1 files changed, 78 insertions, 0 deletions
diff --git a/compiler/luci-interpreter/pal/cmsisnn/PALSoftmax.h b/compiler/luci-interpreter/pal/cmsisnn/PALSoftmax.h
new file mode 100644
index 000000000..6bbda4867
--- /dev/null
+++ b/compiler/luci-interpreter/pal/cmsisnn/PALSoftmax.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2021 Samsung Electronics Co., Ltd. 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.
+ */
+
+#ifndef LUCI_INTERPRETER_PAL_SOFTMAX_H
+#define LUCI_INTERPRETER_PAL_SOFTMAX_H
+
+#include <tensorflow/lite/kernels/internal/reference/softmax.h>
+#include <arm_nnfunctions.h>
+
+namespace luci_interpreter_pal
+{
+static inline void PopulateSoftmaxLookupTable(tflite::SoftmaxParams *data, float input_scale,
+                                              float beta)
+{
+  // Do nothing for mcu
+  (void)data;
+  (void)input_scale;
+  (void)beta;
+}
+
+static inline void InitializeParams(tflite::SoftmaxParams *params, float input_scale, float beta)
+{
+  int32 input_beta_multiplier;
+  int input_beta_left_shift;
+  static const int kScaledDiffIntegerBits = 5;
+  tflite::PreprocessSoftmaxScaling(beta, input_scale, kScaledDiffIntegerBits,
+                                   &input_beta_multiplier, &input_beta_left_shift);
+
+  params->input_multiplier = input_beta_multiplier;
+  params->input_left_shift = input_beta_left_shift;
+  params->diff_min =
+    -tflite::CalculateInputRadius(kScaledDiffIntegerBits, params->input_left_shift);
+}
+
+template <typename T>
+static inline void Softmax(const tflite::SoftmaxParams &params,
+                           const tflite::RuntimeShape &input_shape, const T *input_data,
+                           const tflite::RuntimeShape &output_shape, T *output_data)
+{
+  // MARK: At this moment this operation doesn't support on mcu
+  assert(false && "Softmax NYI");
+  (void)params;
+  (void)input_shape;
+  (void)input_data;
+  (void)output_shape;
+  (void)output_data;
+}
+
+template <>
+inline void Softmax<int8_t>(const tflite::SoftmaxParams &params,
+                            const tflite::RuntimeShape &input_shape, const int8_t *input_data,
+                            const tflite::RuntimeShape &output_shape, int8_t *output_data)
+{
+  const int trailing_dim = input_shape.DimensionsCount() - 1;
+  const int outer_size = tflite::MatchingFlatSizeSkipDim(input_shape, trailing_dim, output_shape);
+  const int depth = tflite::MatchingDim(input_shape, trailing_dim, output_shape, trailing_dim);
+  const int32_t mult = params.input_multiplier;
+  const int32_t shift = params.input_left_shift;
+  const int32_t diff_min = params.diff_min;
+
+  arm_softmax_s8(input_data, outer_size, depth, mult, shift, diff_min, output_data);
+}
+} // namespace luci_interpreter_pal
+
+#endif // LUCI_INTERPRETER_PAL_SOFTMAX_H