feat(sem)增添常量绑定

include/sem/Sema.h

@@ -34,6 +34,14 @@ public:
         return it == var_uses_.end() ? nullptr : it->second;
     }
 
+    void BindConstUse(SysYParser::LValContext* use, SysYParser::ConstDefContext* decl) {
+        const_uses_[use] = decl;
+    }
+    SysYParser::ConstDefContext* ResolveConstUse(const SysYParser::LValContext* use) const {
+        auto it = const_uses_.find(use);
+        return it == const_uses_.end() ? nullptr : it->second;
+    }
+
     // ----- 表达式类型信息存储 -----
     void SetExprType(antlr4::ParserRuleContext* node, const ExprInfo& info) {
         ExprInfo copy = info;
@@ -76,6 +84,8 @@ private:
     
     // 隐式转换列表
     std::vector<ConversionInfo> conversions_;
+
+    std::unordered_map<const SysYParser::LValContext*, SysYParser::ConstDefContext*> const_uses_;
 };
 
 // 目前仅检查：

include/sem/SymbolTable.h

@@ -43,6 +43,8 @@ struct Symbol {
 
     // 关联的语法树节点（用于报错位置或进一步分析）
     SysYParser::VarDefContext* var_def_ctx = nullptr;
+    SysYParser::ConstDefContext* const_def_ctx = nullptr;
+    SysYParser::FuncFParamContext* param_def_ctx = nullptr;
     SysYParser::FuncDefContext* func_def_ctx = nullptr;
 };
 

src/irgen/IRGenExp.cpp

@@ -84,9 +84,11 @@ std::any IRGenImpl::visitLVal(SysYParser::LValContext* ctx) {
   // 从语义分析获取变量定义
   auto* decl = sema_.ResolveVarUse(ctx);
   if (!decl) {
-    throw std::runtime_error(
+    auto* const_def = sema_.ResolveConstUse(ctx);
+    if (!const_def) {
         FormatError("irgen",
-                    "变量使用缺少语义绑定: " + varName));
+                    "使用缺少语义绑定: " + varName);
+    }
   }
   
   auto it = storage_map_.find(decl);

src/sem/Sema.cpp

@@ -298,6 +298,9 @@ public:
         sym.scope_level = table_.currentScopeLevel();
         sym.is_initialized = true;
         sym.var_def_ctx = nullptr;
+        sym.const_def_ctx = ctx;
+        sym.const_def_ctx = ctx;
+        std::cout << "保存常量定义上下文: " << name << ", ctx: " << ctx << std::endl;
         // 存储常量值（仅对非数组有效）
         if (!is_array && !init_values.empty()) {
             if (base_type->IsInt32() && init_values[0].kind == SymbolTable::ConstValue::INT) {
@@ -1056,9 +1059,17 @@ private:
 
         if (sym->kind == SymbolKind::Variable && sym->var_def_ctx) {
             sema_.BindVarUse(ctx, sym->var_def_ctx);
+            std::cout << "绑定变量: " << name << " -> VarDefContext" << std::endl;
         }
-        std::cout << "CheckLValue 绑定变量: " << name << std::endl;
-        
+        else if (sym->kind == SymbolKind::Constant && sym->const_def_ctx) {
+            sema_.BindConstUse(ctx, sym->const_def_ctx);
+            std::cout << "绑定常量: " << name << " -> ConstDefContext" << std::endl;
+        }
+        std::cout << "CheckLValue 绑定变量: " << name 
+                << ", sym->kind: " << (int)sym->kind 
+                << ", sym->var_def_ctx: " << sym->var_def_ctx
+                << ", sym->const_def_ctx: " << sym->const_def_ctx << std::endl;
+
         bool is_array_access = !ctx->exp().empty();
         bool is_const = (sym->kind == SymbolKind::Constant);