     return emitError("Linking COMDATs named '" + ComdatName +
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|                      "': invalid selection kinds!");
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|   }
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| 
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|   switch (Result) {
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|   case Comdat::SelectionKind::Any:
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|     // Go with Dst.
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|     LinkFromSrc = false;
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|     break;
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|   case Comdat::SelectionKind::NoDuplicates:
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|     return emitError("Linking COMDATs named '" + ComdatName +
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|                      "': noduplicates has been violated!");
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|   case Comdat::SelectionKind::ExactMatch:
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|   case Comdat::SelectionKind::Largest:
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|   case Comdat::SelectionKind::SameSize: {
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|     const GlobalVariable *DstGV;
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|     const GlobalVariable *SrcGV;
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|     if (getComdatLeader(DstM, ComdatName, DstGV) ||
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|         getComdatLeader(*SrcM, ComdatName, SrcGV))
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|       return true;
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| 
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|     const DataLayout &DstDL = DstM.getDataLayout();
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|     const DataLayout &SrcDL = SrcM->getDataLayout();
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|     uint64_t DstSize = DstDL.getTypeAllocSize(DstGV->getValueType());
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|     uint64_t SrcSize = SrcDL.getTypeAllocSize(SrcGV->getValueType());
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|     if (Result == Comdat::SelectionKind::ExactMatch) {
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|       if (SrcGV->getInitializer() != DstGV->getInitializer())
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|         return emitError("Linking COMDATs named '" + ComdatName +
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|                          "': ExactMatch violated!");
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|       LinkFromSrc = false;
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|     } else if (Result == Comdat::SelectionKind::Largest) {
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|       LinkFromSrc = SrcSize > DstSize;
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|     } else if (Result == Comdat::SelectionKind::SameSize) {
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|       if (SrcSize != DstSize)
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|         return emitError("Linking COMDATs named '" + ComdatName +
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|                          "': SameSize violated!");
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|       LinkFromSrc = false;
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|     } else {
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|       llvm_unreachable("unknown selection kind");
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|     }
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|     break;
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|   }
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|   }
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| 
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|   return false;
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| }
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| 
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| bool ModuleLinker::getComdatResult(const Comdat *SrcC,
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|                                    Comdat::SelectionKind &Result,
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|                                    bool &LinkFromSrc) {
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|   Module &DstM = Mover.getModule();
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|   Comdat::SelectionKind SSK = SrcC->getSelectionKind();
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|   StringRef ComdatName = SrcC->getName();
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|   Module::ComdatSymTabType &ComdatSymTab = DstM.getComdatSymbolTable();
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|   Module::ComdatSymTabType::iterator DstCI = ComdatSymTab.find(ComdatName);
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| 
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|   if (DstCI == ComdatSymTab.end()) {
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|     // Use the comdat if it is only available in one of the modules.
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|     LinkFromSrc = true;
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|     Result = SSK;
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|     return false;
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|   }
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| 
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|   const Comdat *DstC = &DstCI->second;
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|   Comdat::SelectionKind DSK = DstC->getSelectionKind();
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|   return computeResultingSelectionKind(ComdatName, SSK, DSK, Result,
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|                                        LinkFromSrc);
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| }
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| 
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| bool ModuleLinker::shouldLinkFromSource(bool &LinkFromSrc,
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|                                         const GlobalValue &Dest,
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|                                         const GlobalValue &Src) {
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| 
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|   // Should we unconditionally use the Src?
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|   if (shouldOverrideFromSrc()) {
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|     LinkFromSrc = true;
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|     return false;
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|   }
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| 
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|   // We always have to add Src if it has appending linkage.
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|   if (Src.hasAppendingLinkage()) {
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|     LinkFromSrc = true;
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|     return false;
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|   }
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| 
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|   bool SrcIsDeclaration = Src.isDeclarationForLinker();
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|   bool DestIsDeclaration = Dest.isDeclarationForLinker();
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| 
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|   if (SrcIsDeclaration) {
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|     // If Src is external or if both Src & Dest are external..  Just link the
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|     // external globals, we aren't adding anything.
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|     if (Src.hasDLLImportStorageClass()) {
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|       // If one of GVs is marked as DLLImport, result should be dllimport'ed.
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|       LinkFromSrc = DestIsDeclaration;
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|       return false;
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|     }
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|     // If the Dest is weak, use the source linkage.
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|     if (Dest.hasExternalWeakLinkage()) {
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|       LinkFromSrc = true;
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|       return false;
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|     }
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|     // Link an available_externally over a declaration.
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|     LinkFromSrc = !Src.isDeclaration() && Dest.isDeclaration();
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|     return false;
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|   }
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| 
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|   if (DestIsDeclaration) {
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|     // If Dest is external but Src is not:
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|     LinkFromSrc = true;
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|     return false;
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|   }
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| 
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|   if (Src.hasCommonLinkage()) {
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|     if (Dest.hasLinkOnceLinkage() || Dest.hasWeakLinkage()) {
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|       LinkFromSrc = true;
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|       return false;
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|     }
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| 
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|     if (!Dest.hasCommonLinkage()) {
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|       LinkFromSrc = false;
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|       return false;
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|     }
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| 
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|     const DataLayout &DL = Dest.getParent()->getDataLayout();
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|     uint64_t DestSize = DL.getTypeAllocSize(Dest.getValueType());
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|     uint64_t SrcSize = DL.getTypeAllocSize(Src.getValueType());
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|     LinkFromSrc = SrcSize > DestSize;
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|     return false;
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|   }
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| 
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|   if (Src.isWeakForLinker()) {
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|     assert(!Dest.hasExternalWeakLinkage());
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|     assert(!Dest.hasAvailableExternallyLinkage());
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| 
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|     if (Dest.hasLinkOnceLinkage() && Src.hasWeakLinkage()) {
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|       LinkFromSrc = true;
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|       return false;
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|     }
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| 
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|     LinkFromSrc = false;
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|     return false;
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|   }
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| 
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|   if (Dest.isWeakForLinker()) {
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|     assert(Src.hasExternalLinkage());
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|     LinkFromSrc = true;
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|     return false;
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|   }
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| 
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|   assert(!Src.hasExternalWeakLinkage());
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|   assert(!Dest.hasExternalWeakLinkage());
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|   assert(Dest.hasExternalLinkage() && Src.hasExternalLinkage() &&
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|          "Unexpected linkage type!");
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|   return emitError("Linking globals named '" + Src.getName() +
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|                    "': symbol multiply defined!");
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| }
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| 
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| bool ModuleLinker::linkIfNeeded(GlobalValue &GV) {
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|   GlobalValue *DGV = getLinkedToGlobal(&GV);
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| 
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|   if (shouldLinkOnlyNeeded()) {
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|     // Always import variables with appending linkage.
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|     if (!GV.hasAppendingLinkage()) {
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|       // Don't import globals unless they are referenced by the destination
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|       // module.
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|       if (!DGV)
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|         return false;
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|       // Don't import globals that are already defined in the destination module
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|       if (!DGV->isDeclaration())
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|         return false;
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|     }
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|   }
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| 
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|   if (DGV && !GV.hasLocalLinkage() && !GV.hasAppendingLinkage()) {
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|     auto *DGVar = dyn_cast<GlobalVariable>(DGV);
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|     auto *SGVar = dyn_cast<GlobalVariable>(&GV);
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|     if (DGVar && SGVar) {
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|       if (DGVar->isDeclaration() && SGVar->isDeclaration() &&
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|           (!DGVar->isConstant() || !SGVar->isConstant())) {
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|         DGVar->setConstant(false);
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|         SGVar->setConstant(false);
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|       }
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|       if (DGVar->hasCommonLinkage() && SGVar->hasCommonLinkage()) {
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|         unsigned Align = std::max(DGVar->getAlignment(), SGVar->getAlignment());
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|         SGVar->setAlignment(Align);
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|         DGVar->setAlignment(Align);
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|       }
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|     }
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| 
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|     GlobalValue::VisibilityTypes Visibility =
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|         getMinVisibility(DGV->getVisibility(), GV.getVisibility());
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|     DGV->setVisibility(Visibility);
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|     GV.setVisibility(Visibility);
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| 
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|     GlobalValue::UnnamedAddr UnnamedAddr = GlobalValue::getMinUnnamedAddr(
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|         DGV->getUnnamedAddr(), GV.getUnnamedAddr());
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|     DGV->setUnnamedAddr(UnnamedAddr);
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|     GV.setUnnamedAddr(UnnamedAddr);
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|   }
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| 
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|   if (!DGV && !shouldOverrideFromSrc() &&
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|       (GV.hasLocalLinkage() || GV.hasLinkOnceLinkage() ||
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|        GV.hasAvailableExternallyLinkage()))
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|     return false;
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| 
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|   if (GV.isDeclaration())
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|     return false;
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| 
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|   if (const Comdat *SC = GV.getComdat()) {
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|     bool LinkFromSrc;
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|     Comdat::SelectionKind SK;
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|     std::tie(SK, LinkFromSrc) = ComdatsChosen[SC];
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|     if (!LinkFromSrc)
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|       return false;
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|   }
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| 
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|   bool LinkFromSrc = true;
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|   if (DGV && shouldLinkFromSource(LinkFromSrc, *DGV, GV))
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|     return true;
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|   if (LinkFromSrc)
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|     ValuesToLink.insert(&GV);
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|   return false;
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| }
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| 
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| void ModuleLinker::addLazyFor(GlobalValue &GV, const IRMover::ValueAdder &Add) {
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|   // Add these to the internalize list
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|   if (!GV.hasLinkOnceLinkage() && !GV.hasAvailableExternallyLinkage() &&
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|       !shouldLinkOnlyNeeded())
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|     return;
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| 
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|   if (InternalizeCallback)
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|     Internalize.insert(GV.getName());
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|   Add(GV);
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| 
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|   const Comdat *SC = GV.getComdat();
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|   if (!SC)
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|     return;
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|   for (GlobalValue *GV2 : LazyComdatMembers[SC]) {
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|     GlobalValue *DGV = getLinkedToGlobal(GV2);
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|     bool LinkFromSrc = true;
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|     if (DGV && shouldLinkFromSource(LinkFromSrc, *DGV, *GV2))
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|       return;
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|     if (!LinkFromSrc)
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|       continue;
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|     if (InternalizeCallback)
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|       Internalize.insert(GV2->getName());
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|     Add(*GV2);
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|   }
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| }
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| 
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| void ModuleLinker::dropReplacedComdat(
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|     GlobalValue &GV, const DenseSet<const Comdat *> &ReplacedDstComdats) {
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|   Comdat *C = GV.getComdat();
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|   if (!C)
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|     return;
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|   if (!ReplacedDstComdats.count(C))
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|     return;
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|   if (GV.use_empty()) {
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|     GV.eraseFromParent();
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|     return;
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|   }
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| 
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|   if (auto *F = dyn_cast<Function>(&GV)) {
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|     F->deleteBody();
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|   } else if (auto *Var = dyn_cast<GlobalVariable>(&GV)) {
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|     Var->setInitializer(nullptr);
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|   } else {
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|     auto &Alias = cast<GlobalAlias>(GV);
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|     Module &M = *Alias.getParent();
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|     PointerType &Ty = *cast<PointerType>(Alias.getType());
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|     GlobalValue *Declaration;
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|     if (auto *FTy = dyn_cast<FunctionType>(Alias.getValueType())) {
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|       Declaration = Function::Create(FTy, GlobalValue::ExternalLinkage, "", &M);
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|     } else {
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|       Declaration =
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|           new GlobalVariable(M, Ty.getElementType(), /*isConstant*/ false,
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|                              GlobalValue::ExternalLinkage,
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|                              /*Initializer*/ nullptr);
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|     }
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|     Declaration->takeName(&Alias);
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|     Alias.replaceAllUsesWith(Declaration);
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|     Alias.eraseFromParent();
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|   }
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| }
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| 
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| bool ModuleLinker::run() {
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|   Module &DstM = Mover.getModule();
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|   DenseSet<const Comdat *> ReplacedDstComdats;
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| 
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|   for (const auto &SMEC : SrcM->getComdatSymbolTable()) {
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|     const Comdat &C = SMEC.getValue();
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|     if (ComdatsChosen.count(&C))
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|       continue;
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|     Comdat::SelectionKind SK;
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|     bool LinkFromSrc;
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|     if (getComdatResult(&C, SK, LinkFromSrc))
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|       return true;
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|     ComdatsChosen[&C] = std::make_pair(SK, LinkFromSrc);
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| 
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|     if (!LinkFromSrc)
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|       continue;
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| 
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|     Module::ComdatSymTabType &ComdatSymTab = DstM.getComdatSymbolTable();
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|     Module::ComdatSymTabType::iterator DstCI = ComdatSymTab.find(C.getName());
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|     if (DstCI == ComdatSymTab.end())
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|       continue;
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| 
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|     // The source comdat is replacing the dest one.
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|     const Comdat *DstC = &DstCI->second;
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|     ReplacedDstComdats.insert(DstC);
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|   }
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| 
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|   // Alias have to go first, since we are not able to find their comdats
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|   // otherwise.
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|   for (auto I = DstM.alias_begin(), E = DstM.alias_end(); I != E;) {
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|     GlobalAlias &GV = *I++;
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|     dropReplacedComdat(GV, ReplacedDstComdats);
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|   }
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| 
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|   for (auto I = DstM.global_begin(), E = DstM.global_end(); I != E;) {
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|     GlobalVariable &GV = *I++;
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|     dropReplacedComdat(GV, ReplacedDstComdats);
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|   }
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| 
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|   for (auto I = DstM.begin(), E = DstM.end(); I != E;) {
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|     Function &GV = *I++;
 | |
|     dropReplacedComdat(GV, ReplacedDstComdats);
 | |
|   }
 | |
| 
 | |
|   for (GlobalVariable &GV : SrcM->globals())
 | |
|     if (GV.hasLinkOnceLinkage())
 | |
|       if (const Comdat *SC = GV.getComdat())
 | |
|         LazyComdatMembers[SC].push_back(&GV);
 | |
| 
 | |
|   for (Function &SF : *SrcM)
 | |
|     if (SF.hasLinkOnceLinkage())
 | |
|       if (const Comdat *SC = SF.getComdat())
 | |
|         LazyComdatMembers[SC].push_back(&SF);
 | |
| 
 | |
|   for (GlobalAlias &GA : SrcM->aliases())
 | |
|     if (GA.hasLinkOnceLinkage())
 | |
|       if (const Comdat *SC = GA.getComdat())
 | |
|         LazyComdatMembers[SC].push_back(&GA);
 | |
| 
 | |
|   // Insert all of the globals in src into the DstM module... without linking
 | |
|   // initializers (which could refer to functions not yet mapped over).
 | |
|   for (GlobalVariable &GV : SrcM->globals())
 | |
|     if (linkIfNeeded(GV))
 | |
|       return true;
 | |
| 
 | |
|   for (Function &SF : *SrcM)
 | |
|     if (linkIfNeeded(SF))
 | |
|       return true;
 | |
| 
 | |
|   for (GlobalAlias &GA : SrcM->aliases())
 | |
|     if (linkIfNeeded(GA))
 | |
|       return true;
 | |
| 
 | |
|   for (unsigned I = 0; I < ValuesToLink.size(); ++I) {
 | |
|     GlobalValue *GV = ValuesToLink[I];
 | |
|     const Comdat *SC = GV->getComdat();
 | |
|     if (!SC)
 | |
|       continue;
 | |
|     for (GlobalValue *GV2 : LazyComdatMembers[SC]) {
 | |
|       GlobalValue *DGV = getLinkedToGlobal(GV2);
 | |
|       bool LinkFromSrc = true;
 | |
|       if (DGV && shouldLinkFromSource(LinkFromSrc, *DGV, *GV2))
 | |
|         return true;
 | |
|       if (LinkFromSrc)
 | |
|         ValuesToLink.insert(GV2);
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   if (InternalizeCallback) {
 | |
|     for (GlobalValue *GV : ValuesToLink)
 | |
|       Internalize.insert(GV->getName());
 | |
|   }
 | |
| 
 | |
|   // FIXME: Propagate Errors through to the caller instead of emitting
 | |
|   // diagnostics.
 | |
|   bool HasErrors = false;
 | |
|   if (Error E = Mover.move(std::move(SrcM), ValuesToLink.getArrayRef(),
 | |
|                            [this](GlobalValue &GV, IRMover::ValueAdder Add) {
 | |
|                              addLazyFor(GV, Add);
 | |
|                            },
 | |
|                            /* IsPerformingImport */ false)) {
 | |
|     handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
 | |
|       DstM.getContext().diagnose(LinkDiagnosticInfo(DS_Error, EIB.message()));
 | |
|       HasErrors = true;
 | |
|     });
 | |
|   }
 | |
|   if (HasErrors)
 | |
|     return true;
 | |
| 
 | |
|   if (InternalizeCallback)
 | |
|     InternalizeCallback(DstM, Internalize);
 | |
| 
 | |
|   return false;
 | |
| }
 | |
| 
 | |
| Linker::Linker(Module &M) : Mover(M) {}
 | |
| 
 | |
| bool Linker::linkInModule(
 | |
|     std::unique_ptr<Module> Src, unsigned Flags,
 | |
|     std::function<void(Module &, const StringSet<> &)> InternalizeCallback) {
 | |
|   ModuleLinker ModLinker(Mover, std::move(Src), Flags,
 | |
|                          std::move(InternalizeCallback));
 | |
|   return ModLinker.run();
 | |
| }
 | |
| 
 | |
| //===----------------------------------------------------------------------===//
 | |
| // LinkModules entrypoint.
 | |
| //===----------------------------------------------------------------------===//
 | |
| 
 | |
| /// This function links two modules together, with the resulting Dest module
 | |
| /// modified to be the composite of the two input modules. If an error occurs,
 | |
| /// true is returned and ErrorMsg (if not null) is set to indicate the problem.
 | |
| /// Upon failure, the Dest module could be in a modified state, and shouldn't be
 | |
| /// relied on to be consistent.
 | |
| bool Linker::linkModules(
 | |
|     Module &Dest, std::unique_ptr<Module> Src, unsigned Flags,
 | |
|     std::function<void(Module &, const StringSet<> &)> InternalizeCallback) {
 | |
|   Linker L(Dest);
 | |
|   return L.linkInModule(std::move(Src), Flags, std::move(InternalizeCallback));
 | |
| }
 | |
| 
 | |
| //===----------------------------------------------------------------------===//
 | |
| // C API.
 | |
| //===----------------------------------------------------------------------===//
 | |
| 
 | |
| LLVMBool LLVMLinkModules2(LLVMModuleRef Dest, LLVMModuleRef Src) {
 | |
|   Module *D = unwrap(Dest);
 | |
|   std::unique_ptr<Module> M(unwrap(Src));
 | |
|   return Linker::linkModules(*D, std::move(M));
 | |
| }
 |