diff options
| -rwxr-xr-x | libraries/openieee/build_numeric.py | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/libraries/openieee/build_numeric.py b/libraries/openieee/build_numeric.py index fa02580de..5eef89b2a 100755 --- a/libraries/openieee/build_numeric.py +++ b/libraries/openieee/build_numeric.py @@ -785,27 +785,30 @@ def disp_divmod(): -- No 'X'. procedure divmod (num, dem : UNSIGNED; quot, remain : out UNSIGNED) is + -- An extra bit is needed so that it is always possible that DEM >= REG. variable reg : unsigned (dem'left + 1 downto 0) := (others => '0'); variable sub : unsigned (dem'range) := (others => '0'); variable carry, d : """ + logic_type () + """; begin for i in num'range loop - -- Shift + -- Shift to add a new bit from NUM to REG. reg (reg'left downto 1) := reg (reg'left - 1 downto 0); reg (0) := num (i); - -- Substract + -- Substract: REG - DEM carry := '1'; for j in dem'reverse_range loop d := not dem (j); sub (j) := compute_sum (carry, reg (j), d); carry := compute_carry (carry, reg (j), d); end loop; + -- Do not forget the extra bit in REG. carry := compute_carry (carry, reg (reg'left), '1'); -- Test if carry = '0' then - -- Greater than + -- REG < DEM quot (i) := '0'; else + -- REG >= DEM: do the substraction quot (i) := '1'; reg (reg'left) := '0'; reg (sub'range) := sub; |