1 /* Copyright 2020 The TensorFlow Authors. All Rights Reserved.
2
3 Licensed under the Apache License, Version 2.0 (the "License");
4 you may not use this file except in compliance with the License.
5 You may obtain a copy of the License at
6
7 http://www.apache.org/licenses/LICENSE-2.0
8
9 Unless required by applicable law or agreed to in writing, software
10 distributed under the License is distributed on an "AS IS" BASIS,
11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 See the License for the specific language governing permissions and
13 limitations under the License.
14 ==============================================================================*/
15
16 // Fuse tf.Op + tf.BiasAdd and legalized to TOSA
17
18 #include <climits>
19 #include <cstddef>
20 #include <cstdint>
21 #include <iterator>
22 #include <numeric>
23
24 #include "mlir/Dialect/Tosa/IR/TosaOps.h" // from @llvm-project
25 #include "mlir/IR/MLIRContext.h" // from @llvm-project
26 #include "mlir/Pass/Pass.h" // from @llvm-project
27 #include "mlir/Support/LogicalResult.h" // from @llvm-project
28 #include "mlir/Transforms/GreedyPatternRewriteDriver.h" // from @llvm-project
29 #include "tensorflow/compiler/mlir/lite/quantization/ir/QuantOps.h"
30 #include "tensorflow/compiler/mlir/tensorflow/ir/tf_ops.h"
31 #include "tensorflow/compiler/mlir/tosa/transforms/legalize_common.h"
32 #include "tensorflow/compiler/mlir/tosa/transforms/passes.h"
33
34 #define PASS_NAME "tosa-fuse-bias-tf"
35 #define DEBUG_TYPE PASS_NAME
36
37 namespace mlir {
38 namespace tosa {
39 namespace {
40
41 class FuseBiasTF : public TosaFusebiasTFPassBase<FuseBiasTF> {
42 public:
FuseBiasTF()43 explicit FuseBiasTF() {}
44 void runOnOperation() override;
45 };
46
47 struct ConvertTFBiasAddOp : public RewritePattern {
ConvertTFBiasAddOpmlir::tosa::__anon750d0cda0111::ConvertTFBiasAddOp48 explicit ConvertTFBiasAddOp(MLIRContext* context)
49 : RewritePattern(TF::BiasAddOp::getOperationName(), 1, context) {}
50 LogicalResult matchAndRewrite(Operation* op,
51 PatternRewriter& rewriter) const override;
52 };
53
54 // Replaces the following pattern:
55 // %1 = tf.Conv2D (%ifm, %filter)
56 // %2 = tf.BiasAdd(%1, %bias)
57 // with
58 // %1 = tosa.conv2d(%ifm, %filter, %bias)
59 // This can also be done using the pair ot Pat<> options in
60 // tf_optimize_patterns.td
61 // However, this explicit code can handle both when the LHS or RHS is the
62 // defining conv2d op.
63 // TODO: support other pattern. e.g. tf.DepthwiseConv2DNative
64
matchAndRewrite(Operation * op,PatternRewriter & rewriter) const65 LogicalResult ConvertTFBiasAddOp::matchAndRewrite(
66 Operation* op, PatternRewriter& rewriter) const {
67 auto tf_biasadd_op = cast<TF::BiasAddOp>(op);
68
69 auto output_type =
70 tf_biasadd_op.getResult().getType().dyn_cast<RankedTensorType>();
71 // Not a ranked tensor output
72 if (!output_type) return failure();
73
74 auto value = tf_biasadd_op.value();
75 auto bias = tf_biasadd_op.bias();
76
77 TF::Conv2DOp tf_conv2d_op =
78 dyn_cast_or_null<TF::Conv2DOp>(value.getDefiningOp());
79
80 if (!tf_conv2d_op) {
81 return failure();
82 }
83
84 // Sanity check to confirm rhs() has the expected shape of bias
85 auto filter_shape =
86 tf_conv2d_op.filter().getType().dyn_cast<RankedTensorType>().getShape();
87
88 auto bias_shape = bias.getType().dyn_cast<RankedTensorType>().getShape();
89
90 // Bias dimension must match filter output channels, where tf.conv2d's filter
91 // is [H, W, I, O]
92 if (filter_shape.back() != bias_shape.back()) return failure();
93
94 // Bias tensor that feeds into tosa.conv2d must be rank 1
95 if (bias_shape.size() != 1) return failure();
96
97 auto result = convertTFConv2DCommon(
98 rewriter, op, output_type, tf_conv2d_op.input(), tf_conv2d_op.filter(),
99 bias, tf_conv2d_op.strides(), tf_conv2d_op.dilations(),
100 tf_conv2d_op.explicit_paddings(), tf_conv2d_op.padding(),
101 tf_conv2d_op.data_format());
102
103 if (!result) return failure();
104
105 rewriter.replaceOp(op, {result.getValue()});
106
107 return success();
108 }
109
runOnOperation()110 void FuseBiasTF::runOnOperation() {
111 RewritePatternSet patterns(&getContext());
112 auto* ctx = &getContext();
113 auto func = getOperation();
114
115 // Add the generated patterns to the list.
116 patterns.add<ConvertTFBiasAddOp>(ctx);
117 (void)applyPatternsAndFoldGreedily(func, std::move(patterns));
118 }
119
120 } // anonymous namespace
121
createFuseBiasTFPass()122 std::unique_ptr<OperationPass<func::FuncOp>> createFuseBiasTFPass() {
123 return std::make_unique<FuseBiasTF>();
124 }
125
126 } // namespace tosa
127
128 } // namespace mlir
129