Function shift_bitmap_down

common/bolt11.c:483–495

}

static void shift_bitmap_down(u8 *bitmap, size_t bits)
{
	u8 prev = 0;
	assert(bits < CHAR_BIT);

	for (size_t i = 0; i < tal_bytelen(bitmap); i++) {
		/* Save top bits for next one */
		u8 v = bitmap[i];
		bitmap[i] = (prev | (v >> bits));
		prev = (v << (8 - bits));
	}
	assert(prev == 0);
}

/* BOLT #11:
 *