Start adding unary operators

src/ast.cpp

@@ -90,6 +90,21 @@ namespace AST {
         return out.str();
     }
 
+    std::string UnaryExpression::formatted() {
+        std::stringstream out{ "" };
+        switch (this->m_unary) {
+        case types::Unary::AddPostfix:
+            out << this->m_expr->formatted() << "++";
+            break;
+        case types::Unary::AddPrefix:
+            out << "++" << this->m_expr->formatted();
+            break;
+        default:
+            break;
+        }
+        return out.str();
+    }
+
     std::string ExpressionStatement::formatted() {
         std::stringstream out{ "" };
         out << this->m_expr->formatted();

src/ast.h

@@ -322,6 +322,33 @@ namespace AST {
         ) override;
     };
 
+    /// @brief Same as [prefix]value[postfix], e.g. value++ or ++value
+    class UnaryExpression : public Expression {
+    private:
+        std::unique_ptr<Expression> m_expr;
+        types::Unary m_unary;
+    public:
+        UnaryExpression(
+            token::Metadata meta,
+            std::unique_ptr<Expression> expr,
+            types::Unary unary)
+            : Expression{ meta }
+            , m_expr{ std::move(expr) }
+            , m_unary{ unary } {
+        }
+        virtual ~UnaryExpression() override = default;
+        virtual std::string formatted() override;
+        virtual codegen::StackValue codegen(codegen::Builder& builder, codegen::Scope& scope, codegen::StackAllocator& allocator) override;
+        virtual void codegen_alloca(codegen::StackAllocator& allocator) override;
+        virtual std::shared_ptr<types::Type> get_codegen_type(codegen::Scope& scope) override;
+        virtual void typecheck_preprocess(typecheck::Scope& scope) override;
+        virtual typecheck::ExpressionType typecheck(
+            typecheck::State& state,
+            typecheck::Scope& scope,
+            std::optional<std::shared_ptr<types::Type>> expected_ty
+        ) override;
+    };
+
 
     class ReturnStatement : public Statement {
     private:

src/binops.cpp

@@ -101,4 +101,61 @@ namespace types {
         }
         return {};
     }
+
+    std::vector<UnopDefinition> create_unops() {
+        std::vector<UnopDefinition> definitions{};
+
+        auto int_ty = std::shared_ptr<types::Type>{
+            new types::FundamentalType{ false, types::FundamentalTypeKind::Int } };
+        auto char_ty = std::shared_ptr<types::Type>{
+            new types::FundamentalType{ false, types::FundamentalTypeKind::Char } };
+
+        // Integer arithmetic binops
+        for (auto& ty : { int_ty, char_ty }) {
+            definitions.push_back(UnopDefinition{
+                ty, types::Unary::AddPostfix, ty,
+                [](codegen::Builder& builder, std::shared_ptr<Type> ty, llvm::Value* ptr) {
+                    codegen::TypeMap structs {};
+                    auto llvm_ty = ty->codegen(builder, structs);
+                    auto loaded = builder.builder->CreateLoad(llvm_ty, ptr);
+                    auto const_1 = llvm::ConstantInt::get(llvm_ty, 1);
+                    auto result = builder.builder->CreateAdd(loaded, const_1, "add");
+                    builder.builder->CreateStore(result, ptr);
+                    return reinterpret_cast<llvm::Value*>(loaded);
+                }
+                });
+
+            definitions.push_back(UnopDefinition{
+                ty, types::Unary::AddPrefix, ty,
+                [](codegen::Builder& builder, std::shared_ptr<Type> ty, llvm::Value* ptr) {
+                    codegen::TypeMap structs {};
+                    auto llvm_ty = ty->codegen(builder, structs);
+                    auto loaded = builder.builder->CreateLoad(llvm_ty, ptr);
+                    auto const_1 = llvm::ConstantInt::get(llvm_ty, 1);
+                    auto result = builder.builder->CreateAdd(loaded, const_1, "add");
+                    builder.builder->CreateStore(result, ptr);
+                    return result;
+                }
+                });
+        }
+
+        return definitions;
+    }
+
+    std::optional<UnopDefinition> find_unop(
+        std::vector<UnopDefinition>& unops,
+        std::shared_ptr<types::Type> value,
+        Unary op) {
+        for (auto& unop : unops) {
+            if (unop.op != op) {
+                continue;
+            }
+            if (!types_equal(value, unop.value)) {
+                continue;
+            }
+
+            return unop;
+        }
+        return {};
+    }
 }

src/binops.h

@@ -15,6 +15,11 @@ namespace types {
         GreaterThan,
     };
 
+    enum class Unary {
+        AddPostfix,
+        AddPrefix,
+    };
+
     int operator_precedence(BinOp& op);
     std::string format_operator(BinOp& op);
 
@@ -34,6 +39,20 @@ namespace types {
         BinOp op,
         std::shared_ptr<types::Type> rhs);
 
+    struct UnopDefinition {
+        std::shared_ptr<Type> value;
+        Unary op;
+        std::shared_ptr<Type> res;
+        llvm::Value* (*codegen)(codegen::Builder& builder, std::shared_ptr<Type> ty, llvm::Value* value);
+    };
+
+    std::vector<UnopDefinition> create_unops();
+
+    std::optional<UnopDefinition> find_unop(
+        std::vector<UnopDefinition>& unops,
+        std::shared_ptr<types::Type> value,
+        Unary op);
+
 }
 
 #endif

src/codegen.cpp

@@ -11,7 +11,7 @@
 
 namespace codegen {
     Scope Scope::with_lvalue() {
-        return Scope{ this->binops, this->casts, this->structs, this->values, true };
+        return Scope{ this->binops, this->unops, this->casts, this->structs, this->values, true };
     }
 }
 
@@ -449,6 +449,13 @@ namespace AST {
         }
     }
 
+    std::shared_ptr<types::Type> UnaryExpression::get_codegen_type(codegen::Scope& scope) {
+        return this->m_expr->get_codegen_type(scope);
+    }
+
+    codegen::StackValue UnaryExpression::codegen(codegen::Builder&, codegen::Scope&, codegen::StackAllocator&) {
+        throw std::runtime_error("TODO");
+    }
 
     void ReturnStatement::codegen(codegen::Builder& builder, codegen::Scope& scope, codegen::StackAllocator& allocator) {
         if (!builder.block)

src/codegen.h

@@ -20,6 +20,7 @@ namespace codegen {
 
     struct Scope {
         std::vector<types::BinopDefinition>& binops;
+        std::vector<types::UnopDefinition> unops;
         std::vector<types::CastDefinition>& casts;
 
         TypeMap structs;

src/main.cpp

@@ -110,6 +110,7 @@ std::optional<CompileOutput> compile(std::string_view in_filename) {
     // Actual typechecking
     typecheck::State typecheck_state{};
     typecheck_state.binops = types::create_binops();
+    typecheck_state.unops = types::create_unops();
     typecheck_state.casts = types::create_casts();
 
     typecheck::Scope typecheck_scope{};
@@ -134,6 +135,7 @@ std::optional<CompileOutput> compile(std::string_view in_filename) {
 
     codegen::Scope cg_scope{
         .binops = typecheck_state.binops,
+        .unops = typecheck_state.unops,
         .casts = typecheck_state.casts,
         .structs = {},
         .values = {},

src/stack_allocator.cpp

@@ -67,6 +67,10 @@ namespace AST {
         }
     }
 
+    void UnaryExpression::codegen_alloca(codegen::StackAllocator& allocator) {
+        this->m_expr->codegen_alloca(allocator);
+    }
+
     void ReturnStatement::codegen_alloca(codegen::StackAllocator& allocator) {
         this->m_expr->codegen_alloca(allocator);
     }

src/typechecker.cpp

@@ -537,6 +537,38 @@ namespace AST {
         }
     }
 
+    void UnaryExpression::typecheck_preprocess(typecheck::Scope& scope) {
+        this->m_expr->typecheck_preprocess(scope);
+    }
+
+    typecheck::ExpressionType UnaryExpression::typecheck(
+        typecheck::State& state,
+        typecheck::Scope& scope,
+        std::optional<std::shared_ptr<types::Type>> expected_ty
+    ) {
+        auto expr_res = this->m_expr->typecheck(state, scope, expected_ty);
+        if (this->m_unary == types::Unary::AddPostfix || this->m_unary == types::Unary::AddPrefix) {
+            if (!expr_res.lvalue) {
+                state.errors.push_back(CompileError("Value must be a modifyable l-value", this->m_meta));
+            }
+        }
+
+        auto unop = types::find_unop(state.unops, expr_res.type, this->m_unary);
+        if (unop) {
+            auto check_res = check_type(state, expr_res.type, unop->res);
+            this->m_expr = handle_res(std::move(this->m_expr), check_res, state);
+            return {
+                unop->res,
+                false,
+                false,
+            };
+        }
+        else {
+            state.errors.push_back(CompileError("No suitable unary operator found", this->m_meta));
+            return { expr_res.type, false, false };
+        }
+    }
+
     void ReturnStatement::typecheck_preprocess(typecheck::Scope& scope) {
         this->m_expr->typecheck_preprocess(scope);
     }

src/typechecker.h

@@ -17,6 +17,7 @@ namespace typecheck {
 
     struct State {
         std::vector<types::BinopDefinition> binops;
+        std::vector<types::UnopDefinition> unops;
         std::vector<types::CastDefinition> casts;
         std::vector<CompileError> errors;
     };

test.c

@@ -51,5 +51,10 @@ int main() {
     twod_array[0][0] = 50;
     printf("2d array: %d!\n", twod_array[0][0]);
 
+    int counter = 0;
+    printf("counter: %d\n", counter++);
+    printf("counter: %d\n", counter++);
+    printf("counter: %d\n", counter++);
+
     return 0;
 }