[PATCH][Testsuite]Use user defined memmove in gcc.c-torture/execute/builtins/memops-asm-lib.c

After the change r249278. bcopy is folded into memmove. And in newlib
aarch64 memmove implementation, it will call memcpy in certain conditions.
The memcpy defined in memops-asm-lib.c will abort when the test is running.

A user defined memmove function is defined to bypass the library one.
So that memcpy won't be called accidentally.

gcc/testsuite/

	* gcc.c-torture/execute/builtins/memops-asm-lib.c (my_memmove): New.
	* gcc.c-torture/execute/builtins/memops-asm.c (memmove): Declare memmove.


Co-Authored-By: Szabolcs Nagy <szabolcs.nagy@arm.com>

From-SVN: r249647

gcc/testsuite/ChangeLog

+2017-06-26  Renlin Li  <renlin.li@arm.com>
+	    Szabolcs Nagy  <szabolcs.nagy@arm.com>
+
+	* gcc.c-torture/execute/builtins/memops-asm-lib.c (my_memmove): New.
+	* gcc.c-torture/execute/builtins/memops-asm.c (memmove): Declare
+	memmove.
+
 2017-06-26  Richard Biener  <rguenther@suse.de>
 
 	PR target/81175

gcc/testsuite/gcc.c-torture/execute/builtins/memops-asm-lib.c

@@ -37,6 +37,24 @@ my_bcopy (const void *s, void *d, size_t n)
     }
 }
 
+__attribute__ ((used))
+void
+my_memmove (void *d, const void *s, size_t n)
+{
+  char *dst = (char *) d;
+  const char *src = (const char *) s;
+  if (src >= dst)
+    while (n--)
+      *dst++ = *src++;
+  else
+    {
+      dst += n;
+      src += n;
+      while (n--)
+	*--dst = *--src;
+    }
+}
+
 /* LTO code is at the present to able to track that asm alias my_bcopy on builtin
    actually refers to this function.  See PR47181. */
 __attribute__ ((used))

gcc/testsuite/gcc.c-torture/execute/builtins/memops-asm.c

@@ -12,6 +12,8 @@ extern void *memcpy (void *, const void *, size_t)
   __asm (ASMNAME ("my_memcpy"));
 extern void bcopy (const void *, void *, size_t)
   __asm (ASMNAME ("my_bcopy"));
+extern void *memmove (void *, const void *, size_t)
+  __asm (ASMNAME ("my_memmove"));
 extern void *memset (void *, int, size_t)
   __asm (ASMNAME ("my_memset"));
 extern void bzero (void *, size_t)