From 43abaa4a46f1648e0c309bd1c2caff64d9f1f4ab Mon Sep 17 00:00:00 2001
From: Sofia <sofia@teascade.net>
Date: Thu, 9 Apr 2026 17:44:22 +0300
Subject: [PATCH] Make expressions return StackValue

---
 src/ast.h       |  8 ++++----
 src/codegen.cpp | 21 ++++++++++++---------
 2 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/src/ast.h b/src/ast.h
index 537b77f..1d64766 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -23,7 +23,7 @@ namespace AST {
 
     class Expression : public Node {
     public:
-        virtual llvm::Value* codegen(codegen::Builder& builder, codegen::Scope& scope) = 0;
+        virtual codegen::StackValue codegen(codegen::Builder& builder, codegen::Scope& scope) = 0;
     };
 
     class Type {
@@ -45,7 +45,7 @@ namespace AST {
         IntLiteralExpression(int value) : m_value{ value } {}
         virtual ~IntLiteralExpression() override = default;
         virtual std::string formatted() override;
-        virtual llvm::Value* codegen(codegen::Builder& builder, codegen::Scope& scope) override;
+        virtual codegen::StackValue codegen(codegen::Builder& builder, codegen::Scope& scope) override;
     };
 
     class ValueReferenceExpression : public Expression {
@@ -55,7 +55,7 @@ namespace AST {
         ValueReferenceExpression(std::string name) : m_name{ name } {}
         virtual ~ValueReferenceExpression() override = default;
         virtual std::string formatted() override;
-        virtual llvm::Value* codegen(codegen::Builder& builder, codegen::Scope& scope) override;
+        virtual codegen::StackValue codegen(codegen::Builder& builder, codegen::Scope& scope) override;
     };
 
     class BinaryOperationExpression : public Expression {
@@ -69,7 +69,7 @@ namespace AST {
         }
         virtual ~BinaryOperationExpression() override = default;
         virtual std::string formatted() override;
-        virtual llvm::Value* codegen(codegen::Builder& builder, codegen::Scope& scope) override;
+        virtual codegen::StackValue codegen(codegen::Builder& builder, codegen::Scope& scope) override;
     };
 
 
diff --git a/src/codegen.cpp b/src/codegen.cpp
index 009ba8e..451ea25 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -13,19 +13,22 @@ namespace codegen {
 }
 
 namespace AST {
-    llvm::Value* IntLiteralExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
+    codegen::StackValue IntLiteralExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
         auto ty = builder.builder->getInt32Ty();
-        return llvm::ConstantInt::get(ty, this->m_value);
+        return codegen::StackValue{ llvm::ConstantInt::get(ty, this->m_value), ty };
     }
 
-    llvm::Value* ValueReferenceExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
+    codegen::StackValue ValueReferenceExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
         auto value = scope.values.find(this->m_name);
         if (value != scope.values.end()) {
             if (scope.is_lvalue) {
-                return value->second.value;
+                return value->second;
             }
             else {
-                return builder.builder->CreateLoad(value->second.ty, value->second.value);
+                return codegen::StackValue{
+                    builder.builder->CreateLoad(value->second.ty, value->second.value),
+                    value->second.ty
+                };
             }
         }
         else {
@@ -33,13 +36,13 @@ namespace AST {
         }
     }
 
-    llvm::Value* BinaryOperationExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
+    codegen::StackValue BinaryOperationExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
         auto lvalued = scope.with_lvalue();
         auto lhs = this->m_lhs->codegen(builder, lvalued);
         auto rhs = this->m_rhs->codegen(builder, scope);
         switch (this->m_binop) {
         case BinOp::Assignment:
-            builder.builder->CreateStore(rhs, lhs, false);
+            builder.builder->CreateStore(rhs.value, lhs.value, false);
             if (scope.is_lvalue) {
                 return lhs;
             }
@@ -58,7 +61,7 @@ namespace AST {
         builder.builder->SetInsertPoint(builder.block);
 
         auto value = this->m_expr->codegen(builder, scope);
-        builder.builder->CreateRet(value);
+        builder.builder->CreateRet(value.value);
     }
 
     void ExpressionStatement::codegen(codegen::Builder& builder, codegen::Scope& scope) {
@@ -79,7 +82,7 @@ namespace AST {
         auto ptr = builder.builder->CreateAlloca(ty);
         if (this->m_expr.has_value()) {
             auto value = this->m_expr->get()->codegen(builder, scope);
-            builder.builder->CreateStore(value, ptr, false);
+            builder.builder->CreateStore(value.value, ptr, false);
         }
 
         scope.values[this->m_name] = codegen::StackValue{ ptr, ty };