#ifdef CONFIG_VMAP_STACK
/*
* Test whether the SP has overflowed, without corrupting a GPR.
- * Task and IRQ stacks are aligned to (1 << THREAD_SHIFT).
+ * Task and IRQ stacks are aligned so that SP & (1 << THREAD_SHIFT)
+ * should always be zero.
*/
add sp, sp, x0 // sp' = sp + x0
sub x0, sp, x0 // x0' = sp' - x0 = (sp + x0) - x0 = sp