From 8db23dbd3c372132b9b68b488cc0b937e7d29423 Mon Sep 17 00:00:00 2001
From: bog <bog@gozmail.net>
Date: Sun, 17 Sep 2023 21:36:58 +0200
Subject: [PATCH] ADD: program and vm for integers.

---
 meson.build      |  6 +++-
 src/Compiler.cpp | 42 ++++++++++++++++++++++++++
 src/Compiler.hpp | 26 ++++++++++++++++
 src/Constant.cpp | 38 +++++++++++++++++++++++
 src/Constant.hpp | 34 +++++++++++++++++++++
 src/Module.cpp   | 17 ++++++++++-
 src/Module.hpp   |  6 +++-
 src/Program.cpp  | 68 +++++++++++++++++++++++++++++++++++++++++
 src/Program.hpp  | 45 ++++++++++++++++++++++++++++
 src/VM.cpp       | 78 ++++++++++++++++++++++++++++++++++++++++++++++++
 src/VM.hpp       | 34 +++++++++++++++++++++
 src/common.hpp   |  1 +
 src/main.cpp     | 60 +++++++++++++++++++++++++++++++++++--
 13 files changed, 450 insertions(+), 5 deletions(-)
 create mode 100644 src/Compiler.cpp
 create mode 100644 src/Compiler.hpp
 create mode 100644 src/Constant.cpp
 create mode 100644 src/Constant.hpp
 create mode 100644 src/Program.cpp
 create mode 100644 src/Program.hpp
 create mode 100644 src/VM.cpp
 create mode 100644 src/VM.hpp

diff --git a/meson.build b/meson.build
index 3dd5a81..3124f82 100644
--- a/meson.build
+++ b/meson.build
@@ -16,7 +16,11 @@ zarn_lib = shared_library('zarn',
                             'src/Node.cpp',
                             'src/Logger.cpp',
                             'src/Lexer.cpp',
-                            'src/Parser.cpp'
+                            'src/Parser.cpp',
+                            'src/Compiler.cpp',
+                            'src/Program.cpp',
+                            'src/VM.cpp',
+                            'src/Constant.cpp',
                           ],
                           install: true)
 
diff --git a/src/Compiler.cpp b/src/Compiler.cpp
new file mode 100644
index 0000000..535fadc
--- /dev/null
+++ b/src/Compiler.cpp
@@ -0,0 +1,42 @@
+#include "Compiler.hpp"
+#include "src/Node.hpp"
+#include "src/Program.hpp"
+
+namespace zn
+{
+  /*explicit*/ Compiler::Compiler(Logger& logger)
+    : m_logger { logger }
+  {
+  }
+
+  /*virtual*/ Compiler::~Compiler()
+  {
+  }
+
+  void Compiler::compile(Node const& node, Program& program)
+  {
+    switch (node.type())
+      {
+      case NODE_MODULE: {
+        for (size_t i=0; i<node.size(); i++)
+          {
+            compile(*node.child_at(i), program);
+            program.append(OPCODE_POP);
+          }
+      } break;
+
+      case NODE_INT: {
+        size_t addr = program
+          .add_constant(std::make_shared<Constant>
+                        (TYPE_INT, std::stoi(node.repr())));
+        program.append(OPCODE_LOAD_CONST, addr);
+      } break;
+
+      default: {
+        std::cerr << "cannot compile node '"
+                  << node.string() << "'" << std::endl;
+        abort();
+      } break;
+      }
+  }
+}
diff --git a/src/Compiler.hpp b/src/Compiler.hpp
new file mode 100644
index 0000000..b6fe70b
--- /dev/null
+++ b/src/Compiler.hpp
@@ -0,0 +1,26 @@
+#ifndef zn_COMPILER_HPP
+#define zn_COMPILER_HPP
+
+#include "common.hpp"
+#include "Logger.hpp"
+#include "Node.hpp"
+#include "Program.hpp"
+
+namespace zn
+{
+  ZN_ERROR(compile_error);
+
+  class Compiler
+  {
+  public:
+    explicit Compiler(Logger& logger);
+    virtual ~Compiler();
+
+    void compile(Node const& node, Program& program);
+
+  private:
+    Logger& m_logger;
+  };
+}
+
+#endif
diff --git a/src/Constant.cpp b/src/Constant.cpp
new file mode 100644
index 0000000..2d610ef
--- /dev/null
+++ b/src/Constant.cpp
@@ -0,0 +1,38 @@
+#include "Constant.hpp"
+
+namespace zn
+{
+  /*explicit*/ Constant::Constant(Type type, value_t value)
+    : m_type { type }
+    , m_value { value }
+  {
+  }
+
+  /*virtual*/ Constant::~Constant()
+  {
+  }
+
+  bool Constant::equals(Constant const& rhs) const
+  {
+    if (m_type != rhs.m_type)
+      {
+        return false;
+      }
+
+    return m_value == rhs.m_value;
+  }
+
+  std::string Constant::string() const
+  {
+    if (auto val = std::get_if<int>(&(*m_value));
+        val)
+      {
+        return std::to_string(*val);
+      }
+
+    std::cerr << "cannot stringify "
+              << (TypeStr[m_type] + strlen("TYPE_"))
+              << std::endl;
+    abort();
+  }
+}
diff --git a/src/Constant.hpp b/src/Constant.hpp
new file mode 100644
index 0000000..07e6037
--- /dev/null
+++ b/src/Constant.hpp
@@ -0,0 +1,34 @@
+#ifndef zn_CONSTANT_HPP
+#define zn_CONSTANT_HPP
+
+#include "common.hpp"
+
+#define TYPES(G) \
+  G(TYPE_NIL),   \
+    G(TYPE_INT)
+
+namespace zn
+{
+  ZN_MK_ENUM(Type, TYPES);
+
+  using value_t = std::optional<std::variant<int>>;
+
+  class Constant
+  {
+  public:
+    explicit Constant(Type type, value_t value);
+    virtual ~Constant();
+
+    value_t value() const { return m_value; }
+    Type type() const { return m_type; }
+
+    bool equals(Constant const& rhs) const;
+    std::string string() const;
+
+  private:
+    Type m_type;
+    value_t m_value;
+  };
+}
+
+#endif
diff --git a/src/Module.cpp b/src/Module.cpp
index cfb80f5..a949b05 100644
--- a/src/Module.cpp
+++ b/src/Module.cpp
@@ -1,6 +1,9 @@
 #include "Module.hpp"
 #include "Lexer.hpp"
 #include "Parser.hpp"
+#include "Program.hpp"
+#include "Compiler.hpp"
+#include "VM.hpp"
 
 namespace zn
 {
@@ -39,6 +42,18 @@ namespace zn
     Parser parser { m_logger };
 
     auto ast = parser.parse(lexer.all());
-    std::cout << ast->string() << std::endl;
+
+    Compiler compiler { m_logger };
+    compiler.compile(*ast, m_program);
+
+    m_vm.execute(m_program);
+  }
+
+  std::string Module::string() const
+  {
+    std::stringstream ss;
+    ss << m_program.string() << "\n";
+    ss << m_vm.string() << "\n";
+    return ss.str();
   }
 }
diff --git a/src/Module.hpp b/src/Module.hpp
index fbc356a..e2d19a0 100644
--- a/src/Module.hpp
+++ b/src/Module.hpp
@@ -3,6 +3,8 @@
 
 #include "common.hpp"
 #include "Logger.hpp"
+#include "VM.hpp"
+#include "Program.hpp"
 
 namespace zn
 {
@@ -16,10 +18,12 @@ namespace zn
 
     void load_from_file(std::filesystem::path file_path);
 
+    std::string string() const;
   private:
     Logger& m_logger;
     std::string m_source;
-
+    Program m_program;
+    VM m_vm;
   };
 }
 
diff --git a/src/Program.cpp b/src/Program.cpp
new file mode 100644
index 0000000..db1ce11
--- /dev/null
+++ b/src/Program.cpp
@@ -0,0 +1,68 @@
+#include "Program.hpp"
+
+namespace zn
+{
+  /*explicit*/ Program::Program()
+  {
+  }
+
+  /*virtual*/ Program::~Program()
+  {
+  }
+
+  void Program::append(Opcode opcode, int param)
+  {
+    m_instrs.push_back(Instr {opcode, param});
+  }
+
+  Instr Program::instr(size_t index) const
+  {
+    assert(index < size());
+    return m_instrs[index];
+  }
+
+  size_t Program::add_constant(std::shared_ptr<Constant> constant)
+  {
+    for (size_t i=0; i<const_size(); i++)
+      {
+        if (m_constant_pool[i]->equals(*constant))
+          {
+            return i;
+          }
+      }
+
+    m_constant_pool.push_back(constant);
+    return m_constant_pool.size() - 1;
+  }
+
+  std::shared_ptr<Constant> Program::constant(size_t index) const
+  {
+    assert(index < const_size());
+    return m_constant_pool[index];
+  }
+
+  std::string Program::string() const
+  {
+    std::stringstream ss;
+
+    ss << "======== Instructions ========\n";
+    for (size_t i=0; i<size(); i++)
+      {
+        ss << i
+           << "\t"
+           << (OpcodeStr[m_instrs[i].opcode] + strlen("OPCODE_"))
+           << "\t" << (m_instrs[i].param == NO_PARAM ? ""
+                       : std::to_string(m_instrs[i].param))
+           << "\n";
+      }
+
+    ss << "======== Constant Pool ========\n";
+
+    for (size_t i=0; i<const_size(); i++)
+      {
+        ss << i << "\t" << m_constant_pool[i]->string() << "\n";
+      }
+
+    return ss.str();
+  }
+}
diff --git a/src/Program.hpp b/src/Program.hpp
new file mode 100644
index 0000000..4f86523
--- /dev/null
+++ b/src/Program.hpp
@@ -0,0 +1,45 @@
+#ifndef zn_PROGRAM_HPP
+#define zn_PROGRAM_HPP
+
+#include "common.hpp"
+#include "Constant.hpp"
+
+#define NO_PARAM (-1)
+
+#define OPCODES(G) \
+  G(OPCODE_LOAD_CONST),                         \
+    G(OPCODE_POP)
+
+namespace zn
+{
+  ZN_MK_ENUM(Opcode, OPCODES);
+
+  struct Instr {
+    Opcode opcode;
+    int param;
+  };
+
+  class Program
+  {
+  public:
+    explicit Program();
+    virtual ~Program();
+
+    size_t size() const { return m_instrs.size(); }
+    size_t const_size() const { return m_constant_pool.size(); }
+
+    void append(Opcode opcode, int param=NO_PARAM);
+    Instr instr(size_t index) const;
+
+    size_t add_constant(std::shared_ptr<Constant> constant);
+    std::shared_ptr<Constant> constant(size_t index) const;
+
+    std::string string() const;
+
+  private:
+    std::vector<Instr> m_instrs;
+    std::vector<std::shared_ptr<Constant>> m_constant_pool;
+  };
+}
+
+#endif
diff --git a/src/VM.cpp b/src/VM.cpp
new file mode 100644
index 0000000..27aa3ec
--- /dev/null
+++ b/src/VM.cpp
@@ -0,0 +1,78 @@
+#include "VM.hpp"
+#include "src/Program.hpp"
+
+namespace zn
+{
+  /*explicit*/ VM::VM()
+  {
+  }
+
+  /*virtual*/ VM::~VM()
+  {
+  }
+
+  void VM::execute(Program& program)
+  {
+    m_pc = 0;
+    m_frames.push_back(Frame {program});
+
+    while (m_pc < program.size())
+      {
+        auto instr = program.instr(m_pc);
+        execute(instr.opcode, instr.param);
+      }
+  }
+
+  void VM::execute(Opcode opcode, int param)
+  {
+    switch (opcode)
+      {
+      case OPCODE_LOAD_CONST: {
+        push(param);
+        m_pc++;
+      } break;
+
+      case OPCODE_POP: {
+        pop();
+        m_pc++;
+      } break;
+
+      default: {
+        std::cerr << "cannot execute opcode '"
+                  << OpcodeStr[opcode]
+                  << "'" << std::endl;
+        abort();
+      } break;
+      }
+  }
+
+  std::string VM::string() const
+  {
+    std::stringstream ss;
+
+    ss << "======== VM Stack ========\n";
+
+    size_t addr = 0;
+
+    for (int val: m_stack)
+      {
+        ss << addr << " " << val << "\n";
+        addr++;
+      }
+
+    return ss.str();
+  }
+
+  void VM::push(int value)
+  {
+    m_stack.push_back(value);
+  }
+
+  int VM::pop()
+  {
+    assert(m_stack.size() > 0);
+    int value = m_stack.back();
+    m_stack.pop_back();
+    return value;
+  }
+}
diff --git a/src/VM.hpp b/src/VM.hpp
new file mode 100644
index 0000000..63cd995
--- /dev/null
+++ b/src/VM.hpp
@@ -0,0 +1,34 @@
+#ifndef zn_VM_HPP
+#define zn_VM_HPP
+
+#include "common.hpp"
+#include "Program.hpp"
+
+namespace zn
+{
+  struct Frame {
+    Program& program;
+  };
+
+  class VM
+  {
+  public:
+    explicit VM();
+    virtual ~VM();
+
+    void execute(Program& program);
+    void execute(Opcode opcode, int param);
+
+    std::string string() const;
+
+  private:
+    std::vector<Frame> m_frames;
+    std::vector<int> m_stack;
+    size_t m_pc = 0;
+
+    void push(int value);
+    int pop();
+  };
+}
+
+#endif
diff --git a/src/common.hpp b/src/common.hpp
index 664a6cc..3ff4e27 100644
--- a/src/common.hpp
+++ b/src/common.hpp
@@ -17,6 +17,7 @@
 
 #include <cassert>
 #include <fstream>
+#include <variant>
 #include <iostream>
 #include <functional>
 #include <unordered_map>
diff --git a/src/main.cpp b/src/main.cpp
index a5e70df..718312a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,15 +1,71 @@
 #include <iostream>
+#include <getopt.h>
 #include "Module.hpp"
 
 int main(int argc, char** argv)
 {
+  bool debug_mode = false;
 
-  if (argc > 1)
+  while (true)
+    {
+      static struct option options[] = {
+        {"debug", no_argument, 0, 'd'},
+        {"help", no_argument, 0, 'h'},
+        {0, 0, 0, 0}
+      };
+
+      int opt_index;
+      int c = getopt_long(argc, argv, "hd", options, &opt_index);
+
+      if (c == -1) { break; }
+
+      switch (c)
+        {
+        case 'h': {
+          std::stringstream ss;
+          ss << "Usage: zarn [OPTIONS]... <source_file>" << "\n";
+
+          ss << "\n\t" << "[OPTIONS]" << "\n";
+
+          ss << "\t" << "-d, --debug"
+             << "\t" << "show debug informations." << "\n";
+
+          ss << "\t" << "-h, --help"
+             << "\t" << "show this message." << "\n";
+          std::cout << ss.str() << std::endl;
+          return 0;
+        } break;
+
+        case 'd': {
+          debug_mode = true;
+        } break;
+
+        default: break;
+        }
+    }
+
+  if (optind < argc)
     {
       zn::Logger logger;
       zn::Module mod { logger };
 
-      mod.load_from_file(argv[1]);
+      if (debug_mode)
+        {
+          mod.load_from_file(argv[optind]);
+          std::cout << mod.string() << std::endl;
+        }
+      else
+        {
+          try
+            {
+              mod.load_from_file(argv[optind]);
+            }
+          catch(std::exception const& err)
+            {
+              std::cerr << err.what() << std::endl;
+              return -1;
+            }
+        }
     }
 
   return 0;