// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
-//
-// This file defines the interface to the module/file/archive linker.
-//
-//===----------------------------------------------------------------------===//
#ifndef LLVM_LINKER_H
#define LLVM_LINKER_H
-#include <memory>
-#include <vector>
-#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include <string>
namespace llvm {
- namespace sys { class Path; }
class Module;
-class LLVMContext;
+class StringRef;
+class StructType;
-/// 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 stderr 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.
+/// This class provides the core functionality of linking in LLVM. It keeps a
+/// pointer to the merged module so far. It doesn't take ownership of the
+/// module since it is assumed that the user of this class will want to do
+/// something with it after the linking.
class Linker {
-
- /// @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<std::pair<std::string,bool> > ItemList;
-
- /// This enumeration is used to control various optional features of the
- /// linker.
- enum ControlFlags {
- Verbose = 1, ///< Print to stderr what steps the linker is taking
- QuietWarnings = 2, ///< Don't print warnings to stderr.
- QuietErrors = 4 ///< Don't print errors to stderr.
+ enum LinkerMode {
+ DestroySource = 0, // Allow source module to be destroyed.
+ PreserveSource = 1 // Preserve the source module.
};
- /// @}
- /// @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(StringRef progname, ///< name of tool running linker
- StringRef modulename, ///< name of linker's end-result module
- LLVMContext &C, ///< Context for global info
- 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(StringRef progname, Module* aModule, unsigned Flags = 0);
-
- /// Destruct the Linker.
- /// @brief Destructor
+ Linker(Module *M);
~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<sys::Path>& 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 stderr.
- /// @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<std::string>& 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<sys::Path> & 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<std::string> & 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 (
- StringRef 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 );
+ Module *getModule() const { return Composite; }
+ void deleteModule();
+
+ /// \brief Link \p Src into the composite. The source is destroyed if
+ /// \p Mode is DestroySource and preserved if it is PreserveSource.
+ /// If \p ErrorMsg is not null, information about any error is written
+ /// to it.
+ /// Returns true on error.
+ bool linkInModule(Module *Src, unsigned Mode, std::string *ErrorMsg);
+ bool linkInModule(Module *Src, std::string *ErrorMsg) {
+ return linkInModule(Src, Linker::DestroySource, 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);
+ static bool LinkModules(Module *Dest, Module *Src, unsigned Mode,
+ 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(StringRef 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<Module> LoadObject(const sys::Path& FN);
-
- bool warning(StringRef message);
- bool error(StringRef message);
- void verbose(StringRef message);
-
- /// @}
- /// @name Data
- /// @{
- private:
- LLVMContext& Context; ///< The context for global information
- Module* Composite; ///< The composite module linked together
- std::vector<sys::Path> 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
- /// @}
-
+ Module *Composite;
+ SmallPtrSet<StructType*, 32> IdentifiedStructTypes;
};
} // End llvm namespace