Internal Change.

PiperOrigin-RevId: 175307445

1 files changed, 298 insertions, 0 deletions

diff --git a/tensorflow/contrib/lite/context.h b/tensorflow/contrib/lite/context.h
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+/* Copyright 2017 The TensorFlow Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+// This file defines a C API for implementing operations in tflite.
+// These operations can be defined using c++ but the interface between
+// the interpreter and the operations are C.
+//
+// Summary of abstractions
+// TF_LITE_ENSURE - Self-sufficient error checking
+// TfLiteStatus - Status reporting
+// TfLiteIntArray - stores tensor shapes (dims),
+// TfLiteContext - allows an op to access the tensors
+// TfLiteTensor - tensor (a multidimensional array)
+// TfLiteNode - a single node or operation
+// TfLiteRegistration - the implementation of a conceptual operation.
+//
+// Some abstractions in this file are created and managed by Interpreter.
+#ifndef THIRD_PARTY_TENSORFLOW_CONTRIB_LITE_CONTEXT_H_
+#define THIRD_PARTY_TENSORFLOW_CONTRIB_LITE_CONTEXT_H_
+
+#include <stdint.h>
+#include <stdlib.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif  // __cplusplus
+
+typedef enum { kTfLiteOk = 0, kTfLiteError = 1 } TfLiteStatus;
+
+#define kOptionalTensor (-1)
+
+// Fixed size list of integers. Used for dimensions and inputs/outputs tensor
+// indices
+typedef struct {
+  int size;
+// gcc 6.1+ have a bug where flexible members aren't properly handled
+// https://github.com/google/re2/commit/b94b7cd42e9f02673cd748c1ac1d16db4052514c
+#if !defined(__clang__) && defined(__GNUC__) && __GNUC__ == 6 && \
+    __GNUC_MINOR__ >= 1
+  int data[0];
+#else
+  int data[];
+#endif
+} TfLiteIntArray;
+
+// Create a array of a given `size` (uninitialized entries).
+// This returns a pointer, that you must free using TfLiteIntArrayFree().
+TfLiteIntArray* TfLiteIntArrayCreate(int size);
+
+// Check if two tensors are equal. Returns 1 if they are equal, 0 otherwise.
+int TfLiteIntArrayEqual(TfLiteIntArray* a, TfLiteIntArray* b);
+
+// Create a copy of an array passed as `src`.
+// You are expected to free memory with TfLiteIntArrayFree
+TfLiteIntArray* TfLiteIntArrayCopy(TfLiteIntArray* src);
+
+// Free memory of array `v`.
+void TfLiteIntArrayFree(TfLiteIntArray* v);
+
+// Since we must not depend on any libraries, define a minimal subset of
+// error macros while avoiding names that have pre-conceived meanings like
+// assert and check.
+
+// Check whether value is true, and if not return kTfLiteError from
+// the current function (and report the error string msg).
+#define TF_LITE_ENSURE_MSG(context, value, msg)            \
+  do {                                                     \
+    if (!(value)) {                                        \
+      (context)->ReportError((context), __FILE__ " " msg); \
+      return kTfLiteError;                                 \
+    }                                                      \
+  } while (0)
+
+// Check whether the value `a` is true, and if not return kTfLiteError from
+// the current function, while also reporting the location of the error.
+#define TF_LITE_ENSURE(context, a)                                          \
+  do {                                                                      \
+    if (!(a)) {                                                             \
+      (context)->ReportError((context), "%s:%d %s was not true.", __FILE__, \
+                             __LINE__, #a);                                 \
+      return kTfLiteError;                                                  \
+    }                                                                       \
+  } while (0)
+
+#define TF_LITE_ENSURE_STATUS(a) \
+  do {                           \
+    if ((a) != kTfLiteOk) {      \
+      return kTfLiteError;       \
+    }                            \
+  } while (0)
+
+// Check whether the value `a == b` is true, and if not return kTfLiteError from
+// the current function, while also reporting the location of the error.
+// `a` and `b` may be evaluated more than once, so no side effects or
+// extremely expensive computations should be done.
+#define TF_LITE_ENSURE_EQ(context, a, b)                                       \
+  do {                                                                         \
+    if ((a) != (b)) {                                                          \
+      (context)->ReportError((context), "%s:%d %s != %s (%d != %d)", __FILE__, \
+                             __LINE__, #a, #b, (a), (b));                      \
+      return kTfLiteError;                                                     \
+    }                                                                          \
+  } while (0)
+
+#define TF_LITE_ENSURE_OK(context, status) \
+  do {                                     \
+    if ((status) != kTfLiteOk) {           \
+      return status;                       \
+    }                                      \
+  } while (0)
+
+// Types supported by tensor
+typedef enum {
+  kTfLiteNoType = 0,
+  kTfLiteFloat32 = 1,
+  kTfLiteInt32 = 2,
+  kTfLiteUInt8 = 3,
+  kTfLiteInt64 = 4,
+  kTfLiteString = 5,
+} TfLiteType;
+
+// Parameters for asymmetric quantization. Quantized values can be converted
+// back to float using:
+//    real_value = scale * (quantized_value - zero_point);
+typedef struct {
+  float scale;
+  int32_t zero_point;
+} TfLiteQuantizationParams;
+
+// A union of points that points to memory for a given tensor.
+typedef union {
+  int* i32;
+  float* f;
+  char* raw;
+  const char* raw_const;
+  uint8_t* uint8;
+} TfLitePtrUnion;
+
+// Memory allocation strategies. kTfLiteMmapRo is for read-only memory-mapped
+// data (or data externally allocated). kTfLiteArenaRw is arena allocated
+// data. kTfLiteDynamic is for tensors that are allocated during evaluation.
+typedef enum {
+  kTfLiteMemNone = 0,
+  kTfLiteMmapRo,
+  kTfLiteArenaRw,
+  kTfLiteArenaRwPersistent,
+  kTfLiteDynamic,
+} TfLiteAllocationType;
+
+// An tensor in the interpreter system which is a wrapper around a buffer of
+// data including a dimensionality (or NULL if not currently defined).
+typedef struct {
+  // The data type specification for data stored in `data`. This affects
+  // what member of `data` union should be used.
+  TfLiteType type;
+  // A union of data pointers. The appropriate type should be used for a typed
+  // tensor based on `type`.
+  TfLitePtrUnion data;
+  // A pointer to a structure representing the dimensionality interpretation
+  // that the buffer should have. NOTE: the product of elements of `dims`
+  // and the element datatype size should be equal to `bytes` below.
+  TfLiteIntArray* dims;
+  // Quantization information.
+  TfLiteQuantizationParams params;
+  // How memory is mapped
+  //  kTfLiteMmapRo: Memory mapped read only.
+  //  i.e. weights
+  //  kTfLiteArenaRw: Arena allocated read write memory
+  //  (i.e. temporaries, outputs).
+  TfLiteAllocationType allocation_type;
+  // The number of bytes required to store the data of this Tensor. I.e.
+  // (bytes of each element) * dims[0] * ... * dims[n-1].  For example, if
+  // type is kTfLiteFloat32 and dims = {3, 2} then
+  // bytes = sizeof(float) * 3 * 2 = 4 * 3 * 2 = 24.
+  size_t bytes;
+
+  // An opaque pointer to a tflite::MMapAllocation
+  const void* allocation;
+
+  // Null-terminated name of this tensor.
+  const char* name;
+} TfLiteTensor;
+
+// Free memory of tensor `t`;
+void TfLiteTensorFree(TfLiteTensor* t);
+
+// Set all of a tensor's fields (and free any previously allocated data).
+void TfLiteTensorReset(TfLiteType type, const char* name, TfLiteIntArray* dims,
+                       TfLiteQuantizationParams quantization, char* buffer,
+                       size_t size, TfLiteAllocationType allocation_type,
+                       const void* allocation, TfLiteTensor* tensor);
+
+// Resize the allocated data of a (dynamic) tensor.
+void TfLiteTensorRealloc(size_t num_bytes, TfLiteTensor* tensor);
+
+typedef struct TfLiteContext {
+  // Number of tensors in the context.
+  int tensors_size;
+  // An tensor of tensors in the interpreter context (of length `tensors_size`)
+  TfLiteTensor* tensors;
+
+  // opaque full context ptr (an opaque c++ data structure)
+  void* impl_;
+
+  // Request memory pointer be resized. Updates dimensions on the tensor.
+  // NOTE: ResizeTensor takes ownership of newSize.
+  TfLiteStatus (*ResizeTensor)(struct TfLiteContext*, TfLiteTensor* tensor,
+                               TfLiteIntArray* new_size);
+  // Request that a error be reported with format string msg.
+  void (*ReportError)(struct TfLiteContext*, const char* msg, ...);
+
+  // Add `tensors_to_add` tensors, preserving pre-existing Tensor entries.  If
+  // non-null, the value pointed to by `first_new_tensor_index` will be set to
+  // the index of the first new tensor.
+  TfLiteStatus (*AddTensors)(struct TfLiteContext*, int tensors_to_add,
+                             int* first_new_tensor_index);
+
+  // TODO(ahentz): we should create a more general mechanism for this sort of
+  // library-global objects.
+  void* gemm_context;
+} TfLiteContext;
+
+// A structure representing an instance of a node.
+// This structure only exhibits the inputs, outputs and user defined data, not
+// other features like the type.
+typedef struct {
+  // Inputs to this node expressed as indices into the simulator's tensors.
+  TfLiteIntArray* inputs;
+
+  // Outputs to this node expressed as indices into the simulator's tensors.
+  TfLiteIntArray* outputs;
+
+  // Temporary tensors uses during the computations. This usually contains no
+  // tensors, but ops are allowed to change that if they need scratch space of
+  // any sort.
+  TfLiteIntArray* temporaries;
+
+  // Opaque data provided by the node implementer through `Registration.init`.
+  void* user_data;
+
+  // Opaque data provided to the node if the node is a builtin.
+  void* builtin_data;
+} TfLiteNode;
+
+typedef struct {
+  // Initializes the op from serialized data.
+  // If a built-in op:
+  //   `buffer` is the op's params data (TfLiteLSTMParams*).
+  //   `length` is zero.
+  // If custom op:
+  //   `buffer` is the op's `custom_options`.
+  //   `length` is the size of the buffer.
+  //
+  // Returns a type-punned (i.e. void*) opaque data (e.g. a primitive pointer
+  // or an instance of a struct).
+  //
+  // The returned pointer will be stored with the node in the `user_data` field,
+  // accessible within prepare and invoke functions below.
+  // NOTE: if the data is already in the desired format, simply implement this
+  // function to return `nullptr` and implement the free function to be a no-op.
+  void* (*init)(TfLiteContext* context, const char* buffer, size_t length);
+
+  // The pointer `buffer` is the data previously returned by an init invocation.
+  void (*free)(TfLiteContext* context, void* buffer);
+
+  // prepare is called when the inputs this node depends on have been resized.
+  // context->ResizeTensor() can be called to request output tensors to be
+  // resized.
+  //
+  // Returns kTfLiteOk on success.
+  TfLiteStatus (*prepare)(TfLiteContext* context, TfLiteNode* node);
+
+  // Execute the node (should read node->inputs and output to node->outputs).
+  // Returns kTfLiteOk on success.
+  TfLiteStatus (*invoke)(TfLiteContext* context, TfLiteNode* node);
+
+  // Builtin codes. If this kernel refers to a builtin this is the code
+  // of the builtin. This is so we can do marshaling to other frameworks like
+  // NN API. Note, it is the responsibility of the registration binder to
+  // set this properly.
+  int32_t builtin_code;
+} TfLiteRegistration;
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif  // __cplusplus
+#endif  // THIRD_PARTY_TENSORFLOW_CONTRIB_LITE_CONTEXT_H_