Merge pull request #474 from skysoul1024/lab6

[LAB6] 313551109

Author: YingMuo

lab6/llvm-pass.so.cc

@@ -1,6 +1,7 @@
 #include "llvm/Passes/PassPlugin.h"
 #include "llvm/Passes/PassBuilder.h"
 #include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Constants.h"
 
 using namespace llvm;
 
@@ -11,13 +12,39 @@ struct LLVMPass : public PassInfoMixin<LLVMPass> {
 PreservedAnalyses LLVMPass::run(Module &M, ModuleAnalysisManager &MAM) {
   LLVMContext &Ctx = M.getContext();
   IntegerType *Int32Ty = IntegerType::getInt32Ty(Ctx);
-  FunctionCallee debug_func = M.getOrInsertFunction("debug", Int32Ty);
+  PointerType *CharPtrTy = Type::getInt8PtrTy(Ctx);
+  
+  // Get or create debug function declaration
+  FunctionCallee debug_func = M.getOrInsertFunction("debug", 
+    FunctionType::get(Type::getVoidTy(Ctx), {Int32Ty}, false));
+  
+  // Create constant value for debug function argument and argc
   ConstantInt *debug_arg = ConstantInt::get(Int32Ty, 48763);
-
+  
   for (auto &F : M) {
-    errs() << "func: " << F.getName() << "\n";
-
+    // Find main function
+    if (F.getName() == "main") {
+      // Create IRBuilder at the beginning of the entry block
+      IRBuilder<> Builder(&*F.getEntryBlock().getFirstInsertionPt());
+      
+      // a. Call debug function with argument 48763
+      Builder.CreateCall(debug_func, {debug_arg});
+      
+      // Get function arguments
+      Argument *argcArg = F.getArg(0);
+      Argument *argvArg = F.getArg(1);
+      
+      // b. Set argv[1] = "hayaku... motohayaku!"
+      Value *index1 = ConstantInt::get(Int32Ty, 1);
+      Value *argv1_ptr = Builder.CreateInBoundsGEP(CharPtrTy, argvArg, index1);
+      Value *hayakuStr = Builder.CreateGlobalStringPtr("hayaku... motohayaku!");
+      Builder.CreateStore(hayakuStr, argv1_ptr);
+      
+      // c. Replace all uses of argc with 48763
+      argcArg->replaceAllUsesWith(debug_arg);
+    }
   }
+  
   return PreservedAnalyses::none();
 }
 
@@ -30,5 +57,4 @@ llvmGetPassPluginInfo() {
           MPM.addPass(LLVMPass());
         });
     }};
-}
-
+}