chore: import upstream snapshot with attribution

python/tvm/arith/pattern.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.
+"""Detect common patterns."""
+
+from . import _ffi_api
+
+
+def detect_linear_equation(expr, var_list):
+    """Match `expr = sum_{i=0}^{n-1} var[i] * coeff[i] + coeff[n]`
+
+    Where coeff[i] and base are invariant of var[j] for all i and j.
+
+    Parameters
+    ----------
+    expr : Expr
+        The expression to be matched.
+
+    var_list : List[tvm.tirx.Var]
+        A list of variables.
+
+    Returns
+    -------
+    coeff : List[Expr]
+        A list of co-efficients if the match is successful.
+        An empty list if the match failed.
+    """
+    return _ffi_api.DetectLinearEquation(expr, var_list)
+
+
+def detect_clip_bound(expr, var_list):
+    """Detect if expression corresponds to clip bound of the vars
+
+    Parameters
+    ----------
+    expr : Expr
+        The expression to be matched.
+
+    var_list : List[tvm.tirx.Var]
+        A list of variables.
+
+    Returns
+    -------
+    coeff : List[Expr]
+        `concat([min_value[i], max_value[i]] for i, v in enumerate(var_list))`
+        An empty list if the match failed.
+    """
+    return _ffi_api.DetectClipBound(expr, var_list)