f

Author: XingfengYang

.gitignore

@@ -0,0 +1,12 @@
+cmake-build-debug/
+cmake_install.cmake
+CmakeFiles
+CMakeCache.txt
+lc3
+lc3.cbp
+Makefile
+.idea
+*/CMakeFiles
+*/cmake_install.cmake
+*/mian.cpp.o
+*/vm.cpp.o

CMakeLists.txt

@@ -0,0 +1,9 @@
+cmake_minimum_required(VERSION 3.0)
+
+set(CMAKE_BUILD_TYPE Debug)
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14")
+
+project(lc3)
+
+add_subdirectory (src)
+add_subdirectory (test)

include/vm.h

@@ -0,0 +1,107 @@
+//
+// Created by XingfengYang on 2019-08-03.
+//
+
+#ifndef LC3_VM_H
+#define LC3_VM_H
+
+
+#include <vector>
+
+namespace lc3 {
+
+    enum REG {
+        R0,
+        R1,
+        R2,
+        R3,
+        R4,
+        R5,
+        R6,
+        R7,
+        PC, /* program counter */
+        COND, /* condition flag */
+        REG_COUNT
+    };
+
+    enum OP_CODE {
+        OP_BR = 0b0000, /* branch */
+        OP_ADD = 0b0001, /* add */
+        OP_LD = 0b0010, /* load */
+        OP_ST = 0b0011, /* store */
+        OP_JSR = 0b0100, /* jump register */
+        OP_AND = 0b0101, /* and */
+        OP_LDR = 0b0110, /* load register */
+        OP_STR = 0b0111, /* store register */
+        OP_RTI = 0b1000, /* not used */
+        OP_NOT = 0b1001, /* not */
+        OP_LDI = 0b1010, /* load indirect */
+        OP_STI = 0b1011, /* store indirect */
+        OP_JMP = 0b1100, /* jump */
+        OP_RES = 0b1101, /* reserved (unused) */
+        OP_LEA = 0b1110, /* load effective address */
+        OP_TRAP = 0b1111, /* execute trap */
+    };
+
+    enum COND_FLAG {
+        FL_POS = 1 << 0, /* positive */
+        FL_ZRO = 1 << 1, /* zero */
+        FL_NEG = 1 << 2,  /* negative */
+    };
+
+    enum Trap{
+        TRAP_GETC = 0x20, /* get char from keyboard but not echo onto terminal  */
+        TRAP_OUT = 0x21, /* echo a char onto terminal */
+        TRAP_PUTS = 0x22, /* echo a word string onto terminal */
+        TRAP_IN = 0x23, /* get char from keyboard and echo onto terminal */
+        TRAP_PUTSP = 0x24, /* output a byte string */
+        TRAP_HALT = 0x25, /* halt program */
+    };
+
+    class VM {
+    private:
+        bool running = false;
+
+        uint16_t *memory; /* memory */
+
+        uint16_t registers[REG_COUNT];
+
+    private:
+
+        /* fetch instruction from memory */
+        uint16_t fetch();
+
+        /* signed extend */
+        uint16_t signExtend(uint16_t source,uint16_t numberOfDigits);
+
+        void updateFlag(uint16_t reg);
+
+        /* decode instruction into opcode and args */
+        uint16_t decode(uint16_t instruction);
+
+        /* execute opcode */
+        void execute(uint16_t opcode, uint16_t instruction);
+
+        void executeTrap(uint16_t trapCode);
+
+        /* load from memory */
+        uint16_t readMemory(uint16_t address);
+
+        /* write into memory */
+        uint16_t writeMemory(uint16_t address, uint16_t value);
+
+    public:
+        VM();
+
+        void loadProgram(std::vector<uint16_t> prog);
+
+        void run();
+
+        ~VM();
+
+    };
+
+};
+
+
+#endif //LC3_VM_H

src/CMakeLists.txt

@@ -0,0 +1,5 @@
+add_executable(
+        lc3
+        mian.cpp
+        vm.cpp
+)

src/mian.cpp

@@ -0,0 +1,34 @@
+//
+// Created by XingfengYang on 2019-08-03.
+//
+
+#include <iostream>
+#include "../include/vm.h"
+
+
+int main(int argc, char *argv[]){
+
+
+    /**
+     * ADD R0,R0,0
+     * ADD R1,R1,3
+     * ADD R0,R1,R1
+     */
+    std::vector<uint16_t> prog;
+
+    prog.push_back(0b0001000000100000); /* ADD R0 R0 0 */
+    prog.push_back(0b0001001001101111); /* ADD R1 R1 15 */
+    prog.push_back(0b0001000001000001); /* ADD R0 R1 R0 */
+    prog.push_back(0b1111000000100001); /* trap out R0 */
+    prog.push_back(0b0001000000100001); /* ADD R0 R0 1 */
+    prog.push_back(0b1111000000100001); /* trap out R0 */
+    prog.push_back(0b1111000000100101); /* trap halt */
+
+    std::cout<<"=========lc3========"<<std::endl;
+    lc3::VM vm;
+    vm.loadProgram(prog);
+    vm.run();
+
+
+    return 0;
+}