Implement basic IR generator

Signed-off-by: CHatingPython <chatingpython@gmail.com>

furc/include/furc/front/ir_generator.hpp

@@ -0,0 +1,44 @@
+#ifndef FURC_FRONT_IR_GENERATOR_HPP
+#define FURC_FRONT_IR_GENERATOR_HPP
+
+#include "furc/ast/fwd.hpp"
+#include "furc/ast/visitor.hpp"
+#include "furlang/ir/module.hpp"
+
+#include <unordered_map>
+
+namespace furc {
+namespace front {
+
+class ir_generator final : public ast::visitor {
+public:
+    ir_generator()           = default;
+    ~ir_generator() override = default;
+
+    ir_generator(ir_generator&&)                 = default;
+    ir_generator& operator=(ir_generator&&)      = default;
+    ir_generator(const ir_generator&)            = default;
+    ir_generator& operator=(const ir_generator&) = default;
+public:
+    furlang::ir::module&& move_module() { return std::move(m_module); }
+public:
+    void visit_function_definition_node(const ast::function_definition_node& funcDef) override;
+    void visit_return_statement_node(const ast::return_statement_node& returnStmt) override;
+    void visit_string_literal_node(const ast::string_literal_node& node) override;
+    void visit_integer_literal_node(const ast::integer_literal_node& node) override;
+    void visit_var_read_expression_node(const ast::var_read_expression_node& node) override;
+    void visit_unaryop_expression_node(const ast::unaryop_expression_node& node) override;
+    void visit_binop_expression_node(const ast::binop_expression_node& node) override;
+    void visit_var_assign_expression_node(const ast::var_assign_expression_node& node) override;
+private:
+    furlang::ir::module                 m_module;
+    std::shared_ptr<furlang::ir::block> m_currentBlock;
+    std::uint32_t                       m_registerCounter = 0;
+
+    std::unordered_map<std::string_view, std::uint32_t> m_variableMap;
+};
+
+} // namespace front
+} // namespace furc
+
+#endif // FURC_FRONT_IR_GENERATOR_HPP

furc/src/front/ir_generator.cpp

@@ -0,0 +1,96 @@
+#include "furc/front/ir_generator.hpp"
+
+#include "furc/ast/declaration.hpp" // IWYU pragma: keep
+#include "furc/ast/expression.hpp"  // IWYU pragma: keep
+#include "furc/ast/literal.hpp"     // IWYU pragma: keep
+#include "furc/ast/statement.hpp"   // IWYU pragma: keep
+
+#include <iostream>
+
+namespace furc::front {
+
+namespace {
+namespace ir = furlang::ir;
+}
+
+void ir_generator::visit_function_definition_node(const ast::function_definition_node& funcDef) {
+    auto func = std::make_unique<furlang::ir::function>(std::string(funcDef.name()->string));
+
+    m_currentBlock = func->push();
+    if (funcDef.body().has_error()) {
+        std::cerr << funcDef.body().error() << '\n';
+        return;
+    }
+    for (const auto& stmt : funcDef.body()->statements) {
+        stmt->accept(*this);
+    }
+
+    m_module.push(std::move(func));
+}
+
+void ir_generator::visit_return_statement_node(const ast::return_statement_node& returnStmt) {
+    if (returnStmt.value().has_error()) {
+        std::cerr << returnStmt.value() << '\n';
+    }
+
+    if (returnStmt.value().present()) {
+        returnStmt.value()->accept(*this);
+        m_currentBlock->emplace<ir::return_instruction>(ir::operand::new_reg(m_registerCounter - 1));
+    } else {
+        m_currentBlock->emplace<ir::return_instruction>();
+    }
+}
+
+void ir_generator::visit_string_literal_node(const ast::string_literal_node& node) {
+    m_currentBlock->emplace<furlang::ir::assign_instruction>(ir::operand::new_string(std::string(*node.value())),
+        ir::operand::new_reg(m_registerCounter++));
+}
+
+void ir_generator::visit_integer_literal_node(const ast::integer_literal_node& node) {
+    m_currentBlock->emplace<furlang::ir::assign_instruction>(ir::operand::new_integer(*node.value()),
+        ir::operand::new_reg(m_registerCounter++));
+}
+
+void ir_generator::visit_var_read_expression_node(const ast::var_read_expression_node& node) {
+    throw std::runtime_error("unimplemented");
+}
+
+void ir_generator::visit_unaryop_expression_node(const ast::unaryop_expression_node& node) {
+    throw std::runtime_error("unimplemented");
+}
+
+static inline furlang::ir::binary_op_instruction_t binary_op_instruction_t(ast::binop_expression_node_t type) {
+    switch (type) {
+    case ast::binop_expression_node_t::Add: return furlang::ir::binary_op_instruction_t::Add;
+    case ast::binop_expression_node_t::Sub: return furlang::ir::binary_op_instruction_t::Sub;
+    case ast::binop_expression_node_t::Mul: return furlang::ir::binary_op_instruction_t::Mul;
+    case ast::binop_expression_node_t::Div: return furlang::ir::binary_op_instruction_t::Div;
+    case ast::binop_expression_node_t::Mod: return furlang::ir::binary_op_instruction_t::Mod;
+    case ast::binop_expression_node_t::Equal: return furlang::ir::binary_op_instruction_t::Eq;
+    case ast::binop_expression_node_t::NotEqual: return furlang::ir::binary_op_instruction_t::NotEq;
+    case ast::binop_expression_node_t::LessThan: return furlang::ir::binary_op_instruction_t::LessThan;
+    case ast::binop_expression_node_t::GreaterThan: return furlang::ir::binary_op_instruction_t::GreaterThan;
+    case ast::binop_expression_node_t::LessEqual: return furlang::ir::binary_op_instruction_t::LessEq;
+    case ast::binop_expression_node_t::GreaterEqual: return furlang::ir::binary_op_instruction_t::GreaterEq;
+    case ast::binop_expression_node_t::None:
+    default: throw std::runtime_error("unreachable");
+    }
+}
+
+void ir_generator::visit_binop_expression_node(const ast::binop_expression_node& node) {
+    node.lhs()->accept(*this);
+    std::uint32_t lhs = m_registerCounter - 1;
+    node.rhs()->accept(*this);
+    std::uint32_t rhs = m_registerCounter - 1;
+    std::uint32_t dst = m_registerCounter++;
+    m_currentBlock->emplace<furlang::ir::binary_op_instruction>(binary_op_instruction_t(node.type()),
+        ir::operand::new_reg(lhs),
+        ir::operand::new_reg(rhs),
+        ir::operand::new_reg(dst));
+}
+
+void ir_generator::visit_var_assign_expression_node(const ast::var_assign_expression_node& node) {
+    throw std::runtime_error("unimplemented");
+}
+
+} // namespace furc::front

furc/src/main.cpp

@@ -1,14 +1,34 @@
-#ifndef LIBFURC
+// #ifndef LIBFURC
 
+#include "furc/front/ir_generator.hpp"
 #include "furc/front/parser.hpp"
 
 #include <iostream>
 
 int main(void) {
-    furc::front::parser parser("<TEMP>", "func main() {\n    return x = y;\n}");
-    std::cout << parser.parse() << '\n';
+    furc::front::parser       parser("<TEMP>", "func main() {\n    return 7 + 6 * 10;\n}");
+    furc::front::ir_generator generator;
+
+    auto program = parser.parse();
+    if (program.has_error()) {
+        std::cerr << program << '\n';
+    }
+    program->accept(generator);
+
+    auto module = std::move(generator.move_module());
+    std::cout << "Generated IR:\n";
+    for (const auto& function : module.functions()) {
+        std::cout << function->name() << ":\n";
+        furlang::ir::block_index blockIndex = 0;
+        for (const auto& block : function->blocks()) {
+            std::cout << "  # block " << blockIndex++ << '\n';
+            for (const auto& instruction : block->instructions()) {
+                std::cout << "  " << *instruction << '\n';
+            }
+        }
+    }
 
     return 0;
 }
 
-#endif // LIBFURC
+// #endif // LIBFURC

furlang/include/furlang/ir/block.hpp

@@ -13,13 +13,13 @@ namespace ir {
 // https://en.wikipedia.org/wiki/Basic_block
 class block {
 public:
-    using value_type = std::shared_ptr<instruction>;
+    using value_type = std::unique_ptr<instruction>;
 public:
     block() = default;
 public:
     template <typename T, typename... Args, typename = std::enable_if_t<std::is_base_of_v<instruction, T>>>
     void emplace(Args&&... args) {
-        m_instructions.emplace_back(std::make_shared<T>(std::forward<Args>(args)...));
+        m_instructions.emplace_back(std::make_unique<T>(std::forward<Args>(args)...));
     }
 
     std::vector<value_type>&       instructions() { return m_instructions; }

furlang/include/furlang/ir/function.hpp

@@ -0,0 +1,35 @@
+#ifndef FURLANG_IR_FUNCTION_HPP
+#define FURLANG_IR_FUNCTION_HPP
+
+#include "furlang/ir/block.hpp"
+
+#include <memory>
+#include <vector>
+
+namespace furlang {
+namespace ir {
+
+class function {
+public:
+    using value_type = std::shared_ptr<block>;
+public:
+    function(const std::string& name)
+      : m_name(name) {}
+
+    function(std::string&& name)
+      : m_name(std::move(name)) {}
+public:
+    const std::string& name() const { return m_name; }
+
+    value_type push() { return m_blocks.emplace_back(std::make_shared<block>()); }
+
+    const std::vector<value_type>& blocks() const { return m_blocks; }
+private:
+    std::string             m_name;
+    std::vector<value_type> m_blocks;
+};
+
+} // namespace ir
+} // namespace furlang
+
+#endif // FURLANG_IR_FUNCTION_HPP

furlang/include/furlang/ir/instruction.hpp

@@ -4,6 +4,8 @@
 #include "furlang/ir/operand.hpp"
 
 #include <cstdint>
+#include <optional>
+#include <ostream>
 
 namespace furlang {
 namespace ir {
@@ -15,6 +17,7 @@ enum class instruction_t {
     Call,
     Branch,
     BranchCond,
+    Return,
 };
 
 class instruction {
@@ -28,6 +31,26 @@ public:
     instruction& operator=(const instruction&) = delete;
 public:
     virtual instruction_t type() const = 0;
+public:
+    friend std::ostream& operator<<(std::ostream& os, const instruction& instruction) { return instruction.print(os); }
+protected:
+    virtual std::ostream& print(std::ostream& os) const = 0;
+};
+
+class alloca_instruction final : public instruction {
+public:
+    alloca_instruction() {}
+
+    ~alloca_instruction() override = default;
+
+    alloca_instruction(alloca_instruction&&)                 = default;
+    alloca_instruction& operator=(alloca_instruction&&)      = default;
+    alloca_instruction(const alloca_instruction&)            = delete;
+    alloca_instruction& operator=(const alloca_instruction&) = delete;
+public:
+    instruction_t type() const override { return instruction_t::Alloca; }
+protected:
+    std::ostream& print(std::ostream& os) const override { return os << "alloca"; }
 };
 
 class assign_instruction final : public instruction {
@@ -49,6 +72,10 @@ public:
 private:
     operand m_source;
     operand m_destination;
+protected:
+    std::ostream& print(std::ostream& os) const override {
+        return os << "assign " << m_source << ", " << m_destination;
+    }
 };
 
 enum class binary_op_instruction_t {
@@ -66,6 +93,23 @@ enum class binary_op_instruction_t {
     GreaterEq,
 };
 
+static inline std::ostream& operator<<(std::ostream& os, binary_op_instruction_t type) {
+    switch (type) {
+    case binary_op_instruction_t::Add: return os << '+';
+    case binary_op_instruction_t::Sub: return os << '-';
+    case binary_op_instruction_t::Mul: return os << '*';
+    case binary_op_instruction_t::Div: return os << '/';
+    case binary_op_instruction_t::Mod: return os << '%';
+    case binary_op_instruction_t::Eq: return os << "==";
+    case binary_op_instruction_t::NotEq: return os << "!=";
+    case binary_op_instruction_t::LessThan: return os << '<';
+    case binary_op_instruction_t::GreaterThan: return os << '>';
+    case binary_op_instruction_t::LessEq: return os << "<=";
+    case binary_op_instruction_t::GreaterEq: return os << ">=";
+    }
+    return os;
+}
+
 class binary_op_instruction final : public instruction {
 public:
     binary_op_instruction(binary_op_instruction_t type, operand&& lhs, operand&& rhs, operand&& dst)
@@ -89,6 +133,10 @@ private:
     operand                 m_lhs;
     operand                 m_rhs;
     operand                 m_dst;
+protected:
+    std::ostream& print(std::ostream& os) const override {
+        return os << "binop(" << m_type << ") " << m_lhs << ", " << m_rhs << ", " << m_dst;
+    }
 };
 
 using block_index = std::uint64_t;
@@ -110,6 +158,8 @@ public:
     block_index block() const { return m_block; }
 private:
     block_index m_block;
+protected:
+    std::ostream& print(std::ostream& os) const override { return os << "branch #" << m_block; }
 };
 
 class branch_cond_instruction final : public instruction {
@@ -133,6 +183,36 @@ private:
     operand     m_condition;
     block_index m_ifBlock;
     block_index m_elseBlock;
+protected:
+    std::ostream& print(std::ostream& os) const override {
+        return os << "branch_cond " << m_condition << ", #" << m_ifBlock << ", #" << m_elseBlock;
+    }
+};
+
+class return_instruction final : public instruction {
+public:
+    return_instruction() {}
+    return_instruction(operand&& value)
+      : m_value(std::move(value)) {}
+
+    ~return_instruction() override = default;
+
+    return_instruction(return_instruction&&)                 = default;
+    return_instruction& operator=(return_instruction&&)      = default;
+    return_instruction(const return_instruction&)            = delete;
+    return_instruction& operator=(const return_instruction&) = delete;
+public:
+    instruction_t type() const override { return instruction_t::Return; }
+
+    const std::optional<operand>& value() const { return m_value; }
+private:
+    std::optional<operand> m_value;
+protected:
+    std::ostream& print(std::ostream& os) const override {
+        os << "return";
+        if (m_value.has_value()) os << ' ' << m_value.value();
+        return os;
+    }
 };
 
 } // namespace ir

furlang/include/furlang/ir/module.hpp

@@ -0,0 +1,32 @@
+#ifndef FURLANG_IR_MODULE_HPP
+#define FURLANG_IR_MODULE_HPP
+
+#include "furlang/ir/function.hpp"
+
+#include <memory>
+#include <vector>
+
+namespace furlang {
+namespace ir {
+
+class module {
+public:
+    using value_type = std::unique_ptr<function>;
+public:
+    module() = default;
+public:
+    template <typename... Args>
+    value_type& push(Args&&... args) {
+        return m_functions.emplace_back(std::forward<Args>(args)...);
+    }
+
+    std::vector<value_type>&       functions() { return m_functions; }
+    const std::vector<value_type>& functions() const { return m_functions; }
+private:
+    std::vector<value_type> m_functions;
+};
+
+} // namespace ir
+} // namespace furlang
+
+#endif // FURLANG_IR_MODULE_HPP

furlang/include/furlang/ir/operand.hpp

@@ -2,6 +2,7 @@
 #define FURLANG_IR_OPERAND_HPP
 
 #include <cstdint>
+#include <ostream>
 #include <string>
 
 namespace furlang {
@@ -97,6 +98,16 @@ public:
 
     register_operand reg() const { return m_value.reg; }
     integer_operand  integer() const { return m_value.integer; }
+public:
+    friend std::ostream& operator<<(std::ostream& os, const operand& operand) {
+        switch (operand.m_type) {
+        case operand_t::None: return os << "none";
+        case operand_t::Register: return os << '%' << operand.m_value.reg;
+        case operand_t::Integer: return os << operand.m_value.integer;
+        case operand_t::String: return os << '"' << operand.m_value.string << '"';
+        }
+        return os;
+    }
 private:
     operand() = default;
 private: