good changes from openpilot_compile2 (#2000)

* good changed from openpilot_compile2

* float32 image type was wrong

* cleaner way to write that + a test

test/test_schedule.py

@@ -322,5 +322,10 @@ class TestSchedule(unittest.TestCase):
     out = x.permute(0,2,3,1).contiguous()
     check_schedule(out, 2, filter_loadops=False)
 
+  def test_double_from(self):
+    x = Tensor([1,2,3,4])
+    out = x.to('cpu')
+    check_schedule(out, 0, filter_loadops=False)
+
 if __name__ == '__main__':
   unittest.main(verbosity=2)