--- /dev/null
+//===- Hello.cpp - Example code from "Writing an LLVM Pass" ---------------===//
+//
+// This file implements two versions of the LLVM "Hello World" pass described
+// in docs/WritingAnLLVMPass.html
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Pass.h"
+#include "llvm/Function.h"
+
+namespace {
+ // Hello - The first implementation, without getAnalysisUsage.
+ struct Hello : public FunctionPass {
+ virtual bool runOnFunction(Function &F) {
+ std::cerr << "Hello: " << F.getName() << "\n";
+ return false;
+ }
+ };
+ RegisterOpt<Hello> X("hello", "Hello World Pass");
+
+ // Hello2 - The second implementation with getAnalysisUsage implemented.
+ struct Hello2 : public FunctionPass {
+ virtual bool runOnFunction(Function &F) {
+ std::cerr << "Hello: " << F.getName() << "\n";
+ return false;
+ }
+
+ // We don't modify the program, so we preserve all analyses
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.setPreservesAll();
+ };
+ };
+ RegisterOpt<Hello2> Y("hello2", "Hello World Pass (with getAnalysisUsage implemented)");
+}