fix(sem)修正常量表达式求值问题

include/sem/SymbolTable.h

@@ -95,6 +95,8 @@ class SymbolTable {
         SysYParser::ConstInitValContext* ctx,
         const std::vector<int>& dims,
         std::shared_ptr<ir::Type> base_type) const;
+    
+    int EvaluateConstExpression(SysYParser::ExpContext* ctx) const;
 
   private:
     // 作用域栈：每个元素是一个从名字到符号的映射

src/sem/Sema.cpp

@@ -1348,20 +1348,6 @@ private:
         
         table_.addSymbol(sym);
     }
-    
-    // 在 SemaVisitor 类中添加
-    int EvaluateConstantAddExp(SysYParser::AddExpContext* ctx) {
-        if (!ctx) return 0;
-        // 使用常量求值器
-        // 这里需要访问 ConstEvaluator，但 SemaVisitor 可能没有直接访问
-        // 我们可以直接使用 CheckAddExp 并检查常量
-        ExprInfo info = CheckAddExp(ctx);
-        if (info.is_const && info.is_const_int) {
-            return info.const_int_value;
-        }
-        throw std::runtime_error(FormatError("sema", "常量表达式求值失败"));
-        return 0;
-    }
 
     void CollectFunctionParams(SysYParser::FuncFParamsContext* ctx) {
         if (!ctx) return;
@@ -1400,8 +1386,7 @@ private:
                     }
                     
                     // 求值常量表达式
-                    // 我们需要一个函数来求值常量表达式
-                    int dim = EvaluateConstantAddExp(addExp);
+                    int dim = table_.EvaluateConstExpression(exp_ctx);
                     if (dim <= 0) {
                         throw std::runtime_error(FormatError("sema", "数组维度必须为正整数"));
                     }
@@ -1448,59 +1433,6 @@ private:
         }
     }
     
-    int EvaluateConstExp(SysYParser::ConstExpContext* ctx) {
-        if (!ctx || !ctx->addExp()) return 0;
-        ExprInfo info = CheckAddExp(ctx->addExp());
-        if (info.is_const && info.is_const_int) {
-            return info.const_int_value;
-        }
-        throw std::runtime_error(FormatError("sema", "常量表达式求值失败"));
-        return 0;
-    }
-    
-    struct ConstValue {
-        bool is_int;
-        int int_val;
-        float float_val;
-    };
-    
-    std::vector<ConstValue> EvaluateConstInitVal(SysYParser::ConstInitValContext* ctx,
-                                                  const std::vector<int>& dims,
-                                                  std::shared_ptr<ir::Type> base_type) {
-        std::vector<ConstValue> result;
-        if (!ctx) return result;
-        if (ctx->constExp()) {
-            ExprInfo info = CheckAddExp(ctx->constExp()->addExp());
-            ConstValue val;
-            if (info.type->IsInt32() && info.is_const_int) {
-                val.is_int = true;
-                val.int_val = info.const_int_value;
-                if (base_type->IsFloat()) {
-                    val.is_int = false;
-                    val.float_val = (float)info.const_int_value;
-                }
-            } else if (info.type->IsFloat() && info.is_const) {
-                val.is_int = false;
-                val.float_val = info.const_float_value;
-                if (base_type->IsInt32()) {
-                    val.is_int = true;
-                    val.int_val = (int)info.const_float_value;
-                }
-            } else {
-                val.is_int = base_type->IsInt32();
-                val.int_val = 0;
-                val.float_val = 0.0f;
-            }
-            result.push_back(val);
-        } else {
-            for (auto* init : ctx->constInitVal()) {
-                std::vector<ConstValue> sub_vals = EvaluateConstInitVal(init, dims, base_type);
-                result.insert(result.end(), sub_vals.begin(), sub_vals.end());
-            }
-        }
-        return result;
-    }
-    
     void CheckMainFunction() {
         auto* main_sym = table_.lookup("main");
         if (!main_sym || main_sym->kind != SymbolKind::Function) {

src/sem/SymbolTable.cpp

@@ -656,4 +656,21 @@ std::vector<SymbolTable::ConstValue> SymbolTable::EvaluateConstInitVal(
     }
     
     return flat;
+}
+
+int SymbolTable::EvaluateConstExpression(SysYParser::ExpContext* ctx) const {
+    if (!ctx || !ctx->addExp()) {
+        throw std::runtime_error("常量表达式求值：无效 ExpContext");
+    }
+    ConstValue val = EvaluateAddExp(ctx->addExp());
+    if (val.kind == ConstValue::INT) {
+        return val.int_val;
+    } else {
+        float f = val.float_val;
+        int i = static_cast<int>(f);
+        if (std::abs(f - i) > 1e-6) {
+            throw std::runtime_error("常量表达式求值：浮点常量不能隐式转换为整数");
+        }
+        return i;
+    }
 }