* Add a new test case for conv operator (#329)

This new test case is based on issue #329 to increase
coverage on optimized kernel's data precision for conv operator.
In this test, input, output and filter are all 8 bits and filter
tensor is of dimension 8x3x3x3 with different scales per output channel.

TESTED= local test with x86 and HiFi4.

* Move large test data variable into its own folder
and use one flat top namespace instead of nested namespace.

BUG=195779890

* Add files from TfLite

Added batch_matmul.h and tensor_utils_common.h that are needed for the BATCH_MATMUL operator.

* Arduino library creation for CI build.
Issue# 256

* fix bug with include file path flattening

* fix examples path generation

Some files in examples source and headers list are not in the examples directory.  They can be tensorflow files or third-party files.  The code is corrected so that these files end up inside the generated directory tree.  Previously, these files were being placed outside the generated directory tree and were thus invisible to follow-on targeted generation scripts.

* remove/revert files that go into the arduino-examples repo

* Format with:

```
tensorflow/lite/micro/tools/ci_build/test_code_style.sh --fix_formatting
```

* request changes to PR

* Removed symbolic link for micro_speech example from Makefile.
Added additional include flags to Makefile.
Adjusted header file transformations during base tree creation.

* Fix formatting.

* Move Arduino specific code to seperate repo

Remove ARDUINO defines.
Fix incorrect NDEBUG use.

Issue  #256

* Fix cortex_m_generic makefile

Fix typo in cortex_m_generic makefile so that the correct list of header files is generated by the create_tflm_tree.py script.

bug=Arduino library creation external to the tflite-micro repository #256
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>
Co-authored-by: NAdvait Jain <advaitjain@google.com>

* Fix typo in test_code_style.sh

* Format python code.

* Reset code style.

* Add files from TfLite

Added batch_matmul.h and tensor_utils_common.h that are needed for the BATCH_MATMUL operator.

* Arduino library creation for CI build.
Issue# 256

* fix bug with include file path flattening

* fix examples path generation

Some files in examples source and headers list are not in the examples directory.  They can be tensorflow files or third-party files.  The code is corrected so that these files end up inside the generated directory tree.  Previously, these files were being placed outside the generated directory tree and were thus invisible to follow-on targeted generation scripts.

* remove/revert files that go into the arduino-examples repo

* Format with:

```
tensorflow/lite/micro/tools/ci_build/test_code_style.sh --fix_formatting
```

* request changes to PR

* Removed symbolic link for micro_speech example from Makefile.
Added additional include flags to Makefile.
Adjusted header file transformations during base tree creation.
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>
Co-authored-by: NAdvait Jain <advaitjain@google.com>

* REF_CODE_REFACTOR: hard_swish
Refactoring the reference code for hard_swish operator.

BUG=refactoring existing code.

* Remove uint8 support.

* fix formatting.
Co-authored-by: NAdvait Jain <advaitjain@google.com>

* REF_CODE_REFACTOR: logicalAND and logicalOR
Refactoring the reference code for logicalAND and logicalOR operators.

BUG=refactoring existing code.

* Fix formatting.

* fix bad merge (copyright year).
Co-authored-by: NAdvait Jain <advaitjain@google.com>
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>

* Fixes for RISCV build

* Consolidate compiler flags

* Added RISC-V continuous integration script
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>

* REF_CODE_REFACTOR: logistic
Refactoring the reference code for logistic operator.

BUG=refactoring existing code.

* Fix formatting
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>
Co-authored-by: NAdvait Jain <advaitjain@google.com>

Updated the script to download HiFi 4 Neural Network Library v2.4.1.
Removed the hifi4 patch
Updates in v2.4.1 library:
+ Fixed the issue related to special case handling in xa_nn_dot_prod_16x16_asym8s.
  Moved the special cases handling for vec_length=8/32 to the start of the function.
+ Removed legacy condition checks for depthwise_conv kernels.
+ Fixed the non-bit-exact issue related to xa_nn_conv2d_std_per_chan_sym8sxasym8s.
  updated to select correct vec values in case of vec_align_val is 1 and

* REF_CODE_REFACTOR: activations.cc

Refactoring the reference code for activations operators.

BUG=refactoring existing code.

* Remove uint8 support.

* Ran `test_code_style.sh --fix_formatting`

* Fix the build.
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>
Co-authored-by: NAdvait Jain <advaitjain@google.com>

* Fixes for RISCV build

* Consolidate compiler flags

With http://cl/386537127 (tensorflow/tensorflow@d4987a9) we do not run into the type-limits warning and -Wno-type-limits can be removed.

BUG=http://b/194523886

Fixes #294

Copy from xtensa ci scripts to run the test script inside of a docker
container.

We use the espressif/idf:release-v4.3 image.

Add a build that builds the full tensorflow-microlite.a library.

The person detection example is more complicated and not fixed here.
Co-authored-by: NMichael O'Cleirigh <michael.ocleirigh@gmail.com>
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>

* Groundwork to enable python format checks (via yapf) as part of the CI.

With this change:
 * we are set up to use yapf as part of the docker container
 * pigweed patch is updated to use the google Python style (pep8 with indent of 2 spaces)
 * some documentation updates.

The code still needs to be formatted, and then the Python formatting check will be turned on as part of ci.

BUG=http://b/194404216

* Format all the code.

Once this change is merged, we will turn on Python formatting check as
part of the CI.

* minor formatting update.

* Turn on Python formatting checks as part of CI.

Also, add an option to fix the formatting via the test_code_style.sh
script.

BUG=http://b/194404984 and http://b/194404216

* Groundwork to enable python format checks (via yapf) as part of the CI.

With this change:
 * we are set up to use yapf as part of the docker container
 * pigweed patch is updated to use the google Python style (pep8 with indent of 2 spaces)
 * some documentation updates.

The code still needs to be formatted, and then the Python formatting check will be turned on as part of ci.

BUG=http://b/194404216

* Format all the code.

Once this change is merged, we will turn on Python formatting check as
part of the CI.

* minor formatting update.

With this change:
 * we are set up to use yapf as part of the docker container
 * pigweed patch is updated to use the google Python style (pep8 with indent of 2 spaces)
 * some documentation updates.

The code still needs to be formatted, and then the Python formatting check will be turned on as part of ci.

BUG=http://b/194404216

* Remove distinction between fusion_f1 and hifi4.

Hifi4, Fusion F1 and Hifi3Z all use the same underlying xannlib hifi4
optimizations and with this change we can specify TARGET_ARCH=hifi4 for
each of these cores.

BUG=http://b/194225949

* Fix the build

* Cadence HiFi 5 Neural Network Library v1.6.0
updated the download script to use hifi5 v1.6.0 archive.
depthwise_conv kernel is updated and patch is not required now.
quantize optimized kernel is renamed in the v1.6.0, updated with new
kernel name.

* Fix formatting.
Co-authored-by: Nbhanu prakash bandaru venkata <bhanup@cadence.com>
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>
Co-authored-by: NAdvait Jain <advaitjain@google.com>

BUG=http://b/193437031

* XTENSA_CODE_REFACTOR: depthwise_conv
Refactored the xtensa hifi optimized code for depthwise_conv operator.

* Small fixes for the CI.
Co-authored-by: Nbhanu prakash bandaru venkata <bhanup@cadence.com>
Co-authored-by: NAdvait Jain <advaitjain@google.com>

* Force FLATBUFFERS_LOCALE_INDEPENDENT=0

With this change, we no longer need a #define in the sources that
directly or indrectly include flatbuffers/base.h

BUG=http://b/193264978

* Fix xtensa script.

- Save ~4KB of RAM by implementing a lightweight version of the vector, which only accesses integer values, without implicit conversion.
- Change Micro kernels to access flexbuffers as vectors instead of maps, which is recommended by the flexbuffers doc for efficiency. Since the values in the vector are ordered alphabetically by their keys, the kernels can access them by index instead.
- Revert detection_postprocess to the native flexbuffers API. The
LiteVector API doesn't support IsNull() and I prefer not to support two
custom flexbuffer APIs.
Co-authored-by: NNat Jeffries <natmjeffries@gmail.com>

* Remove MICROLITE_CC_KERNELS_SRCS from the MICROLITE_CC_SRCS list.

Stop the kernel sources from being compiled into both the core
objects and kernel objects.

* Add kernel sources to list_library_sources

* Fix project generation presubmit
Co-authored-by: NNat Jeffries <natmjeffries@gmail.com>

Change-Id: I23e7425445fd8fdb37be0ebb43cb9c8529ceb368
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>

Previously, some sources were built before THIRD_PARTY_TARGETS was downloaded, meaning dependencies in those sources on flatbuffers, gemmlowp, etc could be missed. An alternative to this "dependency for every source" approach could be to add $(THIRD_PARTY_TARGETS) as the first dependency in $(MICROLITE_LIB_PATH), but this relies on Make dependency ordering which is ill-advised

Background: https://stackoverflow.com/questions/9159960/order-of-processing-components-in-makefile

The TFLM Makefile itself ensures that OPTIMIZED_KERNEL_DIR is a valid
path. However, for some special cases (such as http://cl/379964344), we
would like to allow the specialization to gracefully handle a directory
that does not exist in the tree.

BUG=see use-case from http://cl/379964344

- Add external lib references to Hexagon FFT functions

* share code with the cmsis implementation
 * groundwork needed to add in Xtensa implementation

BUG=https://github.com/tensorflow/tflite-micro/issues/205

* Remove lite-specific code from copy of SPACE_TO_DEPTH

Remove the bulk of lite-specific code from the micro
implementation of operator SPACE_TO_DEPTH.

-  Flatten namespace
-  Don't resize output tensors
-  Remove type other than int8 and float32
-  Don't use gtest

* Port operator SPACE_TO_DEPTH from lite

Port the SPACE_TO_DEPTH operator from lite to micro. Add the
operator and test to the build.
Co-authored-by: NPete Warden <pete@petewarden.com>

* Update ethosu driver entrypoint

* Update copyright notice
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>

Overrides core optimization level from -Os to -O2.

* Explicitly build all targets with bazel as part of CI.

With #194 we removed the build_test targets. We are instead going to
explicitly have a bazel build command as part of the CI checks.

* fix typo

* Put location variables before target .inc's are included

They can be useful in the target .inc

Change-Id: I0ee3f77f79be272f4dc3502fb4a38017d8162fa1

* Add ARMC6 compiler support for Corstone-300 target

  * Use fromelf instead of objcopy for armclang toolchain when
    generating a binary
  * Add ARMC6 linker and build flags to the Corstone-330 target
  * Add RETARGET macro in patch script to avoid undefined symbol
    build error for ARMC6.
  * Use a reduced set of Cortex-M CPU's for easier maintenance.

Change-Id: Id9a20d57fa4fa0f1339f44523417e2dabfe7e152

* Review comment - Override exit symbol only for GCC

Change-Id: I93628c92ee352f36c7e7dd99351e4a73c29a8d30

* Review comment - Change how to pass linker options for ARMC6

Change-Id: Iacec5a6df6902bc8a14f460d63ae917039f982cc

* Review comment - correct the upmerge

Change-Id: I9a250f6a444336f9b95428a126a94a18f40060dc
Co-authored-by: NAdvait Jain <advaitjain@users.noreply.github.com>

For the Xtensa docker container, we were getting an error message along the lines of python not found. And the result was that the specialization was happening incorrectly (i.e. the specialization for the kernels was failing since it relies on python since #160).

#182 is likely the reason why this error passed the CI for #160 but started failing after.

* Add third_party/hexagon to include path for hexagon builds.

* Add TODO and change include to kernels/hexagon/inc.