X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FLinker.h;h=a34980698ad96c59be6af6310f84211652afb025;hb=ccb3c9c2702f548fd0a7d60a622e6f4fdf0940e7;hp=f40cce3dcd122f15b755b324af1087928e416609;hpb=48486893f46d2e12e926682a3ecb908716bc66c4;p=oota-llvm.git

diff --git a/include/llvm/Linker.h b/include/llvm/Linker.h
index f40cce3dcd1..a34980698ad 100644
--- a/include/llvm/Linker.h
+++ b/include/llvm/Linker.h
@@ -1,21 +1,200 @@
-//===- llvm/Transforms/Utils/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 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_UTILS_LINKER_H
-#define LLVM_TRANSFORMATIONS_UTILS_LINKER_H
+#ifndef LLVM_LINKER_H
+#define LLVM_LINKER_H
 
+#include <memory>
 #include <string>
+#include <vector>
+
+namespace llvm {
+  namespace sys { class Path; }
+
 class Module;
+class LLVMContext;
+class StringRef;
 
-// 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, std::string *ErrorMsg = 0);
+/// 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.
+class Linker {
 
-#endif
+  /// @name Types
+  /// @{
+  public:
+    /// 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();
+
+  /// @}
+  /// @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 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, 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, unsigned Mode,
+                            std::string* ErrorMsg);
+
+  /// @}
+  /// @name Implementation
+  /// @{
+  private:
+    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
+  /// @}
+
+};
+
+} // End llvm namespace
+
+#endif