Initial checkin of the "Hello World" Pass.

llvm-svn: 3266

1 files changed, 34 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Hello/Hello.cpp b/llvm/lib/Transforms/Hello/Hello.cpp
new file mode 100644
index 0000000..6ca450f
--- /dev/null
+++ b/llvm/lib/Transforms/Hello/Hello.cpp
@@ -0,0 +1,34 @@
+//===- 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)");
+}