From 34742a8db667b9ec6f62f366a861afd10a90a256 Mon Sep 17 00:00:00 2001
From: Zhang Ji Peng <onecoolx@gmail.com>
Date: Fri, 26 Jul 2024 17:58:21 +0800
Subject: [PATCH] perf(array): optimize array remove / erase function
 performance (#6544)

Signed-off-by: zhangjipeng <zhangjipeng@xiaomi.com>
Co-authored-by: zhangjipeng <zhangjipeng@xiaomi.com>
---
 src/misc/lv_array.c | 19 +++++++++++++++----
 src/misc/lv_array.h | 10 ++++++++++
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/src/misc/lv_array.c b/src/misc/lv_array.c
index f59cb74a9..5de604b45 100644
--- a/src/misc/lv_array.c
+++ b/src/misc/lv_array.c
@@ -67,6 +67,13 @@ void lv_array_copy(lv_array_t * target, const lv_array_t * source)
     target->size = source->size;
 }
 
+void lv_array_shrink(lv_array_t * array)
+{
+    if(array->size <= array->capacity / LV_ARRAY_DEFAULT_SHRINK_RATIO) {
+        lv_array_resize(array, array->size);
+    }
+}
+
 lv_result_t lv_array_remove(lv_array_t * array, uint32_t index)
 {
     if(index >= array->size) {
@@ -75,7 +82,8 @@ lv_result_t lv_array_remove(lv_array_t * array, uint32_t index)
 
     /*Shortcut*/
     if(index == array->size - 1) {
-        lv_array_resize(array, array->size - 1);
+        array->size--;
+        lv_array_shrink(array);
         return LV_RESULT_OK;
     }
 
@@ -83,7 +91,8 @@ lv_result_t lv_array_remove(lv_array_t * array, uint32_t index)
     uint8_t * remaining = start + array->element_size;
     uint32_t remaining_size = (array->size - index - 1) * array->element_size;
     lv_memmove(start, remaining, remaining_size);
-    lv_array_resize(array, array->size - 1);
+    array->size--;
+    lv_array_shrink(array);
     return LV_RESULT_OK;
 }
 
@@ -99,7 +108,8 @@ lv_result_t lv_array_erase(lv_array_t * array, uint32_t start, uint32_t end)
 
     /*Shortcut*/
     if(end == array->size) {
-        lv_array_resize(array, start);
+        array->size = start;
+        lv_array_shrink(array);
         return LV_RESULT_OK;
     }
 
@@ -107,7 +117,8 @@ lv_result_t lv_array_erase(lv_array_t * array, uint32_t start, uint32_t end)
     uint8_t * remaining = start_p + (end - start) * array->element_size;
     uint32_t remaining_size = (array->size - end) * array->element_size;
     lv_memcpy(start_p, remaining, remaining_size);
-    lv_array_resize(array, array->size - (end - start));
+    array->size -= (end - start);
+    lv_array_shrink(array);
     return LV_RESULT_OK;
 }
 
diff --git a/src/misc/lv_array.h b/src/misc/lv_array.h
index cd0f87c5a..a32490913 100644
--- a/src/misc/lv_array.h
+++ b/src/misc/lv_array.h
@@ -23,6 +23,10 @@ extern "C" {
 #define LV_ARRAY_DEFAULT_CAPACITY  4
 #endif
 
+#ifndef LV_ARRAY_DEFAULT_SHRINK_RATIO
+#define LV_ARRAY_DEFAULT_SHRINK_RATIO 2
+#endif
+
 /**********************
  *      TYPEDEFS
  **********************/
@@ -118,6 +122,12 @@ static inline void lv_array_clear(lv_array_t * array)
     array->size = 0;
 }
 
+/**
+ * Shrink the memory capacity of array if necessary.
+ * @param array pointer to an `lv_array_t` variable
+ */
+void lv_array_shrink(lv_array_t * array);
+
 /**
  * Remove the element at the specified position in the array.
  * @param array pointer to an `lv_array_t` variable