1 //===- MLModelRunner.h ---- ML model runner interface -----------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 
10 #ifndef LLVM_ANALYSIS_MLMODELRUNNER_H
11 #define LLVM_ANALYSIS_MLMODELRUNNER_H
12 
13 #include "llvm/Analysis/TensorSpec.h"
14 #include "llvm/IR/PassManager.h"
15 
16 namespace llvm {
17 class LLVMContext;
18 
19 /// MLModelRunner interface: abstraction of a mechanism for evaluating a
20 /// tensorflow "saved model".
21 /// NOTE: feature indices are expected to be consistent all accross
22 /// MLModelRunners (pertaining to the same model), and also Loggers (see
23 /// TFUtils.h)
24 class MLModelRunner {
25 public:
26   // Disallows copy and assign.
27   MLModelRunner(const MLModelRunner &) = delete;
28   MLModelRunner &operator=(const MLModelRunner &) = delete;
29   virtual ~MLModelRunner() = default;
30 
31   template <typename T> T evaluate() {
32     return *reinterpret_cast<T *>(evaluateUntyped());
33   }
34 
35   template <typename T, typename I> T *getTensor(I FeatureID) {
36     return reinterpret_cast<T *>(
37         getTensorUntyped(static_cast<size_t>(FeatureID)));
38   }
39 
40   template <typename T, typename I> const T *getTensor(I FeatureID) const {
41     return reinterpret_cast<const T *>(
42         getTensorUntyped(static_cast<size_t>(FeatureID)));
43   }
44 
45   void *getTensorUntyped(size_t Index) { return InputBuffers[Index]; }
46   const void *getTensorUntyped(size_t Index) const {
47     return (const_cast<MLModelRunner *>(this))->getTensorUntyped(Index);
48   }
49 
50   enum class Kind : int { Unknown, Release, Development, NoOp, Interactive };
51   Kind getKind() const { return Type; }
52   virtual void switchContext(StringRef Name) {}
53 
54 protected:
55   MLModelRunner(LLVMContext &Ctx, Kind Type, size_t NrInputs)
56       : Ctx(Ctx), Type(Type), InputBuffers(NrInputs) {
57     assert(Type != Kind::Unknown);
58   }
59   virtual void *evaluateUntyped() = 0;
60 
61   void setUpBufferForTensor(size_t Index, const TensorSpec &Spec,
62                             void *Buffer) {
63     if (!Buffer) {
64       OwnedBuffers.emplace_back(Spec.getTotalTensorBufferSize());
65       Buffer = OwnedBuffers.back().data();
66     }
67     InputBuffers[Index] = Buffer;
68   }
69 
70   LLVMContext &Ctx;
71   const Kind Type;
72 
73 private:
74   std::vector<void *> InputBuffers;
75   std::vector<std::vector<char *>> OwnedBuffers;
76 };
77 } // namespace llvm
78 
79 #endif // LLVM_ANALYSIS_MLMODELRUNNER_H
80