.gitignore

@@ -1,3 +0,0 @@
-*.o
-a.out
-build

alloca.S

@@ -1,4 +1,8 @@
-.include "lib/alloca.S"
+.intel_syntax noprefix
+
+.macro  alloca size
+sub rsp, \size
+.endm
 
 .text
 

lib/alloca.S

@@ -1,5 +0,0 @@
-.intel_syntax noprefix
-
-.macro  alloca size
-sub rsp, \size
-.endm

lib/strcpy.S

@@ -1,17 +0,0 @@
-    .intel_syntax noprefix
-
-    .text
-
-# String-copying routine. Strings should be null-terminated.
-# Input: rdi = source string base, rsi = destination string base
-# No check is done for buffer overflow.
-strcpy:
-    movb r10b, [rdi]
-    cmpb r10b, 0
-    je .end
-    movb [rsi], r10b
-    inc rdi
-    inc rsi
-    jmp strcpy
-.end:
-    ret

strcpy.S

@@ -1,5 +1,3 @@
-    .include "lib/strcpy.S"
-
     .intel_syntax noprefix
 
     .globl _start
@@ -7,6 +5,22 @@
     .text
 
 
+# String-copying routine.
+# Commented-out lines would also return the starting address of the destination address.
+strcpy:
+#    push rsi
+.loop:
+    movb r10b, [rdi]
+    cmpb r10b, 0
+    je .end
+    movb [rsi], r10b
+    inc rdi
+    inc rsi
+    jmp .loop
+.end:
+#    pop rax
+    ret
+
 _start:
 
     mov rdi, offset str2