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diff --git a/libraries/ieee2008/fixed_generic_pkg-body.vhdl b/libraries/ieee2008/fixed_generic_pkg-body.vhdl new file mode 100644 index 0000000..24842a9 --- /dev/null +++ b/libraries/ieee2008/fixed_generic_pkg-body.vhdl @@ -0,0 +1,6365 @@ +-- -------------------------------------------------------------------- +-- +-- Copyright © 2008 by IEEE. All rights reserved. +-- +-- This source file is an essential part of IEEE Std 1076-2008, +-- IEEE Standard VHDL Language Reference Manual. This source file may not be +-- copied, sold, or included with software that is sold without written +-- permission from the IEEE Standards Department. This source file may be +-- copied for individual use between licensed users. This source file is +-- provided on an AS IS basis. The IEEE disclaims ANY WARRANTY EXPRESS OR +-- IMPLIED INCLUDING ANY WARRANTY OF MERCHANTABILITY AND FITNESS FOR USE +-- FOR A PARTICULAR PURPOSE. The user of the source file shall indemnify +-- and hold IEEE harmless from any damages or liability arising out of the +-- use thereof. +-- +-- Title : Fixed-point package (Generic package body) +-- : +-- Library : This package shall be compiled into a library +-- : symbolically named IEEE. +-- : +-- Developers: Accellera VHDL-TC and IEEE P1076 Working Group +-- : +-- Purpose : This packages defines basic binary fixed point arithmetic +-- : arithmetic functions +-- : +-- Note : This package may be modified to include additional data +-- : required by tools, but it must in no way change the +-- : external interfaces or simulation behavior of the +-- : description. It is permissible to add comments and/or +-- : attributes to the package declarations, but not to change +-- : or delete any original lines of the package declaration. +-- : The package body may be changed only in accordance with +-- : the terms of Clause 16 of this standard. +-- : +-- -------------------------------------------------------------------- +-- $Revision: 1220 $ +-- $Date: 2008-04-10 17:16:09 +0930 (Thu, 10 Apr 2008) $ +-- -------------------------------------------------------------------- + +library IEEE; +use IEEE.MATH_REAL.all; + +package body fixed_generic_pkg is + -- Author David Bishop (dbishop@vhdl.org) + -- Other contributers: Jim Lewis, Yannick Grugni, Ryan W. Hilton + -- null array constants + constant NAUF : UNRESOLVED_ufixed (0 downto 1) := (others => '0'); + constant NASF : UNRESOLVED_sfixed (0 downto 1) := (others => '0'); + constant NSLV : STD_ULOGIC_VECTOR (0 downto 1) := (others => '0'); + + -- This differed constant will tell you if the package body is synthesizable + -- or implemented as real numbers, set to "true" if synthesizable. + constant fixedsynth_or_real : BOOLEAN := true; + + -- Special version of "minimum" to do some boundary checking without errors + function mins (l, r : INTEGER) + return INTEGER is + begin -- function mins + if (L = INTEGER'low or R = INTEGER'low) then + return 0; -- error condition, silent + end if; + return minimum (L, R); + end function mins; + + -- Special version of "minimum" to do some boundary checking with errors + function mine (l, r : INTEGER) + return INTEGER is + begin -- function mine + if (L = INTEGER'low or R = INTEGER'low) then + report fixed_generic_pkg'instance_name + & " Unbounded number passed, was a literal used?" + severity error; + return 0; + end if; + return minimum (L, R); + end function mine; + + -- The following functions are used only internally. Every function + -- calls "cleanvec" either directly or indirectly. + -- purpose: Fixes "downto" problem and resolves meta states + function cleanvec ( + arg : UNRESOLVED_sfixed) -- input + return UNRESOLVED_sfixed + is + constant left_index : INTEGER := maximum(arg'left, arg'right); + constant right_index : INTEGER := mins(arg'left, arg'right); + variable result : UNRESOLVED_sfixed (arg'range); + begin -- function cleanvec + assert not (arg'ascending and (arg'low /= INTEGER'low)) + report fixed_generic_pkg'instance_name + & " Vector passed using a ""to"" range, expected is ""downto""" + severity error; + return arg; + end function cleanvec; + + -- purpose: Fixes "downto" problem and resolves meta states + function cleanvec ( + arg : UNRESOLVED_ufixed) -- input + return UNRESOLVED_ufixed + is + constant left_index : INTEGER := maximum(arg'left, arg'right); + constant right_index : INTEGER := mins(arg'left, arg'right); + variable result : UNRESOLVED_ufixed (arg'range); + begin -- function cleanvec + assert not (arg'ascending and (arg'low /= INTEGER'low)) + report fixed_generic_pkg'instance_name + & " Vector passed using a ""to"" range, expected is ""downto""" + severity error; + return arg; + end function cleanvec; + + -- Type convert a "unsigned" into a "ufixed", used internally + function to_fixed ( + arg : UNRESOLVED_UNSIGNED; -- shifted vector + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (left_index downto right_index); + begin -- function to_fixed + result := UNRESOLVED_ufixed(arg); + return result; + end function to_fixed; + + -- Type convert a "signed" into an "sfixed", used internally + function to_fixed ( + arg : UNRESOLVED_SIGNED; -- shifted vector + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (left_index downto right_index); + begin -- function to_fixed + result := UNRESOLVED_sfixed(arg); + return result; + end function to_fixed; + + -- Type convert a "ufixed" into an "unsigned", used internally + function to_uns ( + arg : UNRESOLVED_ufixed) -- fp vector + return UNRESOLVED_UNSIGNED + is + subtype t is UNRESOLVED_UNSIGNED(arg'high - arg'low downto 0); + variable slv : t; + begin -- function to_uns + slv := t(arg); + return slv; + end function to_uns; + + -- Type convert an "sfixed" into a "signed", used internally + function to_s ( + arg : UNRESOLVED_sfixed) -- fp vector + return UNRESOLVED_SIGNED + is + subtype t is UNRESOLVED_SIGNED(arg'high - arg'low downto 0); + variable slv : t; + begin -- function to_s + slv := t(arg); + return slv; + end function to_s; + + -- adds 1 to the LSB of the number + procedure round_up (arg : in UNRESOLVED_ufixed; + result : out UNRESOLVED_ufixed; + overflowx : out BOOLEAN) is + variable arguns, resuns : UNRESOLVED_UNSIGNED (arg'high-arg'low+1 downto 0) + := (others => '0'); + begin -- round_up + arguns (arguns'high-1 downto 0) := to_uns (arg); + resuns := arguns + 1; + result := to_fixed(resuns(arg'high-arg'low + downto 0), arg'high, arg'low); + overflowx := (resuns(resuns'high) = '1'); + end procedure round_up; + + -- adds 1 to the LSB of the number + procedure round_up (arg : in UNRESOLVED_sfixed; + result : out UNRESOLVED_sfixed; + overflowx : out BOOLEAN) is + variable args, ress : UNRESOLVED_SIGNED (arg'high-arg'low+1 downto 0); + begin -- round_up + args (args'high-1 downto 0) := to_s (arg); + args(args'high) := arg(arg'high); -- sign extend + ress := args + 1; + result := to_fixed(ress (ress'high-1 + downto 0), arg'high, arg'low); + overflowx := ((arg(arg'high) /= ress(ress'high-1)) + and (or (STD_ULOGIC_VECTOR(ress)) /= '0')); + end procedure round_up; + + -- Rounding - Performs a "round_nearest" (IEEE 754) which rounds up + -- when the remainder is > 0.5. If the remainder IS 0.5 then if the + -- bottom bit is a "1" it is rounded, otherwise it remains the same. + function round_fixed (arg : UNRESOLVED_ufixed; + remainder : UNRESOLVED_ufixed; + overflow_style : fixed_overflow_style_type := fixed_overflow_style) + return UNRESOLVED_ufixed + is + variable rounds : BOOLEAN; + variable round_overflow : BOOLEAN; + variable result : UNRESOLVED_ufixed (arg'range); + begin + rounds := false; + if (remainder'length > 1) then + if (remainder (remainder'high) = '1') then + rounds := (arg(arg'low) = '1') + or (or (to_sulv(remainder(remainder'high-1 downto + remainder'low))) = '1'); + end if; + else + rounds := (arg(arg'low) = '1') and (remainder (remainder'high) = '1'); + end if; + if rounds then + round_up(arg => arg, + result => result, + overflowx => round_overflow); + else + result := arg; + end if; + if (overflow_style = fixed_saturate) and round_overflow then + result := saturate (result'high, result'low); + end if; + return result; + end function round_fixed; + + -- Rounding case statement + function round_fixed (arg : UNRESOLVED_sfixed; + remainder : UNRESOLVED_sfixed; + overflow_style : fixed_overflow_style_type := fixed_overflow_style) + return UNRESOLVED_sfixed + is + variable rounds : BOOLEAN; + variable round_overflow : BOOLEAN; + variable result : UNRESOLVED_sfixed (arg'range); + begin + rounds := false; + if (remainder'length > 1) then + if (remainder (remainder'high) = '1') then + rounds := (arg(arg'low) = '1') + or (or (to_sulv(remainder(remainder'high-1 downto + remainder'low))) = '1'); + end if; + else + rounds := (arg(arg'low) = '1') and (remainder (remainder'high) = '1'); + end if; + if rounds then + round_up(arg => arg, + result => result, + overflowx => round_overflow); + else + result := arg; + end if; + if round_overflow then + if (overflow_style = fixed_saturate) then + if arg(arg'high) = '0' then + result := saturate (result'high, result'low); + else + result := not saturate (result'high, result'low); + end if; + -- Sign bit not fixed when wrapping + end if; + end if; + return result; + end function round_fixed; + + -- converts an sfixed into a ufixed. The output is the same length as the + -- input, because abs("1000") = "1000" = 8. + function to_ufixed ( + arg : UNRESOLVED_sfixed) + return UNRESOLVED_ufixed + is + constant left_index : INTEGER := arg'high; + constant right_index : INTEGER := mine(arg'low, arg'low); + variable xarg : UNRESOLVED_sfixed(left_index+1 downto right_index); + variable result : UNRESOLVED_ufixed(left_index downto right_index); + begin + if arg'length < 1 then + return NAUF; + end if; + xarg := abs(arg); + result := UNRESOLVED_ufixed (xarg (left_index downto right_index)); + return result; + end function to_ufixed; + +----------------------------------------------------------------------------- +-- Visible functions +----------------------------------------------------------------------------- + + -- Conversion functions. These are needed for synthesis where typically + -- the only input and output type is a std_logic_vector. + function to_sulv ( + arg : UNRESOLVED_ufixed) -- fixed point vector + return STD_ULOGIC_VECTOR + is + variable result : STD_ULOGIC_VECTOR (arg'length-1 downto 0); + begin + if arg'length < 1 then + return NSLV; + end if; + result := STD_ULOGIC_VECTOR (arg); + return result; + end function to_sulv; + + function to_sulv ( + arg : UNRESOLVED_sfixed) -- fixed point vector + return STD_ULOGIC_VECTOR + is + variable result : STD_ULOGIC_VECTOR (arg'length-1 downto 0); + begin + if arg'length < 1 then + return NSLV; + end if; + result := STD_ULOGIC_VECTOR (arg); + return result; + end function to_sulv; + + function to_slv ( + arg : UNRESOLVED_ufixed) -- fixed point vector + return STD_LOGIC_VECTOR is + begin + return to_sulv(arg); + end function to_slv; + + function to_slv ( + arg : UNRESOLVED_sfixed) -- fixed point vector + return STD_LOGIC_VECTOR is + begin + return to_sulv(arg); + end function to_slv; + + function to_ufixed ( + arg : STD_ULOGIC_VECTOR; -- shifted vector + constant left_index : INTEGER; + constant right_index : INTEGER) + return unresolved_ufixed + is + variable result : UNRESOLVED_ufixed (left_index downto right_index); + begin + if (arg'length < 1 or right_index > left_index) then + return NAUF; + end if; + if (arg'length /= result'length) then + report fixed_generic_pkg'instance_name & "TO_UFIXED(SLV) " + & "Vector lengths do not match. Input length is " + & INTEGER'image(arg'length) & " and output will be " + & INTEGER'image(result'length) & " wide." + severity error; + return NAUF; + else + result := to_fixed (arg => UNRESOLVED_UNSIGNED(arg), + left_index => left_index, + right_index => right_index); + return result; + end if; + end function to_ufixed; + + function to_sfixed ( + arg : STD_ULOGIC_VECTOR; -- shifted vector + constant left_index : INTEGER; + constant right_index : INTEGER) + return unresolved_sfixed + is + variable result : UNRESOLVED_sfixed (left_index downto right_index); + begin + if (arg'length < 1 or right_index > left_index) then + return NASF; + end if; + if (arg'length /= result'length) then + report fixed_generic_pkg'instance_name & "TO_SFIXED(SLV) " + & "Vector lengths do not match. Input length is " + & INTEGER'image(arg'length) & " and output will be " + & INTEGER'image(result'length) & " wide." + severity error; + return NASF; + else + result := to_fixed (arg => UNRESOLVED_SIGNED(arg), + left_index => left_index, + right_index => right_index); + return result; + end if; + end function to_sfixed; + + -- Two's complement number, Grows the vector by 1 bit. + -- because "abs (1000.000) = 01000.000" or abs(-16) = 16. + function "abs" ( + arg : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed + is + constant left_index : INTEGER := arg'high; + constant right_index : INTEGER := mine(arg'low, arg'low); + variable ressns : UNRESOLVED_SIGNED (arg'length downto 0); + variable result : UNRESOLVED_sfixed (left_index+1 downto right_index); + begin + if (arg'length < 1 or result'length < 1) then + return NASF; + end if; + ressns (arg'length-1 downto 0) := to_s (cleanvec (arg)); + ressns (arg'length) := ressns (arg'length-1); -- expand sign bit + result := to_fixed (abs(ressns), left_index+1, right_index); + return result; + end function "abs"; + + -- also grows the vector by 1 bit. + function "-" ( + arg : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed + is + constant left_index : INTEGER := arg'high+1; + constant right_index : INTEGER := mine(arg'low, arg'low); + variable ressns : UNRESOLVED_SIGNED (arg'length downto 0); + variable result : UNRESOLVED_sfixed (left_index downto right_index); + begin + if (arg'length < 1 or result'length < 1) then + return NASF; + end if; + ressns (arg'length-1 downto 0) := to_s (cleanvec(arg)); + ressns (arg'length) := ressns (arg'length-1); -- expand sign bit + result := to_fixed (-ressns, left_index, right_index); + return result; + end function "-"; + + -- Addition + function "+" ( + l, r : UNRESOLVED_ufixed) -- ufixed(a downto b) + ufixed(c downto d) = + return UNRESOLVED_ufixed -- ufixed(max(a,c)+1 downto min(b,d)) + is + constant left_index : INTEGER := maximum(l'high, r'high)+1; + constant right_index : INTEGER := mine(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable result : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (left_index-right_index + downto 0); + variable result_slv : UNRESOLVED_UNSIGNED (left_index-right_index + downto 0); + begin + if (l'length < 1 or r'length < 1 or result'length < 1) then + return NAUF; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + result_slv := lslv + rslv; + result := to_fixed(result_slv, left_index, right_index); + return result; + end function "+"; + + function "+" ( + l, r : UNRESOLVED_sfixed) -- sfixed(a downto b) + sfixed(c downto d) = + return UNRESOLVED_sfixed -- sfixed(max(a,c)+1 downto min(b,d)) + is + constant left_index : INTEGER := maximum(l'high, r'high)+1; + constant right_index : INTEGER := mine(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable result : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (left_index-right_index downto 0); + variable result_slv : UNRESOLVED_SIGNED (left_index-right_index downto 0); + begin + if (l'length < 1 or r'length < 1 or result'length < 1) then + return NASF; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + result_slv := lslv + rslv; + result := to_fixed(result_slv, left_index, right_index); + return result; + end function "+"; + + -- Subtraction + function "-" ( + l, r : UNRESOLVED_ufixed) -- ufixed(a downto b) - ufixed(c downto d) = + return UNRESOLVED_ufixed -- ufixed(max(a,c)+1 downto min(b,d)) + is + constant left_index : INTEGER := maximum(l'high, r'high)+1; + constant right_index : INTEGER := mine(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable result : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (left_index-right_index + downto 0); + variable result_slv : UNRESOLVED_UNSIGNED (left_index-right_index + downto 0); + begin + if (l'length < 1 or r'length < 1 or result'length < 1) then + return NAUF; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + result_slv := lslv - rslv; + result := to_fixed(result_slv, left_index, right_index); + return result; + end function "-"; + + function "-" ( + l, r : UNRESOLVED_sfixed) -- sfixed(a downto b) - sfixed(c downto d) = + return UNRESOLVED_sfixed -- sfixed(max(a,c)+1 downto min(b,d)) + is + constant left_index : INTEGER := maximum(l'high, r'high)+1; + constant right_index : INTEGER := mine(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable result : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (left_index-right_index downto 0); + variable result_slv : UNRESOLVED_SIGNED (left_index-right_index downto 0); + begin + if (l'length < 1 or r'length < 1 or result'length < 1) then + return NASF; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + result_slv := lslv - rslv; + result := to_fixed(result_slv, left_index, right_index); + return result; + end function "-"; + + function "*" ( + l, r : UNRESOLVED_ufixed) -- ufixed(a downto b) * ufixed(c downto d) = + return UNRESOLVED_ufixed -- ufixed(a+c+1 downto b+d) + is + variable lslv : UNRESOLVED_UNSIGNED (l'length-1 downto 0); + variable rslv : UNRESOLVED_UNSIGNED (r'length-1 downto 0); + variable result_slv : UNRESOLVED_UNSIGNED (r'length+l'length-1 downto 0); + variable result : UNRESOLVED_ufixed (l'high + r'high+1 downto + mine(l'low, l'low) + mine(r'low, r'low)); + begin + if (l'length < 1 or r'length < 1 or + result'length /= result_slv'length) then + return NAUF; + end if; + lslv := to_uns (cleanvec(l)); + rslv := to_uns (cleanvec(r)); + result_slv := lslv * rslv; + result := to_fixed (result_slv, result'high, result'low); + return result; + end function "*"; + + function "*" ( + l, r : UNRESOLVED_sfixed) -- sfixed(a downto b) * sfixed(c downto d) = + return UNRESOLVED_sfixed -- sfixed(a+c+1 downto b+d) + is + variable lslv : UNRESOLVED_SIGNED (l'length-1 downto 0); + variable rslv : UNRESOLVED_SIGNED (r'length-1 downto 0); + variable result_slv : UNRESOLVED_SIGNED (r'length+l'length-1 downto 0); + variable result : UNRESOLVED_sfixed (l'high + r'high+1 downto + mine(l'low, l'low) + mine(r'low, r'low)); + begin + if (l'length < 1 or r'length < 1 or + result'length /= result_slv'length) then + return NASF; + end if; + lslv := to_s (cleanvec(l)); + rslv := to_s (cleanvec(r)); + result_slv := lslv * rslv; + result := to_fixed (result_slv, result'high, result'low); + return result; + end function "*"; + + function "/" ( + l, r : UNRESOLVED_ufixed) -- ufixed(a downto b) / ufixed(c downto d) = + return UNRESOLVED_ufixed is -- ufixed(a-d downto b-c-1) + begin + return divide (l, r); + end function "/"; + + function "/" ( + l, r : UNRESOLVED_sfixed) -- sfixed(a downto b) / sfixed(c downto d) = + return UNRESOLVED_sfixed is -- sfixed(a-d+1 downto b-c) + begin + return divide (l, r); + end function "/"; + + -- This version of divide gives the user more control + -- ufixed(a downto b) / ufixed(c downto d) = ufixed(a-d downto b-c-1) + function divide ( + l, r : UNRESOLVED_ufixed; + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (l'high - mine(r'low, r'low) downto + mine (l'low, l'low) - r'high -1); + variable dresult : UNRESOLVED_ufixed (result'high downto result'low -guard_bits); + variable lresize : UNRESOLVED_ufixed (l'high downto l'high - dresult'length+1); + variable lslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + variable rslv : UNRESOLVED_UNSIGNED (r'length-1 downto 0); + variable result_slv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1 or + mins(r'low, r'low) /= r'low or mins(l'low, l'low) /= l'low) then + return NAUF; + end if; + lresize := resize (arg => l, + left_index => lresize'high, + right_index => lresize'low, + overflow_style => fixed_wrap, -- vector only grows + round_style => fixed_truncate); + lslv := to_uns (cleanvec (lresize)); + rslv := to_uns (cleanvec (r)); + if (rslv = 0) then + report fixed_generic_pkg'instance_name + & "DIVIDE(ufixed) Division by zero" severity error; + result := saturate (result'high, result'low); -- saturate + else + result_slv := lslv / rslv; + dresult := to_fixed (result_slv, dresult'high, dresult'low); + result := resize (arg => dresult, + left_index => result'high, + right_index => result'low, + overflow_style => fixed_wrap, -- overflow impossible + round_style => round_style); + end if; + return result; + end function divide; + + -- sfixed(a downto b) / sfixed(c downto d) = sfixed(a-d+1 downto b-c) + function divide ( + l, r : UNRESOLVED_sfixed; + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (l'high - mine(r'low, r'low) + 1 downto + mine (l'low, l'low) - r'high); + variable dresult : UNRESOLVED_sfixed (result'high downto result'low-guard_bits); + variable lresize : UNRESOLVED_sfixed (l'high+1 downto l'high+1 -dresult'length+1); + variable lslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + variable rslv : UNRESOLVED_SIGNED (r'length-1 downto 0); + variable result_slv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1 or + mins(r'low, r'low) /= r'low or mins(l'low, l'low) /= l'low) then + return NASF; + end if; + lresize := resize (arg => l, + left_index => lresize'high, + right_index => lresize'low, + overflow_style => fixed_wrap, -- vector only grows + round_style => fixed_truncate); + lslv := to_s (cleanvec (lresize)); + rslv := to_s (cleanvec (r)); + if (rslv = 0) then + report fixed_generic_pkg'instance_name + & "DIVIDE(sfixed) Division by zero" severity error; + result := saturate (result'high, result'low); + else + result_slv := lslv / rslv; + dresult := to_fixed (result_slv, dresult'high, dresult'low); + result := resize (arg => dresult, + left_index => result'high, + right_index => result'low, + overflow_style => fixed_wrap, -- overflow impossible + round_style => round_style); + end if; + return result; + end function divide; + + -- 1 / ufixed(a downto b) = ufixed(-b downto -a-1) + function reciprocal ( + arg : UNRESOLVED_ufixed; -- fixed point input + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) + return UNRESOLVED_ufixed + is + constant one : UNRESOLVED_ufixed (0 downto 0) := "1"; + begin + return divide (l => one, + r => arg, + round_style => round_style, + guard_bits => guard_bits); + end function reciprocal; + + -- 1 / sfixed(a downto b) = sfixed(-b+1 downto -a) + function reciprocal ( + arg : UNRESOLVED_sfixed; -- fixed point input + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) + return UNRESOLVED_sfixed + is + constant one : UNRESOLVED_sfixed (1 downto 0) := "01"; -- extra bit. + variable resultx : UNRESOLVED_sfixed (-mine(arg'low, arg'low)+2 downto -arg'high); + begin + if (arg'length < 1 or resultx'length < 1) then + return NASF; + else + resultx := divide (l => one, + r => arg, + round_style => round_style, + guard_bits => guard_bits); + return resultx (resultx'high-1 downto resultx'low); -- remove extra bit + end if; + end function reciprocal; + + -- ufixed (a downto b) rem ufixed (c downto d) + -- = ufixed (min(a,c) downto min(b,d)) + function "rem" ( + l, r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return remainder (l, r); + end function "rem"; + + -- remainder + -- sfixed (a downto b) rem sfixed (c downto d) + -- = sfixed (min(a,c) downto min(b,d)) + function "rem" ( + l, r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return remainder (l, r); + end function "rem"; + + -- ufixed (a downto b) rem ufixed (c downto d) + -- = ufixed (min(a,c) downto min(b,d)) + function remainder ( + l, r : UNRESOLVED_ufixed; -- fixed point input + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (minimum(l'high, r'high) downto + mine(l'low, r'low)); + variable lresize : UNRESOLVED_ufixed (maximum(l'high, r'low) downto + mins(r'low, r'low)-guard_bits); + variable rresize : UNRESOLVED_ufixed (r'high downto r'low-guard_bits); + variable dresult : UNRESOLVED_ufixed (rresize'range); + variable lslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + variable rslv : UNRESOLVED_UNSIGNED (rresize'length-1 downto 0); + variable result_slv : UNRESOLVED_UNSIGNED (rslv'range); + begin + if (l'length < 1 or r'length < 1 or + mins(r'low, r'low) /= r'low or mins(l'low, l'low) /= l'low) then + return NAUF; + end if; + lresize := resize (arg => l, + left_index => lresize'high, + right_index => lresize'low, + overflow_style => fixed_wrap, -- vector only grows + round_style => fixed_truncate); + lslv := to_uns (lresize); + rresize := resize (arg => r, + left_index => rresize'high, + right_index => rresize'low, + overflow_style => fixed_wrap, -- vector only grows + round_style => fixed_truncate); + rslv := to_uns (rresize); + if (rslv = 0) then + report fixed_generic_pkg'instance_name + & "remainder(ufixed) Division by zero" severity error; + result := saturate (result'high, result'low); -- saturate + else + if (r'low <= l'high) then + result_slv := lslv rem rslv; + dresult := to_fixed (result_slv, dresult'high, dresult'low); + result := resize (arg => dresult, + left_index => result'high, + right_index => result'low, + overflow_style => fixed_wrap, -- can't overflow + round_style => round_style); + end if; + if l'low < r'low then + result(mins(r'low-1, l'high) downto l'low) := + cleanvec(l(mins(r'low-1, l'high) downto l'low)); + end if; + end if; + return result; + end function remainder; + + -- remainder + -- sfixed (a downto b) rem sfixed (c downto d) + -- = sfixed (min(a,c) downto min(b,d)) + function remainder ( + l, r : UNRESOLVED_sfixed; -- fixed point input + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) + return UNRESOLVED_sfixed + is + variable l_abs : UNRESOLVED_ufixed (l'range); + variable r_abs : UNRESOLVED_ufixed (r'range); + variable result : UNRESOLVED_sfixed (minimum(r'high, l'high) downto + mine(r'low, l'low)); + variable neg_result : UNRESOLVED_sfixed (minimum(r'high, l'high)+1 downto + mins(r'low, l'low)); + begin + if (l'length < 1 or r'length < 1 or + mins(r'low, r'low) /= r'low or mins(l'low, l'low) /= l'low) then + return NASF; + end if; + l_abs := to_ufixed (l); + r_abs := to_ufixed (r); + result := UNRESOLVED_sfixed (remainder ( + l => l_abs, + r => r_abs, + round_style => round_style)); + neg_result := -result; + if l(l'high) = '1' then + result := neg_result(result'range); + end if; + return result; + end function remainder; + + -- modulo + -- ufixed (a downto b) mod ufixed (c downto d) + -- = ufixed (min(a,c) downto min(b, d)) + function "mod" ( + l, r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return modulo (l, r); + end function "mod"; + + -- sfixed (a downto b) mod sfixed (c downto d) + -- = sfixed (c downto min(b, d)) + function "mod" ( + l, r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return modulo(l, r); + end function "mod"; + + -- modulo + -- ufixed (a downto b) mod ufixed (c downto d) + -- = ufixed (min(a,c) downto min(b, d)) + function modulo ( + l, r : UNRESOLVED_ufixed; -- fixed point input + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) + return UNRESOLVED_ufixed is + begin + return remainder(l => l, + r => r, + round_style => round_style, + guard_bits => guard_bits); + end function modulo; + + -- sfixed (a downto b) mod sfixed (c downto d) + -- = sfixed (c downto min(b, d)) + function modulo ( + l, r : UNRESOLVED_sfixed; -- fixed point input + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) + return UNRESOLVED_sfixed + is + variable l_abs : UNRESOLVED_ufixed (l'range); + variable r_abs : UNRESOLVED_ufixed (r'range); + variable result : UNRESOLVED_sfixed (r'high downto + mine(r'low, l'low)); + variable dresult : UNRESOLVED_sfixed (minimum(r'high, l'high)+1 downto + mins(r'low, l'low)); + variable dresult_not_zero : BOOLEAN; + begin + if (l'length < 1 or r'length < 1 or + mins(r'low, r'low) /= r'low or mins(l'low, l'low) /= l'low) then + return NASF; + end if; + l_abs := to_ufixed (l); + r_abs := to_ufixed (r); + dresult := "0" & UNRESOLVED_sfixed(remainder (l => l_abs, + r => r_abs, + round_style => round_style)); + if (to_s(dresult) = 0) then + dresult_not_zero := false; + else + dresult_not_zero := true; + end if; + if to_x01(l(l'high)) = '1' and to_x01(r(r'high)) = '0' + and dresult_not_zero then + result := resize (arg => r - dresult, + left_index => result'high, + right_index => result'low, + overflow_style => overflow_style, + round_style => round_style); + elsif to_x01(l(l'high)) = '1' and to_x01(r(r'high)) = '1' then + result := resize (arg => -dresult, + left_index => result'high, + right_index => result'low, + overflow_style => overflow_style, + round_style => round_style); + elsif to_x01(l(l'high)) = '0' and to_x01(r(r'high)) = '1' + and dresult_not_zero then + result := resize (arg => dresult + r, + left_index => result'high, + right_index => result'low, + overflow_style => overflow_style, + round_style => round_style); + else + result := resize (arg => dresult, + left_index => result'high, + right_index => result'low, + overflow_style => overflow_style, + round_style => round_style); + end if; + return result; + end function modulo; + + -- Procedure for those who need an "accumulator" function + procedure add_carry ( + L, R : in UNRESOLVED_ufixed; + c_in : in STD_ULOGIC; + result : out UNRESOLVED_ufixed; + c_out : out STD_ULOGIC) is + constant left_index : INTEGER := maximum(l'high, r'high)+1; + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (left_index-right_index + downto 0); + variable result_slv : UNRESOLVED_UNSIGNED (left_index-right_index + downto 0); + variable cx : UNRESOLVED_UNSIGNED (0 downto 0); -- Carry in + begin + if (l'length < 1 or r'length < 1) then + result := NAUF; + c_out := '0'; + else + cx (0) := c_in; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + result_slv := lslv + rslv + cx; + c_out := result_slv(left_index); + result := to_fixed(result_slv (left_index-right_index-1 downto 0), + left_index-1, right_index); + end if; + end procedure add_carry; + + procedure add_carry ( + L, R : in UNRESOLVED_sfixed; + c_in : in STD_ULOGIC; + result : out UNRESOLVED_sfixed; + c_out : out STD_ULOGIC) is + constant left_index : INTEGER := maximum(l'high, r'high)+1; + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (left_index-right_index + downto 0); + variable result_slv : UNRESOLVED_SIGNED (left_index-right_index + downto 0); + variable cx : UNRESOLVED_SIGNED (1 downto 0); -- Carry in + begin + if (l'length < 1 or r'length < 1) then + result := NASF; + c_out := '0'; + else + cx (1) := '0'; + cx (0) := c_in; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + result_slv := lslv + rslv + cx; + c_out := result_slv(left_index); + result := to_fixed(result_slv (left_index-right_index-1 downto 0), + left_index-1, right_index); + end if; + end procedure add_carry; + + -- Scales the result by a power of 2. Width of input = width of output with + -- the decimal point moved. + function scalb (y : UNRESOLVED_ufixed; N : INTEGER) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (y'high+N downto y'low+N); + begin + if y'length < 1 then + return NAUF; + else + result := y; + return result; + end if; + end function scalb; + + function scalb (y : UNRESOLVED_ufixed; N : UNRESOLVED_SIGNED) + return UNRESOLVED_ufixed is + begin + return scalb (y => y, + N => to_integer(N)); + end function scalb; + + function scalb (y : UNRESOLVED_sfixed; N : INTEGER) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (y'high+N downto y'low+N); + begin + if y'length < 1 then + return NASF; + else + result := y; + return result; + end if; + end function scalb; + + function scalb (y : UNRESOLVED_sfixed; N : UNRESOLVED_SIGNED) + return UNRESOLVED_sfixed is + begin + return scalb (y => y, + N => to_integer(N)); + end function scalb; + + function Is_Negative (arg : UNRESOLVED_sfixed) return BOOLEAN is + begin + if to_X01(arg(arg'high)) = '1' then + return true; + else + return false; + end if; + end function Is_Negative; + + function find_rightmost (arg : UNRESOLVED_ufixed; y : STD_ULOGIC) + return INTEGER is + begin + for_loop : for i in arg'reverse_range loop + if arg(i) ?= y then + return i; + end if; + end loop; + return arg'high+1; -- return out of bounds 'high + end function find_rightmost; + + function find_leftmost (arg : UNRESOLVED_ufixed; y : STD_ULOGIC) + return INTEGER is + begin + for_loop : for i in arg'range loop + if arg(i) ?= y then + return i; + end if; + end loop; + return arg'low-1; -- return out of bounds 'low + end function find_leftmost; + + function find_rightmost (arg : UNRESOLVED_sfixed; y : STD_ULOGIC) + return INTEGER is + begin + for_loop : for i in arg'reverse_range loop + if arg(i) ?= y then + return i; + end if; + end loop; + return arg'high+1; -- return out of bounds 'high + end function find_rightmost; + + function find_leftmost (arg : UNRESOLVED_sfixed; y : STD_ULOGIC) + return INTEGER is + begin + for_loop : for i in arg'range loop + if arg(i) ?= y then + return i; + end if; + end loop; + return arg'low-1; -- return out of bounds 'low + end function find_leftmost; + + function "sll" (ARG : UNRESOLVED_ufixed; COUNT : INTEGER) + return UNRESOLVED_ufixed + is + variable argslv : UNRESOLVED_UNSIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_ufixed (arg'range); + begin + argslv := to_uns (arg); + argslv := argslv sll COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "sll"; + + function "srl" (ARG : UNRESOLVED_ufixed; COUNT : INTEGER) + return UNRESOLVED_ufixed + is + variable argslv : UNRESOLVED_UNSIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_ufixed (arg'range); + begin + argslv := to_uns (arg); + argslv := argslv srl COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "srl"; + + function "rol" (ARG : UNRESOLVED_ufixed; COUNT : INTEGER) + return UNRESOLVED_ufixed + is + variable argslv : UNRESOLVED_UNSIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_ufixed (arg'range); + begin + argslv := to_uns (arg); + argslv := argslv rol COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "rol"; + + function "ror" (ARG : UNRESOLVED_ufixed; COUNT : INTEGER) + return UNRESOLVED_ufixed + is + variable argslv : UNRESOLVED_UNSIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_ufixed (arg'range); + begin + argslv := to_uns (arg); + argslv := argslv ror COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "ror"; + + function "sla" (ARG : UNRESOLVED_ufixed; COUNT : INTEGER) + return UNRESOLVED_ufixed + is + variable argslv : UNRESOLVED_UNSIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_ufixed (arg'range); + begin + argslv := to_uns (arg); + -- Arithmetic shift on an unsigned is a logical shift + argslv := argslv sll COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "sla"; + + function "sra" (ARG : UNRESOLVED_ufixed; COUNT : INTEGER) + return UNRESOLVED_ufixed + is + variable argslv : UNRESOLVED_UNSIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_ufixed (arg'range); + begin + argslv := to_uns (arg); + -- Arithmetic shift on an unsigned is a logical shift + argslv := argslv srl COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "sra"; + + function "sll" (ARG : UNRESOLVED_sfixed; COUNT : INTEGER) + return UNRESOLVED_sfixed + is + variable argslv : UNRESOLVED_SIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_sfixed (arg'range); + begin + argslv := to_s (arg); + argslv := argslv sll COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "sll"; + + function "srl" (ARG : UNRESOLVED_sfixed; COUNT : INTEGER) + return UNRESOLVED_sfixed + is + variable argslv : UNRESOLVED_SIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_sfixed (arg'range); + begin + argslv := to_s (arg); + argslv := argslv srl COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "srl"; + + function "rol" (ARG : UNRESOLVED_sfixed; COUNT : INTEGER) + return UNRESOLVED_sfixed + is + variable argslv : UNRESOLVED_SIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_sfixed (arg'range); + begin + argslv := to_s (arg); + argslv := argslv rol COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "rol"; + + function "ror" (ARG : UNRESOLVED_sfixed; COUNT : INTEGER) + return UNRESOLVED_sfixed + is + variable argslv : UNRESOLVED_SIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_sfixed (arg'range); + begin + argslv := to_s (arg); + argslv := argslv ror COUNT; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "ror"; + + function "sla" (ARG : UNRESOLVED_sfixed; COUNT : INTEGER) + return UNRESOLVED_sfixed + is + variable argslv : UNRESOLVED_SIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_sfixed (arg'range); + begin + argslv := to_s (arg); + if COUNT > 0 then + -- Arithmetic shift left on a 2's complement number is a logic shift + argslv := argslv sll COUNT; + else + argslv := argslv sra -COUNT; + end if; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "sla"; + + function "sra" (ARG : UNRESOLVED_sfixed; COUNT : INTEGER) + return UNRESOLVED_sfixed + is + variable argslv : UNRESOLVED_SIGNED (arg'length-1 downto 0); + variable result : UNRESOLVED_sfixed (arg'range); + begin + argslv := to_s (arg); + if COUNT > 0 then + argslv := argslv sra COUNT; + else + -- Arithmetic shift left on a 2's complement number is a logic shift + argslv := argslv sll -COUNT; + end if; + result := to_fixed (argslv, result'high, result'low); + return result; + end function "sra"; + + -- Because some people want the older functions. + function SHIFT_LEFT (ARG : UNRESOLVED_ufixed; COUNT : NATURAL) + return UNRESOLVED_ufixed is + begin + if (ARG'length < 1) then + return NAUF; + end if; + return ARG sla COUNT; + end function SHIFT_LEFT; + + function SHIFT_RIGHT (ARG : UNRESOLVED_ufixed; COUNT : NATURAL) + return UNRESOLVED_ufixed is + begin + if (ARG'length < 1) then + return NAUF; + end if; + return ARG sra COUNT; + end function SHIFT_RIGHT; + + function SHIFT_LEFT (ARG : UNRESOLVED_sfixed; COUNT : NATURAL) + return UNRESOLVED_sfixed is + begin + if (ARG'length < 1) then + return NASF; + end if; + return ARG sla COUNT; + end function SHIFT_LEFT; + + function SHIFT_RIGHT (ARG : UNRESOLVED_sfixed; COUNT : NATURAL) + return UNRESOLVED_sfixed is + begin + if (ARG'length < 1) then + return NASF; + end if; + return ARG sra COUNT; + end function SHIFT_RIGHT; + + ---------------------------------------------------------------------------- + -- logical functions + ---------------------------------------------------------------------------- + function "not" (L : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + RESULT := not to_sulv(L); + return to_ufixed(RESULT, L'high, L'low); + end function "not"; + + function "and" (L, R : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) and to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """and"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_ufixed(RESULT, L'high, L'low); + end function "and"; + + function "or" (L, R : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) or to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """or"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_ufixed(RESULT, L'high, L'low); + end function "or"; + + function "nand" (L, R : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) nand to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """nand"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_ufixed(RESULT, L'high, L'low); + end function "nand"; + + function "nor" (L, R : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) nor to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """nor"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_ufixed(RESULT, L'high, L'low); + end function "nor"; + + function "xor" (L, R : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) xor to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """xor"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_ufixed(RESULT, L'high, L'low); + end function "xor"; + + function "xnor" (L, R : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) xnor to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """xnor"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_ufixed(RESULT, L'high, L'low); + end function "xnor"; + + function "not" (L : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + RESULT := not to_sulv(L); + return to_sfixed(RESULT, L'high, L'low); + end function "not"; + + function "and" (L, R : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) and to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """and"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_sfixed(RESULT, L'high, L'low); + end function "and"; + + function "or" (L, R : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) or to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """or"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_sfixed(RESULT, L'high, L'low); + end function "or"; + + function "nand" (L, R : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) nand to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """nand"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_sfixed(RESULT, L'high, L'low); + end function "nand"; + + function "nor" (L, R : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) nor to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """nor"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_sfixed(RESULT, L'high, L'low); + end function "nor"; + + function "xor" (L, R : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) xor to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """xor"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_sfixed(RESULT, L'high, L'low); + end function "xor"; + + function "xnor" (L, R : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + variable RESULT : STD_ULOGIC_VECTOR(L'length-1 downto 0); -- force downto + begin + if (L'high = R'high and L'low = R'low) then + RESULT := to_sulv(L) xnor to_sulv(R); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """xnor"": Range error L'RANGE /= R'RANGE" + severity warning; + RESULT := (others => 'X'); + end if; + return to_sfixed(RESULT, L'high, L'low); + end function "xnor"; + + -- Vector and std_ulogic functions, same as functions in numeric_std + function "and" (L : STD_ULOGIC; R : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (R'range); + begin + for i in result'range loop + result(i) := L and R(i); + end loop; + return result; + end function "and"; + + function "and" (L : UNRESOLVED_ufixed; R : STD_ULOGIC) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (L'range); + begin + for i in result'range loop + result(i) := L(i) and R; + end loop; + return result; + end function "and"; + + function "or" (L : STD_ULOGIC; R : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (R'range); + begin + for i in result'range loop + result(i) := L or R(i); + end loop; + return result; + end function "or"; + + function "or" (L : UNRESOLVED_ufixed; R : STD_ULOGIC) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (L'range); + begin + for i in result'range loop + result(i) := L(i) or R; + end loop; + return result; + end function "or"; + + function "nand" (L : STD_ULOGIC; R : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (R'range); + begin + for i in result'range loop + result(i) := L nand R(i); + end loop; + return result; + end function "nand"; + + function "nand" (L : UNRESOLVED_ufixed; R : STD_ULOGIC) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (L'range); + begin + for i in result'range loop + result(i) := L(i) nand R; + end loop; + return result; + end function "nand"; + + function "nor" (L : STD_ULOGIC; R : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (R'range); + begin + for i in result'range loop + result(i) := L nor R(i); + end loop; + return result; + end function "nor"; + + function "nor" (L : UNRESOLVED_ufixed; R : STD_ULOGIC) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (L'range); + begin + for i in result'range loop + result(i) := L(i) nor R; + end loop; + return result; + end function "nor"; + + function "xor" (L : STD_ULOGIC; R : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (R'range); + begin + for i in result'range loop + result(i) := L xor R(i); + end loop; + return result; + end function "xor"; + + function "xor" (L : UNRESOLVED_ufixed; R : STD_ULOGIC) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (L'range); + begin + for i in result'range loop + result(i) := L(i) xor R; + end loop; + return result; + end function "xor"; + + function "xnor" (L : STD_ULOGIC; R : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (R'range); + begin + for i in result'range loop + result(i) := L xnor R(i); + end loop; + return result; + end function "xnor"; + + function "xnor" (L : UNRESOLVED_ufixed; R : STD_ULOGIC) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (L'range); + begin + for i in result'range loop + result(i) := L(i) xnor R; + end loop; + return result; + end function "xnor"; + + function "and" (L : STD_ULOGIC; R : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (R'range); + begin + for i in result'range loop + result(i) := L and R(i); + end loop; + return result; + end function "and"; + + function "and" (L : UNRESOLVED_sfixed; R : STD_ULOGIC) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (L'range); + begin + for i in result'range loop + result(i) := L(i) and R; + end loop; + return result; + end function "and"; + + function "or" (L : STD_ULOGIC; R : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (R'range); + begin + for i in result'range loop + result(i) := L or R(i); + end loop; + return result; + end function "or"; + + function "or" (L : UNRESOLVED_sfixed; R : STD_ULOGIC) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (L'range); + begin + for i in result'range loop + result(i) := L(i) or R; + end loop; + return result; + end function "or"; + + function "nand" (L : STD_ULOGIC; R : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (R'range); + begin + for i in result'range loop + result(i) := L nand R(i); + end loop; + return result; + end function "nand"; + + function "nand" (L : UNRESOLVED_sfixed; R : STD_ULOGIC) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (L'range); + begin + for i in result'range loop + result(i) := L(i) nand R; + end loop; + return result; + end function "nand"; + + function "nor" (L : STD_ULOGIC; R : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (R'range); + begin + for i in result'range loop + result(i) := L nor R(i); + end loop; + return result; + end function "nor"; + + function "nor" (L : UNRESOLVED_sfixed; R : STD_ULOGIC) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (L'range); + begin + for i in result'range loop + result(i) := L(i) nor R; + end loop; + return result; + end function "nor"; + + function "xor" (L : STD_ULOGIC; R : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (R'range); + begin + for i in result'range loop + result(i) := L xor R(i); + end loop; + return result; + end function "xor"; + + function "xor" (L : UNRESOLVED_sfixed; R : STD_ULOGIC) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (L'range); + begin + for i in result'range loop + result(i) := L(i) xor R; + end loop; + return result; + end function "xor"; + + function "xnor" (L : STD_ULOGIC; R : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (R'range); + begin + for i in result'range loop + result(i) := L xnor R(i); + end loop; + return result; + end function "xnor"; + + function "xnor" (L : UNRESOLVED_sfixed; R : STD_ULOGIC) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (L'range); + begin + for i in result'range loop + result(i) := L(i) xnor R; + end loop; + return result; + end function "xnor"; + + -- Reduction operators + function "and" (l : UNRESOLVED_ufixed) return STD_ULOGIC is + begin + return and to_sulv(l); + end function "and"; + + function "nand" (l : UNRESOLVED_ufixed) return STD_ULOGIC is + begin + return nand to_sulv(l); + end function "nand"; + + function "or" (l : UNRESOLVED_ufixed) return STD_ULOGIC is + begin + return or to_sulv(l); + end function "or"; + + function "nor" (l : UNRESOLVED_ufixed) return STD_ULOGIC is + begin + return nor to_sulv(l); + end function "nor"; + + function "xor" (l : UNRESOLVED_ufixed) return STD_ULOGIC is + begin + return xor to_sulv(l); + end function "xor"; + + function "xnor" (l : UNRESOLVED_ufixed) return STD_ULOGIC is + begin + return xnor to_sulv(l); + end function "xnor"; + + function "and" (l : UNRESOLVED_sfixed) return STD_ULOGIC is + begin + return and to_sulv(l); + end function "and"; + + function "nand" (l : UNRESOLVED_sfixed) return STD_ULOGIC is + begin + return nand to_sulv(l); + end function "nand"; + + function "or" (l : UNRESOLVED_sfixed) return STD_ULOGIC is + begin + return or to_sulv(l); + end function "or"; + + function "nor" (l : UNRESOLVED_sfixed) return STD_ULOGIC is + begin + return nor to_sulv(l); + end function "nor"; + + function "xor" (l : UNRESOLVED_sfixed) return STD_ULOGIC is + begin + return xor to_sulv(l); + end function "xor"; + + function "xnor" (l : UNRESOLVED_sfixed) return STD_ULOGIC is + begin + return xnor to_sulv(l); + end function "xnor"; + -- End reduction operators + + function "?=" (L, R : UNRESOLVED_ufixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin -- ?= + if ((L'length < 1) or (R'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?="": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv ?= rslv; + end if; + end function "?="; + + function "?/=" (L, R : UNRESOLVED_ufixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin -- ?/= + if ((L'length < 1) or (R'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?/="": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv ?/= rslv; + end if; + end function "?/="; + + function "?>" (L, R : UNRESOLVED_ufixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin -- ?> + if ((l'length < 1) or (r'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?>"": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv ?> rslv; + end if; + end function "?>"; + + function "?>=" (L, R : UNRESOLVED_ufixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin -- ?>= + if ((l'length < 1) or (r'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?>="": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv ?>= rslv; + end if; + end function "?>="; + + function "?<" (L, R : UNRESOLVED_ufixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin -- ?< + if ((l'length < 1) or (r'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?<"": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv ?< rslv; + end if; + end function "?<"; + + function "?<=" (L, R : UNRESOLVED_ufixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin -- ?<= + if ((l'length < 1) or (r'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?<="": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv ?<= rslv; + end if; + end function "?<="; + + function "?=" (L, R : UNRESOLVED_sfixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin -- ?= + if ((L'length < 1) or (R'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?="": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv ?= rslv; + end if; + end function "?="; + + function "?/=" (L, R : UNRESOLVED_sfixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin -- ?/= + if ((L'length < 1) or (R'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?/="": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv ?/= rslv; + end if; + end function "?/="; + + function "?>" (L, R : UNRESOLVED_sfixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin -- ?> + if ((l'length < 1) or (r'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?>"": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv ?> rslv; + end if; + end function "?>"; + + function "?>=" (L, R : UNRESOLVED_sfixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin -- ?>= + if ((l'length < 1) or (r'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?>="": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv ?>= rslv; + end if; + end function "?>="; + + function "?<" (L, R : UNRESOLVED_sfixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin -- ?< + if ((l'length < 1) or (r'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?<"": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv ?< rslv; + end if; + end function "?<"; + + function "?<=" (L, R : UNRESOLVED_sfixed) return STD_ULOGIC is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin -- ?<= + if ((l'length < 1) or (r'length < 1)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """?<="": null detected, returning X" + severity warning; + return 'X'; + else + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv ?<= rslv; + end if; + end function "?<="; + + -- Match function, similar to "std_match" from numeric_std + function std_match (L, R : UNRESOLVED_ufixed) return BOOLEAN is + begin + if (L'high = R'high and L'low = R'low) then + return std_match(to_sulv(L), to_sulv(R)); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "STD_MATCH: L'RANGE /= R'RANGE, returning FALSE" + severity warning; + return false; + end if; + end function std_match; + + function std_match (L, R : UNRESOLVED_sfixed) return BOOLEAN is + begin + if (L'high = R'high and L'low = R'low) then + return std_match(to_sulv(L), to_sulv(R)); + else + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "STD_MATCH: L'RANGE /= R'RANGE, returning FALSE" + severity warning; + return false; + end if; + end function std_match; + + -- compare functions + function "=" ( + l, r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """="": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """="": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv = rslv; + end function "="; + + function "=" ( + l, r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """="": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """="": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv = rslv; + end function "="; + + function "/=" ( + l, r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """/="": null argument detected, returning TRUE" + severity warning; + return true; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """/="": metavalue detected, returning TRUE" + severity warning; + return true; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv /= rslv; + end function "/="; + + function "/=" ( + l, r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """/="": null argument detected, returning TRUE" + severity warning; + return true; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """/="": metavalue detected, returning TRUE" + severity warning; + return true; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv /= rslv; + end function "/="; + + function ">" ( + l, r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """>"": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """>"": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv > rslv; + end function ">"; + + function ">" ( + l, r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """>"": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """>"": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv > rslv; + end function ">"; + + function "<" ( + l, r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """<"": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """<"": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv < rslv; + end function "<"; + + function "<" ( + l, r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """<"": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """<"": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv < rslv; + end function "<"; + + function ">=" ( + l, r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """>="": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """>="": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv >= rslv; + end function ">="; + + function ">=" ( + l, r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """>="": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """>="": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv >= rslv; + end function ">="; + + function "<=" ( + l, r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_UNSIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """<="": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """<="": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_uns (lresize); + rslv := to_uns (rresize); + return lslv <= rslv; + end function "<="; + + function "<=" ( + l, r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN + is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + variable lslv, rslv : UNRESOLVED_SIGNED (lresize'length-1 downto 0); + begin + if (l'length < 1 or r'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """<="": null argument detected, returning FALSE" + severity warning; + return false; + elsif (Is_X(l) or Is_X(r)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & """<="": metavalue detected, returning FALSE" + severity warning; + return false; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + lslv := to_s (lresize); + rslv := to_s (rresize); + return lslv <= rslv; + end function "<="; + + -- overloads of the default maximum and minimum functions + function maximum (l, r : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + begin + if (l'length < 1 or r'length < 1) then + return NAUF; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + return to_fixed(maximum(to_uns(lresize), to_uns(rresize)), + left_index, right_index); + end function maximum; + + function maximum (l, r : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + begin + if (l'length < 1 or r'length < 1) then + return NASF; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + return to_fixed(maximum(to_s(lresize), to_s(rresize)), + left_index, right_index); + end function maximum; + + function minimum (l, r : UNRESOLVED_ufixed) return UNRESOLVED_ufixed is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_ufixed (left_index downto right_index); + begin + if (l'length < 1 or r'length < 1) then + return NAUF; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + return to_fixed(minimum(to_uns(lresize), to_uns(rresize)), + left_index, right_index); + end function minimum; + + function minimum (l, r : UNRESOLVED_sfixed) return UNRESOLVED_sfixed is + constant left_index : INTEGER := maximum(l'high, r'high); + constant right_index : INTEGER := mins(l'low, r'low); + variable lresize, rresize : UNRESOLVED_sfixed (left_index downto right_index); + begin + if (l'length < 1 or r'length < 1) then + return NASF; + end if; + lresize := resize (l, left_index, right_index); + rresize := resize (r, left_index, right_index); + return to_fixed(minimum(to_s(lresize), to_s(rresize)), + left_index, right_index); + end function minimum; + + function to_ufixed ( + arg : NATURAL; -- integer + constant left_index : INTEGER; -- left index (high index) + constant right_index : INTEGER := 0; -- right index + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_ufixed + is + constant fw : INTEGER := mins (right_index, right_index); -- catch literals + variable result : UNRESOLVED_ufixed (left_index downto fw); + variable sresult : UNRESOLVED_ufixed (left_index downto 0) := + (others => '0'); -- integer portion + variable argx : NATURAL; -- internal version of arg + begin + if (result'length < 1) then + return NAUF; + end if; + if arg /= 0 then + argx := arg; + for I in 0 to sresult'left loop + if (argx mod 2) = 0 then + sresult(I) := '0'; + else + sresult(I) := '1'; + end if; + argx := argx/2; + end loop; + if argx /= 0 then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "TO_UFIXED(NATURAL): vector truncated" + severity warning; + if overflow_style = fixed_saturate then + return saturate (left_index, right_index); + end if; + end if; + result := resize (arg => sresult, + left_index => left_index, + right_index => right_index, + round_style => round_style, + overflow_style => overflow_style); + else + result := (others => '0'); + end if; + return result; + end function to_ufixed; + + function to_sfixed ( + arg : INTEGER; -- integer + constant left_index : INTEGER; -- left index (high index) + constant right_index : INTEGER := 0; -- right index + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_sfixed + is + constant fw : INTEGER := mins (right_index, right_index); -- catch literals + variable result : UNRESOLVED_sfixed (left_index downto fw); + variable sresult : UNRESOLVED_sfixed (left_index downto 0) := + (others => '0'); -- integer portion + variable argx : INTEGER; -- internal version of arg + variable sign : STD_ULOGIC; -- sign of input + begin + if (result'length < 1) then -- null range + return NASF; + end if; + if arg /= 0 then + if (arg < 0) then + sign := '1'; + argx := -(arg + 1); + else + sign := '0'; + argx := arg; + end if; + for I in 0 to sresult'left loop + if (argx mod 2) = 0 then + sresult(I) := sign; + else + sresult(I) := not sign; + end if; + argx := argx/2; + end loop; + if argx /= 0 or left_index < 0 or sign /= sresult(sresult'left) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "TO_SFIXED(INTEGER): vector truncated" + severity warning; + if overflow_style = fixed_saturate then -- saturate + if arg < 0 then + result := not saturate (result'high, result'low); -- underflow + else + result := saturate (result'high, result'low); -- overflow + end if; + return result; + end if; + end if; + result := resize (arg => sresult, + left_index => left_index, + right_index => right_index, + round_style => round_style, + overflow_style => overflow_style); + else + result := (others => '0'); + end if; + return result; + end function to_sfixed; + + function to_ufixed ( + arg : REAL; -- real + constant left_index : INTEGER; -- left index (high index) + constant right_index : INTEGER; -- right index + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) -- # of guard bits + return UNRESOLVED_ufixed + is + constant fw : INTEGER := mins (right_index, right_index); -- catch literals + variable result : UNRESOLVED_ufixed (left_index downto fw) := + (others => '0'); + variable Xresult : UNRESOLVED_ufixed (left_index downto + fw-guard_bits) := + (others => '0'); + variable presult : REAL; + begin + -- If negative or null range, return. + if (left_index < fw) then + return NAUF; + end if; + if (arg < 0.0) then + report fixed_generic_pkg'instance_name + & "TO_UFIXED: Negative argument passed " + & REAL'image(arg) severity error; + return result; + end if; + presult := arg; + if presult >= (2.0**(left_index+1)) then + assert NO_WARNING report fixed_generic_pkg'instance_name + & "TO_UFIXED(REAL): vector truncated" + severity warning; + if overflow_style = fixed_wrap then + presult := presult mod (2.0**(left_index+1)); -- wrap + else + return saturate (result'high, result'low); + end if; + end if; + for i in Xresult'range loop + if presult >= 2.0**i then + Xresult(i) := '1'; + presult := presult - 2.0**i; + else + Xresult(i) := '0'; + end if; + end loop; + if guard_bits > 0 and round_style = fixed_round then + result := round_fixed (arg => Xresult (left_index + downto right_index), + remainder => Xresult (right_index-1 downto + right_index-guard_bits), + overflow_style => overflow_style); + else + result := Xresult (result'range); + end if; + return result; + end function to_ufixed; + + function to_sfixed ( + arg : REAL; -- real + constant left_index : INTEGER; -- left index (high index) + constant right_index : INTEGER; -- right index + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) -- # of guard bits + return UNRESOLVED_sfixed + is + constant fw : INTEGER := mins (right_index, right_index); -- catch literals + variable result : UNRESOLVED_sfixed (left_index downto fw) := + (others => '0'); + variable Xresult : UNRESOLVED_sfixed (left_index+1 downto fw-guard_bits) := + (others => '0'); + variable presult : REAL; + begin + if (left_index < fw) then -- null range + return NASF; + end if; + if (arg >= (2.0**left_index) or arg < -(2.0**left_index)) then + assert NO_WARNING report fixed_generic_pkg'instance_name + & "TO_SFIXED(REAL): vector truncated" + severity warning; + if overflow_style = fixed_saturate then + if arg < 0.0 then -- saturate + result := not saturate (result'high, result'low); -- underflow + else + result := saturate (result'high, result'low); -- overflow + end if; + return result; + else + presult := abs(arg) mod (2.0**(left_index+1)); -- wrap + end if; + else + presult := abs(arg); + end if; + for i in Xresult'range loop + if presult >= 2.0**i then + Xresult(i) := '1'; + presult := presult - 2.0**i; + else + Xresult(i) := '0'; + end if; + end loop; + if arg < 0.0 then + Xresult := to_fixed(-to_s(Xresult), Xresult'high, Xresult'low); + end if; + if guard_bits > 0 and round_style = fixed_round then + result := round_fixed (arg => Xresult (left_index + downto right_index), + remainder => Xresult (right_index-1 downto + right_index-guard_bits), + overflow_style => overflow_style); + else + result := Xresult (result'range); + end if; + return result; + end function to_sfixed; + + function to_ufixed ( + arg : UNRESOLVED_UNSIGNED; -- unsigned + constant left_index : INTEGER; -- left index (high index) + constant right_index : INTEGER := 0; -- right index + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_ufixed + is + constant ARG_LEFT : INTEGER := ARG'length-1; + alias XARG : UNRESOLVED_UNSIGNED(ARG_LEFT downto 0) is ARG; + variable result : UNRESOLVED_ufixed (left_index downto right_index); + begin + if arg'length < 1 or (left_index < right_index) then + return NAUF; + end if; + result := resize (arg => UNRESOLVED_ufixed (XARG), + left_index => left_index, + right_index => right_index, + round_style => round_style, + overflow_style => overflow_style); + return result; + end function to_ufixed; + + -- converted version + function to_ufixed ( + arg : UNRESOLVED_UNSIGNED) -- unsigned + return UNRESOLVED_ufixed + is + constant ARG_LEFT : INTEGER := ARG'length-1; + alias XARG : UNRESOLVED_UNSIGNED(ARG_LEFT downto 0) is ARG; + begin + if arg'length < 1 then + return NAUF; + end if; + return UNRESOLVED_ufixed(xarg); + end function to_ufixed; + + function to_sfixed ( + arg : UNRESOLVED_SIGNED; -- signed + constant left_index : INTEGER; -- left index (high index) + constant right_index : INTEGER := 0; -- right index + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_sfixed + is + constant ARG_LEFT : INTEGER := ARG'length-1; + alias XARG : UNRESOLVED_SIGNED(ARG_LEFT downto 0) is ARG; + variable result : UNRESOLVED_sfixed (left_index downto right_index); + begin + if arg'length < 1 or (left_index < right_index) then + return NASF; + end if; + result := resize (arg => UNRESOLVED_sfixed (XARG), + left_index => left_index, + right_index => right_index, + round_style => round_style, + overflow_style => overflow_style); + return result; + end function to_sfixed; + + -- converted version + function to_sfixed ( + arg : UNRESOLVED_SIGNED) -- signed + return UNRESOLVED_sfixed + is + constant ARG_LEFT : INTEGER := ARG'length-1; + alias XARG : UNRESOLVED_SIGNED(ARG_LEFT downto 0) is ARG; + begin + if arg'length < 1 then + return NASF; + end if; + return UNRESOLVED_sfixed(xarg); + end function to_sfixed; + + function to_sfixed (arg : UNRESOLVED_ufixed) return UNRESOLVED_sfixed is + variable result : UNRESOLVED_sfixed (arg'high+1 downto arg'low); + begin + if arg'length < 1 then + return NASF; + end if; + result (arg'high downto arg'low) := UNRESOLVED_sfixed(cleanvec(arg)); + result (arg'high+1) := '0'; + return result; + end function to_sfixed; + + -- Because of the fairly complicated sizing rules in the fixed point + -- packages these functions are provided to compute the result ranges + -- Example: + -- signal uf1 : ufixed (3 downto -3); + -- signal uf2 : ufixed (4 downto -2); + -- signal uf1multuf2 : ufixed (ufixed_high (3, -3, '*', 4, -2) downto + -- ufixed_low (3, -3, '*', 4, -2)); + -- uf1multuf2 <= uf1 * uf2; + -- Valid characters: '+', '-', '*', '/', 'r' or 'R' (rem), 'm' or 'M' (mod), + -- '1' (reciprocal), 'A', 'a' (abs), 'N', 'n' (-sfixed) + function ufixed_high (left_index, right_index : INTEGER; + operation : CHARACTER := 'X'; + left_index2, right_index2 : INTEGER := 0) + return INTEGER is + begin + case operation is + when '+'| '-' => return maximum (left_index, left_index2) + 1; + when '*' => return left_index + left_index2 + 1; + when '/' => return left_index - right_index2; + when '1' => return -right_index; -- reciprocal + when 'R'|'r' => return mins (left_index, left_index2); -- "rem" + when 'M'|'m' => return mins (left_index, left_index2); -- "mod" + when others => return left_index; -- For abs and default + end case; + end function ufixed_high; + + function ufixed_low (left_index, right_index : INTEGER; + operation : CHARACTER := 'X'; + left_index2, right_index2 : INTEGER := 0) + return INTEGER is + begin + case operation is + when '+'| '-' => return mins (right_index, right_index2); + when '*' => return right_index + right_index2; + when '/' => return right_index - left_index2 - 1; + when '1' => return -left_index - 1; -- reciprocal + when 'R'|'r' => return mins (right_index, right_index2); -- "rem" + when 'M'|'m' => return mins (right_index, right_index2); -- "mod" + when others => return right_index; -- for abs and default + end case; + end function ufixed_low; + + function sfixed_high (left_index, right_index : INTEGER; + operation : CHARACTER := 'X'; + left_index2, right_index2 : INTEGER := 0) + return INTEGER is + begin + case operation is + when '+'| '-' => return maximum (left_index, left_index2) + 1; + when '*' => return left_index + left_index2 + 1; + when '/' => return left_index - right_index2 + 1; + when '1' => return -right_index + 1; -- reciprocal + when 'R'|'r' => return mins (left_index, left_index2); -- "rem" + when 'M'|'m' => return left_index2; -- "mod" + when 'A'|'a' => return left_index + 1; -- "abs" + when 'N'|'n' => return left_index + 1; -- -sfixed + when others => return left_index; + end case; + end function sfixed_high; + + function sfixed_low (left_index, right_index : INTEGER; + operation : CHARACTER := 'X'; + left_index2, right_index2 : INTEGER := 0) + return INTEGER is + begin + case operation is + when '+'| '-' => return mins (right_index, right_index2); + when '*' => return right_index + right_index2; + when '/' => return right_index - left_index2; + when '1' => return -left_index; -- reciprocal + when 'R'|'r' => return mins (right_index, right_index2); -- "rem" + when 'M'|'m' => return mins (right_index, right_index2); -- "mod" + when others => return right_index; -- default for abs, neg and default + end case; + end function sfixed_low; + + -- Same as above, but using the "size_res" input only for their ranges: + -- signal uf1multuf2 : ufixed (ufixed_high (uf1, '*', uf2) downto + -- ufixed_low (uf1, '*', uf2)); + -- uf1multuf2 <= uf1 * uf2; + function ufixed_high (size_res : UNRESOLVED_ufixed; + operation : CHARACTER := 'X'; + size_res2 : UNRESOLVED_ufixed) + return INTEGER is + begin + return ufixed_high (left_index => size_res'high, + right_index => size_res'low, + operation => operation, + left_index2 => size_res2'high, + right_index2 => size_res2'low); + end function ufixed_high; + + function ufixed_low (size_res : UNRESOLVED_ufixed; + operation : CHARACTER := 'X'; + size_res2 : UNRESOLVED_ufixed) + return INTEGER is + begin + return ufixed_low (left_index => size_res'high, + right_index => size_res'low, + operation => operation, + left_index2 => size_res2'high, + right_index2 => size_res2'low); + end function ufixed_low; + + function sfixed_high (size_res : UNRESOLVED_sfixed; + operation : CHARACTER := 'X'; + size_res2 : UNRESOLVED_sfixed) + return INTEGER is + begin + return sfixed_high (left_index => size_res'high, + right_index => size_res'low, + operation => operation, + left_index2 => size_res2'high, + right_index2 => size_res2'low); + end function sfixed_high; + + function sfixed_low (size_res : UNRESOLVED_sfixed; + operation : CHARACTER := 'X'; + size_res2 : UNRESOLVED_sfixed) + return INTEGER is + begin + return sfixed_low (left_index => size_res'high, + right_index => size_res'low, + operation => operation, + left_index2 => size_res2'high, + right_index2 => size_res2'low); + end function sfixed_low; + + -- purpose: returns a saturated number + function saturate ( + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_ufixed + is + constant sat : UNRESOLVED_ufixed (left_index downto right_index) := + (others => '1'); + begin + return sat; + end function saturate; + + -- purpose: returns a saturated number + function saturate ( + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_sfixed + is + variable sat : UNRESOLVED_sfixed (left_index downto right_index) := + (others => '1'); + begin + -- saturate positive, to saturate negative, just do "not saturate()" + sat (left_index) := '0'; + return sat; + end function saturate; + + function saturate ( + size_res : UNRESOLVED_ufixed) -- only the size of this is used + return UNRESOLVED_ufixed is + begin + return saturate (size_res'high, size_res'low); + end function saturate; + + function saturate ( + size_res : UNRESOLVED_sfixed) -- only the size of this is used + return UNRESOLVED_sfixed is + begin + return saturate (size_res'high, size_res'low); + end function saturate; + + -- As a concession to those who use a graphical DSP environment, + -- these functions take parameters in those tools format and create + -- fixed point numbers. These functions are designed to convert from + -- a std_logic_vector to the VHDL fixed point format using the conventions + -- of these packages. In a pure VHDL environment you should use the + -- "to_ufixed" and "to_sfixed" routines. + -- Unsigned fixed point + function to_UFix ( + arg : STD_ULOGIC_VECTOR; + width : NATURAL; -- width of vector + fraction : NATURAL) -- width of fraction + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (width-fraction-1 downto -fraction); + begin + if (arg'length /= result'length) then + report fixed_generic_pkg'instance_name + & "TO_UFIX (STD_ULOGIC_VECTOR) " + & "Vector lengths do not match. Input length is " + & INTEGER'image(arg'length) & " and output will be " + & INTEGER'image(result'length) & " wide." + severity error; + return NAUF; + else + result := to_ufixed (arg, result'high, result'low); + return result; + end if; + end function to_UFix; + + -- signed fixed point + function to_SFix ( + arg : STD_ULOGIC_VECTOR; + width : NATURAL; -- width of vector + fraction : NATURAL) -- width of fraction + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (width-fraction-1 downto -fraction); + begin + if (arg'length /= result'length) then + report fixed_generic_pkg'instance_name + & "TO_SFIX (STD_ULOGIC_VECTOR) " + & "Vector lengths do not match. Input length is " + & INTEGER'image(arg'length) & " and output will be " + & INTEGER'image(result'length) & " wide." + severity error; + return NASF; + else + result := to_sfixed (arg, result'high, result'low); + return result; + end if; + end function to_SFix; + + -- finding the bounds of a number. These functions can be used like this: + -- signal xxx : ufixed (7 downto -3); + -- -- Which is the same as "ufixed (UFix_high (11,3) downto UFix_low(11,3))" + -- signal yyy : ufixed (UFix_high (11, 3, "+", 11, 3) + -- downto UFix_low(11, 3, "+", 11, 3)); + -- Where "11" is the width of xxx (xxx'length), + -- and 3 is the lower bound (abs (xxx'low)) + -- In a pure VHDL environment use "ufixed_high" and "ufixed_low" + function ufix_high ( + width, fraction : NATURAL; + operation : CHARACTER := 'X'; + width2, fraction2 : NATURAL := 0) + return INTEGER is + begin + return ufixed_high (left_index => width - 1 - fraction, + right_index => -fraction, + operation => operation, + left_index2 => width2 - 1 - fraction2, + right_index2 => -fraction2); + end function ufix_high; + + function ufix_low ( + width, fraction : NATURAL; + operation : CHARACTER := 'X'; + width2, fraction2 : NATURAL := 0) + return INTEGER is + begin + return ufixed_low (left_index => width - 1 - fraction, + right_index => -fraction, + operation => operation, + left_index2 => width2 - 1 - fraction2, + right_index2 => -fraction2); + end function ufix_low; + + function sfix_high ( + width, fraction : NATURAL; + operation : CHARACTER := 'X'; + width2, fraction2 : NATURAL := 0) + return INTEGER is + begin + return sfixed_high (left_index => width - fraction, + right_index => -fraction, + operation => operation, + left_index2 => width2 - fraction2, + right_index2 => -fraction2); + end function sfix_high; + + function sfix_low ( + width, fraction : NATURAL; + operation : CHARACTER := 'X'; + width2, fraction2 : NATURAL := 0) + return INTEGER is + begin + return sfixed_low (left_index => width - fraction, + right_index => -fraction, + operation => operation, + left_index2 => width2 - fraction2, + right_index2 => -fraction2); + end function sfix_low; + + function to_unsigned ( + arg : UNRESOLVED_ufixed; -- ufixed point input + constant size : NATURAL; -- length of output + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_UNSIGNED is + begin + return to_uns(resize (arg => arg, + left_index => size-1, + right_index => 0, + round_style => round_style, + overflow_style => overflow_style)); + end function to_unsigned; + + function to_unsigned ( + arg : UNRESOLVED_ufixed; -- ufixed point input + size_res : UNRESOLVED_UNSIGNED; -- length of output + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_UNSIGNED is + begin + return to_unsigned (arg => arg, + size => size_res'length, + round_style => round_style, + overflow_style => overflow_style); + end function to_unsigned; + + function to_signed ( + arg : UNRESOLVED_sfixed; -- sfixed point input + constant size : NATURAL; -- length of output + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_SIGNED is + begin + return to_s(resize (arg => arg, + left_index => size-1, + right_index => 0, + round_style => round_style, + overflow_style => overflow_style)); + end function to_signed; + + function to_signed ( + arg : UNRESOLVED_sfixed; -- sfixed point input + size_res : UNRESOLVED_SIGNED; -- used for length of output + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_SIGNED is + begin + return to_signed (arg => arg, + size => size_res'length, + round_style => round_style, + overflow_style => overflow_style); + end function to_signed; + + function to_real ( + arg : UNRESOLVED_ufixed) -- ufixed point input + return REAL + is + constant left_index : INTEGER := arg'high; + constant right_index : INTEGER := arg'low; + variable result : REAL; -- result + variable arg_int : UNRESOLVED_ufixed (left_index downto right_index); + begin + if (arg'length < 1) then + return 0.0; + end if; + arg_int := to_x01(cleanvec(arg)); + if (Is_X(arg_int)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "TO_REAL (ufixed): metavalue detected, returning 0.0" + severity warning; + return 0.0; + end if; + result := 0.0; + for i in arg_int'range loop + if (arg_int(i) = '1') then + result := result + (2.0**i); + end if; + end loop; + return result; + end function to_real; + + function to_real ( + arg : UNRESOLVED_sfixed) -- ufixed point input + return REAL + is + constant left_index : INTEGER := arg'high; + constant right_index : INTEGER := arg'low; + variable result : REAL; -- result + variable arg_int : UNRESOLVED_sfixed (left_index downto right_index); + -- unsigned version of argument + variable arg_uns : UNRESOLVED_ufixed (left_index downto right_index); + -- absolute of argument + begin + if (arg'length < 1) then + return 0.0; + end if; + arg_int := to_x01(cleanvec(arg)); + if (Is_X(arg_int)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "TO_REAL (sfixed): metavalue detected, returning 0.0" + severity warning; + return 0.0; + end if; + arg_uns := to_ufixed (arg_int); + result := to_real (arg_uns); + if (arg_int(arg_int'high) = '1') then + result := -result; + end if; + return result; + end function to_real; + + function to_integer ( + arg : UNRESOLVED_ufixed; -- fixed point input + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return NATURAL + is + constant left_index : INTEGER := arg'high; + variable arg_uns : UNRESOLVED_UNSIGNED (left_index+1 downto 0) + := (others => '0'); + begin + if (arg'length < 1) then + return 0; + end if; + if (Is_X (arg)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "TO_INTEGER (ufixed): metavalue detected, returning 0" + severity warning; + return 0; + end if; + if (left_index < -1) then + return 0; + end if; + arg_uns := to_uns(resize (arg => arg, + left_index => arg_uns'high, + right_index => 0, + round_style => round_style, + overflow_style => overflow_style)); + return to_integer (arg_uns); + end function to_integer; + + function to_integer ( + arg : UNRESOLVED_sfixed; -- fixed point input + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return INTEGER + is + constant left_index : INTEGER := arg'high; + constant right_index : INTEGER := arg'low; + variable arg_s : UNRESOLVED_SIGNED (left_index+1 downto 0); + begin + if (arg'length < 1) then + return 0; + end if; + if (Is_X (arg)) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "TO_INTEGER (sfixed): metavalue detected, returning 0" + severity warning; + return 0; + end if; + if (left_index < -1) then + return 0; + end if; + arg_s := to_s(resize (arg => arg, + left_index => arg_s'high, + right_index => 0, + round_style => round_style, + overflow_style => overflow_style)); + return to_integer (arg_s); + end function to_integer; + + function to_01 ( + s : UNRESOLVED_ufixed; -- ufixed point input + constant XMAP : STD_ULOGIC := '0') -- Map x to + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (s'range); -- result + begin + if (s'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "TO_01(ufixed): null detected, returning NULL" + severity warning; + return NAUF; + end if; + return to_fixed (to_01(to_uns(s), XMAP), s'high, s'low); + end function to_01; + + function to_01 ( + s : UNRESOLVED_sfixed; -- sfixed point input + constant XMAP : STD_ULOGIC := '0') -- Map x to + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (s'range); + begin + if (s'length < 1) then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "TO_01(sfixed): null detected, returning NULL" + severity warning; + return NASF; + end if; + return to_fixed (to_01(to_s(s), XMAP), s'high, s'low); + end function to_01; + + function Is_X ( + arg : UNRESOLVED_ufixed) + return BOOLEAN + is + variable argslv : STD_ULOGIC_VECTOR (arg'length-1 downto 0); -- slv + begin + argslv := to_sulv(arg); + return Is_X (argslv); + end function Is_X; + + function Is_X ( + arg : UNRESOLVED_sfixed) + return BOOLEAN + is + variable argslv : STD_ULOGIC_VECTOR (arg'length-1 downto 0); -- slv + begin + argslv := to_sulv(arg); + return Is_X (argslv); + end function Is_X; + + function To_X01 ( + arg : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed is + begin + return to_ufixed (To_X01(to_sulv(arg)), arg'high, arg'low); + end function To_X01; + + function to_X01 ( + arg : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return to_sfixed (To_X01(to_sulv(arg)), arg'high, arg'low); + end function To_X01; + + function To_X01Z ( + arg : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed is + begin + return to_ufixed (To_X01Z(to_sulv(arg)), arg'high, arg'low); + end function To_X01Z; + + function to_X01Z ( + arg : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return to_sfixed (To_X01Z(to_sulv(arg)), arg'high, arg'low); + end function To_X01Z; + + function To_UX01 ( + arg : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed is + begin + return to_ufixed (To_UX01(to_sulv(arg)), arg'high, arg'low); + end function To_UX01; + + function to_UX01 ( + arg : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return to_sfixed (To_UX01(to_sulv(arg)), arg'high, arg'low); + end function To_UX01; + + function resize ( + arg : UNRESOLVED_ufixed; -- input + constant left_index : INTEGER; -- integer portion + constant right_index : INTEGER; -- size of fraction + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_ufixed + is + constant arghigh : INTEGER := maximum (arg'high, arg'low); + constant arglow : INTEGER := mine (arg'high, arg'low); + variable invec : UNRESOLVED_ufixed (arghigh downto arglow); + variable result : UNRESOLVED_ufixed(left_index downto right_index) := + (others => '0'); + variable needs_rounding : BOOLEAN := false; + begin -- resize + if (arg'length < 1) or (result'length < 1) then + return NAUF; + elsif (invec'length < 1) then + return result; -- string literal value + else + invec := cleanvec(arg); + if (right_index > arghigh) then -- return top zeros + needs_rounding := (round_style = fixed_round) and + (right_index = arghigh+1); + elsif (left_index < arglow) then -- return overflow + if (overflow_style = fixed_saturate) and + (or(to_sulv(invec)) = '1') then + result := saturate (result'high, result'low); -- saturate + end if; + elsif (arghigh > left_index) then + -- wrap or saturate? + if (overflow_style = fixed_saturate and + or (to_sulv(invec(arghigh downto left_index+1))) = '1') + then + result := saturate (result'high, result'low); -- saturate + else + if (arglow >= right_index) then + result (left_index downto arglow) := + invec(left_index downto arglow); + else + result (left_index downto right_index) := + invec (left_index downto right_index); + needs_rounding := (round_style = fixed_round); -- round + end if; + end if; + else -- arghigh <= integer width + if (arglow >= right_index) then + result (arghigh downto arglow) := invec; + else + result (arghigh downto right_index) := + invec (arghigh downto right_index); + needs_rounding := (round_style = fixed_round); -- round + end if; + end if; + -- Round result + if needs_rounding then + result := round_fixed (arg => result, + remainder => invec (right_index-1 + downto arglow), + overflow_style => overflow_style); + end if; + return result; + end if; + end function resize; + + function resize ( + arg : UNRESOLVED_sfixed; -- input + constant left_index : INTEGER; -- integer portion + constant right_index : INTEGER; -- size of fraction + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_sfixed + is + constant arghigh : INTEGER := maximum (arg'high, arg'low); + constant arglow : INTEGER := mine (arg'high, arg'low); + variable invec : UNRESOLVED_sfixed (arghigh downto arglow); + variable result : UNRESOLVED_sfixed(left_index downto right_index) := + (others => '0'); + variable reduced : STD_ULOGIC; + variable needs_rounding : BOOLEAN := false; -- rounding + begin -- resize + if (arg'length < 1) or (result'length < 1) then + return NASF; + elsif (invec'length < 1) then + return result; -- string literal value + else + invec := cleanvec(arg); + if (right_index > arghigh) then -- return top zeros + if (arg'low /= INTEGER'low) then -- check for a literal + result := (others => arg(arghigh)); -- sign extend + end if; + needs_rounding := (round_style = fixed_round) and + (right_index = arghigh+1); + elsif (left_index < arglow) then -- return overflow + if (overflow_style = fixed_saturate) then + reduced := or (to_sulv(invec)); + if (reduced = '1') then + if (invec(arghigh) = '0') then + -- saturate POSITIVE + result := saturate (result'high, result'low); + else + -- saturate negative + result := not saturate (result'high, result'low); + end if; + -- else return 0 (input was 0) + end if; + -- else return 0 (wrap) + end if; + elsif (arghigh > left_index) then + if (invec(arghigh) = '0') then + reduced := or (to_sulv(invec(arghigh-1 downto + left_index))); + if overflow_style = fixed_saturate and reduced = '1' then + -- saturate positive + result := saturate (result'high, result'low); + else + if (right_index > arglow) then + result := invec (left_index downto right_index); + needs_rounding := (round_style = fixed_round); + else + result (left_index downto arglow) := + invec (left_index downto arglow); + end if; + end if; + else + reduced := and (to_sulv(invec(arghigh-1 downto + left_index))); + if overflow_style = fixed_saturate and reduced = '0' then + result := not saturate (result'high, result'low); + else + if (right_index > arglow) then + result := invec (left_index downto right_index); + needs_rounding := (round_style = fixed_round); + else + result (left_index downto arglow) := + invec (left_index downto arglow); + end if; + end if; + end if; + else -- arghigh <= integer width + if (arglow >= right_index) then + result (arghigh downto arglow) := invec; + else + result (arghigh downto right_index) := + invec (arghigh downto right_index); + needs_rounding := (round_style = fixed_round); -- round + end if; + if (left_index > arghigh) then -- sign extend + result(left_index downto arghigh+1) := (others => invec(arghigh)); + end if; + end if; + -- Round result + if (needs_rounding) then + result := round_fixed (arg => result, + remainder => invec (right_index-1 + downto arglow), + overflow_style => overflow_style); + end if; + return result; + end if; + end function resize; + + -- size_res functions + -- These functions compute the size from a passed variable named "size_res" + -- The only part of this variable used it it's size, it is never passed + -- to a lower level routine. + function to_ufixed ( + arg : STD_ULOGIC_VECTOR; -- shifted vector + size_res : UNRESOLVED_ufixed) -- for size only + return UNRESOLVED_ufixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_ufixed (size_res'left downto fw); + begin + if (result'length < 1 or arg'length < 1) then + return NAUF; + else + result := to_ufixed (arg => arg, + left_index => size_res'high, + right_index => size_res'low); + return result; + end if; + end function to_ufixed; + + function to_sfixed ( + arg : STD_ULOGIC_VECTOR; -- shifted vector + size_res : UNRESOLVED_sfixed) -- for size only + return UNRESOLVED_sfixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_sfixed (size_res'left downto fw); + begin + if (result'length < 1 or arg'length < 1) then + return NASF; + else + result := to_sfixed (arg => arg, + left_index => size_res'high, + right_index => size_res'low); + return result; + end if; + end function to_sfixed; + + function to_ufixed ( + arg : NATURAL; -- integer + size_res : UNRESOLVED_ufixed; -- for size only + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_ufixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_ufixed (size_res'left downto fw); + begin + if (result'length < 1) then + return NAUF; + else + result := to_ufixed (arg => arg, + left_index => size_res'high, + right_index => size_res'low, + round_style => round_style, + overflow_style => overflow_style); + return result; + end if; + end function to_ufixed; + + function to_sfixed ( + arg : INTEGER; -- integer + size_res : UNRESOLVED_sfixed; -- for size only + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_sfixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_sfixed (size_res'left downto fw); + begin + if (result'length < 1) then + return NASF; + else + result := to_sfixed (arg => arg, + left_index => size_res'high, + right_index => size_res'low, + round_style => round_style, + overflow_style => overflow_style); + return result; + end if; + end function to_sfixed; + + function to_ufixed ( + arg : REAL; -- real + size_res : UNRESOLVED_ufixed; -- for size only + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) -- # of guard bits + return UNRESOLVED_ufixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_ufixed (size_res'left downto fw); + begin + if (result'length < 1) then + return NAUF; + else + result := to_ufixed (arg => arg, + left_index => size_res'high, + right_index => size_res'low, + guard_bits => guard_bits, + round_style => round_style, + overflow_style => overflow_style); + return result; + end if; + end function to_ufixed; + + function to_sfixed ( + arg : REAL; -- real + size_res : UNRESOLVED_sfixed; -- for size only + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style; + constant guard_bits : NATURAL := fixed_guard_bits) -- # of guard bits + return UNRESOLVED_sfixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_sfixed (size_res'left downto fw); + begin + if (result'length < 1) then + return NASF; + else + result := to_sfixed (arg => arg, + left_index => size_res'high, + right_index => size_res'low, + guard_bits => guard_bits, + round_style => round_style, + overflow_style => overflow_style); + return result; + end if; + end function to_sfixed; + + function to_ufixed ( + arg : UNRESOLVED_UNSIGNED; -- unsigned + size_res : UNRESOLVED_ufixed; -- for size only + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_ufixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_ufixed (size_res'left downto fw); + begin + if (result'length < 1 or arg'length < 1) then + return NAUF; + else + result := to_ufixed (arg => arg, + left_index => size_res'high, + right_index => size_res'low, + round_style => round_style, + overflow_style => overflow_style); + return result; + end if; + end function to_ufixed; + + function to_sfixed ( + arg : UNRESOLVED_SIGNED; -- signed + size_res : UNRESOLVED_sfixed; -- for size only + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_sfixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_sfixed (size_res'left downto fw); + begin + if (result'length < 1 or arg'length < 1) then + return NASF; + else + result := to_sfixed (arg => arg, + left_index => size_res'high, + right_index => size_res'low, + round_style => round_style, + overflow_style => overflow_style); + return result; + end if; + end function to_sfixed; + + function resize ( + arg : UNRESOLVED_ufixed; -- input + size_res : UNRESOLVED_ufixed; -- for size only + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_ufixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_ufixed (size_res'high downto fw); + begin + if (result'length < 1 or arg'length < 1) then + return NAUF; + else + result := resize (arg => arg, + left_index => size_res'high, + right_index => size_res'low, + round_style => round_style, + overflow_style => overflow_style); + return result; + end if; + end function resize; + + function resize ( + arg : UNRESOLVED_sfixed; -- input + size_res : UNRESOLVED_sfixed; -- for size only + constant overflow_style : fixed_overflow_style_type := fixed_overflow_style; + constant round_style : fixed_round_style_type := fixed_round_style) + return UNRESOLVED_sfixed + is + constant fw : INTEGER := mine (size_res'low, size_res'low); -- catch literals + variable result : UNRESOLVED_sfixed (size_res'high downto fw); + begin + if (result'length < 1 or arg'length < 1) then + return NASF; + else + result := resize (arg => arg, + left_index => size_res'high, + right_index => size_res'low, + round_style => round_style, + overflow_style => overflow_style); + return result; + end if; + end function resize; + + -- Overloaded math functions for real + function "+" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : REAL) + return UNRESOLVED_ufixed is + begin + return (l + to_ufixed (r, l'high, l'low)); + end function "+"; + + function "+" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, r'low) + r); + end function "+"; + + function "+" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : REAL) + return UNRESOLVED_sfixed is + begin + return (l + to_sfixed (r, l'high, l'low)); + end function "+"; + + function "+" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, r'low) + r); + end function "+"; + + function "-" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : REAL) + return UNRESOLVED_ufixed is + begin + return (l - to_ufixed (r, l'high, l'low)); + end function "-"; + + function "-" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, r'low) - r); + end function "-"; + + function "-" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : REAL) + return UNRESOLVED_sfixed is + begin + return (l - to_sfixed (r, l'high, l'low)); + end function "-"; + + function "-" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, r'low) - r); + end function "-"; + + function "*" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : REAL) + return UNRESOLVED_ufixed is + begin + return (l * to_ufixed (r, l'high, l'low)); + end function "*"; + + function "*" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, r'low) * r); + end function "*"; + + function "*" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : REAL) + return UNRESOLVED_sfixed is + begin + return (l * to_sfixed (r, l'high, l'low)); + end function "*"; + + function "*" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, r'low) * r); + end function "*"; + + function "/" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : REAL) + return UNRESOLVED_ufixed is + begin + return (l / to_ufixed (r, l'high, l'low)); + end function "/"; + + function "/" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, r'low) / r); + end function "/"; + + function "/" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : REAL) + return UNRESOLVED_sfixed is + begin + return (l / to_sfixed (r, l'high, l'low)); + end function "/"; + + function "/" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, r'low) / r); + end function "/"; + + function "rem" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : REAL) + return UNRESOLVED_ufixed is + begin + return (l rem to_ufixed (r, l'high, l'low)); + end function "rem"; + + function "rem" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, r'low) rem r); + end function "rem"; + + function "rem" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : REAL) + return UNRESOLVED_sfixed is + begin + return (l rem to_sfixed (r, l'high, l'low)); + end function "rem"; + + function "rem" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, r'low) rem r); + end function "rem"; + + function "mod" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : REAL) + return UNRESOLVED_ufixed is + begin + return (l mod to_ufixed (r, l'high, l'low)); + end function "mod"; + + function "mod" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, r'low) mod r); + end function "mod"; + + function "mod" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : REAL) + return UNRESOLVED_sfixed is + begin + return (l mod to_sfixed (r, l'high, l'low)); + end function "mod"; + + function "mod" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, r'low) mod r); + end function "mod"; + + -- Overloaded math functions for integers + function "+" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : NATURAL) + return UNRESOLVED_ufixed is + begin + return (l + to_ufixed (r, l'high, 0)); + end function "+"; + + function "+" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, 0) + r); + end function "+"; + + function "+" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : INTEGER) + return UNRESOLVED_sfixed is + begin + return (l + to_sfixed (r, l'high, 0)); + end function "+"; + + function "+" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, 0) + r); + end function "+"; + + -- Overloaded functions + function "-" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : NATURAL) + return UNRESOLVED_ufixed is + begin + return (l - to_ufixed (r, l'high, 0)); + end function "-"; + + function "-" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, 0) - r); + end function "-"; + + function "-" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : INTEGER) + return UNRESOLVED_sfixed is + begin + return (l - to_sfixed (r, l'high, 0)); + end function "-"; + + function "-" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, 0) - r); + end function "-"; + + -- Overloaded functions + function "*" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : NATURAL) + return UNRESOLVED_ufixed is + begin + return (l * to_ufixed (r, l'high, 0)); + end function "*"; + + function "*" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, 0) * r); + end function "*"; + + function "*" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : INTEGER) + return UNRESOLVED_sfixed is + begin + return (l * to_sfixed (r, l'high, 0)); + end function "*"; + + function "*" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, 0) * r); + end function "*"; + + -- Overloaded functions + function "/" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : NATURAL) + return UNRESOLVED_ufixed is + begin + return (l / to_ufixed (r, l'high, 0)); + end function "/"; + + function "/" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, 0) / r); + end function "/"; + + function "/" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : INTEGER) + return UNRESOLVED_sfixed is + begin + return (l / to_sfixed (r, l'high, 0)); + end function "/"; + + function "/" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, 0) / r); + end function "/"; + + function "rem" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : NATURAL) + return UNRESOLVED_ufixed is + begin + return (l rem to_ufixed (r, l'high, 0)); + end function "rem"; + + function "rem" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, 0) rem r); + end function "rem"; + + function "rem" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : INTEGER) + return UNRESOLVED_sfixed is + begin + return (l rem to_sfixed (r, l'high, 0)); + end function "rem"; + + function "rem" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, 0) rem r); + end function "rem"; + + function "mod" ( + l : UNRESOLVED_ufixed; -- fixed point input + r : NATURAL) + return UNRESOLVED_ufixed is + begin + return (l mod to_ufixed (r, l'high, 0)); + end function "mod"; + + function "mod" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return (to_ufixed (l, r'high, 0) mod r); + end function "mod"; + + function "mod" ( + l : UNRESOLVED_sfixed; -- fixed point input + r : INTEGER) + return UNRESOLVED_sfixed is + begin + return (l mod to_sfixed (r, l'high, 0)); + end function "mod"; + + function "mod" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return UNRESOLVED_sfixed is + begin + return (to_sfixed (l, r'high, 0) mod r); + end function "mod"; + + -- overloaded ufixed compare functions with integer + function "=" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return BOOLEAN is + begin + return (l = to_ufixed (r, l'high, l'low)); + end function "="; + + function "/=" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return BOOLEAN is + begin + return (l /= to_ufixed (r, l'high, l'low)); + end function "/="; + + function ">=" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return BOOLEAN is + begin + return (l >= to_ufixed (r, l'high, l'low)); + end function ">="; + + function "<=" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return BOOLEAN is + begin + return (l <= to_ufixed (r, l'high, l'low)); + end function "<="; + + function ">" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return BOOLEAN is + begin + return (l > to_ufixed (r, l'high, l'low)); + end function ">"; + + function "<" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return BOOLEAN is + begin + return (l < to_ufixed (r, l'high, l'low)); + end function "<"; + + function "?=" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return STD_ULOGIC is + begin + return (l ?= to_ufixed (r, l'high, l'low)); + end function "?="; + + function "?/=" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return STD_ULOGIC is + begin + return (l ?/= to_ufixed (r, l'high, l'low)); + end function "?/="; + + function "?>=" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return STD_ULOGIC is + begin + return (l ?>= to_ufixed (r, l'high, l'low)); + end function "?>="; + + function "?<=" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return STD_ULOGIC is + begin + return (l ?<= to_ufixed (r, l'high, l'low)); + end function "?<="; + + function "?>" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return STD_ULOGIC is + begin + return (l ?> to_ufixed (r, l'high, l'low)); + end function "?>"; + + function "?<" ( + l : UNRESOLVED_ufixed; + r : NATURAL) -- fixed point input + return STD_ULOGIC is + begin + return (l ?< to_ufixed (r, l'high, l'low)); + end function "?<"; + + function maximum ( + l : UNRESOLVED_ufixed; -- fixed point input + r : NATURAL) + return UNRESOLVED_ufixed is + begin + return maximum (l, to_ufixed (r, l'high, l'low)); + end function maximum; + + function minimum ( + l : UNRESOLVED_ufixed; -- fixed point input + r : NATURAL) + return UNRESOLVED_ufixed is + begin + return minimum (l, to_ufixed (r, l'high, l'low)); + end function minimum; + + -- NATURAL to ufixed + function "=" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) = r); + end function "="; + + function "/=" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) /= r); + end function "/="; + + function ">=" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) >= r); + end function ">="; + + function "<=" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) <= r); + end function "<="; + + function ">" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) > r); + end function ">"; + + function "<" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) < r); + end function "<"; + + function "?=" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?= r); + end function "?="; + + function "?/=" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?/= r); + end function "?/="; + + function "?>=" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?>= r); + end function "?>="; + + function "?<=" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?<= r); + end function "?<="; + + function "?>" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?> r); + end function "?>"; + + function "?<" ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?< r); + end function "?<"; + + function maximum ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return maximum (to_ufixed (l, r'high, r'low), r); + end function maximum; + + function minimum ( + l : NATURAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return minimum (to_ufixed (l, r'high, r'low), r); + end function minimum; + + -- overloaded ufixed compare functions with real + function "=" ( + l : UNRESOLVED_ufixed; + r : REAL) + return BOOLEAN is + begin + return (l = to_ufixed (r, l'high, l'low)); + end function "="; + + function "/=" ( + l : UNRESOLVED_ufixed; + r : REAL) + return BOOLEAN is + begin + return (l /= to_ufixed (r, l'high, l'low)); + end function "/="; + + function ">=" ( + l : UNRESOLVED_ufixed; + r : REAL) + return BOOLEAN is + begin + return (l >= to_ufixed (r, l'high, l'low)); + end function ">="; + + function "<=" ( + l : UNRESOLVED_ufixed; + r : REAL) + return BOOLEAN is + begin + return (l <= to_ufixed (r, l'high, l'low)); + end function "<="; + + function ">" ( + l : UNRESOLVED_ufixed; + r : REAL) + return BOOLEAN is + begin + return (l > to_ufixed (r, l'high, l'low)); + end function ">"; + + function "<" ( + l : UNRESOLVED_ufixed; + r : REAL) + return BOOLEAN is + begin + return (l < to_ufixed (r, l'high, l'low)); + end function "<"; + + function "?=" ( + l : UNRESOLVED_ufixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?= to_ufixed (r, l'high, l'low)); + end function "?="; + + function "?/=" ( + l : UNRESOLVED_ufixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?/= to_ufixed (r, l'high, l'low)); + end function "?/="; + + function "?>=" ( + l : UNRESOLVED_ufixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?>= to_ufixed (r, l'high, l'low)); + end function "?>="; + + function "?<=" ( + l : UNRESOLVED_ufixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?<= to_ufixed (r, l'high, l'low)); + end function "?<="; + + function "?>" ( + l : UNRESOLVED_ufixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?> to_ufixed (r, l'high, l'low)); + end function "?>"; + + function "?<" ( + l : UNRESOLVED_ufixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?< to_ufixed (r, l'high, l'low)); + end function "?<"; + + function maximum ( + l : UNRESOLVED_ufixed; + r : REAL) + return UNRESOLVED_ufixed is + begin + return maximum (l, to_ufixed (r, l'high, l'low)); + end function maximum; + + function minimum ( + l : UNRESOLVED_ufixed; + r : REAL) + return UNRESOLVED_ufixed is + begin + return minimum (l, to_ufixed (r, l'high, l'low)); + end function minimum; + + -- real and ufixed + function "=" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) = r); + end function "="; + + function "/=" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) /= r); + end function "/="; + + function ">=" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) >= r); + end function ">="; + + function "<=" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) <= r); + end function "<="; + + function ">" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) > r); + end function ">"; + + function "<" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return BOOLEAN is + begin + return (to_ufixed (l, r'high, r'low) < r); + end function "<"; + + function "?=" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?= r); + end function "?="; + + function "?/=" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?/= r); + end function "?/="; + + function "?>=" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?>= r); + end function "?>="; + + function "?<=" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?<= r); + end function "?<="; + + function "?>" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?> r); + end function "?>"; + + function "?<" ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_ufixed (l, r'high, r'low) ?< r); + end function "?<"; + + function maximum ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return maximum (to_ufixed (l, r'high, r'low), r); + end function maximum; + + function minimum ( + l : REAL; + r : UNRESOLVED_ufixed) -- fixed point input + return UNRESOLVED_ufixed is + begin + return minimum (to_ufixed (l, r'high, r'low), r); + end function minimum; + + -- overloaded sfixed compare functions with integer + function "=" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return BOOLEAN is + begin + return (l = to_sfixed (r, l'high, l'low)); + end function "="; + + function "/=" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return BOOLEAN is + begin + return (l /= to_sfixed (r, l'high, l'low)); + end function "/="; + + function ">=" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return BOOLEAN is + begin + return (l >= to_sfixed (r, l'high, l'low)); + end function ">="; + + function "<=" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return BOOLEAN is + begin + return (l <= to_sfixed (r, l'high, l'low)); + end function "<="; + + function ">" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return BOOLEAN is + begin + return (l > to_sfixed (r, l'high, l'low)); + end function ">"; + + function "<" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return BOOLEAN is + begin + return (l < to_sfixed (r, l'high, l'low)); + end function "<"; + + function "?=" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return STD_ULOGIC is + begin + return (l ?= to_sfixed (r, l'high, l'low)); + end function "?="; + + function "?/=" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return STD_ULOGIC is + begin + return (l ?/= to_sfixed (r, l'high, l'low)); + end function "?/="; + + function "?>=" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return STD_ULOGIC is + begin + return (l ?>= to_sfixed (r, l'high, l'low)); + end function "?>="; + + function "?<=" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return STD_ULOGIC is + begin + return (l ?<= to_sfixed (r, l'high, l'low)); + end function "?<="; + + function "?>" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return STD_ULOGIC is + begin + return (l ?> to_sfixed (r, l'high, l'low)); + end function "?>"; + + function "?<" ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return STD_ULOGIC is + begin + return (l ?< to_sfixed (r, l'high, l'low)); + end function "?<"; + + function maximum ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return UNRESOLVED_sfixed is + begin + return maximum (l, to_sfixed (r, l'high, l'low)); + end function maximum; + + function minimum ( + l : UNRESOLVED_sfixed; + r : INTEGER) + return UNRESOLVED_sfixed is + begin + return minimum (l, to_sfixed (r, l'high, l'low)); + end function minimum; + + -- integer and sfixed + function "=" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) = r); + end function "="; + + function "/=" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) /= r); + end function "/="; + + function ">=" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) >= r); + end function ">="; + + function "<=" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) <= r); + end function "<="; + + function ">" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) > r); + end function ">"; + + function "<" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) < r); + end function "<"; + + function "?=" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?= r); + end function "?="; + + function "?/=" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?/= r); + end function "?/="; + + function "?>=" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?>= r); + end function "?>="; + + function "?<=" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?<= r); + end function "?<="; + + function "?>" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?> r); + end function "?>"; + + function "?<" ( + l : INTEGER; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?< r); + end function "?<"; + + function maximum ( + l : INTEGER; + r : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return maximum (to_sfixed (l, r'high, r'low), r); + end function maximum; + + function minimum ( + l : INTEGER; + r : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return minimum (to_sfixed (l, r'high, r'low), r); + end function minimum; + + -- overloaded sfixed compare functions with real + function "=" ( + l : UNRESOLVED_sfixed; + r : REAL) + return BOOLEAN is + begin + return (l = to_sfixed (r, l'high, l'low)); + end function "="; + + function "/=" ( + l : UNRESOLVED_sfixed; + r : REAL) + return BOOLEAN is + begin + return (l /= to_sfixed (r, l'high, l'low)); + end function "/="; + + function ">=" ( + l : UNRESOLVED_sfixed; + r : REAL) + return BOOLEAN is + begin + return (l >= to_sfixed (r, l'high, l'low)); + end function ">="; + + function "<=" ( + l : UNRESOLVED_sfixed; + r : REAL) + return BOOLEAN is + begin + return (l <= to_sfixed (r, l'high, l'low)); + end function "<="; + + function ">" ( + l : UNRESOLVED_sfixed; + r : REAL) + return BOOLEAN is + begin + return (l > to_sfixed (r, l'high, l'low)); + end function ">"; + + function "<" ( + l : UNRESOLVED_sfixed; + r : REAL) + return BOOLEAN is + begin + return (l < to_sfixed (r, l'high, l'low)); + end function "<"; + + function "?=" ( + l : UNRESOLVED_sfixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?= to_sfixed (r, l'high, l'low)); + end function "?="; + + function "?/=" ( + l : UNRESOLVED_sfixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?/= to_sfixed (r, l'high, l'low)); + end function "?/="; + + function "?>=" ( + l : UNRESOLVED_sfixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?>= to_sfixed (r, l'high, l'low)); + end function "?>="; + + function "?<=" ( + l : UNRESOLVED_sfixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?<= to_sfixed (r, l'high, l'low)); + end function "?<="; + + function "?>" ( + l : UNRESOLVED_sfixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?> to_sfixed (r, l'high, l'low)); + end function "?>"; + + function "?<" ( + l : UNRESOLVED_sfixed; + r : REAL) + return STD_ULOGIC is + begin + return (l ?< to_sfixed (r, l'high, l'low)); + end function "?<"; + + function maximum ( + l : UNRESOLVED_sfixed; + r : REAL) + return UNRESOLVED_sfixed is + begin + return maximum (l, to_sfixed (r, l'high, l'low)); + end function maximum; + + function minimum ( + l : UNRESOLVED_sfixed; + r : REAL) + return UNRESOLVED_sfixed is + begin + return minimum (l, to_sfixed (r, l'high, l'low)); + end function minimum; + + -- REAL and sfixed + function "=" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) = r); + end function "="; + + function "/=" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) /= r); + end function "/="; + + function ">=" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) >= r); + end function ">="; + + function "<=" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) <= r); + end function "<="; + + function ">" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) > r); + end function ">"; + + function "<" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return BOOLEAN is + begin + return (to_sfixed (l, r'high, r'low) < r); + end function "<"; + + function "?=" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?= r); + end function "?="; + + function "?/=" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?/= r); + end function "?/="; + + function "?>=" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?>= r); + end function "?>="; + + function "?<=" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?<= r); + end function "?<="; + + function "?>" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?> r); + end function "?>"; + + function "?<" ( + l : REAL; + r : UNRESOLVED_sfixed) -- fixed point input + return STD_ULOGIC is + begin + return (to_sfixed (l, r'high, r'low) ?< r); + end function "?<"; + + function maximum ( + l : REAL; + r : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return maximum (to_sfixed (l, r'high, r'low), r); + end function maximum; + + function minimum ( + l : REAL; + r : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return minimum (to_sfixed (l, r'high, r'low), r); + end function minimum; + + -- copied from std_logic_textio + type MVL9plus is ('U', 'X', '0', '1', 'Z', 'W', 'L', 'H', '-', error); + type char_indexed_by_MVL9 is array (STD_ULOGIC) of CHARACTER; + type MVL9_indexed_by_char is array (CHARACTER) of STD_ULOGIC; + type MVL9plus_indexed_by_char is array (CHARACTER) of MVL9plus; + + constant MVL9_to_char : char_indexed_by_MVL9 := "UX01ZWLH-"; + constant char_to_MVL9 : MVL9_indexed_by_char := + ('U' => 'U', 'X' => 'X', '0' => '0', '1' => '1', 'Z' => 'Z', + 'W' => 'W', 'L' => 'L', 'H' => 'H', '-' => '-', others => 'U'); + constant char_to_MVL9plus : MVL9plus_indexed_by_char := + ('U' => 'U', 'X' => 'X', '0' => '0', '1' => '1', 'Z' => 'Z', + 'W' => 'W', 'L' => 'L', 'H' => 'H', '-' => '-', others => error); + constant NBSP : CHARACTER := CHARACTER'val(160); -- space character + constant NUS : STRING(2 to 1) := (others => ' '); + + -- purpose: Skips white space + procedure skip_whitespace ( + L : inout LINE) is + variable readOk : BOOLEAN; + variable c : CHARACTER; + begin + while L /= null and L.all'length /= 0 loop + if (L.all(1) = ' ' or L.all(1) = NBSP or L.all(1) = HT) then + read (l, c, readOk); + else + exit; + end if; + end loop; + end procedure skip_whitespace; + + -- purpose: writes fixed point into a line + procedure write ( + L : inout LINE; -- input line + VALUE : in UNRESOLVED_ufixed; -- fixed point input + JUSTIFIED : in SIDE := right; + FIELD : in WIDTH := 0) is + variable s : STRING(1 to value'length +1) := (others => ' '); + variable sindx : INTEGER; + begin -- function write Example: 0011.1100 + sindx := 1; + for i in value'high downto value'low loop + if i = -1 then + s(sindx) := '.'; + sindx := sindx + 1; + end if; + s(sindx) := MVL9_to_char(STD_ULOGIC(value(i))); + sindx := sindx + 1; + end loop; + write(l, s, justified, field); + end procedure write; + + -- purpose: writes fixed point into a line + procedure write ( + L : inout LINE; -- input line + VALUE : in UNRESOLVED_sfixed; -- fixed point input + JUSTIFIED : in SIDE := right; + FIELD : in WIDTH := 0) is + variable s : STRING(1 to value'length +1); + variable sindx : INTEGER; + begin -- function write Example: 0011.1100 + sindx := 1; + for i in value'high downto value'low loop + if i = -1 then + s(sindx) := '.'; + sindx := sindx + 1; + end if; + s(sindx) := MVL9_to_char(STD_ULOGIC(value(i))); + sindx := sindx + 1; + end loop; + write(l, s, justified, field); + end procedure write; + + procedure READ(L : inout LINE; + VALUE : out UNRESOLVED_ufixed) is + -- Possible data: 00000.0000000 + -- 000000000000 + variable c : CHARACTER; + variable readOk : BOOLEAN; + variable i : INTEGER; -- index variable + variable mv : ufixed (VALUE'range); + variable lastu : BOOLEAN := false; -- last character was an "_" + variable founddot : BOOLEAN := false; -- found a "." + begin -- READ + VALUE := (VALUE'range => 'U'); + Skip_whitespace (L); + if VALUE'length > 0 then -- non Null input string + read (l, c, readOk); + i := value'high; + while i >= VALUE'low loop + if readOk = false then -- Bail out if there was a bad read + report fixed_generic_pkg'instance_name & "READ(ufixed) " + & "End of string encountered" + severity error; + return; + elsif c = '_' then + if i = value'high then + report fixed_generic_pkg'instance_name & "READ(ufixed) " + & "String begins with an ""_""" severity error; + return; + elsif lastu then + report fixed_generic_pkg'instance_name & "READ(ufixed) " + & "Two underscores detected in input string ""__""" + severity error; + return; + else + lastu := true; + end if; + elsif c = '.' then -- binary point + if founddot then + report fixed_generic_pkg'instance_name & "READ(ufixed) " + & "Two binary points found in input string" severity error; + return; + elsif i /= -1 then -- Seperator in the wrong spot + report fixed_generic_pkg'instance_name & "READ(ufixed) " + & "Decimal point does not match number format " + severity error; + return; + end if; + founddot := true; + lastu := false; + elsif c = ' ' or c = NBSP or c = HT then -- reading done. + report fixed_generic_pkg'instance_name & "READ(ufixed) " + & "Short read, Space encounted in input string" + severity error; + return; + elsif char_to_MVL9plus(c) = error then + report fixed_generic_pkg'instance_name & "READ(ufixed) " + & "Character '" & + c & "' read, expected STD_ULOGIC literal." + severity error; + return; + else + mv(i) := char_to_MVL9(c); + i := i - 1; + if i < mv'low then + VALUE := mv; + return; + end if; + lastu := false; + end if; + read(L, c, readOk); + end loop; + end if; + end procedure READ; + + procedure READ(L : inout LINE; + VALUE : out UNRESOLVED_ufixed; + GOOD : out BOOLEAN) is + -- Possible data: 00000.0000000 + -- 000000000000 + variable c : CHARACTER; + variable readOk : BOOLEAN; + variable mv : ufixed (VALUE'range); + variable i : INTEGER; -- index variable + variable lastu : BOOLEAN := false; -- last character was an "_" + variable founddot : BOOLEAN := false; -- found a "." + begin -- READ + VALUE := (VALUE'range => 'U'); + Skip_whitespace (L); + if VALUE'length > 0 then + read (l, c, readOk); + i := value'high; + GOOD := false; + while i >= VALUE'low loop + if not readOk then -- Bail out if there was a bad read + return; + elsif c = '_' then + if i = value'high then -- Begins with an "_" + return; + elsif lastu then -- "__" detected + return; + else + lastu := true; + end if; + elsif c = '.' then -- binary point + if founddot then + return; + elsif i /= -1 then -- Seperator in the wrong spot + return; + end if; + founddot := true; + lastu := false; + elsif (char_to_MVL9plus(c) = error) then -- Illegal character/short read + return; + else + mv(i) := char_to_MVL9(c); + i := i - 1; + if i < mv'low then -- reading done + GOOD := true; + VALUE := mv; + return; + end if; + lastu := false; + end if; + read(L, c, readOk); + end loop; + else + GOOD := true; -- read into a null array + end if; + end procedure READ; + + procedure READ(L : inout LINE; + VALUE : out UNRESOLVED_sfixed) is + variable c : CHARACTER; + variable readOk : BOOLEAN; + variable i : INTEGER; -- index variable + variable mv : sfixed (VALUE'range); + variable lastu : BOOLEAN := false; -- last character was an "_" + variable founddot : BOOLEAN := false; -- found a "." + begin -- READ + VALUE := (VALUE'range => 'U'); + Skip_whitespace (L); + if VALUE'length > 0 then -- non Null input string + read (l, c, readOk); + i := value'high; + while i >= VALUE'low loop + if readOk = false then -- Bail out if there was a bad read + report fixed_generic_pkg'instance_name & "READ(sfixed) " + & "End of string encountered" + severity error; + return; + elsif c = '_' then + if i = value'high then + report fixed_generic_pkg'instance_name & "READ(sfixed) " + & "String begins with an ""_""" severity error; + return; + elsif lastu then + report fixed_generic_pkg'instance_name & "READ(sfixed) " + & "Two underscores detected in input string ""__""" + severity error; + return; + else + lastu := true; + end if; + elsif c = '.' then -- binary point + if founddot then + report fixed_generic_pkg'instance_name & "READ(sfixed) " + & "Two binary points found in input string" severity error; + return; + elsif i /= -1 then -- Seperator in the wrong spot + report fixed_generic_pkg'instance_name & "READ(sfixed) " + & "Decimal point does not match number format " + severity error; + return; + end if; + founddot := true; + lastu := false; + elsif c = ' ' or c = NBSP or c = HT then -- reading done. + report fixed_generic_pkg'instance_name & "READ(sfixed) " + & "Short read, Space encounted in input string" + severity error; + return; + elsif char_to_MVL9plus(c) = error then + report fixed_generic_pkg'instance_name & "READ(sfixed) " + & "Character '" & + c & "' read, expected STD_ULOGIC literal." + severity error; + return; + else + mv(i) := char_to_MVL9(c); + i := i - 1; + if i < mv'low then + VALUE := mv; + return; + end if; + lastu := false; + end if; + read(L, c, readOk); + end loop; + end if; + end procedure READ; + + procedure READ(L : inout LINE; + VALUE : out UNRESOLVED_sfixed; + GOOD : out BOOLEAN) is + variable value_ufixed : UNRESOLVED_ufixed (VALUE'range); + begin -- READ + READ (L => L, VALUE => value_ufixed, GOOD => GOOD); + VALUE := UNRESOLVED_sfixed (value_ufixed); + end procedure READ; + + -- octal read and write + procedure owrite ( + L : inout LINE; -- input line + VALUE : in UNRESOLVED_ufixed; -- fixed point input + JUSTIFIED : in SIDE := right; + FIELD : in WIDTH := 0) is + begin -- Example 03.30 + write (L => L, + VALUE => to_ostring (VALUE), + JUSTIFIED => JUSTIFIED, + FIELD => FIELD); + end procedure owrite; + + procedure owrite ( + L : inout LINE; -- input line + VALUE : in UNRESOLVED_sfixed; -- fixed point input + JUSTIFIED : in SIDE := right; + FIELD : in WIDTH := 0) is + begin -- Example 03.30 + write (L => L, + VALUE => to_ostring (VALUE), + JUSTIFIED => JUSTIFIED, + FIELD => FIELD); + end procedure owrite; + + -- Note that for Octal and Hex read, you can not start with a ".", + -- the read is for numbers formatted "A.BC". These routines go to + -- the nearest bounds, so "F.E" will fit into an sfixed (2 downto -3). + procedure Char2TriBits (C : CHARACTER; + RESULT : out STD_ULOGIC_VECTOR(2 downto 0); + GOOD : out BOOLEAN; + ISSUE_ERROR : in BOOLEAN) is + begin + case c is + when '0' => result := o"0"; good := true; + when '1' => result := o"1"; good := true; + when '2' => result := o"2"; good := true; + when '3' => result := o"3"; good := true; + when '4' => result := o"4"; good := true; + when '5' => result := o"5"; good := true; + when '6' => result := o"6"; good := true; + when '7' => result := o"7"; good := true; + when 'Z' => result := "ZZZ"; good := true; + when 'X' => result := "XXX"; good := true; + when others => + assert not ISSUE_ERROR + report fixed_generic_pkg'instance_name + & "OREAD Error: Read a '" & c & + "', expected an Octal character (0-7)." + severity error; + result := "UUU"; + good := false; + end case; + end procedure Char2TriBits; + + -- purpose: Routines common to the OREAD routines + procedure OREAD_common ( + L : inout LINE; + slv : out STD_ULOGIC_VECTOR; + igood : out BOOLEAN; + idex : out INTEGER; + constant bpoint : in INTEGER; -- binary point + constant message : in BOOLEAN; + constant smath : in BOOLEAN) is + + -- purpose: error message routine + procedure errmes ( + constant mess : in STRING) is -- error message + begin + if message then + if smath then + report fixed_generic_pkg'instance_name + & "OREAD(sfixed) " + & mess + severity error; + else + report fixed_generic_pkg'instance_name + & "OREAD(ufixed) " + & mess + severity error; + end if; + end if; + end procedure errmes; + variable xgood : BOOLEAN; + variable nybble : STD_ULOGIC_VECTOR (2 downto 0); -- 3 bits + variable c : CHARACTER; + variable i : INTEGER; + variable lastu : BOOLEAN := false; -- last character was an "_" + variable founddot : BOOLEAN := false; -- found a dot. + begin + Skip_whitespace (L); + if slv'length > 0 then + i := slv'high; + read (l, c, xgood); + while i > 0 loop + if xgood = false then + errmes ("Error: end of string encountered"); + exit; + elsif c = '_' then + if i = slv'length then + errmes ("Error: String begins with an ""_"""); + xgood := false; + exit; + elsif lastu then + errmes ("Error: Two underscores detected in input string ""__"""); + xgood := false; + exit; + else + lastu := true; + end if; + elsif (c = '.') then + if (i + 1 /= bpoint) then + errmes ("encountered ""."" at wrong index"); + xgood := false; + exit; + elsif i = slv'length then + errmes ("encounted a ""."" at the beginning of the line"); + xgood := false; + exit; + elsif founddot then + errmes ("Two ""."" encounted in input string"); + xgood := false; + exit; + end if; + founddot := true; + lastu := false; + else + Char2triBits(c, nybble, xgood, message); + if not xgood then + exit; + end if; + slv (i downto i-2) := nybble; + i := i - 3; + lastu := false; + end if; + if i > 0 then + read (L, c, xgood); + end if; + end loop; + idex := i; + igood := xgood; + else + igood := true; -- read into a null array + idex := -1; + end if; + end procedure OREAD_common; + + -- Note that for Octal and Hex read, you can not start with a ".", + -- the read is for numbers formatted "A.BC". These routines go to + -- the nearest bounds, so "F.E" will fit into an sfixed (2 downto -3). + procedure OREAD (L : inout LINE; + VALUE : out UNRESOLVED_ufixed) is + constant hbv : INTEGER := (((maximum(3, (VALUE'high+1))+2)/3)*3)-1; + constant lbv : INTEGER := ((mine(0, VALUE'low)-2)/3)*3; + variable slv : STD_ULOGIC_VECTOR (hbv-lbv downto 0); -- high bits + variable valuex : UNRESOLVED_ufixed (hbv downto lbv); + variable igood : BOOLEAN; + variable i : INTEGER; + begin + VALUE := (VALUE'range => 'U'); + OREAD_common ( L => L, + slv => slv, + igood => igood, + idex => i, + bpoint => -lbv, + message => true, + smath => false); + if igood then -- We did not get another error + if not ((i = -1) and -- We read everything, and high bits 0 + (or (slv(hbv-lbv downto VALUE'high+1-lbv)) = '0')) then + report fixed_generic_pkg'instance_name + & "OREAD(ufixed): Vector truncated." + severity error; + else + if (or (slv(VALUE'low-lbv-1 downto 0)) = '1') then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "OREAD(ufixed): Vector truncated" + severity warning; + end if; + valuex := to_ufixed (slv, hbv, lbv); + VALUE := valuex (VALUE'range); + end if; + end if; + end procedure OREAD; + + procedure OREAD(L : inout LINE; + VALUE : out UNRESOLVED_ufixed; + GOOD : out BOOLEAN) is + constant hbv : INTEGER := (((maximum(3, (VALUE'high+1))+2)/3)*3)-1; + constant lbv : INTEGER := ((mine(0, VALUE'low)-2)/3)*3; + variable slv : STD_ULOGIC_VECTOR (hbv-lbv downto 0); -- high bits + variable valuex : UNRESOLVED_ufixed (hbv downto lbv); + variable igood : BOOLEAN; + variable i : INTEGER; + begin + VALUE := (VALUE'range => 'U'); + OREAD_common ( L => L, + slv => slv, + igood => igood, + idex => i, + bpoint => -lbv, + message => false, + smath => false); + if (igood and -- We did not get another error + (i = -1) and -- We read everything, and high bits 0 + (or (slv(hbv-lbv downto VALUE'high+1-lbv)) = '0')) then + valuex := to_ufixed (slv, hbv, lbv); + VALUE := valuex (VALUE'range); + good := true; + else + good := false; + end if; + end procedure OREAD; + + procedure OREAD(L : inout LINE; + VALUE : out UNRESOLVED_sfixed) is + constant hbv : INTEGER := (((maximum(3, (VALUE'high+1))+2)/3)*3)-1; + constant lbv : INTEGER := ((mine(0, VALUE'low)-2)/3)*3; + variable slv : STD_ULOGIC_VECTOR (hbv-lbv downto 0); -- high bits + variable valuex : UNRESOLVED_sfixed (hbv downto lbv); + variable igood : BOOLEAN; + variable i : INTEGER; + begin + VALUE := (VALUE'range => 'U'); + OREAD_common ( L => L, + slv => slv, + igood => igood, + idex => i, + bpoint => -lbv, + message => true, + smath => true); + if igood then -- We did not get another error + if not ((i = -1) and -- We read everything + ((slv(VALUE'high-lbv) = '0' and -- sign bits = extra bits + or (slv(hbv-lbv downto VALUE'high+1-lbv)) = '0') or + (slv(VALUE'high-lbv) = '1' and + and (slv(hbv-lbv downto VALUE'high+1-lbv)) = '1'))) then + report fixed_generic_pkg'instance_name + & "OREAD(sfixed): Vector truncated." + severity error; + else + if (or (slv(VALUE'low-lbv-1 downto 0)) = '1') then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "OREAD(sfixed): Vector truncated" + severity warning; + end if; + valuex := to_sfixed (slv, hbv, lbv); + VALUE := valuex (VALUE'range); + end if; + end if; + end procedure OREAD; + + procedure OREAD(L : inout LINE; + VALUE : out UNRESOLVED_sfixed; + GOOD : out BOOLEAN) is + constant hbv : INTEGER := (((maximum(3, (VALUE'high+1))+2)/3)*3)-1; + constant lbv : INTEGER := ((mine(0, VALUE'low)-2)/3)*3; + variable slv : STD_ULOGIC_VECTOR (hbv-lbv downto 0); -- high bits + variable valuex : UNRESOLVED_sfixed (hbv downto lbv); + variable igood : BOOLEAN; + variable i : INTEGER; + begin + VALUE := (VALUE'range => 'U'); + OREAD_common ( L => L, + slv => slv, + igood => igood, + idex => i, + bpoint => -lbv, + message => false, + smath => true); + if (igood -- We did not get another error + and (i = -1) -- We read everything + and ((slv(VALUE'high-lbv) = '0' and -- sign bits = extra bits + or (slv(hbv-lbv downto VALUE'high+1-lbv)) = '0') or + (slv(VALUE'high-lbv) = '1' and + and (slv(hbv-lbv downto VALUE'high+1-lbv)) = '1'))) then + valuex := to_sfixed (slv, hbv, lbv); + VALUE := valuex (VALUE'range); + good := true; + else + good := false; + end if; + end procedure OREAD; + + -- hex read and write + procedure hwrite ( + L : inout LINE; -- input line + VALUE : in UNRESOLVED_ufixed; -- fixed point input + JUSTIFIED : in SIDE := right; + FIELD : in WIDTH := 0) is + begin -- Example 03.30 + write (L => L, + VALUE => to_hstring (VALUE), + JUSTIFIED => JUSTIFIED, + FIELD => FIELD); + end procedure hwrite; + + -- purpose: writes fixed point into a line + procedure hwrite ( + L : inout LINE; -- input line + VALUE : in UNRESOLVED_sfixed; -- fixed point input + JUSTIFIED : in SIDE := right; + FIELD : in WIDTH := 0) is + begin -- Example 03.30 + write (L => L, + VALUE => to_hstring (VALUE), + JUSTIFIED => JUSTIFIED, + FIELD => FIELD); + end procedure hwrite; + + -- Hex Read and Write procedures for STD_ULOGIC_VECTOR. + -- Modified from the original to be more forgiving. + + procedure Char2QuadBits (C : CHARACTER; + RESULT : out STD_ULOGIC_VECTOR(3 downto 0); + GOOD : out BOOLEAN; + ISSUE_ERROR : in BOOLEAN) is + begin + case c is + when '0' => result := x"0"; good := true; + when '1' => result := x"1"; good := true; + when '2' => result := x"2"; good := true; + when '3' => result := x"3"; good := true; + when '4' => result := x"4"; good := true; + when '5' => result := x"5"; good := true; + when '6' => result := x"6"; good := true; + when '7' => result := x"7"; good := true; + when '8' => result := x"8"; good := true; + when '9' => result := x"9"; good := true; + when 'A' | 'a' => result := x"A"; good := true; + when 'B' | 'b' => result := x"B"; good := true; + when 'C' | 'c' => result := x"C"; good := true; + when 'D' | 'd' => result := x"D"; good := true; + when 'E' | 'e' => result := x"E"; good := true; + when 'F' | 'f' => result := x"F"; good := true; + when 'Z' => result := "ZZZZ"; good := true; + when 'X' => result := "XXXX"; good := true; + when others => + assert not ISSUE_ERROR + report fixed_generic_pkg'instance_name + & "HREAD Error: Read a '" & c & + "', expected a Hex character (0-F)." + severity error; + result := "UUUU"; + good := false; + end case; + end procedure Char2QuadBits; + + -- purpose: Routines common to the HREAD routines + procedure HREAD_common ( + L : inout LINE; + slv : out STD_ULOGIC_VECTOR; + igood : out BOOLEAN; + idex : out INTEGER; + constant bpoint : in INTEGER; -- binary point + constant message : in BOOLEAN; + constant smath : in BOOLEAN) is + + -- purpose: error message routine + procedure errmes ( + constant mess : in STRING) is -- error message + begin + if message then + if smath then + report fixed_generic_pkg'instance_name + & "HREAD(sfixed) " + & mess + severity error; + else + report fixed_generic_pkg'instance_name + & "HREAD(ufixed) " + & mess + severity error; + end if; + end if; + end procedure errmes; + variable xgood : BOOLEAN; + variable nybble : STD_ULOGIC_VECTOR (3 downto 0); -- 4 bits + variable c : CHARACTER; + variable i : INTEGER; + variable lastu : BOOLEAN := false; -- last character was an "_" + variable founddot : BOOLEAN := false; -- found a dot. + begin + Skip_whitespace (L); + if slv'length > 0 then + i := slv'high; + read (l, c, xgood); + while i > 0 loop + if xgood = false then + errmes ("Error: end of string encountered"); + exit; + elsif c = '_' then + if i = slv'length then + errmes ("Error: String begins with an ""_"""); + xgood := false; + exit; + elsif lastu then + errmes ("Error: Two underscores detected in input string ""__"""); + xgood := false; + exit; + else + lastu := true; + end if; + elsif (c = '.') then + if (i + 1 /= bpoint) then + errmes ("encountered ""."" at wrong index"); + xgood := false; + exit; + elsif i = slv'length then + errmes ("encounted a ""."" at the beginning of the line"); + xgood := false; + exit; + elsif founddot then + errmes ("Two ""."" encounted in input string"); + xgood := false; + exit; + end if; + founddot := true; + lastu := false; + else + Char2QuadBits(c, nybble, xgood, message); + if not xgood then + exit; + end if; + slv (i downto i-3) := nybble; + i := i - 4; + lastu := false; + end if; + if i > 0 then + read (L, c, xgood); + end if; + end loop; + idex := i; + igood := xgood; + else + idex := -1; + igood := true; -- read null string + end if; + end procedure HREAD_common; + + procedure HREAD(L : inout LINE; + VALUE : out UNRESOLVED_ufixed) is + constant hbv : INTEGER := (((maximum(4, (VALUE'high+1))+3)/4)*4)-1; + constant lbv : INTEGER := ((mine(0, VALUE'low)-3)/4)*4; + variable slv : STD_ULOGIC_VECTOR (hbv-lbv downto 0); -- high bits + variable valuex : UNRESOLVED_ufixed (hbv downto lbv); + variable igood : BOOLEAN; + variable i : INTEGER; + begin + VALUE := (VALUE'range => 'U'); + HREAD_common ( L => L, + slv => slv, + igood => igood, + idex => i, + bpoint => -lbv, + message => false, + smath => false); + if igood then + if not ((i = -1) and -- We read everything, and high bits 0 + (or (slv(hbv-lbv downto VALUE'high+1-lbv)) = '0')) then + report fixed_generic_pkg'instance_name + & "HREAD(ufixed): Vector truncated." + severity error; + else + if (or (slv(VALUE'low-lbv-1 downto 0)) = '1') then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "HREAD(ufixed): Vector truncated" + severity warning; + end if; + valuex := to_ufixed (slv, hbv, lbv); + VALUE := valuex (VALUE'range); + end if; + end if; + end procedure HREAD; + + procedure HREAD(L : inout LINE; + VALUE : out UNRESOLVED_ufixed; + GOOD : out BOOLEAN) is + constant hbv : INTEGER := (((maximum(4, (VALUE'high+1))+3)/4)*4)-1; + constant lbv : INTEGER := ((mine(0, VALUE'low)-3)/4)*4; + variable slv : STD_ULOGIC_VECTOR (hbv-lbv downto 0); -- high bits + variable valuex : UNRESOLVED_ufixed (hbv downto lbv); + variable igood : BOOLEAN; + variable i : INTEGER; + begin + VALUE := (VALUE'range => 'U'); + HREAD_common ( L => L, + slv => slv, + igood => igood, + idex => i, + bpoint => -lbv, + message => false, + smath => false); + if (igood and -- We did not get another error + (i = -1) and -- We read everything, and high bits 0 + (or (slv(hbv-lbv downto VALUE'high+1-lbv)) = '0')) then + valuex := to_ufixed (slv, hbv, lbv); + VALUE := valuex (VALUE'range); + good := true; + else + good := false; + end if; + end procedure HREAD; + + procedure HREAD(L : inout LINE; + VALUE : out UNRESOLVED_sfixed) is + constant hbv : INTEGER := (((maximum(4, (VALUE'high+1))+3)/4)*4)-1; + constant lbv : INTEGER := ((mine(0, VALUE'low)-3)/4)*4; + variable slv : STD_ULOGIC_VECTOR (hbv-lbv downto 0); -- high bits + variable valuex : UNRESOLVED_sfixed (hbv downto lbv); + variable igood : BOOLEAN; + variable i : INTEGER; + begin + VALUE := (VALUE'range => 'U'); + HREAD_common ( L => L, + slv => slv, + igood => igood, + idex => i, + bpoint => -lbv, + message => true, + smath => true); + if igood then -- We did not get another error + if not ((i = -1) -- We read everything + and ((slv(VALUE'high-lbv) = '0' and -- sign bits = extra bits + or (slv(hbv-lbv downto VALUE'high+1-lbv)) = '0') or + (slv(VALUE'high-lbv) = '1' and + and (slv(hbv-lbv downto VALUE'high+1-lbv)) = '1'))) then + report fixed_generic_pkg'instance_name + & "HREAD(sfixed): Vector truncated." + severity error; + else + if (or (slv(VALUE'low-lbv-1 downto 0)) = '1') then + assert NO_WARNING + report fixed_generic_pkg'instance_name + & "HREAD(sfixed): Vector truncated" + severity warning; + end if; + valuex := to_sfixed (slv, hbv, lbv); + VALUE := valuex (VALUE'range); + end if; + end if; + end procedure HREAD; + + procedure HREAD(L : inout LINE; + VALUE : out UNRESOLVED_sfixed; + GOOD : out BOOLEAN) is + constant hbv : INTEGER := (((maximum(4, (VALUE'high+1))+3)/4)*4)-1; + constant lbv : INTEGER := ((mine(0, VALUE'low)-3)/4)*4; + variable slv : STD_ULOGIC_VECTOR (hbv-lbv downto 0); -- high bits + variable valuex : UNRESOLVED_sfixed (hbv downto lbv); + variable igood : BOOLEAN; + variable i : INTEGER; + begin + VALUE := (VALUE'range => 'U'); + HREAD_common ( L => L, + slv => slv, + igood => igood, + idex => i, + bpoint => -lbv, + message => false, + smath => true); + if (igood and -- We did not get another error + (i = -1) and -- We read everything + ((slv(VALUE'high-lbv) = '0' and -- sign bits = extra bits + or (slv(hbv-lbv downto VALUE'high+1-lbv)) = '0') or + (slv(VALUE'high-lbv) = '1' and + and (slv(hbv-lbv downto VALUE'high+1-lbv)) = '1'))) then + valuex := to_sfixed (slv, hbv, lbv); + VALUE := valuex (VALUE'range); + good := true; + else + good := false; + end if; + end procedure HREAD; + + -- To_string functions. Useful in "report" statements. + -- Example: report "result was " & to_string(result); + function to_string (value : UNRESOLVED_ufixed) return STRING is + variable s : STRING(1 to value'length +1) := (others => ' '); + variable subval : UNRESOLVED_ufixed (value'high downto -1); + variable sindx : INTEGER; + begin + if value'length < 1 then + return NUS; + else + if value'high < 0 then + if value(value'high) = 'Z' then + return to_string (resize (sfixed(value), 0, value'low)); + else + return to_string (resize (value, 0, value'low)); + end if; + elsif value'low >= 0 then + if Is_X (value(value'low)) then + subval := (others => value(value'low)); + subval (value'range) := value; + return to_string(subval); + else + return to_string (resize (value, value'high, -1)); + end if; + else + sindx := 1; + for i in value'high downto value'low loop + if i = -1 then + s(sindx) := '.'; + sindx := sindx + 1; + end if; + s(sindx) := MVL9_to_char(STD_ULOGIC(value(i))); + sindx := sindx + 1; + end loop; + return s; + end if; + end if; + end function to_string; + + function to_string (value : UNRESOLVED_sfixed) return STRING is + variable s : STRING(1 to value'length + 1) := (others => ' '); + variable subval : UNRESOLVED_sfixed (value'high downto -1); + variable sindx : INTEGER; + begin + if value'length < 1 then + return NUS; + else + if value'high < 0 then + return to_string (resize (value, 0, value'low)); + elsif value'low >= 0 then + if Is_X (value(value'low)) then + subval := (others => value(value'low)); + subval (value'range) := value; + return to_string(subval); + else + return to_string (resize (value, value'high, -1)); + end if; + else + sindx := 1; + for i in value'high downto value'low loop + if i = -1 then + s(sindx) := '.'; + sindx := sindx + 1; + end if; + s(sindx) := MVL9_to_char(STD_ULOGIC(value(i))); + sindx := sindx + 1; + end loop; + return s; + end if; + end if; + end function to_string; + + function to_ostring (value : UNRESOLVED_ufixed) return STRING is + constant lne : INTEGER := (-VALUE'low+2)/3; + variable subval : UNRESOLVED_ufixed (value'high downto -3); + variable lpad : STD_ULOGIC_VECTOR (0 to (lne*3 + VALUE'low) -1); + variable slv : STD_ULOGIC_VECTOR (value'length-1 downto 0); + begin + if value'length < 1 then + return NUS; + else + if value'high < 0 then + if value(value'high) = 'Z' then + return to_ostring (resize (sfixed(value), 2, value'low)); + else + return to_ostring (resize (value, 2, value'low)); + end if; + elsif value'low >= 0 then + if Is_X (value(value'low)) then + subval := (others => value(value'low)); + subval (value'range) := value; + return to_ostring(subval); + else + return to_ostring (resize (value, value'high, -3)); + end if; + else + slv := to_sulv (value); + if Is_X (value (value'low)) then + lpad := (others => value (value'low)); + else + lpad := (others => '0'); + end if; + return to_ostring(slv(slv'high downto slv'high-VALUE'high)) + & "." + & to_ostring(slv(slv'high-VALUE'high-1 downto 0) & lpad); + end if; + end if; + end function to_ostring; + + function to_hstring (value : UNRESOLVED_ufixed) return STRING is + constant lne : INTEGER := (-VALUE'low+3)/4; + variable subval : UNRESOLVED_ufixed (value'high downto -4); + variable lpad : STD_ULOGIC_VECTOR (0 to (lne*4 + VALUE'low) -1); + variable slv : STD_ULOGIC_VECTOR (value'length-1 downto 0); + begin + if value'length < 1 then + return NUS; + else + if value'high < 0 then + if value(value'high) = 'Z' then + return to_hstring (resize (sfixed(value), 3, value'low)); + else + return to_hstring (resize (value, 3, value'low)); + end if; + elsif value'low >= 0 then + if Is_X (value(value'low)) then + subval := (others => value(value'low)); + subval (value'range) := value; + return to_hstring(subval); + else + return to_hstring (resize (value, value'high, -4)); + end if; + else + slv := to_sulv (value); + if Is_X (value (value'low)) then + lpad := (others => value(value'low)); + else + lpad := (others => '0'); + end if; + return to_hstring(slv(slv'high downto slv'high-VALUE'high)) + & "." + & to_hstring(slv(slv'high-VALUE'high-1 downto 0)&lpad); + end if; + end if; + end function to_hstring; + + function to_ostring (value : UNRESOLVED_sfixed) return STRING is + constant ne : INTEGER := ((value'high+1)+2)/3; + variable pad : STD_ULOGIC_VECTOR(0 to (ne*3 - (value'high+1)) - 1); + constant lne : INTEGER := (-VALUE'low+2)/3; + variable subval : UNRESOLVED_sfixed (value'high downto -3); + variable lpad : STD_ULOGIC_VECTOR (0 to (lne*3 + VALUE'low) -1); + variable slv : STD_ULOGIC_VECTOR (VALUE'high - VALUE'low downto 0); + begin + if value'length < 1 then + return NUS; + else + if value'high < 0 then + return to_ostring (resize (value, 2, value'low)); + elsif value'low >= 0 then + if Is_X (value(value'low)) then + subval := (others => value(value'low)); + subval (value'range) := value; + return to_ostring(subval); + else + return to_ostring (resize (value, value'high, -3)); + end if; + else + pad := (others => value(value'high)); + slv := to_sulv (value); + if Is_X (value (value'low)) then + lpad := (others => value(value'low)); + else + lpad := (others => '0'); + end if; + return to_ostring(pad & slv(slv'high downto slv'high-VALUE'high)) + & "." + & to_ostring(slv(slv'high-VALUE'high-1 downto 0) & lpad); + end if; + end if; + end function to_ostring; + + function to_hstring (value : UNRESOLVED_sfixed) return STRING is + constant ne : INTEGER := ((value'high+1)+3)/4; + variable pad : STD_ULOGIC_VECTOR(0 to (ne*4 - (value'high+1)) - 1); + constant lne : INTEGER := (-VALUE'low+3)/4; + variable subval : UNRESOLVED_sfixed (value'high downto -4); + variable lpad : STD_ULOGIC_VECTOR (0 to (lne*4 + VALUE'low) -1); + variable slv : STD_ULOGIC_VECTOR (value'length-1 downto 0); + begin + if value'length < 1 then + return NUS; + else + if value'high < 0 then + return to_hstring (resize (value, 3, value'low)); + elsif value'low >= 0 then + if Is_X (value(value'low)) then + subval := (others => value(value'low)); + subval (value'range) := value; + return to_hstring(subval); + else + return to_hstring (resize (value, value'high, -4)); + end if; + else + slv := to_sulv (value); + pad := (others => value(value'high)); + if Is_X (value (value'low)) then + lpad := (others => value(value'low)); + else + lpad := (others => '0'); + end if; + return to_hstring(pad & slv(slv'high downto slv'high-VALUE'high)) + & "." + & to_hstring(slv(slv'high-VALUE'high-1 downto 0) & lpad); + end if; + end if; + end function to_hstring; + + -- From string functions allow you to convert a string into a fixed + -- point number. Example: + -- signal uf1 : ufixed (3 downto -3); + -- uf1 <= from_string ("0110.100", uf1'high, uf1'low); -- 6.5 + -- The "." is optional in this syntax, however it exist and is + -- in the wrong location an error is produced. Overflow will + -- result in saturation. + function from_string ( + bstring : STRING; -- binary string + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (left_index downto right_index); + variable L : LINE; + variable good : BOOLEAN; + begin + L := new STRING'(bstring); + read (L, result, good); + deallocate (L); + assert (good) + report fixed_generic_pkg'instance_name + & "from_string: Bad string "& bstring severity error; + return result; + end function from_string; + + -- Octal and hex conversions work as follows: + -- uf1 <= from_hstring ("6.8", 3, -3); -- 6.5 (bottom zeros dropped) + -- uf1 <= from_ostring ("06.4", 3, -3); -- 6.5 (top zeros dropped) + function from_ostring ( + ostring : STRING; -- Octal string + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (left_index downto right_index); + variable L : LINE; + variable good : BOOLEAN; + begin + L := new STRING'(ostring); + oread (L, result, good); + deallocate (L); + assert (good) + report fixed_generic_pkg'instance_name + & "from_ostring: Bad string "& ostring severity error; + return result; + end function from_ostring; + + function from_hstring ( + hstring : STRING; -- hex string + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_ufixed + is + variable result : UNRESOLVED_ufixed (left_index downto right_index); + variable L : LINE; + variable good : BOOLEAN; + begin + L := new STRING'(hstring); + hread (L, result, good); + deallocate (L); + assert (good) + report fixed_generic_pkg'instance_name + & "from_hstring: Bad string "& hstring severity error; + return result; + end function from_hstring; + + function from_string ( + bstring : STRING; -- binary string + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (left_index downto right_index); + variable L : LINE; + variable good : BOOLEAN; + begin + L := new STRING'(bstring); + read (L, result, good); + deallocate (L); + assert (good) + report fixed_generic_pkg'instance_name + & "from_string: Bad string "& bstring severity error; + return result; + end function from_string; + + function from_ostring ( + ostring : STRING; -- Octal string + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (left_index downto right_index); + variable L : LINE; + variable good : BOOLEAN; + begin + L := new STRING'(ostring); + oread (L, result, good); + deallocate (L); + assert (good) + report fixed_generic_pkg'instance_name + & "from_ostring: Bad string "& ostring severity error; + return result; + end function from_ostring; + + function from_hstring ( + hstring : STRING; -- hex string + constant left_index : INTEGER; + constant right_index : INTEGER) + return UNRESOLVED_sfixed + is + variable result : UNRESOLVED_sfixed (left_index downto right_index); + variable L : LINE; + variable good : BOOLEAN; + begin + L := new STRING'(hstring); + hread (L, result, good); + deallocate (L); + assert (good) + report fixed_generic_pkg'instance_name + & "from_hstring: Bad string "& hstring severity error; + return result; + end function from_hstring; + + -- Same as above, "size_res" is used for it's range only. + function from_string ( + bstring : STRING; -- binary string + size_res : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed is + begin + return from_string (bstring, size_res'high, size_res'low); + end function from_string; + + function from_ostring ( + ostring : STRING; -- Octal string + size_res : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed is + begin + return from_ostring (ostring, size_res'high, size_res'low); + end function from_ostring; + + function from_hstring ( + hstring : STRING; -- hex string + size_res : UNRESOLVED_ufixed) + return UNRESOLVED_ufixed is + begin + return from_hstring(hstring, size_res'high, size_res'low); + end function from_hstring; + + function from_string ( + bstring : STRING; -- binary string + size_res : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return from_string (bstring, size_res'high, size_res'low); + end function from_string; + + function from_ostring ( + ostring : STRING; -- Octal string + size_res : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return from_ostring (ostring, size_res'high, size_res'low); + end function from_ostring; + + function from_hstring ( + hstring : STRING; -- hex string + size_res : UNRESOLVED_sfixed) + return UNRESOLVED_sfixed is + begin + return from_hstring (hstring, size_res'high, size_res'low); + end function from_hstring; + + -- Direct conversion functions. Example: + -- signal uf1 : ufixed (3 downto -3); + -- uf1 <= from_string ("0110.100"); -- 6.5 + -- In this case the "." is not optional, and the size of + -- the output must match exactly. + -- purpose: Calculate the string boundaries + procedure calculate_string_boundry ( + arg : in STRING; -- input string + left_index : out INTEGER; -- left + right_index : out INTEGER) is -- right + -- examples "10001.111" would return +4, -3 + -- "07X.44" would return +2, -2 (then the octal routine would multiply) + -- "A_B_._C" would return +1, -1 (then the hex routine would multiply) + alias xarg : STRING (arg'length downto 1) is arg; -- make it downto range + variable l, r : INTEGER; -- internal indexes + variable founddot : BOOLEAN := false; + begin + if arg'length > 0 then + l := xarg'high - 1; + r := 0; + for i in xarg'range loop + if xarg(i) = '_' then + if r = 0 then + l := l - 1; + else + r := r + 1; + end if; + elsif xarg(i) = ' ' or xarg(i) = NBSP or xarg(i) = HT then + report fixed_generic_pkg'instance_name + & "Found a space in the input STRING " & xarg + severity error; + elsif xarg(i) = '.' then + if founddot then + report fixed_generic_pkg'instance_name + & "Found two binary points in input string " & xarg + severity error; + else + l := l - i; + r := -i + 1; + founddot := true; + end if; + end if; + end loop; + left_index := l; + right_index := r; + else + left_index := 0; + right_index := 0; + end if; + end procedure calculate_string_boundry; + + -- Direct conversion functions. Example: + -- signal uf1 : ufixed (3 downto -3); + -- uf1 <= from_string ("0110.100"); -- 6.5 + -- In this case the "." is not optional, and the size of + -- the output must match exactly. + function from_string ( + bstring : STRING) -- binary string + return UNRESOLVED_ufixed + is + variable left_index, right_index : INTEGER; + begin + calculate_string_boundry (bstring, left_index, right_index); + return from_string (bstring, left_index, right_index); + end function from_string; + + -- Direct octal and hex conversion functions. In this case + -- the string lengths must match. Example: + -- signal sf1 := sfixed (5 downto -3); + -- sf1 <= from_ostring ("71.4") -- -6.5 + function from_ostring ( + ostring : STRING) -- Octal string + return UNRESOLVED_ufixed + is + variable left_index, right_index : INTEGER; + begin + calculate_string_boundry (ostring, left_index, right_index); + return from_ostring (ostring, ((left_index+1)*3)-1, right_index*3); + end function from_ostring; + + function from_hstring ( + hstring : STRING) -- hex string + return UNRESOLVED_ufixed + is + variable left_index, right_index : INTEGER; + begin + calculate_string_boundry (hstring, left_index, right_index); + return from_hstring (hstring, ((left_index+1)*4)-1, right_index*4); + end function from_hstring; + + function from_string ( + bstring : STRING) -- binary string + return UNRESOLVED_sfixed + is + variable left_index, right_index : INTEGER; + begin + calculate_string_boundry (bstring, left_index, right_index); + return from_string (bstring, left_index, right_index); + end function from_string; + + function from_ostring ( + ostring : STRING) -- Octal string + return UNRESOLVED_sfixed + is + variable left_index, right_index : INTEGER; + begin + calculate_string_boundry (ostring, left_index, right_index); + return from_ostring (ostring, ((left_index+1)*3)-1, right_index*3); + end function from_ostring; + + function from_hstring ( + hstring : STRING) -- hex string + return UNRESOLVED_sfixed + is + variable left_index, right_index : INTEGER; + begin + calculate_string_boundry (hstring, left_index, right_index); + return from_hstring (hstring, ((left_index+1)*4)-1, right_index*4); + end function from_hstring; + +end package body fixed_generic_pkg; |