Reorganize llvmc code.

Move the code from 'llvmc/driver' into a new CompilerDriver library, and change
the build system accordingly. Makes it easier for projects using LLVM to build
their own llvmc-based drivers.

Tested with objdir != srcdir.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65821 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CompilerDriver/Plugin.cpp

@@ -0,0 +1,73 @@
+//===--- Plugin.cpp - The LLVM Compiler Driver ------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open
+// Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  Plugin support.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CompilerDriver/Plugin.h"
+
+#include <algorithm>
+#include <vector>
+
+namespace {
+
+  // Registry::Add<> does not do lifetime management (probably issues
+  // with static constructor/destructor ordering), so we have to
+  // implement it here.
+  //
+  // All this static registration/life-before-main model seems
+  // unnecessary convoluted to me.
+
+  static bool pluginListInitialized = false;
+  typedef std::vector<const llvmc::BasePlugin*> PluginList;
+  static PluginList Plugins;
+
+  struct ByPriority {
+    bool operator()(const llvmc::BasePlugin* lhs,
+                    const llvmc::BasePlugin* rhs) {
+      return lhs->Priority() < rhs->Priority();
+    }
+  };
+}
+
+namespace llvmc {
+
+  PluginLoader::PluginLoader() {
+    if (!pluginListInitialized) {
+      for (PluginRegistry::iterator B = PluginRegistry::begin(),
+             E = PluginRegistry::end(); B != E; ++B)
+        Plugins.push_back(B->instantiate());
+      std::sort(Plugins.begin(), Plugins.end(), ByPriority());
+    }
+    pluginListInitialized = true;
+  }
+
+  PluginLoader::~PluginLoader() {
+    if (pluginListInitialized) {
+      for (PluginList::iterator B = Plugins.begin(), E = Plugins.end();
+           B != E; ++B)
+        delete (*B);
+    }
+    pluginListInitialized = false;
+  }
+
+  void PluginLoader::PopulateLanguageMap(LanguageMap& langMap) {
+    for (PluginList::iterator B = Plugins.begin(), E = Plugins.end();
+         B != E; ++B)
+      (*B)->PopulateLanguageMap(langMap);
+  }
+
+  void PluginLoader::PopulateCompilationGraph(CompilationGraph& graph) {
+    for (PluginList::iterator B = Plugins.begin(), E = Plugins.end();
+         B != E; ++B)
+      (*B)->PopulateCompilationGraph(graph);
+  }
+
+}