diff --git a/lib/aarch64/misc_helpers.S b/lib/aarch64/misc_helpers.S
index 439ca28..f605bf4 100644
--- a/lib/aarch64/misc_helpers.S
+++ b/lib/aarch64/misc_helpers.S
@@ -30,6 +30,7 @@
 
 #include <arch.h>
 #include <asm_macros.S>
+#include <assert_macros.S>
 
 	.globl	get_afflvl_shift
 	.globl	mpidr_mask_lower_afflvls
@@ -46,7 +47,6 @@
 	.globl	enable_vfp
 #endif
 
-
 func get_afflvl_shift
 	cmp	x0, #3
 	cinc	x0, x0, eq
@@ -79,6 +79,10 @@
  * -----------------------------------------------------------------------
  */
 func zeromem16
+#if ASM_ASSERTION
+	tst	x0, #0xf
+	ASM_ASSERT(eq)
+#endif
 	add	x2, x0, x1
 /* zero 16 bytes at a time */
 z_loop16:
@@ -105,6 +109,11 @@
  * --------------------------------------------------------------------------
  */
 func memcpy16
+#if ASM_ASSERTION
+	orr	x3, x0, x1
+	tst	x3, #0xf
+	ASM_ASSERT(eq)
+#endif
 /* copy 16 bytes at a time */
 m_loop16:
 	cmp	x2, #16
@@ -145,7 +154,6 @@
 	mov	x1, #(SCTLR_M_BIT | SCTLR_C_BIT | SCTLR_I_BIT)
 	b	do_disable_mmu
 
-
 /* ---------------------------------------------------------------------------
  * Enable the use of VFP at EL3
  * ---------------------------------------------------------------------------