[Parser] Core Parser (apache#40)

python/tvm/script/builder/__init__.py

@@ -16,7 +16,5 @@
 # under the License.
 # pylint: disable=unused-import
 """Namespace for the TVMScript Builder API."""
-
-
 from .builder import Builder, def_, def_many
 from .frame import Frame, IRModuleFrame

python/tvm/script/builder/tir/axis.py

@@ -36,3 +36,7 @@ def reduce(dom, binding, dtype="int32") -> IterVar:
 
 def remap(kinds, bindings, dtype="int32") -> IterVar:
     return _ffi_api.AxisRemap(kinds, bindings, dtype)  # pylint: disable=no-member # type: ignore
+
+
+S = spatial
+R = reduce

python/tvm/script/builder/tir/prim_func_frame.py

@@ -21,6 +21,7 @@
 from tvm.tir.buffer import Buffer
 from tvm.tir.expr import Var
 
+from ..builder import Builder
 from . import _ffi_api
 from .base import TIRFrame
 
@@ -36,3 +37,6 @@ def prim_func(name) -> PrimFuncFrame:
 
 def arg(name, obj) -> Union[Var, Buffer]:
     return _ffi_api.Arg(name, obj)  # pylint: disable=no-member # type: ignore
+
+
+setattr(prim_func, "dispatch_token", "tir")

python/tvm/script/parse/__init__.py

@@ -0,0 +1,19 @@
+# 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 Licens.
+"""The parser"""
+from . import dispatch, parser, tir
+from .entry import parse

python/tvm/script/parse/dispatch.py

@@ -0,0 +1,67 @@
+# 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.
+"""The dispatcher"""
+
+import ast
+from typing import TYPE_CHECKING, Callable, Dict, Optional, Tuple
+
+if TYPE_CHECKING:
+    from .parser import Parser
+
+
+ParseMethod = Callable[
+    ["Parser", ast.AST],
+    None,
+]
+
+
+class DispatchTable:
+    """Dispatch table for parse methods"""
+
+    _instance: Optional["DispatchTable"] = None
+    table: Dict[Tuple[str, str], ParseMethod]
+
+    def __init__(self):
+        self.table = {}
+
+
+DispatchTable._instance = DispatchTable()  # pylint: disable=protected-access
+
+
+def register(
+    token: str,
+    type_name: str,
+):
+    """Register a method for a dispatch token and type name"""
+
+    def f(method: ParseMethod):
+        DispatchTable._instance.table[  # pylint: disable=protected-access
+            (token, type_name)
+        ] = method
+
+    return f
+
+
+def get(
+    token: str,
+    type_name: str,
+    default: Optional[ParseMethod] = None,
+) -> Optional[ParseMethod]:
+    return DispatchTable._instance.table.get(  # pylint: disable=protected-access
+        (token, type_name),
+        default,
+    )

python/tvm/script/parse/entry.py

@@ -0,0 +1,84 @@
+# 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.
+"""The entry point of TVM parser."""
+import ast
+import inspect
+from typing import Any, Dict, Optional, Union
+
+from ..builder import Builder
+from .parser import Parser
+
+
+class SourceCode:
+    source_name: str
+    start_line: int
+    start_column: int
+    source: str
+    full_source: str
+
+    def __init__(self, program: Union[str, ast.AST]):
+        if isinstance(program, str):
+            self.source_name = "<str>"
+            self.start_line = 1
+            self.start_column = 0
+            self.source = program
+            self.full_source = program
+        else:
+            self.source_name = inspect.getsourcefile(program)  # type: ignore
+            lines, self.start_line = inspect.getsourcelines(program)  # type: ignore
+
+            if lines:
+                self.start_column = len(lines[0]) - len(lines[0].lstrip())
+            else:
+                self.start_column = 0
+            if self.start_column and lines:
+                self.source = "\n".join([l[self.start_column :].rstrip() for l in lines])
+            else:
+                self.source = ""
+            try:
+                # It will cause a problem when running in Jupyter Notebook.
+                # `mod` will be <module '__main__'>, which is a built-in module
+                # and `getsource` will throw a TypeError
+                mod = inspect.getmodule(program)
+                if mod:
+                    self.full_source = inspect.getsource(mod)
+                else:
+                    self.full_source = self.source
+            except TypeError:
+                # It's a work around for Jupyter problem.
+                # Since `findsource` is an internal API of inspect, we just use it
+                # as a fallback method.
+                src, _ = inspect.findsource(program)  # type: ignore
+                self.full_source = "".join(src)
+
+    def as_ast(self) -> ast.AST:
+        return ast.parse(self.source)
+
+
+def parse(
+    program: Union[ast.AST, Any, str],
+    extra_vars: Optional[Dict[str, Any]] = None,
+):
+    program_ast = SourceCode(program).as_ast()
+    parser = Parser()
+    with Builder() as builder:
+        with parser.var_table.with_frame():
+            if extra_vars:
+                for k, v in extra_vars.items():
+                    parser.var_table.add(k, v)
+            parser.visit(program_ast)
+    return builder.get()

python/tvm/script/parse/evaluator.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.
+"""AST Evaluation"""
+import ast
+from typing import Any, Dict, Optional, Union
+
+
+def eval_expr(
+    node: Union[ast.expr, ast.Expression],
+    dict_globals: Optional[Dict[str, Any]],
+) -> Any:
+    if isinstance(node, ast.expr):
+        node = ast.Expression(body=node)
+    assert isinstance(node, ast.Expression)
+    if dict_globals is None:
+        dict_globals = {}
+    node = ast.fix_missing_locations(node)
+    exe = compile(node, filename="<ast>", mode="eval")
+    return eval(exe, dict_globals)  # pylint: disable=eval-used
+
+
+def eval_assign(
+    target: ast.expr,
+    source: Any,
+) -> Dict[str, Any]:
+    assert isinstance(target, ast.expr)
+    RHS_VAR_NAME = "__tvm_rhs_var__"  # pylint: disable=invalid-name
+    rhs_var_name = RHS_VAR_NAME
+    dict_locals = {rhs_var_name: source}
+    mod = ast.fix_missing_locations(
+        ast.Module(
+            body=[
+                ast.Assign(
+                    targets=[target],
+                    value=ast.Name(
+                        id=rhs_var_name,
+                        ctx=ast.Load(),
+                    ),
+                )
+            ],
+            type_ignores=[],
+        )
+    )
+    exe = compile(mod, filename="<ast>", mode="exec")
+    exec(exe, {}, dict_locals)  # pylint: disable=exec-used
+    del dict_locals[rhs_var_name]
+    return dict_locals

python/tvm/script/parse/parser.py

@@ -0,0 +1,109 @@
+# 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.
+"""The core parser"""
+import ast
+from typing import Any, Dict, List, Optional, Union
+
+from ..builder import def_
+from . import dispatch
+from .evaluator import eval_assign, eval_expr
+from .utils import deferred
+from .var_table import VarTable
+
+
+def _dispatch(self: "Parser", type_name: str) -> dispatch.ParseMethod:
+    for token in [self.dispatch_tokens[-1], "default"]:
+        func = dispatch.get(token=token, type_name=type_name, default=None)
+        if func is not None:
+            return func
+    return lambda self, node: self.generic_visit(node)
+
+
+def _handle_function(self: "Parser", node: ast.FunctionDef) -> None:
+    if not node.decorator_list:
+        self.report_error(node, "Function must be decorated")
+    # TODO: only the last decorator is parsed
+    decorator = self.eval_expr(node.decorator_list[-1])
+    if hasattr(decorator, "dispatch_token"):
+        token = decorator.dispatch_token
+        func = dispatch.get(token=token, type_name="FunctionDef", default=None)
+        if func is not None:
+            func(self, node)
+            return
+    self.report_error(node, "The parser does not understand the decorator")
+
+
+class Parser(ast.NodeVisitor):
+    """The TVMScript parser"""
+
+    dispatch_tokens: List[str]
+    var_table: VarTable
+
+    def __init__(self) -> None:
+        self.dispatch_tokens = ["default"]
+        self.var_table = VarTable()
+
+    def with_dispatch_token(self, token: str):
+        def pop_token():
+            self.dispatch_tokens.pop()
+
+        self.dispatch_tokens.append(token)
+        return deferred(pop_token)
+
+    def eval_expr(
+        self,
+        node: Union[ast.Expression, ast.expr],
+        extra_vars: Optional[Dict[str, Any]] = None,
+    ) -> Any:
+        var_values = self.var_table.get()
+        if extra_vars is not None:
+            for k, v in extra_vars.items():
+                var_values[k] = v
+        return eval_expr(node, var_values)
+
+    def eval_assign(
+        self,
+        target: ast.expr,
+        source: Any,
+    ) -> Dict[str, Any]:
+        var_values = eval_assign(target, source)
+        for k, v in var_values.items():
+            def_(k, v)
+            self.var_table.add(k, v)
+        return var_values
+
+    def report_error(self, node: ast.AST, msg: str) -> None:  # pylint: disable=no-self-use
+        raise SyntaxError(f"At {node.lineno}:{node.col_offset}: {msg}")
+
+    def visit_FunctionDef(self, node: ast.FunctionDef) -> Any:  # pylint: disable=invalid-name
+        _handle_function(self, node)
+
+    def visit_body(self, node: List[ast.stmt]) -> Any:
+        for stmt in node:
+            self.visit(stmt)
+
+    def visit_arguments(self, node: ast.arguments) -> Any:
+        _dispatch(self, "arguments")(self, node)
+
+    def visit_For(self, node: ast.For) -> Any:  # pylint: disable=invalid-name
+        _dispatch(self, "For")(self, node)
+
+    def visit_With(self, node: ast.With) -> Any:  # pylint: disable=invalid-name
+        _dispatch(self, "With")(self, node)
+
+    def visit_Assign(self, node: ast.Assign) -> Any:  # pylint: disable=invalid-name
+        _dispatch(self, "Assign")(self, node)

python/tvm/script/parse/tir/__init__.py

@@ -0,0 +1,17 @@
+# 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.
+from . import tir