Merge pull request #17 from mrLSD/feat/register-number

Feat: extend SemanticStack with registers

Author: mrLSD

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "semantic-analyzer"
-version = "0.2.6"
+version = "0.3.0"
 authors = ["Evgeny Ukhanov <[email protected]>"]
 description = "Semantic analyzer library for compilers written in Rust for semantic analysis of programming languages AST"
 keywords = ["compiler", "semantic-analisis", "semantic-alalyzer", "compiler-design", "semantic"]

README.md

@@ -11,56 +11,56 @@
 Semantic analyzer is an open source semantic analyzer for programming languages 
 that makes it easy to build your own efficient compilers.
 
-## What is the library for and what tasks does it solve
+## 🌀 What is the library for and what tasks does it solve
 
 Creating a compilers for a programming language is process that involves several key 
 stages. Most commonly it is:
 
-- **Lexical Analysis (Lexer)**: This stage involves breaking down the input stream 
+▶️ **Lexical Analysis (Lexer)**: This stage involves breaking down the input stream 
 of characters into a series of tokens. Tokens are the atomic elements of the programming language, such as identifiers, keywords, operators, etc.
 
-- **Syntax Analysis (Parsing)**: At this stage, the tokens obtained in the previous 
+▶️ **Syntax Analysis (Parsing)**: At this stage, the tokens obtained in the previous 
 stage are grouped according to the grammar rules of the programming language. The result 
 of this process is an **Abstract Syntax Tree (AST)**, which represents a hierarchical structure of the code.
 
-- **Semantic Analysis**: This stage involves checking the semantic correctness of the code. This can include 
+⏩ **Semantic Analysis**: This stage involves checking the semantic correctness of the code. This can include 
 type checking, scope verification of variables, etc.
 
-- **Intermediate Code Optimization**: At this stage, the compiler tries to improve the intermediate representation of the code to make it more efficient. 
+▶️ **Intermediate Code Optimization**: At this stage, the compiler tries to improve the intermediate representation of the code to make it more efficient. 
 This can include dead code elimination, expression simplification, etc.
 
-- **Code Generation**: This is the final stage where the compiler transforms the optimized intermediate representation (IR) into 
+▶️ **Code Generation**: This is the final stage where the compiler transforms the optimized intermediate representation (IR) into 
 machine code specific to the target architecture.
 
 This library represent **Semantic Analysis** stage.
 
-### Features
+### 🌻 Features
 
-- **Name Binding and Scope Checking**: The analyzer verifies that all variables, constants, functions are declared before they're used, 
+✅ **Name Binding and Scope Checking**: The analyzer verifies that all variables, constants, functions are declared before they're used, 
 and that they're used within their scope. It also checks for name collisions, where variables, constants, functions, types in the same scope have the same name.
 
-- **Checking Function Calls**: The analyzer verifies that functions are called with the number of parameters and that the type of 
+✅ **Checking Function Calls**: The analyzer verifies that functions are called with the number of parameters and that the type of 
 arguments matches the type expected by the function.
 
-- **Scope Rules**: Checks that variables, functions, constants, types are used within their scope, and available in the visibility scope.
+✅ **Scope Rules**: Checks that variables, functions, constants, types are used within their scope, and available in the visibility scope.
 
-- **Type Checking**: The analyzer checks that operations are performed on compatible types for expressions, functions, constant, bindings.
+✅ **Type Checking**: The analyzer checks that operations are performed on compatible types for expressions, functions, constant, bindings.
 For operations in expressions. It is the process of verifying that the types of expressions are consistent with their usage in the context.
 
-- **Flow Control Checking**: The analyzer checks that the control flow statements (if-else, loop, return, break, continue) are used correctly. 
+✅ **Flow Control Checking**: The analyzer checks that the control flow statements (if-else, loop, return, break, continue) are used correctly. 
 Supported condition expressions and condition expression correctness check.
 
-- **Building the Symbol Table**: For analyzing used the symbol table as data structure used by the semantic analyzer to keep track of 
+✅ **Building the Symbol Table**: For analyzing used the symbol table as data structure used by the semantic analyzer to keep track of 
 symbols (variables, functions, constants) in the source code. Each entry in the symbol table contains the symbol's name, type, and scope related for block state, and other relevant information.
 
-### Semantic State Tree
+### 🌳 Semantic State Tree
 
 The result of executing and passing stages of the semantic analyzer is: **Semantic State Tree**.
 
 This can be used for Intermediate Code Generation, for further passes
 semantic tree optimizations, linting, backend codegen (like LLVM) to target machine.
 
-#### Structure of Semantic State Tree 
+#### 🌲 Structure of Semantic State Tree 
 
 - **blocks state** and related block state child branches. It's a basic
 entity for scopes: variables, blocks (function, if, loop). 
@@ -87,7 +87,7 @@ However, parent elements cannot access child elements, which effectively limits
 
 All of that source data, that can be used for Intermediate Representation for next optimizations and compilers codegen.
 
-### Subset of programming languages
+### 🧺 Subset of programming languages
 
 The input parameter for the analyzer is a predefined
 AST (abstract syntax tree). As a library for building AST and the only dependency
@@ -104,4 +104,12 @@ analysis and source code parsing, it is recommended to use: [nom is a parser com
 
 AST displays the **Turing complete** programming language and contains all the necessary elements for this.
 
+## 🛋️ Examples
+
+- 🔎 There is the example implementation separate project [💾 Toy Codegen](https://github.com/mrLSD/toy-codegen).
+The project uses the `SemanticStack` results and converts them into **Code Generation** logic. Which clearly shows the 
+possibilities of using the results of the `semantic-analyzer-rs` `SemanticStackContext` results. LLVM is used as a 
+backend, [inkwell](https://github.com/TheDan64/inkwell) as a library for LLVM codegen, and compiled into an executable 
+program. The source of data is the AST structure itself.
+
 ## MIT [LICENSE](LICENSE)

src/semantic.rs

@@ -533,18 +533,26 @@ impl State {
             params.push(expr_result);
         }
 
+        // Result of function call is stored to register
+        body_state.borrow_mut().inc_register();
+        let last_register_number = body_state.borrow().last_register_number;
         // Store always result to register even for void result
-        body_state.borrow_mut().context.call(func_data, params);
+        body_state
+            .borrow_mut()
+            .context
+            .call(func_data, params, last_register_number);
         Some(fn_type)
     }
 
     /// # condition-expression
-    /// Analyse condition operations.    
+    /// Analyse condition operations.
+    /// ## Return
+    /// Return result register of `condition-expression` calculation.
     pub fn condition_expression(
         &mut self,
         data: &ast::ExpressionLogicCondition<'_>,
         function_body_state: &Rc<RefCell<BlockState>>,
-    ) {
+    ) -> u64 {
         // Analyse left expression of left condition
         let left_expr = &data.left.left;
         let left_res = self.expression(left_expr, function_body_state);
@@ -553,12 +561,15 @@ impl State {
         let right_expr = &data.left.right;
         let right_res = self.expression(right_expr, function_body_state);
 
-        let (Some(left_res), Some(right_res)) = (left_res, right_res) else {
-            return;
+        // If some of the `left` or `right` expression is empty just return with error in the state
+        let (Some(left_res), Some(right_res)) = (left_res.clone(), right_res.clone()) else {
+            self.add_error(error::StateErrorResult::new(
+                error::StateErrorKind::ConditionIsEmpty,
+                format!("left={left_res:?}, right={right_res:?}"),
+                data.left.left.location(),
+            ));
+            return function_body_state.borrow().last_register_number;
         };
-        // Unwrap result only after analysing
-        // let left_res = left_res?;
-        // let right_res = right_res?;
 
         // Currently strict type comparison
         if left_res.expr_type != right_res.expr_type {
@@ -567,7 +578,7 @@ impl State {
                 left_res.expr_type.to_string(),
                 data.left.left.location(),
             ));
-            return;
+            return function_body_state.borrow().last_register_number;
         }
         match left_res.expr_type {
             Type::Primitive(_) => (),
@@ -577,29 +588,46 @@ impl State {
                     left_res.expr_type.to_string(),
                     data.left.left.location(),
                 ));
-                return;
+                return function_body_state.borrow().last_register_number;
             }
         }
 
+        // Increment register
+        function_body_state.borrow_mut().inc_register();
+
+        let register_number = function_body_state.borrow_mut().last_register_number;
         // Codegen for left condition and set result to register
         function_body_state
             .borrow_mut()
             .context
-            .condition_expression(left_res, right_res, data.left.condition.clone().into());
+            .condition_expression(
+                left_res,
+                right_res,
+                data.left.condition.clone().into(),
+                register_number,
+            );
 
         // Analyze right condition
         if let Some(right) = &data.right {
+            let left_register_result = function_body_state.borrow_mut().last_register_number;
             // Analyse recursively right part of condition
-            self.condition_expression(&right.1, function_body_state);
+            let right_register_result = self.condition_expression(&right.1, function_body_state);
 
+            // Increment register
+            function_body_state.borrow_mut().inc_register();
+
+            let register_number = function_body_state.borrow_mut().last_register_number;
             // Stategen for logical condition for: left [LOGIC-OP] right
             // The result generated from registers, and stored to
             // new register
-            function_body_state
-                .borrow_mut()
-                .context
-                .logic_condition(right.0.clone().into());
+            function_body_state.borrow_mut().context.logic_condition(
+                right.0.clone().into(),
+                left_register_result,
+                right_register_result,
+                register_number,
+            );
         }
+        function_body_state.borrow_mut().last_register_number
     }
 
     /// # If-condition body
@@ -793,18 +821,20 @@ impl State {
             // If condition contains logic condition expression
             ast::IfCondition::Logic(expr_logic) => {
                 // Analyse if-condition logic
-                self.condition_expression(expr_logic, if_body_state);
+                let result_register = self.condition_expression(expr_logic, if_body_state);
                 // State for if-condition-logic with if-body start
                 if is_else {
-                    if_body_state
-                        .borrow_mut()
-                        .context
-                        .if_condition_logic(label_if_begin.clone(), label_if_else.clone());
+                    if_body_state.borrow_mut().context.if_condition_logic(
+                        label_if_begin.clone(),
+                        label_if_else.clone(),
+                        result_register,
+                    );
                 } else {
-                    if_body_state
-                        .borrow_mut()
-                        .context
-                        .if_condition_logic(label_if_begin.clone(), label_if_end.clone());
+                    if_body_state.borrow_mut().context.if_condition_logic(
+                        label_if_begin.clone(),
+                        label_if_end.clone(),
+                        result_register,
+                    );
                 }
             }
         }
@@ -1169,18 +1199,21 @@ impl State {
             ast::ExpressionValue::ValueName(value) => {
                 // Get value from block state
                 let value_from_state = body_state.borrow_mut().get_value_name(&value.name().into());
+                // Register contains result
+                body_state.borrow_mut().inc_register();
+                let last_register_number = body_state.borrow().last_register_number;
                 // First check value in body state
                 let ty = if let Some(val) = value_from_state {
                     body_state
                         .borrow_mut()
                         .context
-                        .expression_value(val.clone());
+                        .expression_value(val.clone(), last_register_number);
                     val.inner_type
                 } else if let Some(const_val) = self.global.constants.get(&value.name().into()) {
                     body_state
                         .borrow_mut()
                         .context
-                        .expression_const(const_val.clone());
+                        .expression_const(const_val.clone(), last_register_number);
                     const_val.constant_type.clone()
                 } else {
                     // If value doesn't exist in State or as Constant
@@ -1192,7 +1225,6 @@ impl State {
                     return None;
                 };
                 // Return result as register
-                body_state.borrow_mut().inc_register();
                 ExpressionResult {
                     expr_type: ty,
                     expr_value: ExpressionResultValue::Register(
@@ -1274,10 +1306,14 @@ impl State {
                     })?
                     .clone();
 
-                body_state
-                    .borrow_mut()
-                    .context
-                    .expression_struct_value(val.clone(), attributes.clone().attr_index);
+                // Register contains result
+                body_state.borrow_mut().inc_register();
+                let last_register_number = body_state.borrow().last_register_number;
+                body_state.borrow_mut().context.expression_struct_value(
+                    val.clone(),
+                    attributes.clone().attr_index,
+                    last_register_number,
+                );
 
                 body_state.borrow_mut().inc_register();
                 ExpressionResult {
@@ -1303,14 +1339,17 @@ impl State {
                 // Do not fetch other expression flow if type is wrong
                 return None;
             }
+            // Expression operation is set to register
+            body_state.borrow_mut().inc_register();
+            let last_register_number = body_state.borrow().last_register_number;
             // Call expression operation for: OP(left_value, right_value)
             body_state.borrow_mut().context.expression_operation(
                 op.clone().into(),
                 left_value.clone(),
                 right_value.clone(),
+                last_register_number,
             );
             // Expression result value  for Operations is always should be "register"
-            body_state.borrow_mut().inc_register();
             ExpressionResult {
                 expr_type: right_value.expr_type,
                 expr_value: ExpressionResultValue::Register(

src/types/error.rs

@@ -26,6 +26,7 @@ pub enum StateErrorKind {
     TypeNotFound,
     WrongReturnType,
     ConditionExpressionWrongType,
+    ConditionIsEmpty,
     ConditionExpressionNotSupported,
     ForbiddenCodeAfterReturnDeprecated,
     ForbiddenCodeAfterContinueDeprecated,