From 3758e3da40069a3fd878d534611b84079a39a94e Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Thu, 17 Jul 2025 17:03:49 +0800
Subject: [PATCH 01/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=20SyscallComma?=
 =?UTF-8?q?nd=20=E5=AE=9E=E7=8E=B0?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 在 CommandFactory 中为 VMOpCode.SYSCALL 添加了 SyscallCommand 实现
- 解除了对 SYSCALL 命令的注释，使其可以被使用
---
 src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java b/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
index 4054a11..dbdab0f 100644
--- a/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
+++ b/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
@@ -1,5 +1,6 @@
 package org.jcnc.snow.vm.factories;
 
+import org.jcnc.snow.vm.commands.system.control.SyscallCommand;
 import org.jcnc.snow.vm.commands.type.control.byte8.*;
 import org.jcnc.snow.vm.commands.type.control.double64.*;
 import org.jcnc.snow.vm.commands.type.control.float32.*;
@@ -262,7 +263,7 @@ public class CommandFactory {
 
         // region  System Control (0x0400-0x04FF)
         COMMANDS[VMOpCode.HALT]        = new HaltCommand();
-//        COMMANDS[VMOpCode.SYSCALL]     = new SyscallCommand();
+        COMMANDS[VMOpCode.SYSCALL]     = new SyscallCommand();
 //        COMMANDS[VMOpCode.DEBUG_TRAP]  = new DebugTrapCommand();
         // endregion
 

From bf9190dec658f9e503c83e9d356a455c0e653ab0 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Thu, 17 Jul 2025 17:04:12 +0800
Subject: [PATCH 02/36] =?UTF-8?q?refactor:=20=E7=A7=BB=E9=99=A4=E8=B0=83?=
 =?UTF-8?q?=E8=AF=95=E7=94=A8=E6=8C=87=E4=BB=A4=20DEBUG=5FTRAP?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

移除了 OpHelper 类中 DEBUG_TRAP 指令的映射，以减少不必要的代码。这个修改对现有的功能没有影响，只是为了简化代码结构。
---
 .../java/org/jcnc/snow/compiler/backend/utils/OpHelper.java     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/backend/utils/OpHelper.java b/src/main/java/org/jcnc/snow/compiler/backend/utils/OpHelper.java
index 42c29ff..d006802 100644
--- a/src/main/java/org/jcnc/snow/compiler/backend/utils/OpHelper.java
+++ b/src/main/java/org/jcnc/snow/compiler/backend/utils/OpHelper.java
@@ -176,7 +176,7 @@ public final class OpHelper {
         map.put("MOV", Integer.toString(VMOpCode.MOV));
         map.put("HALT", Integer.toString(VMOpCode.HALT));
         map.put("SYSCALL", Integer.toString(VMOpCode.SYSCALL));
-        map.put("DEBUG_TRAP", Integer.toString(VMOpCode.DEBUG_TRAP));
+//        map.put("DEBUG_TRAP", Integer.toString(VMOpCode.DEBUG_TRAP));
         OPCODE_MAP = Collections.unmodifiableMap(map);
 
         Map<Integer, String> revmap = new HashMap<>();  // reverse map

From 23c6de3601a4039b8bd5700d20687ead9eae9a11 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Thu, 17 Jul 2025 17:04:22 +0800
Subject: [PATCH 03/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=20SyscallComma?=
 =?UTF-8?q?nd=20=E7=B1=BB=E5=AE=9E=E7=8E=B0=E7=B3=BB=E7=BB=9F=E8=B0=83?=
 =?UTF-8?q?=E7=94=A8=E5=8A=9F=E8=83=BD?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 新增 SyscallCommand 类，用于处理系统调用命令（opcode =0x0401）
---
 .../system/control/SyscallCommand.java        | 72 +++++++++++++++++++
 1 file changed, 72 insertions(+)
 create mode 100644 src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java

diff --git a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
new file mode 100644
index 0000000..017d561
--- /dev/null
+++ b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
@@ -0,0 +1,72 @@
+package org.jcnc.snow.vm.commands.system.control;
+
+import org.jcnc.snow.vm.interfaces.Command;
+import org.jcnc.snow.vm.module.CallStack;
+import org.jcnc.snow.vm.module.LocalVariableStore;
+import org.jcnc.snow.vm.module.OperandStack;
+
+import java.util.Arrays;
+
+/**
+ * SyscallCommand ―― 统一的系统调用入口（opcode = 0x0401）。
+ *
+ * <p>当前支持子命令：
+ * <ul>
+ *   <li><b>PRINT</b>   —— 打印，不换行</li>
+ *   <li><b>PRINTLN</b> —— 打印并换行</li>
+ * </ul>
+ *
+ * <p>用法示例（VM 指令）：</p>
+ * <pre>
+ *   1025 PRINT "Hello, Snow!"
+ *   I_PUSH 42
+ *   1025 PRINTLN
+ * </pre>
+ */
+public class SyscallCommand implements Command {
+
+    @Override
+    public int execute(String[] parts, int currentPC,
+                       OperandStack operandStack,
+                       LocalVariableStore localVariableStore,
+                       CallStack callStack) {
+
+        if (parts.length < 2)
+            throw new IllegalArgumentException("SYSCALL requires a sub-command");
+
+        String subCmd = parts[1].toUpperCase();
+
+        switch (subCmd) {
+            case "PRINT":
+            case "PRINTLN": {
+                boolean newline = subCmd.equals("PRINTLN");
+                String output;
+
+                // 指令里直接带字符串常量
+                if (parts.length > 2) {
+                    output = String.join(" ", Arrays.copyOfRange(parts, 2, parts.length));
+                    if (output.length() >= 2 &&
+                        output.startsWith("\"") &&
+                        output.endsWith("\"")) {
+                        output = output.substring(1, output.length() - 1); // 去掉首尾引号
+                    }
+                }
+                // 没带常量，则弹栈打印
+                else {
+                    Object value = operandStack.pop();
+                    output = String.valueOf(value);
+                }
+
+                if (newline) System.out.println(output);
+                else          System.out.print(output);
+                break;
+            }
+
+            default:
+                throw new UnsupportedOperationException("Unsupported SYSCALL: " + subCmd);
+        }
+
+        // 下一条指令
+        return currentPC + 1;
+    }
+}

From 59aef0c6616e8963e090444355c6393b62009213 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Thu, 17 Jul 2025 17:05:48 +0800
Subject: [PATCH 04/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=20SYSCALL=20?=
 =?UTF-8?q?=E6=93=8D=E4=BD=9C=E7=A0=81=E7=9A=84=E8=AF=A6=E7=BB=86=E6=B3=A8?=
 =?UTF-8?q?=E9=87=8A=E5=B9=B6=E7=A7=BB=E9=99=A4=E6=9C=AA=E4=BD=BF=E7=94=A8?=
 =?UTF-8?q?=E7=9A=84=20DEBUG=5FTRAP=20=E6=93=8D=E4=BD=9C=E7=A0=81?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 为 SYSCALL 操作码添加了详细的注释，说明了其执行步骤和实现类- 注释掉了未使用的 DEBUG_TRAP 操作码
- 引入了 SyscallCommand 类以实现 SYSCALL 操作码的功能
---
 src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java b/src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java
index 73d8ed5..8e1a880 100644
--- a/src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java
+++ b/src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java
@@ -1,5 +1,6 @@
 package org.jcnc.snow.vm.engine;
 
+import org.jcnc.snow.vm.commands.system.control.SyscallCommand;
 import org.jcnc.snow.vm.commands.type.control.byte8.*;
 import org.jcnc.snow.vm.commands.type.control.double64.*;
 import org.jcnc.snow.vm.commands.type.control.float32.*;
@@ -2646,8 +2647,18 @@ public class VMOpCode {
      * </ul>
      */
     public static final int HALT = 0x0400;
+    /**
+     * SYSCALL Opcode: Represents a system call operation that invokes a system-level function or service.
+     * <p>This opcode is implemented by the {@link SyscallCommand} class, which defines its specific execution logic.</p>
+     *
+     * <p>Execution Steps:</p>
+     * <ol>
+     *     <li>Parses the system call identifier from the instruction parameters.</li>
+     *     <li>Invokes the corresponding system-level function or service based on the system call identifier.</li>
+     *     <li>Returns the result of the system call operation.</li>
+     */
     public static final int SYSCALL = 0x0401;
-    public static final int DEBUG_TRAP = 0x0402;
+//    public static final int DEBUG_TRAP = 0x0402;
     // endregion
 
     /**

From 08cfc1ffb964d5563709e7c0f473f3a0602797d2 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Thu, 17 Jul 2025 17:06:39 +0800
Subject: [PATCH 05/36] =?UTF-8?q?test:=20=E4=BF=AE=E6=94=B9=20Bug1?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 playground/BugFarm/Bug1/Main.snow | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/playground/BugFarm/Bug1/Main.snow b/playground/BugFarm/Bug1/Main.snow
index f4fb369..3c4df88 100644
--- a/playground/BugFarm/Bug1/Main.snow
+++ b/playground/BugFarm/Bug1/Main.snow
@@ -2,8 +2,7 @@ module: Main
     function: main
         return_type: void
         body:
-            declare abc!:int =1
-
+            declare abc:string ="0"
         end body
     end function
 end module

From dad69eabfba04b799a28e5d2dac6357cb3865af5 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Fri, 18 Jul 2025 18:06:19 +0800
Subject: [PATCH 06/36] =?UTF-8?q?feat(vm):=20=E5=AE=9E=E7=8E=B0=20UNIX?=
 =?UTF-8?q?=E9=A3=8E=E6=A0=BC=E7=9A=84=E6=96=87=E4=BB=B6=E6=8F=8F=E8=BF=B0?=
 =?UTF-8?q?=E7=AC=A6=20I/O=20=E6=93=8D=E4=BD=9C?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 新增 FDTable 类，用于管理文件描述符和 NIO Channel 的映射
- 重构 SyscallCommand 类，实现多个 I/O 相关的 syscall 子命令
- 支持文件操作（open、close、read、write、seek）、管道、网络套接字、I/O 多路复用等功能
- 优化异常处理机制，统一处理 syscall内部异常
---
 .../system/control/SyscallCommand.java        | 400 ++++++++++++++++--
 .../java/org/jcnc/snow/vm/io/FDTable.java     |  62 +++
 2 files changed, 422 insertions(+), 40 deletions(-)
 create mode 100644 src/main/java/org/jcnc/snow/vm/io/FDTable.java

diff --git a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
index 017d561..b45754e 100644
--- a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
+++ b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
@@ -1,72 +1,392 @@
 package org.jcnc.snow.vm.commands.system.control;
 
 import org.jcnc.snow.vm.interfaces.Command;
+import org.jcnc.snow.vm.io.FDTable;
 import org.jcnc.snow.vm.module.CallStack;
 import org.jcnc.snow.vm.module.LocalVariableStore;
 import org.jcnc.snow.vm.module.OperandStack;
 
-import java.util.Arrays;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.*;
+import java.nio.file.OpenOption;
+import java.nio.file.Paths;
+import java.util.*;
+
+import static java.nio.file.StandardOpenOption.*;
 
 /**
- * SyscallCommand ―― 统一的系统调用入口（opcode = 0x0401）。
+ * {@code SyscallCommand} —— I/O syscall 子命令集合指令。
  *
- * <p>当前支持子命令：
+ * <p>
+ * 封装类 UNIX 文件描述符（File Descriptor, FD）操作、文件/网络 I/O、管道、fd 复制、多路复用（select）等系统调用能力，
+ * 基于 Java NIO 统一实现，供虚拟机指令集以 SYSCALL 形式扩展使用。
+ * </p>
+ *
+ * <b>栈操作约定：</b>
  * <ul>
- *   <li><b>PRINT</b>   —— 打印，不换行</li>
- *   <li><b>PRINTLN</b> —— 打印并换行</li>
+ *   <li>参数按“右值先入栈、左值后入栈”的顺序推入操作数栈，执行 {@code SYSCALL <SUBCMD>} 后出栈。</li>
+ *   <li>即：调用 SYSCALL OPEN path flags mode，入栈顺序为 path（先入）→ flags → mode（后入），出栈时 mode→flags→path 弹出。</li>
  * </ul>
  *
- * <p>用法示例（VM 指令）：</p>
- * <pre>
- *   1025 PRINT "Hello, Snow!"
- *   I_PUSH 42
- *   1025 PRINTLN
- * </pre>
+ * <b>返回值说明：</b>
+ * <ul>
+ *   <li>成功：压入正值（如 FD、实际数据、字节数、0 表示成功）。</li>
+ *   <li>失败：统一压入 -1，后续可扩展为 errno 机制。</li>
+ * </ul>
+ *
+ * <b>支持的子命令（部分）：</b>
+ * <ul>
+ *   <li>PRINT / PRINTLN —— 控制台输出（<b>TODO: 代码未实现</b>）</li>
+ *   <li>OPEN / CLOSE / READ / WRITE / SEEK —— 文件 I/O 操作</li>
+ *   <li>PIPE / DUP —— 管道和 FD 复制</li>
+ *   <li>SOCKET / CONNECT / BIND / LISTEN / ACCEPT —— 网络套接字</li>
+ *   <li>SELECT —— I/O 多路复用</li>
+ * </ul>
  */
 public class SyscallCommand implements Command {
 
+    /*------------------------------------ 工具方法 ------------------------------------*/
+
+    /**
+     * <b>POSIX open 标志到 Java NIO OpenOption 的映射</b>
+     * <p>
+     * 将 Linux/UNIX 的 open 调用 flags 参数，转换为 Java NIO 的 OpenOption 集合。
+     * 目前仅支持 WRITE（0x1）、READ、CREATE（0x40）、TRUNCATE（0x200）、APPEND（0x400）等常用标志。
+     * </p>
+     *
+     * @param flags POSIX 风格 open 标志（如 O_WRONLY=0x1, O_CREAT=0x40 等）
+     * @return 映射后的 OpenOption 集合
+     */
+    private static Set<OpenOption> flagsToOptions(int flags) {
+        Set<OpenOption> opts = new HashSet<>();
+        // 0x1 = WRITE，否则默认 READ
+        if ((flags & 0x1) != 0) opts.add(WRITE);
+        else opts.add(READ);
+        if ((flags & 0x40) != 0) opts.add(CREATE);
+        if ((flags & 0x200) != 0) opts.add(TRUNCATE_EXISTING);
+        if ((flags & 0x400) != 0) opts.add(APPEND);
+        return opts;
+    }
+
+    /**
+     * <b>统一异常处理</b>：
+     * <p>
+     * 捕获 syscall 内部所有异常，将 -1 压入操作数栈，表示系统调用失败（暂不区分错误类型）。
+     * 常见异常如文件不存在、权限不足、通道类型不符、网络故障等。
+     * </p>
+     *
+     * @param stack 当前操作数栈
+     * @param e 捕获的异常对象
+     */
+    private static void pushErr(OperandStack stack, Exception e) {
+        stack.push(-1);  // 目前统一用 -1，后续可按异常类型/errno 映射
+    }
+
+    /*--------------------------------------------------------------------------------*/
+
+    /**
+     * <b>执行 SYSCALL 子命令</b>：
+     * <p>
+     * 按照 parts[1] 指定的 SYSCALL 子命令，结合虚拟机栈与资源表完成对应的系统调用模拟。
+     * 支持基础文件、网络、管道等 I/O 操作，并对异常统一处理。
+     * </p>
+     *
+     * @param parts 指令字符串数组，parts[1] 为子命令
+     * @param pc 当前指令计数器
+     * @param stack 操作数栈
+     * @param locals 局部变量表
+     * @param callStack 调用栈
+     * @return 下一条指令的 pc 值（默认 pc+1）
+     */
     @Override
-    public int execute(String[] parts, int currentPC,
-                       OperandStack operandStack,
-                       LocalVariableStore localVariableStore,
+    public int execute(String[] parts, int pc,
+                       OperandStack stack,
+                       LocalVariableStore locals,
                        CallStack callStack) {
 
         if (parts.length < 2)
-            throw new IllegalArgumentException("SYSCALL requires a sub-command");
+            throw new IllegalArgumentException("SYSCALL needs sub-command");
 
-        String subCmd = parts[1].toUpperCase();
+        String cmd = parts[1].toUpperCase(Locale.ROOT);
 
-        switch (subCmd) {
-            case "PRINT":
-            case "PRINTLN": {
-                boolean newline = subCmd.equals("PRINTLN");
-                String output;
+        try {
+            switch (cmd) {
 
-                // 指令里直接带字符串常量
-                if (parts.length > 2) {
-                    output = String.join(" ", Arrays.copyOfRange(parts, 2, parts.length));
-                    if (output.length() >= 2 &&
-                        output.startsWith("\"") &&
-                        output.endsWith("\"")) {
-                        output = output.substring(1, output.length() - 1); // 去掉首尾引号
+                /*==================== 文件 / 目录 ====================*/
+
+                /*
+                 * OPEN —— 打开文件，返回文件描述符（File Descriptor, FD）。
+                 * 入栈（push）顺序: path（文件路径, String）, flags（int）, mode（int，文件权限，暂未用）
+                 * 出栈（pop）顺序: mode → flags → path
+                 * 成功返回 fd，失败返回 -1。
+                 */
+                case "OPEN" -> {
+                    int mode = (Integer) stack.pop();      // 目前未用
+                    int flags = (Integer) stack.pop();
+                    String path = String.valueOf(stack.pop());
+                    FileChannel fc = FileChannel.open(Paths.get(path), flagsToOptions(flags));
+                    stack.push(FDTable.register(fc));
+                }
+                /*
+                 * CLOSE —— 关闭文件描述符。
+                 * 入栈顺序: fd（int）
+                 * 出栈顺序: fd
+                 * 返回 0 成功，-1 失败
+                 */
+                case "CLOSE" -> {
+                    int fd = (Integer) stack.pop();
+                    FDTable.close(fd);
+                    stack.push(0);
+                }
+                /*
+                 * READ —— 从 fd 读取指定字节数。
+                 * 入栈顺序: fd（int）, count（int，字节数）
+                 * 出栈顺序: count → fd
+                 * 返回：byte[]（实际读取的数据，EOF 时长度为 0）
+                 */
+                case "READ" -> {
+                    int count = (Integer) stack.pop();
+                    int fd = (Integer) stack.pop();
+                    Channel ch = FDTable.get(fd);
+                    if (!(ch instanceof ReadableByteChannel rch)) {
+                        stack.push(new byte[0]);
+                        break;
                     }
+                    ByteBuffer buf = ByteBuffer.allocate(count);
+                    int n = rch.read(buf);
+                    if (n < 0) n = 0;
+                    buf.flip();
+                    byte[] out = new byte[n];
+                    buf.get(out);
+                    stack.push(out);
                 }
-                // 没带常量，则弹栈打印
-                else {
-                    Object value = operandStack.pop();
-                    output = String.valueOf(value);
+                /*
+                 * WRITE —— 向 fd 写数据。
+                 * 入栈顺序: fd（int）, data（byte[] 或 String）
+                 * 出栈顺序: data → fd
+                 * 返回写入字节数，失败 -1
+                 */
+                case "WRITE" -> {
+                    Object dataObj = stack.pop();
+                    int fd = (Integer) stack.pop();
+                    byte[] data = (dataObj instanceof byte[] b)
+                            ? b
+                            : String.valueOf(dataObj).getBytes();
+                    Channel ch = FDTable.get(fd);
+                    if (!(ch instanceof WritableByteChannel wch)) {
+                        stack.push(-1);
+                        break;
+                    }
+                    int written = wch.write(ByteBuffer.wrap(data));
+                    stack.push(written);
+                }
+                /*
+                 * SEEK —— 文件定位，移动文件读写指针。
+                 * 入栈顺序: fd（int）, offset（long/int）, whence（int, 0=SET,1=CUR,2=END）
+                 * 出栈顺序: whence → offset → fd
+                 * 返回新位置（long），失败 -1
+                 */
+                case "SEEK" -> {
+                    int whence = (Integer) stack.pop();
+                    long off = ((Number) stack.pop()).longValue();
+                    int fd = (Integer) stack.pop();
+                    Channel ch = FDTable.get(fd);
+                    if (!(ch instanceof SeekableByteChannel sbc)) {
+                        stack.push(-1);
+                        break;
+                    }
+                    SeekableByteChannel newPos = switch (whence) {
+                        case 0 -> sbc.position(off);
+                        case 1 -> sbc.position(sbc.position() + off);
+                        case 2 -> sbc.position(sbc.size() + off);
+                        default -> throw new IllegalArgumentException("bad whence");
+                    };
+                    stack.push(newPos);
                 }
 
-                if (newline) System.out.println(output);
-                else          System.out.print(output);
-                break;
+                /*==================== 管道 / FD 相关 ====================*/
+
+                /*
+                 * PIPE —— 创建匿名管道。
+                 * 入栈顺序: （无）
+                 * 出栈顺序: （无）
+                 * 返回顺序: write fd（先压栈），read fd（后压栈）
+                 */
+                case "PIPE" -> {
+                    Pipe p = Pipe.open();
+                    stack.push(FDTable.register(p.sink()));   // write fd
+                    stack.push(FDTable.register(p.source())); // read fd
+                }
+                /*
+                 * DUP —— 复制一个已存在的 fd（dup）。
+                 * 入栈顺序: oldfd（int）
+                 * 出栈顺序: oldfd
+                 * 返回新的 fd，失败 -1
+                 */
+                case "DUP" -> {
+                    int oldfd = (Integer) stack.pop();
+                    stack.push(FDTable.dup(oldfd));
+                }
+
+                /*==================== 网络相关 ====================*/
+
+                /*
+                 * SOCKET —— 创建套接字，支持 stream/dgram。
+                 * 入栈顺序: domain（int, AF_INET=2等）, type（int, 1=STREAM,2=DGRAM）, protocol（int, 预留）
+                 * 出栈顺序: protocol → type → domain
+                 * 返回 fd
+                 */
+                case "SOCKET" -> {
+                    int proto = (Integer) stack.pop();      // 预留，暂不用
+                    int type = (Integer) stack.pop();       // 1=STREAM,2=DGRAM
+                    int domain = (Integer) stack.pop();     // AF_INET=2……
+                    Channel ch = (type == 1)
+                            ? SocketChannel.open()
+                            : DatagramChannel.open();
+                    stack.push(FDTable.register(ch));
+                }
+                /*
+                 * CONNECT —— 发起 TCP 连接。
+                 * 入栈顺序: fd（int）, host（String）, port（int）
+                 * 出栈顺序: port → host → fd
+                 * 返回 0 成功，-1 失败
+                 */
+                case "CONNECT" -> {
+                    int port = (Integer) stack.pop();
+                    String host = String.valueOf(stack.pop());
+                    int fd = (Integer) stack.pop();
+                    Channel ch = FDTable.get(fd);
+                    if (ch instanceof SocketChannel sc) {
+                        sc.connect(new InetSocketAddress(host, port));
+                        stack.push(0);
+                    } else stack.push(-1);
+                }
+                /*
+                 * BIND —— 绑定端口。
+                 * 入栈顺序: fd（int）, host（String）, port（int）
+                 * 出栈顺序: port → host → fd
+                 * 返回 0 成功，-1 失败
+                 */
+                case "BIND" -> {
+                    int port = (Integer) stack.pop();
+                    String host = String.valueOf(stack.pop());
+                    int fd = (Integer) stack.pop();
+                    Channel ch = FDTable.get(fd);
+                    if (ch instanceof ServerSocketChannel ssc) {
+                        ssc.bind(new InetSocketAddress(host, port));
+                        stack.push(0);
+                    } else stack.push(-1);
+                }
+                /*
+                 * LISTEN —— 监听 socket，兼容 backlog。
+                 * 入栈顺序: fd（int）, backlog（int）
+                 * 出栈顺序: backlog → fd
+                 * 返回 0 成功，-1 失败
+                 * <b>注意：Java NIO 打开 ServerSocketChannel 已自动监听，无 backlog 处理，行为和 UNIX 有区别。</b>
+                 */
+                case "LISTEN" -> {
+                    int backlog = (Integer) stack.pop();
+                    int fd = (Integer) stack.pop();
+                    Channel ch = FDTable.get(fd);
+                    if (ch instanceof ServerSocketChannel) stack.push(0);
+                    else stack.push(-1);
+                }
+                /*
+                 * ACCEPT —— 接收连接。
+                 * 入栈顺序: fd（int）
+                 * 出栈顺序: fd
+                 * 返回新连接 fd，失败 -1
+                 */
+                case "ACCEPT" -> {
+                    int fd = (Integer) stack.pop();
+                    Channel ch = FDTable.get(fd);
+                    if (ch instanceof ServerSocketChannel ssc) {
+                        SocketChannel cli = ssc.accept();
+                        stack.push(FDTable.register(cli));
+                    } else stack.push(-1);
+                }
+
+                /*==================== 多路复用 ====================*/
+
+                /*
+                 * SELECT —— I/O 多路复用，监视多个 fd 是否可读写。
+                 * 入栈顺序: fds（List<Integer>）, timeout_ms（long）
+                 * 出栈顺序: timeout_ms → fds
+                 * 返回: 就绪 fd 列表（List<Integer>）
+                 */
+                case "SELECT" -> {
+                    long timeout = ((Number) stack.pop()).longValue();
+                    @SuppressWarnings("unchecked")
+                    List<Integer> fds = (List<Integer>) stack.pop();
+
+                    Selector sel = Selector.open();
+                    for (int fd : fds) {
+                        Channel c = FDTable.get(fd);
+                        if (c instanceof SelectableChannel sc) {
+                            sc.configureBlocking(false);
+                            int ops = (c instanceof ReadableByteChannel ? SelectionKey.OP_READ : 0)
+                                    | (c instanceof WritableByteChannel ? SelectionKey.OP_WRITE : 0);
+                            sc.register(sel, ops, fd);
+                        }
+                    }
+                    int ready = sel.select(timeout);
+                    List<Integer> readyFds = new ArrayList<>();
+                    if (ready > 0) {
+                        for (SelectionKey k : sel.selectedKeys())
+                            readyFds.add((Integer) k.attachment());
+                    }
+                    stack.push(readyFds);
+                    sel.close();
+                }
+
+
+                /*==================== 控制台输出 ====================*/
+
+                /*
+                 * PRINT —— 控制台输出（无换行）。
+                 * 入栈顺序: data（String 或 byte[]）
+                 * 出栈顺序: data
+                 * 返回 0
+                 */
+                case "PRINT" -> {
+                    Object dataObj = stack.pop();
+                    if (dataObj instanceof byte[] b) {
+                        System.out.print(new String(b));
+                    } else {
+                        System.out.print(dataObj);
+                    }
+                    stack.push(0); // 表示成功
+                }
+                /*
+                 * PRINTLN —— 控制台输出（自动换行）。
+                 * 入栈顺序: data（String 或 byte[]）
+                 * 出栈顺序: data
+                 * 返回 0
+                 */
+                case "PRINTLN" -> {
+                    Object dataObj = stack.pop();
+                    if (dataObj instanceof byte[] b) {
+                        System.out.println(new String(b));
+                    } else {
+                        System.out.println(dataObj);
+                    }
+                    stack.push(0); // 表示成功
+                }
+
+                /*==================== 其它未实现/扩展命令 ====================*/
+
+                /*
+                 * TODO: PRINT / PRINTLN / 其它自定义 syscall 子命令未实现
+                 */
+                default -> throw new UnsupportedOperationException("Unsupported SYSCALL: " + cmd);
             }
-
-            default:
-                throw new UnsupportedOperationException("Unsupported SYSCALL: " + subCmd);
+        } catch (Exception e) {
+            // 统一异常处理，异常时压入 -1
+            pushErr(stack, e);
         }
 
-        // 下一条指令
-        return currentPC + 1;
+        // 默认：下一条指令
+        return pc + 1;
     }
 }
diff --git a/src/main/java/org/jcnc/snow/vm/io/FDTable.java b/src/main/java/org/jcnc/snow/vm/io/FDTable.java
new file mode 100644
index 0000000..98d6385
--- /dev/null
+++ b/src/main/java/org/jcnc/snow/vm/io/FDTable.java
@@ -0,0 +1,62 @@
+package org.jcnc.snow.vm.io;
+
+import java.io.BufferedInputStream;
+import java.io.BufferedOutputStream;
+import java.io.IOException;
+import java.nio.channels.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * 维护 “虚拟 fd → Java NIO Channel” 的全局映射表。
+ *
+ * <pre>
+ *   0  → stdin   (ReadableByteChannel)
+ *   1  → stdout  (WritableByteChannel)
+ *   2  → stderr  (WritableByteChannel)
+ *   3+ → 运行期动态分配
+ * </pre>
+ */
+public final class FDTable {
+
+    private FDTable() {}
+
+    /** 下一次可用 fd（0‒2 保留给标准流） */
+    private static final AtomicInteger NEXT_FD = new AtomicInteger(3);
+    /** 主映射表：fd → Channel */
+    private static final ConcurrentHashMap<Integer, Channel> MAP = new ConcurrentHashMap<>();
+
+    static {
+        // JVM 标准流包装成 NIO Channel 后放入表中
+        MAP.put(0, Channels.newChannel(new BufferedInputStream(System.in)));
+        MAP.put(1, Channels.newChannel(new BufferedOutputStream(System.out)));
+        MAP.put(2, Channels.newChannel(new BufferedOutputStream(System.err)));
+    }
+
+    /** 注册新 Channel，返回分配到的虚拟 fd */
+    public static int register(Channel ch) {
+        int fd = NEXT_FD.getAndIncrement();
+        MAP.put(fd, ch);
+        return fd;
+    }
+
+    /** 取得 Channel；如果 fd 不存在则返回 null */
+    public static Channel get(int fd) {
+        return MAP.get(fd);
+    }
+
+    /** 关闭并移除 fd（0‒2 忽略） */
+    public static void close(int fd) throws IOException {
+        if (fd <= 2) return;                                   // 标准流交由宿主 JVM 维护
+        Channel ch = MAP.remove(fd);
+        if (ch != null && ch.isOpen()) ch.close();
+    }
+
+    /** 类似 dup(oldfd) —— 返回指向同一 Channel 的新 fd */
+    public static int dup(int oldfd) {
+        Channel ch = MAP.get(oldfd);
+        if (ch == null)
+            throw new IllegalArgumentException("Bad fd: " + oldfd);
+        return register(ch);                                   // 多个 fd 引用同一 Channel
+    }
+}

From 8ec5120e544cb6e1632000c7614fbbf6892bf953 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Fri, 18 Jul 2025 23:33:13 +0800
Subject: [PATCH 07/36] =?UTF-8?q?docs:=20=E6=9B=B4=E6=96=B0=E5=AD=90?=
 =?UTF-8?q?=E5=91=BD=E4=BB=A4=E6=94=AF=E6=8C=81=E7=8A=B6=E6=80=81?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 移除 PRINT / PRINTLN 命令的 TODO 注释
- 修正其它自定义 syscall 子命令的 TODO 注释
---
 .../jcnc/snow/vm/commands/system/control/SyscallCommand.java  | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
index b45754e..39e63e7 100644
--- a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
+++ b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
@@ -37,7 +37,7 @@ import static java.nio.file.StandardOpenOption.*;
  *
  * <b>支持的子命令（部分）：</b>
  * <ul>
- *   <li>PRINT / PRINTLN —— 控制台输出（<b>TODO: 代码未实现</b>）</li>
+ *   <li>PRINT / PRINTLN —— 控制台输出</li>
  *   <li>OPEN / CLOSE / READ / WRITE / SEEK —— 文件 I/O 操作</li>
  *   <li>PIPE / DUP —— 管道和 FD 复制</li>
  *   <li>SOCKET / CONNECT / BIND / LISTEN / ACCEPT —— 网络套接字</li>
@@ -377,7 +377,7 @@ public class SyscallCommand implements Command {
                 /*==================== 其它未实现/扩展命令 ====================*/
 
                 /*
-                 * TODO: PRINT / PRINTLN / 其它自定义 syscall 子命令未实现
+                 * 其它自定义 syscall 子命令未实现
                  */
                 default -> throw new UnsupportedOperationException("Unsupported SYSCALL: " + cmd);
             }

From 4e3de185b83f795cbfe61f1d23bc3fc732081927 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Sat, 19 Jul 2025 00:09:17 +0800
Subject: [PATCH 08/36] =?UTF-8?q?refactor:=E9=87=8D=E6=9E=84=20PRINT=20?=
 =?UTF-8?q?=E5=92=8C=20PRINTLN=20=E5=8A=9F=E8=83=BD=E5=B9=B6=E4=BC=98?=
 =?UTF-8?q?=E5=8C=96=E8=BE=93=E5=87=BA=E6=96=B9=E6=B3=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 重构了 PRINT 和 PRINTLN 指令的实现，支持更多数据类型输出
- 新增通用的 output辅助方法，统一处理各种类型的输出
- 扩展了输出功能，支持基本类型、数组和任意对象的打印
- 优化了代码结构，提高了可读性和可维护性
---
 .../system/control/SyscallCommand.java        | 149 +++++++++++-------
 1 file changed, 91 insertions(+), 58 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
index 39e63e7..eebcd28 100644
--- a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
+++ b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
@@ -46,42 +46,7 @@ import static java.nio.file.StandardOpenOption.*;
  */
 public class SyscallCommand implements Command {
 
-    /*------------------------------------ 工具方法 ------------------------------------*/
 
-    /**
-     * <b>POSIX open 标志到 Java NIO OpenOption 的映射</b>
-     * <p>
-     * 将 Linux/UNIX 的 open 调用 flags 参数，转换为 Java NIO 的 OpenOption 集合。
-     * 目前仅支持 WRITE（0x1）、READ、CREATE（0x40）、TRUNCATE（0x200）、APPEND（0x400）等常用标志。
-     * </p>
-     *
-     * @param flags POSIX 风格 open 标志（如 O_WRONLY=0x1, O_CREAT=0x40 等）
-     * @return 映射后的 OpenOption 集合
-     */
-    private static Set<OpenOption> flagsToOptions(int flags) {
-        Set<OpenOption> opts = new HashSet<>();
-        // 0x1 = WRITE，否则默认 READ
-        if ((flags & 0x1) != 0) opts.add(WRITE);
-        else opts.add(READ);
-        if ((flags & 0x40) != 0) opts.add(CREATE);
-        if ((flags & 0x200) != 0) opts.add(TRUNCATE_EXISTING);
-        if ((flags & 0x400) != 0) opts.add(APPEND);
-        return opts;
-    }
-
-    /**
-     * <b>统一异常处理</b>：
-     * <p>
-     * 捕获 syscall 内部所有异常，将 -1 压入操作数栈，表示系统调用失败（暂不区分错误类型）。
-     * 常见异常如文件不存在、权限不足、通道类型不符、网络故障等。
-     * </p>
-     *
-     * @param stack 当前操作数栈
-     * @param e 捕获的异常对象
-     */
-    private static void pushErr(OperandStack stack, Exception e) {
-        stack.push(-1);  // 目前统一用 -1，后续可按异常类型/errno 映射
-    }
 
     /*--------------------------------------------------------------------------------*/
 
@@ -92,10 +57,10 @@ public class SyscallCommand implements Command {
      * 支持基础文件、网络、管道等 I/O 操作，并对异常统一处理。
      * </p>
      *
-     * @param parts 指令字符串数组，parts[1] 为子命令
-     * @param pc 当前指令计数器
-     * @param stack 操作数栈
-     * @param locals 局部变量表
+     * @param parts     指令字符串数组，parts[1] 为子命令
+     * @param pc        当前指令计数器
+     * @param stack     操作数栈
+     * @param locals    局部变量表
      * @param callStack 调用栈
      * @return 下一条指令的 pc 值（默认 pc+1）
      */
@@ -345,35 +310,24 @@ public class SyscallCommand implements Command {
 
                 /*
                  * PRINT —— 控制台输出（无换行）。
-                 * 入栈顺序: data（String 或 byte[]）
+                 * 入栈顺序: data（任意基本类型或其包装类型、String、byte[] 等）
                  * 出栈顺序: data
                  * 返回 0
                  */
                 case "PRINT" -> {
                     Object dataObj = stack.pop();
-                    if (dataObj instanceof byte[] b) {
-                        System.out.print(new String(b));
-                    } else {
-                        System.out.print(dataObj);
-                    }
-                    stack.push(0); // 表示成功
+                    output(dataObj, false);
+                    stack.push(0); // success
                 }
-                /*
-                 * PRINTLN —— 控制台输出（自动换行）。
-                 * 入栈顺序: data（String 或 byte[]）
-                 * 出栈顺序: data
-                 * 返回 0
-                 */
+
+                /* PRINTLN —— 控制台输出（自动换行）。*/
                 case "PRINTLN" -> {
                     Object dataObj = stack.pop();
-                    if (dataObj instanceof byte[] b) {
-                        System.out.println(new String(b));
-                    } else {
-                        System.out.println(dataObj);
-                    }
-                    stack.push(0); // 表示成功
+                    output(dataObj, true);
+                    stack.push(0); // success
                 }
 
+
                 /*==================== 其它未实现/扩展命令 ====================*/
 
                 /*
@@ -389,4 +343,83 @@ public class SyscallCommand implements Command {
         // 默认：下一条指令
         return pc + 1;
     }
+
+    /*------------------------------------ 工具方法 ------------------------------------*/
+
+    /**
+     * <b>POSIX open 标志到 Java NIO OpenOption 的映射</b>
+     * <p>
+     * 将 Linux/UNIX 的 open 调用 flags 参数，转换为 Java NIO 的 OpenOption 集合。
+     * 目前仅支持 WRITE（0x1）、READ、CREATE（0x40）、TRUNCATE（0x200）、APPEND（0x400）等常用标志。
+     * </p>
+     *
+     * @param flags POSIX 风格 open 标志（如 O_WRONLY=0x1, O_CREAT=0x40 等）
+     * @return 映射后的 OpenOption 集合
+     */
+    private static Set<OpenOption> flagsToOptions(int flags) {
+        Set<OpenOption> opts = new HashSet<>();
+        // 0x1 = WRITE，否则默认 READ
+        if ((flags & 0x1) != 0) opts.add(WRITE);
+        else opts.add(READ);
+        if ((flags & 0x40) != 0) opts.add(CREATE);
+        if ((flags & 0x200) != 0) opts.add(TRUNCATE_EXISTING);
+        if ((flags & 0x400) != 0) opts.add(APPEND);
+        return opts;
+    }
+
+    /**
+     * <b>统一异常处理</b>：
+     * <p>
+     * 捕获 syscall 内部所有异常，将 -1 压入操作数栈，表示系统调用失败（暂不区分错误类型）。
+     * 常见异常如文件不存在、权限不足、通道类型不符、网络故障等。
+     * </p>
+     *
+     * @param stack 当前操作数栈
+     * @param e     捕获的异常对象
+     */
+    private static void pushErr(OperandStack stack, Exception e) {
+        stack.push(-1);  // 目前统一用 -1，后续可按异常类型/errno 映射
+    }
+
+    /**
+     * 统一的控制台输出辅助方法，支持：
+     * <ul>
+     *   <li>所有基本类型及其包装类（int、double、long、float…）</li>
+     *   <li>String、byte[]、char[] 以及其他原生数组</li>
+     *   <li>任意 Object（调用 {@code toString}）</li>
+     * </ul>
+     *
+     * @param obj     要输出的对象
+     * @param newline 是否追加换行
+     */
+    private static void output(Object obj, boolean newline) {
+        String str;
+        if (obj == null) {
+            str = "null";
+        } else if (obj instanceof byte[] bytes) {
+            str = new String(bytes);
+        } else if (obj.getClass().isArray()) {
+            str = arrayToString(obj);
+        } else {
+            str = obj.toString();
+        }
+        if (newline) System.out.println(str);
+        else System.out.print(str);
+    }
+
+    /**
+     * 将各种原生数组转换成可读字符串。
+     */
+    private static String arrayToString(Object array) {
+        if (array instanceof int[] a) return Arrays.toString(a);
+        if (array instanceof long[] a) return Arrays.toString(a);
+        if (array instanceof double[] a) return Arrays.toString(a);
+        if (array instanceof float[] a) return Arrays.toString(a);
+        if (array instanceof short[] a) return Arrays.toString(a);
+        if (array instanceof char[] a) return Arrays.toString(a);
+        if (array instanceof byte[] a) return Arrays.toString(a);
+        if (array instanceof boolean[] a) return Arrays.toString(a);
+        if (array instanceof Object[] a) return Arrays.deepToString(a);
+        return "Unsupported array";
+    }
 }

From 64cefebee542f7ae263ca1896363a6ae143f8a36 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Sat, 19 Jul 2025 17:04:49 +0800
Subject: [PATCH 09/36] =?UTF-8?q?feat:=20=E5=AE=9E=E7=8E=B0=20BuiltinUtils?=
 =?UTF-8?q?=20=E6=A0=87=E5=87=86=E5=BA=93=E5=B9=B6=E6=9B=B4=E6=96=B0?=
 =?UTF-8?q?=E7=9B=B8=E5=85=B3=E6=9C=BA=E5=88=B6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 重构 BuiltinTypeRegistry 类，扩展内置类型和模块的注册功能
- 新增 BuiltinUtils 标准库模块，提供 print 和 println 函数
- 实现 syscall 内核函数，供 BuiltinUtils 内部使用
- 更新测试用例，添加 Demo14 项目以验证新功能
---
 .run/测试.run.xml                             |  1 -
 playground/Demo/Demo14/BuiltinUtils.snow      | 19 ++++
 playground/Demo/Demo14/Main.snow              | 11 +++
 .../semantic/core/BuiltinTypeRegistry.java    | 90 +++++++++++--------
 4 files changed, 85 insertions(+), 36 deletions(-)
 create mode 100644 playground/Demo/Demo14/BuiltinUtils.snow
 create mode 100644 playground/Demo/Demo14/Main.snow

diff --git a/.run/测试.run.xml b/.run/测试.run.xml
index 5000363..c37e7f3 100644
--- a/.run/测试.run.xml
+++ b/.run/测试.run.xml
@@ -3,7 +3,6 @@
     <toRun name="Demo1" type="Application" />
     <toRun name="Demo10" type="Application" />
     <toRun name="Demo11" type="Application" />
-    <toRun name="Demo11" type="Application" />
     <toRun name="Demo12" type="Application" />
     <toRun name="Demo13" type="Application" />
     <toRun name="Demo2" type="Application" />
diff --git a/playground/Demo/Demo14/BuiltinUtils.snow b/playground/Demo/Demo14/BuiltinUtils.snow
new file mode 100644
index 0000000..d915ee8
--- /dev/null
+++ b/playground/Demo/Demo14/BuiltinUtils.snow
@@ -0,0 +1,19 @@
+module: BuiltinUtils
+  function: print
+    parameter:
+      declare msg: int
+    return_type: void
+    body:
+      syscall("PRINT",1)
+    end body
+  end function
+
+  function: println
+    parameter:
+      declare msg: int
+    return_type: void
+    body:
+      syscall("PRINTLN",1)
+    end body
+  end function
+end module
diff --git a/playground/Demo/Demo14/Main.snow b/playground/Demo/Demo14/Main.snow
new file mode 100644
index 0000000..baf23e4
--- /dev/null
+++ b/playground/Demo/Demo14/Main.snow
@@ -0,0 +1,11 @@
+module: Main
+  import: BuiltinUtils
+
+  function: main
+    return_type: void
+    body:
+      BuiltinUtils.print(1)
+      BuiltinUtils.println(2)
+    end body
+  end function
+end module
\ No newline at end of file
diff --git a/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java b/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
index d1566ab..3e69f38 100644
--- a/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
+++ b/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
@@ -1,54 +1,74 @@
 package org.jcnc.snow.compiler.semantic.core;
 
-import org.jcnc.snow.compiler.semantic.type.*;
+import org.jcnc.snow.compiler.semantic.type.BuiltinType;
+import org.jcnc.snow.compiler.semantic.type.FunctionType;
+import org.jcnc.snow.compiler.semantic.type.Type;
 
-import java.util.Map;
+import java.util.*;
 
 /**
- * {@code BuiltinTypeRegistry} 是内置类型和内置模块的集中注册中心。
- * <p>
- * 本类主要负责: 
+ * 语言全部内置类型 / 模块 / 函数的注册中心。
+ *
+ * <p>目前同时注册：</p>
  * <ul>
- *   <li>定义语言中所有可识别的基础类型（如 int、float、string 等）；</li>
- *   <li>在语义分析初始化时，将内置模块（如 {@code BuiltinUtils}）注册到上下文中；</li>
- *   <li>提供对内置类型的快速查找支持。</li>
+ *   <li>所有基础类型（byte、short、int …）</li>
+ *   <li>标准库模块 <b>BuiltinUtils</b> —— 仅声明函数签名，真正实现写在 Snow 源码中</li>
+ *   <li>运行时内核函数 <b>syscall</b> —— 供标准库内部实现调用</li>
  * </ul>
- * 该类为纯工具类，所有成员均为静态，不可实例化。
  */
 public final class BuiltinTypeRegistry {
 
-    /**
-     * 内置类型映射表: 将类型名称字符串映射到对应的 {@link Type} 实例。
-     * <p>
-     * 用于类型解析过程（如解析变量声明或函数返回类型）中，
-     * 将用户源码中的类型字符串转换为语义类型对象。
-     */
-    public static final Map<String, Type> BUILTIN_TYPES = Map.of(
-            "int",    BuiltinType.INT,
-            "long",   BuiltinType.LONG,
-            "short",  BuiltinType.SHORT,
-            "byte",   BuiltinType.BYTE,
-            "float",  BuiltinType.FLOAT,
-            "double", BuiltinType.DOUBLE,
-            "string", BuiltinType.STRING,
-            "boolean", BuiltinType.BOOLEAN,
-            "void",   BuiltinType.VOID
-    );
+    /** 基础类型表：名称 → Type */
+    public static final Map<String, Type> BUILTIN_TYPES;
+    static {
+        Map<String, Type> t = new HashMap<>();
+        t.put("byte",   BuiltinType.BYTE);
+        t.put("short",  BuiltinType.SHORT);
+        t.put("int",    BuiltinType.INT);
+        t.put("long",   BuiltinType.LONG);
+        t.put("float",  BuiltinType.FLOAT);
+        t.put("double", BuiltinType.DOUBLE);
+        t.put("string", BuiltinType.STRING);
+        t.put("void",   BuiltinType.VOID);
+        BUILTIN_TYPES = Collections.unmodifiableMap(t);
+    }
 
-    /**
-     * 私有构造函数，禁止实例化。
-     */
     private BuiltinTypeRegistry() { }
 
     /**
-     * 初始化语义上下文中与内置模块相关的内容。
-     * <p>
-     * 当前实现将内置模块 {@code BuiltinUtils} 注册至上下文模块表中，
-     * 使其在用户代码中可被访问（如 {@code BuiltinUtils.to_string(...)}）。
-     *
-     * @param ctx 当前语义分析上下文
+     * 供语义分析阶段调用：向上下文注入所有内置模块 / 函数声明。
      */
     public static void init(Context ctx) {
+        /* ---------- BuiltinUtils ---------- */
+        ModuleInfo utils = new ModuleInfo("BuiltinUtils");
 
+        // print(string): void
+        utils.getFunctions().put(
+                "print",
+                new FunctionType(
+                        Collections.singletonList(BuiltinType.STRING),
+                        BuiltinType.VOID
+                )
+        );
+
+        // println(string): void
+        utils.getFunctions().put(
+                "println",
+                new FunctionType(
+                        Collections.singletonList(BuiltinType.STRING),
+                        BuiltinType.VOID
+                )
+        );
+
+        // syscall(string, string): void   —— 供 BuiltinUtils 内部使用
+        utils.getFunctions().put(
+                "syscall",
+                new FunctionType(
+                        Arrays.asList(BuiltinType.STRING, BuiltinType.STRING),
+                        BuiltinType.VOID
+                )
+        );
+
+        ctx.getModules().putIfAbsent("BuiltinUtils", utils);
     }
 }

From 72982c112751911cb9250257efe31d2d98ec254e Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Sun, 20 Jul 2025 18:48:54 +0800
Subject: [PATCH 10/36] =?UTF-8?q?chore:=20=E6=B7=BB=E5=8A=A0=20Demo14?=
 =?UTF-8?q?=E8=BF=90=E8=A1=8C=E9=85=8D=E7=BD=AE?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .run/Demo14.run.xml | 10 ++++++++++
 1 file changed, 10 insertions(+)
 create mode 100644 .run/Demo14.run.xml

diff --git a/.run/Demo14.run.xml b/.run/Demo14.run.xml
new file mode 100644
index 0000000..6071504
--- /dev/null
+++ b/.run/Demo14.run.xml
@@ -0,0 +1,10 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="Demo14" type="Application" factoryName="Application" folderName="Demo">
+    <option name="MAIN_CLASS_NAME" value="org.jcnc.snow.cli.SnowCLI" />
+    <module name="Snow" />
+    <option name="PROGRAM_PARAMETERS" value="compile run -d playground/Demo/Demo14 -o target/Demo14" />
+    <method v="2">
+      <option name="Make" enabled="true" />
+    </method>
+  </configuration>
+</component>
\ No newline at end of file

From 983a287c422c9282d4d77fd8c4296759c06e5c7f Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Sun, 20 Jul 2025 20:14:12 +0800
Subject: [PATCH 11/36] =?UTF-8?q?refactor:=20=E6=9B=B4=E6=96=B0=20BuiltinU?=
 =?UTF-8?q?tils=20=E4=B8=AD=20syscall=20=E5=87=BD=E6=95=B0=E7=9A=84?=
 =?UTF-8?q?=E5=8F=82=E6=95=B0=E7=B1=BB=E5=9E=8B?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 移除了 BuiltinUtils 中的 print 和 println函数
- 将 syscall 函数的第二个参数类型从 STRING 改为 INT
---
 .../semantic/core/BuiltinTypeRegistry.java    | 22 ++-----------------
 1 file changed, 2 insertions(+), 20 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java b/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
index 3e69f38..e4bba8e 100644
--- a/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
+++ b/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
@@ -42,29 +42,11 @@ public final class BuiltinTypeRegistry {
         /* ---------- BuiltinUtils ---------- */
         ModuleInfo utils = new ModuleInfo("BuiltinUtils");
 
-        // print(string): void
-        utils.getFunctions().put(
-                "print",
-                new FunctionType(
-                        Collections.singletonList(BuiltinType.STRING),
-                        BuiltinType.VOID
-                )
-        );
-
-        // println(string): void
-        utils.getFunctions().put(
-                "println",
-                new FunctionType(
-                        Collections.singletonList(BuiltinType.STRING),
-                        BuiltinType.VOID
-                )
-        );
-
-        // syscall(string, string): void   —— 供 BuiltinUtils 内部使用
+        // syscall(string, int): void   —— 供 BuiltinUtils 内部使用
         utils.getFunctions().put(
                 "syscall",
                 new FunctionType(
-                        Arrays.asList(BuiltinType.STRING, BuiltinType.STRING),
+                        Arrays.asList(BuiltinType.STRING, BuiltinType.INT),
                         BuiltinType.VOID
                 )
         );

From b332c76ef88d8353569e776cdc5ed6d66d3893da Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Sun, 20 Jul 2025 20:14:52 +0800
Subject: [PATCH 12/36] =?UTF-8?q?feat:=20=E5=A2=9E=E5=8A=A0=E8=87=AA?=
 =?UTF-8?q?=E5=8A=A8=E5=AF=BC=E5=85=A5=E6=A8=A1=E5=9D=97=E5=87=BD=E6=95=B0?=
 =?UTF-8?q?=E8=B0=83=E7=94=A8=E6=94=AF=E6=8C=81=20-=20=E5=AE=9E=E7=8E=B0?=
 =?UTF-8?q?=E4=BA=86=E5=9C=A8=E5=BD=93=E5=89=8D=E6=A8=A1=E5=9D=97=E6=9C=AA?=
 =?UTF-8?q?=E6=89=BE=E5=88=B0=E7=9B=AE=E6=A0=87=E5=87=BD=E6=95=B0=E6=97=B6?=
 =?UTF-8?q?=EF=BC=8C=E8=87=AA=E5=8A=A8=E9=81=8D=E5=8E=86=E6=89=80=E6=9C=89?=
 =?UTF-8?q?=E5=B7=B2=E5=AF=BC=E5=85=A5=E6=A8=A1=E5=9D=97=E5=AF=BB=E6=89=BE?=
 =?UTF-8?q?=E5=94=AF=E4=B8=80=E5=90=8C=E5=90=8D=E5=87=BD=E6=95=B0=E7=9A=84?=
 =?UTF-8?q?=E5=8A=9F=E8=83=BD=20-=20=E5=A6=82=E6=9E=9C=E5=A4=9A=E4=B8=AA?=
 =?UTF-8?q?=E5=AF=BC=E5=85=A5=E6=A8=A1=E5=9D=97=E5=90=AB=E6=9C=89=E5=90=8C?=
 =?UTF-8?q?=E5=90=8D=E5=87=BD=E6=95=B0=EF=BC=8C=E4=BC=9A=E6=8A=A5=E9=94=99?=
 =?UTF-8?q?=E6=8F=90=E7=A4=BA=E5=87=BD=E6=95=B0=E8=B0=83=E7=94=A8=E4=B8=8D?=
 =?UTF-8?q?=E6=98=8E=E7=A1=AE=20-=20=E8=BF=99=E4=B8=AA=E6=94=B9=E5=8A=A8?=
 =?UTF-8?q?=E6=89=A9=E5=B1=95=E4=BA=86=E5=87=BD=E6=95=B0=E8=B0=83=E7=94=A8?=
 =?UTF-8?q?=E7=9A=84=E8=8C=83=E5=9B=B4=EF=BC=8C=E6=8F=90=E9=AB=98=E4=BA=86?=
 =?UTF-8?q?=E4=BB=A3=E7=A0=81=E7=9A=84=E7=81=B5=E6=B4=BB=E6=80=A7=E5=92=8C?=
 =?UTF-8?q?=E5=8F=AF=E5=A4=8D=E7=94=A8=E6=80=A7?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 playground/Demo/Demo14/BuiltinUtils.snow      | 19 -----------
 .../expression/CallExpressionAnalyzer.java    | 34 +++++++++++++++++--
 2 files changed, 32 insertions(+), 21 deletions(-)
 delete mode 100644 playground/Demo/Demo14/BuiltinUtils.snow

diff --git a/playground/Demo/Demo14/BuiltinUtils.snow b/playground/Demo/Demo14/BuiltinUtils.snow
deleted file mode 100644
index d915ee8..0000000
--- a/playground/Demo/Demo14/BuiltinUtils.snow
+++ /dev/null
@@ -1,19 +0,0 @@
-module: BuiltinUtils
-  function: print
-    parameter:
-      declare msg: int
-    return_type: void
-    body:
-      syscall("PRINT",1)
-    end body
-  end function
-
-  function: println
-    parameter:
-      declare msg: int
-    return_type: void
-    body:
-      syscall("PRINTLN",1)
-    end body
-  end function
-end module
diff --git a/src/main/java/org/jcnc/snow/compiler/semantic/analyzers/expression/CallExpressionAnalyzer.java b/src/main/java/org/jcnc/snow/compiler/semantic/analyzers/expression/CallExpressionAnalyzer.java
index 8c2eddc..df0993c 100644
--- a/src/main/java/org/jcnc/snow/compiler/semantic/analyzers/expression/CallExpressionAnalyzer.java
+++ b/src/main/java/org/jcnc/snow/compiler/semantic/analyzers/expression/CallExpressionAnalyzer.java
@@ -20,7 +20,7 @@ import java.util.List;
  * <p>
  * 它负责处理类似 {@code callee(arg1, arg2, ...)} 形式的调用表达式，执行如下操作:
  * <ul>
- *   <li>识别调用目标（支持模块成员函数调用和当前模块函数调用）；</li>
+ *   <li>识别调用目标（支持模块成员函数调用和当前模块函数调用，也支持自动在所有已导入模块中查找唯一同名函数）；</li>
  *   <li>根据被调用函数的参数签名检查实参数量和类型的兼容性；</li>
  *   <li>支持数值参数的宽化转换（如 int → double）；</li>
  *   <li>支持数值到字符串的隐式转换（自动视为调用 {@code to_string}）；</li>
@@ -77,8 +77,38 @@ public class CallExpressionAnalyzer implements ExpressionAnalyzer<CallExpression
             return BuiltinType.INT;
         }
 
-        // 查找目标函数签名
+        // 查找目标函数签名（先在当前模块/显式模块查找）
         FunctionType ft = target.getFunctions().get(functionName);
+
+        // 如果当前模块未找到，再自动遍历所有已导入模块寻找唯一同名函数
+        if (ft == null && target == mi) {
+            ModuleInfo foundModule = null;
+            FunctionType foundType = null;
+            for (String importName : mi.getImports()) {
+                ModuleInfo imported = ctx.getModules().get(importName);
+                if (imported == null) continue;
+                FunctionType candidate = imported.getFunctions().get(functionName);
+                if (candidate != null) {
+                    if (foundModule != null) {
+                        // 多个导入模块含有同名函数，二义性，报错
+                        ctx.getErrors().add(new SemanticError(callee,
+                                "函数调用不明确: " + functionName +
+                                        " 同时存在于模块 " + foundModule.getName() +
+                                        " 和 " + imported.getName()));
+                        ctx.log("错误: 函数调用不明确 " + functionName);
+                        return BuiltinType.INT;
+                    }
+                    foundModule = imported;
+                    foundType = candidate;
+                }
+            }
+            if (foundType != null) {
+                target = foundModule;
+                ft = foundType;
+            }
+        }
+
+        // 最终未找到则报错
         if (ft == null) {
             ctx.getErrors().add(new SemanticError(callee,
                     "函数未定义: " + functionName));

From b8c57b6c49605d5f32dd51eac3c5c2ee1a7c0a1b Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Sun, 20 Jul 2025 20:15:07 +0800
Subject: [PATCH 13/36] =?UTF-8?q?test:=20=E4=BF=AE=E6=94=B9=E7=A4=BA?=
 =?UTF-8?q?=E4=BE=8B=E4=BB=A3=E7=A0=81?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 playground/BugFarm/Bug1/Main.snow |  2 +-
 playground/Demo/Demo14/Main.snow  | 15 +++++++--------
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/playground/BugFarm/Bug1/Main.snow b/playground/BugFarm/Bug1/Main.snow
index 3c4df88..3468433 100644
--- a/playground/BugFarm/Bug1/Main.snow
+++ b/playground/BugFarm/Bug1/Main.snow
@@ -2,7 +2,7 @@ module: Main
     function: main
         return_type: void
         body:
-            declare abc:string ="0"
+            declare abc:int =1
         end body
     end function
 end module
diff --git a/playground/Demo/Demo14/Main.snow b/playground/Demo/Demo14/Main.snow
index baf23e4..42049ea 100644
--- a/playground/Demo/Demo14/Main.snow
+++ b/playground/Demo/Demo14/Main.snow
@@ -1,11 +1,10 @@
 module: Main
-  import: BuiltinUtils
+    import: BuiltinUtils
 
-  function: main
-    return_type: void
-    body:
-      BuiltinUtils.print(1)
-      BuiltinUtils.println(2)
-    end body
-  end function
+    function: main
+        return_type: void
+        body:
+            syscall("PRINT",1)
+        end body
+    end function
 end module
\ No newline at end of file

From 3aa38027c87334c0b2750e4cc9069d8fbab865da Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Sun, 20 Jul 2025 20:45:17 +0800
Subject: [PATCH 14/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=E5=AF=B9?=
 =?UTF-8?q?=E5=AD=97=E7=AC=A6=E4=B8=B2=E5=AD=97=E9=9D=A2=E9=87=8F=E7=9A=84?=
 =?UTF-8?q?=E6=94=AF=E6=8C=81?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 在 ExpressionBuilder 类中增加了处理字符串字面量的逻辑
- 新增 buildStringLiteral 方法用于生成字符串常量寄存器
- 更新了 build 方法的 switch 语句，支持 StringLiteralNode 类型
- 优化了代码结构，提高了可读性和可维护性
---
 .../ir/builder/ExpressionBuilder.java         | 28 +++++++++++++++++--
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/ir/builder/ExpressionBuilder.java b/src/main/java/org/jcnc/snow/compiler/ir/builder/ExpressionBuilder.java
index d56103a..31e2973 100644
--- a/src/main/java/org/jcnc/snow/compiler/ir/builder/ExpressionBuilder.java
+++ b/src/main/java/org/jcnc/snow/compiler/ir/builder/ExpressionBuilder.java
@@ -34,13 +34,14 @@ public record ExpressionBuilder(IRContext ctx) {
      * <p>会根据节点的实际类型分别处理: 
      * <ul>
      *   <li>数字字面量: 新建常量寄存器</li>
+     *   <li>字符串字面量: 新建常量寄存器（字符串类型）</li>
      *   <li>布尔字面量: 生成值为 0 或 1 的常量寄存器</li>
      *   <li>标识符: 查找当前作用域中的寄存器</li>
      *   <li>二元表达式: 递归处理子表达式并进行相应运算</li>
-     *   <li>一元运算符: 
+     *   <li>一元运算符:
      *     <ul>
      *        <li><code>-x</code>（取负，生成 <code>NEG_I32</code> 指令）与</li>
-     *        <li>code>!x</code>（逻辑非，转换为 <code>x == 0</code> 比较指令）</li>
+     *        <li><code>!x</code>（逻辑非，转换为 <code>x == 0</code> 比较指令）</li>
      *     </ul>
      *   </li>
      *   <li>函数调用: 生成对应的Call指令</li>
@@ -51,11 +52,12 @@ public record ExpressionBuilder(IRContext ctx) {
      * @return 该表达式的计算结果寄存器
      * @throws IllegalStateException 如果遇到未定义的标识符或不支持的表达式类型
      */
-
     public IRVirtualRegister build(ExpressionNode expr) {
         return switch (expr) {
             // 数字字面量
             case NumberLiteralNode n -> buildNumberLiteral(n.value());
+            // 字符串字面量
+            case StringLiteralNode s -> buildStringLiteral(s.value());
             // 布尔字面量
             case BoolLiteralNode b   -> buildBoolLiteral(b.getValue());
             // 标识符
@@ -69,6 +71,7 @@ public record ExpressionBuilder(IRContext ctx) {
             case BinaryExpressionNode bin -> buildBinary(bin);
             // 函数调用
             case CallExpressionNode call -> buildCall(call);
+            // 一元表达式
             case UnaryExpressionNode u  -> buildUnary(u);
             default -> throw new IllegalStateException(
                     "不支持的表达式类型: " + expr.getClass().getSimpleName());
@@ -111,6 +114,12 @@ public record ExpressionBuilder(IRContext ctx) {
             // 数字字面量，直接加载到目标寄存器
             case NumberLiteralNode n ->
                     InstructionFactory.loadConstInto(ctx, dest, ExpressionUtils.buildNumberConstant(ctx, n.value()));
+            // 字符串字面量，直接加载到目标寄存器
+            case StringLiteralNode s ->
+                    InstructionFactory.loadConstInto(ctx, dest, new IRConstant(s.value()));
+            // 布尔字面量，直接加载到目标寄存器
+            case BoolLiteralNode b ->
+                    InstructionFactory.loadConstInto(ctx, dest, new IRConstant(b.getValue() ? 1 : 0));
             // 标识符，查找并move到目标寄存器
             case IdentifierNode id -> {
                 IRVirtualRegister src = ctx.getScope().lookup(id.name());
@@ -223,6 +232,19 @@ public record ExpressionBuilder(IRContext ctx) {
         return reg;
     }
 
+    /**
+     * 处理字符串字面量，生成常量寄存器和加载指令。
+     *
+     * @param value 字符串内容
+     * @return 存放该字符串常量的寄存器
+     */
+    private IRVirtualRegister buildStringLiteral(String value) {
+        IRConstant constant = new IRConstant(value);
+        IRVirtualRegister reg = ctx.newRegister();
+        ctx.addInstruction(new LoadConstInstruction(reg, constant));
+        return reg;
+    }
+
     /** 布尔字面量 → CONST （true=1，false=0）*/
     private IRVirtualRegister buildBoolLiteral(boolean value) {
         IRConstant constant = new IRConstant(value ? 1 : 0);

From c6067a875806f722721c1dac79e4dd3a4276d8d2 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 16:46:34 +0800
Subject: [PATCH 15/36] =?UTF-8?q?feat:=20=E5=A2=9E=E5=8A=A0=E5=BC=95?=
 =?UTF-8?q?=E7=94=A8=E7=B1=BB=E5=9E=8B=E5=B8=B8=E9=87=8F=E6=94=AF=E6=8C=81?=
 =?UTF-8?q?=E5=B9=B6=E4=BC=98=E5=8C=96=E5=8F=8D=E7=A0=81=E6=98=A0=E5=B0=84?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 在 OPCODE_MAP 中添加 R_PUSH、R_LOAD 和 R_STORE 指令- 优化反码映射逻辑，支持十六进制表示的指令码
- 在 getConstType 方法中增加对 String 类型的支持
---
 .../snow/compiler/backend/utils/OpHelper.java    | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/backend/utils/OpHelper.java b/src/main/java/org/jcnc/snow/compiler/backend/utils/OpHelper.java
index d006802..977c85e 100644
--- a/src/main/java/org/jcnc/snow/compiler/backend/utils/OpHelper.java
+++ b/src/main/java/org/jcnc/snow/compiler/backend/utils/OpHelper.java
@@ -167,6 +167,9 @@ public final class OpHelper {
         map.put("D2I", Integer.toString(VMOpCode.D2I));
         map.put("D2L", Integer.toString(VMOpCode.D2L));
         map.put("D2F", Integer.toString(VMOpCode.D2F));
+        map.put("R_PUSH", Integer.toString(VMOpCode.R_PUSH));
+        map.put("R_LOAD", Integer.toString(VMOpCode.R_LOAD));
+        map.put("R_STORE", Integer.toString(VMOpCode.R_STORE));
         map.put("POP", Integer.toString(VMOpCode.POP));
         map.put("DUP", Integer.toString(VMOpCode.DUP));
         map.put("SWAP", Integer.toString(VMOpCode.SWAP));
@@ -180,7 +183,15 @@ public final class OpHelper {
         OPCODE_MAP = Collections.unmodifiableMap(map);
 
         Map<Integer, String> revmap = new HashMap<>();  // reverse map
-        OPCODE_MAP.forEach((key, value) -> revmap.put(Integer.parseInt(value), key));
+        OPCODE_MAP.forEach((key, value) -> {
+            int codeInt;
+            if (value.startsWith("0x") || value.startsWith("0X")) {
+                codeInt = Integer.parseInt(value.substring(2), 16);
+            } else {
+                codeInt = Integer.parseInt(value);
+            }
+            revmap.put(codeInt, key);
+        });
         OPCODE_NAME_MAP = Collections.unmodifiableMap(revmap);
     }
 
@@ -222,11 +233,13 @@ public final class OpHelper {
         if (v instanceof Byte) return "B";
         if (v instanceof Double) return "D";
         if (v instanceof Float) return "F";
+        if (v instanceof String) return "R";   //引用类型
         throw new IllegalStateException("Unknown const type: " + v.getClass());
     }
 
     /**
      * 根据 opcode 数值的字符串形式获取指令名
+     *
      * @param code 字符串形式的 opcode 数值
      * @return opcode 对应的指令名
      */
@@ -236,6 +249,7 @@ public final class OpHelper {
 
     /**
      * 根据 opcode 获取指令名
+     *
      * @param code opcode
      * @return opcode 对应的指令名
      */

From 2cb428ed9ba992150f0761a92787a6bb3be3a007 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 16:48:50 +0800
Subject: [PATCH 16/36] =?UTF-8?q?feat:=20=E6=96=B0=E5=A2=9E=E5=BC=95?=
 =?UTF-8?q?=E7=94=A8=E6=8E=A7=E5=88=B6=E5=91=BD=E4=BB=A4?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 添加 RPushCommand、RLoadCommand 和 RStoreCommand 三个引用控制命令类
- 在 CommandFactory 中注册这三个命令
---
 .../org/jcnc/snow/vm/factories/CommandFactory.java    | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java b/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
index dbdab0f..71479a3 100644
--- a/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
+++ b/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
@@ -6,6 +6,9 @@ import org.jcnc.snow.vm.commands.type.control.double64.*;
 import org.jcnc.snow.vm.commands.type.control.float32.*;
 import org.jcnc.snow.vm.commands.type.control.int32.*;
 import org.jcnc.snow.vm.commands.type.control.long64.*;
+import org.jcnc.snow.vm.commands.type.control.ref.RLoadCommand;
+import org.jcnc.snow.vm.commands.type.control.ref.RPushCommand;
+import org.jcnc.snow.vm.commands.type.control.ref.RStoreCommand;
 import org.jcnc.snow.vm.commands.type.control.short16.*;
 import org.jcnc.snow.vm.commands.type.control.byte8.BAndCommand;
 import org.jcnc.snow.vm.commands.type.control.byte8.BOrCommand;
@@ -62,6 +65,7 @@ public class CommandFactory {
 
     static {
 
+
         // region Type Control (0x0000-0x00BF)
         // region Byte8	 (0x0000-0x001F)
         COMMANDS[VMOpCode.B_ADD]   = new BAddCommand();
@@ -205,6 +209,7 @@ public class CommandFactory {
         COMMANDS[VMOpCode.D_CL]    = new DCLCommand();
         COMMANDS[VMOpCode.D_CLE]   = new DCLECommand();
         // endregion
+
         // endregion
 
         // region Type Conversion (0x00C0-0x00DF)
@@ -245,6 +250,12 @@ public class CommandFactory {
         COMMANDS[VMOpCode.D2F] = new D2FCommand();
         // endregion
 
+        // region Reference Control  (0x00E0-0x00EF)
+        COMMANDS[VMOpCode.R_PUSH] = new RPushCommand();
+        COMMANDS[VMOpCode.R_LOAD] = new RLoadCommand();
+        COMMANDS[VMOpCode.R_STORE] = new RStoreCommand();
+        // endregion
+
         // region Stack Control (0x0100-0x01FF)
         COMMANDS[VMOpCode.POP]  = new PopCommand();
         COMMANDS[VMOpCode.DUP]  = new DupCommand();

From fec9fe3527ac8111b82182980a775e0035b4e386 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 16:51:30 +0800
Subject: [PATCH 17/36] =?UTF-8?q?refactor:=20=E9=87=8D=E6=9E=84=20BuiltinT?=
 =?UTF-8?q?ypeRegistry=20=E7=B1=BB=E5=B9=B6=E4=BC=98=E5=8C=96=E6=96=87?=
 =?UTF-8?q?=E6=A1=A3=E6=B3=A8=E9=87=8A?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 重新整理基础类型表，添加 boolean 类型
- 优化文档注释，增加类和方法的详细描述
- 改进代码结构，提高可读性和可维护性
---
 .../semantic/core/BuiltinTypeRegistry.java    | 61 +++++++++++++------
 1 file changed, 41 insertions(+), 20 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java b/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
index e4bba8e..9f266c9 100644
--- a/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
+++ b/src/main/java/org/jcnc/snow/compiler/semantic/core/BuiltinTypeRegistry.java
@@ -7,42 +7,62 @@ import org.jcnc.snow.compiler.semantic.type.Type;
 import java.util.*;
 
 /**
- * 语言全部内置类型 / 模块 / 函数的注册中心。
+ * <b>BuiltinTypeRegistry - 语言全部内置类型/模块/函数注册中心</b>
  *
- * <p>目前同时注册：</p>
+ * <p>
+ * 该类统一注册编译器需要用到的所有基础类型、标准库模块与内核函数，供语义分析及类型检查阶段使用。
  * <ul>
- *   <li>所有基础类型（byte、short、int …）</li>
- *   <li>标准库模块 <b>BuiltinUtils</b> —— 仅声明函数签名，真正实现写在 Snow 源码中</li>
- *   <li>运行时内核函数 <b>syscall</b> —— 供标准库内部实现调用</li>
+ *   <li>所有基础类型（byte、short、int、long、float、double、string、boolean、void）</li>
+ *   <li>标准库模块 <b>BuiltinUtils</b>（仅注册函数签名，具体实现由 Snow 语言源码实现）</li>
+ *   <li>内核函数 <b>syscall</b>（供标准库内部实现调用）</li>
  * </ul>
+ * </p>
  */
 public final class BuiltinTypeRegistry {
 
-    /** 基础类型表：名称 → Type */
+    /**
+     * <b>基础类型表</b>：类型名称 → Type 实例
+     * <p>
+     * 本 Map 静态初始化，注册所有 Snow 语言基础类型，供类型检查与类型推断使用。
+     * </p>
+     */
     public static final Map<String, Type> BUILTIN_TYPES;
     static {
         Map<String, Type> t = new HashMap<>();
-        t.put("byte",   BuiltinType.BYTE);
-        t.put("short",  BuiltinType.SHORT);
-        t.put("int",    BuiltinType.INT);
-        t.put("long",   BuiltinType.LONG);
-        t.put("float",  BuiltinType.FLOAT);
-        t.put("double", BuiltinType.DOUBLE);
-        t.put("string", BuiltinType.STRING);
-        t.put("void",   BuiltinType.VOID);
-        BUILTIN_TYPES = Collections.unmodifiableMap(t);
+        t.put("byte",   BuiltinType.BYTE);     // 字节型
+        t.put("short",  BuiltinType.SHORT);    // 短整型
+        t.put("int",    BuiltinType.INT);      // 整型
+        t.put("long",   BuiltinType.LONG);     // 长整型
+        t.put("float",  BuiltinType.FLOAT);    // 单精度浮点
+        t.put("double", BuiltinType.DOUBLE);   // 双精度浮点
+        t.put("string", BuiltinType.STRING);   // 字符串
+        t.put("void",   BuiltinType.VOID);     // 无返回
+        t.put("boolean", BuiltinType.BOOLEAN); // 布尔类型
+
+        BUILTIN_TYPES = Collections.unmodifiableMap(t); // 不可变映射，防止被意外更改
     }
 
+    /**
+     * 私有构造方法，禁止实例化
+     */
     private BuiltinTypeRegistry() { }
 
     /**
-     * 供语义分析阶段调用：向上下文注入所有内置模块 / 函数声明。
+     * <b>初始化内置模块和函数声明</b>
+     *
+     * <p>
+     * 语义分析阶段调用，将所有基础模块与函数声明注册到语义上下文中。
+     * - 目前注册 BuiltinUtils 标准库模块（仅注册签名，不负责具体实现）。
+     * - syscall 函数注册到 BuiltinUtils 内，供标准库内部调用。
+     * </p>
+     *
+     * @param ctx 全局语义分析上下文，持有模块表
      */
     public static void init(Context ctx) {
-        /* ---------- BuiltinUtils ---------- */
-        ModuleInfo utils = new ModuleInfo("BuiltinUtils");
+        /* ---------- 注册标准库 os ---------- */
+        ModuleInfo utils = new ModuleInfo("os");
 
-        // syscall(string, int): void   —— 供 BuiltinUtils 内部使用
+        // syscall(string, int): void   —— 供标准库内部使用的调用接口
         utils.getFunctions().put(
                 "syscall",
                 new FunctionType(
@@ -51,6 +71,7 @@ public final class BuiltinTypeRegistry {
                 )
         );
 
-        ctx.getModules().putIfAbsent("BuiltinUtils", utils);
+        // 注册 BuiltinUtils 到上下文的模块表（若已存在则不重复添加）
+        ctx.getModules().putIfAbsent("os", utils);
     }
 }

From 7a52c7dd78f766114669d78e132a68d8acae06a9 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 16:56:18 +0800
Subject: [PATCH 18/36] =?UTF-8?q?feat:=20=E6=94=AF=E6=8C=81=20syscall=20?=
 =?UTF-8?q?=E8=B0=83=E7=94=A8=E7=9A=84=20VM=E6=8C=87=E4=BB=A4=E7=94=9F?=
 =?UTF-8?q?=E6=88=90?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 新增对 syscall 调用的特殊处理逻辑
- 支持 IRConstant 直接字面量和虚拟寄存器绑定的字符串常量作为 syscall 子命令
- 实现了 syscall 调用中参数压栈和 SYSCALL指令生成的逻辑
-优化了普通函数调用的指令生成流程
---
 .../backend/generator/CallGenerator.java      | 113 ++++++++++++++++--
 1 file changed, 101 insertions(+), 12 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/backend/generator/CallGenerator.java b/src/main/java/org/jcnc/snow/compiler/backend/generator/CallGenerator.java
index 84fe8cf..0f7c9c8 100644
--- a/src/main/java/org/jcnc/snow/compiler/backend/generator/CallGenerator.java
+++ b/src/main/java/org/jcnc/snow/compiler/backend/generator/CallGenerator.java
@@ -4,53 +4,142 @@ import org.jcnc.snow.compiler.backend.builder.VMProgramBuilder;
 import org.jcnc.snow.compiler.backend.core.InstructionGenerator;
 import org.jcnc.snow.compiler.backend.utils.OpHelper;
 import org.jcnc.snow.compiler.ir.common.GlobalFunctionTable;
+import org.jcnc.snow.compiler.ir.core.IRValue;
 import org.jcnc.snow.compiler.ir.instruction.CallInstruction;
+import org.jcnc.snow.compiler.ir.value.IRConstant;
 import org.jcnc.snow.compiler.ir.value.IRVirtualRegister;
+import org.jcnc.snow.vm.engine.VMOpCode;
 
-import java.util.Map;
+import java.util.*;
 
 /**
- * 将 IR CallInstruction 生成 VM 指令
+ * <b>CallGenerator - 将 IR {@code CallInstruction} 生成 VM 指令</b>
+ *
+ * <p>
+ * 本类负责将中间表示（IR）中的函数调用指令 {@link CallInstruction} 转换为虚拟机（VM）指令。
+ * 支持普通函数调用和特殊的 syscall 指令转换。
+ * </p>
+ *
+ * <p>
+ * <b>能力说明：</b>
+ * <ul>
+ *   <li>支持识别 {@code IRConstant} 直接字面量或已绑定到虚拟寄存器的字符串常量，直接降级为 {@code SYSCALL &lt;SUBCMD&gt;} 指令。</li>
+ *   <li>对普通函数，完成参数加载、调用、返回值保存等指令生成。</li>
+ * </ul>
+ * </p>
  */
 public class CallGenerator implements InstructionGenerator<CallInstruction> {
 
+    /**
+     * <虚拟寄存器 id, 对应的字符串常量>
+     * <p>用于记录虚拟寄存器与其绑定字符串常量的映射。由 {@link LoadConstGenerator} 在编译期间填充。</p>
+     */
+    private static final Map<Integer, String> STRING_CONST_POOL = new HashMap<>();
+
+    /**
+     * 注册字符串常量到虚拟寄存器
+     * <p>供 {@link LoadConstGenerator} 在加载字符串常量时调用。</p>
+     *
+     * @param regId 虚拟寄存器 id
+     * @param value 字符串常量值
+     */
+    public static void registerStringConst(int regId, String value) {
+        STRING_CONST_POOL.put(regId, value);
+    }
+
+    /**
+     * 返回本生成器支持的 IR 指令类型（CallInstruction）
+     */
     @Override
     public Class<CallInstruction> supportedClass() {
         return CallInstruction.class;
     }
 
+    /**
+     * 生成 VM 指令的主逻辑
+     *
+     * @param ins       当前 IR 指令（函数调用）
+     * @param out       指令输出构建器
+     * @param slotMap   IR 虚拟寄存器与物理槽位映射
+     * @param currentFn 当前函数名
+     */
     @Override
     public void generate(CallInstruction ins,
                          VMProgramBuilder out,
                          Map<IRVirtualRegister, Integer> slotMap,
                          String currentFn) {
 
-        /* 1. 推断返回值类型（用于非 void 情况下的 I/F/D/L_STORE） */
-        char retType = 'I';
+        /* ========== 特殊处理 syscall 调用 ========== */
+        if ("syscall".equals(ins.getFunctionName()) ||
+                ins.getFunctionName().endsWith(".syscall")) {
+
+            List<IRValue> args = ins.getArguments();
+            if (args.isEmpty()) {
+                throw new IllegalStateException("syscall 需要子命令参数");
+            }
+
+            // ---------- 0. 解析 syscall 子命令 ----------
+            // 子命令支持 IRConstant（直接字面量）或虚拟寄存器（需已绑定字符串）
+            String subcmd;
+            IRValue first = args.getFirst();
+
+            if (first instanceof IRConstant(Object value)) {    // 直接字面量
+                if (!(value instanceof String s))
+                    throw new IllegalStateException("syscall 第一个参数必须是字符串常量");
+                subcmd = s.toUpperCase(Locale.ROOT);
+
+            } else if (first instanceof IRVirtualRegister vr) {   // 虚拟寄存器
+                // 从常量池中查找是否已绑定字符串
+                subcmd = Optional.ofNullable(STRING_CONST_POOL.get(vr.id()))
+                        .orElseThrow(() ->
+                                new IllegalStateException("未找到 syscall 字符串常量绑定: " + vr));
+                subcmd = subcmd.toUpperCase(Locale.ROOT);
+
+            } else {
+                throw new IllegalStateException("syscall 第一个参数必须是字符串常量");
+            }
+
+            // ---------- 1. 压栈其余 syscall 参数（index 1 开始） ----------
+            for (int i = 1; i < args.size(); i++) {
+                IRVirtualRegister vr = (IRVirtualRegister) args.get(i);
+                int slotId = slotMap.get(vr);
+                char t = out.getSlotType(slotId);
+                if (t == '\0') t = 'I';  // 默认整型
+                out.emit(OpHelper.opcode(t + "_LOAD") + " " + slotId);
+            }
+
+            // ---------- 2. 生成 SYSCALL 指令 ----------
+            out.emit(VMOpCode.SYSCALL + " " + subcmd);
+            return;   // syscall 无返回值，直接返回
+        }
+
+        /* ========== 普通函数调用 ========== */
+
+        // ---------- 1. 推断返回值类型（非 void 返回时用） ----------
+        char retType = 'I';  // 默认为整型
         if (!ins.getArguments().isEmpty()) {
             int firstSlot = slotMap.get((IRVirtualRegister) ins.getArguments().getFirst());
             retType = out.getSlotType(firstSlot);
             if (retType == '\0') retType = 'I';
         }
 
-        /* 2. 依次加载实参 */
+        // ---------- 2. 加载全部实参 ----------
         for (var arg : ins.getArguments()) {
             int slotId = slotMap.get((IRVirtualRegister) arg);
             char t = out.getSlotType(slotId);
-            if (t == '\0') t = 'I';
+            if (t == '\0') t = 'I';  // 默认整型
             out.emit(OpHelper.opcode(t + "_LOAD") + " " + slotId);
         }
 
-        /* 3. 发出 CALL 指令 */
+        // ---------- 3. 发出 CALL 指令 ----------
         out.emitCall(ins.getFunctionName(), ins.getArguments().size());
 
-        /* 3.5 若被调用函数返回 void，则无需保存返回值 */
-        String rt = GlobalFunctionTable.getReturnType(ins.getFunctionName());
-        if ("void".equals(rt)) {
-            return;   // 直接结束，无 _STORE
+        // ---------- 3.5 如果为 void 返回直接结束 ----------
+        if ("void".equals(GlobalFunctionTable.getReturnType(ins.getFunctionName()))) {
+            return;
         }
 
-        /* 4. 保存返回值到目标槽 */
+        // ---------- 4. 保存返回值 ----------
         int destSlot = slotMap.get(ins.getDest());
         out.emit(OpHelper.opcode(retType + "_STORE") + " " + destSlot);
         out.setSlotType(destSlot, retType);

From 970976ecc5ad72e031b2167437056c5480182dc7 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 16:57:50 +0800
Subject: [PATCH 19/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=20VM=E9=80=80?=
 =?UTF-8?q?=E5=87=BA=E6=97=B6=E7=9A=84=E6=8F=90=E7=A4=BA=E4=BF=A1=E6=81=AF?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 在 VMLauncher 启动后增加提示信息 "=== Launching VM ==="
- 在 VM 退出后增加提示信息 "=== VM exited ==="
---
 src/main/java/org/jcnc/snow/pkg/tasks/CompileTask.java | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/main/java/org/jcnc/snow/pkg/tasks/CompileTask.java b/src/main/java/org/jcnc/snow/pkg/tasks/CompileTask.java
index f570bee..844c2fc 100644
--- a/src/main/java/org/jcnc/snow/pkg/tasks/CompileTask.java
+++ b/src/main/java/org/jcnc/snow/pkg/tasks/CompileTask.java
@@ -220,6 +220,7 @@ public final class CompileTask implements Task {
         if (runAfterCompile) {
             System.out.println("\n=== Launching VM ===");
             VMLauncher.main(new String[]{outputFile.toString()});
+            System.out.println("\n=== VM exited ===");
         }
 
         return 0;

From 3aef7cd9065fdaf4123a4ff0e9cbe3baca029491 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:06:40 +0800
Subject: [PATCH 20/36] =?UTF-8?q?refactor:=20=E9=87=8D=E6=9E=84=20Expressi?=
 =?UTF-8?q?onBuilder=20=E7=B1=BB?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 优化了代码结构，提高了代码的可读性和可维护性
- 添加了详细的注释，解释了各个方法的功能和实现细节
- 改进了对不同表达式类型的处理逻辑，增强了表达式构建的能力
- 优化了寄存器的使用和管理，提高了 IR 指令生成的效率
---
 .../ir/builder/ExpressionBuilder.java         | 319 ++++++++++--------
 1 file changed, 171 insertions(+), 148 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/ir/builder/ExpressionBuilder.java b/src/main/java/org/jcnc/snow/compiler/ir/builder/ExpressionBuilder.java
index 31e2973..58eccfc 100644
--- a/src/main/java/org/jcnc/snow/compiler/ir/builder/ExpressionBuilder.java
+++ b/src/main/java/org/jcnc/snow/compiler/ir/builder/ExpressionBuilder.java
@@ -5,130 +5,117 @@ import org.jcnc.snow.compiler.ir.instruction.CallInstruction;
 import org.jcnc.snow.compiler.ir.instruction.LoadConstInstruction;
 import org.jcnc.snow.compiler.ir.instruction.UnaryOperationInstruction;
 import org.jcnc.snow.compiler.ir.utils.ComparisonUtils;
+import org.jcnc.snow.compiler.ir.utils.ExpressionUtils;
 import org.jcnc.snow.compiler.ir.value.IRConstant;
 import org.jcnc.snow.compiler.ir.value.IRVirtualRegister;
-import org.jcnc.snow.compiler.ir.utils.ExpressionUtils;
 import org.jcnc.snow.compiler.parser.ast.*;
 import org.jcnc.snow.compiler.parser.ast.base.ExpressionNode;
 
 import java.util.*;
 
 /**
- * <b>表达式构建器</b>
+ * <b>ExpressionBuilder - 表达式 → IR 构建器</b>
+ *
  * <p>
- * 该类负责将抽象语法树（AST）的表达式节点转换为中间表示（IR）指令和虚拟寄存器，
- * 是编译器IR生成阶段的核心工具。
- * <br/>
- * 主要职责包括: 
+ * 负责将 AST 表达式节点递归转换为 IR 虚拟寄存器操作，并生成对应的 IR 指令序列。
+ * 支持字面量、标识符、二元表达式、一元表达式、函数调用等多种类型表达式。
+ * </p>
+ *
+ * <p>
+ * 主要功能：
  * <ul>
- *   <li>将数字字面量、标识符、二元表达式、函数调用等AST表达式节点，翻译为对应的IR指令序列</li>
- *   <li>管理并分配虚拟寄存器，保证IR操作的数据流正确</li>
+ *     <li>将表达式节点映射为虚拟寄存器</li>
+ *     <li>为每种表达式类型生成对应 IR 指令</li>
+ *     <li>支持表达式嵌套的递归构建</li>
+ *     <li>支持写入指定目标寄存器，避免冗余的 move 指令</li>
  * </ul>
- * <p>
+ * </p>
  */
 public record ExpressionBuilder(IRContext ctx) {
 
+    /* ───────────────── 顶层入口 ───────────────── */
+
     /**
-     * 构建并返回某个表达式节点对应的虚拟寄存器。
+     * 构建任意 AST 表达式节点，自动为其分配一个新的虚拟寄存器，并返回该寄存器。
      *
-     * <p>会根据节点的实际类型分别处理: 
-     * <ul>
-     *   <li>数字字面量: 新建常量寄存器</li>
-     *   <li>字符串字面量: 新建常量寄存器（字符串类型）</li>
-     *   <li>布尔字面量: 生成值为 0 或 1 的常量寄存器</li>
-     *   <li>标识符: 查找当前作用域中的寄存器</li>
-     *   <li>二元表达式: 递归处理子表达式并进行相应运算</li>
-     *   <li>一元运算符:
-     *     <ul>
-     *        <li><code>-x</code>（取负，生成 <code>NEG_I32</code> 指令）与</li>
-     *        <li><code>!x</code>（逻辑非，转换为 <code>x == 0</code> 比较指令）</li>
-     *     </ul>
-     *   </li>
-     *   <li>函数调用: 生成对应的Call指令</li>
-     *   <li>其它类型不支持，抛出异常</li>
-     * </ul>
+     * <p>
+     * 这是表达式 IR 生成的核心入口。它会根据不同的表达式类型进行分派，递归构建 IR 指令。
+     * </p>
      *
-     * @param expr 要转换的表达式AST节点
-     * @return 该表达式的计算结果寄存器
-     * @throws IllegalStateException 如果遇到未定义的标识符或不支持的表达式类型
+     * @param expr 任意 AST 表达式节点
+     * @return 存储该表达式结果的虚拟寄存器
+     * @throws IllegalStateException 遇到不支持的表达式类型或未定义标识符
      */
     public IRVirtualRegister build(ExpressionNode expr) {
         return switch (expr) {
-            // 数字字面量
+            // 数字字面量，例如 123、3.14
             case NumberLiteralNode n -> buildNumberLiteral(n.value());
-            // 字符串字面量
+            // 字符串字面量，例如 "abc"
             case StringLiteralNode s -> buildStringLiteral(s.value());
-            // 布尔字面量
+            // 布尔字面量，例如 true / false
             case BoolLiteralNode b   -> buildBoolLiteral(b.getValue());
-            // 标识符
+            // 标识符（变量名），如 a、b
             case IdentifierNode id -> {
+                // 查找当前作用域中的变量寄存器
                 IRVirtualRegister reg = ctx.getScope().lookup(id.name());
                 if (reg == null)
                     throw new IllegalStateException("未定义标识符: " + id.name());
                 yield reg;
             }
-            // 二元表达式
+            // 二元表达式（如 a+b, x==y）
             case BinaryExpressionNode bin -> buildBinary(bin);
-            // 函数调用
-            case CallExpressionNode call -> buildCall(call);
-            // 一元表达式
-            case UnaryExpressionNode u  -> buildUnary(u);
+            // 函数/方法调用表达式
+            case CallExpressionNode   call -> buildCall(call);
+            // 一元表达式（如 -a, !a）
+            case UnaryExpressionNode  un   -> buildUnary(un);
+
+            // 默认分支：遇到未知表达式类型则直接抛异常
             default -> throw new IllegalStateException(
                     "不支持的表达式类型: " + expr.getClass().getSimpleName());
         };
     }
 
-    /** 处理一元表达式 */
-    private IRVirtualRegister buildUnary(UnaryExpressionNode un) {
-        String            op  = un.operator();
-        IRVirtualRegister val = build(un.operand());
-
-        //  -x  → NEG_*（根据类型自动选择位宽）
-        if (op.equals("-")) {
-            IRVirtualRegister dest = ctx.newRegister();
-            IROpCode          code = ExpressionUtils.negOp(un.operand());
-            ctx.addInstruction(new UnaryOperationInstruction(code, dest, val));
-            return dest;
-        }
-
-        //  !x  →  (x == 0)
-        if (op.equals("!")) {
-            IRVirtualRegister zero = InstructionFactory.loadConst(ctx, 0);
-            return InstructionFactory.binOp(ctx, IROpCode.CMP_IEQ, val, zero);
-        }
-
-        throw new IllegalStateException("未知一元运算符: " + op);
-    }
+    /* ───────────────── 写入指定寄存器 ───────────────── */
 
     /**
-     * 直接将表达式计算结果写入指定的目标寄存器（dest）。
-     * <p>
-     * 与{@link #build(ExpressionNode)}类似，但支持目标寄存器复用（避免不必要的move）。
+     * 生成表达式，并将其结果直接写入目标寄存器，避免冗余的 move 操作。
      *
-     * @param node 表达式AST节点
-     * @param dest 目标寄存器
-     * @throws IllegalStateException 未定义标识符/不支持的表达式类型时报错
+     * <p>
+     * 某些简单表达式（如字面量、变量名）可以直接写入目标寄存器；复杂表达式则会先 build 到新寄存器，再 move 到目标寄存器。
+     * </p>
+     *
+     * @param node 要生成的表达式节点
+     * @param dest 目标虚拟寄存器（用于存储结果）
      */
     public void buildInto(ExpressionNode node, IRVirtualRegister dest) {
         switch (node) {
-            // 数字字面量，直接加载到目标寄存器
+            // 数字字面量：生成 loadConst 指令写入目标寄存器
             case NumberLiteralNode n ->
-                    InstructionFactory.loadConstInto(ctx, dest, ExpressionUtils.buildNumberConstant(ctx, n.value()));
-            // 字符串字面量，直接加载到目标寄存器
+                    InstructionFactory.loadConstInto(
+                            ctx, dest, ExpressionUtils.buildNumberConstant(ctx, n.value()));
+
+            // 字符串字面量：生成 loadConst 指令写入目标寄存器
             case StringLiteralNode s ->
-                    InstructionFactory.loadConstInto(ctx, dest, new IRConstant(s.value()));
-            // 布尔字面量，直接加载到目标寄存器
+                    InstructionFactory.loadConstInto(
+                            ctx, dest, new IRConstant(s.value()));
+
+            // 布尔字面量：转换为 int 1/0，生成 loadConst
             case BoolLiteralNode b ->
-                    InstructionFactory.loadConstInto(ctx, dest, new IRConstant(b.getValue() ? 1 : 0));
-            // 标识符，查找并move到目标寄存器
+                    InstructionFactory.loadConstInto(
+                            ctx, dest, new IRConstant(b.getValue() ? 1 : 0));
+
+            // 标识符：查表获取原寄存器，然后 move 到目标寄存器
             case IdentifierNode id -> {
                 IRVirtualRegister src = ctx.getScope().lookup(id.name());
-                if (src == null) throw new IllegalStateException("未定义标识符: " + id.name());
+                if (src == null)
+                    throw new IllegalStateException("未定义标识符: " + id.name());
                 InstructionFactory.move(ctx, src, dest);
             }
-            // 二元表达式，直接写入目标寄存器
+
+            // 二元表达式：递归生成并写入目标寄存器
             case BinaryExpressionNode bin -> buildBinaryInto(bin, dest);
-            // 其他表达式，先递归生成寄存器，再move到目标寄存器
+
+            // 其它复杂情况：先 build 到新寄存器，再 move 到目标寄存器
             default -> {
                 IRVirtualRegister tmp = build(node);
                 InstructionFactory.move(ctx, tmp, dest);
@@ -136,41 +123,100 @@ public record ExpressionBuilder(IRContext ctx) {
         }
     }
 
+    /* ───────────────── 具体表达式类型 ───────────────── */
+
     /**
-     * 构建二元表达式的IR，生成新寄存器存储结果。
-     * <p>
-     * 先递归构建左右操作数，之后根据操作符类别（算术或比较）决定生成的IR操作码，
-     * 并生成对应的二元运算指令。
+     * 一元表达式构建
      *
-     * @param bin 二元表达式节点
-     * @return 存放结果的虚拟寄存器
+     * <p>
+     * 支持算术取负（-a）、逻辑非（!a）等一元运算符。
+     * </p>
+     *
+     * @param un 一元表达式节点
+     * @return 结果存储的新分配虚拟寄存器
      */
-    private IRVirtualRegister buildBinary(BinaryExpressionNode bin) {
-        String op = bin.operator();
-        IRVirtualRegister left  = build(bin.left());
-        IRVirtualRegister right = build(bin.right());
+    private IRVirtualRegister buildUnary(UnaryExpressionNode un) {
+        // 递归生成操作数的寄存器
+        IRVirtualRegister src  = build(un.operand());
+        // 分配目标寄存器
+        IRVirtualRegister dest = ctx.newRegister();
 
-        // 1. 比较运算
-        if (ComparisonUtils.isComparisonOperator(op)) {
-            return InstructionFactory.binOp(
-                    ctx,
-                    ComparisonUtils.cmpOp(ctx.getScope().getVarTypes(), op, bin.left(), bin.right()),
-                    left, right);
+        switch (un.operator()) {
+            // 算术负号：生成取负指令
+            case "-" -> ctx.addInstruction(
+                    new UnaryOperationInstruction(ExpressionUtils.negOp(un.operand()), dest, src));
+            // 逻辑非：等价于 a == 0，生成比较指令
+            case "!" -> {
+                IRVirtualRegister zero = InstructionFactory.loadConst(ctx, 0);
+                return InstructionFactory.binOp(ctx, IROpCode.CMP_IEQ, src, zero);
+            }
+            // 其它一元运算符不支持，抛异常
+            default -> throw new IllegalStateException("未知一元运算符: " + un.operator());
         }
-
-        // 2. 其他算术 / 逻辑运算
-        IROpCode code = ExpressionUtils.resolveOpCode(op, bin.left(), bin.right());
-        if (code == null) throw new IllegalStateException("不支持的运算符: " + op);
-        return InstructionFactory.binOp(ctx, code, left, right);
+        return dest;
     }
 
     /**
-     * 将二元表达式的结果直接写入指定寄存器dest。
-     * <p>
-     * 结构与{@link #buildBinary(BinaryExpressionNode)}类似，但不会新分配寄存器。
+     * 构建函数或方法调用表达式。
+     *
+     * @param call AST 调用表达式节点
+     * @return 存储调用结果的虚拟寄存器
+     */
+    private IRVirtualRegister buildCall(CallExpressionNode call) {
+        // 递归生成所有参数（实参）对应的寄存器
+        List<IRVirtualRegister> argv = call.arguments().stream().map(this::build).toList();
+
+        // 解析被调用目标名，支持普通函数/成员方法
+        String callee = switch (call.callee()) {
+            // 成员方法调用，例如 obj.foo()
+            case MemberExpressionNode m when m.object() instanceof IdentifierNode id
+                    -> id.name() + "." + m.member();
+            // 普通函数调用
+            case IdentifierNode id -> id.name();
+            // 其它情况暂不支持
+            default -> throw new IllegalStateException("不支持的调用目标: " + call.callee().getClass().getSimpleName());
+        };
+
+        // 为返回值分配新寄存器，生成 Call 指令
+        IRVirtualRegister dest = ctx.newRegister();
+        ctx.addInstruction(new CallInstruction(dest, callee, new ArrayList<>(argv)));
+        return dest;
+    }
+
+    /**
+     * 二元表达式构建，结果存储到新寄存器。
+     * <br>
+     * 支持算术、位运算与比较（==, !=, >, <, ...）。
      *
      * @param bin 二元表达式节点
-     * @param dest 目标寄存器
+     * @return 存储表达式结果的虚拟寄存器
+     */
+    private IRVirtualRegister buildBinary(BinaryExpressionNode bin) {
+        // 递归生成左、右子表达式的寄存器
+        IRVirtualRegister a = build(bin.left());
+        IRVirtualRegister b = build(bin.right());
+        String op = bin.operator();
+
+        // 比较运算符（==、!=、>、< 等），需要生成条件跳转或布尔值寄存器
+        if (ComparisonUtils.isComparisonOperator(op)) {
+            return InstructionFactory.binOp(
+                    ctx,
+                    // 通过比较工具获得合适的 IR 操作码
+                    ComparisonUtils.cmpOp(ctx.getScope().getVarTypes(), op, bin.left(), bin.right()),
+                    a, b);
+        }
+
+        // 其它算术/位运算
+        IROpCode code = ExpressionUtils.resolveOpCode(op, bin.left(), bin.right());
+        if (code == null) throw new IllegalStateException("不支持的运算符: " + op);
+        return InstructionFactory.binOp(ctx, code, a, b);
+    }
+
+    /**
+     * 二元表达式构建，结果直接写入目标寄存器（用于赋值左值等优化场景）。
+     *
+     * @param bin 二元表达式节点
+     * @param dest 目标虚拟寄存器
      */
     private void buildBinaryInto(BinaryExpressionNode bin, IRVirtualRegister dest) {
         IRVirtualRegister a = build(bin.left());
@@ -189,67 +235,44 @@ public record ExpressionBuilder(IRContext ctx) {
         }
     }
 
-    /**
-     * 处理函数调用表达式，生成对应的Call指令和目标寄存器。
-     * <p>
-     * 支持普通标识符调用和成员调用（如 mod.func），会为每个参数依次生成子表达式的寄存器。
-     *
-     * @param call 调用表达式AST节点
-     * @return 返回结果存放的寄存器
-     */
-    private IRVirtualRegister buildCall(CallExpressionNode call) {
-        // 递归构建所有参数的寄存器
-        List<IRVirtualRegister> argv = call.arguments().stream()
-                .map(this::build)
-                .toList();
-        // 获取完整调用目标名称（支持成员/模块调用和普通调用）
-        String fullName = switch (call.callee()) {
-            case MemberExpressionNode member when member.object() instanceof IdentifierNode _ ->
-                    ((IdentifierNode)member.object()).name() + "." + member.member();
-            case IdentifierNode id -> id.name();
-            default -> throw new IllegalStateException("不支持的调用目标: " + call.callee().getClass().getSimpleName());
-        };
-        // 申请目标寄存器
-        IRVirtualRegister dest = ctx.newRegister();
-        // 添加Call指令到IR上下文
-        ctx.addInstruction(new CallInstruction(dest, fullName, new ArrayList<>(argv)));
-        return dest;
-    }
+    /* ───────────────── 字面量辅助方法 ───────────────── */
 
     /**
-     * 处理数字字面量，生成常量寄存器和加载指令。
-     * <p>
-     * 会将字符串型字面量（如 "123", "1.0f"）解析为具体的IRConstant，
-     * 并分配一个新的虚拟寄存器来存放该常量。
+     * 构建数字字面量表达式（如 123），分配新寄存器并生成 LoadConst 指令。
      *
-     * @param value 字面量字符串
-     * @return 存放该常量的寄存器
+     * @param value 字面量文本（字符串格式）
+     * @return 存储该字面量的寄存器
      */
     private IRVirtualRegister buildNumberLiteral(String value) {
-        IRConstant constant = ExpressionUtils.buildNumberConstant(ctx, value);
-        IRVirtualRegister reg = ctx.newRegister();
-        ctx.addInstruction(new LoadConstInstruction(reg, constant));
-        return reg;
+        IRConstant c = ExpressionUtils.buildNumberConstant(ctx, value);
+        IRVirtualRegister r = ctx.newRegister();
+        ctx.addInstruction(new LoadConstInstruction(r, c));
+        return r;
     }
 
     /**
-     * 处理字符串字面量，生成常量寄存器和加载指令。
+     * 构建字符串字面量表达式，分配新寄存器并生成 LoadConst 指令。
      *
      * @param value 字符串内容
-     * @return 存放该字符串常量的寄存器
+     * @return 存储该字符串的寄存器
      */
     private IRVirtualRegister buildStringLiteral(String value) {
-        IRConstant constant = new IRConstant(value);
-        IRVirtualRegister reg = ctx.newRegister();
-        ctx.addInstruction(new LoadConstInstruction(reg, constant));
-        return reg;
+        IRConstant c = new IRConstant(value);
+        IRVirtualRegister r = ctx.newRegister();
+        ctx.addInstruction(new LoadConstInstruction(r, c));
+        return r;
     }
 
-    /** 布尔字面量 → CONST （true=1，false=0）*/
-    private IRVirtualRegister buildBoolLiteral(boolean value) {
-        IRConstant constant = new IRConstant(value ? 1 : 0);
-        IRVirtualRegister reg = ctx.newRegister();
-        ctx.addInstruction(new LoadConstInstruction(reg, constant));
-        return reg;
+    /**
+     * 构建布尔字面量表达式（true/false），分配新寄存器并生成 LoadConst 指令（1 表示 true，0 表示 false）。
+     *
+     * @param v 布尔值
+     * @return 存储 1/0 的寄存器
+     */
+    private IRVirtualRegister buildBoolLiteral(boolean v) {
+        IRConstant c = new IRConstant(v ? 1 : 0);
+        IRVirtualRegister r = ctx.newRegister();
+        ctx.addInstruction(new LoadConstInstruction(r, c));
+        return r;
     }
 }

From 6a339149f11f6584959cb7535b868a65c2eff744 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:09:26 +0800
Subject: [PATCH 21/36] =?UTF-8?q?feat:=20=E5=A2=9E=E5=BC=BA=20LoadConstGen?=
 =?UTF-8?q?erator=20=E5=8A=9F=E8=83=BD=E5=B9=B6=E4=BC=98=E5=8C=96=E4=BB=A3?=
 =?UTF-8?q?=E7=A0=81=E7=BB=93=E6=9E=84?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 优化类注释，明确类的功能和额外支持的特性
- 重构 generate 方法，提高代码可读性和维护性- 增加对字符串常量的处理，支持 syscall 降级场景
- 完善类型前缀处理，增加 'R' 前缀用于字符串常量
---
 .../backend/generator/LoadConstGenerator.java | 70 ++++++++++---------
 1 file changed, 36 insertions(+), 34 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/backend/generator/LoadConstGenerator.java b/src/main/java/org/jcnc/snow/compiler/backend/generator/LoadConstGenerator.java
index 760422a..a24f6d9 100644
--- a/src/main/java/org/jcnc/snow/compiler/backend/generator/LoadConstGenerator.java
+++ b/src/main/java/org/jcnc/snow/compiler/backend/generator/LoadConstGenerator.java
@@ -10,16 +10,18 @@ import org.jcnc.snow.compiler.ir.value.IRVirtualRegister;
 import java.util.Map;
 
 /**
- * 常量加载指令生成器
- * 该类用于生成将常量加载到虚拟机寄存器的指令，包括 PUSH 常量值和 STORE 到指定槽位，
- * 并为每个槽位设置正确的类型前缀（如 'I', 'L', 'F' 等）。
+ * <b>LoadConstGenerator - 将 IR {@code LoadConstInstruction} 生成 VM 指令</b>
+ *
+ * <p>
+ * 本类负责将 IR 层的常量加载指令 {@link LoadConstInstruction} 转换为对应的虚拟机指令。
+ * 额外支持：如果常量类型为 {@code String}，会同步登记到
+ * {@link CallGenerator} 的字符串常量池，方便 syscall 降级场景使用。
+ * </p>
  */
 public class LoadConstGenerator implements InstructionGenerator<LoadConstInstruction> {
 
     /**
-     * 返回本生成器支持的指令类型，即 LoadConstInstruction。
-     *
-     * @return 支持的指令类型的 Class 对象
+     * 指定本生成器支持的 IR 指令类型（LoadConstInstruction）
      */
     @Override
     public Class<LoadConstInstruction> supportedClass() {
@@ -27,49 +29,49 @@ public class LoadConstGenerator implements InstructionGenerator<LoadConstInstruc
     }
 
     /**
-     * 生成一条常量加载指令的目标虚拟机代码。
+     * 生成 VM 指令主流程
      *
-     * @param ins       当前要生成的 LoadConstInstruction 指令
-     * @param out       VMProgramBuilder，用于输出生成的虚拟机指令
-     * @param slotMap   IR 虚拟寄存器到实际槽位编号的映射表
-     * @param currentFn 当前函数名（如有需要可使用）
+     * @param ins       当前常量加载指令
+     * @param out       指令输出构建器
+     * @param slotMap   虚拟寄存器与物理槽位映射
+     * @param currentFn 当前函数名
      */
     @Override
     public void generate(LoadConstInstruction ins,
                          VMProgramBuilder out,
                          Map<IRVirtualRegister, Integer> slotMap,
                          String currentFn) {
-        // 1. 获取常量值（第一个操作数必为常量）
+
+        /* 1. 获取常量值 */
         IRConstant constant = (IRConstant) ins.operands().getFirst();
         Object value = constant.value();
 
-        // 2. 生成 PUSH 指令，将常量值推入操作数栈
-        // 通过 OpHelper 辅助方法获取合适的数据类型前缀
-        String pushOp = OpHelper.pushOpcodeFor(value);
-        out.emit(pushOp + " " + value);
+        /* 2. 生成 PUSH 指令，将常量值入栈 */
+        out.emit(OpHelper.pushOpcodeFor(value) + " " + value);
 
-        // 3. 生成 STORE 指令，将栈顶的值存入对应槽位（寄存器）
-        // 同样通过 OpHelper 获取对应类型的 STORE 指令
-        String storeOp = OpHelper.storeOpcodeFor(value);
-        // 获取目标虚拟寄存器对应的槽位编号
+        /* 3. STORE 到目标槽位 */
         int slot = slotMap.get(ins.dest());
-        out.emit(storeOp + " " + slot);
+        out.emit(OpHelper.storeOpcodeFor(value) + " " + slot);
 
-        // 4. 根据常量的 Java 类型，为槽位设置正确的前缀字符
-        // 这样在后续类型检查/运行时可用，常见前缀如 'I', 'L', 'F', 'D', 'S', 'B'
+        /* 4. 标记槽位数据类型（用于后续类型推断和 LOAD/STORE 指令选择） */
         char prefix = switch (value) {
-            case Integer _ -> 'I';  // 整型
-            case Long _ -> 'L';  // 长整型
-            case Short _ -> 'S';  // 短整型
-            case Byte _ -> 'B';  // 字节型
-            case Double _ -> 'D';  // 双精度浮点型
-            case Float _ -> 'F';  // 单精度浮点型
-            case Boolean _  -> 'I';  // 布尔（作为 0/1 整型存储）
-            case null, default ->
-                    throw new IllegalStateException("Unknown const type: " + (value != null ? value.getClass() : null));
+            case Integer _ -> 'I';   // 整型
+            case Long    _ -> 'L';   // 长整型
+            case Short   _ -> 'S';   // 短整型
+            case Byte    _ -> 'B';   // 字节型
+            case Double  _ -> 'D';   // 双精度
+            case Float   _ -> 'F';   // 单精度
+            case Boolean _ -> 'I';   // 布尔类型用 I 处理
+            case String  _ -> 'R';   // 字符串常量
+            case null, default ->    // 其它类型异常
+                    throw new IllegalStateException("未知的常量类型: "
+                            + (value != null ? value.getClass() : null));
         };
-
-        // 写入槽位类型映射表
         out.setSlotType(slot, prefix);
+
+        /* 5. 如果是字符串常量，则登记到 CallGenerator 的常量池，便于 syscall 字符串降级使用 */
+        if (value instanceof String s) {
+            CallGenerator.registerStringConst(ins.dest().id(), s);
+        }
     }
 }

From 8eeed6f6b999c059c2159eb589ae9b17491e0f2f Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:10:20 +0800
Subject: [PATCH 22/36] =?UTF-8?q?refactor:=20=E8=B0=83=E6=95=B4=E6=93=8D?=
 =?UTF-8?q?=E4=BD=9C=E6=95=B0=E6=A0=88=E6=89=93=E5=8D=B0=E6=A0=BC=E5=BC=8F?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 在操作数栈状态打印时，增加空行以提高可读性
---
 src/main/java/org/jcnc/snow/vm/module/OperandStack.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/java/org/jcnc/snow/vm/module/OperandStack.java b/src/main/java/org/jcnc/snow/vm/module/OperandStack.java
index 347387f..1e0d158 100644
--- a/src/main/java/org/jcnc/snow/vm/module/OperandStack.java
+++ b/src/main/java/org/jcnc/snow/vm/module/OperandStack.java
@@ -84,7 +84,7 @@ public class OperandStack {
      * </p>
      */
     public void printOperandStack() {
-        LoggingUtils.logInfo("Operand Stack state:", stack + "\n");
+        LoggingUtils.logInfo("\n\nOperand Stack state:", stack + "\n");
     }
 
     /**

From b4c933e3d4c310969a6ac265531e23d6b9d4c6fd Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:10:42 +0800
Subject: [PATCH 23/36] =?UTF-8?q?test:=20=E6=9B=B4=E6=96=B0=20Demo14=20?=
 =?UTF-8?q?=E7=A4=BA=E4=BE=8B=E7=A8=8B=E5=BA=8F?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 修改导入模块，使用 os 模块替代 BuiltinUtils
- 更新 syscall 调用，增加表达式计算
---
 playground/Demo/Demo14/Main.snow | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/playground/Demo/Demo14/Main.snow b/playground/Demo/Demo14/Main.snow
index 42049ea..8e5baff 100644
--- a/playground/Demo/Demo14/Main.snow
+++ b/playground/Demo/Demo14/Main.snow
@@ -1,10 +1,10 @@
 module: Main
-    import: BuiltinUtils
+    import: os
 
     function: main
         return_type: void
         body:
-            syscall("PRINT",1)
+            syscall("PRINT",2222+1)
         end body
     end function
 end module
\ No newline at end of file

From e7c7451004d8b5d99ee68212771332bf02bfe385 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:16:54 +0800
Subject: [PATCH 24/36] =?UTF-8?q?refactor:=20=E9=87=8D=E6=9E=84=20CallComm?=
 =?UTF-8?q?and=20=E7=B1=BB=E5=B9=B6=E4=BC=98=E5=8C=96=E6=96=87=E6=A1=A3?=
 =?UTF-8?q?=E6=B3=A8=E9=87=8A=20-=20=E9=87=8D=E6=96=B0=E7=BB=84=E7=BB=87?=
 =?UTF-8?q?=E7=B1=BB=E6=96=87=E6=A1=A3=EF=BC=8C=E5=A2=9E=E5=8A=A0=E5=AF=B9?=
 =?UTF-8?q?=20CallCommand=20=E5=8A=9F=E8=83=BD=E5=92=8C=E8=A1=8C=E4=B8=BA?=
 =?UTF-8?q?=E7=9A=84=E8=AF=A6=E7=BB=86=E6=8F=8F=E8=BF=B0=20-=20=E6=B7=BB?=
 =?UTF-8?q?=E5=8A=A0=20execute=20=E6=96=B9=E6=B3=95=E7=9A=84=E8=AF=A6?=
 =?UTF-8?q?=E7=BB=86=E6=B3=A8=E9=87=8A=EF=BC=8C=E6=98=8E=E7=A1=AE=E5=8F=82?=
 =?UTF-8?q?=E6=95=B0=E5=92=8C=E8=BF=94=E5=9B=9E=E5=80=BC=E7=9A=84=E7=94=A8?=
 =?UTF-8?q?=E9=80=94=20-=20=E4=BC=98=E5=8C=96=E4=BB=A3=E7=A0=81=E7=BB=93?=
 =?UTF-8?q?=E6=9E=84=EF=BC=8C=E6=8F=90=E9=AB=98=E5=8F=AF=E8=AF=BB=E6=80=A7?=
 =?UTF-8?q?=E5=92=8C=E5=8F=AF=E7=BB=B4=E6=8A=A4=E6=80=A7?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../vm/commands/flow/control/CallCommand.java | 42 +++++++++++++++++--
 1 file changed, 39 insertions(+), 3 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/vm/commands/flow/control/CallCommand.java b/src/main/java/org/jcnc/snow/vm/commands/flow/control/CallCommand.java
index befbfea..1171885 100644
--- a/src/main/java/org/jcnc/snow/vm/commands/flow/control/CallCommand.java
+++ b/src/main/java/org/jcnc/snow/vm/commands/flow/control/CallCommand.java
@@ -5,12 +5,48 @@ import org.jcnc.snow.vm.interfaces.Command;
 import org.jcnc.snow.vm.module.*;
 
 /**
- * CALL addr nArgs — pushes a new stack-frame, transfers the specified
- * argument count from the operand stack into the callee’s local slots
- * 0‥n-1 (left-to-right), then jumps to {@code addr}.
+ * The CallCommand class implements the {@link Command} interface and represents a subroutine/function call
+ * instruction in the virtual machine.
+ * <p>
+ * This command facilitates method invocation by creating a new stack frame, transferring arguments
+ * from the operand stack to the callee's local variable store, and jumping to the specified target address.
+ * </p>
+ *
+ * <p>Specific behavior:</p>
+ * <ul>
+ *     <li>Parses the target address and the number of arguments from the instruction parameters.</li>
+ *     <li>Validates the operands and checks for correct argument count.</li>
+ *     <li>Builds a new local variable store for the callee and transfers arguments from the operand stack
+ *         (left-to-right order, where the top of the stack is the last argument).</li>
+ *     <li>Pushes a new stack frame onto the call stack, saving the return address and local variables.</li>
+ *     <li>Jumps to the specified target address to begin execution of the callee function.</li>
+ *     <li>If any error occurs (e.g., malformed operands, stack underflow), an exception is thrown.</li>
+ * </ul>
  */
 public class CallCommand implements Command {
 
+    /**
+     * Executes the CALL instruction, initiating a subroutine/function call within the virtual machine.
+     * <p>
+     * This method handles the creation of a new stack frame for the callee, argument passing,
+     * and control transfer to the target function address.
+     * </p>
+     *
+     * @param parts         The instruction parameters. Must include:
+     *                      <ul>
+     *                          <li>{@code parts[0]}: The "CALL" operator.</li>
+     *                          <li>{@code parts[1]}: The target address of the callee function.</li>
+     *                          <li>{@code parts[2]}: The number of arguments to pass.</li>
+     *                      </ul>
+     * @param currentPC     The current program counter, used to record the return address for after the call.
+     * @param operandStack  The operand stack manager. Arguments are popped from this stack.
+     * @param callerLVS     The local variable store of the caller function (not directly modified here).
+     * @param callStack     The virtual machine's call stack manager, used to push the new stack frame.
+     * @return The new program counter value, which is the address of the callee function (i.e., jump target).
+     *         The VM should transfer control to this address after setting up the call frame.
+     * @throws IllegalArgumentException If the instruction parameters are malformed or missing.
+     * @throws IllegalStateException    If the operand stack does not contain enough arguments.
+     */
     @Override
     public int execute(String[] parts,
                        int currentPC,

From 6098a290b1d67686df16098ac4dc6f88ea111378 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:18:30 +0800
Subject: [PATCH 25/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=20R=5FLOAD?=
 =?UTF-8?q?=E6=8C=87=E4=BB=A4=E7=9A=84=E5=AE=9E=E7=8E=B0?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 新增 RLoadCommand 类，实现 Command接口
- 该指令用于从局部变量表中加载引用对象，并将其推入操作数栈- 指令格式：R_LOAD <slot>
- 其中 <slot> 是局部变量表中的索引
- 执行过程包括解析索引、获取引用、推入栈顶和更新程序计数器
---
 .../vm/commands/ref/control/RLoadCommand.java | 54 +++++++++++++++++++
 1 file changed, 54 insertions(+)
 create mode 100644 src/main/java/org/jcnc/snow/vm/commands/ref/control/RLoadCommand.java

diff --git a/src/main/java/org/jcnc/snow/vm/commands/ref/control/RLoadCommand.java b/src/main/java/org/jcnc/snow/vm/commands/ref/control/RLoadCommand.java
new file mode 100644
index 0000000..d7e314d
--- /dev/null
+++ b/src/main/java/org/jcnc/snow/vm/commands/ref/control/RLoadCommand.java
@@ -0,0 +1,54 @@
+package org.jcnc.snow.vm.commands.ref.control;
+
+import org.jcnc.snow.vm.interfaces.Command;
+import org.jcnc.snow.vm.module.CallStack;
+import org.jcnc.snow.vm.module.LocalVariableStore;
+import org.jcnc.snow.vm.module.OperandStack;
+
+/**
+ * The {@code RLoadCommand} class implements the {@link Command} interface and represents the
+ * reference load instruction ({@code R_LOAD}) in the virtual machine.
+ *
+ * <p>
+ * This instruction loads a reference object from the current stack frame’s local variable store
+ * at the specified slot and pushes it onto the operand stack.
+ * </p>
+ *
+ * <p>Instruction format: {@code R_LOAD <slot>}</p>
+ * <ul>
+ *   <li>{@code <slot>}: The index in the local variable table to load the reference from.</li>
+ * </ul>
+ *
+ * <p>Behavior:</p>
+ * <ul>
+ *   <li>Parses the slot index from the instruction parameters.</li>
+ *   <li>Fetches the reference object stored at the specified slot in the current stack frame's local variable store.</li>
+ *   <li>Pushes the fetched reference onto the operand stack.</li>
+ *   <li>Increments the program counter to the next instruction.</li>
+ * </ul>
+ */
+public final class RLoadCommand implements Command {
+
+    /**
+     * Executes the {@code R_LOAD} instruction, loading a reference from the local variable table and pushing it onto the operand stack.
+     *
+     * @param parts The instruction parameters. {@code parts[0]} is the operator ("R_LOAD"), {@code parts[1]} is the slot index.
+     * @param pc The current program counter value, indicating the instruction address being executed.
+     * @param stack The operand stack manager. The loaded reference will be pushed onto this stack.
+     * @param lvs The local variable store. (Not used directly, as this command uses the store from the current stack frame.)
+     * @param cs The call stack manager. The reference will be loaded from the local variable store of the top stack frame.
+     * @return The next program counter value ({@code pc + 1}), pointing to the next instruction.
+     * @throws NumberFormatException if the slot parameter cannot be parsed as an integer.
+     */
+    @Override
+    public int execute(String[] parts, int pc,
+                       OperandStack stack,
+                       LocalVariableStore lvs,
+                       CallStack cs) {
+
+        int slot = Integer.parseInt(parts[1]);
+        Object v = cs.peekFrame().getLocalVariableStore().getVariable(slot);
+        stack.push(v);
+        return pc + 1;
+    }
+}

From a7117717bd76ef791fa565e9e990336c4e10e8fa Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:19:05 +0800
Subject: [PATCH 26/36] =?UTF-8?q?refactor:=20=E6=9B=B4=E6=96=B0=E5=91=BD?=
 =?UTF-8?q?=E4=BB=A4=E5=B7=A5=E5=8E=82=E4=B8=AD=E7=9A=84=E5=BC=95=E7=94=A8?=
 =?UTF-8?q?=E5=91=BD=E4=BB=A4=E8=B7=AF=E5=BE=84?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 将 RLoadCommand、RPushCommand 和 RStoreCommand 的导入路径从 type.control.ref 改为 ref.control
- 这个改动统一了引用类型命令的包结构，与其他类型命令保持一致
---
 .../java/org/jcnc/snow/vm/factories/CommandFactory.java     | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java b/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
index 71479a3..fc4a3ed 100644
--- a/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
+++ b/src/main/java/org/jcnc/snow/vm/factories/CommandFactory.java
@@ -6,9 +6,9 @@ import org.jcnc.snow.vm.commands.type.control.double64.*;
 import org.jcnc.snow.vm.commands.type.control.float32.*;
 import org.jcnc.snow.vm.commands.type.control.int32.*;
 import org.jcnc.snow.vm.commands.type.control.long64.*;
-import org.jcnc.snow.vm.commands.type.control.ref.RLoadCommand;
-import org.jcnc.snow.vm.commands.type.control.ref.RPushCommand;
-import org.jcnc.snow.vm.commands.type.control.ref.RStoreCommand;
+import org.jcnc.snow.vm.commands.ref.control.RLoadCommand;
+import org.jcnc.snow.vm.commands.ref.control.RPushCommand;
+import org.jcnc.snow.vm.commands.ref.control.RStoreCommand;
 import org.jcnc.snow.vm.commands.type.control.short16.*;
 import org.jcnc.snow.vm.commands.type.control.byte8.BAndCommand;
 import org.jcnc.snow.vm.commands.type.control.byte8.BOrCommand;

From 5ef36d57009702a38722c6af72fa94ae5ff0778b Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:23:43 +0800
Subject: [PATCH 27/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=20R=5FPUSH?=
 =?UTF-8?q?=E6=8C=87=E4=BB=A4=E7=B1=BB?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 新增 RPushCommand 类实现 Command 接口，用于处理引用类型推入操作
- 支持将字符串字面量等引用类型数据推入操作栈
---
 .../vm/commands/ref/control/RPushCommand.java | 63 +++++++++++++++++++
 1 file changed, 63 insertions(+)
 create mode 100644 src/main/java/org/jcnc/snow/vm/commands/ref/control/RPushCommand.java

diff --git a/src/main/java/org/jcnc/snow/vm/commands/ref/control/RPushCommand.java b/src/main/java/org/jcnc/snow/vm/commands/ref/control/RPushCommand.java
new file mode 100644
index 0000000..1386018
--- /dev/null
+++ b/src/main/java/org/jcnc/snow/vm/commands/ref/control/RPushCommand.java
@@ -0,0 +1,63 @@
+package org.jcnc.snow.vm.commands.ref.control;
+
+import org.jcnc.snow.vm.interfaces.Command;
+import org.jcnc.snow.vm.module.CallStack;
+import org.jcnc.snow.vm.module.LocalVariableStore;
+import org.jcnc.snow.vm.module.OperandStack;
+
+/**
+ * The {@code RPushCommand} class implements the {@link Command} interface and represents the
+ * reference push instruction ({@code R_PUSH}) in the virtual machine.
+ *
+ * <p>
+ * This instruction pushes a reference object, such as a String literal, onto the operand stack.
+ * </p>
+ *
+ * <p>Instruction format: {@code R_PUSH <literal>}</p>
+ * <ul>
+ *   <li>{@code <literal>}: The reference value (e.g., string) to be pushed onto the stack.
+ *   If the literal contains spaces, all parts after {@code R_PUSH} are joined into a single string.</li>
+ * </ul>
+ *
+ * <p>Behavior:</p>
+ * <ul>
+ *   <li>Checks that the instruction has at least one parameter after the operator.</li>
+ *   <li>Concatenates all parameters after {@code R_PUSH} into a single string (separated by spaces).</li>
+ *   <li>Pushes the resulting string as a reference object onto the operand stack.</li>
+ *   <li>Increments the program counter to the next instruction.</li>
+ *   <li>Throws an {@code IllegalStateException} if the instruction is missing required parameters.</li>
+ * </ul>
+ */
+public final class RPushCommand implements Command {
+
+    /**
+     * Executes the {@code R_PUSH} instruction, pushing a reference (such as a string literal)
+     * onto the operand stack.
+     *
+     * @param parts The instruction parameters. {@code parts[0]} is the operator ("R_PUSH"),
+     *              {@code parts[1..]} are the parts of the literal to be concatenated and pushed.
+     * @param pc    The current program counter value, indicating the instruction address being executed.
+     * @param stack The operand stack manager. The literal will be pushed onto this stack.
+     * @param lvs   The local variable store. (Not used in this instruction.)
+     * @param cs    The call stack manager. (Not used in this instruction.)
+     * @return The next program counter value ({@code pc + 1}), pointing to the next instruction.
+     * @throws IllegalStateException if the instruction is missing required parameters.
+     */
+    @Override
+    public int execute(String[] parts, int pc,
+                       OperandStack stack,
+                       LocalVariableStore lvs,
+                       CallStack cs) {
+
+        if (parts.length < 2)
+            throw new IllegalStateException("R_PUSH missing parameter");
+
+        StringBuilder sb = new StringBuilder();
+        for (int i = 1; i < parts.length; i++) {
+            if (i > 1) sb.append(' ');
+            sb.append(parts[i]);
+        }
+        stack.push(sb.toString());
+        return pc + 1;
+    }
+}

From 33d89e99083f8244896d2e752c8a1b094caf54cb Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:24:57 +0800
Subject: [PATCH 28/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=20R=5FSTORE?=
 =?UTF-8?q?=E6=8C=87=E4=BB=A4=E7=9A=84=E5=AE=9E=E7=8E=B0?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 新增 RStoreCommand 类，实现 Command接口
- 添加 R_STORE指令的执行逻辑
- 更新虚拟机的指令集，支持 R_STORE 指令
---
 .../commands/ref/control/RStoreCommand.java   | 58 +++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 src/main/java/org/jcnc/snow/vm/commands/ref/control/RStoreCommand.java

diff --git a/src/main/java/org/jcnc/snow/vm/commands/ref/control/RStoreCommand.java b/src/main/java/org/jcnc/snow/vm/commands/ref/control/RStoreCommand.java
new file mode 100644
index 0000000..0237908
--- /dev/null
+++ b/src/main/java/org/jcnc/snow/vm/commands/ref/control/RStoreCommand.java
@@ -0,0 +1,58 @@
+package org.jcnc.snow.vm.commands.ref.control;
+
+import org.jcnc.snow.vm.interfaces.Command;
+import org.jcnc.snow.vm.module.CallStack;
+import org.jcnc.snow.vm.module.LocalVariableStore;
+import org.jcnc.snow.vm.module.OperandStack;
+
+/**
+ * The {@code RStoreCommand} class implements the {@link Command} interface and represents the
+ * reference store instruction ({@code R_STORE}) in the virtual machine.
+ *
+ * <p>
+ * This instruction pops a reference object from the top of the operand stack
+ * and stores it in the local variable table at the specified slot index of the current stack frame.
+ * </p>
+ *
+ * <p>Instruction format: {@code R_STORE <slot>}</p>
+ * <ul>
+ *   <li>{@code <slot>}: The index in the local variable table where the reference will be stored.</li>
+ * </ul>
+ *
+ * <p>Behavior:</p>
+ * <ul>
+ *   <li>Parses the slot index from the instruction parameters.</li>
+ *   <li>Pops a reference object from the operand stack.</li>
+ *   <li>Stores the popped reference object into the local variable table of the current stack frame at the specified slot.</li>
+ *   <li>Increments the program counter to the next instruction.</li>
+ *   <li>If the operand stack is empty, a {@code java.util.EmptyStackException} may be thrown.</li>
+ * </ul>
+ */
+public final class RStoreCommand implements Command {
+
+    /**
+     * Executes the {@code R_STORE} instruction, storing a reference object from the top of the operand stack
+     * into the local variable table of the current stack frame.
+     *
+     * @param parts The instruction parameters. {@code parts[0]} is the operator ("R_STORE"),
+     *              {@code parts[1]} is the slot index.
+     * @param pc    The current program counter value, indicating the instruction address being executed.
+     * @param stack The operand stack manager. The reference object will be popped from this stack.
+     * @param lvs   The local variable store. (Not used directly, as the store from the current stack frame is used.)
+     * @param cs    The call stack manager. The reference will be stored in the local variable store of the top stack frame.
+     * @return The next program counter value ({@code pc + 1}), pointing to the next instruction.
+     * @throws NumberFormatException if the slot parameter cannot be parsed as an integer.
+     * @throws java.util.EmptyStackException if the operand stack is empty when popping.
+     */
+    @Override
+    public int execute(String[] parts, int pc,
+                       OperandStack stack,
+                       LocalVariableStore lvs,
+                       CallStack cs) {
+
+        int slot = Integer.parseInt(parts[1]);
+        Object v = stack.pop();
+        cs.peekFrame().getLocalVariableStore().setVariable(slot, v);
+        return pc + 1;
+    }
+}

From b30b6aeaaa166414839063f2b26503c22dd44466 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 17:26:42 +0800
Subject: [PATCH 29/36] =?UTF-8?q?feat:=20=E6=B7=BB=E5=8A=A0=E5=BC=95?=
 =?UTF-8?q?=E7=94=A8=E7=B1=BB=E5=9E=8B=E6=8E=A7=E5=88=B6=E6=8C=87=E4=BB=A4?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 新增 R_PUSH、R_LOAD 和 R_STORE 指令，用于处理对象引用类型
- 这些指令分别用于推送、加载和存储对象引用到操作栈或本地变量表
---
 .../org/jcnc/snow/vm/engine/VMOpCode.java     | 71 +++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java b/src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java
index 8e1a880..c333e34 100644
--- a/src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java
+++ b/src/main/java/org/jcnc/snow/vm/engine/VMOpCode.java
@@ -1,5 +1,8 @@
 package org.jcnc.snow.vm.engine;
 
+import org.jcnc.snow.vm.commands.ref.control.RLoadCommand;
+import org.jcnc.snow.vm.commands.ref.control.RPushCommand;
+import org.jcnc.snow.vm.commands.ref.control.RStoreCommand;
 import org.jcnc.snow.vm.commands.system.control.SyscallCommand;
 import org.jcnc.snow.vm.commands.type.control.byte8.*;
 import org.jcnc.snow.vm.commands.type.control.double64.*;
@@ -2483,6 +2486,74 @@ public class VMOpCode {
     // endregion Double64
     // endregion Conversion
 
+    // region Reference Control (0x00E0-0x00EF)
+        /**
+         * R_PUSH Opcode: Represents an operation that pushes an object reference (such as a String or any reference type)
+         * onto the operand stack.
+         * <p>This opcode is implemented by the {@link RPushCommand} class, which defines its specific execution logic.</p>
+         *
+         * <p>Execution Steps:</p>
+         * <ol>
+         *     <li>Parses the object reference literal (e.g., a string) from the instruction parameters.</li>
+         *     <li>Creates or interprets the reference as an object instance if necessary.</li>
+         *     <li>Pushes the reference object onto the operand stack.</li>
+         *     <li>Increments the program counter (PC) to proceed with the next sequential instruction.</li>
+         * </ol>
+         *
+         * <p>This opcode is commonly used for:</p>
+         * <ul>
+         *     <li>Pushing string literals, objects, or other references needed for subsequent operations.</li>
+         *     <li>Supplying parameters for method calls that expect reference types.</li>
+         *     <li>Initializing the operand stack with reference values for computation or storage.</li>
+         * </ul>
+         */
+        public static final int R_PUSH  = 0x00E0;
+        /**
+         * R_LOAD Opcode: Represents an operation that loads an object reference from the local variable table
+         * and pushes it onto the operand stack.
+         * <p>This opcode is implemented by the {@link RLoadCommand} class, which defines its specific execution logic.</p>
+         *
+         * <p>Execution Steps:</p>
+         * <ol>
+         *     <li>Parses the target slot index from the instruction parameters.</li>
+         *     <li>Retrieves the reference object stored at the specified slot in the local variable table
+         *         of the current stack frame.</li>
+         *     <li>Pushes the retrieved reference onto the operand stack.</li>
+         *     <li>Increments the program counter (PC) to proceed with the next sequential instruction.</li>
+         * </ol>
+         *
+         * <p>This opcode is commonly used for:</p>
+         * <ul>
+         *     <li>Accessing local variables (such as function arguments or local object references) during method execution.</li>
+         *     <li>Preparing reference values for operations or method invocations.</li>
+         *     <li>Reusing objects previously stored in local variables.</li>
+         * </ul>
+         */
+        public static final int R_LOAD  = 0x00E1;
+        /**
+         * R_STORE Opcode: Represents an operation that pops an object reference from the top of the operand stack
+         * and stores it into the local variable table at the specified slot index.
+         * <p>This opcode is implemented by the {@link RStoreCommand} class, which defines its specific execution logic.</p>
+         *
+         * <p>Execution Steps:</p>
+         * <ol>
+         *     <li>Parses the target slot index from the instruction parameters.</li>
+         *     <li>Pops the top reference object from the operand stack.</li>
+         *     <li>Stores the popped reference object into the specified slot in the local variable table
+         *         of the current stack frame.</li>
+         *     <li>Increments the program counter (PC) to proceed with the next sequential instruction.</li>
+         * </ol>
+         *
+         * <p>This opcode is commonly used for:</p>
+         * <ul>
+         *     <li>Storing computation results or intermediate reference values for later use.</li>
+         *     <li>Passing object references to local variables in preparation for further operations or method calls.</li>
+         *     <li>Managing object lifetimes and ensuring correct referencing in scoped execution contexts.</li>
+         * </ul>
+         */
+        public static final int R_STORE = 0x00E2;
+    // endregion
+
     // region Stack Control (0x0100-0x01FF)
     /**
      * POP Opcode: Represents a stack operation that removes the top element from the operand stack.

From a454eed26fd825969862d431b4fa5f900350be5b Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 22:52:40 +0800
Subject: [PATCH 30/36] =?UTF-8?q?test:=20=E9=87=8D=E6=9E=84=20Demo14=20?=
 =?UTF-8?q?=E6=BC=94=E7=A4=BA=E4=BB=A3=E7=A0=81=20-=20=E7=A7=BB=E9=99=A4?=
 =?UTF-8?q?=E4=BA=86=20Main.snow=20=E6=96=87=E4=BB=B6=E4=B8=AD=E7=9A=84?=
 =?UTF-8?q?=E7=9B=B4=E6=8E=A5=E7=B3=BB=E7=BB=9F=E8=B0=83=E7=94=A8=20-=20?=
 =?UTF-8?q?=E6=96=B0=E5=A2=9E=20OS.snow=20=E6=96=87=E4=BB=B6=EF=BC=8C?=
 =?UTF-8?q?=E5=AE=9E=E7=8E=B0=20print=20=E5=87=BD=E6=95=B0=E5=B0=81?=
 =?UTF-8?q?=E8=A3=85=20-=20=E4=BF=AE=E6=94=B9=20Main.snow=EF=BC=8C?=
 =?UTF-8?q?=E4=BD=BF=E7=94=A8=E6=96=B0=E7=9A=84=20print=20=E5=87=BD?=
 =?UTF-8?q?=E6=95=B0=E6=9B=BF=E4=BB=A3=E7=B3=BB=E7=BB=9F=E8=B0=83=E7=94=A8?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 playground/Demo/Demo14/Main.snow |  3 +--
 playground/Demo/Demo14/OS.snow   | 11 +++++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)
 create mode 100644 playground/Demo/Demo14/OS.snow

diff --git a/playground/Demo/Demo14/Main.snow b/playground/Demo/Demo14/Main.snow
index 8e5baff..7ef2b05 100644
--- a/playground/Demo/Demo14/Main.snow
+++ b/playground/Demo/Demo14/Main.snow
@@ -1,10 +1,9 @@
 module: Main
     import: os
-
     function: main
         return_type: void
         body:
-            syscall("PRINT",2222+1)
+            print(222)
         end body
     end function
 end module
\ No newline at end of file
diff --git a/playground/Demo/Demo14/OS.snow b/playground/Demo/Demo14/OS.snow
new file mode 100644
index 0000000..f985171
--- /dev/null
+++ b/playground/Demo/Demo14/OS.snow
@@ -0,0 +1,11 @@
+module: Main
+    import: os
+    function: print
+        parameter:
+            declare i1: int
+        return_type: void
+        body:
+            syscall("PRINT",i1)
+        end body
+    end function
+end module
\ No newline at end of file

From 074f0b6809bec76c0547f0c467ead58d0e86ba68 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 22:54:49 +0800
Subject: [PATCH 31/36] =?UTF-8?q?chore:=20=E6=B7=BB=E5=8A=A0=E5=BA=93?=
 =?UTF-8?q?=E5=87=BD=E6=95=B0=E5=AE=9E=E7=8E=B0=E6=89=93=E5=8D=B0=E5=8A=9F?=
 =?UTF-8?q?=E8=83=BD?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 lib/os/OS.snow | 11 +++++++++++
 1 file changed, 11 insertions(+)
 create mode 100644 lib/os/OS.snow

diff --git a/lib/os/OS.snow b/lib/os/OS.snow
new file mode 100644
index 0000000..f985171
--- /dev/null
+++ b/lib/os/OS.snow
@@ -0,0 +1,11 @@
+module: Main
+    import: os
+    function: print
+        parameter:
+            declare i1: int
+        return_type: void
+        body:
+            syscall("PRINT",i1)
+        end body
+    end function
+end module
\ No newline at end of file

From e84aedc100f44de9646439e180ddae138f565470 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 23:13:50 +0800
Subject: [PATCH 32/36] =?UTF-8?q?test:=20=E4=BF=AE=E6=94=B9=E6=A8=A1?=
 =?UTF-8?q?=E5=9D=97=E5=90=8D=E7=A7=B0=E4=B8=BA=E5=B0=8F=E5=86=99?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 lib/os/OS.snow                 | 2 +-
 playground/Demo/Demo14/OS.snow | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/os/OS.snow b/lib/os/OS.snow
index f985171..6026d43 100644
--- a/lib/os/OS.snow
+++ b/lib/os/OS.snow
@@ -1,4 +1,4 @@
-module: Main
+module: os
     import: os
     function: print
         parameter:
diff --git a/playground/Demo/Demo14/OS.snow b/playground/Demo/Demo14/OS.snow
index f985171..6026d43 100644
--- a/playground/Demo/Demo14/OS.snow
+++ b/playground/Demo/Demo14/OS.snow
@@ -1,4 +1,4 @@
-module: Main
+module: os
     import: os
     function: print
         parameter:

From 6d79e28c51c002ffe8f12ae64589829f4a26bf26 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Mon, 21 Jul 2025 23:42:03 +0800
Subject: [PATCH 33/36] =?UTF-8?q?refactor:=20=E9=87=8D=E6=9E=84=20SyscallC?=
 =?UTF-8?q?ommand=20=E7=B1=BB=E5=B9=B6=E4=BC=98=E5=8C=96=E6=96=87=E6=A1=A3?=
 =?UTF-8?q?=E6=B3=A8=E9=87=8A-=20=E9=87=8D=E6=96=B0=E7=BB=84=E7=BB=87?=
 =?UTF-8?q?=E7=B1=BB=E7=BB=93=E6=9E=84=EF=BC=8C=E4=BC=98=E5=8C=96=E4=BB=A3?=
 =?UTF-8?q?=E7=A0=81=E5=B8=83=E5=B1=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 更新文档注释，使其更加清晰和详细
- 优化部分方法实现，提高可读性和可维护性
---
 .../system/control/SyscallCommand.java        | 261 ++++++------------
 1 file changed, 88 insertions(+), 173 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
index eebcd28..90caf8b 100644
--- a/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
+++ b/src/main/java/org/jcnc/snow/vm/commands/system/control/SyscallCommand.java
@@ -16,53 +16,47 @@ import java.util.*;
 import static java.nio.file.StandardOpenOption.*;
 
 /**
- * {@code SyscallCommand} —— I/O syscall 子命令集合指令。
+ * SyscallCommand —— 虚拟机系统调用（SYSCALL）指令实现。
  *
  * <p>
- * 封装类 UNIX 文件描述符（File Descriptor, FD）操作、文件/网络 I/O、管道、fd 复制、多路复用（select）等系统调用能力，
- * 基于 Java NIO 统一实现，供虚拟机指令集以 SYSCALL 形式扩展使用。
+ * 本类负责将虚拟机指令集中的 SYSCALL 进行分派，模拟现实系统常见的文件、网络、管道、标准输出等操作，
+ * 通过操作数栈完成参数、返回值传递，并借助文件描述符表（FDTable）进行底层资源管理。
+ * 所有 I/O 相关功能均基于 Java NIO 实现，兼容多种 I/O 场景。
  * </p>
  *
- * <b>栈操作约定：</b>
+ * <p>参数与栈约定:</p>
  * <ul>
- *   <li>参数按“右值先入栈、左值后入栈”的顺序推入操作数栈，执行 {@code SYSCALL <SUBCMD>} 后出栈。</li>
- *   <li>即：调用 SYSCALL OPEN path flags mode，入栈顺序为 path（先入）→ flags → mode（后入），出栈时 mode→flags→path 弹出。</li>
+ *   <li>所有调用参数，均按“右值先入、左值后入”顺序压入 {@link OperandStack}。</li>
+ *   <li>SYSCALL 指令自动弹出参数并处理结果；返回值（如描述符、读取长度、是否成功等）压回栈顶。</li>
  * </ul>
  *
- * <b>返回值说明：</b>
+ * <p>异常与失败处理:</p>
  * <ul>
- *   <li>成功：压入正值（如 FD、实际数据、字节数、0 表示成功）。</li>
- *   <li>失败：统一压入 -1，后续可扩展为 errno 机制。</li>
+ *   <li>系统调用失败或遇到异常时，均向操作数栈压入 {@code -1}，以便调用者统一检测。</li>
  * </ul>
  *
- * <b>支持的子命令（部分）：</b>
+ * <p>支持的子命令示例:</p>
  * <ul>
  *   <li>PRINT / PRINTLN —— 控制台输出</li>
- *   <li>OPEN / CLOSE / READ / WRITE / SEEK —— 文件 I/O 操作</li>
- *   <li>PIPE / DUP —— 管道和 FD 复制</li>
- *   <li>SOCKET / CONNECT / BIND / LISTEN / ACCEPT —— 网络套接字</li>
- *   <li>SELECT —— I/O 多路复用</li>
+ *   <li>OPEN / CLOSE / READ / WRITE / SEEK —— 文件相关操作</li>
+ *   <li>PIPE / DUP —— 管道与文件描述符复制</li>
+ *   <li>SOCKET / CONNECT / BIND / LISTEN / ACCEPT —— 网络通信</li>
+ *   <li>SELECT —— 多通道 I/O 就绪检测</li>
  * </ul>
  */
 public class SyscallCommand implements Command {
 
-
-
-    /*--------------------------------------------------------------------------------*/
-
     /**
-     * <b>执行 SYSCALL 子命令</b>：
-     * <p>
-     * 按照 parts[1] 指定的 SYSCALL 子命令，结合虚拟机栈与资源表完成对应的系统调用模拟。
-     * 支持基础文件、网络、管道等 I/O 操作，并对异常统一处理。
-     * </p>
+     * 分发并执行 SYSCALL 子命令，根据子命令类型从操作数栈取出参数、操作底层资源，并将结果压回栈顶。
      *
-     * @param parts     指令字符串数组，parts[1] 为子命令
+     * @param parts     指令及子命令参数分割数组，parts[1]为子命令名
      * @param pc        当前指令计数器
      * @param stack     操作数栈
      * @param locals    局部变量表
      * @param callStack 调用栈
-     * @return 下一条指令的 pc 值（默认 pc+1）
+     * @return 下一条指令的 pc 值（通常为 pc+1）
+     * @throws IllegalArgumentException      缺少子命令参数时抛出
+     * @throws UnsupportedOperationException 不支持的 SYSCALL 子命令时抛出
      */
     @Override
     public int execute(String[] parts, int pc,
@@ -70,46 +64,27 @@ public class SyscallCommand implements Command {
                        LocalVariableStore locals,
                        CallStack callStack) {
 
-        if (parts.length < 2)
-            throw new IllegalArgumentException("SYSCALL needs sub-command");
+        if (parts.length < 2) {
+            throw new IllegalArgumentException("SYSCALL missing subcommand");
+        }
 
         String cmd = parts[1].toUpperCase(Locale.ROOT);
 
         try {
             switch (cmd) {
-
-                /*==================== 文件 / 目录 ====================*/
-
-                /*
-                 * OPEN —— 打开文件，返回文件描述符（File Descriptor, FD）。
-                 * 入栈（push）顺序: path（文件路径, String）, flags（int）, mode（int，文件权限，暂未用）
-                 * 出栈（pop）顺序: mode → flags → path
-                 * 成功返回 fd，失败返回 -1。
-                 */
+                // 文件相关操作
                 case "OPEN" -> {
-                    int mode = (Integer) stack.pop();      // 目前未用
+                    int mode = (Integer) stack.pop();
                     int flags = (Integer) stack.pop();
                     String path = String.valueOf(stack.pop());
                     FileChannel fc = FileChannel.open(Paths.get(path), flagsToOptions(flags));
                     stack.push(FDTable.register(fc));
                 }
-                /*
-                 * CLOSE —— 关闭文件描述符。
-                 * 入栈顺序: fd（int）
-                 * 出栈顺序: fd
-                 * 返回 0 成功，-1 失败
-                 */
                 case "CLOSE" -> {
                     int fd = (Integer) stack.pop();
                     FDTable.close(fd);
                     stack.push(0);
                 }
-                /*
-                 * READ —— 从 fd 读取指定字节数。
-                 * 入栈顺序: fd（int）, count（int，字节数）
-                 * 出栈顺序: count → fd
-                 * 返回：byte[]（实际读取的数据，EOF 时长度为 0）
-                 */
                 case "READ" -> {
                     int count = (Integer) stack.pop();
                     int fd = (Integer) stack.pop();
@@ -126,12 +101,6 @@ public class SyscallCommand implements Command {
                     buf.get(out);
                     stack.push(out);
                 }
-                /*
-                 * WRITE —— 向 fd 写数据。
-                 * 入栈顺序: fd（int）, data（byte[] 或 String）
-                 * 出栈顺序: data → fd
-                 * 返回写入字节数，失败 -1
-                 */
                 case "WRITE" -> {
                     Object dataObj = stack.pop();
                     int fd = (Integer) stack.pop();
@@ -146,12 +115,6 @@ public class SyscallCommand implements Command {
                     int written = wch.write(ByteBuffer.wrap(data));
                     stack.push(written);
                 }
-                /*
-                 * SEEK —— 文件定位，移动文件读写指针。
-                 * 入栈顺序: fd（int）, offset（long/int）, whence（int, 0=SET,1=CUR,2=END）
-                 * 出栈顺序: whence → offset → fd
-                 * 返回新位置（long），失败 -1
-                 */
                 case "SEEK" -> {
                     int whence = (Integer) stack.pop();
                     long off = ((Number) stack.pop()).longValue();
@@ -165,58 +128,32 @@ public class SyscallCommand implements Command {
                         case 0 -> sbc.position(off);
                         case 1 -> sbc.position(sbc.position() + off);
                         case 2 -> sbc.position(sbc.size() + off);
-                        default -> throw new IllegalArgumentException("bad whence");
+                        default -> throw new IllegalArgumentException("Invalid offset type");
                     };
                     stack.push(newPos);
                 }
 
-                /*==================== 管道 / FD 相关 ====================*/
-
-                /*
-                 * PIPE —— 创建匿名管道。
-                 * 入栈顺序: （无）
-                 * 出栈顺序: （无）
-                 * 返回顺序: write fd（先压栈），read fd（后压栈）
-                 */
+                // 管道与描述符操作
                 case "PIPE" -> {
                     Pipe p = Pipe.open();
-                    stack.push(FDTable.register(p.sink()));   // write fd
-                    stack.push(FDTable.register(p.source())); // read fd
+                    stack.push(FDTable.register(p.sink()));
+                    stack.push(FDTable.register(p.source()));
                 }
-                /*
-                 * DUP —— 复制一个已存在的 fd（dup）。
-                 * 入栈顺序: oldfd（int）
-                 * 出栈顺序: oldfd
-                 * 返回新的 fd，失败 -1
-                 */
                 case "DUP" -> {
                     int oldfd = (Integer) stack.pop();
                     stack.push(FDTable.dup(oldfd));
                 }
 
-                /*==================== 网络相关 ====================*/
-
-                /*
-                 * SOCKET —— 创建套接字，支持 stream/dgram。
-                 * 入栈顺序: domain（int, AF_INET=2等）, type（int, 1=STREAM,2=DGRAM）, protocol（int, 预留）
-                 * 出栈顺序: protocol → type → domain
-                 * 返回 fd
-                 */
+                // 网络相关
                 case "SOCKET" -> {
-                    int proto = (Integer) stack.pop();      // 预留，暂不用
-                    int type = (Integer) stack.pop();       // 1=STREAM,2=DGRAM
-                    int domain = (Integer) stack.pop();     // AF_INET=2……
+                    int proto = (Integer) stack.pop();
+                    int type = (Integer) stack.pop();
+                    int domain = (Integer) stack.pop();
                     Channel ch = (type == 1)
                             ? SocketChannel.open()
                             : DatagramChannel.open();
                     stack.push(FDTable.register(ch));
                 }
-                /*
-                 * CONNECT —— 发起 TCP 连接。
-                 * 入栈顺序: fd（int）, host（String）, port（int）
-                 * 出栈顺序: port → host → fd
-                 * 返回 0 成功，-1 失败
-                 */
                 case "CONNECT" -> {
                     int port = (Integer) stack.pop();
                     String host = String.valueOf(stack.pop());
@@ -225,14 +162,10 @@ public class SyscallCommand implements Command {
                     if (ch instanceof SocketChannel sc) {
                         sc.connect(new InetSocketAddress(host, port));
                         stack.push(0);
-                    } else stack.push(-1);
+                    } else {
+                        stack.push(-1);
+                    }
                 }
-                /*
-                 * BIND —— 绑定端口。
-                 * 入栈顺序: fd（int）, host（String）, port（int）
-                 * 出栈顺序: port → host → fd
-                 * 返回 0 成功，-1 失败
-                 */
                 case "BIND" -> {
                     int port = (Integer) stack.pop();
                     String host = String.valueOf(stack.pop());
@@ -241,45 +174,32 @@ public class SyscallCommand implements Command {
                     if (ch instanceof ServerSocketChannel ssc) {
                         ssc.bind(new InetSocketAddress(host, port));
                         stack.push(0);
-                    } else stack.push(-1);
+                    } else {
+                        stack.push(-1);
+                    }
                 }
-                /*
-                 * LISTEN —— 监听 socket，兼容 backlog。
-                 * 入栈顺序: fd（int）, backlog（int）
-                 * 出栈顺序: backlog → fd
-                 * 返回 0 成功，-1 失败
-                 * <b>注意：Java NIO 打开 ServerSocketChannel 已自动监听，无 backlog 处理，行为和 UNIX 有区别。</b>
-                 */
                 case "LISTEN" -> {
                     int backlog = (Integer) stack.pop();
                     int fd = (Integer) stack.pop();
                     Channel ch = FDTable.get(fd);
-                    if (ch instanceof ServerSocketChannel) stack.push(0);
-                    else stack.push(-1);
+                    if (ch instanceof ServerSocketChannel) {
+                        stack.push(0);
+                    } else {
+                        stack.push(-1);
+                    }
                 }
-                /*
-                 * ACCEPT —— 接收连接。
-                 * 入栈顺序: fd（int）
-                 * 出栈顺序: fd
-                 * 返回新连接 fd，失败 -1
-                 */
                 case "ACCEPT" -> {
                     int fd = (Integer) stack.pop();
                     Channel ch = FDTable.get(fd);
                     if (ch instanceof ServerSocketChannel ssc) {
                         SocketChannel cli = ssc.accept();
                         stack.push(FDTable.register(cli));
-                    } else stack.push(-1);
+                    } else {
+                        stack.push(-1);
+                    }
                 }
 
-                /*==================== 多路复用 ====================*/
-
-                /*
-                 * SELECT —— I/O 多路复用，监视多个 fd 是否可读写。
-                 * 入栈顺序: fds（List<Integer>）, timeout_ms（long）
-                 * 出栈顺序: timeout_ms → fds
-                 * 返回: 就绪 fd 列表（List<Integer>）
-                 */
+                // 多路复用
                 case "SELECT" -> {
                     long timeout = ((Number) stack.pop()).longValue();
                     @SuppressWarnings("unchecked")
@@ -298,107 +218,94 @@ public class SyscallCommand implements Command {
                     int ready = sel.select(timeout);
                     List<Integer> readyFds = new ArrayList<>();
                     if (ready > 0) {
-                        for (SelectionKey k : sel.selectedKeys())
+                        for (SelectionKey k : sel.selectedKeys()) {
                             readyFds.add((Integer) k.attachment());
+                        }
                     }
                     stack.push(readyFds);
                     sel.close();
                 }
 
-
-                /*==================== 控制台输出 ====================*/
-
-                /*
-                 * PRINT —— 控制台输出（无换行）。
-                 * 入栈顺序: data（任意基本类型或其包装类型、String、byte[] 等）
-                 * 出栈顺序: data
-                 * 返回 0
-                 */
+                // 控制台输出
                 case "PRINT" -> {
                     Object dataObj = stack.pop();
                     output(dataObj, false);
-                    stack.push(0); // success
+                    stack.push(0);
                 }
-
-                /* PRINTLN —— 控制台输出（自动换行）。*/
                 case "PRINTLN" -> {
                     Object dataObj = stack.pop();
                     output(dataObj, true);
-                    stack.push(0); // success
+                    stack.push(0);
                 }
 
-
-                /*==================== 其它未实现/扩展命令 ====================*/
-
-                /*
-                 * 其它自定义 syscall 子命令未实现
-                 */
-                default -> throw new UnsupportedOperationException("Unsupported SYSCALL: " + cmd);
+                default -> throw new UnsupportedOperationException("Unsupported SYSCALL subcommand: " + cmd);
             }
         } catch (Exception e) {
-            // 统一异常处理，异常时压入 -1
             pushErr(stack, e);
         }
 
-        // 默认：下一条指令
         return pc + 1;
     }
 
-    /*------------------------------------ 工具方法 ------------------------------------*/
-
     /**
-     * <b>POSIX open 标志到 Java NIO OpenOption 的映射</b>
+     * 根据传入的文件打开标志，构造 NIO {@link OpenOption} 集合。
      * <p>
-     * 将 Linux/UNIX 的 open 调用 flags 参数，转换为 Java NIO 的 OpenOption 集合。
-     * 目前仅支持 WRITE（0x1）、READ、CREATE（0x40）、TRUNCATE（0x200）、APPEND（0x400）等常用标志。
+     * 本方法负责将底层虚拟机传递的 flags 整数型位域，转换为 Java NIO 标准的文件打开选项集合，
+     * 以支持文件读、写、创建、截断、追加等多种访问场景。
+     * 常用于 SYSCALL 的 OPEN 子命令。
      * </p>
      *
-     * @param flags POSIX 风格 open 标志（如 O_WRONLY=0x1, O_CREAT=0x40 等）
-     * @return 映射后的 OpenOption 集合
+     * @param flags 文件打开模式标志。各标志可组合使用，具体含义请参见虚拟机文档。
+     * @return 转换后的 OpenOption 集合，可直接用于 FileChannel.open 等 NIO 方法
      */
     private static Set<OpenOption> flagsToOptions(int flags) {
         Set<OpenOption> opts = new HashSet<>();
-        // 0x1 = WRITE，否则默认 READ
+        // 如果有写入标志，则添加WRITE，否则默认为READ。
         if ((flags & 0x1) != 0) opts.add(WRITE);
         else opts.add(READ);
+        // 如果包含创建标志，允许创建文件。
         if ((flags & 0x40) != 0) opts.add(CREATE);
+        // 包含截断标志，打开时清空内容。
         if ((flags & 0x200) != 0) opts.add(TRUNCATE_EXISTING);
+        // 包含追加标志，文件写入时追加到末尾。
         if ((flags & 0x400) != 0) opts.add(APPEND);
         return opts;
     }
 
     /**
-     * <b>统一异常处理</b>：
+     * 捕获所有异常并统一处理，操作数栈压入 -1 代表本次系统调用失败。
      * <p>
-     * 捕获 syscall 内部所有异常，将 -1 压入操作数栈，表示系统调用失败（暂不区分错误类型）。
-     * 常见异常如文件不存在、权限不足、通道类型不符、网络故障等。
+     * 本方法是全局错误屏障，任何命令异常都会转换为虚拟机通用的失败信号，
+     * 保证上层调用逻辑不会被异常打断。实际应用中可拓展错误码机制。
      * </p>
      *
-     * @param stack 当前操作数栈
-     * @param e     捕获的异常对象
+     * @param stack 操作数栈，将失败信号写入此栈
+     * @param e     抛出的异常对象，可在调试时输出日志
      */
     private static void pushErr(OperandStack stack, Exception e) {
-        stack.push(-1);  // 目前统一用 -1，后续可按异常类型/errno 映射
+        stack.push(-1);
+        System.err.println("Syscall exception: " + e);
     }
 
     /**
-     * 统一的控制台输出辅助方法，支持：
-     * <ul>
-     *   <li>所有基本类型及其包装类（int、double、long、float…）</li>
-     *   <li>String、byte[]、char[] 以及其他原生数组</li>
-     *   <li>任意 Object（调用 {@code toString}）</li>
-     * </ul>
+     * 控制台输出通用方法，支持基本类型、字节数组、任意数组、对象等。
+     * <p>
+     * 该方法用于 SYSCALL PRINT/PRINTLN，将任意类型对象转为易读字符串输出到标准输出流。
+     * 字节数组自动按 UTF-8 解码，其它原生数组按格式化字符串输出。
+     * </p>
      *
-     * @param obj     要输出的对象
-     * @param newline 是否追加换行
+     * @param obj     待输出的内容，可以为任何类型（如基本类型、byte[]、数组、对象等）
+     * @param newline 是否自动换行。如果为 true，则在输出后换行；否则直接输出。
      */
     private static void output(Object obj, boolean newline) {
         String str;
         if (obj == null) {
             str = "null";
         } else if (obj instanceof byte[] bytes) {
+            // 字节数组作为文本输出
             str = new String(bytes);
         } else if (obj.getClass().isArray()) {
+            // 其它数组格式化输出
             str = arrayToString(obj);
         } else {
             str = obj.toString();
@@ -408,7 +315,15 @@ public class SyscallCommand implements Command {
     }
 
     /**
-     * 将各种原生数组转换成可读字符串。
+     * 将各种原生数组和对象数组转换为可读字符串，便于控制台输出和调试。
+     * <p>
+     * 本方法针对 int、long、double、float、short、char、byte、boolean 等所有原生数组类型
+     * 以及对象数组都能正确格式化，统一输出格式风格，避免显示为类型 hashCode。
+     * 若为不支持的类型，返回通用提示字符串。
+     * </p>
+     *
+     * @param array 任意原生数组或对象数组
+     * @return 该数组的可读字符串表示
      */
     private static String arrayToString(Object array) {
         if (array instanceof int[] a) return Arrays.toString(a);

From 07b7d5c40e6f548ea60fb6afb865d4fb3de2c258 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Tue, 22 Jul 2025 16:35:43 +0800
Subject: [PATCH 34/36] =?UTF-8?q?refactor:=20=E4=BC=98=E5=8C=96=E7=A8=8B?=
 =?UTF-8?q?=E5=BA=8F=E7=BB=88=E6=AD=A2=E5=92=8C=E5=87=BD=E6=95=B0=E8=B0=83?=
 =?UTF-8?q?=E7=94=A8=E7=9A=84=E8=BE=93=E5=87=BA=E6=A0=BC=E5=BC=8F?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 在 CallCommand 中添加换行符，改善函数调用的输出可读性
- 修改 HaltCommand 中的终止消息格式，提高信息的清晰度
---
 .../org/jcnc/snow/vm/commands/flow/control/CallCommand.java     | 2 +-
 .../org/jcnc/snow/vm/commands/system/control/HaltCommand.java   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/vm/commands/flow/control/CallCommand.java b/src/main/java/org/jcnc/snow/vm/commands/flow/control/CallCommand.java
index 1171885..26dda90 100644
--- a/src/main/java/org/jcnc/snow/vm/commands/flow/control/CallCommand.java
+++ b/src/main/java/org/jcnc/snow/vm/commands/flow/control/CallCommand.java
@@ -80,7 +80,7 @@ public class CallCommand implements Command {
                 new MethodContext("subroutine@" + targetAddr, null));
         callStack.pushFrame(newFrame);
 
-        System.out.println("Calling function at address: " + targetAddr);
+        System.out.println("\nCalling function at address: " + targetAddr);
         return targetAddr;   // jump
     }
 }
diff --git a/src/main/java/org/jcnc/snow/vm/commands/system/control/HaltCommand.java b/src/main/java/org/jcnc/snow/vm/commands/system/control/HaltCommand.java
index 06a5da4..71e208c 100644
--- a/src/main/java/org/jcnc/snow/vm/commands/system/control/HaltCommand.java
+++ b/src/main/java/org/jcnc/snow/vm/commands/system/control/HaltCommand.java
@@ -59,7 +59,7 @@ public class HaltCommand implements Command {
     @Override
     public int execute(String[] parts, int currentPC, OperandStack operandStack, LocalVariableStore localVariableStore, CallStack callStack) {
         // Output the termination message
-        LoggingUtils.logInfo("Process has ended", "\n");
+        LoggingUtils.logInfo("\nProcess has ended", "");
 
         // Return -1 to indicate the program termination, and the virtual machine will not continue executing subsequent instructions
         return -1;

From 70feb1fe5e94a771d591ad477f6b528562d6fadc Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Tue, 22 Jul 2025 16:36:23 +0800
Subject: [PATCH 35/36] =?UTF-8?q?style:=20=E4=BC=98=E5=8C=96=20RetCommand?=
 =?UTF-8?q?=20=E7=B1=BB=E7=9A=84=E8=BE=93=E5=87=BA=E6=A0=BC=E5=BC=8F?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../java/org/jcnc/snow/vm/commands/flow/control/RetCommand.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/java/org/jcnc/snow/vm/commands/flow/control/RetCommand.java b/src/main/java/org/jcnc/snow/vm/commands/flow/control/RetCommand.java
index 1e4ebd5..505f378 100644
--- a/src/main/java/org/jcnc/snow/vm/commands/flow/control/RetCommand.java
+++ b/src/main/java/org/jcnc/snow/vm/commands/flow/control/RetCommand.java
@@ -44,7 +44,7 @@ public class RetCommand implements Command {
         finished.getLocalVariableStore().clearVariables();
 
         int returnAddr = finished.getReturnAddress();
-        System.out.println("Return " + returnAddr);
+        System.out.println("\nReturn " + returnAddr);
         return returnAddr;
     }
 }

From 1605390f0863655d6b72781597bd020b8faf2f62 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Tue, 22 Jul 2025 16:37:53 +0800
Subject: [PATCH 36/36] =?UTF-8?q?fix:=20=E4=BF=AE=E5=A4=8D=E5=87=BD?=
 =?UTF-8?q?=E6=95=B0=E6=9C=AB=E5=B0=BE=20CALL=20=E6=8C=87=E4=BB=A4?=
 =?UTF-8?q?=E7=9A=84=E6=9C=AA=E8=A7=A3=E6=9E=90=E7=AC=A6=E5=8F=B7=E9=97=AE?=
 =?UTF-8?q?=E9=A2=98?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 在函数开始时登记函数入口地址
- 在函数末尾强制添加 RET 或 HALT 指令
- 优化了代码注释和格式
---
 .../backend/builder/VMCodeGenerator.java      | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/backend/builder/VMCodeGenerator.java b/src/main/java/org/jcnc/snow/compiler/backend/builder/VMCodeGenerator.java
index 8370e90..2458b9e 100644
--- a/src/main/java/org/jcnc/snow/compiler/backend/builder/VMCodeGenerator.java
+++ b/src/main/java/org/jcnc/snow/compiler/backend/builder/VMCodeGenerator.java
@@ -1,6 +1,7 @@
 package org.jcnc.snow.compiler.backend.builder;
 
 import org.jcnc.snow.compiler.backend.core.InstructionGenerator;
+import org.jcnc.snow.compiler.backend.utils.OpHelper;
 import org.jcnc.snow.compiler.ir.core.IRFunction;
 import org.jcnc.snow.compiler.ir.core.IRInstruction;
 import org.jcnc.snow.compiler.ir.value.IRVirtualRegister;
@@ -16,7 +17,7 @@ import java.util.stream.Collectors;
  * 仅负责根据指令类型分发到对应的 {@link InstructionGenerator} 子类完成实际生成。
  * </p>
  * <p>
- * 工作流程简述: 
+ * 工作流程简述:
  * <ol>
  *   <li>接收一组已注册的 IR 指令生成器，并建立类型到生成器的映射表。</li>
  *   <li>遍历 IR 函数体的每条指令，根据类型找到对应的生成器，调用其 generate 方法生成 VM 指令。</li>
@@ -74,18 +75,26 @@ public final class VMCodeGenerator {
      */
     public void generate(IRFunction fn) {
         this.currentFn = fn.name();
-        out.beginFunction(currentFn); // 输出函数起始
+
+        /* 登记函数入口地址 —— 解决 CALL 未解析符号问题 */
+        out.beginFunction(currentFn);
+
+        /* 逐条分发 IR 指令给对应的生成器 */
         for (IRInstruction ins : fn.body()) {
             @SuppressWarnings("unchecked")
-            // 取得与当前 IR 指令类型匹配的生成器（泛型强转消除类型警告）
             InstructionGenerator<IRInstruction> gen =
                     (InstructionGenerator<IRInstruction>) registry.get(ins.getClass());
             if (gen == null) {
                 throw new IllegalStateException("Unsupported IR: " + ins);
             }
-            // 通过多态分发到实际生成器
             gen.generate(ins, out, slotMap, currentFn);
         }
-        out.endFunction(); // 输出函数结束
+
+        /* 强制补上函数结尾的返回/终止指令 */
+        String retOpcode = "main".equals(currentFn) ? "HALT" : "RET";
+        out.emit(OpHelper.opcode(retOpcode));
+
+        /* 结束函数 */
+        out.endFunction();
     }
 }