LLVM入门与CSCD70的Assignments

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llvm

Tutorial2 introduction to LLVM Ⅱ

操作基本指令依靠 instruction class, basic block class or BasicBlockUtils class。

User-Use-Value

我们如何确保所有引用（i.e. uses）会被正确的更新？User-Use-Value relationship 用来解决这个问题。

LLVM 有一个很重要的基类：Value。几乎所有的 object types 都是继承于此。

Assignment1

Function Information

FunctionInfoPass 中的 run 函数的 todo 部分：

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PreservedAnalyses run(Module &M, ModuleAnalysisManager &) {
    outs() << "CSCD70 Function Information Pass"
    << "\n";

    /// @todo(CSCD70) Please complete this method.
    for (auto iter = M.begin(); iter != M.end(); ++iter) {
        Function &func = *iter;
        outs() << "Function name: " << func.getName() << "\n";
        outs() << "Number of Arguments: " << func.arg_size() << "\n";
        outs() << "Number of Calls: " << func.getNumUses() << "\n";
        outs() << "Number OF BBs: " << func.size() << "\n";
        int funcInstrSize = 0;
        for (BasicBlock &BB : func) {
            funcInstrSize += BB.size();
        }
        outs() << "Number of Instructions: " << funcInstrSize << "\n\n";
    }

    return PreservedAnalyses::all();
}
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$ clang -O0 -emit-llvm -c ./test/Loop.c -o ./test/Loop.bc
$ opt -load-pass-plugin=./libFunctionInfo.so -passes=function-info ./test/Loop.bc -o ./test/LoopFunctionInfo.bc

参考文章

  1. 代码优化与LLVM IR pass | Kiprey’s Blog
  2. eternalsakura/sakura_llvm_opt: 15-745 note (github.com)
  3. About — LLVM 17.0.0git documentation
  4. UofT-EcoSystem/CSCD70: CSCD70 Compiler Optimization (github.com)