add docs for clz

diff --git a/src/soc/fu/div/experiment/goldschmidt_div_sqrt.py b/src/soc/fu/div/experiment/goldschmidt_div_sqrt.py
index 3801b200abe5f04e5968e6565c5f307465650967..ea0ddda0763c6847336589ec38cc8b5426013ba5 100644 (file)
--- a/src/soc/fu/div/experiment/goldschmidt_div_sqrt.py
+++ b/src/soc/fu/div/experiment/goldschmidt_div_sqrt.py
@@ -941,6 +941,7 @@ class GoldschmidtDivParams(GoldschmidtDivParamsBase):
 
 
 def clz(v, wid):
+    """count leading zeros -- handy for debugging."""
     assert isinstance(wid, int)
     assert isinstance(v, int) and 0 <= v < (1 << wid)
     return (1 << wid).bit_length() - v.bit_length()