[nnkit] Introduce 'tflite' backend (#408)

This commit introduces 'tflite' bakckend, which loads 'tflite' model
file and runs inference.

The core part of this backend is extracted as nnkit_support_tflite
library, which allows its reuse in the future.

Signed-off-by: Jonghyun Park <jh1302.park@samsung.com>

diff --git a/contrib/nnkit/backends/tflite/Backend.cpp b/contrib/nnkit/backends/tflite/Backend.cpp
new file mode 100644 (file)
index 0000000..2250115
--- /dev/null
+++ b/contrib/nnkit/backends/tflite/Backend.cpp
@@ -0,0 +1,47 @@
+#include "nnkit/support/tflite/AbstractBackend.h"
+
+#include <tensorflow/contrib/lite/kernels/register.h>
+#include <tensorflow/contrib/lite/model.h>
+
+#include <stdexcept>
+
+namespace
+{
+
+class GenericBackend final : public nnkit::support::tflite::AbstractBackend
+{
+public:
+  GenericBackend(const std::string &path)
+  {
+    ::tflite::StderrReporter error_reporter;
+
+    _model = ::tflite::FlatBufferModel::BuildFromFile(path.c_str(), &error_reporter);
+
+    ::tflite::ops::builtin::BuiltinOpResolver resolver;
+    ::tflite::InterpreterBuilder builder(*_model, resolver);
+
+    if (kTfLiteOk != builder(&_interp))
+    {
+      throw std::runtime_error{"Failed to build a tflite interpreter"};
+    }
+
+    _interp->SetNumThreads(1);
+  }
+
+public:
+  ::tflite::Interpreter &interpreter(void) override { return *_interp; }
+
+private:
+  std::unique_ptr<::tflite::FlatBufferModel> _model;
+  std::unique_ptr<::tflite::Interpreter> _interp;
+};
+
+}
+
+#include <nnkit/CmdlineArguments.h>
+#include <nncc/foundation/Memory.h>
+
+extern "C" std::unique_ptr<nnkit::Backend> make_backend(const nnkit::CmdlineArguments &args)
+{
+  return nncc::foundation::make_unique<GenericBackend>(args.at(0));
+}

diff --git a/contrib/nnkit/backends/tflite/CMakeLists.txt b/contrib/nnkit/backends/tflite/CMakeLists.txt
new file mode 100644 (file)
index 0000000..31606b1
--- /dev/null
+++ b/contrib/nnkit/backends/tflite/CMakeLists.txt
@@ -0,0 +1,6 @@
+if(NOT TARGET nnkit_support_tflite)
+  return()
+endif(NOT TARGET nnkit_support_tflite)
+
+add_library(nnkit_tflite_backend SHARED Backend.cpp)
+target_link_libraries(nnkit_tflite_backend nnkit_support_tflite)

diff --git a/contrib/nnkit/libs/CMakeLists.txt b/contrib/nnkit/libs/CMakeLists.txt
index c1f4b8a..5ea6cda 100644 (file)
--- a/contrib/nnkit/libs/CMakeLists.txt
+++ b/contrib/nnkit/libs/CMakeLists.txt
@@ -1 +1 @@
-add_subdirectory(intf)
+add_subdirectories()

diff --git a/contrib/nnkit/libs/support/CMakeLists.txt b/contrib/nnkit/libs/support/CMakeLists.txt
new file mode 100644 (file)
index 0000000..5ea6cda
--- /dev/null
+++ b/contrib/nnkit/libs/support/CMakeLists.txt
@@ -0,0 +1 @@
+add_subdirectories()

diff --git a/contrib/nnkit/libs/support/tflite/CMakeLists.txt b/contrib/nnkit/libs/support/tflite/CMakeLists.txt
new file mode 100644 (file)
index 0000000..4484899
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/CMakeLists.txt
@@ -0,0 +1,13 @@
+nncc_find_package(TensorFlowLite QUIET)
+
+if(NOT TensorFlowLite_FOUND)
+  return()
+endif(NOT TensorFlowLite_FOUND)
+
+file(GLOB_RECURSE SOURCES "src/*.cpp")
+
+add_library(nnkit_support_tflite STATIC ${SOURCES})
+set_target_properties(nnkit_support_tflite PROPERTIES POSITION_INDEPENDENT_CODE ON)
+target_include_directories(nnkit_support_tflite PUBLIC include)
+target_link_libraries(nnkit_support_tflite nnkit_intf_backend)
+target_link_libraries(nnkit_support_tflite tensorflowlite)

diff --git a/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/AbstractBackend.h b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/AbstractBackend.h
new file mode 100644 (file)
index 0000000..7c611a5
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/AbstractBackend.h
@@ -0,0 +1,32 @@
+#ifndef __NNKIT_SUPPORT_TFLITE_ABSTRACT_BACKEND_H__
+#define __NNKIT_SUPPORT_TFLITE_ABSTRACT_BACKEND_H__
+
+#include <nnkit/Backend.h>
+#include <tensorflow/contrib/lite/interpreter.h>
+
+namespace nnkit
+{
+namespace support
+{
+namespace tflite
+{
+
+class AbstractBackend : public nnkit::Backend
+{
+public:
+  virtual ~AbstractBackend() = default;
+
+public:
+  virtual ::tflite::Interpreter &interpreter(void) = 0;
+
+public:
+  void prepare(const std::function<void (TensorContext &)> &f) override;
+  void run(void) override;
+  void teardown(const std::function<void (TensorContext &)> &f) override;
+};
+
+} // namespace tflite
+} // namespace support
+} // namespace nnkit
+
+#endif // __NNKIT_SUPPORT_TFLITE_ABSTRACT_BACKEND_H__

diff --git a/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorContext.h b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorContext.h
new file mode 100644 (file)
index 0000000..b2dbafd
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorContext.h
@@ -0,0 +1,56 @@
+#ifndef __NNKIT_SUPPORT_TFLITE_TENSOR_CONTEXT_H__
+#define __NNKIT_SUPPORT_TFLITE_TENSOR_CONTEXT_H__
+
+#include "nnkit/support/tflite/TensorSet.h"
+
+#include <nnkit/TensorContext.h>
+
+namespace nnkit
+{
+namespace support
+{
+namespace tflite
+{
+
+class TensorContext final : public nnkit::TensorContext
+{
+public:
+  TensorContext(TensorSet &tensors) : _tensors(tensors)
+  {
+    // DO NOTHING
+  }
+
+public:
+  uint32_t size(void) const override
+  {
+    return _tensors.size();
+  }
+
+public:
+  std::string name(uint32_t n) const override
+  {
+    return _tensors.at(n)->name;
+  }
+
+public:
+  nncc::core::ADT::tensor::Shape shape(uint32_t n) const override;
+
+public:
+  // Float (fp32) tensor support
+  bool isFloatTensor(uint32_t n) const override
+  {
+    return _tensors.at(n)->type == kTfLiteFloat32;
+  }
+
+  void getMutableFloatTensor(uint32_t n, const TensorContext::TypedAccessor<float> &f) override;
+  void getConstFloatTensor(uint32_t n, const TensorContext::TypedReader<float> &f) const override;
+
+private:
+  TensorSet &_tensors;
+};
+
+} // namespace tflite
+} // namespace support
+} // namespace nnkit
+
+#endif // __NNKIT_SUPPORT_TFLITE_TENSOR_CONTEXT_H__

diff --git a/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorSet.h b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorSet.h
new file mode 100644 (file)
index 0000000..d249ae1
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorSet.h
@@ -0,0 +1,29 @@
+#ifndef __NNKIT_SUPPORT_TFLITE_TENSOR_SET_H__
+#define __NNKIT_SUPPORT_TFLITE_TENSOR_SET_H__
+
+#include <tensorflow/contrib/lite/context.h>
+
+#include <cstdint>
+
+namespace nnkit
+{
+namespace support
+{
+namespace tflite
+{
+
+struct TensorSet
+{
+  virtual ~TensorSet() = default;
+
+  virtual uint32_t size(void) const = 0;
+
+  virtual TfLiteTensor *at(uint32_t n) const = 0;
+};
+
+} // namespace tflite
+} // namespace support
+} // namespace nnkit
+
+
+#endif // __NNKIT_SUPPORT_TFLITE_TENSOR_SET_H__

diff --git a/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorSets.h b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorSets.h
new file mode 100644 (file)
index 0000000..3dfcfbc
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorSets.h
@@ -0,0 +1,61 @@
+#ifndef __NNKIT_SUPPORT_TFLITE_TENSOR_SETS_H__
+#define __NNKIT_SUPPORT_TFLITE_TENSOR_SETS_H__
+
+#include "nnkit/support/tflite/TensorSet.h"
+
+#include <tensorflow/contrib/lite/interpreter.h>
+
+namespace nnkit
+{
+namespace support
+{
+namespace tflite
+{
+
+class InputTensorSet final : public TensorSet
+{
+public:
+  explicit InputTensorSet(::tflite::Interpreter &interp) : _interp(interp)
+  {
+    // DO NOTHING
+  }
+
+public:
+  uint32_t size(void) const override { return _interp.inputs().size(); }
+
+public:
+  TfLiteTensor *at(uint32_t n) const override
+  {
+    return _interp.tensor(_interp.inputs().at(n));
+  }
+
+private:
+  ::tflite::Interpreter &_interp;
+};
+
+class OutputTensorSet final : public TensorSet
+{
+public:
+  OutputTensorSet(::tflite::Interpreter &interp) : _interp(interp)
+  {
+    // DO NOTHING
+  }
+
+public:
+  uint32_t size(void) const override { return _interp.outputs().size(); }
+
+public:
+  TfLiteTensor *at(uint32_t n) const override
+  {
+    return _interp.tensor(_interp.outputs().at(n));
+  }
+
+private:
+  ::tflite::Interpreter &_interp;
+};
+
+} // namespace tflite
+} // namespace support
+} // namespace nnkit
+
+#endif // __NNKIT_SUPPORT_TFLITE_TENSOR_SETS_H__

diff --git a/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorUtils.h b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorUtils.h
new file mode 100644 (file)
index 0000000..6a2a363
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/include/nnkit/support/tflite/TensorUtils.h
@@ -0,0 +1,20 @@
+#ifndef __NNKIT_SUPPORT_TENSOR_UTILS_H__
+#define __NNKIT_SUPPORT_TENSOR_UTILS_H__
+
+#include <tensorflow/contrib/lite/context.h>
+#include <nncc/core/ADT/tensor/Shape.h>
+
+namespace nnkit
+{
+namespace support
+{
+namespace tflite
+{
+
+nncc::core::ADT::tensor::Shape tensor_shape(const TfLiteTensor *t);
+
+} // namespace tflite
+} // namespace support
+} // namespace nnkit
+
+#endif // __NNKIT_SUPPORT_TFLITE_TENSOR_UTILS_H__

diff --git a/contrib/nnkit/libs/support/tflite/src/Backend.cpp b/contrib/nnkit/libs/support/tflite/src/Backend.cpp
new file mode 100644 (file)
index 0000000..241ed6e
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/src/Backend.cpp
@@ -0,0 +1,42 @@
+#include "nnkit/support/tflite/AbstractBackend.h"
+#include "nnkit/support/tflite/TensorSets.h"
+#include "nnkit/support/tflite/TensorContext.h"
+
+#include <cassert>
+
+static inline void ensure(TfLiteStatus status)
+{
+  assert(status == kTfLiteOk);
+}
+
+namespace nnkit
+{
+namespace support
+{
+namespace tflite
+{
+
+void AbstractBackend::prepare(const std::function<void (nnkit::TensorContext &)> &f)
+{
+  ensure(interpreter().AllocateTensors());
+
+  InputTensorSet inputs(interpreter());
+  TensorContext ctx(inputs);
+  f(ctx);
+}
+
+void AbstractBackend::run(void)
+{
+  ensure(interpreter().Invoke());
+}
+
+void AbstractBackend::teardown(const std::function<void (nnkit::TensorContext &)> &f)
+{
+  OutputTensorSet outputs(interpreter());
+  TensorContext ctx(outputs);
+  f(ctx);
+}
+
+} // namespace tflite
+} // namespace support
+} // namespace nnkit

diff --git a/contrib/nnkit/libs/support/tflite/src/TensorContext.cpp b/contrib/nnkit/libs/support/tflite/src/TensorContext.cpp
new file mode 100644 (file)
index 0000000..e1ea762
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/src/TensorContext.cpp
@@ -0,0 +1,47 @@
+#include "nnkit/support/tflite/TensorContext.h"
+#include "nnkit/support/tflite/TensorUtils.h"
+
+#include <nncc/core/ADT/tensor/LexicalLayout.h>
+#include <nncc/core/ADT/tensor/Overlay.h>
+
+namespace nnkit
+{
+namespace support
+{
+namespace tflite
+{
+
+nncc::core::ADT::tensor::Shape TensorContext::shape(uint32_t n) const
+{
+    return tensor_shape(_tensors.at(n));
+}
+
+void TensorContext::getMutableFloatTensor(uint32_t n, const nnkit::TensorContext::TypedAccessor<float> &f)
+{
+  using nncc::core::ADT::tensor::LexicalLayout;
+  using nncc::core::ADT::tensor::make_overlay;
+
+  auto t = _tensors.at(n);
+
+  float *data = reinterpret_cast<float *>(t->data.f);
+  auto overlay = make_overlay<float, LexicalLayout>(shape(n), data);
+
+  f(*this, n, overlay);
+}
+
+void TensorContext::getConstFloatTensor(uint32_t n, const nnkit::TensorContext::TypedReader<float> &f) const
+{
+  using nncc::core::ADT::tensor::LexicalLayout;
+  using nncc::core::ADT::tensor::make_overlay;
+
+  auto t = _tensors.at(n);
+
+  float *data = reinterpret_cast<float *>(t->data.f);
+  auto overlay = make_overlay<float, LexicalLayout>(shape(n), data);
+
+  f(*this, n, overlay);
+}
+
+} // namespace tflite
+} // namespace support
+} // namespace nnkit

diff --git a/contrib/nnkit/libs/support/tflite/src/TensorUtils.cpp b/contrib/nnkit/libs/support/tflite/src/TensorUtils.cpp
new file mode 100644 (file)
index 0000000..6f3262c
--- /dev/null
+++ b/contrib/nnkit/libs/support/tflite/src/TensorUtils.cpp
@@ -0,0 +1,27 @@
+#include "nnkit/support/tflite/TensorUtils.h"
+
+namespace nnkit
+{
+namespace support
+{
+namespace tflite
+{
+
+nncc::core::ADT::tensor::Shape tensor_shape(const TfLiteTensor *t)
+{
+  nncc::core::ADT::tensor::Shape shape;
+
+  const int rank = t->dims->size;
+
+  shape.resize(rank);
+  for (int axis = 0; axis < rank; ++axis)
+  {
+    shape.dim(axis) = t->dims->data[axis];
+  }
+
+  return shape;
+}
+
+} // namespace tflite
+} // namespace support
+} // namespace nnkit