diff --git a/kitty/data-types.h b/kitty/data-types.h
index e322ca2cf..d8108780e 100644
--- a/kitty/data-types.h
+++ b/kitty/data-types.h
@@ -427,3 +427,13 @@ SPRITE_MAP_HANDLE alloc_sprite_map(unsigned int, unsigned int);
 SPRITE_MAP_HANDLE free_sprite_map(SPRITE_MAP_HANDLE);
 const char* get_hyperlink_for_id(const HYPERLINK_POOL_HANDLE, hyperlink_id_type id, bool only_url);
 void log_event(const char *format, ...) __attribute__((format(printf, 1, 2)));
+
+#define memset_array(array, val, count) if ((count) > 0) { \
+    (array)[0] = (val); \
+    size_t __copied__ = 1; \
+    while (__copied__ < (count)) { \
+        const size_t __num__ = MIN(__copied__, (count) - __copied__); \
+        memcpy((array) + __copied__, (array), __num__ * sizeof((val))); \
+        __copied__ += __num__; \
+    } \
+}
diff --git a/kitty/line-buf.c b/kitty/line-buf.c
index 4aeb08482..42b30d991 100644
--- a/kitty/line-buf.c
+++ b/kitty/line-buf.c
@@ -154,7 +154,7 @@ linebuf_clear_lines(LineBuf *self, const Cursor *cursor, index_type start, index
 #define lineptr(which, i) which##_lineptr(self, self->line_map[i])
     GPUCell *first_gpu_line = lineptr(gpu, start);
     const GPUCell gc = cursor_as_gpu_cell(cursor);
-    for (index_type i = 0; i < self->xnum; i++) memcpy(first_gpu_line + i, &gc, sizeof(GPUCell));
+    memset_array(first_gpu_line, gc, self->xnum);
     const size_t cpu_stride = sizeof(CPUCell) * self->xnum;
     memset(lineptr(cpu, start), 0, cpu_stride);
     const size_t gpu_stride = sizeof(GPUCell) * self->xnum;
diff --git a/kitty/line.c b/kitty/line.c
index 09f9cdaaa..229221911 100644
--- a/kitty/line.c
+++ b/kitty/line.c
@@ -521,11 +521,10 @@ cursor_from(Line* self, PyObject *args) {
 void
 line_clear_text(Line *self, unsigned int at, unsigned int num, char_type ch) {
     const uint16_t width = ch ? 1 : 0;
-    for (index_type i = at; i < MIN(self->xnum, at + num); i++) {
-        self->cpu_cells[i].ch = ch; memset(self->cpu_cells[i].cc_idx, 0, sizeof(self->cpu_cells[i].cc_idx));
-        self->cpu_cells[i].hyperlink_id = 0;
-        self->gpu_cells[i].attrs.width = width;
-    }
+    const CPUCell cc = {.ch=ch};
+    if (at + num > self->xnum) num = self->xnum > at ? self->xnum - at : 0;
+    memset_array(self->cpu_cells + at, cc, num);
+    for (index_type i = at; i < at + num; i++) self->gpu_cells[i].attrs.width = width;
 }
 
 static PyObject*
@@ -545,10 +544,9 @@ line_apply_cursor(Line *self, const Cursor *cursor, unsigned int at, unsigned in
 #if BLANK_CHAR != 0
 #error This implementation is incorrect for BLANK_CHAR != 0
 #endif
-        for (index_type i = at; i < self->xnum && i < at + num; i++) {
-            memset(self->cpu_cells + i, 0, sizeof(self->cpu_cells[0]));
-            memcpy(self->gpu_cells + i, &gc, sizeof(gc));
-        }
+        if (at + num > self->xnum) { num = at < self->xnum ? self->xnum - at : 0; }
+        memset(self->cpu_cells + at, 0, num * sizeof(CPUCell));
+        memset_array(self->gpu_cells + at, gc, num);
     } else {
         for (index_type i = at; i < self->xnum && i < at + num; i++) {
             gc.attrs.width = self->gpu_cells[i].attrs.width;