1 files changed, 74 insertions, 0 deletions
diff --git a/newlib/libc/machine/i386/memmove.S b/newlib/libc/machine/i386/memmove.S
new file mode 100644
index 0000000..e1aca0d
--- /dev/null
+++ b/newlib/libc/machine/i386/memmove.S
@@ -0,0 +1,74 @@
+/*
+ * ====================================================
+ * Copyright (C) 1998 by Cygnus Solutions. All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+	#include "i386mach.h"
+	
+	.global SYM (memmove)
+
+SYM (memmove):
+
+	pushl ebp
+	movl esp,ebp
+	pushl esi
+	pushl edi
+	pushl ebx
+	movl 8(ebp),edi
+	movl 16(ebp),ecx
+	movl 12(ebp),esi
+
+/*  check for destructive overlap (src < dst && dst < src + length) */
+	
+	cld
+	cmpl edi,esi
+	jae  .L2
+	leal -1(ecx,esi),ebx
+	cmpl ebx,edi
+	ja   .L2
+
+/* destructive overlap, must copy backwards...do it a byte at a time since it is uncommon */	
+
+	decl edi
+	movl ebx,esi
+	addl ecx,edi
+	std
+	jmp BYTEMOVE
+.L2:
+#ifndef __OPTIMIZE_SIZE__
+/* non-destructive overlap so we can try and move 4 bytes at a time */
+			
+	movl esi,eax
+	orl edi,eax
+	testb $3,al
+	jne BYTEMOVE
+	shrl $2,ecx
+	rep
+	movsl
+
+/* calculate any remainder bytes after moving doublewords */
+
+	movl 16(ebp),ecx
+	andl $3,ecx
+
+#endif /* not __OPTIMIZE_SIZE__ */
+	
+/* move any unaligned bytes or remainder bytes, one at a time */
+
+BYTEMOVE: 
+	rep
+	movsb
+		
+	movl 8(ebp),eax
+
+	leal -12(ebp),esp
+	popl ebx
+	popl edi
+	popl esi
+	leave
+	ret