From 00c9cf068c17f41078eb81a61219c0072bb2a287 Mon Sep 17 00:00:00 2001
From: Fatih Cetinkaya <965295+devfacet@users.noreply.github.com>
Date: Sun, 7 Apr 2024 15:21:11 -0400
Subject: [PATCH] Use fixed-size arrays in Neuron functions (#9)

---
 README.md           |  2 --
 include/nn_neuron.h |  6 +++---
 src/nn_neuron.c     | 14 +++-----------
 3 files changed, 6 insertions(+), 16 deletions(-)

diff --git a/README.md b/README.md
index 3379b86..f420e44 100644
--- a/README.md
+++ b/README.md
@@ -29,11 +29,9 @@ git submodule update --init
 ### Build and run examples
 
 ```shell
-# Generic examples
 make build-examples ARCH=generic
 make run-examples ARCH=generic
 
-# Arm examples
 make build-examples ARCH=arm TECH=neon,cmsis-dsp
 make run-examples ARCH=arm TECH=neon,cmsis-dsp
 ```
diff --git a/include/nn_neuron.h b/include/nn_neuron.h
index 007fab7..a29bcd7 100644
--- a/include/nn_neuron.h
+++ b/include/nn_neuron.h
@@ -24,15 +24,15 @@ typedef struct {
 } NNNeuron;
 
 // nn_neuron_init initializes a neuron with the given arguments.
-bool nn_neuron_init(NNNeuron *neuron, const float *weights, size_t n_weights, float bias, NNActivationFunction act_func, NNDotProductFunction dot_product_func, NNError *error);
+bool nn_neuron_init(NNNeuron *neuron, const float weights[NEURON_MAX_WEIGHTS], size_t n_weights, float bias, NNActivationFunction act_func, NNDotProductFunction dot_product_func, NNError *error);
 
 // nn_neuron_set_weights sets the weights of the given neuron.
-bool nn_neuron_set_weights(NNNeuron *neuron, const float *weights, NNError *error);
+bool nn_neuron_set_weights(NNNeuron *neuron, const float weights[NEURON_MAX_WEIGHTS], NNError *error);
 
 // nn_neuron_set_bias sets the bias of the given neuron.
 bool nn_neuron_set_bias(NNNeuron *neuron, float bias, NNError *error);
 
 // nn_neuron_compute computes the given neuron and returns the output.
-float nn_neuron_compute(const NNNeuron *neuron, const float *inputs, NNError *error);
+float nn_neuron_compute(const NNNeuron *neuron, const float inputs[NEURON_MAX_WEIGHTS], NNError *error);
 
 #endif // NN_NEURON_H
diff --git a/src/nn_neuron.c b/src/nn_neuron.c
index 7771f65..d05b4d8 100644
--- a/src/nn_neuron.c
+++ b/src/nn_neuron.c
@@ -7,7 +7,7 @@
 #include <stdio.h>
 
 // nn_neuron_init initializes a neuron with the given arguments.
-bool nn_neuron_init(NNNeuron *neuron, const float *weights, size_t n_weights, float bias, NNActivationFunction act_func, NNDotProductFunction dot_product_func, NNError *error) {
+bool nn_neuron_init(NNNeuron *neuron, const float weights[NEURON_MAX_WEIGHTS], size_t n_weights, float bias, NNActivationFunction act_func, NNDotProductFunction dot_product_func, NNError *error) {
     nn_error_set(error, NN_ERROR_NONE, NULL);
     if (neuron == NULL) {
         nn_error_set(error, NN_ERROR_INVALID_INSTANCE, "neuron is NULL");
@@ -32,16 +32,12 @@ bool nn_neuron_init(NNNeuron *neuron, const float *weights, size_t n_weights, fl
 }
 
 // nn_neuron_set_weights sets the weights of the given neuron.
-bool nn_neuron_set_weights(NNNeuron *neuron, const float *weights, NNError *error) {
+bool nn_neuron_set_weights(NNNeuron *neuron, const float weights[NEURON_MAX_WEIGHTS], NNError *error) {
     nn_error_set(error, NN_ERROR_NONE, NULL);
     if (neuron == NULL) {
         nn_error_set(error, NN_ERROR_INVALID_INSTANCE, "neuron is NULL");
         return false;
     }
-    if (weights == NULL) {
-        nn_error_set(error, NN_ERROR_INVALID_INSTANCE, "weights is NULL");
-        return false;
-    }
     for (size_t i = 0; i < neuron->n_weights; ++i) {
         neuron->weights[i] = weights[i];
     }
@@ -60,16 +56,12 @@ bool nn_neuron_set_bias(NNNeuron *neuron, float bias, NNError *error) {
 }
 
 // nn_neuron_compute computes the given neuron and returns the output.
-float nn_neuron_compute(const NNNeuron *neuron, const float *inputs, NNError *error) {
+float nn_neuron_compute(const NNNeuron *neuron, const float inputs[NEURON_MAX_WEIGHTS], NNError *error) {
     nn_error_set(error, NN_ERROR_NONE, NULL);
     if (neuron == NULL) {
         nn_error_set(error, NN_ERROR_INVALID_INSTANCE, "neuron is NULL");
         return NAN;
     }
-    if (inputs == NULL) {
-        nn_error_set(error, NN_ERROR_INVALID_INSTANCE, "inputs is NULL");
-        return NAN;
-    }
 
     // Initialize the result
     float result = 0.0f;