From c28474940a2ba9784317a30ec17cc68ffa47bf91 Mon Sep 17 00:00:00 2001
From: avinal <185067@nith.ac.in>
Date: Tue, 18 Aug 2020 21:31:36 +0530
Subject: [PATCH] working code writer program

---
 code_writer.cpp | 390 ++++++++++++++++++++++++++++++++++++++++++++++++
 code_writer.hpp |  28 ++++
 2 files changed, 418 insertions(+)
 create mode 100644 code_writer.cpp
 create mode 100644 code_writer.hpp

diff --git a/code_writer.cpp b/code_writer.cpp
new file mode 100644
index 0000000..600541f
--- /dev/null
+++ b/code_writer.cpp
@@ -0,0 +1,390 @@
+#include "code_writer.hpp"
+
+code_writer::code_writer(std::string name)
+{
+    file_name = name;
+    name.erase(name.find('.'));
+    name.append(".asm");
+    outfile.open(name);
+}
+
+void code_writer::write_assembly()
+{
+    parser toparse(file_name);
+    toparse.parse();
+    commands = toparse.get_commands();
+
+    std::unordered_map<c_type,
+                       std::function<void(std::string, int, bool)>>
+        write_map({{C_ARITHMETIC,
+                    [this](std::string arg1, int arg2, bool arg3) {
+                        this->write_arithmetic(arg1, arg2, arg3);
+                    }},
+                   {C_PUSH,
+                    [this](std::string arg1, int arg2, bool arg3) {
+                        this->write_push(arg1, arg2, arg3);
+                    }},
+                   {C_POP,
+                    [this](std::string arg1, int arg2, bool arg3) {
+                        this->write_pop(arg1, arg2, arg3);
+                    }}});
+
+    for (auto curr : commands)
+    {
+        c_type write_type;
+        std::string instruction;
+        int index;
+        std::tie(write_type, instruction, index) = curr;
+        if (outfile.is_open())
+        {
+            write_map[write_type](instruction, index, this->dbg);
+        }
+    }
+    outfile.close();
+}
+
+void code_writer::write_push(std::string segment, int index, bool debug)
+{
+    std::string toname = file_name;
+    toname = toname.substr(toname.find_last_of('/') + 1);
+    toname = toname.erase(toname.find('.'));
+
+    if (debug)
+    {
+        outfile << "// push " << segment << " " << index << std::endl;
+    }
+
+    if (segment == "constant")
+    {
+        outfile << "@" << index << std::endl
+                << "D=A" << std::endl
+                << "@SP" << std::endl
+                << "AM=M+1" << std::endl
+                << "A=A-1" << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 6;
+    }
+    else if (segment == "static")
+    {
+        outfile << "@" << toname << "." << index << std::endl
+                << "D=M" << std::endl
+                << "@SP" << std::endl
+                << "AM=M+1" << std::endl
+                << "A=A-1" << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 6;
+    }
+    else if (segment == "pointer")
+    {
+        std::string which = (index == 0) ? "THIS" : "THAT";
+        outfile << "@" << which << std::endl
+                << "D=M" << std::endl
+                << "@SP" << std::endl
+                << "AM=M+1" << std::endl
+                << "A=A-1" << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 6;
+    }
+    else if (segment == "temp")
+    {
+        outfile << "@" << index + 5 << std::endl
+                << "D=M" << std::endl
+                << "@SP" << std::endl
+                << "AM=M+1" << std::endl
+                << "A=A-1" << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 6;
+    }
+    else
+    {
+        std::string which;
+        if (segment == "local")
+        {
+            which = "LCL";
+        }
+        else if (segment == "argument")
+        {
+            which = "ARG";
+        }
+        else if (segment == "this")
+        {
+            which = "THIS";
+        }
+        else if (segment == "that")
+        {
+            which = "THAT";
+        }
+        outfile << "@" << which << std::endl
+                << "D=M" << std::endl
+                << "@" << index << std::endl
+                << "D=D+A" << std::endl
+                << "A=D" << std::endl
+                << "D=M" << std::endl
+                << "@SP" << std::endl
+                << "AM=M+1" << std::endl
+                << "A=A-1" << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 10;
+    }
+}
+
+void code_writer::write_pop(std::string segment, int index, bool debug)
+{
+    std::string toname = file_name;
+    toname = toname.substr(toname.find_last_of('/')+1);
+    toname = toname.erase(toname.find('.'));
+
+    if (debug && segment != "constant")
+    {
+        outfile << "// pop " << segment << " " << index << std::endl;
+    }
+
+    if (segment == "static")
+    {
+        outfile << "@SP" << std::endl
+                << "AM=M-1" << std::endl
+                << "D=M" << std::endl
+                << "@" << toname << "." << index << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 5;
+    }
+    else if (segment == "pointer")
+    {
+        std::string which = (index == 0) ? "THIS" : "THAT";
+        outfile << "@SP" << std::endl
+                << "AM=M-1" << std::endl
+                << "D=M" << std::endl
+                << "@" << which << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 4;
+    }
+    else if (segment == "temp")
+    {
+        outfile << "@SP" << std::endl
+                << "AM=M-1" << std::endl
+                << "D=M" << std::endl
+                << "@" << index + 5 << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 5;
+    }
+    else
+    {
+        std::string which;
+        if (segment == "local")
+        {
+            which = "LCL";
+        }
+        else if (segment == "argument")
+        {
+            which = "ARG";
+        }
+        else if (segment == "this")
+        {
+            which = "THIS";
+        }
+        else if (segment == "that")
+        {
+            which = "THAT";
+        }
+        outfile << "@" << which << std::endl
+                << "D=M" << std::endl
+                << "@" << index << std::endl
+                << "D=D+A" << std::endl
+                << "@R13" << std::endl
+                << "M=D" << std::endl
+                << "@SP" << std::endl
+                << "AM=M-1" << std::endl
+                << "D=M" << std::endl
+                << "@R13" << std::endl
+                << "A=M" << std::endl
+                << "M=D" << std::endl;
+        this->ins_no += 12;
+    }
+}
+
+void code_writer::write_arithmetic(std::string comm, int index, bool debug)
+{
+    std::unordered_map<std::string,
+                       std::function<void(bool)>>
+        arith_mapic({
+            {"add",
+             [this](bool arg1) { this->write_add(arg1); }},
+            {"sub",
+             [this](bool arg1) { this->write_sub(arg1); }},
+            {"neg",
+             [this](bool arg1) { this->write_neg(arg1); }},
+            {"and",
+             [this](bool arg1) { this->write_and(arg1); }},
+            {"or",
+             [this](bool arg1) { this->write_or(arg1); }},
+            {"not",
+             [this](bool arg1) { this->write_not(arg1); }},
+            {"gt",
+             [this](bool arg1) { this->write_gt(arg1); }},
+            {"lt",
+             [this](bool arg1) { this->write_lt(arg1); }},
+            {"eq",
+             [this](bool arg1) { this->write_eq(arg1); }},
+        });
+
+    arith_mapic[comm](debug);
+}
+
+void code_writer::write_add(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// add" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "AM=M-1" << std::endl
+            << "D=M" << std::endl
+            << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=D+M" << std::endl;
+    this->ins_no += 6;
+}
+
+void code_writer::write_sub(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// sub" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "AM=M-1" << std::endl
+            << "D=M" << std::endl
+            << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=M-D" << std::endl;
+    this->ins_no += 6;
+}
+
+void code_writer::write_neg(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// neg" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=-M" << std::endl;
+    this->ins_no += 3;
+}
+
+void code_writer::write_eq(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// eq" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "AM=M-1" << std::endl
+            << "D=M" << std::endl
+            << "A=A-1" << std::endl
+            << "D=M-D" << std::endl;
+    this->ins_no += 5;
+    outfile << "@" << this->ins_no + 6 << std::endl
+            << "D;JEQ" << std::endl
+            << "D=0" << std::endl;
+    this->ins_no += 3;
+    outfile << "@" << this->ins_no + 4 << std::endl
+            << "0;JMP" << std::endl
+            << "D=-1" << std::endl
+            << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=D" << std::endl;
+    this->ins_no += 6;
+}
+
+void code_writer::write_lt(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// lt" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "AM=M-1" << std::endl
+            << "D=M" << std::endl
+            << "A=A-1" << std::endl
+            << "D=M-D" << std::endl;
+    this->ins_no += 5;
+    outfile << "@" << this->ins_no + 6 << std::endl
+            << "D;JLT" << std::endl
+            << "D=0" << std::endl;
+    this->ins_no += 3;
+    outfile << "@" << this->ins_no + 4 << std::endl
+            << "0;JMP" << std::endl
+            << "D=-1" << std::endl
+            << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=D" << std::endl;
+    this->ins_no += 6;
+}
+
+void code_writer::write_gt(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// gt" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "AM=M-1" << std::endl
+            << "D=M" << std::endl
+            << "A=A-1" << std::endl
+            << "D=M-D" << std::endl;
+    this->ins_no += 5;
+    outfile << "@" << this->ins_no + 6 << std::endl
+            << "D;JGT" << std::endl
+            << "D=0" << std::endl;
+    this->ins_no += 3;
+    outfile << "@" << this->ins_no + 4 << std::endl
+            << "0;JMP" << std::endl
+            << "D=-1" << std::endl
+            << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=D" << std::endl;
+    this->ins_no += 6;
+}
+
+void code_writer::write_and(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// and" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "AM=M-1" << std::endl
+            << "D=M" << std::endl
+            << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=D&M" << std::endl;
+    this->ins_no += 6;
+}
+
+void code_writer::write_or(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// or" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "AM=M-1" << std::endl
+            << "D=M" << std::endl
+            << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=D|M" << std::endl;
+    this->ins_no += 6;
+}
+
+void code_writer::write_not(bool debug)
+{
+    if (debug)
+    {
+        outfile << "// not" << std::endl;
+    }
+    outfile << "@SP" << std::endl
+            << "A=M-1" << std::endl
+            << "M=!M" << std::endl;
+    this->ins_no += 3;
+}
\ No newline at end of file
diff --git a/code_writer.hpp b/code_writer.hpp
new file mode 100644
index 0000000..3492ed2
--- /dev/null
+++ b/code_writer.hpp
@@ -0,0 +1,28 @@
+
+#include "parser.hpp"
+#include <functional>
+class code_writer
+{
+private:
+    std::string file_name;
+    std::vector<vmcommand> commands;
+    std::ofstream outfile;
+    int ins_no = -1;
+    bool dbg = false;
+
+public:
+    code_writer(std::string name);
+    void write_assembly();
+    void write_push(std::string segment, int index, bool debug);
+    void write_pop(std::string segment, int index, bool debug);
+    void write_arithmetic(std::string comm, int index, bool debug);
+    void write_add(bool debug);
+    void write_sub(bool debug);
+    void write_neg(bool debug);
+    void write_and(bool debug);
+    void write_or(bool debug);
+    void write_not(bool debug);
+    void write_eq(bool debug);
+    void write_lt(bool debug);
+    void write_gt(bool debug);
+};