Merge pull request #432 from john03690248/lab6

[LAB6] 313560003

Author: YingMuo

lab6/llvm-pass.so.cc

@@ -1,34 +1,71 @@
 #include "llvm/Passes/PassPlugin.h"
 #include "llvm/Passes/PassBuilder.h"
 #include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/Support/raw_ostream.h"
 
 using namespace llvm;
 
+bool registerCustomPipeline(StringRef, ModulePassManager&, ArrayRef<PassBuilder::PipelineElement>);
+void injectAtStart(ModulePassManager&, OptimizationLevel);
+
+namespace {
 struct LLVMPass : public PassInfoMixin<LLVMPass> {
-  PreservedAnalyses run(Module &M, ModuleAnalysisManager &MAM);
-};
+  PreservedAnalyses run(Module &Mod, ModuleAnalysisManager &) {
+    Function *MainFunc = Mod.getFunction("main");
+    if (!MainFunc) return PreservedAnalyses::all();
+
+    LLVMContext &Context = Mod.getContext();
+    IRBuilder<> Builder(&*MainFunc->getEntryBlock().getFirstInsertionPt());
+
+    FunctionCallee DebugCall = Mod.getOrInsertFunction(
+        "debug", FunctionType::get(Type::getVoidTy(Context), {Type::getInt32Ty(Context)}, false));
+    Builder.CreateCall(DebugCall, ConstantInt::get(Type::getInt32Ty(Context), 48763));
+
+    auto ArgIter = MainFunc->arg_begin();
+    Argument *ArgCount = &*ArgIter++;
+    Argument *ArgList = &*ArgIter;
+
+    Value *FixedVal = ConstantInt::get(Type::getInt32Ty(Context), 48763);
+    AllocaInst *FakeArgc = Builder.CreateAlloca(Type::getInt32Ty(Context), nullptr, "argc_temp");
+    Builder.CreateStore(FixedVal, FakeArgc);
 
-PreservedAnalyses LLVMPass::run(Module &M, ModuleAnalysisManager &MAM) {
-  LLVMContext &Ctx = M.getContext();
-  IntegerType *Int32Ty = IntegerType::getInt32Ty(Ctx);
-  FunctionCallee debug_func = M.getOrInsertFunction("debug", Int32Ty);
-  ConstantInt *debug_arg = ConstantInt::get(Int32Ty, 48763);
+    for (auto UI = ArgCount->use_begin(), UE = ArgCount->use_end(); UI != UE;) {
+      Use &U = *UI++;
+      U.set(Builder.CreateLoad(Type::getInt32Ty(Context), FakeArgc));
+    }
 
-  for (auto &F : M) {
-    errs() << "func: " << F.getName() << "\n";
+    Value *Str = Builder.CreateGlobalStringPtr("hayaku... motohayaku!", "msg_str");
+    Value *Index = ConstantInt::get(Type::getInt32Ty(Context), 1);
+    Value *ArgvSlot = Builder.CreateGEP(
+        ArgList->getType()->getPointerElementType(), ArgList, Index);
+    Builder.CreateStore(Str, ArgvSlot);
 
+    return PreservedAnalyses::none();
   }
-  return PreservedAnalyses::none();
+};
 }
 
-extern "C" ::llvm::PassPluginLibraryInfo LLVM_ATTRIBUTE_WEAK
-llvmGetPassPluginInfo() {
-  return {LLVM_PLUGIN_API_VERSION, "LLVMPass", "1.0",
+extern "C" LLVM_ATTRIBUTE_WEAK ::llvm::PassPluginLibraryInfo llvmGetPassPluginInfo() {
+  static const PassPluginLibraryInfo Info{
+    LLVM_PLUGIN_API_VERSION, "LLVMPass", LLVM_VERSION_STRING,
     [](PassBuilder &PB) {
-      PB.registerOptimizerLastEPCallback(
-        [](ModulePassManager &MPM, OptimizationLevel OL) {
-          MPM.addPass(LLVMPass());
-        });
-    }};
+      PB.registerPipelineParsingCallback(registerCustomPipeline);
+      PB.registerPipelineStartEPCallback(injectAtStart);
+    }
+  };
+  return Info;
 }
 
+bool registerCustomPipeline(StringRef Name, ModulePassManager &PM, ArrayRef<PassBuilder::PipelineElement>) {
+  if (Name == "llvm-pass") {
+    PM.addPass(LLVMPass());
+    return true;
+  }
+  return false;
+}
+
+void injectAtStart(ModulePassManager &PM, OptimizationLevel) {
+  PM.addPass(LLVMPass());
+}