fix: lab8 no angr

Author: YingMuo

.github/workflows/lab-autograding.yml

@@ -56,4 +56,7 @@ jobs:
                   if [ ${{ steps.lab.outputs.result }} -eq 6 ]; then
                     sudo apt install -y llvm-14
                   fi
+                  if [ ${{ steps.lab.outputs.result }} -eq 8 ]; then
+                    python3 -m pip install angr
+                  fi
                   ./validate.sh

lab6/llvm-pass.so.cc

@@ -14,39 +14,11 @@ PreservedAnalyses LLVMPass::run(Module &M, ModuleAnalysisManager &MAM) {
   FunctionCallee debug_func = M.getOrInsertFunction("debug", Int32Ty);
   ConstantInt *debug_arg = ConstantInt::get(Int32Ty, 48763);
 
-  bool Modified = false;
-
   for (auto &F : M) {
     errs() << "func: " << F.getName() << "\n";
 
-    if (F.getName() != "main") continue;
-    BasicBlock &EntryBB = F.getEntryBlock();
-    IRBuilder<> Builder(&*EntryBB.getFirstInsertionPt());
-    // 1：Insert debug(48763)
-    Builder.CreateCall(debug_func, {debug_arg});
-
-    // 2：Set argv[1] to "hayaku... motohayaku!"
-    Constant *StrConst = ConstantDataArray::getString(Ctx, "hayaku... motohayaku!");
-    GlobalVariable *StrVar = new GlobalVariable(
-        M, StrConst->getType(), true, GlobalValue::PrivateLinkage, StrConst, ".str");
-    Constant *StrPtr = ConstantExpr::getPointerCast(StrVar, Type::getInt8PtrTy(Ctx));
-
-    // Get argv[1]
-    Value *Argv = F.getArg(1);
-    // Calculate the address of argv[1]（argv + 1）
-    Value *Argv1Ptr = Builder.CreateGEP(Type::getInt8PtrTy(Ctx), Argv,
-                                       ConstantInt::get(Type::getInt64Ty(Ctx), 1));
-    // Set argv[1] to new string
-    Builder.CreateStore(StrPtr, Argv1Ptr);
-
-    // 3：Set argc to 48763
-    Value *Argc = F.getArg(0);
-    Value *ArgcPtr = Builder.CreateAlloca(Int32Ty, nullptr, "argc.ptr");
-    Builder.CreateStore(debug_arg, ArgcPtr);
-    Argc->replaceAllUsesWith(Builder.CreateLoad(Int32Ty, ArgcPtr));
-    Modified = true;
   }
-  return Modified ? PreservedAnalyses::none() : PreservedAnalyses::all();
+  return PreservedAnalyses::none();
 }
 
 extern "C" ::llvm::PassPluginLibraryInfo LLVM_ATTRIBUTE_WEAK