Add a way to access argv[0] in hooks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74483 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CompilerDriver/Main.cpp

@@ -71,11 +71,16 @@ namespace {
 
 namespace llvmc {
 
+// Sometimes plugins want to condition on the value in argv[0].
+const char* ProgramName;
+
 int Main(int argc, char** argv) {
   try {
     LanguageMap langMap;
     CompilationGraph graph;
 
+    ProgramName = argv[0];
+
     cl::ParseCommandLineOptions
       (argc, argv, "LLVM Compiler Driver (Work In Progress)", true);