[midend]重构了src目录
This commit is contained in:
Lixuanwang
600
src/midend/Pass/Optimize/SysYIRCFGOpt.cpp
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600
src/midend/Pass/Optimize/SysYIRCFGOpt.cpp
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#include "SysYIRCFGOpt.h"
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#include "SysYIROptUtils.h"
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#include <cassert>
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#include <list>
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#include <map>
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#include <memory>
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#include <string>
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#include <iostream>
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#include <queue> // 引入队列，SysYDelNoPreBLock需要
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namespace sysy {
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// 定义静态ID
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void *SysYDelInstAfterBrPass::ID = (void *)&SysYDelInstAfterBrPass::ID;
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void *SysYDelEmptyBlockPass::ID = (void *)&SysYDelEmptyBlockPass::ID;
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void *SysYDelNoPreBLockPass::ID = (void *)&SysYDelNoPreBLockPass::ID;
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void *SysYBlockMergePass::ID = (void *)&SysYBlockMergePass::ID;
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void *SysYAddReturnPass::ID = (void *)&SysYAddReturnPass::ID;
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void *SysYCondBr2BrPass::ID = (void *)&SysYCondBr2BrPass::ID;
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// ======================================================================
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// SysYCFGOptUtils: 辅助工具类，包含实际的CFG优化逻辑
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// ======================================================================
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// 删除br后的无用指令
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bool SysYCFGOptUtils::SysYDelInstAfterBr(Function *func) {
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bool changed = false;
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auto basicBlocks = func->getBasicBlocks();
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for (auto &basicBlock : basicBlocks) {
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bool Branch = false;
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auto &instructions = basicBlock->getInstructions();
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auto Branchiter = instructions.end();
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for (auto iter = instructions.begin(); iter != instructions.end(); ++iter) {
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if ((*iter)->isTerminator()){
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Branch = true;
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Branchiter = iter;
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break;
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}
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}
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if (Branchiter != instructions.end()) ++Branchiter;
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while (Branchiter != instructions.end()) {
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changed = true;
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Branchiter = instructions.erase(Branchiter);
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}
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if (Branch) { // 更新前驱后继关系
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auto thelastinstinst = basicBlock->getInstructions().end();
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--thelastinstinst;
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auto &Successors = basicBlock->getSuccessors();
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for (auto iterSucc = Successors.begin(); iterSucc != Successors.end();) {
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(*iterSucc)->removePredecessor(basicBlock.get());
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basicBlock->removeSuccessor(*iterSucc);
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}
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if (thelastinstinst->get()->isUnconditional()) {
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BasicBlock* branchBlock = dynamic_cast<BasicBlock *>(thelastinstinst->get()->getOperand(0));
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basicBlock->addSuccessor(branchBlock);
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branchBlock->addPredecessor(basicBlock.get());
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} else if (thelastinstinst->get()->isConditional()) {
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BasicBlock* thenBlock = dynamic_cast<BasicBlock *>(thelastinstinst->get()->getOperand(1));
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BasicBlock* elseBlock = dynamic_cast<BasicBlock *>(thelastinstinst->get()->getOperand(2));
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basicBlock->addSuccessor(thenBlock);
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basicBlock->addSuccessor(elseBlock);
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thenBlock->addPredecessor(basicBlock.get());
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elseBlock->addPredecessor(basicBlock.get());
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}
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}
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}
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return changed;
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}
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// 合并基本块
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bool SysYCFGOptUtils::SysYBlockMerge(Function *func) {
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bool changed = false;
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for (auto blockiter = func->getBasicBlocks().begin();
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blockiter != func->getBasicBlocks().end();) {
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if (blockiter->get()->getNumSuccessors() == 1) {
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// 如果当前块只有一个后继块
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// 且后继块只有一个前驱块
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// 则将当前块和后继块合并
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if (((blockiter->get())->getSuccessors()[0])->getNumPredecessors() == 1) {
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// std::cout << "merge block: " << blockiter->get()->getName() << std::endl;
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BasicBlock* block = blockiter->get();
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BasicBlock* nextBlock = blockiter->get()->getSuccessors()[0];
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// auto nextarguments = nextBlock->getArguments();
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// 删除br指令
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if (block->getNumInstructions() != 0) {
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auto thelastinstinst = block->end();
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(--thelastinstinst);
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if (thelastinstinst->get()->isUnconditional()) {
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SysYIROptUtils::usedelete(thelastinstinst->get());
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thelastinstinst = block->getInstructions().erase(thelastinstinst);
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} else if (thelastinstinst->get()->isConditional()) {
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// 如果是条件分支，判断条件是否相同，主要优化相同布尔表达式
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if (thelastinstinst->get()->getOperand(1)->getName() == thelastinstinst->get()->getOperand(1)->getName()) {
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SysYIROptUtils::usedelete(thelastinstinst->get());
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thelastinstinst = block->getInstructions().erase(thelastinstinst);
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}
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}
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}
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// 将后继块的指令移动到当前块
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// 并将后继块的父指针改为当前块
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for (auto institer = nextBlock->begin(); institer != nextBlock->end();) {
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institer->get()->setParent(block);
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block->getInstructions().emplace_back(institer->release());
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institer = nextBlock->getInstructions().erase(institer);
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}
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// 更新前驱后继关系，类似树节点操作
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block->removeSuccessor(nextBlock);
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nextBlock->removePredecessor(block);
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std::list<BasicBlock *> succshoulddel;
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for (auto &succ : nextBlock->getSuccessors()) {
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block->addSuccessor(succ);
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succ->replacePredecessor(nextBlock, block);
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succshoulddel.push_back(succ);
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}
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for (auto del : succshoulddel) {
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nextBlock->removeSuccessor(del);
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}
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func->removeBasicBlock(nextBlock);
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changed = true;
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} else {
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blockiter++;
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}
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} else {
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blockiter++;
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}
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}
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return changed;
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}
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// 删除无前驱块，兼容SSA后的处理
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bool SysYCFGOptUtils::SysYDelNoPreBLock(Function *func) {
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bool changed = false;
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for (auto &block : func->getBasicBlocks()) {
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block->setreachableFalse();
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}
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// 对函数基本块做一个拓扑排序，排查不可达基本块
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auto entryBlock = func->getEntryBlock();
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entryBlock->setreachableTrue();
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std::queue<BasicBlock *> blockqueue;
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blockqueue.push(entryBlock);
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while (!blockqueue.empty()) {
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auto block = blockqueue.front();
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blockqueue.pop();
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for (auto &succ : block->getSuccessors()) {
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if (!succ->getreachable()) {
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succ->setreachableTrue();
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blockqueue.push(succ);
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}
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}
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}
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// 删除不可达基本块指令
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for (auto blockIter = func->getBasicBlocks().begin(); blockIter != func->getBasicBlocks().end(); blockIter++) {
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if (!blockIter->get()->getreachable()) {
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for (auto instIter = blockIter->get()->getInstructions().begin();
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instIter != blockIter->get()->getInstructions().end();) {
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SysYIROptUtils::usedelete(instIter->get());
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instIter = blockIter->get()->getInstructions().erase(instIter);
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}
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}
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}
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for (auto blockIter = func->getBasicBlocks().begin(); blockIter != func->getBasicBlocks().end();) {
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if (!blockIter->get()->getreachable()) {
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for (auto succblock : blockIter->get()->getSuccessors()) {
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for (auto &phiinst : succblock->getInstructions()) {
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if (phiinst->getKind() != Instruction::kPhi) {
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break;
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}
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// 使用 delBlk 方法正确地删除对应于被删除基本块的传入值
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dynamic_cast<PhiInst *>(phiinst.get())->delBlk(blockIter->get());
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}
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}
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// 删除不可达基本块，注意迭代器不可达问题
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func->removeBasicBlock((blockIter++)->get());
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changed = true;
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} else {
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blockIter++;
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}
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}
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return changed;
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}
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// 删除空块
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bool SysYCFGOptUtils::SysYDelEmptyBlock(Function *func, IRBuilder* pBuilder) {
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bool changed = false;
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// 收集不可达基本块
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// 这里的不可达基本块是指没有实际指令的基本块
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// 当一个基本块没有实际指令例如只有phi指令和一个uncondbr指令时，也会被视作不可达
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auto basicBlocks = func->getBasicBlocks();
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std::map<sysy::BasicBlock *, BasicBlock *> EmptyBlocks;
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// 空块儿和后继的基本块的映射
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for (auto &basicBlock : basicBlocks) {
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if (basicBlock->getNumInstructions() == 0) {
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if (basicBlock->getNumSuccessors() == 1) {
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EmptyBlocks[basicBlock.get()] = basicBlock->getSuccessors().front();
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}
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}
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else{
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// 如果只有phi指令和一个uncondbr。(phi)*(uncondbr)?
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// 判断除了最后一个指令之外是不是只有phi指令
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bool onlyPhi = true;
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for (auto &inst : basicBlock->getInstructions()) {
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if (!inst->isPhi() && !inst->isUnconditional()) {
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onlyPhi = false;
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break;
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}
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}
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if(onlyPhi && basicBlock->getNumSuccessors() == 1) // 确保有后继且只有一个
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EmptyBlocks[basicBlock.get()] = basicBlock->getSuccessors().front();
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}
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}
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// 更新基本块信息，增加必要指令
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for (auto &basicBlock : basicBlocks) {
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// 把空块转换成只有跳转指令的不可达块 (这段逻辑在优化遍中可能需要调整，这里是原样保留)
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// 通常，DelEmptyBlock 应该在BlockMerge之后运行，如果存在完全空块，它会尝试填充一个Br指令。
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// 但是，它主要目的是重定向跳转。
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if (distance(basicBlock->begin(), basicBlock->end()) == 0) {
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if (basicBlock->getNumSuccessors() == 0) {
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continue;
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}
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if (basicBlock->getNumSuccessors() > 1) {
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// 如果一个空块有多个后继，说明CFG结构有问题或者需要特殊处理，这里简单assert
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assert(false && "Empty block with multiple successors found during SysYDelEmptyBlock");
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}
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// 这里的逻辑有点问题，如果一个块是空的，且只有一个后继，应该直接跳转到后继。
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// 如果这个块最终被删除了，那么其前驱也需要重定向。
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// 这个循环的目的是重定向现有的跳转指令，而不是创建新的。
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// 所以下面的逻辑才是核心。
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// pBuilder->setPosition(basicBlock.get(), basicBlock->end());
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// pBuilder->createUncondBrInst(basicBlock->getSuccessors()[0], {});
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continue;
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}
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auto thelastinst = basicBlock->getInstructions().end();
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--thelastinst;
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// 根据br指令传递的后继块信息，跳过空块链
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if (thelastinst->get()->isUnconditional()) {
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BasicBlock* OldBrBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
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BasicBlock *thelastBlockOld = nullptr;
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// 如果空块链表为多个块
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while (EmptyBlocks.count(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0)))) {
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thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
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thelastinst->get()->replaceOperand(0, EmptyBlocks[thelastBlockOld]);
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}
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// 如果有重定向发生
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if (thelastBlockOld != nullptr) {
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basicBlock->removeSuccessor(OldBrBlock);
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OldBrBlock->removePredecessor(basicBlock.get());
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basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0)));
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dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->addPredecessor(basicBlock.get());
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changed = true; // 标记IR被修改
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}
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if (thelastBlockOld != nullptr) {
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for (auto &InstInNew : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->getInstructions()) {
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if (InstInNew->isPhi()) {
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// 使用 delBlk 方法删除 oldBlock 对应的传入值
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dynamic_cast<PhiInst *>(InstInNew.get())->delBlk(thelastBlockOld);
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} else {
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break;
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}
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}
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}
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} else if (thelastinst->get()->getKind() == Instruction::kCondBr) {
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auto OldThenBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1));
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auto OldElseBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2));
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bool thenChanged = false;
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bool elseChanged = false;
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BasicBlock *thelastBlockOld = nullptr;
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while (EmptyBlocks.count(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)))) {
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thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1));
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thelastinst->get()->replaceOperand(
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1, EmptyBlocks[dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))]);
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thenChanged = true;
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}
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if (thenChanged) {
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basicBlock->removeSuccessor(OldThenBlock);
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OldThenBlock->removePredecessor(basicBlock.get());
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basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)));
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dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))->addPredecessor(basicBlock.get());
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changed = true; // 标记IR被修改
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}
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// 处理 then 和 else 分支合并的情况
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if (dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)) ==
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dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))) {
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auto thebrBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1));
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SysYIROptUtils::usedelete(thelastinst->get());
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thelastinst = basicBlock->getInstructions().erase(thelastinst);
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pBuilder->setPosition(basicBlock.get(), basicBlock->end());
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pBuilder->createUncondBrInst(thebrBlock, {});
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changed = true; // 标记IR被修改
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continue;
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}
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if (thelastBlockOld != nullptr) {
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for (auto &InstInNew : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))->getInstructions()) {
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if (InstInNew->isPhi()) {
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// 使用 delBlk 方法删除 oldBlock 对应的传入值
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dynamic_cast<PhiInst *>(InstInNew.get())->delBlk(thelastBlockOld);
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} else {
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break;
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}
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}
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}
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thelastBlockOld = nullptr;
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while (EmptyBlocks.count(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2)))) {
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thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2));
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thelastinst->get()->replaceOperand(
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2, EmptyBlocks[dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))]);
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elseChanged = true;
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}
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if (elseChanged) {
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basicBlock->removeSuccessor(OldElseBlock);
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OldElseBlock->removePredecessor(basicBlock.get());
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basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2)));
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dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))->addPredecessor(basicBlock.get());
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changed = true; // 标记IR被修改
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}
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// 处理 then 和 else 分支合并的情况
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if (dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)) ==
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dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))) {
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auto thebrBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1));
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SysYIROptUtils::usedelete(thelastinst->get());
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thelastinst = basicBlock->getInstructions().erase(thelastinst);
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pBuilder->setPosition(basicBlock.get(), basicBlock->end());
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pBuilder->createUncondBrInst(thebrBlock, {});
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changed = true; // 标记IR被修改
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continue;
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}
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// 如果有重定向发生
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// 需要更新后继块的前驱关系
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if (thelastBlockOld != nullptr) {
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for (auto &InstInNew : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))->getInstructions()) {
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if (InstInNew->isPhi()) {
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// 使用 delBlk 方法删除 oldBlock 对应的传入值
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dynamic_cast<PhiInst *>(InstInNew.get())->delBlk(thelastBlockOld);
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} else {
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break;
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}
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}
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}
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} else {
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// 如果不是终止指令，但有后继 (例如，末尾没有显式终止指令的块)
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// 这段逻辑可能需要更严谨的CFG检查来确保正确性
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if (basicBlock->getNumSuccessors() == 1) {
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// 这里的逻辑似乎是想为没有terminator的块添加一个，但通常这应该在CFG构建阶段完成。
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// 如果这里仍然执行，确保它符合预期。
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// pBuilder->setPosition(basicBlock.get(), basicBlock->end());
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// pBuilder->createUncondBrInst(basicBlock->getSuccessors()[0], {});
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// auto thelastinst = basicBlock->getInstructions().end();
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// (--thelastinst);
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// auto OldBrBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
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// sysy::BasicBlock *thelastBlockOld = nullptr;
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// while (EmptyBlocks.find(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))) !=
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// EmptyBlocks.end()) {
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// thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
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// thelastinst->get()->replaceOperand(
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// 0, EmptyBlocks[dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))]);
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// }
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// basicBlock->removeSuccessor(OldBrBlock);
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// OldBrBlock->removePredecessor(basicBlock.get());
|
||||
// basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0)));
|
||||
// dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->addPredecessor(basicBlock.get());
|
||||
// changed = true; // 标记IR被修改
|
||||
// if (thelastBlockOld != nullptr) {
|
||||
// int indexphi = 0;
|
||||
// for (auto &pred : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->getPredecessors()) {
|
||||
// if (pred == thelastBlockOld) {
|
||||
// break;
|
||||
// }
|
||||
// indexphi++;
|
||||
// }
|
||||
|
||||
// for (auto &InstInNew : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->getInstructions()) {
|
||||
// if (InstInNew->isPhi()) {
|
||||
// dynamic_cast<PhiInst *>(InstInNew.get())->removeOperand(indexphi + 1);
|
||||
// } else {
|
||||
// break;
|
||||
// }
|
||||
// }
|
||||
// }
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// 真正的删除空块
|
||||
for (auto iter = func->getBasicBlocks().begin(); iter != func->getBasicBlocks().end();) {
|
||||
|
||||
if (EmptyBlocks.count(iter->get())) {
|
||||
// EntryBlock跳过
|
||||
if (iter->get() == func->getEntryBlock()) {
|
||||
++iter;
|
||||
continue;
|
||||
}
|
||||
|
||||
for (auto instIter = iter->get()->getInstructions().begin();
|
||||
instIter != iter->get()->getInstructions().end();) {
|
||||
SysYIROptUtils::usedelete(instIter->get()); // 仅删除 use 关系
|
||||
// 显式地从基本块中删除指令并更新迭代器
|
||||
instIter = iter->get()->getInstructions().erase(instIter);
|
||||
}
|
||||
// 删除不可达基本块的phi指令的操作数
|
||||
for (auto &succ : iter->get()->getSuccessors()) {
|
||||
for (auto &instinsucc : succ->getInstructions()) {
|
||||
if (instinsucc->isPhi()) {
|
||||
// iter->get() 就是当前被删除的空基本块，它作为前驱连接到这里的Phi指令
|
||||
dynamic_cast<PhiInst *>(instinsucc.get())->delBlk(iter->get());
|
||||
} else {
|
||||
// Phi 指令通常在基本块的开头，如果不是 Phi 指令就停止检查
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func->removeBasicBlock((iter++)->get());
|
||||
changed = true;
|
||||
} else {
|
||||
++iter;
|
||||
}
|
||||
}
|
||||
|
||||
return changed;
|
||||
}
|
||||
|
||||
// 如果函数没有返回指令，则添加一个默认返回指令(主要解决void函数没有返回指令的问题)
|
||||
bool SysYCFGOptUtils::SysYAddReturn(Function *func, IRBuilder* pBuilder) {
|
||||
bool changed = false;
|
||||
auto basicBlocks = func->getBasicBlocks();
|
||||
for (auto &block : basicBlocks) {
|
||||
if (block->getNumSuccessors() == 0) {
|
||||
// 如果基本块没有后继块，则添加一个返回指令
|
||||
if (block->getNumInstructions() == 0) {
|
||||
pBuilder->setPosition(block.get(), block->end());
|
||||
pBuilder->createReturnInst();
|
||||
changed = true; // 标记IR被修改
|
||||
} else {
|
||||
auto thelastinst = block->getInstructions().end();
|
||||
--thelastinst;
|
||||
if (thelastinst->get()->getKind() != Instruction::kReturn) {
|
||||
// std::cout << "Warning: Function " << func->getName() << " has no return instruction, adding default return." << std::endl;
|
||||
|
||||
pBuilder->setPosition(block.get(), block->end());
|
||||
// TODO: 如果int float函数缺少返回值是否需要报错
|
||||
if (func->getReturnType()->isInt()) {
|
||||
pBuilder->createReturnInst(ConstantInteger::get(0));
|
||||
} else if (func->getReturnType()->isFloat()) {
|
||||
pBuilder->createReturnInst(ConstantFloating::get(0.0F));
|
||||
} else {
|
||||
pBuilder->createReturnInst();
|
||||
}
|
||||
changed = true; // 标记IR被修改
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return changed;
|
||||
}
|
||||
|
||||
// 条件分支转换为无条件分支
|
||||
// 主要针对已知条件值的分支转换为无条件分支
|
||||
// 例如 if (cond) { ... } else { ... } 中的 cond 已经
|
||||
// 确定为 true 或 false 的情况
|
||||
bool SysYCFGOptUtils::SysYCondBr2Br(Function *func, IRBuilder* pBuilder) {
|
||||
bool changed = false;
|
||||
|
||||
for (auto &basicblock : func->getBasicBlocks()) {
|
||||
if (basicblock->getNumInstructions() == 0)
|
||||
continue;
|
||||
|
||||
auto thelast = basicblock->getInstructions().end();
|
||||
--thelast;
|
||||
|
||||
if (thelast->get()->isConditional()){
|
||||
ConstantValue *constOperand = dynamic_cast<ConstantValue *>(thelast->get()->getOperand(0));
|
||||
std::string opname;
|
||||
int constint = 0;
|
||||
float constfloat = 0.0F;
|
||||
bool constint_Use = false;
|
||||
bool constfloat_Use = false;
|
||||
if (constOperand != nullptr) {
|
||||
if (constOperand->isFloat()) {
|
||||
constfloat = constOperand->getFloat();
|
||||
constfloat_Use = true;
|
||||
} else {
|
||||
constint = constOperand->getInt();
|
||||
constint_Use = true;
|
||||
}
|
||||
}
|
||||
// 如果可以计算
|
||||
if (constfloat_Use || constint_Use) {
|
||||
changed = true;
|
||||
|
||||
auto thenBlock = dynamic_cast<BasicBlock *>(thelast->get()->getOperand(1));
|
||||
auto elseBlock = dynamic_cast<BasicBlock *>(thelast->get()->getOperand(2));
|
||||
SysYIROptUtils::usedelete(thelast->get());
|
||||
thelast = basicblock->getInstructions().erase(thelast);
|
||||
if ((constfloat_Use && constfloat == 1.0F) || (constint_Use && constint == 1)) {
|
||||
// cond为true或非0
|
||||
pBuilder->setPosition(basicblock.get(), basicblock->end());
|
||||
pBuilder->createUncondBrInst(thenBlock, {});
|
||||
|
||||
// 更新CFG关系
|
||||
basicblock->removeSuccessor(elseBlock);
|
||||
elseBlock->removePredecessor(basicblock.get());
|
||||
|
||||
// 删除elseBlock的phi指令中对应的basicblock.get()的传入值
|
||||
for (auto &phiinst : elseBlock->getInstructions()) {
|
||||
if (phiinst->getKind() != Instruction::kPhi) {
|
||||
break;
|
||||
}
|
||||
// 使用 delBlk 方法删除 basicblock.get() 对应的传入值
|
||||
dynamic_cast<PhiInst *>(phiinst.get())->delBlk(basicblock.get());
|
||||
}
|
||||
|
||||
} else { // cond为false或0
|
||||
|
||||
pBuilder->setPosition(basicblock.get(), basicblock->end());
|
||||
pBuilder->createUncondBrInst(elseBlock, {});
|
||||
|
||||
// 更新CFG关系
|
||||
basicblock->removeSuccessor(thenBlock);
|
||||
thenBlock->removePredecessor(basicblock.get());
|
||||
|
||||
// 删除thenBlock的phi指令中对应的basicblock.get()的传入值
|
||||
for (auto &phiinst : thenBlock->getInstructions()) {
|
||||
if (phiinst->getKind() != Instruction::kPhi) {
|
||||
break;
|
||||
}
|
||||
// 使用 delBlk 方法删除 basicblock.get() 对应的传入值
|
||||
dynamic_cast<PhiInst *>(phiinst.get())->delBlk(basicblock.get());
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return changed;
|
||||
}
|
||||
|
||||
// ======================================================================
|
||||
// 独立的CFG优化遍的实现
|
||||
// ======================================================================
|
||||
|
||||
bool SysYDelInstAfterBrPass::runOnFunction(Function *F, AnalysisManager& AM) {
|
||||
return SysYCFGOptUtils::SysYDelInstAfterBr(F);
|
||||
}
|
||||
|
||||
bool SysYDelEmptyBlockPass::runOnFunction(Function *F, AnalysisManager& AM) {
|
||||
return SysYCFGOptUtils::SysYDelEmptyBlock(F, pBuilder);
|
||||
}
|
||||
|
||||
bool SysYDelNoPreBLockPass::runOnFunction(Function *F, AnalysisManager& AM) {
|
||||
return SysYCFGOptUtils::SysYDelNoPreBLock(F);
|
||||
}
|
||||
|
||||
bool SysYBlockMergePass::runOnFunction(Function *F, AnalysisManager& AM) {
|
||||
return SysYCFGOptUtils::SysYBlockMerge(F);
|
||||
}
|
||||
|
||||
bool SysYAddReturnPass::runOnFunction(Function *F, AnalysisManager& AM) {
|
||||
return SysYCFGOptUtils::SysYAddReturn(F, pBuilder);
|
||||
}
|
||||
|
||||
bool SysYCondBr2BrPass::runOnFunction(Function *F, AnalysisManager& AM) {
|
||||
return SysYCFGOptUtils::SysYCondBr2Br(F, pBuilder);
|
||||
}
|
||||
|
||||
} // namespace sysy
|
||||
Reference in New Issue
Block a user