Add float and hybrid tests for LSTM (#1092)

* Add float tests for LSTM

* Format test code properly

* Zero state and output buffers

* Add test for batch major input/ouput

* Add hybrid tests

* RISC-V build fails on std::round(), replace with round()

* Minor formatting changes suggested by comments

* Refactor tests to use test config structs

* Remove unused const variable

* Put test config data into separate source/header files

* Add bazel build file

tensorflow/lite/micro/kernels/BUILD

@@ -332,6 +332,13 @@ cc_library(
     hdrs = ["micro_utils.h"],
 )
 
+cc_library(
+    name = "unidirectional_sequence_lstm_test_config",
+    srcs = ["unidirectional_sequence_lstm_test_config.cc"],
+    hdrs = ["unidirectional_sequence_lstm_test_config.h"],
+    deps = ["//tensorflow/lite/c:common"],
+)
+
 ####################################
 # C++ tests
 ####################################
@@ -1293,6 +1300,7 @@ cc_test(
         "//tensorflow/lite/micro:micro_utils",
         "//tensorflow/lite/micro:op_resolvers",
         "//tensorflow/lite/micro:test_helpers",
+        "//tensorflow/lite/micro/kernels:unidirectional_sequence_lstm_test_config",
         "//tensorflow/lite/micro/testing:micro_test",
     ],
 )

tensorflow/lite/micro/kernels/Makefile.inc

@@ -38,6 +38,11 @@ $(eval $(call microlite_test,kernel_transpose_conv_test,\
   tensorflow/lite/micro/kernels/conv_test_common.cc,\
   tensorflow/lite/micro/kernels/conv_test.h))
 
+$(eval $(call microlite_test,unidirectional_sequence_lstm_test,\
+  tensorflow/lite/micro/kernels/unidirectional_sequence_lstm_test.cc \
+  tensorflow/lite/micro/kernels/unidirectional_sequence_lstm_test_config.cc,\
+  tensorflow/lite/micro/kernels/unidirectional_sequence_lstm_test_config.h))
+
 # For kernel tests without extra dependencies (beyond libtensorflow-microlite.a),
 # use simple for loop to generate their make targets in a common way.
 MICROLITE_KERNEL_SIMPLE_TEST_SRCS := \
@@ -103,7 +108,6 @@ tensorflow/lite/micro/kernels/sub_test.cc \
 tensorflow/lite/micro/kernels/svdf_test.cc \
 tensorflow/lite/micro/kernels/tanh_test.cc \
 tensorflow/lite/micro/kernels/transpose_test.cc \
-tensorflow/lite/micro/kernels/unidirectional_sequence_lstm_test.cc \
 tensorflow/lite/micro/kernels/unpack_test.cc \
 tensorflow/lite/micro/kernels/while_test.cc \
 tensorflow/lite/micro/kernels/zeros_like_test.cc