Add a trivial example plugin, which prints the names of the top-level decls.

- The build scriptage is about twice as long as the code, which is nice. :)

llvm-svn: 88826

clang/examples/PrintFunctionNames/PrintFunctionNames.cpp

@@ -0,0 +1,44 @@
+//===- PrintFunctionNames.cpp ---------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Example clang-cc plugin which simply prints the names of all the top-level
+// decls in the input file.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Frontend/FrontendPluginRegistry.h"
+#include "clang/AST/ASTConsumer.h"
+#include "clang/AST/AST.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace clang;
+
+namespace {
+
+class PrintFunctionsConsumer : public ASTConsumer {
+public:
+  virtual void HandleTopLevelDecl(DeclGroupRef DG) {
+    for (DeclGroupRef::iterator i = DG.begin(), e = DG.end(); i != e; ++i) {
+      const Decl *D = *i;
+      if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
+        llvm::errs() << "top-level-decl: \"" << ND->getNameAsString() << "\"\n";
+    }
+  }
+}; 
+
+class PrintFunctionNamesAction : public ASTFrontendAction {
+protected:
+  ASTConsumer *CreateASTConsumer(CompilerInstance &CI, llvm::StringRef) {
+    return new PrintFunctionsConsumer();
+  }
+};
+
+}
+
+FrontendPluginRegistry::Add<PrintFunctionNamesAction>
+X("print-fns", "print function names");