[MODULE/DSO] Support pack everything into one shared library. (#133)

* [MODULE/DSO] Support pack everything into one shared library.

* fix osx load

dmlc-core @ a6c57012

-Subproject commit 2b75a0ce6f191ad0fcb5319039b41e990968542a
+Subproject commit a6c5701219e635fea808d264aefc5b03c3aec314

include/tvm/codegen.h

@@ -31,6 +31,16 @@ using runtime::TVMRetValue;
  */
 runtime::Module Build(const Array<LoweredFunc>& funcs,
                       const std::string& target);
+/*!
+ * \brief Pack imported device library to a C file.
+ *  Compile the C file and link with the host library
+ *  will allow the DSO loader to automatically discover and import
+ *  the dependency from the shared library.
+ *
+ * \param m The host module with the imports.
+ * \return cstr The C string representation of the file.
+ */
+std::string PackImportsToC(const runtime::Module& m);
 }  // namespace codegen
 }  // namespace tvm
 

include/tvm/runtime/module.h

@@ -8,6 +8,7 @@
 #ifndef TVM_RUNTIME_MODULE_H_
 #define TVM_RUNTIME_MODULE_H_
 
+#include <dmlc/io.h>
 #include <memory>
 #include <vector>
 #include <string>
@@ -58,6 +59,8 @@ class Module {
                              const std::string& format);
   /*! \return internal container */
   inline ModuleNode* operator->();
+  /*! \return internal container */
+  inline const ModuleNode* operator->() const;
 
  private:
   std::shared_ptr<ModuleNode> node_;
@@ -112,13 +115,20 @@ class ModuleNode {
   virtual void SaveToFile(const std::string& file_name,
                           const std::string& format) = 0;
   /*!
+   * \brief Save the module to binary stream.
+   * \param stream The binary stream to save to.
+   * \note It is recommended to implement this for device modules,
+   *   but not necessarily host modules.
+   *   We can use this to do AOT loading of bundled device functions.
+   */
+  virtual void SaveToBinary(dmlc::Stream* stream) = 0;
+  /*!
    * \brief Get the source code of module, when available.
    * \param format Format of the source code, can be empty by default.
    * \return Possible source code when available.
    */
   virtual std::string GetSource(
       const std::string& format = "") = 0;
-
   /*!
    * \brief Get a function from current environment
    *  The environment includes all the imports as well as Global functions.
@@ -132,10 +142,12 @@ class ModuleNode {
     return imports_;
   }
 
- private:
+ protected:
   friend class Module;
   /*! \brief The modules this module depend on */
   std::vector<Module> imports_;
+
+ private:
   /*! \brief Cache used by GetImport */
   std::unordered_map<std::string,
                      std::unique_ptr<PackedFunc> > import_cache_;
@@ -145,6 +157,10 @@ class ModuleNode {
 namespace symbol {
 /*! \brief Global variable to store module context. */
 constexpr const char* tvm_module_ctx = "__tvm_module_ctx";
+/*! \brief Global variable to store device module blob */
+constexpr const char* tvm_dev_mblob = "__tvm_dev_mblob";
+/*! \brief Number of bytes of device module blob. */
+constexpr const char* tvm_dev_mblob_nbytes = "__tvm_dev_mblob_nbytes";
 /*! \brief global function to set device */
 constexpr const char* tvm_set_device = "__tvm_set_device";
 /*! \brief Auxiliary counter to global barrier. */
@@ -160,6 +176,10 @@ inline ModuleNode* Module::operator->() {
   return node_.get();
 }
 
+inline const ModuleNode* Module::operator->() const {
+  return node_.get();
+}
+
 }  // namespace runtime
 }  // namespace tvm
 

python/tvm/module.py

@@ -2,7 +2,7 @@
 from __future__ import absolute_import as _abs
 from ._ffi.function import ModuleBase, _set_class_module
 from ._ffi.function import _init_api
-
+from .contrib import cc_compiler as _cc, util as _util
 
 class Module(ModuleBase):
     """Module container of all TVM generated functions"""
@@ -44,15 +44,46 @@ class Module(ModuleBase):
     def save(self, file_name, fmt=""):
         """Save the module to file.
 
+        This do not save the dependent device modules.
+        See also export_shared
+
         Parameters
         ----------
         file_name : str
             The name of the file.
         fmt : str
             The format of the file.
+
+        See Also
+        --------
+        Module.export_library : export the module to shared library.
         """
         _SaveToFile(self, file_name, fmt)
 
+    def export_library(self, file_name):
+        """Export the module and its imported device code one library.
+
+        This function only works on host llvm modules.
+        It will pack all the imported modules
+
+        Parameters
+        ----------
+        file_name : str
+            The name of the shared library.
+        """
+        if self.type_key != "llvm":
+            raise ValueError("Only llvm support export shared")
+        temp = _util.tempdir()
+        path_obj = temp.relpath("lib.o")
+        self.save(path_obj)
+        files = [path_obj]
+        if self.imported_modules:
+            path_cc = temp.relpath("devc.cc")
+            with open(path_cc, "w") as f:
+                f.write(_PackImportsToC(self))
+            files.append(path_cc)
+        _cc.create_shared(file_name, files)
+
 
 def load(path, fmt=""):
     """Load module from file

src/api/api_codegen.cc

@@ -20,5 +20,10 @@ TVM_REGISTER_API("codegen._Build")
       *ret = Build(args[0], args[1]);
     }
   });
+
+TVM_REGISTER_API("module._PackImportsToC")
+.set_body([](TVMArgs args, TVMRetValue *ret) {
+    *ret = PackImportsToC(args[0]);
+  });
 }  // namespace codegen
 }  // namespace tvm

src/codegen/codegen.cc

@@ -7,6 +7,9 @@
 #include <tvm/ir_pass.h>
 #include <tvm/runtime/registry.h>
 #include <tvm/runtime/module.h>
+#include <dmlc/memory_io.h>
+#include <sstream>
+#include <iostream>
 
 namespace tvm {
 namespace codegen {
@@ -32,5 +35,50 @@ runtime::Module Build(const Array<LoweredFunc>& funcs,
   return m;
 }
 
+std::string PackImportsToC(const runtime::Module& mod) {
+  std::string bin;
+  dmlc::MemoryStringStream ms(&bin);
+  dmlc::Stream* stream = &ms;
+  uint64_t sz = static_cast<uint64_t>(mod->imports().size());
+  stream->Write(sz);
+  for (runtime::Module im : mod->imports()) {
+    CHECK_EQ(im->imports().size(), 0U)
+        << "Only support simply one-level hierachy";
+    std::string tkey = im->type_key();
+    std::string bin;
+    stream->Write(tkey);
+    im->SaveToBinary(stream);
+  }
+  // translate to C program
+  std::ostringstream os;
+  os << "#ifdef __cplusplus\n"
+     << "extern \"C\" {\n"
+     << "#endif\n";
+  os << "extern const char " << runtime::symbol::tvm_dev_mblob << "[];\n";
+  os << "extern const unsigned long " << runtime::symbol::tvm_dev_mblob_nbytes << ";\n";
+  os << "const char " << runtime::symbol::tvm_dev_mblob
+     << "[" << bin.length() << "] = {\n  ";
+  os << std::hex;
+  size_t nunit = 80 / 4;
+  for (size_t i = 0; i < bin.length(); ++i) {
+    // sperators
+    if (i != 0) {
+      if (i % nunit == 0) {
+        os << ",\n  ";
+      } else {
+        os << ",";
+      }
+    }
+    int c = bin[i];
+    os << "0x" << (c & 0xff);
+  }
+  os << "\n};\n"
+     << "const unsigned long " << runtime::symbol::tvm_dev_mblob_nbytes
+     << " = " << std::dec << bin.length() << "UL;\n"
+     << "#ifdef __cplusplus\n"
+     << "}\n"
+     << "#endif\n";
+  return os.str();
+}
 }  // namespace codegen
 }  // namespace tvm

src/codegen/llvm/llvm_module.cc

@@ -19,7 +19,7 @@ using runtime::TVMArgs;
 using runtime::TVMRetValue;
 using runtime::PackedFunc;
 
-class LLVMModuleNode : public runtime::ModuleNode {
+class LLVMModuleNode final : public runtime::ModuleNode {
  public:
   ~LLVMModuleNode() {
     module_.reset();
@@ -84,6 +84,10 @@ class LLVMModuleNode : public runtime::ModuleNode {
     dest.close();
   }
 
+  void SaveToBinary(dmlc::Stream* stream) final {
+    LOG(FATAL) << "LLVMModule: SaveToBinary not supported";
+  }
+
   std::string GetSource(const std::string& format) final {
     std::string type_str;
     llvm::raw_string_ostream rso(type_str);

src/codegen/source_module.cc

@@ -13,7 +13,7 @@ using runtime::TVMArgs;
 using runtime::TVMRetValue;
 using runtime::PackedFunc;
 // Simulator function
-class SourceModuleNode : public runtime::ModuleNode {
+class SourceModuleNode final : public runtime::ModuleNode {
  public:
   SourceModuleNode(std::string code,
                    std::string fmt)
@@ -30,10 +30,16 @@ class SourceModuleNode : public runtime::ModuleNode {
                << " build TVM with \'" << fmt_ << "\' runtime support";
     return PackedFunc();
   }
+
   void SaveToFile(const std::string& file_name,
                   const std::string& format) final {
-    LOG(FATAL) << "not implemented";
+    LOG(FATAL) << "SourceModule: SaveToFile not supported";
+  }
+
+  void SaveToBinary(dmlc::Stream* stream) final {
+    LOG(FATAL) << "SourceModule: SaveToBinary not supported";
   }
+
   std::string GetSource(const std::string& format) final {
     return code_;
   }

src/codegen/stack_vm/stack_vm_module.cc

@@ -35,7 +35,11 @@ class StackVMModuleNode : public runtime::ModuleNode {
 
   void SaveToFile(const std::string& file_name,
                   const std::string& format) final {
-    LOG(FATAL) << "StackVM do not support SaveToFile";
+    LOG(FATAL) << "StackVMModule: SaveToFile not supported";
+  }
+
+  void SaveToBinary(dmlc::Stream* stream) final {
+    LOG(FATAL) << "StackVMModule: SaveToBinary not supported";
   }
 
   std::string GetSource(const std::string& format) final {

src/codegen/verilog/verilog_module.cc

@@ -59,7 +59,11 @@ class VerilogModuleNode : public runtime::ModuleNode {
 
   void SaveToFile(const std::string& file_name,
                   const std::string& format) final {
-    LOG(FATAL) << "not implemented";
+    LOG(FATAL) << "VerilogModule: SaveToFile not supported";
+  }
+
+  void SaveToBinary(dmlc::Stream* stream) final {
+    LOG(FATAL) << "VerilogModule: SaveToBinary not supported";
   }
 
   std::string GetSource(const std::string& format) final {

src/runtime/cuda/cuda_module.cc

@@ -69,6 +69,12 @@ class CUDAModuleNode : public runtime::ModuleNode {
     SaveBinaryToFile(file_name, data_);
   }
 
+  void SaveToBinary(dmlc::Stream* stream) final {
+    stream->Write(fmt_);
+    stream->Write(fmap_);
+    stream->Write(data_);
+  }
+
   std::string GetSource(const std::string& format) final {
     if (format == fmt_) return data_;
     if (cuda_source_.length() != 0) {
@@ -242,7 +248,7 @@ Module CUDAModuleCreate(
 }
 
 // Load module from module.
-Module CUDAModuleLoad(const std::string& file_name,
+Module CUDAModuleLoadFile(const std::string& file_name,
                           const std::string& format) {
   std::string data;
   std::unordered_map<std::string, FunctionInfo> fmap;
@@ -253,14 +259,30 @@ Module CUDAModuleLoad(const std::string& file_name,
   return CUDAModuleCreate(data, fmt, fmap, std::string());
 }
 
+Module CUDAModuleLoadBinary(void* strm) {
+  dmlc::Stream* stream = static_cast<dmlc::Stream*>(strm);
+  std::string data;
+  std::unordered_map<std::string, FunctionInfo> fmap;
+  std::string fmt;
+  stream->Read(&fmt);
+  stream->Read(&fmap);
+  stream->Read(&data);
+  return CUDAModuleCreate(data, fmt, fmap, std::string());
+}
+
 TVM_REGISTER_GLOBAL("module.loadfile_cubin")
 .set_body([](TVMArgs args, TVMRetValue* rv) {
-    *rv = CUDAModuleLoad(args[0], args[1]);
+    *rv = CUDAModuleLoadFile(args[0], args[1]);
   });
 
 TVM_REGISTER_GLOBAL("module.loadfile_ptx")
 .set_body([](TVMArgs args, TVMRetValue* rv) {
-    *rv = CUDAModuleLoad(args[0], args[1]);
+    *rv = CUDAModuleLoadFile(args[0], args[1]);
+  });
+
+TVM_REGISTER_GLOBAL("module.loadbinary_cuda")
+.set_body([](TVMArgs args, TVMRetValue* rv) {
+    *rv = CUDAModuleLoadBinary(args[0]);
   });
 }  // namespace runtime
 }  // namespace tvm

src/runtime/dso_module.cc

@@ -3,6 +3,7 @@
  * \file dso_module.cc
  * \brief Module to load from dynamic shared library.
  */
+#include <dmlc/memory_io.h>
 #include <tvm/runtime/module.h>
 #include <tvm/runtime/registry.h>
 #include <tvm/runtime/packed_func.h>
@@ -19,7 +20,7 @@ namespace runtime {
 
 // Module to load from dynamic shared libary.
 // This is the default module TVM used for hostside AOT
-class DSOModuleNode : public ModuleNode {
+class DSOModuleNode final : public ModuleNode {
  public:
   ~DSOModuleNode() {
     if (lib_handle_) Unload();
@@ -49,7 +50,11 @@ class DSOModuleNode : public ModuleNode {
 
   void SaveToFile(const std::string& file_name,
                   const std::string& format) final {
-    LOG(FATAL) << "Cannot save dso to another file";
+    LOG(FATAL) << "DSOModule: SaveToFile not supported";
+  }
+
+  void SaveToBinary(dmlc::Stream* stream) final {
+    LOG(FATAL) << "DSOModule: SaveToBinary not supported";
   }
 
   std::string GetSource(const std::string& format) final {
@@ -66,6 +71,33 @@ class DSOModuleNode : public ModuleNode {
     if (ctx_addr != nullptr) {
       *ctx_addr = this;
     }
+    // Load the imported modules
+    const char* dev_mblob =
+        reinterpret_cast<const char*>(
+            GetGlobalVPtr(runtime::symbol::tvm_dev_mblob));
+    const unsigned long* dev_mblob_nbytes =   // NOLINT(*)
+        reinterpret_cast<const unsigned long*>(  // NOLINT(*)
+            GetGlobalVPtr(runtime::symbol::tvm_dev_mblob_nbytes));
+
+    if (dev_mblob != nullptr) {
+      CHECK(dev_mblob_nbytes != nullptr);
+      dmlc::MemoryFixedSizeStream fs(
+          (void*)dev_mblob, dev_mblob_nbytes[0]);  // NOLINT(*)
+      dmlc::Stream* stream = &fs;
+      uint64_t size;
+      CHECK(stream->Read(&size));
+      for (uint64_t i = 0; i < size; ++i) {
+        std::string tkey;
+        CHECK(stream->Read(&tkey));
+        std::string fkey = "module.loadbinary_" + tkey;
+        const PackedFunc* f = Registry::Get(fkey);
+        CHECK(f != nullptr)
+            << "Loader of " << tkey << "("
+            << fkey << ") is not presented.";
+        Module m = (*f)(static_cast<void*>(stream));
+        this->imports_.push_back(m);
+      }
+    }
   }
 
  private:

src/runtime/file_util.cc

@@ -36,6 +36,19 @@ void FunctionInfo::Load(dmlc::JSONReader* reader) {
   }
 }
 
+void FunctionInfo::Save(dmlc::Stream* writer) const {
+  writer->Write(name);
+  writer->Write(arg_types);
+  writer->Write(thread_axis_tags);
+}
+
+bool FunctionInfo::Load(dmlc::Stream* reader) {
+  if (!reader->Read(&name)) return false;
+  if (!reader->Read(&arg_types)) return false;
+  if (!reader->Read(&thread_axis_tags)) return false;
+  return true;
+}
+
 std::string GetFileFormat(const std::string& file_name,
                           const std::string& format) {
   std::string fmt = format;

src/runtime/meta_data.h

@@ -29,7 +29,13 @@ struct FunctionInfo {
 
   void Save(dmlc::JSONWriter *writer) const;
   void Load(dmlc::JSONReader *reader);
+  void Save(dmlc::Stream *writer) const;
+  bool Load(dmlc::Stream *reader);
 };
 }  // namespace runtime
 }  // namespace tvm
+
+namespace dmlc {
+DMLC_DECLARE_TRAITS(has_saveload, ::tvm::runtime::FunctionInfo, true);
+}  // namespace dmlc
 #endif  // TVM_RUNTIME_META_DATA_H_

src/runtime/metal/metal_module.mm

@@ -6,6 +6,7 @@
 
 #if TVM_METAL_RUNTIME
 
+#include <dmlc/memory_io.h>
 #include <tvm/runtime/registry.h>
 #include <tvm/runtime/module.h>
 #include <array>
@@ -54,6 +55,11 @@ class MetalModuleNode final :public runtime::ModuleNode {
     SaveBinaryToFile(file_name, data_);
   }
 
+  void SaveToBinary(dmlc::Stream* stream) final {
+    stream->Write(fmt_);
+    stream->Write(fmap_);
+    stream->Write(data_);
+  }
   std::string GetSource(const std::string& format) final {
     if (format == fmt_) return data_;
     if (source_.length() != 0) {
@@ -261,7 +267,7 @@ Module MetalModuleCreate(
 }
 
 // Load module from module.
-Module MetalModuleLoad(const std::string& file_name,
+Module MetalModuleLoadFile(const std::string& file_name,
                            const std::string& format) {
   std::string data;
   std::unordered_map<std::string, FunctionInfo> fmap;
@@ -272,9 +278,25 @@ Module MetalModuleLoad(const std::string& file_name,
   return MetalModuleCreate(data, fmt, fmap, "");
 }
 
+Module MetalModuleLoadBinary(void* strm) {
+  dmlc::Stream* stream = static_cast<dmlc::Stream*>(strm);
+  std::string data;
+  std::unordered_map<std::string, FunctionInfo> fmap;
+  std::string fmt;
+  stream->Read(&fmt);
+  stream->Read(&fmap);
+  stream->Read(&data);
+  return MetalModuleCreate(data, fmt, fmap, "");
+}
+
 TVM_REGISTER_GLOBAL("module.loadfile_metal")
 .set_body([](TVMArgs args, TVMRetValue* rv) {
-    *rv = MetalModuleLoad(args[0], args[1]);
+    *rv = MetalModuleLoadFile(args[0], args[1]);
+    });
+
+TVM_REGISTER_GLOBAL("module.loadbinary_metal")
+.set_body([](TVMArgs args, TVMRetValue* rv) {
+    *rv = MetalModuleLoadBinary(args[0]);
     });
 }  // namespace runtime
 }  // namespace tvm

src/runtime/opencl/opencl_module.cc

@@ -7,6 +7,7 @@
 
 #if TVM_OPENCL_RUNTIME
 
+#include <dmlc/memory_io.h>
 #include <tvm/runtime/registry.h>
 #include <vector>
 #include <string>
@@ -78,6 +79,12 @@ class OpenCLModuleNode : public ModuleNode {
     SaveBinaryToFile(file_name, data_);
   }
 
+  void SaveToBinary(dmlc::Stream* stream) final {
+    stream->Write(fmt_);
+    stream->Write(fmap_);
+    stream->Write(data_);
+  }
+
   std::string GetSource(const std::string& format) final {
     if (format == fmt_) return data_;
     if (fmt_ == "cl") {
@@ -272,7 +279,7 @@ Module OpenCLModuleCreate(
 }
 
 // Load module from module.
-Module OpenCLModuleLoad(const std::string& file_name,
+Module OpenCLModuleLoadFile(const std::string& file_name,
                             const std::string& format) {
   std::string data;
   std::unordered_map<std::string, FunctionInfo> fmap;
@@ -283,14 +290,30 @@ Module OpenCLModuleLoad(const std::string& file_name,
   return OpenCLModuleCreate(data, fmt, fmap);
 }
 
+Module OpenCLModuleLoadBinary(void* strm) {
+  dmlc::Stream* stream = static_cast<dmlc::Stream*>(strm);
+  std::string data;
+  std::unordered_map<std::string, FunctionInfo> fmap;
+  std::string fmt;
+  stream->Read(&fmt);
+  stream->Read(&fmap);
+  stream->Read(&data);
+  return OpenCLModuleCreate(data, fmt, fmap);
+}
+
 TVM_REGISTER_GLOBAL("module.loadfile_cl")
 .set_body([](TVMArgs args, TVMRetValue* rv) {
-    *rv = OpenCLModuleLoad(args[0], args[1]);
+    *rv = OpenCLModuleLoadFile(args[0], args[1]);
   });
 
 TVM_REGISTER_GLOBAL("module.loadfile_clbin")
 .set_body([](TVMArgs args, TVMRetValue* rv) {
-    *rv = OpenCLModuleLoad(args[0], args[1]);
+    *rv = OpenCLModuleLoadFile(args[0], args[1]);
+  });
+
+TVM_REGISTER_GLOBAL("module.loadbinary_opencl")
+.set_body([](TVMArgs args, TVMRetValue* rv) {
+    *rv = OpenCLModuleLoadBinary(args[0]);
   });
 }  // namespace runtime
 }  // namespace tvm

tests/python/integration/test_ewise.py

@@ -95,7 +95,6 @@ def test_add():
                          device,
                          name="myadd")
         ctx = tvm.context(device, 0)
-        print(fadd.imported_modules[0].get_source())
         # launch the kernel.
         n = 1024
         a = tvm.nd.array(np.random.uniform(size=n).astype(A.dtype), ctx)

tests/python/unittest/test_module_load.py

@@ -68,5 +68,39 @@ def test_dso_module_load():
         "python %s %s %s" % (path_runtime_py, path_dso, dtype),
         shell=True)
 
+
+def test_device_module_dump():
+    # graph
+    n = tvm.convert(1024)
+    A = tvm.placeholder((n,), name='A')
+    B = tvm.compute(A.shape, lambda *i: A(*i) + 1.0, name='B')
+    s = tvm.create_schedule(B.op)
+    # create iter var and assign them tags.
+    num_thread = 8
+    bx, tx = s[B].split(B.op.axis[0], factor=num_thread)
+    s[B].bind(bx, tvm.thread_axis("blockIdx.x"))
+    s[B].bind(tx, tvm.thread_axis("threadIdx.x"))
+
+    def check_device(device):
+        ctx = tvm.context(device, 0)
+        if not ctx.exist:
+            print("Skip because %s is not enabled" % device)
+            return
+        temp = util.tempdir()
+        f = tvm.build(s, [A, B], device, name="myadd")
+        path_dso = temp.relpath("dev_lib.so")
+        f.export_library(path_dso)
+
+        f1 = tvm.module.load(path_dso)
+        a = tvm.nd.array(np.random.uniform(size=1024).astype(A.dtype), ctx)
+        b = tvm.nd.array(np.zeros(1024, dtype=A.dtype), ctx)
+        f1(a, b)
+        np.testing.assert_equal(b.asnumpy(), a.asnumpy() + 1)
+
+    check_device("cuda")
+    check_device("opencl")
+    check_device("metal")
+
 if __name__ == "__main__":
+    test_device_module_dump()
     test_dso_module_load()

tutorials/python/get_started.py

@@ -190,8 +190,7 @@ print(temp.listdir())
 #   The CPU(host) module is directly saved as a shared library(so).
 #   There can be multiple customed format on the device code.
 #   In our example, device code is stored in ptx, as well as a meta
-#   data json file. In the future we can consider pack every binary
-#   into one shared library.
+#   data json file. They can be loaded and linked seperatedly via import.
 #
 
 ######################################################################
@@ -208,6 +207,20 @@ fadd1(a, b, c)
 np.testing.assert_allclose(c.asnumpy(), a.asnumpy() + b.asnumpy())
 
 ######################################################################
+# Pack Everything into One Library
+# --------------------------------
+# In the above example, we store the device and host code seperatedly.
+# TVM also support export everything as one shared library.
+# Under the hood, we pack the device modules into binary blobs and link
+# them together with the host code.
+# Currently we support packing of Metal, OpenCL and CUDA modules.
+#
+fadd_cuda.export_library(temp.relpath("myadd_pack.so"))
+fadd2 = tvm.module.load(temp.relpath("myadd_pack.so"))
+fadd2(a, b, c)
+np.testing.assert_allclose(c.asnumpy(), a.asnumpy() + b.asnumpy())
+
+######################################################################
 # .. note:: Runtime API and Thread-Safety
 #
 #   The compiled modules of TVM do not depend on the TVM compiler.