X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FLinker.h;h=8c53b343924a38166d118b7b80c3cc23fe94f1c8;hb=d49e18d29f3c5622cfd373fbfa0b954d1c256455;hp=8774012f152526d1b8e0e2b424fad22ae3642d4a;hpb=4321ded265a20cb62fa5a99918dfc7d227094b8e;p=oota-llvm.git diff --git a/include/llvm/Linker.h b/include/llvm/Linker.h index 8774012f152..8c53b343924 100644 --- a/include/llvm/Linker.h +++ b/include/llvm/Linker.h @@ -1,37 +1,297 @@ -//===- llvm/Transforms/Linker.h - Module Linker Interface --------*- C++ -*--=// +//===- llvm/Linker.h - Module Linker Interface ------------------*- C++ -*-===// // -// This file defines the interface to the module linker. +// The LLVM Compiler Infrastructure +// +// This file was developed by Reid Spencer and is distributed under the +// University of Illinois Open Source License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines the interface to the module/file/archive linker. // //===----------------------------------------------------------------------===// -#ifndef LLVM_TRANSFORMATIONS_LINKER_H -#define LLVM_TRANSFORMATIONS_LINKER_H +#ifndef LLVM_LINKER_H +#define LLVM_LINKER_H + +#include "llvm/System/Path.h" +#include +#include + +namespace llvm { -#include class Module; -class Type; -class Value; +/// This class provides the core functionality of linking in LLVM. It retains a +/// Module object which is the composite of the modules and libraries linked +/// into it. The composite Module can be retrieved via the getModule() method. +/// In this case the Linker still retains ownership of the Module. If the +/// releaseModule() method is used, the ownership of the Module is transferred +/// to the caller and the Linker object is only suitable for destruction. +/// The Linker can link Modules from memory, bitcode files, or bitcode +/// archives. It retains a set of search paths in which to find any libraries +/// presented to it. By default, the linker will generate error and warning +/// messages to std::cerr but this capability can be turned off with the +/// QuietWarnings and QuietErrors flags. It can also be instructed to verbosely +/// print out the linking actions it is taking with the Verbose flag. +/// @brief The LLVM Linker. +class Linker { -// 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. -// -bool LinkModules(Module *Dest, const Module *Src, string *ErrorMsg = 0); + /// @name Types + /// @{ + public: + /// This type is used to pass the linkage items (libraries and files) to + /// the LinkItems function. It is composed of string/bool pairs. The string + /// provides the name of the file or library (as with the -l option). The + /// bool should be true for libraries and false for files, signifying + /// "isLibrary". + /// @brief A list of linkage items + typedef std::vector > ItemList; + + /// This enumeration is used to control various optional features of the + /// linker. + enum ControlFlags { + Verbose = 1, ///< Print to std::cerr what steps the linker is taking + QuietWarnings = 2, ///< Don't print errors and warnings to std::cerr. + QuietErrors = 4 ///< Indicate that this link is for a native executable + }; + + /// @} + /// @name Constructors + /// @{ + public: + /// Construct the Linker with an empty module which will be given the + /// name \p progname. \p progname will also be used for error messages. + /// @brief Construct with empty module + Linker( + const std::string& progname, ///< name of tool running linker + const std::string& modulename, ///< name of linker's end-result module + unsigned Flags = 0 ///< ControlFlags (one or more |'d together) + ); + + /// Construct the Linker with a previously defined module, \p aModule. Use + /// \p progname for the name of the program in error messages. + /// @brief Construct with existing module + Linker(const std::string& progname, Module* aModule, unsigned Flags = 0); + + /// Destruct the Linker. + /// @brief Destructor + ~Linker(); + + /// @} + /// @name Accessors + /// @{ + public: + /// This method gets the composite module into which linking is being + /// done. The Composite module starts out empty and accumulates modules + /// linked into it via the various LinkIn* methods. This method does not + /// release the Module to the caller. The Linker retains ownership and will + /// destruct the Module when the Linker is destructed. + /// @see releaseModule + /// @brief Get the linked/composite module. + Module* getModule() const { return Composite; } + + /// This method releases the composite Module into which linking is being + /// done. Ownership of the composite Module is transferred to the caller who + /// must arrange for its destruct. After this method is called, the Linker + /// terminates the linking session for the returned Module. It will no + /// longer utilize the returned Module but instead resets itself for + /// subsequent linking as if the constructor had been called. The Linker's + /// LibPaths and flags to be reset, and memory will be released. + /// @brief Release the linked/composite module. + Module* releaseModule(); + + /// This method gets the list of libraries that form the path that the + /// Linker will search when it is presented with a library name. + /// @brief Get the Linkers library path + const std::vector& getLibPaths() const { return LibPaths; } + + /// This method returns an error string suitable for printing to the user. + /// The return value will be empty unless an error occurred in one of the + /// LinkIn* methods. In those cases, the LinkIn* methods will have returned + /// true, indicating an error occurred. At most one error is retained so + /// this function always returns the last error that occurred. Note that if + /// the Quiet control flag is not set, the error string will have already + /// been printed to std::cerr. + /// @brief Get the text of the last error that occurred. + const std::string& getLastError() const { return Error; } + + /// @} + /// @name Mutators + /// @{ + public: + /// Add a path to the list of paths that the Linker will search. The Linker + /// accumulates the set of libraries added + /// library paths for the target platform. The standard libraries will + /// always be searched last. The added libraries will be searched in the + /// order added. + /// @brief Add a path. + void addPath(const sys::Path& path); + + /// Add a set of paths to the list of paths that the linker will search. The + /// Linker accumulates the set of libraries added. The \p paths will be + /// added to the end of the Linker's list. Order will be retained. + /// @brief Add a set of paths. + void addPaths(const std::vector& paths); + + /// This method augments the Linker's list of library paths with the system + /// paths of the host operating system, include LLVM_LIB_SEARCH_PATH. + /// @brief Add the system paths. + void addSystemPaths(); + + /// Control optional linker behavior by setting a group of flags. The flags + /// are defined in the ControlFlags enumeration. + /// @see ControlFlags + /// @brief Set control flags. + void setFlags(unsigned flags) { Flags = flags; } + + /// This method is the main interface to the linker. It can be used to + /// link a set of linkage items into a module. A linkage item is either a + /// file name with fully qualified path, or a library for which the Linker's + /// LibraryPath will be utilized to locate the library. The bool value in + /// the LinkItemKind should be set to true for libraries. This function + /// allows linking to preserve the order of specification associated with + /// the command line, or for other purposes. Each item will be linked in + /// turn as it occurs in \p Items. + /// @returns true if an error occurred, false otherwise + /// @see LinkItemKind + /// @see getLastError + /// @throws nothing + bool LinkInItems ( + const ItemList& Items, ///< Set of libraries/files to link in + ItemList& NativeItems ///< Output list of native files/libs + ); + + /// This function links the bitcode \p Files into the composite module. + /// Note that this does not do any linking of unresolved symbols. The \p + /// Files are all completely linked into \p HeadModule regardless of + /// unresolved symbols. This function just loads each bitcode file and + /// calls LinkInModule on them. + /// @returns true if an error occurs, false otherwise + /// @see getLastError + /// @brief Link in multiple files. + bool LinkInFiles ( + const std::vector & Files ///< Files to link in + ); + + /// This function links a single bitcode file, \p File, into the composite + /// module. Note that this does not attempt to resolve symbols. This method + /// just loads the bitcode file and calls LinkInModule on it. If an error + /// occurs, the Linker's error string is set. + /// @returns true if an error occurs, false otherwise + /// @see getLastError + /// @brief Link in a single file. + bool LinkInFile( + const sys::Path& File, ///< File to link in. + bool &is_native ///< Indicates if the file is native object file + ); + + /// This function provides a way to selectively link in a set of modules, + /// found in libraries, based on the unresolved symbols in the composite + /// module. Each item in \p Libraries should be the base name of a library, + /// as if given with the -l option of a linker tool. The Linker's LibPaths + /// are searched for the \p Libraries and any found will be linked in with + /// LinkInArchive. If an error occurs, the Linker's error string is set. + /// @see LinkInArchive + /// @see getLastError + /// @returns true if an error occurs, false otherwise + /// @brief Link libraries into the module + bool LinkInLibraries ( + const std::vector & Libraries ///< Libraries to link in + ); + + /// This function provides a way to selectively link in a set of modules, + /// found in one library, based on the unresolved symbols in the composite + /// module.The \p Library should be the base name of a library, as if given + /// with the -l option of a linker tool. The Linker's LibPaths are searched + /// for the \p Library and if found, it will be linked in with via the + /// LinkInArchive method. If an error occurs, the Linker's error string is + /// set. + /// @see LinkInArchive + /// @see getLastError + /// @returns true if an error occurs, false otherwise + /// @brief Link one library into the module + bool LinkInLibrary ( + const std::string& Library, ///< The library to link in + bool& is_native ///< Indicates if lib a native library + ); + + /// This function links one bitcode archive, \p Filename, into the module. + /// The archive is searched to resolve outstanding symbols. Any modules in + /// the archive that resolve outstanding symbols will be linked in. The + /// library is searched repeatedly until no more modules that resolve + /// symbols can be found. If an error occurs, the error string is set. + /// To speed up this function, ensure the the archive has been processed + /// llvm-ranlib or the S option was given to llvm-ar when the archive was + /// created. These tools add a symbol table to the archive which makes the + /// search for undefined symbols much faster. + /// @see getLastError + /// @returns true if an error occurs, otherwise false. + /// @brief Link in one archive. + bool LinkInArchive( + const sys::Path& Filename, ///< Filename of the archive to link + bool& is_native ///< Indicates if archive is a native archive + ); + + /// This method links the \p Src module into the Linker's Composite module + /// by calling LinkModules. All the other LinkIn* methods eventually + /// result in calling this method to link a Module into the Linker's + /// composite. + /// @see LinkModules + /// @returns True if an error occurs, false otherwise. + /// @brief Link in a module. + bool LinkInModule( + Module* Src, ///< Module linked into \p Dest + std::string* ErrorMsg = 0 /// Error/diagnostic string + ) { + return LinkModules(Composite, Src, ErrorMsg ); + } + + /// This is the heart of the linker. This method will take unconditional + /// control of the \p Src module and link it into the \p Dest module. The + /// \p Src module will be destructed or subsumed by this method. In either + /// case it is not usable by the caller after this method is invoked. Only + /// the \p Dest module will remain. The \p Src module is linked into the + /// Linker's composite module such that types, global variables, functions, + /// and etc. are matched and resolved. If an error occurs, this function + /// returns true and ErrorMsg is set to a descriptive message about the + /// error. + /// @returns True if an error occurs, false otherwise. + /// @brief Generically link two modules together. + static bool LinkModules(Module* Dest, Module* Src, std::string* ErrorMsg); + + /// This function looks through the Linker's LibPaths to find a library with + /// the name \p Filename. If the library cannot be found, the returned path + /// will be empty (i.e. sys::Path::isEmpty() will return true). + /// @returns A sys::Path to the found library + /// @brief Find a library from its short name. + sys::Path FindLib(const std::string &Filename); + /// @} + /// @name Implementation + /// @{ + private: + /// Read in and parse the bitcode file named by FN and return the + /// Module it contains (wrapped in an auto_ptr), or 0 if an error occurs. + std::auto_ptr LoadObject(const sys::Path& FN); -// MangleTypeName - Implement a consistent name-mangling scheme for -// a given type. -// -string MangleTypeName(const Type* type); + bool warning(const std::string& message); + bool error(const std::string& message); + void verbose(const std::string& message); + /// @} + /// @name Data + /// @{ + private: + Module* Composite; ///< The composite module linked together + std::vector LibPaths; ///< The library search paths + unsigned Flags; ///< Flags to control optional behavior. + std::string Error; ///< Text of error that occurred. + std::string ProgramName; ///< Name of the program being linked + /// @} -// MangleName - implement a consistent name-mangling scheme for all -// externally visible (i.e., global) objects. -// privateName should be unique within the module. -// -string MangleName(const string& privateName, const Value* V); +}; +} // End llvm namespace #endif