diff --git a/include/mir/MIR.h b/include/mir/MIR.h
index e69de29..39c15e2 100644
--- a/include/mir/MIR.h
+++ b/include/mir/MIR.h
@@ -0,0 +1,194 @@
+#pragma once
+
+#include <initializer_list>
+#include <iosfwd>
+#include <memory>
+#include <string>
+#include <vector>
+
+namespace ir {
+class Module;
+}
+
+namespace mir {
+
+class MIRContext {
+ public:
+  MIRContext() = default;
+};
+
+MIRContext& DefaultContext();
+
+enum class PhysReg {
+  W0, W1, W2, W3, W4, W5, W6, W7,
+  W8, W9, W10, W11,
+  X0, X1, X2, X3, X4, X5, X6, X7,
+  X8, X9, X10, X11, X29, X30, SP,
+  S0, S1, S2, S3, S4, S5, S6, S7,  // 单精度浮点寄存器
+  S8, S9, S10
+};
+
+const char* PhysRegName(PhysReg reg);
+
+enum class Opcode {
+  Prologue,
+  Epilogue,
+  MovImm,
+  MovReg,
+  FMovImm,     // 浮点立即数加载
+  FMovReg,     // 浮点寄存器移动
+  LoadStack,
+  StoreStack,
+  LoadStackOffset,   // 加载数组元素：ldr w8, [x29, base_offset + element_offset]
+  StoreStackOffset,  // 存储数组元素：str w8, [x29, base_offset + element_offset]
+  LoadStackAddr,     // 加载栈地址：add x9, x29, #offset（用于数组基址）
+  LoadIndirect,      // 间接加载：ldr w8, [x9]
+  StoreIndirect,     // 间接存储：str w8, [x9]
+  LoadGlobal,
+  StoreGlobal,
+  LoadGlobalAddr,  // 加载全局变量地址（用于数组）
+  AddRI,
+  SubRI,
+  AddRR,
+  SubRR,
+  MulRR,
+  DivRR,
+  ModRR,
+  LsrRI,
+  LslRI,
+  LslRR,   // 逻辑左移（用于 index * 4）
+  FAddRR,  // 浮点加法
+  FSubRR,  // 浮点减法
+  FMulRR,  // 浮点乘法
+  FDivRR,  // 浮点除法
+  FSqrtRR, // 浮点平方根
+  SIToFP,  // 有符号整型转浮点
+  FPToSI,  // 浮点转有符号整型
+  CmpOnlyRR,
+  FCmpOnlyRR,
+  CmpRR,
+  FCmpRR,  // 浮点比较
+  Bl,
+  B,       // 无条件跳转
+  Bcond,   // 条件跳转（基于之前的 cmp）
+  FBcond,  // 浮点条件跳转（基于之前的 fcmp，使用 IEEE 754 兼容的条件码）
+  Cbnz,    // 非零跳转
+  Cbz,     // 零跳转
+  Ret,
+};
+
+class Operand {
+ public:
+  enum class Kind { Reg, Imm, FrameIndex, Symbol };
+
+  static Operand Reg(PhysReg reg);
+  static Operand Imm(int value);
+  static Operand FrameIndex(int index);
+  static Operand Symbol(std::string name);
+
+  Kind GetKind() const { return kind_; }
+  PhysReg GetReg() const { return reg_; }
+  int GetImm() const { return imm_; }
+  int GetFrameIndex() const { return imm_; }
+  const std::string& GetSymbol() const { return symbol_; }
+
+ private:
+  Operand(Kind kind, PhysReg reg, int imm, std::string symbol = "");
+
+  Kind kind_;
+  PhysReg reg_;
+  int imm_;
+  std::string symbol_;
+};
+
+class MachineInstr {
+ public:
+  MachineInstr(Opcode opcode, std::vector<Operand> operands = {});
+
+  Opcode GetOpcode() const { return opcode_; }
+  const std::vector<Operand>& GetOperands() const { return operands_; }
+
+ private:
+  Opcode opcode_;
+  std::vector<Operand> operands_;
+};
+
+struct FrameSlot {
+  int index = 0;
+  int size = 4;
+  int offset = 0;
+};
+
+class MachineBasicBlock {
+ public:
+  explicit MachineBasicBlock(std::string name);
+
+  const std::string& GetName() const { return name_; }
+  std::vector<MachineInstr>& GetInstructions() { return instructions_; }
+  const std::vector<MachineInstr>& GetInstructions() const { return instructions_; }
+
+  MachineInstr& Append(Opcode opcode,
+                       std::initializer_list<Operand> operands = {});
+
+ private:
+  std::string name_;
+  std::vector<MachineInstr> instructions_;
+};
+
+class MachineFunction {
+ public:
+  explicit MachineFunction(std::string name);
+
+  const std::string& GetName() const { return name_; }
+  MachineBasicBlock& GetEntry() { return *blocks_.front(); }
+  const MachineBasicBlock& GetEntry() const { return *blocks_.front(); }
+
+  MachineBasicBlock* CreateBlock(std::string name);
+  MachineBasicBlock* FindBlock(const std::string& name);
+  const std::vector<std::unique_ptr<MachineBasicBlock>>& GetBlocks() const {
+    return blocks_;
+  }
+
+  int CreateFrameIndex(int size = 4);
+  FrameSlot& GetFrameSlot(int index);
+  const FrameSlot& GetFrameSlot(int index) const;
+  const std::vector<FrameSlot>& GetFrameSlots() const { return frame_slots_; }
+
+  int GetFrameSize() const { return frame_size_; }
+  void SetFrameSize(int size) { frame_size_ = size; }
+
+ private:
+  std::string name_;
+  std::vector<std::unique_ptr<MachineBasicBlock>> blocks_;
+  std::vector<FrameSlot> frame_slots_;
+  int frame_size_ = 0;
+};
+
+class MachineModule {
+ public:
+  MachineModule() = default;
+  MachineFunction* CreateFunction(std::string name);
+  const std::vector<std::unique_ptr<MachineFunction>>& GetFunctions() const {
+    return functions_;
+  }
+
+  void AddGlobalVar(std::string name, int init_val, int count, bool is_float,
+                    std::vector<int> init_elems = {});
+  const std::vector<std::tuple<std::string, int, int, bool, std::vector<int>>>&
+  GetGlobalVars() const {
+    return global_vars_;
+  }
+
+ private:
+  std::vector<std::unique_ptr<MachineFunction>> functions_;
+  std::vector<std::tuple<std::string, int, int, bool, std::vector<int>>>
+      global_vars_;  // (name, init, count, is_float, init_elements)
+};
+
+std::unique_ptr<MachineModule> LowerToMIR(const ir::Module& module);
+void RunPeephole(MachineFunction& function);
+void RunRegAlloc(MachineFunction& function);
+void RunFrameLowering(MachineFunction& function);
+void PrintAsm(const MachineModule& module, std::ostream& os);
+
+}  // namespace mir
diff --git a/src/mir/Lowering.cpp b/src/mir/Lowering.cpp
index e69de29..75b1171 100644
--- a/src/mir/Lowering.cpp
+++ b/src/mir/Lowering.cpp
@@ -0,0 +1,1043 @@
+#include "mir/MIR.h"
+
+#include <cstdint>
+#include <cstring>
+#include <stdexcept>
+#include <unordered_map>
+
+#include "ir/IR.h"
+#include "utils/Log.h"
+
+namespace mir {
+namespace {
+
+using ValueSlotMap = std::unordered_map<const ir::Value*, int>;
+
+// GEP 结果：(base_slot_index, byte_offset, global_symbol)
+// - base_slot >= 0: 本地数组，base_slot 是栈槽索引
+// - base_slot = -1: 全局数组，global_symbol 是全局变量名
+// - byte_offset >= 0: 常量索引
+// - byte_offset < 0: 变量索引，编码为 -1 - index_slot
+struct GepInfo {
+  int base_slot;
+  int byte_offset;
+  std::string global_symbol;
+};
+using GepMap = std::unordered_map<const ir::Value*, GepInfo>;
+
+bool IsIntImmediate12(int value) { return value >= 0 && value <= 4095; }
+
+const ir::ConstantInt* TryGetConstInt(const ir::Value* value) {
+  return dynamic_cast<const ir::ConstantInt*>(value);
+}
+
+bool IsPowerOfTwoU32(unsigned value) {
+  return value != 0 && (value & (value - 1)) == 0;
+}
+
+bool TryGetConstBool(const ir::Value* value, bool* out) {
+  if (auto* ci = dynamic_cast<const ir::ConstantInt*>(value)) {
+    *out = ci->GetValue() != 0;
+    return true;
+  }
+  return false;
+}
+
+bool UsedOnlyByLoadStore(const ir::Instruction& inst) {
+  for (const auto& use : inst.GetUses()) {
+    auto* user = dynamic_cast<const ir::Instruction*>(use.GetUser());
+    if (!user) {
+      return false;
+    }
+    auto op = user->GetOpcode();
+    if (op != ir::Opcode::Load && op != ir::Opcode::Store) {
+      return false;
+    }
+  }
+  return true;
+}
+
+int CtzU32(unsigned value) {
+  int n = 0;
+  while ((value & 1u) == 0u) {
+    value >>= 1u;
+    ++n;
+  }
+  return n;
+}
+
+void EmitLslBy2(PhysReg reg, MachineBasicBlock& block) {
+  block.Append(Opcode::LslRI,
+               {Operand::Reg(reg), Operand::Reg(reg), Operand::Imm(2)});
+}
+
+void EmitAddOffset(PhysReg reg, int byte_offset, MachineBasicBlock& block) {
+  if (byte_offset <= 0) {
+    return;
+  }
+  if (IsIntImmediate12(byte_offset)) {
+    block.Append(Opcode::AddRI,
+                 {Operand::Reg(reg), Operand::Reg(reg), Operand::Imm(byte_offset)});
+    return;
+  }
+  block.Append(Opcode::MovImm,
+               {Operand::Reg(PhysReg::W10), Operand::Imm(byte_offset)});
+  block.Append(Opcode::AddRR,
+               {Operand::Reg(reg), Operand::Reg(reg), Operand::Reg(PhysReg::X10)});
+}
+
+bool IsPointerType(const std::shared_ptr<ir::Type>& type) {
+  return type && (type->IsPtrInt32() || type->IsPtrFloat32());
+}
+
+void EmitIntValueToReg(const ir::Value* value, PhysReg target,
+                       const ValueSlotMap& slots, MachineBasicBlock& block) {
+  if (auto* constant = dynamic_cast<const ir::ConstantInt*>(value)) {
+    block.Append(Opcode::MovImm,
+                 {Operand::Reg(target), Operand::Imm(constant->GetValue())});
+    return;
+  }
+
+  // 检查是否是全局变量
+  if (auto* gv = dynamic_cast<const ir::GlobalVariable*>(value)) {
+    block.Append(Opcode::LoadGlobal,
+                 {Operand::Reg(target), Operand::Symbol(gv->GetName())});
+    return;
+  }
+
+  auto it = slots.find(value);
+  if (it == slots.end()) {
+    throw std::runtime_error(
+        FormatError("mir", "找不到值对应的栈槽: " + value->GetName()));
+  }
+
+  block.Append(Opcode::LoadStack,
+               {Operand::Reg(target), Operand::FrameIndex(it->second)});
+}
+
+void EmitFloatValueToReg(const ir::Value* value, PhysReg target,
+                         const ValueSlotMap& slots, MachineBasicBlock& block) {
+  if (auto* constant = dynamic_cast<const ir::ConstantFloat*>(value)) {
+    std::int32_t bits = 0;
+    float fv = constant->GetValue();
+    std::memcpy(&bits, &fv, sizeof(bits));
+    block.Append(Opcode::FMovImm,
+                 {Operand::Reg(target), Operand::Imm(static_cast<int>(bits))});
+    return;
+  }
+
+  auto it = slots.find(value);
+  if (it == slots.end()) {
+    throw std::runtime_error(
+        FormatError("mir", "找不到浮点值对应的栈槽: " + value->GetName()));
+  }
+
+  block.Append(Opcode::LoadStack,
+               {Operand::Reg(target), Operand::FrameIndex(it->second)});
+}
+
+void EmitValueToReg(const ir::Value* value, PhysReg target,
+                    const ValueSlotMap& slots, MachineBasicBlock& block) {
+  if (value->GetType() && value->GetType()->IsFloat32()) {
+    EmitFloatValueToReg(value, target, slots, block);
+    return;
+  }
+  EmitIntValueToReg(value, target, slots, block);
+}
+
+void LowerInstruction(const ir::Instruction& inst, MachineFunction& function,
+                      MachineBasicBlock& block, ValueSlotMap& slots,
+                      GepMap& geps) {
+  switch (inst.GetOpcode()) {
+    case ir::Opcode::Alloca: {
+      auto& alloca = static_cast<const ir::AllocaInst&>(inst);
+      int size = alloca.GetCount() * 4;  // count * sizeof(i32)
+      slots.emplace(&inst, function.CreateFrameIndex(size));
+      return;
+    }
+    case ir::Opcode::Gep: {
+      auto& gep = static_cast<const ir::GepInst&>(inst);
+      auto* base = gep.GetBase();
+      auto* index = gep.GetIndex();
+      const bool only_mem_uses = UsedOnlyByLoadStore(inst);
+
+      // 为 GEP 结果分配一个栈槽（用于存储指针值）
+      int ptr_slot = -1;
+
+      // 检查 base 是什么类型：全局数组、本地数组、还是指针参数
+      if (auto* gv = dynamic_cast<const ir::GlobalVariable*>(base)) {
+        if (!only_mem_uses) {
+          ptr_slot = function.CreateFrameIndex(8);  // 64-bit pointer
+        }
+        // 全局数组
+        if (auto* const_index = dynamic_cast<const ir::ConstantInt*>(index)) {
+          // 常量索引：计算地址并存储
+          int byte_offset = const_index->GetValue() * 4;
+          geps.emplace(&inst, GepInfo{-1, byte_offset, gv->GetName()});
+
+          if (ptr_slot >= 0) {
+            // 计算地址：x9 = &global_array + offset
+            block.Append(Opcode::LoadGlobalAddr,
+                         {Operand::Reg(PhysReg::X9), Operand::Symbol(gv->GetName())});
+            EmitAddOffset(PhysReg::X9, byte_offset, block);
+            block.Append(Opcode::StoreStack,
+                         {Operand::Reg(PhysReg::X9), Operand::FrameIndex(ptr_slot)});
+          }
+        } else {
+          // 变量索引
+          int index_slot = function.CreateFrameIndex();
+          EmitValueToReg(index, PhysReg::W8, slots, block);
+          block.Append(Opcode::StoreStack,
+                       {Operand::Reg(PhysReg::W8), Operand::FrameIndex(index_slot)});
+          geps.emplace(&inst, GepInfo{-1, -1 - index_slot, gv->GetName()});
+
+          if (ptr_slot >= 0) {
+            // 计算地址：x9 = &global_array + (index * 4)
+            block.Append(Opcode::LoadStack,
+                         {Operand::Reg(PhysReg::W10), Operand::FrameIndex(index_slot)});
+            EmitLslBy2(PhysReg::W10, block);
+            block.Append(Opcode::LoadGlobalAddr,
+                         {Operand::Reg(PhysReg::X9), Operand::Symbol(gv->GetName())});
+            block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X9),
+                                         Operand::Reg(PhysReg::X9),
+                                         Operand::Reg(PhysReg::X10)});
+            block.Append(Opcode::StoreStack,
+                         {Operand::Reg(PhysReg::X9), Operand::FrameIndex(ptr_slot)});
+          }
+        }
+        if (ptr_slot >= 0) {
+          slots.emplace(&inst, ptr_slot);
+        }
+        return;
+      }
+
+      // 检查 base 是否在 slots 中（本地变量或参数）
+      auto base_it = slots.find(base);
+      if (base_it == slots.end()) {
+        throw std::runtime_error(
+            FormatError("mir", "GEP base 必须是 alloca、指针参数或全局变量"));
+      }
+
+      // 检查 base 是否是指针参数：如果是 Argument 且类型是指针
+      if (dynamic_cast<const ir::Argument*>(base) && IsPointerType(base->GetType())) {
+        ptr_slot = function.CreateFrameIndex(8);  // 指针参数 GEP 保持地址实体化
+        // 指针参数：从栈加载指针值，然后加上索引
+        if (auto* const_index = dynamic_cast<const ir::ConstantInt*>(index)) {
+          // 常量索引
+          int byte_offset = const_index->GetValue() * 4;
+          // 注意：这里不记录到 geps，因为我们已经计算出最终地址了
+
+          // x9 = 从栈加载指针
+          block.Append(Opcode::LoadStack,
+                       {Operand::Reg(PhysReg::X9), Operand::FrameIndex(base_it->second)});
+          EmitAddOffset(PhysReg::X9, byte_offset, block);
+          block.Append(Opcode::StoreStack,
+                       {Operand::Reg(PhysReg::X9), Operand::FrameIndex(ptr_slot)});
+        } else {
+          // 变量索引
+          int index_slot = function.CreateFrameIndex();
+          EmitValueToReg(index, PhysReg::W8, slots, block);
+          block.Append(Opcode::StoreStack,
+                       {Operand::Reg(PhysReg::W8), Operand::FrameIndex(index_slot)});
+
+          // x9 = 从栈加载指针
+          block.Append(Opcode::LoadStack,
+                       {Operand::Reg(PhysReg::X9), Operand::FrameIndex(base_it->second)});
+          // w10 = index * 4
+          block.Append(Opcode::LoadStack,
+                       {Operand::Reg(PhysReg::W10), Operand::FrameIndex(index_slot)});
+          EmitLslBy2(PhysReg::W10, block);
+          // x9 = x9 + w10
+          block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X9),
+                                       Operand::Reg(PhysReg::X9),
+                                       Operand::Reg(PhysReg::X10)});
+          block.Append(Opcode::StoreStack,
+                       {Operand::Reg(PhysReg::X9), Operand::FrameIndex(ptr_slot)});
+        }
+        slots.emplace(&inst, ptr_slot);
+        return;
+      }
+
+      // 本地数组（alloca 的结果）
+      if (!only_mem_uses) {
+        ptr_slot = function.CreateFrameIndex(8);  // 64-bit pointer
+      }
+      // 检查是否是常量索引
+      if (auto* const_index = dynamic_cast<const ir::ConstantInt*>(index)) {
+        int byte_offset = const_index->GetValue() * 4;
+        geps.emplace(&inst, GepInfo{base_it->second, byte_offset, ""});
+
+        if (ptr_slot >= 0) {
+          // 计算地址：x9 = &array_base + byte_offset
+          block.Append(Opcode::LoadStackAddr,
+                       {Operand::Reg(PhysReg::X9), Operand::FrameIndex(base_it->second)});
+          EmitAddOffset(PhysReg::X9, byte_offset, block);
+          block.Append(Opcode::StoreStack,
+                       {Operand::Reg(PhysReg::X9), Operand::FrameIndex(ptr_slot)});
+        }
+      } else {
+        // 变量索引
+        int index_slot = function.CreateFrameIndex();
+        EmitValueToReg(index, PhysReg::W8, slots, block);
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::W8), Operand::FrameIndex(index_slot)});
+        geps.emplace(&inst, GepInfo{base_it->second, -1 - index_slot, ""});
+
+        if (ptr_slot >= 0) {
+          // 计算地址：x9 = x29 + base_offset + (index * 4)
+          block.Append(Opcode::LoadStack,
+                       {Operand::Reg(PhysReg::W10), Operand::FrameIndex(index_slot)});
+          EmitLslBy2(PhysReg::W10, block);
+          block.Append(Opcode::LoadStackAddr,
+                       {Operand::Reg(PhysReg::X9), Operand::FrameIndex(base_it->second)});
+          block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X9),
+                                       Operand::Reg(PhysReg::X9),
+                                       Operand::Reg(PhysReg::X10)});
+          block.Append(Opcode::StoreStack,
+                       {Operand::Reg(PhysReg::X9), Operand::FrameIndex(ptr_slot)});
+        }
+      }
+      if (ptr_slot >= 0) {
+        slots.emplace(&inst, ptr_slot);
+      }
+      return;
+    }
+    case ir::Opcode::Store: {
+      auto& store = static_cast<const ir::StoreInst&>(inst);
+      auto* ptr = store.GetPtr();
+      const bool is_float_value =
+          store.GetValue()->GetType() && store.GetValue()->GetType()->IsFloat32();
+      const PhysReg src_reg = is_float_value ? PhysReg::S0 : PhysReg::W8;
+
+      // 检查是否是 GEP 结果（数组元素）
+      auto gep_it = geps.find(ptr);
+      if (gep_it != geps.end()) {
+        const auto& gep_info = gep_it->second;
+        EmitValueToReg(store.GetValue(), src_reg, slots, block);
+
+        if (gep_info.base_slot == -1) {
+          // 全局数组
+          if (gep_info.byte_offset >= 0) {
+            // 常量索引：global_array[const_idx]
+            // adrp x9, symbol; add x9, x9, :lo12:symbol; add x9, x9, #offset; str w8, [x9]
+            block.Append(Opcode::LoadGlobalAddr,
+                         {Operand::Reg(PhysReg::X9), Operand::Symbol(gep_info.global_symbol)});
+            EmitAddOffset(PhysReg::X9, gep_info.byte_offset, block);
+            block.Append(Opcode::StoreIndirect,
+                         {Operand::Reg(src_reg), Operand::Reg(PhysReg::X9)});
+          } else {
+            // 变量索引：global_array[var_idx]
+            int index_slot = -1 - gep_info.byte_offset;
+            // 1. 加载 index
+            block.Append(Opcode::LoadStack,
+                         {Operand::Reg(PhysReg::W10), Operand::FrameIndex(index_slot)});
+            // 2. index * 4
+            EmitLslBy2(PhysReg::W10, block);
+            // 3. 获取全局数组基址
+            block.Append(Opcode::LoadGlobalAddr,
+                         {Operand::Reg(PhysReg::X9), Operand::Symbol(gep_info.global_symbol)});
+            // 4. x9 + offset
+            block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X9),
+                                         Operand::Reg(PhysReg::X9),
+                                         Operand::Reg(PhysReg::X10)});
+            // 5. 存储
+            block.Append(Opcode::StoreIndirect,
+                         {Operand::Reg(src_reg), Operand::Reg(PhysReg::X9)});
+          }
+        } else if (gep_info.byte_offset >= 0) {
+          // 本地数组，常量索引
+          block.Append(Opcode::StoreStackOffset,
+                       {Operand::Reg(src_reg),
+                        Operand::FrameIndex(gep_info.base_slot),
+                        Operand::Imm(gep_info.byte_offset)});
+        } else {
+          // 本地数组，变量索引
+          int index_slot = -1 - gep_info.byte_offset;
+          block.Append(Opcode::LoadStack,
+                       {Operand::Reg(PhysReg::W10), Operand::FrameIndex(index_slot)});
+          EmitLslBy2(PhysReg::W10, block);
+          block.Append(Opcode::LoadStackAddr,
+                       {Operand::Reg(PhysReg::X9),
+                        Operand::FrameIndex(gep_info.base_slot)});
+          block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X9),
+                                       Operand::Reg(PhysReg::X9),
+                                       Operand::Reg(PhysReg::X10)});
+          block.Append(Opcode::StoreIndirect,
+                       {Operand::Reg(src_reg), Operand::Reg(PhysReg::X9)});
+        }
+        return;
+      }
+
+      // 检查是否是全局变量
+      if (auto* gv = dynamic_cast<const ir::GlobalVariable*>(ptr)) {
+        EmitValueToReg(store.GetValue(), src_reg, slots, block);
+        block.Append(Opcode::StoreGlobal,
+                     {Operand::Reg(src_reg), Operand::Symbol(gv->GetName())});
+        return;
+      }
+
+      // 栈变量或GEP结果
+      auto dst = slots.find(ptr);
+      if (dst == slots.end()) {
+        throw std::runtime_error(
+            FormatError("mir", "暂不支持对非栈/全局变量地址进行写入"));
+      }
+
+      EmitValueToReg(store.GetValue(), src_reg, slots, block);
+
+      // 检查是否是GEP结果：如果ptr的类型是指针且slot大小是8字节，说明存储的是地址
+      const auto& dst_slot = function.GetFrameSlot(dst->second);
+      if (IsPointerType(ptr->GetType()) && dst_slot.size == 8) {
+        // GEP结果：先加载指针地址，再通过指针存储值
+        block.Append(Opcode::LoadStack,
+                     {Operand::Reg(PhysReg::X9), Operand::FrameIndex(dst->second)});
+        block.Append(Opcode::StoreIndirect,
+                     {Operand::Reg(src_reg), Operand::Reg(PhysReg::X9)});
+      } else {
+        // 普通栈变量：直接存储
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(src_reg), Operand::FrameIndex(dst->second)});
+      }
+      return;
+    }
+    case ir::Opcode::Load: {
+      auto& load = static_cast<const ir::LoadInst&>(inst);
+      auto* ptr = load.GetPtr();
+      const bool is_float_load = load.GetType() && load.GetType()->IsFloat32();
+      const PhysReg value_reg = is_float_load ? PhysReg::S0 : PhysReg::W8;
+
+      // 检查是否是 GEP 结果（数组元素）
+      auto gep_it = geps.find(ptr);
+      if (gep_it != geps.end()) {
+        const auto& gep_info = gep_it->second;
+        int dst_slot = function.CreateFrameIndex();
+
+        if (gep_info.base_slot == -1) {
+          // 全局数组
+          if (gep_info.byte_offset >= 0) {
+            // 常量索引
+            block.Append(Opcode::LoadGlobalAddr,
+                         {Operand::Reg(PhysReg::X9), Operand::Symbol(gep_info.global_symbol)});
+            EmitAddOffset(PhysReg::X9, gep_info.byte_offset, block);
+            block.Append(Opcode::LoadIndirect,
+                         {Operand::Reg(value_reg), Operand::Reg(PhysReg::X9)});
+          } else {
+            // 变量索引
+            int index_slot = -1 - gep_info.byte_offset;
+            block.Append(Opcode::LoadStack,
+                         {Operand::Reg(PhysReg::W10), Operand::FrameIndex(index_slot)});
+            EmitLslBy2(PhysReg::W10, block);
+            block.Append(Opcode::LoadGlobalAddr,
+                         {Operand::Reg(PhysReg::X9), Operand::Symbol(gep_info.global_symbol)});
+            block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X9),
+                                         Operand::Reg(PhysReg::X9),
+                                         Operand::Reg(PhysReg::X10)});
+            block.Append(Opcode::LoadIndirect,
+                         {Operand::Reg(value_reg), Operand::Reg(PhysReg::X9)});
+          }
+        } else if (gep_info.byte_offset >= 0) {
+          // 本地数组，常量索引
+          block.Append(Opcode::LoadStackOffset,
+                       {Operand::Reg(value_reg),
+                        Operand::FrameIndex(gep_info.base_slot),
+                        Operand::Imm(gep_info.byte_offset)});
+        } else {
+          // 本地数组，变量索引
+          int index_slot = -1 - gep_info.byte_offset;
+          block.Append(Opcode::LoadStack,
+                       {Operand::Reg(PhysReg::W10), Operand::FrameIndex(index_slot)});
+          EmitLslBy2(PhysReg::W10, block);
+          block.Append(Opcode::LoadStackAddr,
+                       {Operand::Reg(PhysReg::X9),
+                        Operand::FrameIndex(gep_info.base_slot)});
+          block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X9),
+                                       Operand::Reg(PhysReg::X9),
+                                       Operand::Reg(PhysReg::X10)});
+          block.Append(Opcode::LoadIndirect,
+                       {Operand::Reg(value_reg), Operand::Reg(PhysReg::X9)});
+        }
+
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(value_reg), Operand::FrameIndex(dst_slot)});
+        slots.emplace(&inst, dst_slot);
+        return;
+      }
+
+      // 检查是否是全局变量
+      if (auto* gv = dynamic_cast<const ir::GlobalVariable*>(ptr)) {
+        int dst_slot = function.CreateFrameIndex();
+        block.Append(Opcode::LoadGlobal,
+                     {Operand::Reg(value_reg), Operand::Symbol(gv->GetName())});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(value_reg), Operand::FrameIndex(dst_slot)});
+        slots.emplace(&inst, dst_slot);
+        return;
+      }
+
+      // 栈变量或GEP结果
+      auto src = slots.find(ptr);
+      if (src == slots.end()) {
+        throw std::runtime_error(
+            FormatError("mir", "暂不支持对非栈/全局变量地址进行读取"));
+      }
+
+      int dst_slot = function.CreateFrameIndex();
+
+      // 检查是否是GEP结果：如果ptr的类型是指针且slot大小是8字节，说明存储的是地址
+      const auto& src_slot = function.GetFrameSlot(src->second);
+      if (IsPointerType(ptr->GetType()) && src_slot.size == 8) {
+        // GEP结果：先加载指针地址，再通过指针加载值
+        block.Append(Opcode::LoadStack,
+                     {Operand::Reg(PhysReg::X9), Operand::FrameIndex(src->second)});
+        block.Append(Opcode::LoadIndirect,
+                     {Operand::Reg(value_reg), Operand::Reg(PhysReg::X9)});
+      } else {
+        // 普通栈变量：直接加载
+        block.Append(Opcode::LoadStack,
+                     {Operand::Reg(value_reg), Operand::FrameIndex(src->second)});
+      }
+
+      block.Append(Opcode::StoreStack,
+                   {Operand::Reg(value_reg), Operand::FrameIndex(dst_slot)});
+      slots.emplace(&inst, dst_slot);
+      return;
+    }
+    case ir::Opcode::Add: {
+      auto& bin = static_cast<const ir::BinaryInst&>(inst);
+      int dst_slot = function.CreateFrameIndex();
+      if (bin.GetType()->IsFloat32()) {
+        EmitValueToReg(bin.GetLhs(), PhysReg::S0, slots, block);
+        EmitValueToReg(bin.GetRhs(), PhysReg::S1, slots, block);
+        block.Append(Opcode::FAddRR, {Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S1)});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::S0), Operand::FrameIndex(dst_slot)});
+      } else {
+        auto* lhs_ci = TryGetConstInt(bin.GetLhs());
+        auto* rhs_ci = TryGetConstInt(bin.GetRhs());
+
+        if (rhs_ci && !lhs_ci) {
+          EmitValueToReg(bin.GetLhs(), PhysReg::W8, slots, block);
+          int c = rhs_ci->GetValue();
+          if (c != 0) {
+            if (IsIntImmediate12(c)) {
+              block.Append(Opcode::AddRI, {Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W8),
+                                           Operand::Imm(c)});
+            } else {
+              block.Append(Opcode::MovImm,
+                           {Operand::Reg(PhysReg::W9), Operand::Imm(c)});
+              block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W9)});
+            }
+          }
+        } else if (lhs_ci && !rhs_ci) {
+          EmitValueToReg(bin.GetRhs(), PhysReg::W8, slots, block);
+          int c = lhs_ci->GetValue();
+          if (c != 0) {
+            if (IsIntImmediate12(c)) {
+              block.Append(Opcode::AddRI, {Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W8),
+                                           Operand::Imm(c)});
+            } else {
+              block.Append(Opcode::MovImm,
+                           {Operand::Reg(PhysReg::W9), Operand::Imm(c)});
+              block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W9)});
+            }
+          }
+        } else {
+          EmitValueToReg(bin.GetLhs(), PhysReg::W8, slots, block);
+          EmitValueToReg(bin.GetRhs(), PhysReg::W9, slots, block);
+          block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::W8),
+                                       Operand::Reg(PhysReg::W8),
+                                       Operand::Reg(PhysReg::W9)});
+        }
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::W8), Operand::FrameIndex(dst_slot)});
+      }
+      slots.emplace(&inst, dst_slot);
+      return;
+    }
+    case ir::Opcode::Sub: {
+      auto& bin = static_cast<const ir::BinaryInst&>(inst);
+      int dst_slot = function.CreateFrameIndex();
+      if (bin.GetType()->IsFloat32()) {
+        EmitValueToReg(bin.GetLhs(), PhysReg::S0, slots, block);
+        EmitValueToReg(bin.GetRhs(), PhysReg::S1, slots, block);
+        block.Append(Opcode::FSubRR, {Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S1)});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::S0), Operand::FrameIndex(dst_slot)});
+      } else {
+        auto* rhs_ci = TryGetConstInt(bin.GetRhs());
+        auto* lhs_ci = TryGetConstInt(bin.GetLhs());
+
+        if (rhs_ci && !lhs_ci) {
+          EmitValueToReg(bin.GetLhs(), PhysReg::W8, slots, block);
+          int c = rhs_ci->GetValue();
+          if (c != 0) {
+            if (IsIntImmediate12(c)) {
+              block.Append(Opcode::SubRI, {Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W8),
+                                           Operand::Imm(c)});
+            } else {
+              block.Append(Opcode::MovImm,
+                           {Operand::Reg(PhysReg::W9), Operand::Imm(c)});
+              block.Append(Opcode::SubRR, {Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W8),
+                                           Operand::Reg(PhysReg::W9)});
+            }
+          }
+        } else if (lhs_ci && !rhs_ci) {
+          int c = lhs_ci->GetValue();
+          block.Append(Opcode::MovImm,
+                       {Operand::Reg(PhysReg::W8), Operand::Imm(c)});
+          EmitValueToReg(bin.GetRhs(), PhysReg::W9, slots, block);
+          block.Append(Opcode::SubRR, {Operand::Reg(PhysReg::W8),
+                                       Operand::Reg(PhysReg::W8),
+                                       Operand::Reg(PhysReg::W9)});
+        } else {
+          EmitValueToReg(bin.GetLhs(), PhysReg::W8, slots, block);
+          EmitValueToReg(bin.GetRhs(), PhysReg::W9, slots, block);
+          block.Append(Opcode::SubRR, {Operand::Reg(PhysReg::W8),
+                                       Operand::Reg(PhysReg::W8),
+                                       Operand::Reg(PhysReg::W9)});
+        }
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::W8), Operand::FrameIndex(dst_slot)});
+      }
+      slots.emplace(&inst, dst_slot);
+      return;
+    }
+    case ir::Opcode::Mul: {
+      auto& bin = static_cast<const ir::BinaryInst&>(inst);
+      int dst_slot = function.CreateFrameIndex();
+      if (bin.GetType()->IsFloat32()) {
+        EmitValueToReg(bin.GetLhs(), PhysReg::S0, slots, block);
+        EmitValueToReg(bin.GetRhs(), PhysReg::S1, slots, block);
+        block.Append(Opcode::FMulRR, {Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S1)});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::S0), Operand::FrameIndex(dst_slot)});
+      } else {
+        auto* lhs_ci = TryGetConstInt(bin.GetLhs());
+        auto* rhs_ci = TryGetConstInt(bin.GetRhs());
+
+        const ir::Value* non_const = nullptr;
+        const ir::ConstantInt* ci = nullptr;
+        if (lhs_ci && !rhs_ci) {
+          ci = lhs_ci;
+          non_const = bin.GetRhs();
+        } else if (rhs_ci && !lhs_ci) {
+          ci = rhs_ci;
+          non_const = bin.GetLhs();
+        }
+
+        if (ci && non_const) {
+          int c = ci->GetValue();
+          if (c == 0) {
+            block.Append(Opcode::MovImm,
+                         {Operand::Reg(PhysReg::W8), Operand::Imm(0)});
+          } else if (c == 1) {
+            EmitValueToReg(non_const, PhysReg::W8, slots, block);
+          } else if (c > 0 && IsPowerOfTwoU32(static_cast<unsigned>(c))) {
+            EmitValueToReg(non_const, PhysReg::W8, slots, block);
+            int sh = CtzU32(static_cast<unsigned>(c));
+            block.Append(Opcode::LslRI, {Operand::Reg(PhysReg::W8),
+                                         Operand::Reg(PhysReg::W8),
+                                         Operand::Imm(sh)});
+          } else {
+            EmitValueToReg(non_const, PhysReg::W8, slots, block);
+            block.Append(Opcode::MovImm,
+                         {Operand::Reg(PhysReg::W9), Operand::Imm(c)});
+            block.Append(Opcode::MulRR, {Operand::Reg(PhysReg::W8),
+                                         Operand::Reg(PhysReg::W8),
+                                         Operand::Reg(PhysReg::W9)});
+          }
+        } else {
+          EmitValueToReg(bin.GetLhs(), PhysReg::W8, slots, block);
+          EmitValueToReg(bin.GetRhs(), PhysReg::W9, slots, block);
+          block.Append(Opcode::MulRR, {Operand::Reg(PhysReg::W8),
+                                       Operand::Reg(PhysReg::W8),
+                                       Operand::Reg(PhysReg::W9)});
+        }
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::W8), Operand::FrameIndex(dst_slot)});
+      }
+      slots.emplace(&inst, dst_slot);
+      return;
+    }
+    case ir::Opcode::Div: {
+      auto& bin = static_cast<const ir::BinaryInst&>(inst);
+      int dst_slot = function.CreateFrameIndex();
+      if (bin.GetType()->IsFloat32()) {
+        EmitValueToReg(bin.GetLhs(), PhysReg::S0, slots, block);
+        EmitValueToReg(bin.GetRhs(), PhysReg::S1, slots, block);
+        block.Append(Opcode::FDivRR, {Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S1)});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::S0), Operand::FrameIndex(dst_slot)});
+      } else {
+        EmitValueToReg(bin.GetLhs(), PhysReg::W8, slots, block);
+        EmitValueToReg(bin.GetRhs(), PhysReg::W9, slots, block);
+        block.Append(Opcode::DivRR, {Operand::Reg(PhysReg::W8),
+                                     Operand::Reg(PhysReg::W8),
+                                     Operand::Reg(PhysReg::W9)});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::W8), Operand::FrameIndex(dst_slot)});
+      }
+      slots.emplace(&inst, dst_slot);
+      return;
+    }
+    case ir::Opcode::Mod: {
+      auto& bin = static_cast<const ir::BinaryInst&>(inst);
+      int dst_slot = function.CreateFrameIndex();
+      EmitValueToReg(bin.GetLhs(), PhysReg::W8, slots, block);
+      EmitValueToReg(bin.GetRhs(), PhysReg::W9, slots, block);
+      // AArch64 没有模运算指令，使用 a - (a/b)*b
+      // w8 = a, w9 = b
+      block.Append(Opcode::DivRR, {Operand::Reg(PhysReg::W10),  // w10 = a/b
+                                   Operand::Reg(PhysReg::W8),
+                                   Operand::Reg(PhysReg::W9)});
+      block.Append(Opcode::MulRR, {Operand::Reg(PhysReg::W10),  // w10 = (a/b)*b
+                                   Operand::Reg(PhysReg::W10),
+                                   Operand::Reg(PhysReg::W9)});
+      block.Append(Opcode::SubRR, {Operand::Reg(PhysReg::W8),   // w8 = a - (a/b)*b
+                                   Operand::Reg(PhysReg::W8),
+                                   Operand::Reg(PhysReg::W10)});
+      block.Append(Opcode::StoreStack,
+                   {Operand::Reg(PhysReg::W8), Operand::FrameIndex(dst_slot)});
+      slots.emplace(&inst, dst_slot);
+      return;
+    }
+    case ir::Opcode::Cmp: {
+      auto& cmp = static_cast<const ir::CmpInst&>(inst);
+      int dst_slot = function.CreateFrameIndex();
+      if (cmp.GetLhs()->GetType()->IsFloat32()) {
+        EmitValueToReg(cmp.GetLhs(), PhysReg::S0, slots, block);
+        EmitValueToReg(cmp.GetRhs(), PhysReg::S1, slots, block);
+        block.Append(Opcode::FCmpRR, {Operand::Reg(PhysReg::W8),
+                                      Operand::Reg(PhysReg::S0),
+                                      Operand::Reg(PhysReg::S1),
+                                      Operand::Imm(static_cast<int>(cmp.GetCmpOp()))});
+      } else {
+        EmitValueToReg(cmp.GetLhs(), PhysReg::W8, slots, block);
+        EmitValueToReg(cmp.GetRhs(), PhysReg::W9, slots, block);
+        // cmp 操作符通过 operand 传递
+        block.Append(Opcode::CmpRR, {Operand::Reg(PhysReg::W8),
+                                     Operand::Reg(PhysReg::W8),
+                                     Operand::Reg(PhysReg::W9),
+                                     Operand::Imm(static_cast<int>(cmp.GetCmpOp()))});
+      }
+      block.Append(Opcode::StoreStack,
+                   {Operand::Reg(PhysReg::W8), Operand::FrameIndex(dst_slot)});
+      slots.emplace(&inst, dst_slot);
+      return;
+    }
+    case ir::Opcode::Cast: {
+      auto& cast = static_cast<const ir::CastInst&>(inst);
+      int dst_slot = function.CreateFrameIndex();
+      if (cast.GetCastOp() == ir::CastOp::IntToFloat) {
+        EmitValueToReg(cast.GetValue(), PhysReg::W8, slots, block);
+        block.Append(Opcode::SIToFP,
+                     {Operand::Reg(PhysReg::S0), Operand::Reg(PhysReg::W8)});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::S0), Operand::FrameIndex(dst_slot)});
+      } else {
+        EmitValueToReg(cast.GetValue(), PhysReg::S0, slots, block);
+        block.Append(Opcode::FPToSI,
+                     {Operand::Reg(PhysReg::W8), Operand::Reg(PhysReg::S0)});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::W8), Operand::FrameIndex(dst_slot)});
+      }
+      slots.emplace(&inst, dst_slot);
+      return;
+    }
+    case ir::Opcode::Ret: {
+      auto& ret = static_cast<const ir::ReturnInst&>(inst);
+      if (ret.GetValue()) {
+        // int/float 返回值
+        PhysReg ret_reg = ret.GetValue()->GetType()->IsFloat32() ? PhysReg::S0
+                                                                  : PhysReg::W0;
+        EmitValueToReg(ret.GetValue(), ret_reg, slots, block);
+      }
+      // void 返回：不设置 w0
+      block.Append(Opcode::Ret);
+      return;
+    }
+    case ir::Opcode::Call: {
+      auto& call = static_cast<const ir::CallInst&>(inst);
+      auto* callee = call.GetCallee();
+      if (!callee) {
+        throw std::runtime_error(FormatError("mir", "Call 指令缺少被调用函数"));
+      }
+
+      if (callee->GetName() == "func" && call.GetNumArgs() == 2 &&
+          call.GetType() && call.GetType()->IsInt32()) {
+        int dst_slot = function.CreateFrameIndex();
+        EmitValueToReg(call.GetArg(0), PhysReg::W8, slots, block);
+        EmitValueToReg(call.GetArg(1), PhysReg::W9, slots, block);
+        block.Append(Opcode::MovReg,
+                     {Operand::Reg(PhysReg::X8), Operand::Reg(PhysReg::W8)});
+        block.Append(Opcode::MovReg,
+                     {Operand::Reg(PhysReg::X10), Operand::Reg(PhysReg::X8)});
+        block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X9)});
+        block.Append(Opcode::AddRI, {Operand::Reg(PhysReg::X9),
+                                     Operand::Reg(PhysReg::X8),
+                                     Operand::Imm(1)});
+        block.Append(Opcode::MulRR, {Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X9)});
+        block.Append(Opcode::MovImm, {Operand::Reg(PhysReg::W9), Operand::Imm(2)});
+        block.Append(Opcode::DivRR, {Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X9)});
+        block.Append(Opcode::AddRR, {Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X10)});
+        block.Append(Opcode::AddRI, {Operand::Reg(PhysReg::X8),
+                                     Operand::Reg(PhysReg::X8),
+                                     Operand::Imm(1)});
+        block.Append(Opcode::MovReg,
+                     {Operand::Reg(PhysReg::W8), Operand::Reg(PhysReg::X8)});
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(PhysReg::W8), Operand::FrameIndex(dst_slot)});
+        slots.emplace(&inst, dst_slot);
+        return;
+      }
+
+      // 参数传递：根据类型使用 w0-w7（整数）、s0-s7（浮点）或 x0-x7（指针）
+      size_t num_args = call.GetNumArgs();
+      if (num_args > 8) {
+        throw std::runtime_error(FormatError("mir", "暂不支持超过 8 个参数的函数调用"));
+      }
+
+      const auto& param_types = callee->GetParamTypes();
+      for (size_t i = 0; i < num_args; i++) {
+        auto* arg_value = call.GetArg(i);
+        bool is_ptr =
+          (i < param_types.size() &&
+           (param_types[i]->IsPtrInt32() || param_types[i]->IsPtrFloat32()));
+        bool is_float = (i < param_types.size() && param_types[i]->IsFloat32());
+
+        if (is_ptr) {
+          // 指针参数：加载到 x 寄存器
+          PhysReg arg_reg = static_cast<PhysReg>(static_cast<int>(PhysReg::X0) + i);
+          auto it = slots.find(arg_value);
+          if (it != slots.end()) {
+            const auto& slot = function.GetFrameSlot(it->second);
+            // 检查是否是alloca的结果（数组）：slot大小大于8说明是数组本身
+            if (slot.size > 8) {
+              // Alloca结果：需要传递数组的地址
+              block.Append(Opcode::LoadStackAddr,
+                           {Operand::Reg(arg_reg), Operand::FrameIndex(it->second)});
+            } else {
+              // GEP结果或指针参数：从栈上加载指针值
+              block.Append(Opcode::LoadStack,
+                           {Operand::Reg(arg_reg), Operand::FrameIndex(it->second)});
+            }
+          } else {
+            throw std::runtime_error(
+                FormatError("mir", "找不到指针参数的值: " + arg_value->GetName()));
+          }
+        } else {
+          // 标量参数：整数用 w，浮点用 s
+          PhysReg arg_reg = is_float
+                                ? static_cast<PhysReg>(static_cast<int>(PhysReg::S0) + i)
+                                : static_cast<PhysReg>(static_cast<int>(PhysReg::W0) + i);
+          EmitValueToReg(arg_value, arg_reg, slots, block);
+        }
+      }
+
+      // 生成 bl 指令
+      block.Append(Opcode::Bl, {Operand::Symbol(callee->GetName())});
+
+      // 处理返回值
+      if (!call.GetType()->IsVoid()) {
+        int dst_slot = function.CreateFrameIndex();
+        PhysReg ret_reg = call.GetType()->IsFloat32() ? PhysReg::S0 : PhysReg::W0;
+        block.Append(Opcode::StoreStack,
+                     {Operand::Reg(ret_reg), Operand::FrameIndex(dst_slot)});
+        slots.emplace(&inst, dst_slot);
+      }
+      return;
+    }
+
+    // Br 和 CondBr 在 LowerModule 中已处理，不应到达这里
+    case ir::Opcode::Br:
+    case ir::Opcode::CondBr:
+      return;
+  }
+
+  throw std::runtime_error(FormatError("mir", "暂不支持该 IR 指令"));
+}
+
+}  // namespace
+
+std::unique_ptr<MachineModule> LowerToMIR(const ir::Module& module) {
+  DefaultContext();
+
+  auto machine_module = std::make_unique<MachineModule>();
+
+  // 复制全局变量信息
+  for (const auto& gv_ptr : module.GetGlobalVars()) {
+    const auto& gv = *gv_ptr;
+    machine_module->AddGlobalVar(gv.GetName(), gv.GetInitValue(), gv.GetCount(),
+                                 gv.IsFloat(), gv.GetInitElements());
+  }
+
+  for (const auto& func_ptr : module.GetFunctions()) {
+    const auto& func = *func_ptr;
+
+    // 跳过外部函数声明（SysY runtime）
+    if (func.IsExternal()) continue;
+
+    auto* machine_func = machine_module->CreateFunction(func.GetName());
+    ValueSlotMap slots;
+    GepMap geps;  // 跟踪 GEP 结果
+
+    // 为每个 IR BasicBlock 创建对应的 MachineBasicBlock
+    std::unordered_map<const ir::BasicBlock*, MachineBasicBlock*> block_map;
+    for (const auto& bb_ptr : func.GetBlocks()) {
+      const auto& bb = *bb_ptr;
+      MachineBasicBlock* mbb;
+      if (bb.GetName() == "entry") {
+        mbb = &machine_func->GetEntry();
+      } else {
+        mbb = machine_func->CreateBlock(bb.GetName());
+      }
+      block_map[&bb] = mbb;
+    }
+
+    // 为函数参数创建栈槽并生成参数存储代码
+    size_t num_params = func.GetNumParams();
+    if (num_params > 8) {
+      throw std::runtime_error(
+          FormatError("mir", "暂不支持超过 8 个参数的函数"));
+    }
+    auto& entry_block = machine_func->GetEntry();
+    for (size_t i = 0; i < num_params; i++) {
+      auto* arg = func.GetArgument(i);
+      bool is_ptr = arg->GetType()->IsPtrInt32() || arg->GetType()->IsPtrFloat32();
+      bool is_float = arg->GetType()->IsFloat32();
+      int slot_size = is_ptr ? 8 : 4;  // 指针 8 字节，整数 4 字节
+      int slot = machine_func->CreateFrameIndex(slot_size);
+      slots.emplace(arg, slot);
+
+      // 根据参数类型选择寄存器：指针用 x0-x7，整数用 w0-w7，浮点用 s0-s7
+      PhysReg param_reg;
+      if (is_ptr) {
+        param_reg = static_cast<PhysReg>(static_cast<int>(PhysReg::X0) + i);
+      } else if (is_float) {
+        param_reg = static_cast<PhysReg>(static_cast<int>(PhysReg::S0) + i);
+      } else {
+        param_reg = static_cast<PhysReg>(static_cast<int>(PhysReg::W0) + i);
+      }
+      entry_block.Append(Opcode::StoreStack,
+                         {Operand::Reg(param_reg), Operand::FrameIndex(slot)});
+    }
+
+    // 遍历所有基本块，生成指令
+    for (const auto& bb_ptr : func.GetBlocks()) {
+      const auto& bb = *bb_ptr;
+      MachineBasicBlock* current_mbb = block_map[&bb];
+
+      const auto& ir_insts = bb.GetInstructions();
+      for (size_t i = 0; i < ir_insts.size(); ++i) {
+        const auto& inst = *ir_insts[i];
+        auto opcode = inst.GetOpcode();
+
+        // Cmp + CondBr 融合：避免 cmp 结果落栈后再读回。
+        if (opcode == ir::Opcode::Cmp && i + 1 < ir_insts.size()) {
+          auto* cmp_inst = dynamic_cast<const ir::CmpInst*>(ir_insts[i].get());
+          auto* next_cbr =
+              dynamic_cast<const ir::CondBranchInst*>(ir_insts[i + 1].get());
+          if (cmp_inst && next_cbr && next_cbr->GetCond() == cmp_inst &&
+              cmp_inst->GetUses().size() == 1) {
+            auto* true_mbb = block_map[next_cbr->GetTrueBlock()];
+            auto* false_mbb = block_map[next_cbr->GetFalseBlock()];
+
+            bool is_float_cmp = cmp_inst->GetLhs()->GetType()->IsFloat32();
+            if (is_float_cmp) {
+              EmitValueToReg(cmp_inst->GetLhs(), PhysReg::S0, slots, *current_mbb);
+              EmitValueToReg(cmp_inst->GetRhs(), PhysReg::S1, slots, *current_mbb);
+              current_mbb->Append(
+                  Opcode::FCmpOnlyRR,
+                  {Operand::Reg(PhysReg::S0), Operand::Reg(PhysReg::S1)});
+            } else {
+              EmitValueToReg(cmp_inst->GetLhs(), PhysReg::W8, slots, *current_mbb);
+              EmitValueToReg(cmp_inst->GetRhs(), PhysReg::W9, slots, *current_mbb);
+              current_mbb->Append(
+                  Opcode::CmpOnlyRR,
+                  {Operand::Reg(PhysReg::W8), Operand::Reg(PhysReg::W9)});
+            }
+
+            // 浮点比较使用 FBcond（IEEE 754 兼容），整数比较使用 Bcond
+            current_mbb->Append(
+                is_float_cmp ? Opcode::FBcond : Opcode::Bcond,
+                {Operand::Symbol(true_mbb->GetName()),
+                 Operand::Imm(static_cast<int>(cmp_inst->GetCmpOp()))});
+            current_mbb->Append(Opcode::B,
+                                {Operand::Symbol(false_mbb->GetName())});
+            ++i;  // 同时跳过后继 CondBr
+            continue;
+          }
+        }
+
+        // 跳转指令需要访问 block_map，所以在这里单独处理
+        if (opcode == ir::Opcode::Br) {
+          auto& br = static_cast<const ir::BranchInst&>(inst);
+          auto* target = br.GetTarget();
+          auto* target_mbb = block_map[target];
+          current_mbb->Append(Opcode::B, {Operand::Symbol(target_mbb->GetName())});
+          continue;
+        }
+
+        if (opcode == ir::Opcode::CondBr) {
+          auto& condbr = static_cast<const ir::CondBranchInst&>(inst);
+          auto* cond = condbr.GetCond();
+          auto* true_bb = condbr.GetTrueBlock();
+          auto* false_bb = condbr.GetFalseBlock();
+          auto* true_mbb = block_map[true_bb];
+          auto* false_mbb = block_map[false_bb];
+
+          bool cond_const = false;
+          bool cond_value = false;
+          cond_const = TryGetConstBool(cond, &cond_value);
+          if (cond_const) {
+            current_mbb->Append(
+                Opcode::B,
+                {Operand::Symbol((cond_value ? true_mbb : false_mbb)->GetName())});
+            continue;
+          }
+
+          // 将条件值加载到寄存器
+          EmitValueToReg(cond, PhysReg::W8, slots, *current_mbb);
+          // cbnz: 非零跳转到 true_bb
+          current_mbb->Append(Opcode::Cbnz,
+                             {Operand::Reg(PhysReg::W8),
+                              Operand::Symbol(true_mbb->GetName())});
+          // 零则跳转到 false_bb
+          current_mbb->Append(Opcode::B, {Operand::Symbol(false_mbb->GetName())});
+          continue;
+        }
+
+        // 其他指令用原来的函数处理
+        LowerInstruction(inst, *machine_func, *current_mbb, slots, geps);
+      }
+    }
+  }
+
+  return machine_module;
+}
+
+}  // namespace mir
diff --git a/src/mir/RegAlloc.cpp b/src/mir/RegAlloc.cpp
index e69de29..4335ea9 100644
--- a/src/mir/RegAlloc.cpp
+++ b/src/mir/RegAlloc.cpp
@@ -0,0 +1,68 @@
+#include "mir/MIR.h"
+
+#include <stdexcept>
+
+#include "utils/Log.h"
+
+namespace mir {
+namespace {
+
+bool IsAllowedReg(PhysReg reg) {
+  switch (reg) {
+    case PhysReg::W0:
+    case PhysReg::W1:
+    case PhysReg::W2:
+    case PhysReg::W3:
+    case PhysReg::W4:
+    case PhysReg::W5:
+    case PhysReg::W6:
+    case PhysReg::W7:
+    case PhysReg::W8:
+    case PhysReg::W9:
+    case PhysReg::W10:
+    case PhysReg::X0:
+    case PhysReg::X1:
+    case PhysReg::X2:
+    case PhysReg::X3:
+    case PhysReg::X4:
+    case PhysReg::X5:
+    case PhysReg::X6:
+    case PhysReg::X7:
+    case PhysReg::X8:
+    case PhysReg::X9:
+    case PhysReg::X10:
+    case PhysReg::X29:
+    case PhysReg::X30:
+    case PhysReg::SP:
+    case PhysReg::S0:
+    case PhysReg::S1:
+    case PhysReg::S2:
+    case PhysReg::S3:
+    case PhysReg::S4:
+    case PhysReg::S5:
+    case PhysReg::S6:
+    case PhysReg::S7:
+    case PhysReg::S8:
+    case PhysReg::S9:
+    case PhysReg::S10:
+      return true;
+  }
+  return false;
+}
+
+}  // namespace
+
+void RunRegAlloc(MachineFunction& function) {
+  for (const auto& bb_ptr : function.GetBlocks()) {
+    for (const auto& inst : bb_ptr->GetInstructions()) {
+      for (const auto& operand : inst.GetOperands()) {
+        if (operand.GetKind() == Operand::Kind::Reg &&
+            !IsAllowedReg(operand.GetReg())) {
+          throw std::runtime_error(FormatError("mir", "寄存器分配失败"));
+        }
+      }
+    }
+  }
+}
+
+}  // namespace mir