llvm/examples/Bye/Bye.cpp

   1 #include "llvm/IR/Function.h"
   2 #include "llvm/IR/LegacyPassManager.h"
   3 #include "llvm/Pass.h"
   4 #include "llvm/Passes/PassBuilder.h"
   5 #include "llvm/Passes/PassPlugin.h"
   6 #include "llvm/Support/CommandLine.h"
   7 #include "llvm/Support/raw_ostream.h"
   8
   9 using namespace llvm;
  10
  11 static cl::opt<bool> Wave("wave-goodbye", cl::init(false),
  12                           cl::desc("wave good bye"));
  13
  14 namespace {
  15
  16 bool runBye(Function &F) {
  17   if (Wave) {
  18     errs() << "Bye: ";
  19     errs().write_escaped(F.getName()) << '\n';
  20   }
  21   return false;
  22 }
  23
  24 struct LegacyBye : public FunctionPass {
  25   static char ID;
  26   LegacyBye() : FunctionPass(ID) {}
  27   bool runOnFunction(Function &F) override { return runBye(F); }
  28 };
  29
  30 struct Bye : PassInfoMixin<Bye> {
  31   PreservedAnalyses run(Function &F, FunctionAnalysisManager &) {
  32     if (!runBye(F))
  33       return PreservedAnalyses::all();
  34     return PreservedAnalyses::none();
  35   }
  36 };
  37
  38 } // namespace
  39
  40 char LegacyBye::ID = 0;
  41
  42 static RegisterPass<LegacyBye> X("goodbye", "Good Bye World Pass",
  43                                  false /* Only looks at CFG */,
  44                                  false /* Analysis Pass */);
  45
  46 /* New PM Registration */
  47 llvm::PassPluginLibraryInfo getByePluginInfo() {
  48   return {LLVM_PLUGIN_API_VERSION, "Bye", LLVM_VERSION_STRING,
  49           [](PassBuilder &PB) {
  50             PB.registerVectorizerStartEPCallback(
  51                 [](llvm::FunctionPassManager &PM, OptimizationLevel Level) {
  52                   PM.addPass(Bye());
  53                 });
  54             PB.registerPipelineParsingCallback(
  55                 [](StringRef Name, llvm::FunctionPassManager &PM,
  56                    ArrayRef<llvm::PassBuilder::PipelineElement>) {
  57                   if (Name == "goodbye") {
  58                     PM.addPass(Bye());
  59                     return true;
  60                   }
  61                   return false;
  62                 });
  63           }};
  64 }
  65
  66 #ifndef LLVM_BYE_LINK_INTO_TOOLS
  67 extern "C" LLVM_ATTRIBUTE_WEAK ::llvm::PassPluginLibraryInfo
  68 llvmGetPassPluginInfo() {
  69   return getByePluginInfo();
  70 }
  71 #endif