chore: import upstream snapshot with attribution

python/tvm/support/emcc.py

@@ -0,0 +1,145 @@
+# 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.
+"""Util to invoke emscripten compilers in the system."""
+
+# pylint: disable=invalid-name
+import os
+import subprocess
+from pathlib import Path
+
+from tvm import libinfo
+
+
+def find_wasm_lib(name, optional=False):
+    """Find a wasm/web asset (e.g. a ``.bc`` or ``.js`` file) under ``web/dist``.
+
+    Specializes the asset search to the wasm build outputs that live under
+    ``web/dist/wasm`` and ``web/dist``, anchored on ``TVM_HOME`` (when set) or
+    the TVM source root otherwise.
+
+    Parameters
+    ----------
+    name : str
+        The asset file name to look for.
+
+    optional : bool
+        When True, return None instead of raising if the asset is not found.
+
+    Returns
+    -------
+    found : list(str) or None
+        List of matching paths, or None when ``optional`` and nothing is found.
+    """
+    # use extra TVM_HOME environment for finding libraries.
+    if os.environ.get("TVM_HOME", None):
+        tvm_source_home_dir = os.environ["TVM_HOME"]
+    else:
+        tvm_source_home_dir = os.fspath(libinfo._dev_top_directory())
+
+    dll_path = [
+        os.path.join(tvm_source_home_dir, "web", "dist", "wasm"),
+        os.path.join(tvm_source_home_dir, "web", "dist"),
+    ]
+    found = [os.path.join(p, name) for p in dll_path if os.path.isfile(os.path.join(p, name))]
+    if not found:
+        if optional:
+            return None
+        raise RuntimeError(f"Cannot find {name}; searched {dll_path}")
+    return found
+
+
+def create_tvmjs_wasm(output, objects, options=None, cc="emcc", libs=None):
+    """Create wasm that is supposed to run with the tvmjs.
+
+    Parameters
+    ----------
+    output : str
+        The target shared library.
+
+    objects : list
+        List of object files.
+
+    options : str
+        The additional options.
+
+    cc : str, optional
+        The compile string.
+
+    libs : list
+        List of user-defined library files (e.g. .bc files) to add into the wasm.
+    """
+    cmd = [cc]
+    cmd += ["-O3"]
+    cmd += ["-std=c++17"]
+    cmd += ["--no-entry"]
+    # NOTE: asynctify conflicts with wasm-exception
+    # so we temp disable exception handling for now
+    #
+    # We also expect user to explicitly pass in
+    # -s ASYNCIFY=1 as it can increase wasm size by 2xq
+    #
+    # cmd += ["-s", "ASYNCIFY=1"]
+    # cmd += ["-fwasm-exceptions"]
+    cmd += ["-s", "WASM_BIGINT=1"]
+    cmd += ["-s", "ERROR_ON_UNDEFINED_SYMBOLS=0"]
+    cmd += ["-s", "STANDALONE_WASM=1"]
+    cmd += ["-s", "ALLOW_MEMORY_GROWTH=1"]
+    cmd += ["-s", "TOTAL_MEMORY=160MB"]
+
+    objects = [objects] if isinstance(objects, str) else objects
+
+    with_runtime = False
+    for obj in objects:
+        if obj.find("wasm_runtime.bc") != -1:
+            with_runtime = True
+
+    all_libs = []
+    if not with_runtime:
+        all_libs += [find_wasm_lib("wasm_runtime.bc")[0]]
+
+    all_libs += [find_wasm_lib("tvmjs_support.bc")[0]]
+    all_libs += [find_wasm_lib("webgpu_runtime.bc")[0]]
+
+    if libs:
+        if not isinstance(libs, list):
+            raise ValueError("Expect `libs` to be a list of paths in string.")
+        for lib in libs:
+            if not Path(lib).exists():
+                raise RuntimeError(
+                    "Cannot find file from libs:" + lib + "\n Try pass in an absolute path."
+                )
+        all_libs += libs
+
+    cmd += ["-o", output]
+
+    # let libraries go before normal object
+    cmd += all_libs + objects
+
+    if options:
+        cmd += options
+
+    is_windows = os.name == "nt"
+    proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, shell=is_windows)
+    (out, _) = proc.communicate()
+
+    if proc.returncode != 0:
+        msg = "Compilation error:\n"
+        msg += out.decode("utf-8", errors="replace")
+        raise RuntimeError(msg)
+
+
+create_tvmjs_wasm.object_format = "bc"