llvm-for-llvmta/include/llvm/Analysis/Utils/TFUtils.h

267 lines
10 KiB
C++

//===- TFUtils.h - utilities for tensorflow C API ---------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
#ifndef LLVM_ANALYSIS_UTILS_TFUTILS_H
#define LLVM_ANALYSIS_UTILS_TFUTILS_H
#include "llvm/Config/llvm-config.h"
#ifdef LLVM_HAVE_TF_API
#include "llvm/IR/LLVMContext.h"
#include "llvm/Support/JSON.h"
#include <memory>
#include <vector>
namespace llvm {
/// Load a SavedModel, find the given inputs and outputs, and setup storage
/// for input tensors. The user is responsible for correctly dimensioning the
/// input tensors and setting their values before calling evaluate().
/// To initialize:
/// - construct the object
/// - initialize the input tensors using initInput. Indices must correspond to
/// indices in the InputNames used at construction.
/// To use:
/// - set input values by using getInput to get each input tensor, and then
/// setting internal scalars, for all dimensions (tensors are row-major:
/// https://github.com/tensorflow/tensorflow/blob/r1.5/tensorflow/c/c_api.h#L205)
/// - call evaluate. The input tensors' values are not consumed after this, and
/// may still be read.
/// - use the outputs in the output vector
class TFModelEvaluatorImpl;
class EvaluationResultImpl;
/// TensorSpec encapsulates the specification of a tensor: its dimensions, or
/// "shape" (row-major), its type (see TensorSpec::getDataType specializations
/// for supported types), its name and port (see "TensorFlow: Large-Scale
/// Machine Learning on Heterogeneous Distributed Systems", section 4.2, para 2:
/// https://static.googleusercontent.com/media/research.google.com/en//pubs/archive/45166.pdf)
///
/// TensorSpec is used to set up a TFModelEvaluator by describing the expected
/// inputs and outputs.
class TensorSpec final {
public:
template <typename T>
static TensorSpec createSpec(const std::string &Name,
const std::vector<int64_t> &Shape,
int Port = 0) {
return TensorSpec(Name, Port, getDataType<T>(), Shape);
}
const std::string &name() const { return Name; }
int port() const { return Port; }
int typeIndex() const { return TypeIndex; }
const std::vector<int64_t> &shape() const { return Shape; }
bool operator==(const TensorSpec &Other) const {
return Name == Other.Name && Port == Other.Port &&
TypeIndex == Other.TypeIndex && Shape == Other.Shape;
}
bool operator!=(const TensorSpec &Other) const { return !(*this == Other); }
/// Get the number of elements in a tensor with this shape.
size_t getElementCount() const { return ElementCount; }
/// Get the size, in bytes, of one element.
size_t getElementByteSize() const;
template <typename T> bool isElementType() const {
return getDataType<T>() == TypeIndex;
}
private:
TensorSpec(const std::string &Name, int Port, int TypeIndex,
const std::vector<int64_t> &Shape);
template <typename T> static int getDataType() {
llvm_unreachable("Undefined tensor type");
}
std::string Name;
int Port = 0;
int TypeIndex = 0;
std::vector<int64_t> Shape;
size_t ElementCount = 0;
};
/// Construct a TensorSpec from a JSON dictionary of the form:
/// { "name": <string>,
/// "port": <int>,
/// "type": <string. Use LLVM's types, e.g. float, double, int64_t>,
/// "shape": <array of ints> }
/// For the "type" field, see the C++ primitive types used in
/// TFUTILS_SUPPORTED_TYPES.
Optional<TensorSpec> getTensorSpecFromJSON(LLVMContext &Ctx,
const json::Value &Value);
struct LoggedFeatureSpec {
TensorSpec Spec;
Optional<std::string> LoggingName;
};
/// Load the output specs. If SpecFileOverride is not empty, that path is used.
/// Otherwise, the file is assumed to be called 'output_spec.json' and be found
/// under ModelPath (the model directory).
/// The first output tensor name must match ExpectedDecisionName.
/// In case of error, the return is None and the error is logged.
Optional<std::vector<LoggedFeatureSpec>>
loadOutputSpecs(LLVMContext &Ctx, StringRef ExpectedDecisionName,
StringRef ModelPath, StringRef SpecFileOverride = StringRef());
/// Logging utility - given an ordered specification of features, and assuming
/// a scalar reward, allow logging feature values and rewards, and then print
/// as tf.train.SequenceExample text protobuf.
/// The assumption is that, for an event to be logged (i.e. a set of feature
/// values and a reward), the user calls the log* API for each feature exactly
/// once, providing the index matching the position in the feature spec list
/// provided at construction:
/// event 0:
/// logTensorValue(0, ...)
/// logTensorValue(1, ...)
/// ...
/// logReward(...)
/// event 1:
/// logTensorValue(0, ...)
/// logTensorValue(1, ...)
/// ...
/// logReward(...)
///
/// At the end, call print to generate the protobuf.
class Logger final {
public:
/// Construct a Logger. If IncludeReward is false, then logReward shouldn't
/// be called, and the reward feature won't be printed out.
Logger(const std::vector<LoggedFeatureSpec> &FeatureSpecs,
const TensorSpec &RewardSpec, bool IncludeReward)
: FeatureSpecs(FeatureSpecs), RewardSpec(RewardSpec),
RawLogData(FeatureSpecs.size() + IncludeReward),
IncludeReward(IncludeReward) {}
template <typename T> void logReward(T Value) {
assert(IncludeReward);
logTensorValue(RawLogData.size() - 1, &Value);
}
template <typename T> void logFinalReward(T Value) {
assert(RawLogData.back().empty());
logReward(Value);
}
template <typename T>
void logTensorValue(size_t FeatureID, const T *Value, size_t Size = 1) {
const char *Start = reinterpret_cast<const char *>(Value);
const char *End = Start + sizeof(T) * Size;
RawLogData[FeatureID].insert(RawLogData[FeatureID].end(), Start, End);
}
void print(raw_ostream &OS);
private:
std::vector<LoggedFeatureSpec> FeatureSpecs;
TensorSpec RewardSpec;
/// RawData has one entry per feature, plus one more for the reward.
/// Each feature's values are then stored in a vector, in succession.
/// This means the ith event is stored at [*][i]
std::vector<std::vector<char>> RawLogData;
const bool IncludeReward;
};
class TFModelEvaluator final {
public:
/// The result of a model evaluation. Handles the lifetime of the output
/// tensors, which means that their values need to be used before
/// the EvaluationResult's dtor is called.
class EvaluationResult {
public:
EvaluationResult(const EvaluationResult &) = delete;
EvaluationResult &operator=(const EvaluationResult &Other) = delete;
EvaluationResult(EvaluationResult &&Other);
EvaluationResult &operator=(EvaluationResult &&Other);
~EvaluationResult();
/// Get a (const) pointer to the first element of the tensor at Index.
template <typename T> T *getTensorValue(size_t Index) {
return static_cast<T *>(getUntypedTensorValue(Index));
}
template <typename T> const T *getTensorValue(size_t Index) const {
return static_cast<T *>(getUntypedTensorValue(Index));
}
/// Get a (const) pointer to the untyped data of the tensor.
void *getUntypedTensorValue(size_t Index);
const void *getUntypedTensorValue(size_t Index) const;
private:
friend class TFModelEvaluator;
EvaluationResult(std::unique_ptr<EvaluationResultImpl> Impl);
std::unique_ptr<EvaluationResultImpl> Impl;
};
TFModelEvaluator(StringRef SavedModelPath,
const std::vector<TensorSpec> &InputSpecs,
const std::vector<TensorSpec> &OutputSpecs,
const char *Tags = "serve");
TFModelEvaluator(StringRef SavedModelPath,
const std::vector<TensorSpec> &InputSpecs,
function_ref<TensorSpec(size_t)> GetOutputSpecs,
size_t OutputSpecsSize, const char *Tags = "serve");
~TFModelEvaluator();
TFModelEvaluator(const TFModelEvaluator &) = delete;
TFModelEvaluator(TFModelEvaluator &&) = delete;
/// Evaluate the model, assuming it is valid. Returns None if the evaluation
/// fails or the model is invalid, or an EvaluationResult otherwise. The
/// inputs are assumed to have been already provided via getInput(). When
/// returning None, it also invalidates this object.
Optional<EvaluationResult> evaluate();
/// Provides access to the input vector.
template <typename T> T *getInput(size_t Index) {
return static_cast<T *>(getUntypedInput(Index));
}
/// Returns true if the tensorflow model was loaded successfully, false
/// otherwise.
bool isValid() const { return !!Impl; }
private:
void *getUntypedInput(size_t Index);
std::unique_ptr<TFModelEvaluatorImpl> Impl;
};
/// List of supported types, as a pair:
/// - C++ type
/// - enum name (implementation-specific)
#define TFUTILS_SUPPORTED_TYPES(M) \
M(float, TF_FLOAT) \
M(double, TF_DOUBLE) \
M(int8_t, TF_INT8) \
M(uint8_t, TF_UINT8) \
M(int16_t, TF_INT16) \
M(uint16_t, TF_UINT16) \
M(int32_t, TF_INT32) \
M(uint32_t, TF_UINT32) \
M(int64_t, TF_INT64) \
M(uint64_t, TF_UINT64)
#define TFUTILS_GETDATATYPE_DEF(T, E) \
template <> int TensorSpec::getDataType<T>();
TFUTILS_SUPPORTED_TYPES(TFUTILS_GETDATATYPE_DEF)
#undef TFUTILS_GETDATATYPE_DEF
} // namespace llvm
#endif // LLVM_HAVE_TF_API
#endif // LLVM_ANALYSIS_UTILS_TFUTILS_H