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-rw-r--r--contrib/llvm/lib/Linker/LinkArchives.cpp197
-rw-r--r--contrib/llvm/lib/Linker/LinkItems.cpp241
-rw-r--r--contrib/llvm/lib/Linker/LinkModules.cpp1337
-rw-r--r--contrib/llvm/lib/Linker/Linker.cpp181
4 files changed, 1956 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Linker/LinkArchives.cpp b/contrib/llvm/lib/Linker/LinkArchives.cpp
new file mode 100644
index 0000000..c16d195
--- /dev/null
+++ b/contrib/llvm/lib/Linker/LinkArchives.cpp
@@ -0,0 +1,197 @@
+//===- lib/Linker/LinkArchives.cpp - Link LLVM objects and libraries ------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains routines to handle linking together LLVM bitcode files,
+// and to handle annoying things like static libraries.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Linker.h"
+#include "llvm/Module.h"
+#include "llvm/ADT/SetOperations.h"
+#include "llvm/Bitcode/Archive.h"
+#include <memory>
+#include <set>
+using namespace llvm;
+
+/// GetAllUndefinedSymbols - calculates the set of undefined symbols that still
+/// exist in an LLVM module. This is a bit tricky because there may be two
+/// symbols with the same name but different LLVM types that will be resolved to
+/// each other but aren't currently (thus we need to treat it as resolved).
+///
+/// Inputs:
+/// M - The module in which to find undefined symbols.
+///
+/// Outputs:
+/// UndefinedSymbols - A set of C++ strings containing the name of all
+/// undefined symbols.
+///
+static void
+GetAllUndefinedSymbols(Module *M, std::set<std::string> &UndefinedSymbols) {
+ std::set<std::string> DefinedSymbols;
+ UndefinedSymbols.clear();
+
+ // If the program doesn't define a main, try pulling one in from a .a file.
+ // This is needed for programs where the main function is defined in an
+ // archive, such f2c'd programs.
+ Function *Main = M->getFunction("main");
+ if (Main == 0 || Main->isDeclaration())
+ UndefinedSymbols.insert("main");
+
+ for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
+ if (I->hasName()) {
+ if (I->isDeclaration())
+ UndefinedSymbols.insert(I->getName());
+ else if (!I->hasLocalLinkage()) {
+ assert(!I->hasDLLImportLinkage()
+ && "Found dllimported non-external symbol!");
+ DefinedSymbols.insert(I->getName());
+ }
+ }
+
+ for (Module::global_iterator I = M->global_begin(), E = M->global_end();
+ I != E; ++I)
+ if (I->hasName()) {
+ if (I->isDeclaration())
+ UndefinedSymbols.insert(I->getName());
+ else if (!I->hasLocalLinkage()) {
+ assert(!I->hasDLLImportLinkage()
+ && "Found dllimported non-external symbol!");
+ DefinedSymbols.insert(I->getName());
+ }
+ }
+
+ for (Module::alias_iterator I = M->alias_begin(), E = M->alias_end();
+ I != E; ++I)
+ if (I->hasName())
+ DefinedSymbols.insert(I->getName());
+
+ // Prune out any defined symbols from the undefined symbols set...
+ for (std::set<std::string>::iterator I = UndefinedSymbols.begin();
+ I != UndefinedSymbols.end(); )
+ if (DefinedSymbols.count(*I))
+ UndefinedSymbols.erase(I++); // This symbol really is defined!
+ else
+ ++I; // Keep this symbol in the undefined symbols list
+}
+
+/// LinkInArchive - opens an archive library and link in all objects which
+/// provide symbols that are currently undefined.
+///
+/// Inputs:
+/// Filename - The pathname of the archive.
+///
+/// Return Value:
+/// TRUE - An error occurred.
+/// FALSE - No errors.
+bool
+Linker::LinkInArchive(const sys::Path &Filename, bool &is_native) {
+ // Make sure this is an archive file we're dealing with
+ if (!Filename.isArchive())
+ return error("File '" + Filename.str() + "' is not an archive.");
+
+ // Open the archive file
+ verbose("Linking archive file '" + Filename.str() + "'");
+
+ // Find all of the symbols currently undefined in the bitcode program.
+ // If all the symbols are defined, the program is complete, and there is
+ // no reason to link in any archive files.
+ std::set<std::string> UndefinedSymbols;
+ GetAllUndefinedSymbols(Composite, UndefinedSymbols);
+
+ if (UndefinedSymbols.empty()) {
+ verbose("No symbols undefined, skipping library '" + Filename.str() + "'");
+ return false; // No need to link anything in!
+ }
+
+ std::string ErrMsg;
+ std::auto_ptr<Archive> AutoArch (
+ Archive::OpenAndLoadSymbols(Filename, Context, &ErrMsg));
+
+ Archive* arch = AutoArch.get();
+
+ if (!arch)
+ return error("Cannot read archive '" + Filename.str() +
+ "': " + ErrMsg);
+ if (!arch->isBitcodeArchive()) {
+ is_native = true;
+ return false;
+ }
+ is_native = false;
+
+ // Save a set of symbols that are not defined by the archive. Since we're
+ // entering a loop, there's no point searching for these multiple times. This
+ // variable is used to "set_subtract" from the set of undefined symbols.
+ std::set<std::string> NotDefinedByArchive;
+
+ // Save the current set of undefined symbols, because we may have to make
+ // multiple passes over the archive:
+ std::set<std::string> CurrentlyUndefinedSymbols;
+
+ do {
+ CurrentlyUndefinedSymbols = UndefinedSymbols;
+
+ // Find the modules we need to link into the target module. Note that arch
+ // keeps ownership of these modules and may return the same Module* from a
+ // subsequent call.
+ SmallVector<Module*, 16> Modules;
+ if (!arch->findModulesDefiningSymbols(UndefinedSymbols, Modules, &ErrMsg))
+ return error("Cannot find symbols in '" + Filename.str() +
+ "': " + ErrMsg);
+
+ // If we didn't find any more modules to link this time, we are done
+ // searching this archive.
+ if (Modules.empty())
+ break;
+
+ // Any symbols remaining in UndefinedSymbols after
+ // findModulesDefiningSymbols are ones that the archive does not define. So
+ // we add them to the NotDefinedByArchive variable now.
+ NotDefinedByArchive.insert(UndefinedSymbols.begin(),
+ UndefinedSymbols.end());
+
+ // Loop over all the Modules that we got back from the archive
+ for (SmallVectorImpl<Module*>::iterator I=Modules.begin(), E=Modules.end();
+ I != E; ++I) {
+
+ // Get the module we must link in.
+ std::string moduleErrorMsg;
+ Module* aModule = *I;
+ if (aModule != NULL) {
+ if (aModule->MaterializeAll(&moduleErrorMsg))
+ return error("Could not load a module: " + moduleErrorMsg);
+
+ verbose(" Linking in module: " + aModule->getModuleIdentifier());
+
+ // Link it in
+ if (LinkInModule(aModule, &moduleErrorMsg))
+ return error("Cannot link in module '" +
+ aModule->getModuleIdentifier() + "': " + moduleErrorMsg);
+ }
+ }
+
+ // Get the undefined symbols from the aggregate module. This recomputes the
+ // symbols we still need after the new modules have been linked in.
+ GetAllUndefinedSymbols(Composite, UndefinedSymbols);
+
+ // At this point we have two sets of undefined symbols: UndefinedSymbols
+ // which holds the undefined symbols from all the modules, and
+ // NotDefinedByArchive which holds symbols we know the archive doesn't
+ // define. There's no point searching for symbols that we won't find in the
+ // archive so we subtract these sets.
+ set_subtract(UndefinedSymbols, NotDefinedByArchive);
+
+ // If there's no symbols left, no point in continuing to search the
+ // archive.
+ if (UndefinedSymbols.empty())
+ break;
+ } while (CurrentlyUndefinedSymbols != UndefinedSymbols);
+
+ return false;
+}
diff --git a/contrib/llvm/lib/Linker/LinkItems.cpp b/contrib/llvm/lib/Linker/LinkItems.cpp
new file mode 100644
index 0000000..52a0d17
--- /dev/null
+++ b/contrib/llvm/lib/Linker/LinkItems.cpp
@@ -0,0 +1,241 @@
+//===- lib/Linker/LinkItems.cpp - Link LLVM objects and libraries ---------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains routines to handle linking together LLVM bitcode files,
+// and to handle annoying things like static libraries.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Linker.h"
+#include "llvm/Module.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/system_error.h"
+using namespace llvm;
+
+// LinkItems - This function is the main entry point into linking. It takes a
+// list of LinkItem which indicates the order the files should be linked and
+// how each file should be treated (plain file or with library search). The
+// function only links bitcode and produces a result list of items that are
+// native objects.
+bool
+Linker::LinkInItems(const ItemList& Items, ItemList& NativeItems) {
+ // Clear the NativeItems just in case
+ NativeItems.clear();
+
+ // For each linkage item ...
+ for (ItemList::const_iterator I = Items.begin(), E = Items.end();
+ I != E; ++I) {
+ if (I->second) {
+ // Link in the library suggested.
+ bool is_native = false;
+ if (LinkInLibrary(I->first, is_native))
+ return true;
+ if (is_native)
+ NativeItems.push_back(*I);
+ } else {
+ // Link in the file suggested
+ bool is_native = false;
+ if (LinkInFile(sys::Path(I->first), is_native))
+ return true;
+ if (is_native)
+ NativeItems.push_back(*I);
+ }
+ }
+
+ // At this point we have processed all the link items provided to us. Since
+ // we have an aggregated module at this point, the dependent libraries in
+ // that module should also be aggregated with duplicates eliminated. This is
+ // now the time to process the dependent libraries to resolve any remaining
+ // symbols.
+ bool is_native;
+ for (Module::lib_iterator I = Composite->lib_begin(),
+ E = Composite->lib_end(); I != E; ++I) {
+ if(LinkInLibrary(*I, is_native))
+ return true;
+ if (is_native)
+ NativeItems.push_back(std::make_pair(*I, true));
+ }
+
+ return false;
+}
+
+
+/// LinkInLibrary - links one library into the HeadModule.
+///
+bool Linker::LinkInLibrary(StringRef Lib, bool& is_native) {
+ is_native = false;
+ // Determine where this library lives.
+ sys::Path Pathname = FindLib(Lib);
+ if (Pathname.isEmpty())
+ return error("Cannot find library '" + Lib.str() + "'");
+
+ // If its an archive, try to link it in
+ std::string Magic;
+ Pathname.getMagicNumber(Magic, 64);
+ switch (sys::IdentifyFileType(Magic.c_str(), 64)) {
+ default: llvm_unreachable("Bad file type identification");
+ case sys::Unknown_FileType:
+ return warning("Supposed library '" + Lib.str() + "' isn't a library.");
+
+ case sys::Bitcode_FileType:
+ // LLVM ".so" file.
+ if (LinkInFile(Pathname, is_native))
+ return true;
+ break;
+
+ case sys::Archive_FileType:
+ if (LinkInArchive(Pathname, is_native))
+ return error("Cannot link archive '" + Pathname.str() + "'");
+ break;
+
+ case sys::ELF_Relocatable_FileType:
+ case sys::ELF_SharedObject_FileType:
+ case sys::Mach_O_Object_FileType:
+ case sys::Mach_O_FixedVirtualMemorySharedLib_FileType:
+ case sys::Mach_O_DynamicallyLinkedSharedLib_FileType:
+ case sys::Mach_O_DynamicallyLinkedSharedLibStub_FileType:
+ case sys::COFF_FileType:
+ is_native = true;
+ break;
+ }
+ return false;
+}
+
+/// LinkLibraries - takes the specified library files and links them into the
+/// main bitcode object file.
+///
+/// Inputs:
+/// Libraries - The list of libraries to link into the module.
+///
+/// Return value:
+/// FALSE - No error.
+/// TRUE - Error.
+///
+bool Linker::LinkInLibraries(const std::vector<std::string> &Libraries) {
+
+ // Process the set of libraries we've been provided.
+ bool is_native = false;
+ for (unsigned i = 0; i < Libraries.size(); ++i)
+ if (LinkInLibrary(Libraries[i], is_native))
+ return true;
+
+ // At this point we have processed all the libraries provided to us. Since
+ // we have an aggregated module at this point, the dependent libraries in
+ // that module should also be aggregated with duplicates eliminated. This is
+ // now the time to process the dependent libraries to resolve any remaining
+ // symbols.
+ const Module::LibraryListType& DepLibs = Composite->getLibraries();
+ for (Module::LibraryListType::const_iterator I = DepLibs.begin(),
+ E = DepLibs.end(); I != E; ++I)
+ if (LinkInLibrary(*I, is_native))
+ return true;
+
+ return false;
+}
+
+/// LinkInFile - opens a bitcode file and links in all objects which
+/// provide symbols that are currently undefined.
+///
+/// Inputs:
+/// File - The pathname of the bitcode file.
+///
+/// Outputs:
+/// ErrorMessage - A C++ string detailing what error occurred, if any.
+///
+/// Return Value:
+/// TRUE - An error occurred.
+/// FALSE - No errors.
+///
+bool Linker::LinkInFile(const sys::Path &File, bool &is_native) {
+ is_native = false;
+
+ // Check for a file of name "-", which means "read standard input"
+ if (File.str() == "-") {
+ std::auto_ptr<Module> M;
+ OwningPtr<MemoryBuffer> Buffer;
+ error_code ec;
+ if (!(ec = MemoryBuffer::getSTDIN(Buffer))) {
+ if (!Buffer->getBufferSize()) {
+ Error = "standard input is empty";
+ } else {
+ M.reset(ParseBitcodeFile(Buffer.get(), Context, &Error));
+ if (M.get())
+ if (!LinkInModule(M.get(), &Error))
+ return false;
+ }
+ }
+ return error("Cannot link stdin: " + ec.message());
+ }
+
+ // Determine what variety of file it is.
+ std::string Magic;
+ if (!File.getMagicNumber(Magic, 64))
+ return error("Cannot find linker input '" + File.str() + "'");
+
+ switch (sys::IdentifyFileType(Magic.c_str(), 64)) {
+ default: llvm_unreachable("Bad file type identification");
+ case sys::Unknown_FileType:
+ return warning("Ignoring file '" + File.str() +
+ "' because does not contain bitcode.");
+
+ case sys::Archive_FileType:
+ // A user may specify an ar archive without -l, perhaps because it
+ // is not installed as a library. Detect that and link the archive.
+ if (LinkInArchive(File, is_native))
+ return true;
+ break;
+
+ case sys::Bitcode_FileType: {
+ verbose("Linking bitcode file '" + File.str() + "'");
+ std::auto_ptr<Module> M(LoadObject(File));
+ if (M.get() == 0)
+ return error("Cannot load file '" + File.str() + "': " + Error);
+ if (LinkInModule(M.get(), &Error))
+ return error("Cannot link file '" + File.str() + "': " + Error);
+
+ verbose("Linked in file '" + File.str() + "'");
+ break;
+ }
+
+ case sys::ELF_Relocatable_FileType:
+ case sys::ELF_SharedObject_FileType:
+ case sys::Mach_O_Object_FileType:
+ case sys::Mach_O_FixedVirtualMemorySharedLib_FileType:
+ case sys::Mach_O_DynamicallyLinkedSharedLib_FileType:
+ case sys::Mach_O_DynamicallyLinkedSharedLibStub_FileType:
+ case sys::COFF_FileType:
+ is_native = true;
+ break;
+ }
+ return false;
+}
+
+/// LinkFiles - takes a module and a list of files and links them all together.
+/// It locates the file either in the current directory, as its absolute
+/// or relative pathname, or as a file somewhere in LLVM_LIB_SEARCH_PATH.
+///
+/// Inputs:
+/// Files - A vector of sys::Path indicating the LLVM bitcode filenames
+/// to be linked. The names can refer to a mixture of pure LLVM
+/// bitcode files and archive (ar) formatted files.
+///
+/// Return value:
+/// FALSE - No errors.
+/// TRUE - Some error occurred.
+///
+bool Linker::LinkInFiles(const std::vector<sys::Path> &Files) {
+ bool is_native;
+ for (unsigned i = 0; i < Files.size(); ++i)
+ if (LinkInFile(Files[i], is_native))
+ return true;
+ return false;
+}
diff --git a/contrib/llvm/lib/Linker/LinkModules.cpp b/contrib/llvm/lib/Linker/LinkModules.cpp
new file mode 100644
index 0000000..765fcc8
--- /dev/null
+++ b/contrib/llvm/lib/Linker/LinkModules.cpp
@@ -0,0 +1,1337 @@
+//===- lib/Linker/LinkModules.cpp - Module Linker Implementation ----------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the LLVM module linker.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Linker.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Instructions.h"
+#include "llvm/Module.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/Utils/Cloning.h"
+#include "llvm/Transforms/Utils/ValueMapper.h"
+#include <cctype>
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// TypeMap implementation.
+//===----------------------------------------------------------------------===//
+
+namespace {
+class TypeMapTy : public ValueMapTypeRemapper {
+ /// MappedTypes - This is a mapping from a source type to a destination type
+ /// to use.
+ DenseMap<Type*, Type*> MappedTypes;
+
+ /// SpeculativeTypes - When checking to see if two subgraphs are isomorphic,
+ /// we speculatively add types to MappedTypes, but keep track of them here in
+ /// case we need to roll back.
+ SmallVector<Type*, 16> SpeculativeTypes;
+
+ /// SrcDefinitionsToResolve - This is a list of non-opaque structs in the
+ /// source module that are mapped to an opaque struct in the destination
+ /// module.
+ SmallVector<StructType*, 16> SrcDefinitionsToResolve;
+
+ /// DstResolvedOpaqueTypes - This is the set of opaque types in the
+ /// destination modules who are getting a body from the source module.
+ SmallPtrSet<StructType*, 16> DstResolvedOpaqueTypes;
+
+public:
+ /// addTypeMapping - Indicate that the specified type in the destination
+ /// module is conceptually equivalent to the specified type in the source
+ /// module.
+ void addTypeMapping(Type *DstTy, Type *SrcTy);
+
+ /// linkDefinedTypeBodies - Produce a body for an opaque type in the dest
+ /// module from a type definition in the source module.
+ void linkDefinedTypeBodies();
+
+ /// get - Return the mapped type to use for the specified input type from the
+ /// source module.
+ Type *get(Type *SrcTy);
+
+ FunctionType *get(FunctionType *T) {return cast<FunctionType>(get((Type*)T));}
+
+ /// dump - Dump out the type map for debugging purposes.
+ void dump() const {
+ for (DenseMap<Type*, Type*>::const_iterator
+ I = MappedTypes.begin(), E = MappedTypes.end(); I != E; ++I) {
+ dbgs() << "TypeMap: ";
+ I->first->dump();
+ dbgs() << " => ";
+ I->second->dump();
+ dbgs() << '\n';
+ }
+ }
+
+private:
+ Type *getImpl(Type *T);
+ /// remapType - Implement the ValueMapTypeRemapper interface.
+ Type *remapType(Type *SrcTy) {
+ return get(SrcTy);
+ }
+
+ bool areTypesIsomorphic(Type *DstTy, Type *SrcTy);
+};
+}
+
+void TypeMapTy::addTypeMapping(Type *DstTy, Type *SrcTy) {
+ Type *&Entry = MappedTypes[SrcTy];
+ if (Entry) return;
+
+ if (DstTy == SrcTy) {
+ Entry = DstTy;
+ return;
+ }
+
+ // Check to see if these types are recursively isomorphic and establish a
+ // mapping between them if so.
+ if (!areTypesIsomorphic(DstTy, SrcTy)) {
+ // Oops, they aren't isomorphic. Just discard this request by rolling out
+ // any speculative mappings we've established.
+ for (unsigned i = 0, e = SpeculativeTypes.size(); i != e; ++i)
+ MappedTypes.erase(SpeculativeTypes[i]);
+ }
+ SpeculativeTypes.clear();
+}
+
+/// areTypesIsomorphic - Recursively walk this pair of types, returning true
+/// if they are isomorphic, false if they are not.
+bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) {
+ // Two types with differing kinds are clearly not isomorphic.
+ if (DstTy->getTypeID() != SrcTy->getTypeID()) return false;
+
+ // If we have an entry in the MappedTypes table, then we have our answer.
+ Type *&Entry = MappedTypes[SrcTy];
+ if (Entry)
+ return Entry == DstTy;
+
+ // Two identical types are clearly isomorphic. Remember this
+ // non-speculatively.
+ if (DstTy == SrcTy) {
+ Entry = DstTy;
+ return true;
+ }
+
+ // Okay, we have two types with identical kinds that we haven't seen before.
+
+ // If this is an opaque struct type, special case it.
+ if (StructType *SSTy = dyn_cast<StructType>(SrcTy)) {
+ // Mapping an opaque type to any struct, just keep the dest struct.
+ if (SSTy->isOpaque()) {
+ Entry = DstTy;
+ SpeculativeTypes.push_back(SrcTy);
+ return true;
+ }
+
+ // Mapping a non-opaque source type to an opaque dest. If this is the first
+ // type that we're mapping onto this destination type then we succeed. Keep
+ // the dest, but fill it in later. This doesn't need to be speculative. If
+ // this is the second (different) type that we're trying to map onto the
+ // same opaque type then we fail.
+ if (cast<StructType>(DstTy)->isOpaque()) {
+ // We can only map one source type onto the opaque destination type.
+ if (!DstResolvedOpaqueTypes.insert(cast<StructType>(DstTy)))
+ return false;
+ SrcDefinitionsToResolve.push_back(SSTy);
+ Entry = DstTy;
+ return true;
+ }
+ }
+
+ // If the number of subtypes disagree between the two types, then we fail.
+ if (SrcTy->getNumContainedTypes() != DstTy->getNumContainedTypes())
+ return false;
+
+ // Fail if any of the extra properties (e.g. array size) of the type disagree.
+ if (isa<IntegerType>(DstTy))
+ return false; // bitwidth disagrees.
+ if (PointerType *PT = dyn_cast<PointerType>(DstTy)) {
+ if (PT->getAddressSpace() != cast<PointerType>(SrcTy)->getAddressSpace())
+ return false;
+
+ } else if (FunctionType *FT = dyn_cast<FunctionType>(DstTy)) {
+ if (FT->isVarArg() != cast<FunctionType>(SrcTy)->isVarArg())
+ return false;
+ } else if (StructType *DSTy = dyn_cast<StructType>(DstTy)) {
+ StructType *SSTy = cast<StructType>(SrcTy);
+ if (DSTy->isLiteral() != SSTy->isLiteral() ||
+ DSTy->isPacked() != SSTy->isPacked())
+ return false;
+ } else if (ArrayType *DATy = dyn_cast<ArrayType>(DstTy)) {
+ if (DATy->getNumElements() != cast<ArrayType>(SrcTy)->getNumElements())
+ return false;
+ } else if (VectorType *DVTy = dyn_cast<VectorType>(DstTy)) {
+ if (DVTy->getNumElements() != cast<ArrayType>(SrcTy)->getNumElements())
+ return false;
+ }
+
+ // Otherwise, we speculate that these two types will line up and recursively
+ // check the subelements.
+ Entry = DstTy;
+ SpeculativeTypes.push_back(SrcTy);
+
+ for (unsigned i = 0, e = SrcTy->getNumContainedTypes(); i != e; ++i)
+ if (!areTypesIsomorphic(DstTy->getContainedType(i),
+ SrcTy->getContainedType(i)))
+ return false;
+
+ // If everything seems to have lined up, then everything is great.
+ return true;
+}
+
+/// linkDefinedTypeBodies - Produce a body for an opaque type in the dest
+/// module from a type definition in the source module.
+void TypeMapTy::linkDefinedTypeBodies() {
+ SmallVector<Type*, 16> Elements;
+ SmallString<16> TmpName;
+
+ // Note that processing entries in this loop (calling 'get') can add new
+ // entries to the SrcDefinitionsToResolve vector.
+ while (!SrcDefinitionsToResolve.empty()) {
+ StructType *SrcSTy = SrcDefinitionsToResolve.pop_back_val();
+ StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]);
+
+ // TypeMap is a many-to-one mapping, if there were multiple types that
+ // provide a body for DstSTy then previous iterations of this loop may have
+ // already handled it. Just ignore this case.
+ if (!DstSTy->isOpaque()) continue;
+ assert(!SrcSTy->isOpaque() && "Not resolving a definition?");
+
+ // Map the body of the source type over to a new body for the dest type.
+ Elements.resize(SrcSTy->getNumElements());
+ for (unsigned i = 0, e = Elements.size(); i != e; ++i)
+ Elements[i] = getImpl(SrcSTy->getElementType(i));
+
+ DstSTy->setBody(Elements, SrcSTy->isPacked());
+
+ // If DstSTy has no name or has a longer name than STy, then viciously steal
+ // STy's name.
+ if (!SrcSTy->hasName()) continue;
+ StringRef SrcName = SrcSTy->getName();
+
+ if (!DstSTy->hasName() || DstSTy->getName().size() > SrcName.size()) {
+ TmpName.insert(TmpName.end(), SrcName.begin(), SrcName.end());
+ SrcSTy->setName("");
+ DstSTy->setName(TmpName.str());
+ TmpName.clear();
+ }
+ }
+
+ DstResolvedOpaqueTypes.clear();
+}
+
+/// get - Return the mapped type to use for the specified input type from the
+/// source module.
+Type *TypeMapTy::get(Type *Ty) {
+ Type *Result = getImpl(Ty);
+
+ // If this caused a reference to any struct type, resolve it before returning.
+ if (!SrcDefinitionsToResolve.empty())
+ linkDefinedTypeBodies();
+ return Result;
+}
+
+/// getImpl - This is the recursive version of get().
+Type *TypeMapTy::getImpl(Type *Ty) {
+ // If we already have an entry for this type, return it.
+ Type **Entry = &MappedTypes[Ty];
+ if (*Entry) return *Entry;
+
+ // If this is not a named struct type, then just map all of the elements and
+ // then rebuild the type from inside out.
+ if (!isa<StructType>(Ty) || cast<StructType>(Ty)->isLiteral()) {
+ // If there are no element types to map, then the type is itself. This is
+ // true for the anonymous {} struct, things like 'float', integers, etc.
+ if (Ty->getNumContainedTypes() == 0)
+ return *Entry = Ty;
+
+ // Remap all of the elements, keeping track of whether any of them change.
+ bool AnyChange = false;
+ SmallVector<Type*, 4> ElementTypes;
+ ElementTypes.resize(Ty->getNumContainedTypes());
+ for (unsigned i = 0, e = Ty->getNumContainedTypes(); i != e; ++i) {
+ ElementTypes[i] = getImpl(Ty->getContainedType(i));
+ AnyChange |= ElementTypes[i] != Ty->getContainedType(i);
+ }
+
+ // If we found our type while recursively processing stuff, just use it.
+ Entry = &MappedTypes[Ty];
+ if (*Entry) return *Entry;
+
+ // If all of the element types mapped directly over, then the type is usable
+ // as-is.
+ if (!AnyChange)
+ return *Entry = Ty;
+
+ // Otherwise, rebuild a modified type.
+ switch (Ty->getTypeID()) {
+ default: llvm_unreachable("unknown derived type to remap");
+ case Type::ArrayTyID:
+ return *Entry = ArrayType::get(ElementTypes[0],
+ cast<ArrayType>(Ty)->getNumElements());
+ case Type::VectorTyID:
+ return *Entry = VectorType::get(ElementTypes[0],
+ cast<VectorType>(Ty)->getNumElements());
+ case Type::PointerTyID:
+ return *Entry = PointerType::get(ElementTypes[0],
+ cast<PointerType>(Ty)->getAddressSpace());
+ case Type::FunctionTyID:
+ return *Entry = FunctionType::get(ElementTypes[0],
+ makeArrayRef(ElementTypes).slice(1),
+ cast<FunctionType>(Ty)->isVarArg());
+ case Type::StructTyID:
+ // Note that this is only reached for anonymous structs.
+ return *Entry = StructType::get(Ty->getContext(), ElementTypes,
+ cast<StructType>(Ty)->isPacked());
+ }
+ }
+
+ // Otherwise, this is an unmapped named struct. If the struct can be directly
+ // mapped over, just use it as-is. This happens in a case when the linked-in
+ // module has something like:
+ // %T = type {%T*, i32}
+ // @GV = global %T* null
+ // where T does not exist at all in the destination module.
+ //
+ // The other case we watch for is when the type is not in the destination
+ // module, but that it has to be rebuilt because it refers to something that
+ // is already mapped. For example, if the destination module has:
+ // %A = type { i32 }
+ // and the source module has something like
+ // %A' = type { i32 }
+ // %B = type { %A'* }
+ // @GV = global %B* null
+ // then we want to create a new type: "%B = type { %A*}" and have it take the
+ // pristine "%B" name from the source module.
+ //
+ // To determine which case this is, we have to recursively walk the type graph
+ // speculating that we'll be able to reuse it unmodified. Only if this is
+ // safe would we map the entire thing over. Because this is an optimization,
+ // and is not required for the prettiness of the linked module, we just skip
+ // it and always rebuild a type here.
+ StructType *STy = cast<StructType>(Ty);
+
+ // If the type is opaque, we can just use it directly.
+ if (STy->isOpaque())
+ return *Entry = STy;
+
+ // Otherwise we create a new type and resolve its body later. This will be
+ // resolved by the top level of get().
+ SrcDefinitionsToResolve.push_back(STy);
+ StructType *DTy = StructType::create(STy->getContext());
+ DstResolvedOpaqueTypes.insert(DTy);
+ return *Entry = DTy;
+}
+
+//===----------------------------------------------------------------------===//
+// ModuleLinker implementation.
+//===----------------------------------------------------------------------===//
+
+namespace {
+ /// ModuleLinker - This is an implementation class for the LinkModules
+ /// function, which is the entrypoint for this file.
+ class ModuleLinker {
+ Module *DstM, *SrcM;
+
+ TypeMapTy TypeMap;
+
+ /// ValueMap - Mapping of values from what they used to be in Src, to what
+ /// they are now in DstM. ValueToValueMapTy is a ValueMap, which involves
+ /// some overhead due to the use of Value handles which the Linker doesn't
+ /// actually need, but this allows us to reuse the ValueMapper code.
+ ValueToValueMapTy ValueMap;
+
+ struct AppendingVarInfo {
+ GlobalVariable *NewGV; // New aggregate global in dest module.
+ Constant *DstInit; // Old initializer from dest module.
+ Constant *SrcInit; // Old initializer from src module.
+ };
+
+ std::vector<AppendingVarInfo> AppendingVars;
+
+ unsigned Mode; // Mode to treat source module.
+
+ // Set of items not to link in from source.
+ SmallPtrSet<const Value*, 16> DoNotLinkFromSource;
+
+ // Vector of functions to lazily link in.
+ std::vector<Function*> LazilyLinkFunctions;
+
+ public:
+ std::string ErrorMsg;
+
+ ModuleLinker(Module *dstM, Module *srcM, unsigned mode)
+ : DstM(dstM), SrcM(srcM), Mode(mode) { }
+
+ bool run();
+
+ private:
+ /// emitError - Helper method for setting a message and returning an error
+ /// code.
+ bool emitError(const Twine &Message) {
+ ErrorMsg = Message.str();
+ return true;
+ }
+
+ /// getLinkageResult - This analyzes the two global values and determines
+ /// what the result will look like in the destination module.
+ bool getLinkageResult(GlobalValue *Dest, const GlobalValue *Src,
+ GlobalValue::LinkageTypes &LT,
+ GlobalValue::VisibilityTypes &Vis,
+ bool &LinkFromSrc);
+
+ /// getLinkedToGlobal - Given a global in the source module, return the
+ /// global in the destination module that is being linked to, if any.
+ GlobalValue *getLinkedToGlobal(GlobalValue *SrcGV) {
+ // If the source has no name it can't link. If it has local linkage,
+ // there is no name match-up going on.
+ if (!SrcGV->hasName() || SrcGV->hasLocalLinkage())
+ return 0;
+
+ // Otherwise see if we have a match in the destination module's symtab.
+ GlobalValue *DGV = DstM->getNamedValue(SrcGV->getName());
+ if (DGV == 0) return 0;
+
+ // If we found a global with the same name in the dest module, but it has
+ // internal linkage, we are really not doing any linkage here.
+ if (DGV->hasLocalLinkage())
+ return 0;
+
+ // Otherwise, we do in fact link to the destination global.
+ return DGV;
+ }
+
+ void computeTypeMapping();
+ bool categorizeModuleFlagNodes(const NamedMDNode *ModFlags,
+ DenseMap<MDString*, MDNode*> &ErrorNode,
+ DenseMap<MDString*, MDNode*> &WarningNode,
+ DenseMap<MDString*, MDNode*> &OverrideNode,
+ DenseMap<MDString*,
+ SmallSetVector<MDNode*, 8> > &RequireNodes,
+ SmallSetVector<MDString*, 16> &SeenIDs);
+
+ bool linkAppendingVarProto(GlobalVariable *DstGV, GlobalVariable *SrcGV);
+ bool linkGlobalProto(GlobalVariable *SrcGV);
+ bool linkFunctionProto(Function *SrcF);
+ bool linkAliasProto(GlobalAlias *SrcA);
+ bool linkModuleFlagsMetadata();
+
+ void linkAppendingVarInit(const AppendingVarInfo &AVI);
+ void linkGlobalInits();
+ void linkFunctionBody(Function *Dst, Function *Src);
+ void linkAliasBodies();
+ void linkNamedMDNodes();
+ };
+}
+
+/// forceRenaming - The LLVM SymbolTable class autorenames globals that conflict
+/// in the symbol table. This is good for all clients except for us. Go
+/// through the trouble to force this back.
+static void forceRenaming(GlobalValue *GV, StringRef Name) {
+ // If the global doesn't force its name or if it already has the right name,
+ // there is nothing for us to do.
+ if (GV->hasLocalLinkage() || GV->getName() == Name)
+ return;
+
+ Module *M = GV->getParent();
+
+ // If there is a conflict, rename the conflict.
+ if (GlobalValue *ConflictGV = M->getNamedValue(Name)) {
+ GV->takeName(ConflictGV);
+ ConflictGV->setName(Name); // This will cause ConflictGV to get renamed
+ assert(ConflictGV->getName() != Name && "forceRenaming didn't work");
+ } else {
+ GV->setName(Name); // Force the name back
+ }
+}
+
+/// copyGVAttributes - copy additional attributes (those not needed to construct
+/// a GlobalValue) from the SrcGV to the DestGV.
+static void copyGVAttributes(GlobalValue *DestGV, const GlobalValue *SrcGV) {
+ // Use the maximum alignment, rather than just copying the alignment of SrcGV.
+ unsigned Alignment = std::max(DestGV->getAlignment(), SrcGV->getAlignment());
+ DestGV->copyAttributesFrom(SrcGV);
+ DestGV->setAlignment(Alignment);
+
+ forceRenaming(DestGV, SrcGV->getName());
+}
+
+static bool isLessConstraining(GlobalValue::VisibilityTypes a,
+ GlobalValue::VisibilityTypes b) {
+ if (a == GlobalValue::HiddenVisibility)
+ return false;
+ if (b == GlobalValue::HiddenVisibility)
+ return true;
+ if (a == GlobalValue::ProtectedVisibility)
+ return false;
+ if (b == GlobalValue::ProtectedVisibility)
+ return true;
+ return false;
+}
+
+/// getLinkageResult - This analyzes the two global values and determines what
+/// the result will look like in the destination module. In particular, it
+/// computes the resultant linkage type and visibility, computes whether the
+/// global in the source should be copied over to the destination (replacing
+/// the existing one), and computes whether this linkage is an error or not.
+bool ModuleLinker::getLinkageResult(GlobalValue *Dest, const GlobalValue *Src,
+ GlobalValue::LinkageTypes &LT,
+ GlobalValue::VisibilityTypes &Vis,
+ bool &LinkFromSrc) {
+ assert(Dest && "Must have two globals being queried");
+ assert(!Src->hasLocalLinkage() &&
+ "If Src has internal linkage, Dest shouldn't be set!");
+
+ bool SrcIsDeclaration = Src->isDeclaration() && !Src->isMaterializable();
+ bool DestIsDeclaration = Dest->isDeclaration();
+
+ if (SrcIsDeclaration) {
+ // If Src is external or if both Src & Dest are external.. Just link the
+ // external globals, we aren't adding anything.
+ if (Src->hasDLLImportLinkage()) {
+ // If one of GVs has DLLImport linkage, result should be dllimport'ed.
+ if (DestIsDeclaration) {
+ LinkFromSrc = true;
+ LT = Src->getLinkage();
+ }
+ } else if (Dest->hasExternalWeakLinkage()) {
+ // If the Dest is weak, use the source linkage.
+ LinkFromSrc = true;
+ LT = Src->getLinkage();
+ } else {
+ LinkFromSrc = false;
+ LT = Dest->getLinkage();
+ }
+ } else if (DestIsDeclaration && !Dest->hasDLLImportLinkage()) {
+ // If Dest is external but Src is not:
+ LinkFromSrc = true;
+ LT = Src->getLinkage();
+ } else if (Src->isWeakForLinker()) {
+ // At this point we know that Dest has LinkOnce, External*, Weak, Common,
+ // or DLL* linkage.
+ if (Dest->hasExternalWeakLinkage() ||
+ Dest->hasAvailableExternallyLinkage() ||
+ (Dest->hasLinkOnceLinkage() &&
+ (Src->hasWeakLinkage() || Src->hasCommonLinkage()))) {
+ LinkFromSrc = true;
+ LT = Src->getLinkage();
+ } else {
+ LinkFromSrc = false;
+ LT = Dest->getLinkage();
+ }
+ } else if (Dest->isWeakForLinker()) {
+ // At this point we know that Src has External* or DLL* linkage.
+ if (Src->hasExternalWeakLinkage()) {
+ LinkFromSrc = false;
+ LT = Dest->getLinkage();
+ } else {
+ LinkFromSrc = true;
+ LT = GlobalValue::ExternalLinkage;
+ }
+ } else {
+ assert((Dest->hasExternalLinkage() || Dest->hasDLLImportLinkage() ||
+ Dest->hasDLLExportLinkage() || Dest->hasExternalWeakLinkage()) &&
+ (Src->hasExternalLinkage() || Src->hasDLLImportLinkage() ||
+ Src->hasDLLExportLinkage() || Src->hasExternalWeakLinkage()) &&
+ "Unexpected linkage type!");
+ return emitError("Linking globals named '" + Src->getName() +
+ "': symbol multiply defined!");
+ }
+
+ // Compute the visibility. We follow the rules in the System V Application
+ // Binary Interface.
+ Vis = isLessConstraining(Src->getVisibility(), Dest->getVisibility()) ?
+ Dest->getVisibility() : Src->getVisibility();
+ return false;
+}
+
+/// computeTypeMapping - Loop over all of the linked values to compute type
+/// mappings. For example, if we link "extern Foo *x" and "Foo *x = NULL", then
+/// we have two struct types 'Foo' but one got renamed when the module was
+/// loaded into the same LLVMContext.
+void ModuleLinker::computeTypeMapping() {
+ // Incorporate globals.
+ for (Module::global_iterator I = SrcM->global_begin(),
+ E = SrcM->global_end(); I != E; ++I) {
+ GlobalValue *DGV = getLinkedToGlobal(I);
+ if (DGV == 0) continue;
+
+ if (!DGV->hasAppendingLinkage() || !I->hasAppendingLinkage()) {
+ TypeMap.addTypeMapping(DGV->getType(), I->getType());
+ continue;
+ }
+
+ // Unify the element type of appending arrays.
+ ArrayType *DAT = cast<ArrayType>(DGV->getType()->getElementType());
+ ArrayType *SAT = cast<ArrayType>(I->getType()->getElementType());
+ TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType());
+ }
+
+ // Incorporate functions.
+ for (Module::iterator I = SrcM->begin(), E = SrcM->end(); I != E; ++I) {
+ if (GlobalValue *DGV = getLinkedToGlobal(I))
+ TypeMap.addTypeMapping(DGV->getType(), I->getType());
+ }
+
+ // Incorporate types by name, scanning all the types in the source module.
+ // At this point, the destination module may have a type "%foo = { i32 }" for
+ // example. When the source module got loaded into the same LLVMContext, if
+ // it had the same type, it would have been renamed to "%foo.42 = { i32 }".
+ std::vector<StructType*> SrcStructTypes;
+ SrcM->findUsedStructTypes(SrcStructTypes);
+ SmallPtrSet<StructType*, 32> SrcStructTypesSet(SrcStructTypes.begin(),
+ SrcStructTypes.end());
+
+ std::vector<StructType*> DstStructTypes;
+ DstM->findUsedStructTypes(DstStructTypes);
+ SmallPtrSet<StructType*, 32> DstStructTypesSet(DstStructTypes.begin(),
+ DstStructTypes.end());
+
+ for (unsigned i = 0, e = SrcStructTypes.size(); i != e; ++i) {
+ StructType *ST = SrcStructTypes[i];
+ if (!ST->hasName()) continue;
+
+ // Check to see if there is a dot in the name followed by a digit.
+ size_t DotPos = ST->getName().rfind('.');
+ if (DotPos == 0 || DotPos == StringRef::npos ||
+ ST->getName().back() == '.' || !isdigit(ST->getName()[DotPos+1]))
+ continue;
+
+ // Check to see if the destination module has a struct with the prefix name.
+ if (StructType *DST = DstM->getTypeByName(ST->getName().substr(0, DotPos)))
+ // Don't use it if this actually came from the source module. They're in
+ // the same LLVMContext after all. Also don't use it unless the type is
+ // actually used in the destination module. This can happen in situations
+ // like this:
+ //
+ // Module A Module B
+ // -------- --------
+ // %Z = type { %A } %B = type { %C.1 }
+ // %A = type { %B.1, [7 x i8] } %C.1 = type { i8* }
+ // %B.1 = type { %C } %A.2 = type { %B.3, [5 x i8] }
+ // %C = type { i8* } %B.3 = type { %C.1 }
+ //
+ // When we link Module B with Module A, the '%B' in Module B is
+ // used. However, that would then use '%C.1'. But when we process '%C.1',
+ // we prefer to take the '%C' version. So we are then left with both
+ // '%C.1' and '%C' being used for the same types. This leads to some
+ // variables using one type and some using the other.
+ if (!SrcStructTypesSet.count(DST) && DstStructTypesSet.count(DST))
+ TypeMap.addTypeMapping(DST, ST);
+ }
+
+ // Don't bother incorporating aliases, they aren't generally typed well.
+
+ // Now that we have discovered all of the type equivalences, get a body for
+ // any 'opaque' types in the dest module that are now resolved.
+ TypeMap.linkDefinedTypeBodies();
+}
+
+/// linkAppendingVarProto - If there were any appending global variables, link
+/// them together now. Return true on error.
+bool ModuleLinker::linkAppendingVarProto(GlobalVariable *DstGV,
+ GlobalVariable *SrcGV) {
+
+ if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage())
+ return emitError("Linking globals named '" + SrcGV->getName() +
+ "': can only link appending global with another appending global!");
+
+ ArrayType *DstTy = cast<ArrayType>(DstGV->getType()->getElementType());
+ ArrayType *SrcTy =
+ cast<ArrayType>(TypeMap.get(SrcGV->getType()->getElementType()));
+ Type *EltTy = DstTy->getElementType();
+
+ // Check to see that they two arrays agree on type.
+ if (EltTy != SrcTy->getElementType())
+ return emitError("Appending variables with different element types!");
+ if (DstGV->isConstant() != SrcGV->isConstant())
+ return emitError("Appending variables linked with different const'ness!");
+
+ if (DstGV->getAlignment() != SrcGV->getAlignment())
+ return emitError(
+ "Appending variables with different alignment need to be linked!");
+
+ if (DstGV->getVisibility() != SrcGV->getVisibility())
+ return emitError(
+ "Appending variables with different visibility need to be linked!");
+
+ if (DstGV->getSection() != SrcGV->getSection())
+ return emitError(
+ "Appending variables with different section name need to be linked!");
+
+ uint64_t NewSize = DstTy->getNumElements() + SrcTy->getNumElements();
+ ArrayType *NewType = ArrayType::get(EltTy, NewSize);
+
+ // Create the new global variable.
+ GlobalVariable *NG =
+ new GlobalVariable(*DstGV->getParent(), NewType, SrcGV->isConstant(),
+ DstGV->getLinkage(), /*init*/0, /*name*/"", DstGV,
+ DstGV->isThreadLocal(),
+ DstGV->getType()->getAddressSpace());
+
+ // Propagate alignment, visibility and section info.
+ copyGVAttributes(NG, DstGV);
+
+ AppendingVarInfo AVI;
+ AVI.NewGV = NG;
+ AVI.DstInit = DstGV->getInitializer();
+ AVI.SrcInit = SrcGV->getInitializer();
+ AppendingVars.push_back(AVI);
+
+ // Replace any uses of the two global variables with uses of the new
+ // global.
+ ValueMap[SrcGV] = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
+
+ DstGV->replaceAllUsesWith(ConstantExpr::getBitCast(NG, DstGV->getType()));
+ DstGV->eraseFromParent();
+
+ // Track the source variable so we don't try to link it.
+ DoNotLinkFromSource.insert(SrcGV);
+
+ return false;
+}
+
+/// linkGlobalProto - Loop through the global variables in the src module and
+/// merge them into the dest module.
+bool ModuleLinker::linkGlobalProto(GlobalVariable *SGV) {
+ GlobalValue *DGV = getLinkedToGlobal(SGV);
+ llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility;
+
+ if (DGV) {
+ // Concatenation of appending linkage variables is magic and handled later.
+ if (DGV->hasAppendingLinkage() || SGV->hasAppendingLinkage())
+ return linkAppendingVarProto(cast<GlobalVariable>(DGV), SGV);
+
+ // Determine whether linkage of these two globals follows the source
+ // module's definition or the destination module's definition.
+ GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage;
+ GlobalValue::VisibilityTypes NV;
+ bool LinkFromSrc = false;
+ if (getLinkageResult(DGV, SGV, NewLinkage, NV, LinkFromSrc))
+ return true;
+ NewVisibility = NV;
+
+ // If we're not linking from the source, then keep the definition that we
+ // have.
+ if (!LinkFromSrc) {
+ // Special case for const propagation.
+ if (GlobalVariable *DGVar = dyn_cast<GlobalVariable>(DGV))
+ if (DGVar->isDeclaration() && SGV->isConstant() && !DGVar->isConstant())
+ DGVar->setConstant(true);
+
+ // Set calculated linkage and visibility.
+ DGV->setLinkage(NewLinkage);
+ DGV->setVisibility(*NewVisibility);
+
+ // Make sure to remember this mapping.
+ ValueMap[SGV] = ConstantExpr::getBitCast(DGV,TypeMap.get(SGV->getType()));
+
+ // Track the source global so that we don't attempt to copy it over when
+ // processing global initializers.
+ DoNotLinkFromSource.insert(SGV);
+
+ return false;
+ }
+ }
+
+ // No linking to be performed or linking from the source: simply create an
+ // identical version of the symbol over in the dest module... the
+ // initializer will be filled in later by LinkGlobalInits.
+ GlobalVariable *NewDGV =
+ new GlobalVariable(*DstM, TypeMap.get(SGV->getType()->getElementType()),
+ SGV->isConstant(), SGV->getLinkage(), /*init*/0,
+ SGV->getName(), /*insertbefore*/0,
+ SGV->isThreadLocal(),
+ SGV->getType()->getAddressSpace());
+ // Propagate alignment, visibility and section info.
+ copyGVAttributes(NewDGV, SGV);
+ if (NewVisibility)
+ NewDGV->setVisibility(*NewVisibility);
+
+ if (DGV) {
+ DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDGV, DGV->getType()));
+ DGV->eraseFromParent();
+ }
+
+ // Make sure to remember this mapping.
+ ValueMap[SGV] = NewDGV;
+ return false;
+}
+
+/// linkFunctionProto - Link the function in the source module into the
+/// destination module if needed, setting up mapping information.
+bool ModuleLinker::linkFunctionProto(Function *SF) {
+ GlobalValue *DGV = getLinkedToGlobal(SF);
+ llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility;
+
+ if (DGV) {
+ GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage;
+ bool LinkFromSrc = false;
+ GlobalValue::VisibilityTypes NV;
+ if (getLinkageResult(DGV, SF, NewLinkage, NV, LinkFromSrc))
+ return true;
+ NewVisibility = NV;
+
+ if (!LinkFromSrc) {
+ // Set calculated linkage
+ DGV->setLinkage(NewLinkage);
+ DGV->setVisibility(*NewVisibility);
+
+ // Make sure to remember this mapping.
+ ValueMap[SF] = ConstantExpr::getBitCast(DGV, TypeMap.get(SF->getType()));
+
+ // Track the function from the source module so we don't attempt to remap
+ // it.
+ DoNotLinkFromSource.insert(SF);
+
+ return false;
+ }
+ }
+
+ // If there is no linkage to be performed or we are linking from the source,
+ // bring SF over.
+ Function *NewDF = Function::Create(TypeMap.get(SF->getFunctionType()),
+ SF->getLinkage(), SF->getName(), DstM);
+ copyGVAttributes(NewDF, SF);
+ if (NewVisibility)
+ NewDF->setVisibility(*NewVisibility);
+
+ if (DGV) {
+ // Any uses of DF need to change to NewDF, with cast.
+ DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDF, DGV->getType()));
+ DGV->eraseFromParent();
+ } else {
+ // Internal, LO_ODR, or LO linkage - stick in set to ignore and lazily link.
+ if (SF->hasLocalLinkage() || SF->hasLinkOnceLinkage() ||
+ SF->hasAvailableExternallyLinkage()) {
+ DoNotLinkFromSource.insert(SF);
+ LazilyLinkFunctions.push_back(SF);
+ }
+ }
+
+ ValueMap[SF] = NewDF;
+ return false;
+}
+
+/// LinkAliasProto - Set up prototypes for any aliases that come over from the
+/// source module.
+bool ModuleLinker::linkAliasProto(GlobalAlias *SGA) {
+ GlobalValue *DGV = getLinkedToGlobal(SGA);
+ llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility;
+
+ if (DGV) {
+ GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage;
+ GlobalValue::VisibilityTypes NV;
+ bool LinkFromSrc = false;
+ if (getLinkageResult(DGV, SGA, NewLinkage, NV, LinkFromSrc))
+ return true;
+ NewVisibility = NV;
+
+ if (!LinkFromSrc) {
+ // Set calculated linkage.
+ DGV->setLinkage(NewLinkage);
+ DGV->setVisibility(*NewVisibility);
+
+ // Make sure to remember this mapping.
+ ValueMap[SGA] = ConstantExpr::getBitCast(DGV,TypeMap.get(SGA->getType()));
+
+ // Track the alias from the source module so we don't attempt to remap it.
+ DoNotLinkFromSource.insert(SGA);
+
+ return false;
+ }
+ }
+
+ // If there is no linkage to be performed or we're linking from the source,
+ // bring over SGA.
+ GlobalAlias *NewDA = new GlobalAlias(TypeMap.get(SGA->getType()),
+ SGA->getLinkage(), SGA->getName(),
+ /*aliasee*/0, DstM);
+ copyGVAttributes(NewDA, SGA);
+ if (NewVisibility)
+ NewDA->setVisibility(*NewVisibility);
+
+ if (DGV) {
+ // Any uses of DGV need to change to NewDA, with cast.
+ DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDA, DGV->getType()));
+ DGV->eraseFromParent();
+ }
+
+ ValueMap[SGA] = NewDA;
+ return false;
+}
+
+static void getArrayElements(Constant *C, SmallVectorImpl<Constant*> &Dest) {
+ unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements();
+
+ for (unsigned i = 0; i != NumElements; ++i)
+ Dest.push_back(C->getAggregateElement(i));
+}
+
+void ModuleLinker::linkAppendingVarInit(const AppendingVarInfo &AVI) {
+ // Merge the initializer.
+ SmallVector<Constant*, 16> Elements;
+ getArrayElements(AVI.DstInit, Elements);
+
+ Constant *SrcInit = MapValue(AVI.SrcInit, ValueMap, RF_None, &TypeMap);
+ getArrayElements(SrcInit, Elements);
+
+ ArrayType *NewType = cast<ArrayType>(AVI.NewGV->getType()->getElementType());
+ AVI.NewGV->setInitializer(ConstantArray::get(NewType, Elements));
+}
+
+/// linkGlobalInits - Update the initializers in the Dest module now that all
+/// globals that may be referenced are in Dest.
+void ModuleLinker::linkGlobalInits() {
+ // Loop over all of the globals in the src module, mapping them over as we go
+ for (Module::const_global_iterator I = SrcM->global_begin(),
+ E = SrcM->global_end(); I != E; ++I) {
+
+ // Only process initialized GV's or ones not already in dest.
+ if (!I->hasInitializer() || DoNotLinkFromSource.count(I)) continue;
+
+ // Grab destination global variable.
+ GlobalVariable *DGV = cast<GlobalVariable>(ValueMap[I]);
+ // Figure out what the initializer looks like in the dest module.
+ DGV->setInitializer(MapValue(I->getInitializer(), ValueMap,
+ RF_None, &TypeMap));
+ }
+}
+
+/// linkFunctionBody - Copy the source function over into the dest function and
+/// fix up references to values. At this point we know that Dest is an external
+/// function, and that Src is not.
+void ModuleLinker::linkFunctionBody(Function *Dst, Function *Src) {
+ assert(Src && Dst && Dst->isDeclaration() && !Src->isDeclaration());
+
+ // Go through and convert function arguments over, remembering the mapping.
+ Function::arg_iterator DI = Dst->arg_begin();
+ for (Function::arg_iterator I = Src->arg_begin(), E = Src->arg_end();
+ I != E; ++I, ++DI) {
+ DI->setName(I->getName()); // Copy the name over.
+
+ // Add a mapping to our mapping.
+ ValueMap[I] = DI;
+ }
+
+ if (Mode == Linker::DestroySource) {
+ // Splice the body of the source function into the dest function.
+ Dst->getBasicBlockList().splice(Dst->end(), Src->getBasicBlockList());
+
+ // At this point, all of the instructions and values of the function are now
+ // copied over. The only problem is that they are still referencing values in
+ // the Source function as operands. Loop through all of the operands of the
+ // functions and patch them up to point to the local versions.
+ for (Function::iterator BB = Dst->begin(), BE = Dst->end(); BB != BE; ++BB)
+ for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
+ RemapInstruction(I, ValueMap, RF_IgnoreMissingEntries, &TypeMap);
+
+ } else {
+ // Clone the body of the function into the dest function.
+ SmallVector<ReturnInst*, 8> Returns; // Ignore returns.
+ CloneFunctionInto(Dst, Src, ValueMap, false, Returns, "", NULL, &TypeMap);
+ }
+
+ // There is no need to map the arguments anymore.
+ for (Function::arg_iterator I = Src->arg_begin(), E = Src->arg_end();
+ I != E; ++I)
+ ValueMap.erase(I);
+
+}
+
+/// linkAliasBodies - Insert all of the aliases in Src into the Dest module.
+void ModuleLinker::linkAliasBodies() {
+ for (Module::alias_iterator I = SrcM->alias_begin(), E = SrcM->alias_end();
+ I != E; ++I) {
+ if (DoNotLinkFromSource.count(I))
+ continue;
+ if (Constant *Aliasee = I->getAliasee()) {
+ GlobalAlias *DA = cast<GlobalAlias>(ValueMap[I]);
+ DA->setAliasee(MapValue(Aliasee, ValueMap, RF_None, &TypeMap));
+ }
+ }
+}
+
+/// linkNamedMDNodes - Insert all of the named MDNodes in Src into the Dest
+/// module.
+void ModuleLinker::linkNamedMDNodes() {
+ const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
+ for (Module::const_named_metadata_iterator I = SrcM->named_metadata_begin(),
+ E = SrcM->named_metadata_end(); I != E; ++I) {
+ // Don't link module flags here. Do them separately.
+ if (&*I == SrcModFlags) continue;
+ NamedMDNode *DestNMD = DstM->getOrInsertNamedMetadata(I->getName());
+ // Add Src elements into Dest node.
+ for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
+ DestNMD->addOperand(MapValue(I->getOperand(i), ValueMap,
+ RF_None, &TypeMap));
+ }
+}
+
+/// categorizeModuleFlagNodes - Categorize the module flags according to their
+/// type: Error, Warning, Override, and Require.
+bool ModuleLinker::
+categorizeModuleFlagNodes(const NamedMDNode *ModFlags,
+ DenseMap<MDString*, MDNode*> &ErrorNode,
+ DenseMap<MDString*, MDNode*> &WarningNode,
+ DenseMap<MDString*, MDNode*> &OverrideNode,
+ DenseMap<MDString*,
+ SmallSetVector<MDNode*, 8> > &RequireNodes,
+ SmallSetVector<MDString*, 16> &SeenIDs) {
+ bool HasErr = false;
+
+ for (unsigned I = 0, E = ModFlags->getNumOperands(); I != E; ++I) {
+ MDNode *Op = ModFlags->getOperand(I);
+ assert(Op->getNumOperands() == 3 && "Invalid module flag metadata!");
+ assert(isa<ConstantInt>(Op->getOperand(0)) &&
+ "Module flag's first operand must be an integer!");
+ assert(isa<MDString>(Op->getOperand(1)) &&
+ "Module flag's second operand must be an MDString!");
+
+ ConstantInt *Behavior = cast<ConstantInt>(Op->getOperand(0));
+ MDString *ID = cast<MDString>(Op->getOperand(1));
+ Value *Val = Op->getOperand(2);
+ switch (Behavior->getZExtValue()) {
+ default:
+ assert(false && "Invalid behavior in module flag metadata!");
+ break;
+ case Module::Error: {
+ MDNode *&ErrNode = ErrorNode[ID];
+ if (!ErrNode) ErrNode = Op;
+ if (ErrNode->getOperand(2) != Val)
+ HasErr = emitError("linking module flags '" + ID->getString() +
+ "': IDs have conflicting values");
+ break;
+ }
+ case Module::Warning: {
+ MDNode *&WarnNode = WarningNode[ID];
+ if (!WarnNode) WarnNode = Op;
+ if (WarnNode->getOperand(2) != Val)
+ errs() << "WARNING: linking module flags '" << ID->getString()
+ << "': IDs have conflicting values";
+ break;
+ }
+ case Module::Require: RequireNodes[ID].insert(Op); break;
+ case Module::Override: {
+ MDNode *&OvrNode = OverrideNode[ID];
+ if (!OvrNode) OvrNode = Op;
+ if (OvrNode->getOperand(2) != Val)
+ HasErr = emitError("linking module flags '" + ID->getString() +
+ "': IDs have conflicting override values");
+ break;
+ }
+ }
+
+ SeenIDs.insert(ID);
+ }
+
+ return HasErr;
+}
+
+/// linkModuleFlagsMetadata - Merge the linker flags in Src into the Dest
+/// module.
+bool ModuleLinker::linkModuleFlagsMetadata() {
+ const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
+ if (!SrcModFlags) return false;
+
+ NamedMDNode *DstModFlags = DstM->getOrInsertModuleFlagsMetadata();
+
+ // If the destination module doesn't have module flags yet, then just copy
+ // over the source module's flags.
+ if (DstModFlags->getNumOperands() == 0) {
+ for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
+ DstModFlags->addOperand(SrcModFlags->getOperand(I));
+
+ return false;
+ }
+
+ bool HasErr = false;
+
+ // Otherwise, we have to merge them based on their behaviors. First,
+ // categorize all of the nodes in the modules' module flags. If an error or
+ // warning occurs, then emit the appropriate message(s).
+ DenseMap<MDString*, MDNode*> ErrorNode;
+ DenseMap<MDString*, MDNode*> WarningNode;
+ DenseMap<MDString*, MDNode*> OverrideNode;
+ DenseMap<MDString*, SmallSetVector<MDNode*, 8> > RequireNodes;
+ SmallSetVector<MDString*, 16> SeenIDs;
+
+ HasErr |= categorizeModuleFlagNodes(SrcModFlags, ErrorNode, WarningNode,
+ OverrideNode, RequireNodes, SeenIDs);
+ HasErr |= categorizeModuleFlagNodes(DstModFlags, ErrorNode, WarningNode,
+ OverrideNode, RequireNodes, SeenIDs);
+
+ // Check that there isn't both an error and warning node for a flag.
+ for (SmallSetVector<MDString*, 16>::iterator
+ I = SeenIDs.begin(), E = SeenIDs.end(); I != E; ++I) {
+ MDString *ID = *I;
+ if (ErrorNode[ID] && WarningNode[ID])
+ HasErr = emitError("linking module flags '" + ID->getString() +
+ "': IDs have conflicting behaviors");
+ }
+
+ // Early exit if we had an error.
+ if (HasErr) return true;
+
+ // Get the destination's module flags ready for new operands.
+ DstModFlags->dropAllReferences();
+
+ // Add all of the module flags to the destination module.
+ DenseMap<MDString*, SmallVector<MDNode*, 4> > AddedNodes;
+ for (SmallSetVector<MDString*, 16>::iterator
+ I = SeenIDs.begin(), E = SeenIDs.end(); I != E; ++I) {
+ MDString *ID = *I;
+ if (OverrideNode[ID]) {
+ DstModFlags->addOperand(OverrideNode[ID]);
+ AddedNodes[ID].push_back(OverrideNode[ID]);
+ } else if (ErrorNode[ID]) {
+ DstModFlags->addOperand(ErrorNode[ID]);
+ AddedNodes[ID].push_back(ErrorNode[ID]);
+ } else if (WarningNode[ID]) {
+ DstModFlags->addOperand(WarningNode[ID]);
+ AddedNodes[ID].push_back(WarningNode[ID]);
+ }
+
+ for (SmallSetVector<MDNode*, 8>::iterator
+ II = RequireNodes[ID].begin(), IE = RequireNodes[ID].end();
+ II != IE; ++II)
+ DstModFlags->addOperand(*II);
+ }
+
+ // Now check that all of the requirements have been satisfied.
+ for (SmallSetVector<MDString*, 16>::iterator
+ I = SeenIDs.begin(), E = SeenIDs.end(); I != E; ++I) {
+ MDString *ID = *I;
+ SmallSetVector<MDNode*, 8> &Set = RequireNodes[ID];
+
+ for (SmallSetVector<MDNode*, 8>::iterator
+ II = Set.begin(), IE = Set.end(); II != IE; ++II) {
+ MDNode *Node = *II;
+ assert(isa<MDNode>(Node->getOperand(2)) &&
+ "Module flag's third operand must be an MDNode!");
+ MDNode *Val = cast<MDNode>(Node->getOperand(2));
+
+ MDString *ReqID = cast<MDString>(Val->getOperand(0));
+ Value *ReqVal = Val->getOperand(1);
+
+ bool HasValue = false;
+ for (SmallVectorImpl<MDNode*>::iterator
+ RI = AddedNodes[ReqID].begin(), RE = AddedNodes[ReqID].end();
+ RI != RE; ++RI) {
+ MDNode *ReqNode = *RI;
+ if (ReqNode->getOperand(2) == ReqVal) {
+ HasValue = true;
+ break;
+ }
+ }
+
+ if (!HasValue)
+ HasErr = emitError("linking module flags '" + ReqID->getString() +
+ "': does not have the required value");
+ }
+ }
+
+ return HasErr;
+}
+
+bool ModuleLinker::run() {
+ assert(DstM && "Null destination module");
+ assert(SrcM && "Null source module");
+
+ // Inherit the target data from the source module if the destination module
+ // doesn't have one already.
+ if (DstM->getDataLayout().empty() && !SrcM->getDataLayout().empty())
+ DstM->setDataLayout(SrcM->getDataLayout());
+
+ // Copy the target triple from the source to dest if the dest's is empty.
+ if (DstM->getTargetTriple().empty() && !SrcM->getTargetTriple().empty())
+ DstM->setTargetTriple(SrcM->getTargetTriple());
+
+ if (!SrcM->getDataLayout().empty() && !DstM->getDataLayout().empty() &&
+ SrcM->getDataLayout() != DstM->getDataLayout())
+ errs() << "WARNING: Linking two modules of different data layouts!\n";
+ if (!SrcM->getTargetTriple().empty() &&
+ DstM->getTargetTriple() != SrcM->getTargetTriple()) {
+ errs() << "WARNING: Linking two modules of different target triples: ";
+ if (!SrcM->getModuleIdentifier().empty())
+ errs() << SrcM->getModuleIdentifier() << ": ";
+ errs() << "'" << SrcM->getTargetTriple() << "' and '"
+ << DstM->getTargetTriple() << "'\n";
+ }
+
+ // Append the module inline asm string.
+ if (!SrcM->getModuleInlineAsm().empty()) {
+ if (DstM->getModuleInlineAsm().empty())
+ DstM->setModuleInlineAsm(SrcM->getModuleInlineAsm());
+ else
+ DstM->setModuleInlineAsm(DstM->getModuleInlineAsm()+"\n"+
+ SrcM->getModuleInlineAsm());
+ }
+
+ // Update the destination module's dependent libraries list with the libraries
+ // from the source module. There's no opportunity for duplicates here as the
+ // Module ensures that duplicate insertions are discarded.
+ for (Module::lib_iterator SI = SrcM->lib_begin(), SE = SrcM->lib_end();
+ SI != SE; ++SI)
+ DstM->addLibrary(*SI);
+
+ // If the source library's module id is in the dependent library list of the
+ // destination library, remove it since that module is now linked in.
+ StringRef ModuleId = SrcM->getModuleIdentifier();
+ if (!ModuleId.empty())
+ DstM->removeLibrary(sys::path::stem(ModuleId));
+
+ // Loop over all of the linked values to compute type mappings.
+ computeTypeMapping();
+
+ // Insert all of the globals in src into the DstM module... without linking
+ // initializers (which could refer to functions not yet mapped over).
+ for (Module::global_iterator I = SrcM->global_begin(),
+ E = SrcM->global_end(); I != E; ++I)
+ if (linkGlobalProto(I))
+ return true;
+
+ // Link the functions together between the two modules, without doing function
+ // bodies... this just adds external function prototypes to the DstM
+ // function... We do this so that when we begin processing function bodies,
+ // all of the global values that may be referenced are available in our
+ // ValueMap.
+ for (Module::iterator I = SrcM->begin(), E = SrcM->end(); I != E; ++I)
+ if (linkFunctionProto(I))
+ return true;
+
+ // If there were any aliases, link them now.
+ for (Module::alias_iterator I = SrcM->alias_begin(),
+ E = SrcM->alias_end(); I != E; ++I)
+ if (linkAliasProto(I))
+ return true;
+
+ for (unsigned i = 0, e = AppendingVars.size(); i != e; ++i)
+ linkAppendingVarInit(AppendingVars[i]);
+
+ // Update the initializers in the DstM module now that all globals that may
+ // be referenced are in DstM.
+ linkGlobalInits();
+
+ // Link in the function bodies that are defined in the source module into
+ // DstM.
+ for (Module::iterator SF = SrcM->begin(), E = SrcM->end(); SF != E; ++SF) {
+ // Skip if not linking from source.
+ if (DoNotLinkFromSource.count(SF)) continue;
+
+ // Skip if no body (function is external) or materialize.
+ if (SF->isDeclaration()) {
+ if (!SF->isMaterializable())
+ continue;
+ if (SF->Materialize(&ErrorMsg))
+ return true;
+ }
+
+ linkFunctionBody(cast<Function>(ValueMap[SF]), SF);
+ SF->Dematerialize();
+ }
+
+ // Resolve all uses of aliases with aliasees.
+ linkAliasBodies();
+
+ // Remap all of the named MDNodes in Src into the DstM module. We do this
+ // after linking GlobalValues so that MDNodes that reference GlobalValues
+ // are properly remapped.
+ linkNamedMDNodes();
+
+ // Merge the module flags into the DstM module.
+ if (linkModuleFlagsMetadata())
+ return true;
+
+ // Process vector of lazily linked in functions.
+ bool LinkedInAnyFunctions;
+ do {
+ LinkedInAnyFunctions = false;
+
+ for(std::vector<Function*>::iterator I = LazilyLinkFunctions.begin(),
+ E = LazilyLinkFunctions.end(); I != E; ++I) {
+ if (!*I)
+ continue;
+
+ Function *SF = *I;
+ Function *DF = cast<Function>(ValueMap[SF]);
+
+ if (!DF->use_empty()) {
+
+ // Materialize if necessary.
+ if (SF->isDeclaration()) {
+ if (!SF->isMaterializable())
+ continue;
+ if (SF->Materialize(&ErrorMsg))
+ return true;
+ }
+
+ // Link in function body.
+ linkFunctionBody(DF, SF);
+ SF->Dematerialize();
+
+ // "Remove" from vector by setting the element to 0.
+ *I = 0;
+
+ // Set flag to indicate we may have more functions to lazily link in
+ // since we linked in a function.
+ LinkedInAnyFunctions = true;
+ }
+ }
+ } while (LinkedInAnyFunctions);
+
+ // Remove any prototypes of functions that were not actually linked in.
+ for(std::vector<Function*>::iterator I = LazilyLinkFunctions.begin(),
+ E = LazilyLinkFunctions.end(); I != E; ++I) {
+ if (!*I)
+ continue;
+
+ Function *SF = *I;
+ Function *DF = cast<Function>(ValueMap[SF]);
+ if (DF->use_empty())
+ DF->eraseFromParent();
+ }
+
+ // Now that all of the types from the source are used, resolve any structs
+ // copied over to the dest that didn't exist there.
+ TypeMap.linkDefinedTypeBodies();
+
+ return false;
+}
+
+//===----------------------------------------------------------------------===//
+// LinkModules entrypoint.
+//===----------------------------------------------------------------------===//
+
+/// LinkModules - This function links two modules together, with the resulting
+/// left 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, Module *Src, unsigned Mode,
+ std::string *ErrorMsg) {
+ ModuleLinker TheLinker(Dest, Src, Mode);
+ if (TheLinker.run()) {
+ if (ErrorMsg) *ErrorMsg = TheLinker.ErrorMsg;
+ return true;
+ }
+
+ return false;
+}
diff --git a/contrib/llvm/lib/Linker/Linker.cpp b/contrib/llvm/lib/Linker/Linker.cpp
new file mode 100644
index 0000000..7c6cf4f
--- /dev/null
+++ b/contrib/llvm/lib/Linker/Linker.cpp
@@ -0,0 +1,181 @@
+//===- lib/Linker/Linker.cpp - Basic Linker functionality ----------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains basic Linker functionality that all usages will need.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Linker.h"
+#include "llvm/Module.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/system_error.h"
+using namespace llvm;
+
+Linker::Linker(StringRef progname, StringRef modname,
+ LLVMContext& C, unsigned flags):
+ Context(C),
+ Composite(new Module(modname, C)),
+ LibPaths(),
+ Flags(flags),
+ Error(),
+ ProgramName(progname) { }
+
+Linker::Linker(StringRef progname, Module* aModule, unsigned flags) :
+ Context(aModule->getContext()),
+ Composite(aModule),
+ LibPaths(),
+ Flags(flags),
+ Error(),
+ ProgramName(progname) { }
+
+Linker::~Linker() {
+ delete Composite;
+}
+
+bool
+Linker::error(StringRef message) {
+ Error = message;
+ if (!(Flags&QuietErrors))
+ errs() << ProgramName << ": error: " << message << "\n";
+ return true;
+}
+
+bool
+Linker::warning(StringRef message) {
+ Error = message;
+ if (!(Flags&QuietWarnings))
+ errs() << ProgramName << ": warning: " << message << "\n";
+ return false;
+}
+
+void
+Linker::verbose(StringRef message) {
+ if (Flags&Verbose)
+ errs() << " " << message << "\n";
+}
+
+void
+Linker::addPath(const sys::Path& path) {
+ LibPaths.push_back(path);
+}
+
+void
+Linker::addPaths(const std::vector<std::string>& paths) {
+ for (unsigned i = 0, e = paths.size(); i != e; ++i)
+ LibPaths.push_back(sys::Path(paths[i]));
+}
+
+void
+Linker::addSystemPaths() {
+ sys::Path::GetBitcodeLibraryPaths(LibPaths);
+ LibPaths.insert(LibPaths.begin(),sys::Path("./"));
+}
+
+Module*
+Linker::releaseModule() {
+ Module* result = Composite;
+ LibPaths.clear();
+ Error.clear();
+ Composite = 0;
+ Flags = 0;
+ return result;
+}
+
+// LoadObject - Read in and parse the bitcode file named by FN and return the
+// module it contains (wrapped in an auto_ptr), or auto_ptr<Module>() and set
+// Error if an error occurs.
+std::auto_ptr<Module>
+Linker::LoadObject(const sys::Path &FN) {
+ std::string ParseErrorMessage;
+ Module *Result = 0;
+
+ OwningPtr<MemoryBuffer> Buffer;
+ if (error_code ec = MemoryBuffer::getFileOrSTDIN(FN.c_str(), Buffer))
+ ParseErrorMessage = "Error reading file '" + FN.str() + "'" + ": "
+ + ec.message();
+ else
+ Result = ParseBitcodeFile(Buffer.get(), Context, &ParseErrorMessage);
+
+ if (Result)
+ return std::auto_ptr<Module>(Result);
+ Error = "Bitcode file '" + FN.str() + "' could not be loaded";
+ if (ParseErrorMessage.size())
+ Error += ": " + ParseErrorMessage;
+ return std::auto_ptr<Module>();
+}
+
+// IsLibrary - Determine if "Name" is a library in "Directory". Return
+// a non-empty sys::Path if its found, an empty one otherwise.
+static inline sys::Path IsLibrary(StringRef Name,
+ const sys::Path &Directory) {
+
+ sys::Path FullPath(Directory);
+
+ // Try the libX.a form
+ FullPath.appendComponent(("lib" + Name).str());
+ FullPath.appendSuffix("a");
+ if (FullPath.isArchive())
+ return FullPath;
+
+ // Try the libX.bca form
+ FullPath.eraseSuffix();
+ FullPath.appendSuffix("bca");
+ if (FullPath.isArchive())
+ return FullPath;
+
+ // Try the libX.so (or .dylib) form
+ FullPath.eraseSuffix();
+ FullPath.appendSuffix(sys::Path::GetDLLSuffix());
+ if (FullPath.isDynamicLibrary()) // Native shared library?
+ return FullPath;
+ if (FullPath.isBitcodeFile()) // .so file containing bitcode?
+ return FullPath;
+
+ // Try libX form, to make it possible to add dependency on the
+ // specific version of .so, like liblzma.so.1.0.0
+ FullPath.eraseSuffix();
+ if (FullPath.isDynamicLibrary()) // Native shared library?
+ return FullPath;
+ if (FullPath.isBitcodeFile()) // .so file containing bitcode?
+ return FullPath;
+
+ // Not found .. fall through
+
+ // Indicate that the library was not found in the directory.
+ FullPath.clear();
+ return FullPath;
+}
+
+/// FindLib - Try to convert Filename into the name of a file that we can open,
+/// if it does not already name a file we can open, by first trying to open
+/// Filename, then libFilename.[suffix] for each of a set of several common
+/// library suffixes, in each of the directories in LibPaths. Returns an empty
+/// Path if no matching file can be found.
+///
+sys::Path
+Linker::FindLib(StringRef Filename) {
+ // Determine if the pathname can be found as it stands.
+ sys::Path FilePath(Filename);
+ if (FilePath.canRead() &&
+ (FilePath.isArchive() || FilePath.isDynamicLibrary()))
+ return FilePath;
+
+ // Iterate over the directories in Paths to see if we can find the library
+ // there.
+ for (unsigned Index = 0; Index != LibPaths.size(); ++Index) {
+ sys::Path Directory(LibPaths[Index]);
+ sys::Path FullPath = IsLibrary(Filename, Directory);
+ if (!FullPath.isEmpty())
+ return FullPath;
+ }
+ return sys::Path();
+}
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