diff --git a/App/lib/Phase/BuildPipeline.vp b/App/lib/Phase/BuildPipeline.vp
index 9757226..7ab4804 100644
--- a/App/lib/Phase/BuildPipeline.vp
+++ b/App/lib/Phase/BuildPipeline.vp
@@ -53,6 +53,34 @@ _phase2_cmd_path: str = None
 # bat 文件是否已写入 header（@echo off），首次写入时置 1
 _phase2_bat_init: int = 0
 
+# MLIR 后端（Config.is_mlir_backend()）降级步骤：mlirlite 发射的是 MLIR 文本，
+# 而 opt/llc 只接受 LLVM IR，故在两者之前插入：
+#   mlir-opt <in> -o <in>.mlir.opt                                  （语法/语义校验）
+#   mlir-translate --mlir-to-llvmir <in>.mlir.opt -o <in>.ll.local  （降级回 LLVM IR）
+# 降级产物 <...>.ll.local 与输入 .ll 同目录，不占用 <sha1>.ll 缓存键。
+MLIR_OPT_CMD: str = "mlir-opt"
+MLIR_TRANSLATE_CMD: str = "mlir-translate"
+
+
+def _ir_sibling_path(ir_path: str, suffix: str) -> str:
+    """由 <...>.ll 派生同目录邻居路径：去掉末尾 ".ll" 后拼 suffix（如 ".mlir.opt"）。
+
+    从 _mbuddy 分配（与 build_sliced_path 同池，随 pool reset 回收，无需手动 free）。
+    """
+    if ir_path is None or suffix is None:
+        return None
+    n: sizet = string.strlen(ir_path)
+    if n < 3:
+        return None
+    suf_len: sizet = string.strlen(suffix)
+    buf: str = _mbuddy.alloc(n + suf_len + 1)
+    if buf is None:
+        return None
+    string.strncpy(buf, ir_path, n - 3)
+    buf[n - 3] = '\0'
+    string.strcat(buf, suffix)
+    return buf
+
 # 源代码缓冲区大小（1MB）
 SRC_BUF_SIZE: t.CDefine = 1048576 # 2^20 = 1MB
 
@@ -398,18 +426,50 @@ def compile_ll_to_obj(ir_path: str, output_dir: str, module_name: str, cc_cmd: s
     # 用直接地址寻址，ASan 全局 redzone 重定位后引用错位会读到垃圾指针。
     compile_input: str = ir_path
 
+    # ---- MLIR 后端降级：mlir-opt（校验）→ mlir-translate（降级回 LLVM IR）----
+    # 必须在 ASan opt 与 llc 之前，并把 compile_input 替换为 <...>.ll.local。
+    if Config.is_mlir_backend() != 0:
+        ll_local_path: str = _ir_sibling_path(ir_path, ".ll.local")
+        mlir_opt_out: str = _ir_sibling_path(ir_path, ".mlir.opt")
+        if ll_local_path is None or mlir_opt_out is None:
+            return 1
+        mo_len: sizet = len(MLIR_OPT_CMD) + len(ir_path) + len(mlir_opt_out) + 16
+        cmd_mo: str = _mbuddy.alloc(mo_len)
+        if cmd_mo is None:
+            return 1
+        viperlib.snprintf(cmd_mo, mo_len, "%s %s -o %s", MLIR_OPT_CMD, ir_path, mlir_opt_out)
+        mt_len: sizet = len(MLIR_TRANSLATE_CMD) + len(mlir_opt_out) + len(ll_local_path) + 40
+        cmd_mt: str = _mbuddy.alloc(mt_len)
+        if cmd_mt is None:
+            return 1
+        viperlib.snprintf(cmd_mt, mt_len, "%s --mlir-to-llvmir %s -o %s", MLIR_TRANSLATE_CMD, mlir_opt_out, ll_local_path)
+        if _phase2_cmd_path is not None:
+            # 只写命令（须排在下面的 ASan/llc 命令之前）
+            _phase2_write_cmd(cmd_mo)
+            _phase2_write_cmd(cmd_mt)
+        else:
+            mo_rc: int = _run_cmd_wait(cmd_mo)
+            if mo_rc != 0:
+                VLogger.error(f"mlir-opt 失败 (module={module_name}, exit={mo_rc}, cmd={cmd_mo})", "MLIR")
+                return 1
+            mt_rc: int = _run_cmd_wait(cmd_mt)
+            if mt_rc != 0:
+                VLogger.error(f"mlir-translate 失败 (module={module_name}, exit={mt_rc}, cmd={cmd_mt})", "MLIR")
+                return 1
+        compile_input = ll_local_path
+
     # --phase2command 模式：不执行 opt/llc，把 opt（ASan）+ llc 命令写入 bat
     if _phase2_cmd_path is not None:
         p2_opt_cmd: str = None
         if _asan_mode != 0:
             p2_asan: str = build_sliced_path(output_dir, module_name, "asan.ll")
             if p2_asan is not None:
-                p2_olen: sizet = len(p2_asan) + len(ir_path) + 192
+                p2_olen: sizet = len(p2_asan) + len(compile_input) + 192
                 p2_opt_cmd = _mbuddy.alloc(p2_olen)
                 if p2_opt_cmd is not None:
                     viperlib.snprintf(p2_opt_cmd, p2_olen,
                         "opt -passes=forceattrs,asan -force-attribute=sanitize_address -asan-globals=false -o %s %s",
-                        p2_asan, ir_path)
+                        p2_asan, compile_input)
                 compile_input = p2_asan
         llc_fp: str = _llc_frame_ptr_flag()
         p2_clen: sizet = len(cc_cmd) + len(cc_flags) + len(llc_fp) + len(obj_path) + len(compile_input) + 64
@@ -427,13 +487,13 @@ def compile_ll_to_obj(ir_path: str, output_dir: str, module_name: str, cc_cmd: s
         asan_path: str = build_sliced_path(output_dir, module_name, "asan.ll")
         if asan_path is None:
             return 1
-        opt_cmd_len: sizet = len(asan_path) + len(ir_path) + 192
+        opt_cmd_len: sizet = len(asan_path) + len(compile_input) + 192
         opt_cmd: bytes = _mbuddy.alloc(opt_cmd_len)
         if opt_cmd is None:
             return 1
         viperlib.snprintf(opt_cmd, opt_cmd_len,
                           "opt -passes=forceattrs,asan -force-attribute=sanitize_address -asan-globals=false -o %s %s",
-                          asan_path, ir_path)
+                          asan_path, compile_input)
         opt_ret: int = stdlib.system(opt_cmd)
         if opt_ret != 0:
             VLogger.error(f"opt ASan 插桩失败 (module={module_name})", "ASAN")
@@ -479,6 +539,9 @@ class LlcTask:
     # ExitCode 追加在结尾：既有字段偏移不变；LlcTask.__sizeof__() 随之增大，
     # 所有构造/初始化点均按 __sizeof__() 算首址并对整条 memset，无需改偏移。
     ExitCode: int      # worker 写：失败命令退出码（成功为 0）
+    # MLIR 后端降级命令（非 MLIR 为 None）；同样追加在结尾，不影响既有偏移。
+    MlirOptCmd: bytes        # mlir-opt 校验命令
+    MlirTranslateCmd: bytes  # mlir-translate 降级命令
 
 
 def init_llc_task(task: LlcTask | t.CPtr, ir_path: str, output_dir: str,
@@ -501,20 +564,39 @@ def init_llc_task(task: LlcTask | t.CPtr, ir_path: str, output_dir: str,
     # compile_ll_to_obj 的 compile_input 同口径（否则 opt 生成了插桩产物
     # 却被 llc 忽略，App 侧 obj 里 0 处 __asan，内存排查半盲）
     compile_input: str = ir_path
-    # ASan 模式：opt 插桩命令（worker 先跑 opt 再跑 llc，故 LlcCmd 的输入
+    # MLIR 后端降级：worker 先跑 mlir-opt（校验）→ mlir-translate（降级回 LLVM IR），
+    # 之后的 ASan OptCmd / LlcCmd 输入必须是 <...>.ll.local。
+    if Config.is_mlir_backend() != 0:
+        ll_local_path: str = _ir_sibling_path(ir_path, ".ll.local")
+        mlir_opt_out: str = _ir_sibling_path(ir_path, ".mlir.opt")
+        if ll_local_path is None or mlir_opt_out is None:
+            return 1
+        mo_len: sizet = len(MLIR_OPT_CMD) + len(ir_path) + len(mlir_opt_out) + 16
+        task.MlirOptCmd = stdlib.malloc(mo_len)
+        if task.MlirOptCmd is None:
+            return 1
+        viperlib.snprintf(task.MlirOptCmd, mo_len, "%s %s -o %s", MLIR_OPT_CMD, ir_path, mlir_opt_out)
+        mt_len: sizet = len(MLIR_TRANSLATE_CMD) + len(mlir_opt_out) + len(ll_local_path) + 40
+        task.MlirTranslateCmd = stdlib.malloc(mt_len)
+        if task.MlirTranslateCmd is None:
+            return 1
+        viperlib.snprintf(task.MlirTranslateCmd, mt_len, "%s --mlir-to-llvmir %s -o %s",
+                          MLIR_TRANSLATE_CMD, mlir_opt_out, ll_local_path)
+        compile_input = ll_local_path
+    # ASan 模式：opt 插桩命令（worker 先跑 MLIR 降级/opt 再跑 llc，故 LlcCmd 的输入
     # 必须指向 asan_path；失败即置 Result）
     if _asan_mode != 0:
         asan_path: str = build_sliced_path(output_dir, module_name, "asan.ll")
         if asan_path is None:
             return 1
-        opt_len: sizet = len(asan_path) + len(ir_path) + 192
+        opt_len: sizet = len(asan_path) + len(compile_input) + 192
         task.OptCmd = stdlib.malloc(opt_len)
         if task.OptCmd is None:
             return 1
         viperlib.snprintf(task.OptCmd, opt_len,
                           "opt -passes=forceattrs,asan -force-attribute=sanitize_address"
                           " -asan-globals=false -o %s %s",
-                          asan_path, ir_path)
+                          asan_path, compile_input)
         compile_input = asan_path
     # llc 命令（输入 = compile_input：非 ASan 为 .ll，ASan 为 .asan.ll）
     llc_fp3: str = _llc_frame_ptr_flag()
@@ -538,6 +620,12 @@ def free_llc_task(task: LlcTask | t.CPtr):
     if task.LlcCmd is not None:
         stdlib.free(task.LlcCmd)
         task.LlcCmd = None
+    if task.MlirOptCmd is not None:
+        stdlib.free(task.MlirOptCmd)
+        task.MlirOptCmd = None
+    if task.MlirTranslateCmd is not None:
+        stdlib.free(task.MlirTranslateCmd)
+        task.MlirTranslateCmd = None
     if task.ModuleSha1 is not None:
         stdlib.free(task.ModuleSha1)
         task.ModuleSha1 = None
@@ -628,6 +716,19 @@ def _llc_task_worker(arg: t.CPtr) -> t.CPtr:
     task: LlcTask | t.CPtr = (LlcTask | t.CPtr)(arg)
     if task is None:
         return t.CPtr(0)
+    # MLIR 后端：先校验（mlir-opt）→ 降级（mlir-translate），再 ASan opt → llc
+    if task.MlirOptCmd is not None:
+        mo_rc: int = _run_cmd_wait(task.MlirOptCmd)
+        if mo_rc != 0:
+            task.ExitCode = mo_rc
+            task.Result = 1
+            return t.CPtr(0)
+    if task.MlirTranslateCmd is not None:
+        mt_rc: int = _run_cmd_wait(task.MlirTranslateCmd)
+        if mt_rc != 0:
+            task.ExitCode = mt_rc
+            task.Result = 1
+            return t.CPtr(0)
     if task.OptCmd is not None:
         opt_rc: int = _run_cmd_wait(task.OptCmd)
         if opt_rc != 0:
@@ -657,6 +758,10 @@ def run_llc_parallel(tasks: bytes, task_count: int, max_threads: int) -> int:
             tsk_p: LlcTask | t.CPtr = (LlcTask | t.CPtr)(uint64(tasks) + sizet(pi2) * LlcTask.__sizeof__())
             if tsk_p is None:
                 continue
+            if tsk_p.MlirOptCmd is not None:
+                _phase2_write_cmd(tsk_p.MlirOptCmd)
+            if tsk_p.MlirTranslateCmd is not None:
+                _phase2_write_cmd(tsk_p.MlirTranslateCmd)
             if tsk_p.OptCmd is not None:
                 _phase2_write_cmd(tsk_p.OptCmd)
             if tsk_p.LlcCmd is not None:
diff --git a/App/lib/Projectrans/Config.vp b/App/lib/Projectrans/Config.vp
index 436b7fa..086509c 100644
--- a/App/lib/Projectrans/Config.vp
+++ b/App/lib/Projectrans/Config.vp
@@ -43,6 +43,17 @@ IncludesDirs: str = None          # 全部 includes 目录（空格分隔，多
 # includes 预编译缓存目录后缀（asan 模式用 .binary_asan 隔离 asan 插桩 obj，避免与非 asan obj 混链）
 _inc_bin_suffix: str = ".binary"
 
+# ============================================================
+# 后端（Emitter Backend）
+#
+# "llvm"（默认）：IR 发射走 includes/llvmlite（LLVM IR 文本），opt/llc 直接消费。
+# "mlir"        ：模块名 llvmlite 在解析层重定向到 includes/mlirlite（MLIR 文本），
+#                 并在 opt/llc 之前插入 mlir-opt（校验）→ mlir-translate（降级回 LLVM IR）。
+# 只认字符串 "mlir"：缺省 / 未知值一律按 LLVM（BackendIsMlir=0），保证默认路径逐字不变。
+# ============================================================
+BackendTarget: str = "llvm"
+BackendIsMlir: int = 0
+
 
 def Load_project_config(path: str) -> int:
     """加载工程配置文件（project.vpj）
@@ -145,6 +156,16 @@ def Load_project_config(path: str) -> int:
         sm: JsonValue | t.CPtr = options["strict_mode"]
         if sm is not None and sm.is_bool():
             StrictMode = 1 if sm.as_bool() else 0
+        # 后端：options.backend（新键）优先，回退 options.target（兼容旧键）。
+        # 只认 "mlir"；其余（含缺省/未知）按 LLVM。CLI --backend 由 main.vp
+        # 在本函数返回后覆盖（CLI 优先级最高）。
+        be_val: JsonValue | t.CPtr = options["backend"]
+        if be_val is not None and be_val.is_string():
+            set_backend(be_val.as_string())
+        else:
+            tgt_be: JsonValue | t.CPtr = options["target"]
+            if tgt_be is not None and tgt_be.is_string():
+                set_backend(tgt_be.as_string())
 
     # 读取 includes 数组（支持多目录：首元素存 IncludesDir，全部拼接存 IncludesDirs）
     includes_val: JsonValue | t.CPtr = root["includes"]
@@ -424,17 +445,19 @@ def resolve_paths(project_dir: str) -> int:
     SourceDir = _join_path(SourceDir, project_dir)
     BuildDir = _join_path(BuildDir, project_dir)
 
-    # TempDir = {BuildDir}/temp
+    # TempDir = {BuildDir}/temp（非 LLVM 后端追加隔离后缀，如 _mlir；LLVM 时后缀为空串，路径逐字不变）
     if BuildDir is not None:
         bd_len: sizet = string.strlen(BuildDir)
-        temp_buf: str = _mbuddy.alloc(bd_len + 8)
+        suf_dir: str = backend_dir_suffix()
+        suf_dir_len: sizet = string.strlen(suf_dir)
+        temp_buf: str = _mbuddy.alloc(bd_len + suf_dir_len + 8)
         if temp_buf is not None:
-            viperlib.snprintf(temp_buf, bd_len + 8, "%s/temp", BuildDir)
+            viperlib.snprintf(temp_buf, bd_len + suf_dir_len + 8, "%s/temp%s", BuildDir, suf_dir)
             TempDir = temp_buf
         # OutputDir = {BuildDir}/output
-        output_buf: str = _mbuddy.alloc(bd_len + 8)
+        output_buf: str = _mbuddy.alloc(bd_len + suf_dir_len + 8)
         if output_buf is not None:
-            viperlib.snprintf(output_buf, bd_len + 8, "%s/output", BuildDir)
+            viperlib.snprintf(output_buf, bd_len + suf_dir_len + 8, "%s/output%s", BuildDir, suf_dir)
             OutputDir = output_buf
 
     # includes 路径可能是 ../includes 形式，需要基于 project_dir 解析
@@ -638,18 +661,71 @@ def get_includes_binary_dir() -> str:
     includes 目录如 ../includes，默认返回 ../includes.binary；
     asan 模式（set_inc_bin_suffix(".binary_asan")）返回 ../includes.binary_asan，
     隔离 asan 插桩 obj，避免与非 asan obj 混链。
+    非 LLVM 后端再追加后端后缀（如 .binary_asan_mlir），隔离不同后端的 obj。
     """
     if IncludesDir is None:
         return None
     inc_len: sizet = string.strlen(IncludesDir)
     suf_len: sizet = string.strlen(_inc_bin_suffix)
-    buf: str = _mbuddy.alloc(inc_len + suf_len + 1)
+    be_suf: str = backend_dir_suffix()
+    be_suf_len: sizet = string.strlen(be_suf)
+    buf: str = _mbuddy.alloc(inc_len + suf_len + be_suf_len + 1)
     if buf is None:
         return None
-    viperlib.snprintf(buf, inc_len + suf_len + 1, "%s%s", IncludesDir, _inc_bin_suffix)
+    viperlib.snprintf(buf, inc_len + suf_len + be_suf_len + 1, "%s%s%s", IncludesDir, _inc_bin_suffix, be_suf)
     return buf
 
 
+# ============================================================
+# 后端开关（Emitter Backend）
+#
+# set_backend: 只接受 "llvm" / "mlir"（其余返回 1 且不改动），大小写敏感。
+# backend_dir_suffix: 非默认后端的目录隔离后缀；LLVM 后端返回空串（调用方拼出的
+#                    路径与改前逐字相同）。用于 TempDir/OutputDir/includes.binary。
+# is_mlir_backend: 0/1 便捷视图（BuildPipeline 降级管线的门）。
+# ============================================================
+def set_backend(name: str) -> int:
+    """设置后端；0=成功，1=非法（name 为 None 或非 llvm/mlir）"""
+    global BackendTarget, BackendIsMlir
+    if name is None:
+        return 1
+    if string.strcmp(name, "llvm") == 0:
+        BackendTarget = name
+        BackendIsMlir = 0
+        return 0
+    if string.strcmp(name, "mlir") == 0:
+        BackendTarget = name
+        BackendIsMlir = 1
+        return 0
+    return 1
+
+
+def is_mlir_backend() -> int:
+    """是否 MLIR 后端（1=mlir / 0=llvm）"""
+    return BackendIsMlir
+
+
+def backend_dir_suffix() -> str:
+    """非默认后端的目录隔离后缀（LLVM 后端返回空串 ⇒ 路径逐字不变）"""
+    if BackendIsMlir != 0:
+        return "_mlir"
+    return ""
+
+
+def alias_module_name(name: str) -> str:
+    """MLIR 后端下把模块名 "llvmlite" 重定向到 "mlirlite"（其余原样返回）。
+
+    这是"TransPyV 调用点零改动"的唯一开关：所有 **名称→模块/文件/SHA1** 的解析
+    都应经此函数（模块文件解析 IncludesScanner.ResolveModuleToPath、依赖名→SHA1
+    StubMergerIR._FindSha1ByModName 等）。LLVM 后端恒等返回，默认路径逐字不变。
+    """
+    if name is None:
+        return None
+    if BackendIsMlir != 0 and string.strcmp(name, "llvmlite") == 0:
+        return "mlirlite"
+    return name
+
+
 def asan_runtime_declared() -> int:
     """project.vpj 是否已声明 ASan 运行库（1 = 声明过）
 
diff --git a/App/lib/Stub/StubMerger/StubMergerIR.vp b/App/lib/Stub/StubMerger/StubMergerIR.vp
index 8c8ead0..68df257 100644
--- a/App/lib/Stub/StubMerger/StubMergerIR.vp
+++ b/App/lib/Stub/StubMerger/StubMergerIR.vp
@@ -335,6 +335,11 @@ def _FindSha1ByModName(sha1_arr: str, mod_arr: str,
         return None
     if count <= 0:
         return None
+    # MLIR 后端：依赖名 "llvmlite" 重定向到 "mlirlite"
+    #（与 IncludesScanner.ResolveModuleToPath 同口径；LLVM 后端恒等）
+    mod_name = Config.alias_module_name(mod_name)
+    if mod_name is None:
+        return None
     # 第一遍：精确匹配
     for i in range(count):
         idx: sizet = sizet(i) * 64
diff --git a/App/lib/core/IncludesScanner.vp b/App/lib/core/IncludesScanner.vp
index f73102b..9774a28 100644
--- a/App/lib/core/IncludesScanner.vp
+++ b/App/lib/core/IncludesScanner.vp
@@ -10,6 +10,7 @@ import hashlib
 import viperlib
 import lib.Projectrans.Utils as Utils
 import lib.core.VLogger as VLogger
+import lib.Projectrans.Config as Config
 
 
 # ============================================================
@@ -452,6 +453,12 @@ def ResolveModuleToPath(includes_dirs: str, mod_name: str,
                         out_inc_dir: t.CPtr) -> int:
     if includes_dirs is None or mod_name is None:
         return 1
+    # MLIR 后端：模块名 "llvmlite" 重定向到 "mlirlite"（TransPyV 调用点零改动）。
+    # 重定向后的名字用于本次解析的路径段/相对路径，调用方拿到的 rel_path
+    # 即 "mlirlite/__init__.vp" ⇒ 下游模块身份/SHA1 全部随之一致。
+    mod_name = Config.alias_module_name(mod_name)
+    if mod_name is None:
+        return 1
     mn_len: sizet = string.strlen(mod_name)
     if mn_len == 0:
         return 1
diff --git a/App/main.vp b/App/main.vp
index 8c7725c..19bae7a 100644
--- a/App/main.vp
+++ b/App/main.vp
@@ -162,6 +162,7 @@ def main() -> int:
     parser.add_argument("--repl",             None, argparse.BOOL, 0, None, False, argparse.STORE_TRUE, "Start the interactive REPL (M2 session variables + M3 cross-fragment functions: fragment -> DLL -> call)")
     parser.add_argument("--build-dir",        None, argparse.STRING, 0, None, False, argparse.STORE, "Override project.vpj build_dir (default ./.tpv_build; relative paths resolve against the project dir)")
     parser.add_argument("--no-llvmpeephole",  None, argparse.BOOL, 0, None, False, argparse.STORE_TRUE, "Disable all local llvmlite peephole passes (T2 store/load forward & ret-zero, T3 no-op bitcast) in FunctionPrint serialization")
+    parser.add_argument("--backend",          None, argparse.STRING, 0, None, False, argparse.STORE, "Emitter backend: llvm (default) | mlir. mlir redirects module 'llvmlite' to includes/mlirlite and inserts mlir-opt + mlir-translate before opt/llc")
     parser.add_argument("--version",          "-v", argparse.BOOL, 0, None, False, argparse.STORE_TRUE, "Show version and exit")
     parser.add_argument("--help",             "-h", argparse.BOOL, 0, None, False, argparse.STORE_TRUE, "Show help and exit")
 
@@ -369,6 +370,17 @@ Target: %s
                 proj_path = "../project.vpj"
                 if Config.Load_project_config(proj_path) == 0:
                     proj_loaded = 1
+    # === --backend: CLI 覆盖 project.vpj 的 options.backend（CLI 优先级最高）===
+    # 位置：工程配置加载之后（options.backend 已读入）、resolve_paths 之前
+    #（TempDir/OutputDir 的后端隔离后缀由此定型）；非法值 fail-fast。
+    gb_backend: str = args.get_str("backend")
+    if gb_backend is not None:
+        if Config.set_backend(gb_backend) != 0:
+            log.error(f"非法的 --backend 值: '{gb_backend}'（只支持 llvm / mlir）", "backend")
+            argparse.release(args)
+            return 1
+    log.info(f"后端: {Config.BackendTarget}", "backend")
+
     if proj_loaded == 1:
         # 提取 project.vpj 所在目录，将相对路径解析为基于该目录的路径
         proj_len: sizet = string.strlen(proj_path)