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 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
   9
  10 using namespace llvm;
  11
  12 static cl::opt<bool> Wave("wave-goodbye", cl::init(false),
  13                           cl::desc("wave good bye"));
  14
  15 namespace {
  16
  17 bool runBye(Function &F) {
  18   if (Wave) {
  19     errs() << "Bye: ";
  20     errs().write_escaped(F.getName()) << '\n';
  21   }
  22   return false;
  23 }
  24
  25 struct LegacyBye : public FunctionPass {
  26   static char ID;
  27   LegacyBye() : FunctionPass(ID) {}
  28   bool runOnFunction(Function &F) override { return runBye(F); }
  29 };
  30
  31 struct Bye : PassInfoMixin<Bye> {
  32   PreservedAnalyses run(Function &F, FunctionAnalysisManager &) {
  33     if (!runBye(F))
  34       return PreservedAnalyses::all();
  35     return PreservedAnalyses::none();
  36   }
  37 };
  38
  39 } // namespace
  40
  41 char LegacyBye::ID = 0;
  42
  43 static RegisterPass<LegacyBye> X("goodbye", "Good Bye World Pass",
  44                                  false /* Only looks at CFG */,
  45                                  false /* Analysis Pass */);
  46
  47 /* Legacy PM Registration */
  48 static llvm::RegisterStandardPasses RegisterBye(
  49     llvm::PassManagerBuilder::EP_VectorizerStart,
  50     [](const llvm::PassManagerBuilder &Builder,
  51        llvm::legacy::PassManagerBase &PM) { PM.add(new LegacyBye()); });
  52
  53 /* New PM Registration */
  54 llvm::PassPluginLibraryInfo getByePluginInfo() {
  55   return {LLVM_PLUGIN_API_VERSION, "Bye", LLVM_VERSION_STRING,
  56           [](PassBuilder &PB) {
  57             PB.registerVectorizerStartEPCallback(
  58                 [](llvm::FunctionPassManager &PM, OptimizationLevel Level) {
  59                   PM.addPass(Bye());
  60                 });
  61             PB.registerPipelineParsingCallback(
  62                 [](StringRef Name, llvm::FunctionPassManager &PM,
  63                    ArrayRef<llvm::PassBuilder::PipelineElement>) {
  64                   if (Name == "goodbye") {
  65                     PM.addPass(Bye());
  66                     return true;
  67                   }
  68                   return false;
  69                 });
  70           }};
  71 }
  72
  73 #ifndef LLVM_BYE_LINK_INTO_TOOLS
  74 extern "C" LLVM_ATTRIBUTE_WEAK ::llvm::PassPluginLibraryInfo
  75 llvmGetPassPluginInfo() {
  76   return getByePluginInfo();
  77 }
  78 #endif