1/* Copyright 2022 The TensorFlow Authors. All Rights Reserved.
2
3Licensed under the Apache License, Version 2.0 (the "License");
4you may not use this file except in compliance with the License.
5You may obtain a copy of the License at
6
7 http://www.apache.org/licenses/LICENSE-2.0
8
9Unless required by applicable law or agreed to in writing, software
10distributed under the License is distributed on an "AS IS" BASIS,
11WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12See the License for the specific language governing permissions and
13limitations under the License.
14==============================================================================*/
15
16#include "tensorflow/dtensor/mlir/op_utils.h"
17
18#include <string>
19
20#include "llvm/Support/raw_ostream.h"
21
22namespace tensorflow {
23namespace dtensor {
24
25// OpHash prints the `op` into a string and performs hash value on the output
26// string.
27//
28// The `print` includes the full representation of the `op`, e.g., target
29// register, layout, shape, etc. This should be sufficient to uniquely
30// identify the operation in most cases. This does not capture function scope
31// (identical op in 2 separate functions).
32uint64_t OpHash(mlir::Operation* op) {
33 std::string output;
34 llvm::raw_string_ostream output_stream(output);
35 mlir::OpPrintingFlags flags;
36 flags.elideLargeElementsAttrs(1024);
37 op->print(output_stream, flags);
38 return llvm::hash_value(output);
39}
40
41// Returns FuncOp if `op` is a callable.
42absl::optional<mlir::func::FuncOp> MaybeFindFunction(mlir::Operation* op) {
43 auto call_op = llvm::dyn_cast<mlir::CallOpInterface>(op);
44 if (!call_op) return absl::nullopt;
45
46 mlir::CallInterfaceCallable callable = call_op.getCallableForCallee();
47 mlir::SymbolRefAttr sym = callable.dyn_cast<mlir::SymbolRefAttr>();
48 if (!sym) return absl::nullopt;
49
50 mlir::func::FuncOp func = llvm::dyn_cast<mlir::func::FuncOp>(
51 mlir::SymbolTable::lookupNearestSymbolFrom(op, sym));
52 if (!func) return absl::nullopt;
53
54 return func;
55}
56
57void RemoveDTensorLayoutOp(mlir::TF::DTensorLayout layout) {
58 layout.output().replaceAllUsesWith(layout.input());
59 layout.erase();
60}
61
62} // namespace dtensor
63} // namespace tensorflow
64