fix issue with null send to asm function

main.c

@@ -77,12 +77,20 @@ test_strcpy() {
 	{
 		printf("ft_strcpy:\n");
 
+		ft_strcpy(NULL, NULL);
+
 		char src_empty[] = "";
 		char dst_empty[] = "";
 		char *ret = ft_strcpy(dst_empty, src_empty);
 		printf ("ret: %s_%p, src: %s_%p, dest: %s_%p\n",
 				ret, ret, src_empty, src_empty, dst_empty, dst_empty);
 
+		char null_char[0];
+		ft_strcpy(null_char, NULL);
+
+		ft_strcpy(dst_empty, NULL);
+		ft_strcpy(NULL, src_empty);
+
 		char src[10] = "src";
 		char dst[10] = "dst";
 		printf ("src: %s, dest: %s\n", src, dst);

src/ft_strcpy.s

@@ -9,6 +9,11 @@ section .text
 		mov rax, 0 ; counter
 		mov rdx, 0
 
+		cmp rdi, 0
+		je endloop 
+		cmp rsi, 0
+		je endloop 
+
 		loop:
 			mov dl, [rsi + rax] ; get char from src
 			mov [rdi + rax], dl ; replace char by char
@@ -17,6 +22,7 @@ section .text
 
 			cmp dl, 0
 			jne loop
+		endloop:
 
 		mov rax, rdi
 		ret