Fix PR139: \

Implement LinkItems and BuildLinkItems interfaces.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@18547 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Linker/LinkItems.cpp

@@ -0,0 +1,159 @@
+//===- lib/Linker/LinkItems.cpp - Link LLVM objects and libraries ---------===//
+// 
+//                     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 contains routines to handle linking together LLVM bytecode files,
+// and to handle annoying things like static libraries.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Linker.h"
+#include "llvm/Module.h"
+#include "llvm/ModuleProvider.h"
+#include "llvm/PassManager.h"
+#include "llvm/ADT/SetOperations.h"
+#include "llvm/Bytecode/Reader.h"
+#include "llvm/Bytecode/Archive.h"
+#include "llvm/Bytecode/WriteBytecodePass.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Transforms/Scalar.h"
+#include "llvm/Config/config.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/FileUtilities.h"
+#include "llvm/Support/Timer.h"
+#include "llvm/System/Signals.h"
+#include "llvm/Support/SystemUtils.h"
+#include <algorithm>
+#include <fstream>
+#include <memory>
+#include <set>
+using namespace llvm;
+
+static bool 
+LinkOneLibrary(const char*progname, Module* HeadModule, 
+               const std::string& Lib, 
+               const std::vector<std::string>& LibPaths,
+               bool Verbose, bool Native) {
+
+  // String in which to receive error messages.
+  std::string ErrorMessage;
+
+  // Determine where this library lives.
+  std::string Pathname = FindLib(Lib, LibPaths);
+  if (Pathname.empty()) {
+    // If the pathname does not exist, then simply return if we're doing a 
+    // native link and give a warning if we're doing a bytecode link.
+    if (!Native) {
+      std::cerr << progname << ": error: Cannot find library '"
+                << Lib << "'\n";
+      return true;
+    }
+  }
+
+  // A user may specify an ar archive without -l, perhaps because it
+  // is not installed as a library. Detect that and link the library.
+  if (IsArchive(Pathname)) {
+    if (Verbose)
+      std::cerr << "Trying to link archive '" << Pathname << "' (-l"
+                << Lib << ")\n";
+
+    if (LinkInArchive(HeadModule, Pathname, &ErrorMessage, Verbose)) {
+      std::cerr << progname << ": " << ErrorMessage
+                << ": Error linking in archive '" << Pathname << "' (-l"
+                << Lib << ")\n";
+      return true;
+    }
+  } else {
+      std::cerr << progname << ": WARNING: Supposed library -l"
+                << Lib << " isn't a library.\n";
+  }
+  return false;
+}
+
+// LinkItems - preserve link order for an arbitrary set of linkage items.
+Module* 
+llvm::LinkItems(const char *progname, const LinkItemList& Items,
+                const std::vector<std::string>& LibPaths,
+                bool Verbose, bool Native) {
+
+  // Construct the HeadModule to contain the result of the linkage
+  std::auto_ptr<Module> HeadModule(new Module(progname));
+
+  // Construct a mutable path list we can add paths to. This list will always
+  // have LLVM_LIB_SEARCH_PATH at the end so we place it there now.
+  std::vector<std::string> MyLibPaths(LibPaths);
+  MyLibPaths.insert(MyLibPaths.begin(),".");
+  char* SearchPath = getenv("LLVM_LIB_SEARCH_PATH");
+  if (SearchPath)
+    MyLibPaths.push_back(SearchPath);
+
+  // For each linkage item ...
+  for (LinkItemList::const_iterator I = Items.begin(), E = Items.end(); 
+       I != E; ++I) {
+    if (I->second) {
+      // Link in the library suggested.
+      if (LinkOneLibrary(progname,HeadModule.get(),I->first,MyLibPaths,
+                     Verbose,Native))
+        return 0;
+    } else {
+      std::vector<std::string> Files;
+      Files.push_back(I->first);
+      if (LinkFiles(progname,HeadModule.get(),Files,Verbose))
+        return 0;
+    }
+  }
+
+  // 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.
+  const Module::LibraryListType& DepLibs = HeadModule->getLibraries();
+  for (Module::LibraryListType::const_iterator I = DepLibs.begin(), 
+      E = DepLibs.end(); I != E; ++I) {
+    if(LinkOneLibrary(progname,HeadModule.get(),*I,MyLibPaths,Verbose,Native))
+      return 0;
+  }
+
+  return HeadModule.release();
+}
+
+// BuildLinkItems -- This function
+void llvm::BuildLinkItems(
+  LinkItemList& Items,
+  const cl::list<std::string>& Files,
+  const cl::list<std::string>& Libraries) {
+
+  // Build the list of linkage items for LinkItems. 
+
+  cl::list<std::string>::const_iterator fileIt = Files.begin();
+  cl::list<std::string>::const_iterator libIt  = Libraries.begin();
+
+  int libPos = -1, filePos = -1;
+  while ( 1 ) {
+    if (libIt != Libraries.end())
+      libPos = Libraries.getPosition(libIt - Libraries.begin());
+    else
+      libPos = -1;
+    if (fileIt != Files.end())
+      filePos = Files.getPosition(fileIt - Files.begin());
+    else
+      filePos = -1;
+
+    if (filePos != -1 && (libPos == -1 || filePos < libPos)) {
+      // Add a source file
+      Items.push_back(std::make_pair(*fileIt++, false));
+    } else if (libPos != -1 && (filePos == -1 || libPos < filePos)) {
+      // Add a library
+      Items.push_back(std::make_pair(*libIt++, true));
+    } else {
+        break; // we're done with the list
+    }
+  }
+}