[midend-tco]修复命名重复问题

src/backend/RISCv64/Optimize/Peephole.cpp

@@ -634,6 +634,22 @@ void PeepholeOptimizer::runOnMachineFunction(MachineFunction *mfunc) {
           }
         }
       }
+      // 8. 消除无用移动指令: mv a, a -> (删除)
+      else if (mi1->getOpcode() == RVOpcodes::MV &&
+               mi1->getOperands().size() == 2) {
+        if (mi1->getOperands()[0]->getKind() == MachineOperand::KIND_REG &&
+            mi1->getOperands()[1]->getKind() == MachineOperand::KIND_REG) {
+          auto *dst = static_cast<RegOperand *>(mi1->getOperands()[0].get());
+          auto *src = static_cast<RegOperand *>(mi1->getOperands()[1].get());
+          
+          // 检查源和目标寄存器是否相同
+          if (areRegsEqual(dst, src)) {
+            // 删除这条无用指令
+            instrs.erase(instrs.begin() + i);
+            changed = true;
+          }
+        }
+      }
 
       // 根据是否发生变化调整遍历索引
       if (!changed) {

src/include/midend/Pass/Optimize/GlobalStrengthReduction.h

@@ -0,0 +1,107 @@
+#pragma once
+
+#include "Pass.h"
+#include "IR.h"
+#include "SideEffectAnalysis.h"
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
+#include <cstdint>
+
+namespace sysy {
+
+// 魔数乘法结构，用于除法优化
+struct MagicNumber {
+    uint32_t multiplier;
+    int shift;
+    bool needAdd;
+    
+    MagicNumber(uint32_t m, int s, bool add = false) 
+        : multiplier(m), shift(s), needAdd(add) {}
+};
+
+// 全局强度削弱优化遍的核心逻辑封装类
+class GlobalStrengthReductionContext {
+public:
+    // 构造函数，接受IRBuilder参数
+    explicit GlobalStrengthReductionContext(IRBuilder* builder) : builder(builder) {}
+    
+    // 运行优化的主要方法
+    void run(Function* func, AnalysisManager* AM, bool& changed);
+
+private:
+    IRBuilder* builder;  // IR构建器
+    
+    // 分析结果
+    SideEffectAnalysisResult* sideEffectAnalysis = nullptr;
+    
+    // 优化计数
+    int algebraicOptCount = 0;
+    int strengthReductionCount = 0;
+    int divisionOptCount = 0;
+    
+    // 主要优化方法
+    bool processBasicBlock(BasicBlock* bb);
+    bool processInstruction(Instruction* inst);
+    
+    // 代数优化方法
+    bool tryAlgebraicOptimization(Instruction* inst);
+    bool optimizeAddition(BinaryInst* inst);
+    bool optimizeSubtraction(BinaryInst* inst);
+    bool optimizeMultiplication(BinaryInst* inst);
+    bool optimizeDivision(BinaryInst* inst);
+    bool optimizeComparison(BinaryInst* inst);
+    bool optimizeLogical(BinaryInst* inst);
+    
+    // 强度削弱方法
+    bool tryStrengthReduction(Instruction* inst);
+    bool reduceMultiplication(BinaryInst* inst);
+    bool reduceDivision(BinaryInst* inst);
+    bool reducePower(CallInst* inst);
+    
+    // 复杂乘法强度削弱方法
+    bool tryComplexMultiplication(BinaryInst* inst, Value* variable, int constant);
+    bool findOptimalShiftDecomposition(int constant, std::vector<int>& shifts);
+    Value* createShiftDecomposition(BinaryInst* inst, Value* variable, const std::vector<int>& shifts);
+    
+    // 魔数乘法相关方法
+    MagicNumber computeMagicNumber(uint32_t divisor);
+    std::pair<int, int> computeMulhMagicNumbers(int divisor);
+    Value* createMagicDivision(BinaryInst* divInst, uint32_t divisor, const MagicNumber& magic);
+    Value* createMagicDivisionLibdivide(BinaryInst* divInst, int divisor);
+    bool isPowerOfTwo(uint32_t n);
+    int log2OfPowerOfTwo(uint32_t n);
+    
+    // 辅助方法
+    bool isConstantInt(Value* val, int& constVal);
+    bool isConstantInt(Value* val, uint32_t& constVal);
+    ConstantInteger* getConstantInt(int val);
+    bool hasOnlyLocalUses(Instruction* inst);
+    void replaceWithOptimized(Instruction* original, Value* replacement);
+};
+
+// 全局强度削弱优化遍类
+class GlobalStrengthReduction : public OptimizationPass {
+private:
+    IRBuilder* builder;  // IR构建器，用于创建新指令
+
+public:
+    // 静态成员，作为该遍的唯一ID
+    static void* ID;
+    
+    // 构造函数，接受IRBuilder参数
+    explicit GlobalStrengthReduction(IRBuilder* builder) 
+        : OptimizationPass("GlobalStrengthReduction", Granularity::Function), builder(builder) {}
+    
+    // 在函数上运行优化
+    bool runOnFunction(Function* func, AnalysisManager& AM) override;
+    
+    // 返回该遍的唯一ID
+    void* getPassID() const override { return ID; }
+    
+    // 声明分析依赖
+    void getAnalysisUsage(std::set<void*>& analysisDependencies, 
+                         std::set<void*>& analysisInvalidations) const override;
+};
+
+} // namespace sysy

src/include/midend/Pass/Optimize/LoopStrengthReduction.h

@@ -127,13 +127,6 @@ private:
    */
   bool analyzeInductionVariableRange(const InductionVarInfo* ivInfo, Loop* loop) const;
   
-  /**
-   * 计算用于除法优化的魔数和移位量
-   * @param divisor 除数
-   * @return {魔数, 移位量}
-   */
-  std::pair<int, int> computeMulhMagicNumbers(int divisor) const;
-  
   /**
    * 生成除法替换代码
    * @param candidate 优化候选项

src/include/midend/Pass/Optimize/SysYIROptUtils.h

@@ -107,6 +107,190 @@ public:
     // 所以当AllocaInst的basetype是PointerType时（一维数组）或者是指向ArrayType的PointerType（多位数组）时，返回true
     return aval && (baseType->isPointer() || baseType->as<PointerType>()->getBaseType()->isArray());
   }
+
+  
+  //该实现参考了libdivide的算法
+  static std::pair<int, int> computeMulhMagicNumbers(int divisor) {
+    
+    if (DEBUG) {
+      std::cout << "\n[SR] ===== Computing magic numbers for divisor " << divisor << " (libdivide algorithm) =====" << std::endl;
+    }
+    
+    if (divisor == 0) {
+      if (DEBUG) std::cout << "[SR] Error: divisor must be != 0" << std::endl;
+      return {-1, -1};
+    }
+
+    // libdivide 常数
+    const uint8_t LIBDIVIDE_ADD_MARKER = 0x40;
+    const uint8_t LIBDIVIDE_NEGATIVE_DIVISOR = 0x80;
+    
+    // 辅助函数：计算前导零个数
+    auto count_leading_zeros32 = [](uint32_t val) -> uint32_t {
+      if (val == 0) return 32;
+      return __builtin_clz(val);
+    };
+    
+    // 辅助函数：64位除法返回32位商和余数
+    auto div_64_32 = [](uint32_t high, uint32_t low, uint32_t divisor, uint32_t* rem) -> uint32_t {
+      uint64_t dividend = ((uint64_t)high << 32) | low;
+      uint32_t quotient = dividend / divisor;
+      *rem = dividend % divisor;
+      return quotient;
+    };
+
+    if (DEBUG) {
+      std::cout << "[SR] Input divisor: " << divisor << std::endl;
+    }
+
+    // libdivide_internal_s32_gen 算法实现
+    int32_t d = divisor;
+    uint32_t ud = (uint32_t)d;
+    uint32_t absD = (d < 0) ? -ud : ud;
+    
+    if (DEBUG) {
+      std::cout << "[SR] absD = " << absD << std::endl;
+    }
+    
+    uint32_t floor_log_2_d = 31 - count_leading_zeros32(absD);
+    
+    if (DEBUG) {
+      std::cout << "[SR] floor_log_2_d = " << floor_log_2_d << std::endl;
+    }
+    
+    // 检查 absD 是否为2的幂
+    if ((absD & (absD - 1)) == 0) {
+      if (DEBUG) {
+        std::cout << "[SR] " << absD << " 是2的幂，使用移位方法" << std::endl;
+      }
+      
+      // 对于2的幂，我们只使用移位，不需要魔数
+      int shift = floor_log_2_d;
+      if (d < 0) shift |= 0x80; // 标记负数
+      
+      if (DEBUG) {
+        std::cout << "[SR] Power of 2 result: magic=0, shift=" << shift << std::endl;
+        std::cout << "[SR] ===== End magic computation =====" << std::endl;
+      }
+      
+      // 对于我们的目的，我们将在IR生成中以不同方式处理2的幂
+      // 返回特殊标记
+      return {0, shift};
+    }
+    
+    if (DEBUG) {
+      std::cout << "[SR] " << absD << " is not a power of 2, computing magic number" << std::endl;
+    }
+    
+    // 非2的幂除数的魔数计算
+    uint8_t more;
+    uint32_t rem, proposed_m;
+    
+    // 计算 proposed_m = floor(2^(floor_log_2_d + 31) / absD)
+    proposed_m = div_64_32((uint32_t)1 << (floor_log_2_d - 1), 0, absD, &rem);
+    const uint32_t e = absD - rem;
+    
+    if (DEBUG) {
+      std::cout << "[SR] proposed_m = " << proposed_m << ", rem = " << rem << ", e = " << e << std::endl;
+    }
+    
+    // 确定是否需要"加法"版本
+    const bool branchfree = false; // 使用分支版本
+    
+    if (!branchfree && e < ((uint32_t)1 << floor_log_2_d)) {
+      // 这个幂次有效
+      more = (uint8_t)(floor_log_2_d - 1);
+      if (DEBUG) {
+        std::cout << "[SR] Using basic algorithm, shift = " << (int)more << std::endl;
+      }
+    } else {
+      // 我们需要上升一个等级
+      proposed_m += proposed_m;
+      const uint32_t twice_rem = rem + rem;
+      if (twice_rem >= absD || twice_rem < rem) {
+        proposed_m += 1;
+      }
+      more = (uint8_t)(floor_log_2_d | LIBDIVIDE_ADD_MARKER);
+      if (DEBUG) {
+        std::cout << "[SR] Using add algorithm, proposed_m = " << proposed_m << ", more = " << (int)more << std::endl;
+      }
+    }
+    
+    proposed_m += 1;
+    int32_t magic = (int32_t)proposed_m;
+    
+    // 处理负除数
+    if (d < 0) {
+      more |= LIBDIVIDE_NEGATIVE_DIVISOR;
+      if (!branchfree) {
+        magic = -magic;
+      }
+      if (DEBUG) {
+        std::cout << "[SR] Negative divisor, magic = " << magic << ", more = " << (int)more << std::endl;
+      }
+    }
+    
+    // 为我们的IR生成提取移位量和标志  
+    int shift = more & 0x3F; // 移除标志，保留移位量（位0-5）
+    bool need_add = (more & LIBDIVIDE_ADD_MARKER) != 0;
+    bool is_negative = (more & LIBDIVIDE_NEGATIVE_DIVISOR) != 0;
+    
+    if (DEBUG) {
+      std::cout << "[SR] Final result: magic = " << magic << ", more = " << (int)more 
+                << " (0x" << std::hex << (int)more << std::dec << ")" << std::endl;
+      std::cout << "[SR] Shift = " << shift << ", need_add = " << need_add 
+                << ", is_negative = " << is_negative << std::endl;
+      
+      // Test the magic number using the correct libdivide algorithm
+      std::cout << "[SR] Testing magic number (libdivide algorithm):" << std::endl;
+      int test_values[] = {1, 7, 37, 100, 999, -1, -7, -37, -100};
+      
+      for (int test_val : test_values) {
+        int64_t quotient;
+        
+        // 实现正确的libdivide算法
+        int64_t product = (int64_t)test_val * magic;
+        int64_t high_bits = product >> 32;
+        
+        if (need_add) {
+          // ADD_MARKER情况：移位前加上被除数
+          // 这是libdivide的关键洞察！
+          high_bits += test_val;
+          quotient = high_bits >> shift;
+        } else {
+          // 正常情况：只是移位
+          quotient = high_bits >> shift;
+        }
+        
+        // 符号修正：这是libdivide有符号除法的关键部分！
+        // 如果被除数为负，商需要加1来匹配C语言的截断除法语义
+        if (test_val < 0) {
+          quotient += 1;
+        }
+        
+        int expected = test_val / divisor;
+        
+        bool correct = (quotient == expected);
+        std::cout << "[SR]   " << test_val << " / " << divisor << " = " << quotient 
+                  << " (expected " << expected << ") " << (correct ? "✓" : "✗") << std::endl;
+      }
+      
+      std::cout << "[SR] ===== End magic computation =====" << std::endl;
+    }
+    
+    // 返回魔数、移位量，并在移位中编码ADD_MARKER标志
+    // 我们将使用移位的第6位表示ADD_MARKER，第7位表示负数（如果需要）
+    int encoded_shift = shift;
+    if (need_add) {
+      encoded_shift |= 0x40; // 设置第6位表示ADD_MARKER
+      if (DEBUG) {
+        std::cout << "[SR] Encoding ADD_MARKER in shift: " << encoded_shift << std::endl;
+      }
+    }
+    
+    return {magic, encoded_shift};
+  }
+
 };
 
 }// namespace sysy

src/include/midend/Pass/Optimize/TailCallOpt.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#include "Pass.h"
+#include "Dom.h"
+#include "Loop.h"
+
+namespace sysy {
+
+/**
+ * @class TailCallOpt
+ * @brief 优化尾调用的中端优化通道。
+ *
+ * 该类实现了一个针对函数级别的尾调用优化的优化通道（OptimizationPass）。
+ * 通过分析和转换 IR（中间表示），将可优化的尾调用转换为更高效的形式，
+ * 以减少函数调用的开销，提升程序性能。
+ *
+ * @note 需要传入 IRBuilder 指针用于 IR 构建和修改。
+ *
+ * @method runOnFunction
+ * 对指定函数进行尾调用优化。
+ *
+ * @method getPassID
+ * 获取当前优化通道的唯一标识符。
+ *
+ * @method getAnalysisUsage
+ * 指定该优化通道所依赖和失效的分析集合。
+ */
+class TailCallOpt : public OptimizationPass {
+private:
+  IRBuilder* builder;
+public:
+  TailCallOpt(IRBuilder* builder) : OptimizationPass("TailCallOpt", Granularity::Function), builder(builder) {}
+  static void *ID;
+  bool runOnFunction(Function *F, AnalysisManager &AM) override;
+  void *getPassID() const override { return &ID; }
+  void getAnalysisUsage(std::set<void *> &analysisDependencies, std::set<void *> &analysisInvalidations) const override;
+};
+
+} // namespace sysy

src/midend/CMakeLists.txt

@@ -22,8 +22,10 @@ add_library(midend_lib STATIC
     Pass/Optimize/LICM.cpp
     Pass/Optimize/LoopStrengthReduction.cpp
     Pass/Optimize/InductionVariableElimination.cpp
+    Pass/Optimize/GlobalStrengthReduction.cpp
     Pass/Optimize/BuildCFG.cpp
     Pass/Optimize/LargeArrayToGlobal.cpp
+    Pass/Optimize/TailCallOpt.cpp
 )
 
 # 包含中端模块所需的头文件路径

src/midend/Pass/Optimize/GlobalStrengthReduction.cpp

@@ -0,0 +1,897 @@
+#include "GlobalStrengthReduction.h"
+#include "SysYIROptUtils.h"
+#include "IRBuilder.h"
+#include <algorithm>
+#include <cassert>
+#include <iostream>
+#include <cmath>
+
+extern int DEBUG;
+
+namespace sysy {
+
+// 全局强度削弱优化遍的静态 ID
+void *GlobalStrengthReduction::ID = (void *)&GlobalStrengthReduction::ID;
+
+// ======================================================================
+// GlobalStrengthReduction 类的实现
+// ======================================================================
+
+bool GlobalStrengthReduction::runOnFunction(Function *func, AnalysisManager &AM) {
+  if (func->getBasicBlocks().empty()) {
+    return false;
+  }
+
+  if (DEBUG) {
+    std::cout << "\n=== Running GlobalStrengthReduction on function: " << func->getName() << " ===" << std::endl;
+  }
+
+  bool changed = false;
+  GlobalStrengthReductionContext context(builder);
+  context.run(func, &AM, changed);
+
+  if (DEBUG) {
+    if (changed) {
+      std::cout << "GlobalStrengthReduction: Function " << func->getName() << " was modified" << std::endl;
+    } else {
+      std::cout << "GlobalStrengthReduction: Function " << func->getName() << " was not modified" << std::endl;
+    }
+    std::cout << "=== GlobalStrengthReduction completed for function: " << func->getName() << " ===" << std::endl;
+  }
+
+  return changed;
+}
+
+void GlobalStrengthReduction::getAnalysisUsage(std::set<void *> &analysisDependencies, std::set<void *> &analysisInvalidations) const {
+  // 强度削弱依赖副作用分析来判断指令是否可以安全优化
+  analysisDependencies.insert(&SysYSideEffectAnalysisPass::ID);
+  
+  // 强度削弱不会使分析失效，因为：
+  // - 只替换计算指令，不改变控制流
+  // - 不修改内存，不影响别名分析
+  // - 保持程序语义不变
+  // analysisInvalidations 保持为空
+  
+  if (DEBUG) {
+    std::cout << "GlobalStrengthReduction: Declared analysis dependencies (SideEffectAnalysis)" << std::endl;
+  }
+}
+
+// ======================================================================
+// GlobalStrengthReductionContext 类的实现
+// ======================================================================
+
+void GlobalStrengthReductionContext::run(Function *func, AnalysisManager *AM, bool &changed) {
+  if (DEBUG) {
+    std::cout << "  Starting GlobalStrengthReduction analysis for function: " << func->getName() << std::endl;
+  }
+
+  // 获取分析结果
+  if (AM) {
+    sideEffectAnalysis = AM->getAnalysisResult<SideEffectAnalysisResult, SysYSideEffectAnalysisPass>();
+    
+    if (DEBUG) {
+      if (sideEffectAnalysis) {
+        std::cout << "    GlobalStrengthReduction: Using side effect analysis" << std::endl;
+      } else {
+        std::cout << "    GlobalStrengthReduction: Warning - side effect analysis not available" << std::endl;
+      }
+    }
+  }
+
+  // 重置计数器
+  algebraicOptCount = 0;
+  strengthReductionCount = 0;
+  divisionOptCount = 0;
+
+  // 遍历所有基本块进行优化
+  for (auto &bb_ptr : func->getBasicBlocks()) {
+    if (processBasicBlock(bb_ptr.get())) {
+      changed = true;
+    }
+  }
+
+  if (DEBUG) {
+    std::cout << "  GlobalStrengthReduction completed for function: " << func->getName() << std::endl;
+    std::cout << "    Algebraic optimizations: " << algebraicOptCount << std::endl;
+    std::cout << "    Strength reductions: " << strengthReductionCount << std::endl;
+    std::cout << "    Division optimizations: " << divisionOptCount << std::endl;
+  }
+}
+
+bool GlobalStrengthReductionContext::processBasicBlock(BasicBlock *bb) {
+  bool changed = false;
+  
+  if (DEBUG) {
+    std::cout << "    Processing block: " << bb->getName() << std::endl;
+  }
+
+  // 收集需要处理的指令（避免迭代器失效）
+  std::vector<Instruction*> instructions;
+  for (auto &inst_ptr : bb->getInstructions()) {
+    instructions.push_back(inst_ptr.get());
+  }
+
+  // 处理每条指令
+  for (auto inst : instructions) {
+    if (processInstruction(inst)) {
+      changed = true;
+    }
+  }
+
+  return changed;
+}
+
+bool GlobalStrengthReductionContext::processInstruction(Instruction *inst) {
+
+  if (DEBUG) {
+    std::cout << "      Processing instruction: " << inst->getName() << std::endl;
+  }
+
+  // 先尝试代数优化
+  if (tryAlgebraicOptimization(inst)) {
+    algebraicOptCount++;
+    return true;
+  }
+
+  // 再尝试强度削弱
+  if (tryStrengthReduction(inst)) {
+    strengthReductionCount++;
+    return true;
+  }
+
+  return false;
+}
+
+// ======================================================================
+// 代数优化方法
+// ======================================================================
+
+bool GlobalStrengthReductionContext::tryAlgebraicOptimization(Instruction *inst) {
+  auto binary = dynamic_cast<BinaryInst*>(inst);
+  if (!binary) {
+    return false;
+  }
+
+  switch (binary->getKind()) {
+    case Instruction::kAdd:
+      return optimizeAddition(binary);
+    case Instruction::kSub:
+      return optimizeSubtraction(binary);
+    case Instruction::kMul:
+      return optimizeMultiplication(binary);
+    case Instruction::kDiv:
+      return optimizeDivision(binary);
+    case Instruction::kICmpEQ:
+    case Instruction::kICmpNE:
+    case Instruction::kICmpLT:
+    case Instruction::kICmpGT:
+    case Instruction::kICmpLE:
+    case Instruction::kICmpGE:
+      return optimizeComparison(binary);
+    case Instruction::kAnd:
+    case Instruction::kOr:
+      return optimizeLogical(binary);
+    default:
+      return false;
+  }
+}
+
+bool GlobalStrengthReductionContext::optimizeAddition(BinaryInst *inst) {
+  Value *lhs = inst->getLhs();
+  Value *rhs = inst->getRhs();
+  int constVal;
+
+  // x + 0 = x
+  if (isConstantInt(rhs, constVal) && constVal == 0) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x + 0 -> x" << std::endl;
+    }
+    replaceWithOptimized(inst, lhs);
+    return true;
+  }
+  
+  // 0 + x = x
+  if (isConstantInt(lhs, constVal) && constVal == 0) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = 0 + x -> x" << std::endl;
+    }
+    replaceWithOptimized(inst, rhs);
+    return true;
+  }
+
+  // x + (-y) = x - y
+  if (auto rhsInst = dynamic_cast<UnaryInst*>(rhs)) {
+    if (rhsInst->getKind() == Instruction::kNeg) {
+      if (DEBUG) {
+        std::cout << "        Algebraic: " << inst->getName() << " = x + (-y) -> x - y" << std::endl;
+      }
+      // 创建减法指令
+      builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+      auto subInst = builder->createSubInst(lhs, rhsInst->getOperand());
+      replaceWithOptimized(inst, subInst);
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool GlobalStrengthReductionContext::optimizeSubtraction(BinaryInst *inst) {
+  Value *lhs = inst->getLhs();
+  Value *rhs = inst->getRhs();
+  int constVal;
+
+  // x - 0 = x
+  if (isConstantInt(rhs, constVal) && constVal == 0) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x - 0 -> x" << std::endl;
+    }
+    replaceWithOptimized(inst, lhs);
+    return true;
+  }
+
+  // x - x = 0 (如果x没有副作用)
+  if (lhs == rhs && hasOnlyLocalUses(dynamic_cast<Instruction*>(lhs))) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x - x -> 0" << std::endl;
+    }
+    replaceWithOptimized(inst, getConstantInt(0));
+    return true;
+  }
+
+  // x - (-y) = x + y
+  if (auto rhsInst = dynamic_cast<UnaryInst*>(rhs)) {
+    if (rhsInst->getKind() == Instruction::kNeg) {
+      if (DEBUG) {
+        std::cout << "        Algebraic: " << inst->getName() << " = x - (-y) -> x + y" << std::endl;
+      }
+      builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+      auto addInst = builder->createAddInst(lhs, rhsInst->getOperand());
+      replaceWithOptimized(inst, addInst);
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool GlobalStrengthReductionContext::optimizeMultiplication(BinaryInst *inst) {
+  Value *lhs = inst->getLhs();
+  Value *rhs = inst->getRhs();
+  int constVal;
+
+  // x * 0 = 0
+  if (isConstantInt(rhs, constVal) && constVal == 0) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x * 0 -> 0" << std::endl;
+    }
+    replaceWithOptimized(inst, getConstantInt(0));
+    return true;
+  }
+  
+  // 0 * x = 0
+  if (isConstantInt(lhs, constVal) && constVal == 0) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = 0 * x -> 0" << std::endl;
+    }
+    replaceWithOptimized(inst, getConstantInt(0));
+    return true;
+  }
+
+  // x * 1 = x
+  if (isConstantInt(rhs, constVal) && constVal == 1) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x * 1 -> x" << std::endl;
+    }
+    replaceWithOptimized(inst, lhs);
+    return true;
+  }
+  
+  // 1 * x = x
+  if (isConstantInt(lhs, constVal) && constVal == 1) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = 1 * x -> x" << std::endl;
+    }
+    replaceWithOptimized(inst, rhs);
+    return true;
+  }
+
+  // x * (-1) = -x
+  if (isConstantInt(rhs, constVal) && constVal == -1) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x * (-1) -> -x" << std::endl;
+    }
+    builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+    auto negInst = builder->createNegInst(lhs);
+    replaceWithOptimized(inst, negInst);
+    return true;
+  }
+
+  return false;
+}
+
+bool GlobalStrengthReductionContext::optimizeDivision(BinaryInst *inst) {
+  Value *lhs = inst->getLhs();
+  Value *rhs = inst->getRhs();
+  int constVal;
+
+  // x / 1 = x
+  if (isConstantInt(rhs, constVal) && constVal == 1) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x / 1 -> x" << std::endl;
+    }
+    replaceWithOptimized(inst, lhs);
+    return true;
+  }
+
+  // x / (-1) = -x
+  if (isConstantInt(rhs, constVal) && constVal == -1) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x / (-1) -> -x" << std::endl;
+    }
+    builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+    auto negInst = builder->createNegInst(lhs);
+    replaceWithOptimized(inst, negInst);
+    return true;
+  }
+
+  // x / x = 1 (如果x != 0且没有副作用)
+  if (lhs == rhs && hasOnlyLocalUses(dynamic_cast<Instruction*>(lhs))) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x / x -> 1" << std::endl;
+    }
+    replaceWithOptimized(inst, getConstantInt(1));
+    return true;
+  }
+
+  return false;
+}
+
+bool GlobalStrengthReductionContext::optimizeComparison(BinaryInst *inst) {
+  Value *lhs = inst->getLhs();
+  Value *rhs = inst->getRhs();
+
+  // x == x = true (如果x没有副作用)
+  if (inst->getKind() == Instruction::kICmpEQ && lhs == rhs && 
+      hasOnlyLocalUses(dynamic_cast<Instruction*>(lhs))) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x == x -> true" << std::endl;
+    }
+    replaceWithOptimized(inst, getConstantInt(1));
+    return true;
+  }
+
+  // x != x = false (如果x没有副作用)
+  if (inst->getKind() == Instruction::kICmpNE && lhs == rhs && 
+      hasOnlyLocalUses(dynamic_cast<Instruction*>(lhs))) {
+    if (DEBUG) {
+      std::cout << "        Algebraic: " << inst->getName() << " = x != x -> false" << std::endl;
+    }
+    replaceWithOptimized(inst, getConstantInt(0));
+    return true;
+  }
+
+  return false;
+}
+
+bool GlobalStrengthReductionContext::optimizeLogical(BinaryInst *inst) {
+  Value *lhs = inst->getLhs();
+  Value *rhs = inst->getRhs();
+  int constVal;
+
+  if (inst->getKind() == Instruction::kAnd) {
+    // x && 0 = 0
+    if (isConstantInt(rhs, constVal) && constVal == 0) {
+      if (DEBUG) {
+        std::cout << "        Algebraic: " << inst->getName() << " = x && 0 -> 0" << std::endl;
+      }
+      replaceWithOptimized(inst, getConstantInt(0));
+      return true;
+    }
+    
+    // x && -1 = x
+    if (isConstantInt(rhs, constVal) && constVal == -1) {
+      if (DEBUG) {
+        std::cout << "        Algebraic: " << inst->getName() << " = x && 1 -> x" << std::endl;
+      }
+      replaceWithOptimized(inst, lhs);
+      return true;
+    }
+
+    // x && x = x
+    if (lhs == rhs) {
+      if (DEBUG) {
+        std::cout << "        Algebraic: " << inst->getName() << " = x && x -> x" << std::endl;
+      }
+      replaceWithOptimized(inst, lhs);
+      return true;
+    }
+  } else if (inst->getKind() == Instruction::kOr) {
+    // x || 0 = x
+    if (isConstantInt(rhs, constVal) && constVal == 0) {
+      if (DEBUG) {
+        std::cout << "        Algebraic: " << inst->getName() << " = x || 0 -> x" << std::endl;
+      }
+      replaceWithOptimized(inst, lhs);
+      return true;
+    }
+
+    // x || x = x
+    if (lhs == rhs) {
+      if (DEBUG) {
+        std::cout << "        Algebraic: " << inst->getName() << " = x || x -> x" << std::endl;
+      }
+      replaceWithOptimized(inst, lhs);
+      return true;
+    }
+  }
+
+  return false;
+}
+
+// ======================================================================
+// 强度削弱方法
+// ======================================================================
+
+bool GlobalStrengthReductionContext::tryStrengthReduction(Instruction *inst) {
+  if (auto binary = dynamic_cast<BinaryInst*>(inst)) {
+    switch (binary->getKind()) {
+      case Instruction::kMul:
+        return reduceMultiplication(binary);
+      case Instruction::kDiv:
+        return reduceDivision(binary);
+      default:
+        return false;
+    }
+  } else if (auto call = dynamic_cast<CallInst*>(inst)) {
+    return reducePower(call);
+  }
+
+  return false;
+}
+
+bool GlobalStrengthReductionContext::reduceMultiplication(BinaryInst *inst) {
+  Value *lhs = inst->getLhs();
+  Value *rhs = inst->getRhs();
+  int constVal;
+
+  // 尝试右操作数为常数
+  Value* variable = lhs;
+  if (isConstantInt(rhs, constVal) && constVal > 0) {
+    return tryComplexMultiplication(inst, variable, constVal);
+  }
+  
+  // 尝试左操作数为常数
+  if (isConstantInt(lhs, constVal) && constVal > 0) {
+    variable = rhs;
+    return tryComplexMultiplication(inst, variable, constVal);
+  }
+
+  return false;
+}
+
+bool GlobalStrengthReductionContext::tryComplexMultiplication(BinaryInst* inst, Value* variable, int constant) {
+  // 首先检查是否为2的幂，使用简单位移
+  if (isPowerOfTwo(constant)) {
+    int shiftAmount = log2OfPowerOfTwo(constant);
+    if (DEBUG) {
+      std::cout << "        StrengthReduction: " << inst->getName() 
+                << " = x * " << constant << " -> x << " << shiftAmount << std::endl;
+    }
+    
+    builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+    auto shiftInst = builder->createBinaryInst(Instruction::kSll, Type::getIntType(), variable, getConstantInt(shiftAmount));
+    replaceWithOptimized(inst, shiftInst);
+    return true;
+  }
+  
+  // 尝试分解为位移和加法的组合
+  std::vector<int> shifts;
+  if (findOptimalShiftDecomposition(constant, shifts)) {
+    if (DEBUG) {
+      std::cout << "        StrengthReduction: " << inst->getName() 
+                << " = x * " << constant << " -> shift decomposition with " << shifts.size() << " terms" << std::endl;
+    }
+    
+    Value* result = createShiftDecomposition(inst, variable, shifts);
+    if (result) {
+      replaceWithOptimized(inst, result);
+      return true;
+    }
+  }
+  
+  return false;
+}
+
+bool GlobalStrengthReductionContext::findOptimalShiftDecomposition(int constant, std::vector<int>& shifts) {
+  shifts.clear();
+  
+  // 常见的有效分解模式
+  switch (constant) {
+    case 3:   // 3 = 2^1 + 2^0 -> (x << 1) + x
+      shifts = {1, 0};
+      return true;
+    case 5:   // 5 = 2^2 + 2^0 -> (x << 2) + x  
+      shifts = {2, 0};
+      return true;
+    case 6:   // 6 = 2^2 + 2^1 -> (x << 2) + (x << 1)
+      shifts = {2, 1};
+      return true;
+    case 7:   // 7 = 2^2 + 2^1 + 2^0 -> (x << 2) + (x << 1) + x
+      shifts = {2, 1, 0};
+      return true;
+    case 9:   // 9 = 2^3 + 2^0 -> (x << 3) + x
+      shifts = {3, 0};
+      return true;
+    case 10:  // 10 = 2^3 + 2^1 -> (x << 3) + (x << 1)
+      shifts = {3, 1};
+      return true;
+    case 11:  // 11 = 2^3 + 2^1 + 2^0 -> (x << 3) + (x << 1) + x
+      shifts = {3, 1, 0};
+      return true;
+    case 12:  // 12 = 2^3 + 2^2 -> (x << 3) + (x << 2)
+      shifts = {3, 2};
+      return true;
+    case 13:  // 13 = 2^3 + 2^2 + 2^0 -> (x << 3) + (x << 2) + x
+      shifts = {3, 2, 0};
+      return true;
+    case 14:  // 14 = 2^3 + 2^2 + 2^1 -> (x << 3) + (x << 2) + (x << 1)
+      shifts = {3, 2, 1};
+      return true;
+    case 15:  // 15 = 2^3 + 2^2 + 2^1 + 2^0 -> (x << 3) + (x << 2) + (x << 1) + x
+      shifts = {3, 2, 1, 0};
+      return true;
+    case 17:  // 17 = 2^4 + 2^0 -> (x << 4) + x
+      shifts = {4, 0};
+      return true;
+    case 18:  // 18 = 2^4 + 2^1 -> (x << 4) + (x << 1)
+      shifts = {4, 1};
+      return true;
+    case 20:  // 20 = 2^4 + 2^2 -> (x << 4) + (x << 2)
+      shifts = {4, 2};
+      return true;
+    case 24:  // 24 = 2^4 + 2^3 -> (x << 4) + (x << 3)
+      shifts = {4, 3};
+      return true;
+    case 25:  // 25 = 2^4 + 2^3 + 2^0 -> (x << 4) + (x << 3) + x
+      shifts = {4, 3, 0};
+      return true;
+    case 100: // 100 = 2^6 + 2^5 + 2^2 -> (x << 6) + (x << 5) + (x << 2)
+      shifts = {6, 5, 2};
+      return true;
+  }
+  
+  // 通用二进制分解（最多4个项，避免过度复杂化）
+  if (constant > 0 && constant < 256) {
+    std::vector<int> binaryShifts;
+    int temp = constant;
+    int bit = 0;
+    
+    while (temp > 0 && binaryShifts.size() < 4) {
+      if (temp & 1) {
+        binaryShifts.push_back(bit);
+      }
+      temp >>= 1;
+      bit++;
+    }
+    
+    // 只有当项数不超过3个时才使用二进制分解（比直接乘法更有效）
+    if (binaryShifts.size() <= 3 && binaryShifts.size() >= 2) {
+      shifts = binaryShifts;
+      return true;
+    }
+  }
+  
+  return false;
+}
+
+Value* GlobalStrengthReductionContext::createShiftDecomposition(BinaryInst* inst, Value* variable, const std::vector<int>& shifts) {
+  if (shifts.empty()) return nullptr;
+  
+  builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+  
+  Value* result = nullptr;
+  
+  for (int shift : shifts) {
+    Value* term;
+    if (shift == 0) {
+      // 0位移就是原变量
+      term = variable;
+    } else {
+      // 创建位移指令
+      term = builder->createBinaryInst(Instruction::kSll, Type::getIntType(), variable, getConstantInt(shift));
+    }
+    
+    if (result == nullptr) {
+      result = term;
+    } else {
+      // 累加到结果中
+      result = builder->createAddInst(result, term);
+    }
+  }
+  
+  return result;
+}
+
+bool GlobalStrengthReductionContext::reduceDivision(BinaryInst *inst) {
+  Value *lhs = inst->getLhs();
+  Value *rhs = inst->getRhs();
+  uint32_t constVal;
+
+  // x / 2^n = x >> n (对于无符号除法或已知为正数的情况)
+  if (isConstantInt(rhs, constVal) && constVal > 0 && isPowerOfTwo(constVal)) {
+    builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+    int shiftAmount = log2OfPowerOfTwo(constVal);
+    // 有符号除法校正：(x + (x >> 31) & mask) >> k
+    int maskValue = constVal - 1;
+    
+    // x >> 31 (算术右移获取符号位)
+    Value* signShift = ConstantInteger::get(31);
+    Value* signBits = builder->createBinaryInst(
+      Instruction::Kind::kSra,  // 算术右移
+      lhs->getType(),
+      lhs,
+      signShift
+    );
+    
+    // (x >> 31) & mask
+    Value* mask = ConstantInteger::get(maskValue);
+    Value* correction = builder->createBinaryInst(
+      Instruction::Kind::kAnd,
+      lhs->getType(),
+      signBits,
+      mask
+    );
+    
+    // x + correction
+    Value* corrected = builder->createAddInst(lhs, correction);
+    
+    // (x + correction) >> k
+    Value* divShift = ConstantInteger::get(shiftAmount);
+    Value* shiftInst = builder->createBinaryInst(
+      Instruction::Kind::kSra,  // 算术右移
+      lhs->getType(),
+      corrected,
+      divShift
+    );
+
+    if (DEBUG) {
+      std::cout << "        StrengthReduction: " << inst->getName() 
+                << " = x / " << constVal << " -> (x + (x >> 31) & mask) >> " << shiftAmount << std::endl;
+    }
+    
+    // builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+    // Value* divisor_minus_1 = ConstantInteger::get(constVal - 1);
+    // Value* adjusted = builder->createAddInst(lhs, divisor_minus_1);
+    // Value* shiftInst = builder->createBinaryInst(Instruction::kSra, Type::getIntType(), adjusted, getConstantInt(shiftAmount));
+    replaceWithOptimized(inst, shiftInst);
+    strengthReductionCount++;
+    return true;
+  }
+
+  // x / c = x * magic_number (魔数乘法优化 - 使用libdivide算法)
+  if (isConstantInt(rhs, constVal) && constVal > 1 && constVal != (uint32_t)(-1)) {
+    // auto magicPair = computeMulhMagicNumbers(static_cast<int>(constVal));
+    Value* magicResult = createMagicDivisionLibdivide(inst, static_cast<int>(constVal));
+    replaceWithOptimized(inst, magicResult);
+    divisionOptCount++;
+    return true;
+  }
+
+  return false;
+}
+
+bool GlobalStrengthReductionContext::reducePower(CallInst *inst) {
+  // 检查是否是pow函数调用
+  Function* callee = inst->getCallee();
+  if (!callee || callee->getName() != "pow") {
+    return false;
+  }
+
+  // pow(x, 2) = x * x
+  if (inst->getNumOperands() >= 2) {
+    int exponent;
+    if (isConstantInt(inst->getOperand(1), exponent)) {
+      if (exponent == 2) {
+        if (DEBUG) {
+          std::cout << "        StrengthReduction: pow(x, 2) -> x * x" << std::endl;
+        }
+        
+        Value* base = inst->getOperand(0);
+        builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+        auto mulInst = builder->createMulInst(base, base);
+        replaceWithOptimized(inst, mulInst);
+        strengthReductionCount++;
+        return true;
+      } else if (exponent >= 3 && exponent <= 8) {
+        // 对于小的指数，展开为连续乘法
+        if (DEBUG) {
+          std::cout << "        StrengthReduction: pow(x, " << exponent << ") -> repeated multiplication" << std::endl;
+        }
+        
+        Value* base = inst->getOperand(0);
+        Value* result = base;
+        builder->setPosition(inst->getParent(), inst->getParent()->findInstIterator(inst));
+        
+        for (int i = 1; i < exponent; i++) {
+          result = builder->createMulInst(result, base);
+        }
+        
+        replaceWithOptimized(inst, result);
+        strengthReductionCount++;
+        return true;
+      }
+    }
+  }
+
+  return false;
+}
+
+Value* GlobalStrengthReductionContext::createMagicDivisionLibdivide(BinaryInst* divInst, int divisor) {
+  builder->setPosition(divInst->getParent(), divInst->getParent()->findInstIterator(divInst));
+  // 使用mulh指令优化任意常数除法
+  auto [magic, shift] = SysYIROptUtils::computeMulhMagicNumbers(divisor);
+  
+  // 检查是否无法优化（magic == -1, shift == -1 表示失败）
+  if (magic == -1 && shift == -1) {
+    if (DEBUG) {
+      std::cout << "[SR] Cannot optimize division by " << divisor 
+                << ", keeping original division" << std::endl;
+    }
+    // 返回 nullptr 表示无法优化，调用方应该保持原始除法
+    return nullptr;
+  }
+  
+  // 2的幂次方除法可以用移位优化（但这不是魔数法的情况）这种情况应该不会被分类到这里但是还是做一个保护措施
+  if ((divisor & (divisor - 1)) == 0 && divisor > 0) {
+    // 是2的幂次方，可以用移位
+    int shift_amount = 0;
+    int temp = divisor;
+    while (temp > 1) {
+      temp >>= 1;
+      shift_amount++;
+    }
+    
+    Value* shiftConstant = ConstantInteger::get(shift_amount);
+    // 对于有符号除法，需要先加上除数-1然后再移位（为了正确处理负数舍入）
+    Value* divisor_minus_1 = ConstantInteger::get(divisor - 1);
+    Value* adjusted = builder->createAddInst(divInst->getOperand(0), divisor_minus_1);
+    return builder->createBinaryInst(
+      Instruction::Kind::kSra,  // 算术右移
+      divInst->getOperand(0)->getType(),
+      adjusted,
+      shiftConstant
+    );
+  }
+  
+  // 创建魔数常量
+  // 检查魔数是否能放入32位，如果不能，则不进行优化
+  if (magic > INT32_MAX || magic < INT32_MIN) {
+    if (DEBUG) {
+      std::cout << "[SR] Magic number " << magic << " exceeds 32-bit range, skipping optimization" << std::endl;
+    }
+    return nullptr; // 无法优化，保持原始除法
+  }
+  
+  Value* magicConstant = ConstantInteger::get((int32_t)magic);
+  
+  // 检查是否需要ADD_MARKER处理（加法调整）
+  bool needAdd = (shift & 0x40) != 0;
+  int actualShift = shift & 0x3F; // 提取真实的移位量
+  
+  if (DEBUG) {
+    std::cout << "[SR] IR Generation: magic=" << magic << ", needAdd=" << needAdd 
+              << ", actualShift=" << actualShift << std::endl;
+  }
+  
+  // 执行高位乘法：mulh(x, magic)
+  Value* mulhResult = builder->createBinaryInst(
+    Instruction::Kind::kMulh,  // 高位乘法
+    divInst->getOperand(0)->getType(),
+    divInst->getOperand(0),
+    magicConstant
+  );
+  
+  if (needAdd) {
+    // ADD_MARKER 情况：需要在移位前加上被除数
+    // 这对应于 libdivide 的加法调整算法
+    if (DEBUG) {
+      std::cout << "[SR] Applying ADD_MARKER: adding dividend before shift" << std::endl;
+    }
+    mulhResult = builder->createAddInst(mulhResult, divInst->getOperand(0));
+  }
+  
+  if (actualShift > 0) {
+    // 如果需要额外移位
+    Value* shiftConstant = ConstantInteger::get(actualShift);
+    mulhResult = builder->createBinaryInst(
+      Instruction::Kind::kSra,  // 算术右移
+      divInst->getOperand(0)->getType(),
+      mulhResult,
+      shiftConstant
+    );
+  }
+  
+  // 标准的有符号除法符号修正：如果被除数为负，商需要加1
+  // 这对所有有符号除法都需要，不管是否可能有负数
+  Value* isNegative = builder->createICmpLTInst(divInst->getOperand(0), ConstantInteger::get(0));
+  // 将i1转换为i32：负数时为1，非负数时为0 ICmpLTInst的结果会默认转化为32位
+  mulhResult = builder->createAddInst(mulhResult, isNegative);
+  
+  return mulhResult; 
+}
+
+// ======================================================================
+// 辅助方法
+// ======================================================================
+
+bool GlobalStrengthReductionContext::isPowerOfTwo(uint32_t n) {
+  return n > 0 && (n & (n - 1)) == 0;
+}
+
+int GlobalStrengthReductionContext::log2OfPowerOfTwo(uint32_t n) {
+  int result = 0;
+  while (n > 1) {
+    n >>= 1;
+    result++;
+  }
+  return result;
+}
+
+bool GlobalStrengthReductionContext::isConstantInt(Value* val, int& constVal) {
+  if (auto constInt = dynamic_cast<ConstantInteger*>(val)) {
+    constVal = std::get<int>(constInt->getVal());
+    return true;
+  }
+  return false;
+}
+
+bool GlobalStrengthReductionContext::isConstantInt(Value* val, uint32_t& constVal) {
+  if (auto constInt = dynamic_cast<ConstantInteger*>(val)) {
+    int signedVal = std::get<int>(constInt->getVal());
+    if (signedVal >= 0) {
+      constVal = static_cast<uint32_t>(signedVal);
+      return true;
+    }
+  }
+  return false;
+}
+
+ConstantInteger* GlobalStrengthReductionContext::getConstantInt(int val) {
+  return ConstantInteger::get(val);
+}
+
+bool GlobalStrengthReductionContext::hasOnlyLocalUses(Instruction* inst) {
+  if (!inst) return true;
+  
+  // 简单检查：如果指令没有副作用，则认为是本地的
+  if (sideEffectAnalysis) {
+    auto sideEffect = sideEffectAnalysis->getInstructionSideEffect(inst);
+    return sideEffect.type == SideEffectType::NO_SIDE_EFFECT;
+  }
+  
+  // 没有副作用分析时，保守处理
+  return !inst->isCall() && !inst->isStore() && !inst->isLoad();
+}
+
+void GlobalStrengthReductionContext::replaceWithOptimized(Instruction* original, Value* replacement) {
+  if (DEBUG) {
+    std::cout << "          Replacing " << original->getName() 
+              << " with " << replacement->getName() << std::endl;
+  }
+  
+  original->replaceAllUsesWith(replacement);
+  
+  // 如果替换值是新创建的指令，确保它有合适的名字
+//   if (auto replInst = dynamic_cast<Instruction*>(replacement)) {
+//     if (replInst->getName().empty()) {
+//       replInst->setName(original->getName() + "_opt");
+//     }
+//   }
+  
+  // 删除原指令，让调用者处理
+  SysYIROptUtils::usedelete(original);
+}
+
+} // namespace sysy

src/midend/Pass/Optimize/LoopStrengthReduction.cpp

@@ -106,187 +106,6 @@ bool StrengthReductionContext::analyzeInductionVariableRange(
   return hasNegativePotential;
 }
 
-//该实现参考了libdivide的算法
-std::pair<int, int> StrengthReductionContext::computeMulhMagicNumbers(int divisor) const {
-  
-  if (DEBUG) {
-    std::cout << "\n[SR] ===== Computing magic numbers for divisor " << divisor << " (libdivide algorithm) =====" << std::endl;
-  }
-  
-  if (divisor == 0) {
-    if (DEBUG) std::cout << "[SR] Error: divisor must be != 0" << std::endl;
-    return {-1, -1};
-  }
-
-  // libdivide 常数
-  const uint8_t LIBDIVIDE_ADD_MARKER = 0x40;
-  const uint8_t LIBDIVIDE_NEGATIVE_DIVISOR = 0x80;
-  
-  // 辅助函数：计算前导零个数
-  auto count_leading_zeros32 = [](uint32_t val) -> uint32_t {
-    if (val == 0) return 32;
-    return __builtin_clz(val);
-  };
-  
-  // 辅助函数：64位除法返回32位商和余数
-  auto div_64_32 = [](uint32_t high, uint32_t low, uint32_t divisor, uint32_t* rem) -> uint32_t {
-    uint64_t dividend = ((uint64_t)high << 32) | low;
-    uint32_t quotient = dividend / divisor;
-    *rem = dividend % divisor;
-    return quotient;
-  };
-
-  if (DEBUG) {
-    std::cout << "[SR] Input divisor: " << divisor << std::endl;
-  }
-
-  // libdivide_internal_s32_gen 算法实现
-  int32_t d = divisor;
-  uint32_t ud = (uint32_t)d;
-  uint32_t absD = (d < 0) ? -ud : ud;
-  
-  if (DEBUG) {
-    std::cout << "[SR] absD = " << absD << std::endl;
-  }
-  
-  uint32_t floor_log_2_d = 31 - count_leading_zeros32(absD);
-  
-  if (DEBUG) {
-    std::cout << "[SR] floor_log_2_d = " << floor_log_2_d << std::endl;
-  }
-  
-  // 检查 absD 是否为2的幂
-  if ((absD & (absD - 1)) == 0) {
-    if (DEBUG) {
-      std::cout << "[SR] " << absD << " 是2的幂，使用移位方法" << std::endl;
-    }
-    
-    // 对于2的幂，我们只使用移位，不需要魔数
-    int shift = floor_log_2_d;
-    if (d < 0) shift |= 0x80; // 标记负数
-    
-    if (DEBUG) {
-      std::cout << "[SR] Power of 2 result: magic=0, shift=" << shift << std::endl;
-      std::cout << "[SR] ===== End magic computation =====" << std::endl;
-    }
-    
-    // 对于我们的目的，我们将在IR生成中以不同方式处理2的幂
-    // 返回特殊标记
-    return {0, shift};
-  }
-  
-  if (DEBUG) {
-    std::cout << "[SR] " << absD << " is not a power of 2, computing magic number" << std::endl;
-  }
-  
-  // 非2的幂除数的魔数计算
-  uint8_t more;
-  uint32_t rem, proposed_m;
-  
-  // 计算 proposed_m = floor(2^(floor_log_2_d + 31) / absD)
-  proposed_m = div_64_32((uint32_t)1 << (floor_log_2_d - 1), 0, absD, &rem);
-  const uint32_t e = absD - rem;
-  
-  if (DEBUG) {
-    std::cout << "[SR] proposed_m = " << proposed_m << ", rem = " << rem << ", e = " << e << std::endl;
-  }
-  
-  // 确定是否需要"加法"版本
-  const bool branchfree = false; // 使用分支版本
-  
-  if (!branchfree && e < ((uint32_t)1 << floor_log_2_d)) {
-    // 这个幂次有效
-    more = (uint8_t)(floor_log_2_d - 1);
-    if (DEBUG) {
-      std::cout << "[SR] Using basic algorithm, shift = " << (int)more << std::endl;
-    }
-  } else {
-    // 我们需要上升一个等级
-    proposed_m += proposed_m;
-    const uint32_t twice_rem = rem + rem;
-    if (twice_rem >= absD || twice_rem < rem) {
-      proposed_m += 1;
-    }
-    more = (uint8_t)(floor_log_2_d | LIBDIVIDE_ADD_MARKER);
-    if (DEBUG) {
-      std::cout << "[SR] Using add algorithm, proposed_m = " << proposed_m << ", more = " << (int)more << std::endl;
-    }
-  }
-  
-  proposed_m += 1;
-  int32_t magic = (int32_t)proposed_m;
-  
-  // 处理负除数
-  if (d < 0) {
-    more |= LIBDIVIDE_NEGATIVE_DIVISOR;
-    if (!branchfree) {
-      magic = -magic;
-    }
-    if (DEBUG) {
-      std::cout << "[SR] Negative divisor, magic = " << magic << ", more = " << (int)more << std::endl;
-    }
-  }
-  
-  // 为我们的IR生成提取移位量和标志  
-  int shift = more & 0x3F; // 移除标志，保留移位量（位0-5）
-  bool need_add = (more & LIBDIVIDE_ADD_MARKER) != 0;
-  bool is_negative = (more & LIBDIVIDE_NEGATIVE_DIVISOR) != 0;
-  
-  if (DEBUG) {
-    std::cout << "[SR] Final result: magic = " << magic << ", more = " << (int)more 
-              << " (0x" << std::hex << (int)more << std::dec << ")" << std::endl;
-    std::cout << "[SR] Shift = " << shift << ", need_add = " << need_add 
-              << ", is_negative = " << is_negative << std::endl;
-    
-    // Test the magic number using the correct libdivide algorithm
-    std::cout << "[SR] Testing magic number (libdivide algorithm):" << std::endl;
-    int test_values[] = {1, 7, 37, 100, 999, -1, -7, -37, -100};
-    
-    for (int test_val : test_values) {
-      int64_t quotient;
-      
-      // 实现正确的libdivide算法
-      int64_t product = (int64_t)test_val * magic;
-      int64_t high_bits = product >> 32;
-      
-      if (need_add) {
-        // ADD_MARKER情况：移位前加上被除数
-        // 这是libdivide的关键洞察！
-        high_bits += test_val;
-        quotient = high_bits >> shift;
-      } else {
-        // 正常情况：只是移位
-        quotient = high_bits >> shift;
-      }
-      
-      // 符号修正：这是libdivide有符号除法的关键部分！
-      // 如果被除数为负，商需要加1来匹配C语言的截断除法语义
-      if (test_val < 0) {
-        quotient += 1;
-      }
-      
-      int expected = test_val / divisor;
-      
-      bool correct = (quotient == expected);
-      std::cout << "[SR]   " << test_val << " / " << divisor << " = " << quotient 
-                << " (expected " << expected << ") " << (correct ? "✓" : "✗") << std::endl;
-    }
-    
-    std::cout << "[SR] ===== End magic computation =====" << std::endl;
-  }
-  
-  // 返回魔数、移位量，并在移位中编码ADD_MARKER标志
-  // 我们将使用移位的第6位表示ADD_MARKER，第7位表示负数（如果需要）
-  int encoded_shift = shift;
-  if (need_add) {
-    encoded_shift |= 0x40; // 设置第6位表示ADD_MARKER
-    if (DEBUG) {
-      std::cout << "[SR] Encoding ADD_MARKER in shift: " << encoded_shift << std::endl;
-    }
-  }
-  
-  return {magic, encoded_shift};
-}
 
 bool LoopStrengthReduction::runOnFunction(Function* F, AnalysisManager& AM) {
   if (F->getBasicBlocks().empty()) {
@@ -1018,7 +837,7 @@ Value* StrengthReductionContext::generateConstantDivisionReplacement(
   IRBuilder* builder
 ) const {
   // 使用mulh指令优化任意常数除法
-  auto [magic, shift] = computeMulhMagicNumbers(candidate->multiplier);
+  auto [magic, shift] = SysYIROptUtils::computeMulhMagicNumbers(candidate->multiplier);
   
   // 检查是否无法优化（magic == -1, shift == -1 表示失败）
   if (magic == -1 && shift == -1) {

src/midend/Pass/Optimize/TailCallOpt.cpp

@@ -0,0 +1,125 @@
+#include "TailCallOpt.h"
+#include "IR.h"
+#include "IRBuilder.h"
+#include "SysYIROptUtils.h"
+#include <vector>
+// #include <iostream>
+#include <algorithm>
+
+namespace sysy {
+
+void *TailCallOpt::ID = (void *)&TailCallOpt::ID;
+
+void TailCallOpt::getAnalysisUsage(std::set<void *> &analysisDependencies, std::set<void *> &analysisInvalidations) const {
+  analysisInvalidations.insert(&DominatorTreeAnalysisPass::ID);
+  analysisInvalidations.insert(&LoopAnalysisPass::ID);
+}
+
+bool TailCallOpt::runOnFunction(Function *F, AnalysisManager &AM) {
+  std::vector<CallInst *> tailCallInsts;
+  // 遍历函数的所有基本块
+  for (auto &bb_ptr : F->getBasicBlocks()) {
+    auto BB = bb_ptr.get();
+    if (BB->getInstructions().empty()) continue; // 跳过空基本块
+
+    auto term_iter = BB->terminator();
+    if (term_iter == BB->getInstructions().end()) continue; // 没有终结指令则跳过
+    auto term = (*term_iter).get();
+
+    if (!term || !term->isReturn()) continue; // 不是返回指令则跳过
+    auto retInst = static_cast<ReturnInst *>(term);
+
+    Instruction *prevInst = nullptr;
+    if (BB->getInstructions().size() > 1) {
+        auto it = term_iter;
+        --it; // 获取返回指令前的指令
+        prevInst = (*it).get();
+    }
+
+    if (!prevInst || !prevInst->isCall()) continue; // 前一条不是调用指令则跳过
+    auto callInst = static_cast<CallInst *>(prevInst);
+
+    // 检查是否为尾递归调用：被调用函数与当前函数相同且返回值与调用结果匹配
+    if (callInst->getCallee() == F) {
+  // 对于尾递归，返回值应为调用结果或为 void 类型
+        if (retInst->getReturnValue() == callInst || 
+            (retInst->getReturnValue() == nullptr && callInst->getType()->isVoid())) {
+            tailCallInsts.push_back(callInst);
+        }
+    }
+  }
+
+  if (tailCallInsts.empty()) {
+    return false;
+  }
+
+  // 创建一个新的入口基本块，作为循环的前置块
+  auto original_entry = F->getEntryBlock();
+  auto new_entry = F->addBasicBlock("tco.entry." + F->getName());
+  auto loop_header = F->addBasicBlock("tco.loop_header." + F->getName());
+  
+  // 将原入口块中的所有指令移动到循环头块
+  loop_header->getInstructions().splice(loop_header->end(), original_entry->getInstructions());
+  original_entry->setName("tco.pre_header");
+
+  // 为函数参数创建 phi 节点
+  builder->setPosition(loop_header, loop_header->begin());
+  std::vector<PhiInst *> phis;
+  auto original_args = F->getArguments();
+  for (auto &arg : original_args) {
+    auto phi = builder->createPhiInst(arg->getType(), {}, {}, "tco.phi."+arg->getName());
+    phis.push_back(phi);
+  }
+
+  // 用 phi 节点替换所有原始参数的使用
+  for (size_t i = 0; i < original_args.size(); ++i) {
+    original_args[i]->replaceAllUsesWith(phis[i]);
+  }
+
+  // 设置 phi 节点的输入值
+  for (size_t i = 0; i < phis.size(); ++i) {
+    phis[i]->addIncoming(original_args[i], new_entry);
+  }
+
+  // 连接各个基本块
+  builder->setPosition(original_entry, original_entry->end());
+  builder->createUncondBrInst(new_entry);
+  original_entry->addSuccessor(new_entry);
+  
+  builder->setPosition(new_entry, new_entry->end());
+  builder->createUncondBrInst(loop_header);
+  new_entry->addSuccessor(loop_header);
+  loop_header->addPredecessor(new_entry);
+
+  // 处理每一个尾递归调用
+  for (auto callInst : tailCallInsts) {
+    auto tail_call_block = callInst->getParent();
+    
+  // 收集尾递归调用的参数
+    auto args_range = callInst->getArguments();
+    std::vector<Value*> args;
+    std::transform(args_range.begin(), args_range.end(), std::back_inserter(args), 
+                   [](auto& use_ptr){ return use_ptr->getValue(); });
+
+  // 用新的参数值更新 phi 节点
+    for (size_t i = 0; i < phis.size(); ++i) {
+        phis[i]->addIncoming(args[i], tail_call_block);
+    }
+
+  // 移除原有的调用和返回指令
+    auto term_iter = tail_call_block->terminator();
+    SysYIROptUtils::usedelete(term_iter);
+    auto call_iter = tail_call_block->findInstIterator(callInst);
+    SysYIROptUtils::usedelete(call_iter);
+
+  // 添加跳转回循环头块的分支指令
+    builder->setPosition(tail_call_block, tail_call_block->end());
+    builder->createUncondBrInst(loop_header);
+    tail_call_block->addSuccessor(loop_header);
+    loop_header->addPredecessor(tail_call_block);
+  }
+
+  return true;
+}
+
+} // namespace sysy

src/midend/Pass/Pass.cpp

@@ -18,6 +18,8 @@
 #include "LICM.h"
 #include "LoopStrengthReduction.h"
 #include "InductionVariableElimination.h"
+#include "GlobalStrengthReduction.h"
+#include "TailCallOpt.h"
 #include "Pass.h"
 #include <iostream>
 #include <queue>
@@ -77,7 +79,10 @@ void PassManager::runOptimizationPipeline(Module* moduleIR, IRBuilder* builderIR
     registerOptimizationPass<LICM>(builderIR);
     registerOptimizationPass<LoopStrengthReduction>(builderIR);
     registerOptimizationPass<InductionVariableElimination>();
+
+    registerOptimizationPass<GlobalStrengthReduction>(builderIR);
     registerOptimizationPass<Reg2Mem>(builderIR);
+    registerOptimizationPass<TailCallOpt>(builderIR);
 
     registerOptimizationPass<SCCP>(builderIR);
 
@@ -136,6 +141,16 @@ void PassManager::runOptimizationPipeline(Module* moduleIR, IRBuilder* builderIR
       this->addPass(&GVN::ID);
       this->run();
 
+      this->clearPasses();
+      this->addPass(&TailCallOpt::ID);
+      this->run();
+
+      if(DEBUG) {
+        std::cout << "=== IR After TailCallOpt ===\n";
+        SysYPrinter printer(moduleIR);
+        printer.printIR();
+      }
+
       if(DEBUG) {
         std::cout << "=== IR After GVN Optimizations ===\n";
         printPasses();
@@ -179,9 +194,19 @@ void PassManager::runOptimizationPipeline(Module* moduleIR, IRBuilder* builderIR
         printPasses();
       }
 
-      // this->clearPasses();
-      // this->addPass(&Reg2Mem::ID);
-      // this->run();
+      // 全局强度削弱优化，包括代数优化和魔数除法
+      this->clearPasses();
+      this->addPass(&GlobalStrengthReduction::ID);
+      this->run();
+
+      if(DEBUG) {
+        std::cout << "=== IR After Global Strength Reduction Optimizations ===\n";
+        printPasses();
+      }
+
+      this->clearPasses();
+      this->addPass(&Reg2Mem::ID);
+      this->run();
 
       if(DEBUG) {
         std::cout << "=== IR After Reg2Mem Optimizations ===\n";