1 | /* |
2 | * Licensed to the Apache Software Foundation (ASF) under one |
3 | * or more contributor license agreements. See the NOTICE file |
4 | * distributed with this work for additional information |
5 | * regarding copyright ownership. The ASF licenses this file |
6 | * to you under the Apache License, Version 2.0 (the |
7 | * "License"); you may not use this file except in compliance |
8 | * with the License. You may obtain a copy of the License at |
9 | * |
10 | * http://www.apache.org/licenses/LICENSE-2.0 |
11 | * |
12 | * Unless required by applicable law or agreed to in writing, |
13 | * software distributed under the License is distributed on an |
14 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
15 | * KIND, either express or implied. See the License for the |
16 | * specific language governing permissions and limitations |
17 | * under the License. |
18 | */ |
19 | |
20 | /*! |
21 | * \file src/relay/collage/mock_cost_estimator.cc |
22 | * \brief A mock CostEstimator to support unit tests. |
23 | */ |
24 | |
25 | #include "./mock_cost_estimator.h" |
26 | |
27 | #include <tvm/relay/expr_functor.h> |
28 | |
29 | namespace tvm { |
30 | namespace relay { |
31 | namespace collage { |
32 | |
33 | TVM_REGISTER_OBJECT_TYPE(MockCostEstimatorNode); |
34 | |
35 | namespace { |
36 | |
37 | /*! |
38 | * \brief Visitor to accumulate the costs of all calls to operators in an expression. |
39 | */ |
40 | class MockEstimationVisitor : private ExprVisitor { |
41 | public: |
42 | MockEstimationVisitor(double op_cost, double fusion_benefit) |
43 | : op_cost_(op_cost), fusion_benefit_(fusion_benefit) {} |
44 | |
45 | double EstimateCost(const Expr& body) { |
46 | VisitExpr(body); |
47 | return cost_; |
48 | } |
49 | |
50 | private: |
51 | /*! \brief The assumed baseline cost of each operator call. */ |
52 | double op_cost_; |
53 | /*! |
54 | * \brief The factor by which each operator call cost is to be changed for every other |
55 | * operator call in the same group. |
56 | */ |
57 | double fusion_benefit_; |
58 | /*! \brief The number of operator calls seen so far. */ |
59 | size_t num_ops_ = 0; |
60 | /*! \brief Accumulate overall cost. */ |
61 | double cost_ = 0.0; |
62 | |
63 | void VisitExpr_(const CallNode* call_node) final { |
64 | if (call_node->op->IsInstance<OpNode>()) { |
65 | // Account for number of ops seens os far. |
66 | cost_ += op_cost_ * pow(fusion_benefit_, static_cast<double>(num_ops_)); |
67 | num_ops_++; |
68 | } |
69 | ExprVisitor::VisitExpr_(call_node); |
70 | } |
71 | |
72 | void VisitExpr_(const FunctionNode* function_node) final { |
73 | // No "Compiler" functions can be inlined. |
74 | ICHECK(!function_node->GetAttr<String>(attr::kCompiler).defined()) |
75 | << "All Compiler functions should have been outlined when preparing to estimate costs" ; |
76 | ExprVisitor::VisitExpr_(function_node); |
77 | } |
78 | }; |
79 | |
80 | } // namespace |
81 | |
82 | Cost MockCostEstimatorNode::Estimate(const IRModule& mod, const Target& target) const { |
83 | // Limit the number of estimations. |
84 | ICHECK(max_estimates_->value == 0 || num_estimates_ < static_cast<size_t>(max_estimates_->value)) |
85 | << "At most " << max_estimates_->value |
86 | << " non-trivial distinct candidates should have been generated." ; |
87 | ++num_estimates_; |
88 | double op_cost = static_cast<double>(target_costs_.at(target->kind->name)->value); |
89 | double cost = 0.0; |
90 | for (const auto& kv : mod->functions) { |
91 | if (const auto* function_node = kv.second.as<FunctionNode>()) { |
92 | auto function = GetRef<Function>(function_node); |
93 | if (kv.first->name_hint == "main" ) { |
94 | // Only tensor args are allowed to main. |
95 | for (const auto& param : function->params) { |
96 | ICHECK(param->type_annotation->IsInstance<TensorTypeNode>()) |
97 | << "Any tuple-of-tensor arguments should have been eta-exanded when preparing to " |
98 | "estimate costs" ; |
99 | } |
100 | } |
101 | cost += MockEstimationVisitor(op_cost, /*fusion_benefit=*/0.9).EstimateCost(function->body); |
102 | } |
103 | } |
104 | return Cost::Value(cost); |
105 | } |
106 | |
107 | MockCostEstimator::MockCostEstimator(Map<String, Integer> target_costs, Integer max_estimates) { |
108 | auto node = make_object<MockCostEstimatorNode>(); |
109 | node->target_costs_ = std::move(target_costs); |
110 | node->max_estimates_ = std::move(max_estimates); |
111 | data_ = std::move(node); |
112 | } |
113 | |
114 | TVM_REGISTER_GLOBAL("relay.collage.MockCostEstimator" ) |
115 | .set_body_typed([](Map<String, Integer> target_costs, Integer max_estimates) { |
116 | return MockCostEstimator(std::move(target_costs), std::move(max_estimates)); |
117 | }); |
118 | |
119 | } // namespace collage |
120 | } // namespace relay |
121 | } // namespace tvm |
122 | |