实现赋值

include/irgen/IRGen.h

@@ -99,7 +99,7 @@ private:
   ir::IRBuilder builder_;
   std::unordered_map<SysYParser::VarDefContext*, ir::Value*> storage_map_;
   std::unordered_map<SysYParser::VarDefContext*, ArrayInfo> array_info_map_;
-  
+  ir::Value* EvalAssign(SysYParser::StmtContext* ctx);
 };
 
 std::unique_ptr<ir::Module> GenerateIR(SysYParser::CompUnitContext& tree,

src/irgen/IRGenExp.cpp

@@ -452,4 +452,36 @@ std::any IRGenImpl::visitRelExp(SysYParser::RelExpContext* ctx) {
   }
   
   throw std::runtime_error(FormatError("irgen", "未知的关系操作符: " + op));
+}
+
+//赋值
+ir::Value* IRGenImpl::EvalAssign(SysYParser::StmtContext* ctx) {
+  if (!ctx || !ctx->lVal() || !ctx->exp()) {
+    throw std::runtime_error(FormatError("irgen", "非法赋值语句"));
+  }
+  
+  // 计算右值
+  ir::Value* rhs = EvalExpr(*ctx->exp());
+  
+  // 获取左值地址
+  std::string varName = ctx->lVal()->Ident()->getText();
+  
+  // 从语义分析获取变量定义
+  auto* decl = sema_.ResolveVarUse(ctx->lVal());
+  if (!decl) {
+    throw std::runtime_error(
+        FormatError("irgen", "变量使用缺少语义绑定: " + varName));
+  }
+  
+  // 从storage_map_获取存储位置
+  auto it = storage_map_.find(decl);
+  if (it == storage_map_.end()) {
+    throw std::runtime_error(
+        FormatError("irgen", "变量声明缺少存储槽位: " + varName));
+  }
+  
+  // 生成store指令
+  builder_.CreateStore(rhs, it->second);
+  
+  return rhs;
 }