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-- along with raytrac. If not, see <http://www.gnu.org/licenses/>
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-- along with raytrac. If not, see <http://www.gnu.org/licenses/>
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library ieee;
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library ieee;
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use ieee.std_logic_1164.all;
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use ieee.std_logic_1164.all;
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use ieee.std_logic_arith.all;
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use ieee.std_logic_unsigned.all;
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use ieee.std_logic_unsigned.all;
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use work.arithpack.all;
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use ieee.math_real.all;
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--use work.arithpack.all;
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entity RLshifter is
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entity RLshifter is
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generic (
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generic (
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shiftFunction : string := "SQUARE_ROOT"
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shiftFunction : string := "SQUARE_ROOT";
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mantissa_width : integer := 18;
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mantissa_width : integer := 18;
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width : integer := 32
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width : integer := 32
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);
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);
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port (
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port (
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architecture RLshifter_arch of RLshifter is
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architecture RLshifter_arch of RLshifter is
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begin
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begin
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leftShift:
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leftShift:
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if shiftFunction="SQUARE_ROOT" generate
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if shiftFunction="SQUARE_ROOT" generate
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sqroot:
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sqroot:
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process (mantis, exp)
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process (mantis, exp)
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variable expi : integer := conv_integer(exp);
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variable expi : integer;
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begin
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begin
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result(width-1 downto expi+1) <= (others=>'0');
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expi := conv_integer(exp);
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result(expi downto 0) <= mantissa(mantissa_width-1 downto mantissa_width-1-exp);
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lupe:
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end sqroot;
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for i in width-1 downto 0 loop
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if i>expi then
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result(i)<='0';
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else
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result(i)<=mantis(mantissa_width-1-expi+i);
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end if;
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end loop lupe;
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end process sqroot;
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end generate leftShift;
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end generate leftShift;
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rightShift:
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rightShift:
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if shiftFunction="INVERSION" generate
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if shiftFunction="INVERSION" generate
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inverse:
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inverse:
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process (mantis,exp)
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process (mantis,exp)
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variable expi : integer := conv_integer(exp);
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variable expi : integer ;
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begin
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begin
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if expi>0 then
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expi:= conv_integer(exp);
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result (width-1 downto width-expi) <= (others => '0');
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end if;
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for i in width-1 downto 0 loop
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if mantissa_width+expi<width then
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if i<=width-1-expi and i>=width-expi-mantissa_width then
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result (width-1-expi downto width-mantissa_width) <= mantisa(mantissa_width-1 downto 0);
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result(i)
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result (width-mantissa_width-1 downto 0) <= (others => '0');
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<=mantis(mantissa_width-width+expi+i);
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else
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else
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result (width-1-expi downto 0) <= mantisa(mantisa_width-1 downto mantissa_width-width+expi);
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result(i)<='0';
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end if;
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end if;
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end loop;
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end inverse;
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end process inverse;
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end generate rightShift;
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end RLshifter_arch;
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end RLshifter_arch;
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No newline at end of file
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No newline at end of file
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