| 1 |
4 |
aloy.amber |
library ieee;
|
| 2 |
|
|
use ieee.std_logic_1164.all;
|
| 3 |
|
|
use ieee.numeric_std.all;
|
| 4 |
|
|
|
| 5 |
|
|
package fp_generic is
|
| 6 |
|
|
|
| 7 |
|
|
subtype fp_type is std_logic_vector(31 downto 0);
|
| 8 |
|
|
subtype fp_sign_type is std_logic;
|
| 9 |
|
|
subtype fp_exp_type is unsigned(7 downto 0);
|
| 10 |
|
|
subtype fp_mantissa_type is unsigned(23 downto 0);
|
| 11 |
|
|
subtype fp_long_mantissa_type is unsigned(47 downto 0);
|
| 12 |
|
|
|
| 13 |
|
|
subtype fp_error_type is std_logic_vector(5 downto 0);
|
| 14 |
|
|
constant FP_ERR_INVALID:fp_error_type:="000001";
|
| 15 |
|
|
constant FP_ERR_DIVBYZERO:fp_error_type:="000100";
|
| 16 |
|
|
constant FP_ERR_OVERFLOW:fp_error_type:="001000";
|
| 17 |
|
|
constant FP_ERR_UNDERFLOW:fp_error_type:="010000";
|
| 18 |
|
|
constant FP_ERR_INEXACT:fp_error_type:="100000";
|
| 19 |
|
|
|
| 20 |
|
|
function fp_sign(fp:fp_type) return fp_sign_type;
|
| 21 |
|
|
function fp_exp(fp:fp_type) return fp_exp_type;
|
| 22 |
|
|
function fp_mantissa(fp:fp_type) return fp_mantissa_type;
|
| 23 |
|
|
|
| 24 |
|
|
function fp_is_normal(fp:fp_type) return boolean;
|
| 25 |
|
|
function fp_is_zero(fp:fp_type) return boolean;
|
| 26 |
|
|
function fp_is_subnormal(fp:fp_type) return boolean;
|
| 27 |
|
|
function fp_is_infinite(fp:fp_type) return boolean;
|
| 28 |
|
|
function fp_is_nan(fp:fp_type) return boolean;
|
| 29 |
|
|
function fp_is_signalling(fp:fp_type) return boolean;
|
| 30 |
|
|
function fp_is_quiet(fp:fp_type) return boolean;
|
| 31 |
|
|
|
| 32 |
|
|
end package;
|
| 33 |
|
|
|
| 34 |
|
|
package body fp_generic is
|
| 35 |
|
|
|
| 36 |
|
|
function fp_sign(fp:fp_type) return fp_sign_type is
|
| 37 |
|
|
begin
|
| 38 |
|
|
return fp(31);
|
| 39 |
|
|
end function fp_sign;
|
| 40 |
|
|
|
| 41 |
|
|
function fp_exp(fp:fp_type) return fp_exp_type is
|
| 42 |
|
|
begin
|
| 43 |
|
|
return unsigned(fp(30 downto 23));
|
| 44 |
|
|
end function fp_exp;
|
| 45 |
|
|
|
| 46 |
|
|
function fp_mantissa(fp:fp_type) return fp_mantissa_type is
|
| 47 |
|
|
begin
|
| 48 |
|
|
return unsigned("1"&fp(22 downto 0)); -- Prepend implied '1' bit of IEEE-754 mantissa in order to return a 24 bit entity
|
| 49 |
|
|
end function fp_mantissa;
|
| 50 |
|
|
|
| 51 |
|
|
function fp_is_normal(fp:fp_type) return boolean is
|
| 52 |
|
|
variable e:fp_exp_type;
|
| 53 |
|
|
begin
|
| 54 |
|
|
e:=fp_exp(fp);
|
| 55 |
|
|
|
| 56 |
|
|
return (e/=(others=>'0')) and (e/=(others=>'1'));
|
| 57 |
|
|
end function fp_is_normal;
|
| 58 |
|
|
|
| 59 |
|
|
function fp_is_zero(fp:fp_type) return boolean is
|
| 60 |
|
|
begin
|
| 61 |
|
|
return (unsigned(fp_exp(fp))=0) and (unsigned(fp_mantissa(fp))=0);
|
| 62 |
|
|
end function fp_is_zero;
|
| 63 |
|
|
|
| 64 |
|
|
function fp_is_subnormal(fp:fp_type) return boolean is
|
| 65 |
|
|
begin
|
| 66 |
|
|
return (fp_exp(fp)=(others=>'0')) and (fp_mantissa(fp)/=(others=>'0'));
|
| 67 |
|
|
end function fp_is_subnormal;
|
| 68 |
|
|
|
| 69 |
|
|
function fp_is_infinite(fp:fp_type) return boolean is
|
| 70 |
|
|
begin
|
| 71 |
|
|
return (fp_exp(fp)=(others=>'1')) and (fp_mantissa(fp)=(others=>'0'));
|
| 72 |
|
|
end function fp_is_infinite;
|
| 73 |
|
|
|
| 74 |
|
|
function fp_is_nan(fp:fp_type) return boolean is
|
| 75 |
|
|
begin
|
| 76 |
|
|
return (fp_exp(fp)=(others=>'1')) and (fp_mantissa(fp)/=(others=>'0'));
|
| 77 |
|
|
end function fp_is_nan;
|
| 78 |
|
|
|
| 79 |
|
|
function fp_is_signalling(fp:fp_type) return boolean is
|
| 80 |
|
|
begin
|
| 81 |
|
|
return fp_is_nan(fp) and fp_mantissa(fp)(22)='0';
|
| 82 |
|
|
end function fp_is_signalling;
|
| 83 |
|
|
|
| 84 |
|
|
function fp_is_quiet(fp:fp_type) return boolean is
|
| 85 |
|
|
begin
|
| 86 |
|
|
return fp_is_nan(fp) and fp_mantissa(fp)(22)='1';
|
| 87 |
|
|
end function fp_is_quiet;
|
| 88 |
|
|
|
| 89 |
|
|
end package body fp_generic;
|
