Remove modulus operator where possible.

1 files changed, 33 insertions, 9 deletions

diff --git a/GcodeProcessorLib/array_list.h b/GcodeProcessorLib/array_list.h
index 4303fe1..e5aec2e 100644
--- a/GcodeProcessorLib/array_list.h
+++ b/GcodeProcessorLib/array_list.h
@@ -61,6 +61,16 @@ public:
 		items_ = new_items;
 		max_size_ = max_size;
 	}
+
+	inline int get_index_position(int index) const
+	{
+		int index_position = index + front_index_ + max_size_;
+		while (index_position >= max_size_)
+		{
+			index_position = index_position - max_size_;
+		}
+		return index_position;
+	}
 	
 	void push_front(T object)
 	{
@@ -74,7 +84,12 @@ public:
 				throw std::exception();
 			}
 		}
-		front_index_ = (front_index_ - 1 + max_size_) % max_size_;
+		//front_index_ = (front_index_ - 1 + max_size_) % max_size_;
+		front_index_ -= 1;
+		if (front_index_ < 0)
+		{
+			front_index_ = max_size_ - 1;
+		}
 		count_++;
 		items_[front_index_] = object;
 	}
@@ -91,7 +106,8 @@ public:
 				throw std::exception();
 			}
 		}
-		items_[(front_index_ + count_ + max_size_) % max_size_] = object;
+		int pos = get_index_position(count_);
+		items_[pos] = object;
 		count_++;
 	}
 	
@@ -103,7 +119,12 @@ public:
 		}
 
 		int prev_start = front_index_;
-		front_index_ = (front_index_ + 1 + max_size_) % max_size_;
+
+		front_index_ += 1;
+		if (front_index_ >= max_size_)
+		{
+			front_index_ = 0;
+		}
 		count_--;
 		return items_[prev_start];
 	}
@@ -114,18 +135,21 @@ public:
 		{
 			throw std::exception();
 		}
-
-		return items_[--count_];
+		int pos = get_index_position(count_);
+		count_--;
+		return items_[pos];
 	}
-	
-	T& operator[] (const int index) const
+
+	T& operator[] (int index) const
 	{
-		return items_[(front_index_ + index + max_size_) % max_size_];
+		//int opos = get_index_position(index);
+		return items_[get_index_position(index)];
 	}
 
 	T& get(int index) const
 	{
-		return items_[(front_index_ + index + max_size_) % max_size_];
+		int opos = get_index_position(index);
+		return items_[opos];
 	}
 	
 	int count() const