chore: import upstream snapshot with attribution

python/tvm/base.py

@@ -0,0 +1,61 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# coding: utf-8
+# pylint: disable=invalid-name, import-outside-toplevel
+"""Base library for TVM."""
+
+import os
+
+from tvm_ffi.libinfo import load_lib_ctypes
+
+from . import libinfo
+
+# ----------------------------
+# library loading
+# ----------------------------
+
+# Whether only the runtime library is loaded (runtime-only wheel, or
+# ``TVM_USE_RUNTIME_LIB=1``). Set during library loading below.
+_RUNTIME_ONLY = os.environ.get("TVM_USE_RUNTIME_LIB") == "1"
+
+# Handles of the core libraries actually loaded, keyed by basename
+# (e.g. ``{"tvm_runtime": <CDLL>, "tvm_compiler": <CDLL>}``). Downstream /
+# autoloaded extensions can inspect this to skip duplicate libraries
+# (``"tvm_runtime" in _LOADED_LIBS``) and obtain the loaded handle.
+_LOADED_LIBS = {}
+
+
+# runtime is loaded RTLD_GLOBAL to expose its symbols to subsequent loads;
+# compiler is loaded RTLD_LOCAL.
+_LOADED_LIBS["tvm_runtime"] = load_lib_ctypes(
+    "tvm", "tvm_runtime", "RTLD_GLOBAL", extra_lib_paths=libinfo.package_lib_paths()
+)
+
+if not _RUNTIME_ONLY:
+    try:
+        _LOADED_LIBS["tvm_compiler"] = load_lib_ctypes(
+            "tvm", "tvm_compiler", "RTLD_LOCAL", extra_lib_paths=libinfo.package_lib_paths()
+        )
+    except (RuntimeError, OSError):
+        # Compiler lib not present, or present but unloadable (missing LLVM
+        # deps / linker issues) — fall back to runtime-only mode.
+        _RUNTIME_ONLY = True
+
+if _RUNTIME_ONLY:
+    from tvm_ffi import registry as _tvm_ffi_registry
+
+    _tvm_ffi_registry._SKIP_UNKNOWN_OBJECTS = True