diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index ebad5cb5a79..1baa50cb1b9 100644
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -7317,7 +7317,11 @@ simplify_context::simplify_subreg (machine_mode outermode, rtx op,
          have instruction to move the whole thing.  */
       && (! MEM_VOLATILE_P (op)
 	  || ! have_insn_for (SET, innermode))
-      && !(STRICT_ALIGNMENT && MEM_ALIGN (op) < GET_MODE_ALIGNMENT (outermode))
+      /* On STRICT_ALIGNMENT targets, don't allow the alignment to be increased
+	 if the inner object is already naturally aligned.  */
+      && !(STRICT_ALIGNMENT
+	   && MEM_ALIGN (op) >= GET_MODE_ALIGNMENT (innermode)
+	   && MEM_ALIGN (op) < GET_MODE_ALIGNMENT (outermode))
       && known_le (outersize, innersize))
     return adjust_address_nv (op, outermode, byte);