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[midend]更新遍静态ID定义方法，

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注册遍模板函数重构（针对遍的不同构造方法），
修复phi指令更新引起的旧代码错误，
将CFG优化适配到现有终端框架中，
独立CFG优化方法使得其他优化遍能独立调用，
usedelete方法回调取消删除功能。
IRGenerator代码风格修改。
This commit is contained in:
rain2133
2025-07-23 17:19:11 +08:00
parent 3df3d7a097
commit 87d38be255
12 changed files with 509 additions and 298 deletions
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389
src/SysYIRCFGOpt.cpp
View File

@@ -6,14 +6,25 @@
#include <memory>
#include <string>
#include <iostream>
#include "IR.h"
#include "IRBuilder.h"
#include <queue> // 引入队列，SysYDelNoPreBLock需要
namespace sysy {
// 定义静态ID
void *SysYDelInstAfterBrPass::ID = (void *)&SysYDelInstAfterBrPass::ID;
void *SysYDelEmptyBlockPass::ID = (void *)&SysYDelEmptyBlockPass::ID;
void *SysYDelNoPreBLockPass::ID = (void *)&SysYDelNoPreBLockPass::ID;
void *SysYBlockMergePass::ID = (void *)&SysYBlockMergePass::ID;
void *SysYAddReturnPass::ID = (void *)&SysYAddReturnPass::ID;
void *SysYCondBr2BrPass::ID = (void *)&SysYCondBr2BrPass::ID;
// ======================================================================
// SysYCFGOptUtils: 辅助工具类，包含实际的CFG优化逻辑
// ======================================================================
// 删除br后的无用指令
bool SysYCFGOpt::SysYDelInstAfterBr(Function *func) {
bool SysYCFGOptUtils::SysYDelInstAfterBr(Function *func) {
bool changed = false;
auto basicBlocks = func->getBasicBlocks();
@@ -22,11 +33,10 @@ bool SysYCFGOpt::SysYDelInstAfterBr(Function *func) {
auto &instructions = basicBlock->getInstructions();
auto Branchiter = instructions.end();
for (auto iter = instructions.begin(); iter != instructions.end(); ++iter) {
if (Branch)
SysYIROptUtils::usedelete(iter->get());
else if ((*iter)->isTerminator()){
if ((*iter)->isTerminator()){
Branch = true;
Branchiter = iter;
break;
}
}
if (Branchiter != instructions.end()) ++Branchiter;
@@ -61,8 +71,8 @@ bool SysYCFGOpt::SysYDelInstAfterBr(Function *func) {
return changed;
}
// 合并空基本块
bool SysYCFGOpt::SysYBlockMerge(Function *func) {
// 合并基本块
bool SysYCFGOptUtils::SysYBlockMerge(Function *func) {
bool changed = false;
for (auto blockiter = func->getBasicBlocks().begin();
@@ -82,12 +92,12 @@ bool SysYCFGOpt::SysYBlockMerge(Function *func) {
(--thelastinstinst);
if (thelastinstinst->get()->isUnconditional()) {
SysYIROptUtils::usedelete(thelastinstinst->get());
block->getInstructions().erase(thelastinstinst);
thelastinstinst = block->getInstructions().erase(thelastinstinst);
} else if (thelastinstinst->get()->isConditional()) {
// 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
if (thelastinstinst->get()->getOperand(1)->getName() == thelastinstinst->get()->getOperand(1)->getName()) {
SysYIROptUtils::usedelete(thelastinstinst->get());
block->getInstructions().erase(thelastinstinst);
thelastinstinst = block->getInstructions().erase(thelastinstinst);
}
}
}
@@ -132,7 +142,7 @@ bool SysYCFGOpt::SysYBlockMerge(Function *func) {
}
// 删除无前驱块，兼容SSA后的处理
bool SysYCFGOpt::SysYDelNoPreBLock(Function *func) {
bool SysYCFGOptUtils::SysYDelNoPreBLock(Function *func) {
bool changed = false;
@@ -156,29 +166,26 @@ bool SysYCFGOpt::SysYDelNoPreBLock(Function *func) {
}
// 删除不可达基本块指令
for (auto blockIter = func->getBasicBlocks().begin(); blockIter != func->getBasicBlocks().end();blockIter++) {
if (!blockIter->get()->getreachable())
for (auto &iterInst : blockIter->get()->getInstructions())
SysYIROptUtils::usedelete(iterInst.get());
for (auto blockIter = func->getBasicBlocks().begin(); blockIter != func->getBasicBlocks().end(); blockIter++) {
if (!blockIter->get()->getreachable()) {
for (auto instIter = blockIter->get()->getInstructions().begin();
instIter != blockIter->get()->getInstructions().end();) {
SysYIROptUtils::usedelete(instIter->get());
instIter = blockIter->get()->getInstructions().erase(instIter);
}
}
}
for (auto blockIter = func->getBasicBlocks().begin(); blockIter != func->getBasicBlocks().end();) {
if (!blockIter->get()->getreachable()) {
for (auto succblock : blockIter->get()->getSuccessors()) {
int indexphi = 1;
for (auto pred : succblock->getPredecessors()) {
if (pred == blockIter->get()) {
break;
}
indexphi++;
}
for (auto &phiinst : succblock->getInstructions()) {
if (phiinst->getKind() != Instruction::kPhi) {
break;
}
phiinst->removeOperand(indexphi);
if (phiinst->getKind() != Instruction::kPhi) {
break;
}
// 使用 delBlk 方法正确地删除对应于被删除基本块的传入值
dynamic_cast<PhiInst *>(phiinst.get())->delBlk(blockIter->get());
}
}
// 删除不可达基本块，注意迭代器不可达问题
@@ -193,7 +200,7 @@ bool SysYCFGOpt::SysYDelNoPreBLock(Function *func) {
}
// 删除空块
bool SysYCFGOpt::SysYDelEmptyBlock(Function *func, IRBuilder* pBuilder) {
bool SysYCFGOptUtils::SysYDelEmptyBlock(Function *func, IRBuilder* pBuilder) {
bool changed = false;
// 收集不可达基本块
@@ -218,24 +225,29 @@ bool SysYCFGOpt::SysYDelEmptyBlock(Function *func, IRBuilder* pBuilder) {
break;
}
}
if(onlyPhi)
if(onlyPhi && basicBlock->getNumSuccessors() == 1) // 确保有后继且只有一个
EmptyBlocks[basicBlock.get()] = basicBlock->getSuccessors().front();
}
}
// 更新基本块信息，增加必要指令
for (auto &basicBlock : basicBlocks) {
// 把空块转换成只有跳转指令的不可达块
// 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)
// 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。
// 但是，它主要目的是重定向跳转。
if (distance(basicBlock->begin(), basicBlock->end()) == 0) {
if (basicBlock->getNumSuccessors() == 0) {
continue;
}
if (basicBlock->getNumSuccessors() > 1) {
assert("");
// 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
assert(false && "Empty block with multiple successors found during SysYDelEmptyBlock");
}
pBuilder->setPosition(basicBlock.get(), basicBlock->end());
pBuilder->createUncondBrInst(basicBlock->getSuccessors()[0], {});
// 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。
// 如果这个块最终被删除了，那么其前驱也需要重定向。
// 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。
// 所以下面的逻辑才是核心。
// pBuilder->setPosition(basicBlock.get(), basicBlock->end());
// pBuilder->createUncondBrInst(basicBlock->getSuccessors()[0], {});
continue;
}
@@ -247,50 +259,55 @@ bool SysYCFGOpt::SysYDelEmptyBlock(Function *func, IRBuilder* pBuilder) {
BasicBlock* OldBrBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
BasicBlock *thelastBlockOld = nullptr;
// 如果空块链表为多个块
while (EmptyBlocks.find(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))) !=
EmptyBlocks.end()) {
while (EmptyBlocks.count(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0)))) {
thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
thelastinst->get()->replaceOperand(0, EmptyBlocks[thelastBlockOld]);
}
basicBlock->removeSuccessor(OldBrBlock);
OldBrBlock->removePredecessor(basicBlock.get());
basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0)));
dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->addPredecessor(basicBlock.get());
// 如果有重定向发生
if (thelastBlockOld != nullptr) {
basicBlock->removeSuccessor(OldBrBlock);
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++;
}
// 更新phi指令的操作数
// 移除thelastBlockOld对应的phi操作数
for (auto &InstInNew : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->getInstructions()) {
if (InstInNew->isPhi()) {
dynamic_cast<PhiInst *>(InstInNew.get())->removeOperand(indexphi + 1);
} else {
break;
}
if (InstInNew->isPhi()) {
// 使用 delBlk 方法删除 oldBlock 对应的传入值
dynamic_cast<PhiInst *>(InstInNew.get())->delBlk(thelastBlockOld);
} else {
break;
}
}
}
} else if (thelastinst->get()->getKind() == Instruction::kCondBr) {
auto OldThenBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1));
auto OldElseBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2));
bool thenChanged = false;
bool elseChanged = false;
BasicBlock *thelastBlockOld = nullptr;
while (EmptyBlocks.find(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))) !=
EmptyBlocks.end()) {
while (EmptyBlocks.count(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)))) {
thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1));
thelastinst->get()->replaceOperand(
1, EmptyBlocks[dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))]);
thenChanged = true;
}
basicBlock->removeSuccessor(OldThenBlock);
OldThenBlock->removePredecessor(basicBlock.get());
if (thenChanged) {
basicBlock->removeSuccessor(OldThenBlock);
OldThenBlock->removePredecessor(basicBlock.get());
basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)));
dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))->addPredecessor(basicBlock.get());
changed = true; // 标记IR被修改
}
// 处理 then 和 else 分支合并的情况
if (dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)) ==
dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))) {
@@ -299,39 +316,37 @@ bool SysYCFGOpt::SysYDelEmptyBlock(Function *func, IRBuilder* pBuilder) {
thelastinst = basicBlock->getInstructions().erase(thelastinst);
pBuilder->setPosition(basicBlock.get(), basicBlock->end());
pBuilder->createUncondBrInst(thebrBlock, {});
changed = true; // 标记IR被修改
continue;
}
basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)));
dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))->addPredecessor(basicBlock.get());
// auto indexInNew = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->getPredecessors().
if (thelastBlockOld != nullptr) {
int indexphi = 0;
for (auto &pred : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))->getPredecessors()) {
if (pred == thelastBlockOld) {
break;
}
indexphi++;
}
for (auto &InstInNew : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1))->getInstructions()) {
if (InstInNew->isPhi()) {
dynamic_cast<PhiInst *>(InstInNew.get())->removeOperand(indexphi + 1);
// 使用 delBlk 方法删除 oldBlock 对应的传入值
dynamic_cast<PhiInst *>(InstInNew.get())->delBlk(thelastBlockOld);
} else {
break;
}
}
}
}
thelastBlockOld = nullptr;
while (EmptyBlocks.find(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))) !=
EmptyBlocks.end()) {
while (EmptyBlocks.count(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2)))) {
thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2));
thelastinst->get()->replaceOperand(
2, EmptyBlocks[dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))]);
elseChanged = true;
}
basicBlock->removeSuccessor(OldElseBlock);
OldElseBlock->removePredecessor(basicBlock.get());
if (elseChanged) {
basicBlock->removeSuccessor(OldElseBlock);
OldElseBlock->removePredecessor(basicBlock.get());
basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2)));
dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))->addPredecessor(basicBlock.get());
changed = true; // 标记IR被修改
}
// 处理 then 和 else 分支合并的情况
if (dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(1)) ==
dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))) {
@@ -340,93 +355,94 @@ bool SysYCFGOpt::SysYDelEmptyBlock(Function *func, IRBuilder* pBuilder) {
thelastinst = basicBlock->getInstructions().erase(thelastinst);
pBuilder->setPosition(basicBlock.get(), basicBlock->end());
pBuilder->createUncondBrInst(thebrBlock, {});
changed = true; // 标记IR被修改
continue;
}
basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2)));
dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))->addPredecessor(basicBlock.get());
// 如果有重定向发生
// 需要更新后继块的前驱关系
if (thelastBlockOld != nullptr) {
int indexphi = 0;
for (auto &pred : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))->getPredecessors()) {
if (pred == thelastBlockOld) {
break;
}
indexphi++;
}
for (auto &InstInNew : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(2))->getInstructions()) {
if (InstInNew->isPhi()) {
dynamic_cast<PhiInst *>(InstInNew.get())->removeOperand(indexphi + 1);
// 使用 delBlk 方法删除 oldBlock 对应的传入值
dynamic_cast<PhiInst *>(InstInNew.get())->delBlk(thelastBlockOld);
} else {
break;
}
}
}
}
} else {
// 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)
// 这段逻辑可能需要更严谨的CFG检查来确保正确性
if (basicBlock->getNumSuccessors() == 1) {
pBuilder->setPosition(basicBlock.get(), basicBlock->end());
pBuilder->createUncondBrInst(basicBlock->getSuccessors()[0], {});
auto thelastinst = basicBlock->getInstructions().end();
(--thelastinst);
auto OldBrBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
sysy::BasicBlock *thelastBlockOld = nullptr;
while (EmptyBlocks.find(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))) !=
EmptyBlocks.end()) {
thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
// 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。
// 如果这里仍然执行，确保它符合预期。
// pBuilder->setPosition(basicBlock.get(), basicBlock->end());
// pBuilder->createUncondBrInst(basicBlock->getSuccessors()[0], {});
// auto thelastinst = basicBlock->getInstructions().end();
// (--thelastinst);
// auto OldBrBlock = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
// sysy::BasicBlock *thelastBlockOld = nullptr;
// while (EmptyBlocks.find(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))) !=
// EmptyBlocks.end()) {
// thelastBlockOld = dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0));
thelastinst->get()->replaceOperand(
0, EmptyBlocks[dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))]);
}
// thelastinst->get()->replaceOperand(
// 0, EmptyBlocks[dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))]);
// }
basicBlock->removeSuccessor(OldBrBlock);
OldBrBlock->removePredecessor(basicBlock.get());
basicBlock->addSuccessor(dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0)));
dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->addPredecessor(basicBlock.get());
if (thelastBlockOld != nullptr) {
int indexphi = 0;
for (auto &pred : dynamic_cast<BasicBlock *>(thelastinst->get()->getOperand(0))->getPredecessors()) {
if (pred == thelastBlockOld) {
break;
}
indexphi++;
}
// basicBlock->removeSuccessor(OldBrBlock);
// 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;
}
}
}
// 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.find(iter->get()) != EmptyBlocks.end()) {
if (EmptyBlocks.count(iter->get())) {
// EntryBlock跳过
if (iter->get() == func->getEntryBlock()) {
++iter;
continue;
}
for (auto &iterInst : iter->get()->getInstructions())
SysYIROptUtils::usedelete(iterInst.get());
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()) {
int index = 0;
for (auto &pred : succ->getPredecessors()) {
if (pred == iter->get()) {
break;
}
index++;
}
for (auto &instinsucc : succ->getInstructions()) {
if (instinsucc->isPhi()) {
dynamic_cast<PhiInst *>(instinsucc.get())->removeOperand(index);
// 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;
}
}
@@ -440,34 +456,35 @@ bool SysYCFGOpt::SysYDelEmptyBlock(Function *func, IRBuilder* pBuilder) {
}
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 SysYCFGOpt::SysYAddReturn(Function *func, IRBuilder* pBuilder) {
bool SysYCFGOptUtils::SysYAddReturn(Function *func, IRBuilder* pBuilder) {
bool changed = false;
auto basicBlocks = func->getBasicBlocks();
for (auto &block : basicBlocks) {
if (block->getNumSuccessors() == 0) {
changed = true;
// 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();
}
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;
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();
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
}
}
}
@@ -480,7 +497,7 @@ bool SysYCFGOpt::SysYAddReturn(Function *func, IRBuilder* pBuilder) {
// 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 SysYCFGOpt::SysYCondBr2Br(Function *func, IRBuilder* pBuilder) {
bool SysYCFGOptUtils::SysYCondBr2Br(Function *func, IRBuilder* pBuilder) {
bool changed = false;
for (auto &basicblock : func->getBasicBlocks()) {
@@ -515,45 +532,41 @@ bool SysYCFGOpt::SysYCondBr2Br(Function *func, IRBuilder* pBuilder) {
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, {});
int phiindex = 0;
for (auto pred : elseBlock->getPredecessors()) {
phiindex++;
if (pred == basicblock.get()) {
break;
}
}
// 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;
}
phiinst->removeOperand(phiindex);
// 使用 delBlk 方法删除 basicblock.get() 对应的传入值
dynamic_cast<PhiInst *>(phiinst.get())->delBlk(basicblock.get());
}
basicblock->removeSuccessor(elseBlock);
elseBlock->removePredecessor(basicblock.get());
} else {
} else { // cond为false或0
pBuilder->setPosition(basicblock.get(), basicblock->end());
pBuilder->createUncondBrInst(elseBlock, {});
int phiindex = 0;
for (auto pred : thenBlock->getPredecessors()) {
phiindex++;
if (pred == basicblock.get()) {
break;
}
}
// 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;
}
phiinst->removeOperand(phiindex);
// 使用 delBlk 方法删除 basicblock.get() 对应的传入值
dynamic_cast<PhiInst *>(phiinst.get())->delBlk(basicblock.get());
}
basicblock->removeSuccessor(thenBlock);
thenBlock->removePredecessor(basicblock.get());
}
}
}
@@ -562,4 +575,32 @@ bool SysYCFGOpt::SysYCondBr2Br(Function *func, IRBuilder* pBuilder) {
return changed;
}
} // namespace sysy
// ======================================================================
// 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