Add bazel configs for some C APIs and pybinds

utils/bazel/torch-mlir-overlay/BUILD.bazel

@@ -2,7 +2,8 @@
 # See https://llvm.org/LICENSE.txt for license information.
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
-load("@llvm-project//mlir:tblgen.bzl", "gentbl_cc_library", "td_library")
+load("@llvm-project//mlir:build_defs.bzl", "mlir_c_api_cc_library")
+load("@llvm-project//mlir:tblgen.bzl", "gentbl_cc_library", "gentbl_filegroup", "td_library")
 load("@com_github_bazelbuild_buildtools//buildifier:def.bzl", "buildifier")
 
 package(
@@ -923,3 +924,96 @@ cc_binary(
         "@llvm-project//mlir:MlirOptLib",
     ],
 )
+
+# C API bindings
+mlir_c_api_cc_library(
+    name = "CAPITorchRegisterEverything",
+    srcs = ["lib/CAPI/Registration.cpp"],
+    hdrs = ["include/torch-mlir-c/Registration.h"],
+    capi_deps = ["@llvm-project//mlir:CAPIIR"],
+    deps = [
+        ":TorchMLIRInitAll",
+        "@llvm-project//mlir:AllPassesAndDialects",
+    ],
+)
+
+mlir_c_api_cc_library(
+    name = "CAPITorch",
+    srcs = ["lib/CAPI/Dialects.cpp"],
+    hdrs = ["include/torch-mlir-c/Dialects.h"],
+    capi_deps = ["@llvm-project//mlir:CAPIIR"],
+    deps = [":TorchMLIRTorchDialect"],
+)
+
+# These flags are needed for pybind11 to work.
+PYBIND11_COPTS = [
+    "-fexceptions",
+    "-frtti",
+]
+
+PYBIND11_FEATURES = [
+    # Cannot use header_modules (parse_headers feature fails).
+    "-use_header_modules",
+]
+
+# pybind11 extension module
+cc_binary(
+    name = "_torchMlir.so",
+    srcs = [
+        "include/torch-mlir-c/Registration.h",
+        "python/TorchMLIRModule.cpp",
+    ],
+    copts = PYBIND11_COPTS,
+    features = PYBIND11_FEATURES,
+    linkshared = 1,
+    linkstatic = 0,
+    deps = [
+        ":CAPITorch",
+        ":CAPITorchRegisterEverything",
+        "@llvm-project//mlir:CAPIIR",
+        "@llvm-project//mlir:MLIRBindingsPythonHeadersAndDeps",
+    ],
+)
+
+# python files
+td_library(
+    name = "TorchOpsPyTdFiles",
+    srcs = [":MLIRTorchOpsIncGenTdFiles"],
+    includes = ["include"],
+    deps = [
+        "@llvm-project//mlir:BuiltinDialectTdFiles",
+        "@llvm-project//mlir:OpBaseTdFiles",
+    ],
+)
+
+gentbl_filegroup(
+    name = "TorchOpsPyGen",
+    includes = ["include"],
+    tbl_outs = [
+        (
+            [
+                "-gen-python-op-bindings",
+                "-bind-dialect=torch",
+            ],
+            "python/torch_mlir/dialects/_torch_ops_gen.py",
+        ),
+    ],
+    tblgen = "@llvm-project//mlir:mlir-tblgen",
+    td_file = "python/torch_mlir/dialects/TorchBinding.td",
+    deps = [
+        ":TorchOpsPyTdFiles",
+        "@llvm-project//mlir:AttrTdFiles",
+    ],
+)
+
+filegroup(
+    name = "TorchOpsPyFiles",
+    srcs = [
+        ":TorchOpsPyGen",
+    ],
+)
+
+filegroup(
+    name = "TorchPyFiles",
+    srcs = glob(["python/**/*.py"]),
+)