jens/vhdl
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
Files
master
vhdl/lib/Standard/ieee/numeric_bit.vhdl
T
jens e17a1eefb5 - initial version 
git-svn-id: http://moon:8086/svn/vhdl/trunk@1073 cc03376c-175c-47c8-b038-4cd826a8556b
2015-02-07 06:35:28 +00:00

814 lines
32 KiB
VHDL
Raw Permalink Blame History

-- ----------------------------------------------------------------------------
--
-- Copyright 1995 by IEEE. All rights reserved.
--
--This source file is considered by the IEEE to be an essential part of the use
-- of the standard 1076.3 and as such may be distributed without change, except
--as permitted by the standard. This source file may not be sold or distributed
-- for profit. This package may be modified to include additional data required
-- by tools, but must in no way change the external interfaces or simulation
-- behaviour 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 approved package declaration. The package body may be
-- changed only in accordance with the terms of clauses 7.1 and 7.2 of the
-- standard.
--
-- Title : Standard VHDL Synthesis Package (1076.3, NUMERIC_BIT)
--
-- Library : This package shall be compiled into a library symbolically
-- : named IEEE.
--
-- Developers : IEEE DASC Synthesis Working Group, PAR 1076.3
--
-- Purpose : This package defines numeric types and arithmetic functions
-- : for use with synthesis tools. Two numeric types are defined:
-- : -- > UNSIGNED: represents an UNSIGNED number in vector form
-- : -- > SIGNED: represents a SIGNED number in vector form
-- : The base element type is type BIT.
-- : The leftmost bit is treated as the most significant bit.
-- : Signed vectors are represented in two's complement form.
-- : This package contains overloaded arithmetic operators on
-- : the SIGNED and UNSIGNED types. The package also contains
-- : useful type conversions functions, clock detection
-- : functions, and other utility functions.
-- :
-- : If any argument to a function is a null array, a null array is
-- : returned (exceptions, if any, are noted individually).
--
-- Limitation :
--
-- Note : No declarations or definitions shall be included in,
-- : or excluded from this package. The "package declaration"
-- : defines the types, subtypes and declarations of
-- : NUMERIC_BIT. The NUMERIC_BIT package body shall be
-- : considered the formal definition of the semantics of
-- : this package. Tool developers may choose to implement
-- : the package body in the most efficient manner available
-- : to them.
-- :
-- -----------------------------------------------------------------------------
-- Version : 2.4
-- Date : 12 April 1995
-- ----------------------------------------------------------------------------
package NUMERIC_BIT is
constant CopyRightNotice: STRING
:= "Copyright 1995 IEEE. All rights reserved.";
--===========================================================================
-- Numeric array type definitions
--===========================================================================
type UNSIGNED is array (NATURAL range <> ) of BIT;
type SIGNED is array (NATURAL range <> ) of BIT;
--===========================================================================
-- Arithmetic Operators:
--===========================================================================
-- Id: A.1
function "abs" (ARG: SIGNED) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0).
-- Result: Returns the absolute value of a SIGNED vector ARG.
-- Id: A.2
function "-" (ARG: SIGNED) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0).
-- Result: Returns the value of the unary minus operation on a
-- SIGNED vector ARG.
--===========================================================================
-- Id: A.3
function "+" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(MAX(L'LENGTH, R'LENGTH)-1 downto 0).
-- Result: Adds two UNSIGNED vectors that may be of different lengths.
-- Id: A.4
function "+" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(MAX(L'LENGTH, R'LENGTH)-1 downto 0).
-- Result: Adds two SIGNED vectors that may be of different lengths.
-- Id: A.5
function "+" (L: UNSIGNED; R: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0).
-- Result: Adds an UNSIGNED vector, L, with a non-negative INTEGER, R.
-- Id: A.6
function "+" (L: NATURAL; R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(R'LENGTH-1 downto 0).
-- Result: Adds a non-negative INTEGER, L, with an UNSIGNED vector, R.
-- Id: A.7
function "+" (L: INTEGER; R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(R'LENGTH-1 downto 0).
-- Result: Adds an INTEGER, L(may be positive or negative), to a SIGNED
-- vector, R.
-- Id: A.8
function "+" (L: SIGNED; R: INTEGER) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0).
-- Result: Adds a SIGNED vector, L, to an INTEGER, R.
--===========================================================================
-- Id: A.9
function "-" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(MAX(L'LENGTH, R'LENGTH)-1 downto 0).
-- Result: Subtracts two UNSIGNED vectors that may be of different lengths.
-- Id: A.10
function "-" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(MAX(L'LENGTH, R'LENGTH)-1 downto 0).
-- Result: Subtracts a SIGNED vector, R, from another SIGNED vector, L,
-- that may possibly be of different lengths.
-- Id: A.11
function "-" (L: UNSIGNED; R: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0).
-- Result: Subtracts a non-negative INTEGER, R, from an UNSIGNED vector, L.
-- Id: A.12
function "-" (L: NATURAL; R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(R'LENGTH-1 downto 0).
-- Result: Subtracts an UNSIGNED vector, R, from a non-negative INTEGER, L.
-- Id: A.13
function "-" (L: SIGNED; R: INTEGER) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0).
-- Result: Subtracts an INTEGER, R, from a SIGNED vector, L.
-- Id: A.14
function "-" (L: INTEGER; R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(R'LENGTH-1 downto 0).
-- Result: Subtracts a SIGNED vector, R, from an INTEGER, L.
--===========================================================================
-- Id: A.15
function "*" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED((L'LENGTH+R'LENGTH-1) downto 0).
-- Result: Performs the multiplication operation on two UNSIGNED vectors
-- that may possibly be of different lengths.
-- Id: A.16
function "*" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED((L'LENGTH+R'LENGTH-1) downto 0)
-- Result: Multiplies two SIGNED vectors that may possibly be of
-- different lengths.
-- Id: A.17
function "*" (L: UNSIGNED; R: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED((L'LENGTH+L'LENGTH-1) downto 0).
-- Result: Multiplies an UNSIGNED vector, L, with a non-negative
-- INTEGER, R. R is converted to an UNSIGNED vector of
-- size L'LENGTH before multiplication.
-- Id: A.18
function "*" (L: NATURAL; R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED((R'LENGTH+R'LENGTH-1) downto 0).
-- Result: Multiplies an UNSIGNED vector, R, with a non-negative
-- INTEGER, L. L is converted to an UNSIGNED vector of
-- size R'LENGTH before multiplication.
-- Id: A.19
function "*" (L: SIGNED; R: INTEGER) return SIGNED;
-- Result subtype: SIGNED((L'LENGTH+L'LENGTH-1) downto 0)
-- Result: Multiplies a SIGNED vector, L, with an INTEGER, R. R is
-- converted to a SIGNED vector of size L'LENGTH before
-- multiplication.
-- Id: A.20
function "*" (L: INTEGER; R: SIGNED) return SIGNED;
-- Result subtype: SIGNED((R'LENGTH+R'LENGTH-1) downto 0)
-- Result: Multiplies a SIGNED vector, R, with an INTEGER, L. L is
-- converted to a SIGNED vector of size R'LENGTH before
-- multiplication.
--===========================================================================
--
-- NOTE: If second argument is zero for "/" operator, a severity level
-- of ERROR is issued.
-- Id: A.21
function "/" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Divides an UNSIGNED vector, L, by another UNSIGNED vector, R.
-- Id: A.22
function "/" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Divides an SIGNED vector, L, by another SIGNED vector, R.
-- Id: A.23
function "/" (L: UNSIGNED; R: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Divides an UNSIGNED vector, L, by a non-negative INTEGER, R.
-- If NO_OF_BITS(R) > L'LENGTH, result is truncated to L'LENGTH.
-- Id: A.24
function "/" (L: NATURAL; R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(R'LENGTH-1 downto 0)
-- Result: Divides a non-negative INTEGER, L, by an UNSIGNED vector, R.
-- If NO_OF_BITS(L) > R'LENGTH, result is truncated to R'LENGTH.
-- Id: A.25
function "/" (L: SIGNED; R: INTEGER) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Divides a SIGNED vector, L, by an INTEGER, R.
-- If NO_OF_BITS(R) > L'LENGTH, result is truncated to L'LENGTH.
-- Id: A.26
function "/" (L: INTEGER; R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(R'LENGTH-1 downto 0)
-- Result: Divides an INTEGER, L, by a SIGNED vector, R.
-- If NO_OF_BITS(L) > R'LENGTH, result is truncated to R'LENGTH.
--===========================================================================
--
-- NOTE: If second argument is zero for "rem" operator, a severity level
-- of ERROR is issued.
-- Id: A.27
function "rem" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(R'LENGTH-1 downto 0)
-- Result: Computes "L rem R" where L and R are UNSIGNED vectors.
-- Id: A.28
function "rem" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(R'LENGTH-1 downto 0)
-- Result: Computes "L rem R" where L and R are SIGNED vectors.
-- Id: A.29
function "rem" (L: UNSIGNED; R: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Computes "L rem R" where L is an UNSIGNED vector and R is a
-- non-negative INTEGER.
-- If NO_OF_BITS(R) > L'LENGTH, result is truncated to L'LENGTH.
-- Id: A.30
function "rem" (L: NATURAL; R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(R'LENGTH-1 downto 0)
-- Result: Computes "L rem R" where R is an UNSIGNED vector and L is a
-- non-negative INTEGER.
-- If NO_OF_BITS(L) > R'LENGTH, result is truncated to R'LENGTH.
-- Id: A.31
function "rem" (L: SIGNED; R: INTEGER) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Computes "L rem R" where L is SIGNED vector and R is an INTEGER.
-- If NO_OF_BITS(R) > L'LENGTH, result is truncated to L'LENGTH.
-- Id: A.32
function "rem" (L: INTEGER; R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(R'LENGTH-1 downto 0)
-- Result: Computes "L rem R" where R is SIGNED vector and L is an INTEGER.
-- If NO_OF_BITS(L) > R'LENGTH, result is truncated to R'LENGTH.
--===========================================================================
--
-- NOTE: If second argument is zero for "mod" operator, a severity level
-- of ERROR is issued.
-- Id: A.33
function "mod" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(R'LENGTH-1 downto 0)
-- Result: Computes "L mod R" where L and R are UNSIGNED vectors.
-- Id: A.34
function "mod" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(R'LENGTH-1 downto 0)
-- Result: Computes "L mod R" where L and R are SIGNED vectors.
-- Id: A.35
function "mod" (L: UNSIGNED; R: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Computes "L mod R" where L is an UNSIGNED vector and R
-- is a non-negative INTEGER.
-- If NO_OF_BITS(R) > L'LENGTH, result is truncated to L'LENGTH.
-- Id: A.36
function "mod" (L: NATURAL; R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(R'LENGTH-1 downto 0)
-- Result: Computes "L mod R" where R is an UNSIGNED vector and L
-- is a non-negative INTEGER.
-- If NO_OF_BITS(L) > R'LENGTH, result is truncated to R'LENGTH.
-- Id: A.37
function "mod" (L: SIGNED; R: INTEGER) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Computes "L mod R" where L is a SIGNED vector and
-- R is an INTEGER.
-- If NO_OF_BITS(R) > L'LENGTH, result is truncated to L'LENGTH.
-- Id: A.38
function "mod" (L: INTEGER; R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(R'LENGTH-1 downto 0)
-- Result: Computes "L mod R" where L is an INTEGER and
-- R is a SIGNED vector.
-- If NO_OF_BITS(L) > R'LENGTH, result is truncated to R'LENGTH.
--===========================================================================
-- Comparison Operators
--===========================================================================
-- Id: C.1
function ">" (L, R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L > R" where L and R are UNSIGNED vectors possibly
-- of different lengths.
-- Id: C.2
function ">" (L, R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L > R" where L and R are SIGNED vectors possibly
-- of different lengths.
-- Id: C.3
function ">" (L: NATURAL; R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L > R" where L is a non-negative INTEGER and
-- R is an UNSIGNED vector.
-- Id: C.4
function ">" (L: INTEGER; R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L > R" where L is a INTEGER and
-- R is a SIGNED vector.
-- Id: C.5
function ">" (L: UNSIGNED; R: NATURAL) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L > R" where L is an UNSIGNED vector and
-- R is a non-negative INTEGER.
-- Id: C.6
function ">" (L: SIGNED; R: INTEGER) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L > R" where L is a SIGNED vector and
-- R is a INTEGER.
--===========================================================================
-- Id: C.7
function "<" (L, R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L < R" where L and R are UNSIGNED vectors possibly
-- of different lengths.
-- Id: C.8
function "<" (L, R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L < R" where L and R are SIGNED vectors possibly
-- of different lengths.
-- Id: C.9
function "<" (L: NATURAL; R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L < R" where L is a non-negative INTEGER and
-- R is an UNSIGNED vector.
-- Id: C.10
function "<" (L: INTEGER; R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L < R" where L is an INTEGER and
-- R is a SIGNED vector.
-- Id: C.11
function "<" (L: UNSIGNED; R: NATURAL) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L < R" where L is an UNSIGNED vector and
-- R is a non-negative INTEGER.
-- Id: C.12
function "<" (L: SIGNED; R: INTEGER) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L < R" where L is a SIGNED vector and
-- R is an INTEGER.
--===========================================================================
-- Id: C.13
function "<=" (L, R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L <= R" where L and R are UNSIGNED vectors possibly
-- of different lengths.
-- Id: C.14
function "<=" (L, R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L <= R" where L and R are SIGNED vectors possibly
-- of different lengths.
-- Id: C.15
function "<=" (L: NATURAL; R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L <= R" where L is a non-negative INTEGER and
-- R is an UNSIGNED vector.
-- Id: C.16
function "<=" (L: INTEGER; R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L <= R" where L is an INTEGER and
-- R is a SIGNED vector.
-- Id: C.17
function "<=" (L: UNSIGNED; R: NATURAL) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L <= R" where L is an UNSIGNED vector and
-- R is a non-negative INTEGER.
-- Id: C.18
function "<=" (L: SIGNED; R: INTEGER) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L <= R" where L is a SIGNED vector and
-- R is an INTEGER.
--===========================================================================
-- Id: C.19
function ">=" (L, R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L >= R" where L and R are UNSIGNED vectors possibly
-- of different lengths.
-- Id: C.20
function ">=" (L, R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L >= R" where L and R are SIGNED vectors possibly
-- of different lengths.
-- Id: C.21
function ">=" (L: NATURAL; R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L >= R" where L is a non-negative INTEGER and
-- R is an UNSIGNED vector.
-- Id: C.22
function ">=" (L: INTEGER; R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L >= R" where L is an INTEGER and
-- R is a SIGNED vector.
-- Id: C.23
function ">=" (L: UNSIGNED; R: NATURAL) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L >= R" where L is an UNSIGNED vector and
-- R is a non-negative INTEGER.
-- Id: C.24
function ">=" (L: SIGNED; R: INTEGER) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L >= R" where L is a SIGNED vector and
-- R is an INTEGER.
--===========================================================================
-- Id: C.25
function "=" (L, R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L = R" where L and R are UNSIGNED vectors possibly
-- of different lengths.
-- Id: C.26
function "=" (L, R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L = R" where L and R are SIGNED vectors possibly
-- of different lengths.
-- Id: C.27
function "=" (L: NATURAL; R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L = R" where L is a non-negative INTEGER and
-- R is an UNSIGNED vector.
-- Id: C.28
function "=" (L: INTEGER; R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L = R" where L is an INTEGER and
-- R is a SIGNED vector.
-- Id: C.29
function "=" (L: UNSIGNED; R: NATURAL) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L = R" where L is an UNSIGNED vector and
-- R is a non-negative INTEGER.
-- Id: C.30
function "=" (L: SIGNED; R: INTEGER) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L = R" where L is a SIGNED vector and
-- R is an INTEGER.
--===========================================================================
-- Id: C.31
function "/=" (L, R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L /= R" where L and R are UNSIGNED vectors possibly
-- of different lengths.
-- Id: C.32
function "/=" (L, R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L /= R" where L and R are SIGNED vectors possibly
-- of different lengths.
-- Id: C.33
function "/=" (L: NATURAL; R: UNSIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L /= R" where L is a non-negative INTEGER and
-- R is an UNSIGNED vector.
-- Id: C.34
function "/=" (L: INTEGER; R: SIGNED) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L /= R" where L is an INTEGER and
-- R is a SIGNED vector.
-- Id: C.35
function "/=" (L: UNSIGNED; R: NATURAL) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L /= R" where L is an UNSIGNED vector and
-- R is a non-negative INTEGER.
-- Id: C.36
function "/=" (L: SIGNED; R: INTEGER) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Computes "L /= R" where L is a SIGNED vector and
-- R is an INTEGER.
--===========================================================================
-- Shift and Rotate Functions
--===========================================================================
-- Id: S.1
function SHIFT_LEFT (ARG: UNSIGNED; COUNT: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(ARG'LENGTH-1 downto 0)
-- Result: Performs a shift-left on an UNSIGNED vector COUNT times.
-- The vacated positions are filled with Bit '0'.
-- The COUNT leftmost bits are lost.
-- Id: S.2
function SHIFT_RIGHT (ARG: UNSIGNED; COUNT: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(ARG'LENGTH-1 downto 0)
-- Result: Performs a shift-right on an UNSIGNED vector COUNT times.
-- The vacated positions are filled with Bit '0'.
-- The COUNT rightmost bits are lost.
-- Id: S.3
function SHIFT_LEFT (ARG: SIGNED; COUNT: NATURAL) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0)
-- Result: Performs a shift-left on a SIGNED vector COUNT times.
-- The vacated positions are filled with Bit '0'.
-- The COUNT leftmost bits, except ARG'LEFT, are lost.
-- Id: S.4
function SHIFT_RIGHT (ARG: SIGNED; COUNT: NATURAL) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0)
-- Result: Performs a shift-right on a SIGNED vector COUNT times.
-- The vacated positions are filled with the leftmost bit, ARG'LEFT.
-- The COUNT rightmost bits are lost.
--===========================================================================
-- Id: S.5
function ROTATE_LEFT (ARG: UNSIGNED; COUNT: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(ARG'LENGTH-1 downto 0)
-- Result: Performs a rotate-left of an UNSIGNED vector COUNT times.
-- Id: S.6
function ROTATE_RIGHT (ARG: UNSIGNED; COUNT: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(ARG'LENGTH-1 downto 0)
-- Result: Performs a rotate-right of an UNSIGNED vector COUNT times.
-- Id: S.7
function ROTATE_LEFT (ARG: SIGNED; COUNT: NATURAL) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0)
-- Result: Performs a logical rotate-left of a SIGNED vector COUNT times.
-- Id: S.8
function ROTATE_RIGHT (ARG: SIGNED; COUNT: NATURAL) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0)
-- Result: Performs a logical rotate-right of a SIGNED vector COUNT times.
--===========================================================================
-----------------------------------------------------------------------------
-- Note : Function S.9 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: S.9
function "sll" (ARG: UNSIGNED; COUNT: INTEGER) return UNSIGNED;
-- Result subtype: UNSIGNED(ARG'LENGTH-1 downto 0)
-- Result: SHIFT_LEFT(ARG, COUNT)
-----------------------------------------------------------------------------
-- Note : Function S.10 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: S.10
function "sll" (ARG: SIGNED; COUNT: INTEGER) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0)
-- Result: SHIFT_LEFT(ARG, COUNT)
-----------------------------------------------------------------------------
-- Note : Function S.11 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: S.11
function "srl" (ARG: UNSIGNED; COUNT: INTEGER) return UNSIGNED;
-- Result subtype: UNSIGNED(ARG'LENGTH-1 downto 0)
-- Result: SHIFT_RIGHT(ARG, COUNT)
-----------------------------------------------------------------------------
-- Note : Function S.12 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: S.12
function "srl" (ARG: SIGNED; COUNT: INTEGER) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0)
-- Result: SIGNED(SHIFT_RIGHT(UNSIGNED(ARG), COUNT))
-----------------------------------------------------------------------------
-- Note : Function S.13 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: S.13
function "rol" (ARG: UNSIGNED; COUNT: INTEGER) return UNSIGNED;
-- Result subtype: UNSIGNED(ARG'LENGTH-1 downto 0)
-- Result: ROTATE_LEFT(ARG, COUNT)
-----------------------------------------------------------------------------
-- Note : Function S.14 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: S.14
function "rol" (ARG: SIGNED; COUNT: INTEGER) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0)
-- Result: ROTATE_LEFT(ARG, COUNT)
-----------------------------------------------------------------------------
-- Note : Function S.15 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: S.15
function "ror" (ARG: UNSIGNED; COUNT: INTEGER) return UNSIGNED;
-- Result subtype: UNSIGNED(ARG'LENGTH-1 downto 0)
-- Result: ROTATE_RIGHT(ARG, COUNT)
-----------------------------------------------------------------------------
-- Note : Function S.16 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: S.16
function "ror" (ARG: SIGNED; COUNT: INTEGER) return SIGNED;
-- Result subtype: SIGNED(ARG'LENGTH-1 downto 0)
-- Result: ROTATE_RIGHT(ARG, COUNT)
--===========================================================================
-- RESIZE Functions
--===========================================================================
-- Id: R.1
function RESIZE (ARG: SIGNED; NEW_SIZE: NATURAL) return SIGNED;
-- Result subtype: SIGNED(NEW_SIZE-1 downto 0)
-- Result: Resizes the SIGNED vector ARG to the specified size.
-- To create a larger vector, the new [leftmost] bit positions
-- are filled with the sign bit (ARG'LEFT). When truncating,
-- the sign bit is retained along with the rightmost part.
-- Id: R.2
function RESIZE (ARG: UNSIGNED; NEW_SIZE: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(NEW_SIZE-1 downto 0)
-- Result: Resizes the UNSIGNED vector ARG to the specified size.
-- To create a larger vector, the new [leftmost] bit positions
-- are filled with '0'. When truncating, the leftmost bits
-- are dropped.
--===========================================================================
-- Conversion Functions
--===========================================================================
-- Id: D.1
function TO_INTEGER (ARG: UNSIGNED) return NATURAL;
-- Result subtype: NATURAL. Value cannot be negative since parameter is an
-- UNSIGNED vector.
-- Result: Converts the UNSIGNED vector to an INTEGER.
-- Id: D.2
function TO_INTEGER (ARG: SIGNED) return INTEGER;
-- Result subtype: INTEGER
-- Result: Converts a SIGNED vector to an INTEGER.
-- Id: D.3
function TO_UNSIGNED (ARG, SIZE: NATURAL) return UNSIGNED;
-- Result subtype: UNSIGNED(SIZE-1 downto 0)
-- Result: Converts a non-negative INTEGER to an UNSIGNED vector with
-- the specified size.
-- Id: D.4
function TO_SIGNED (ARG: INTEGER; SIZE: NATURAL) return SIGNED;
-- Result subtype: SIGNED(SIZE-1 downto 0)
-- Result: Converts an INTEGER to a SIGNED vector of the specified size.
--===========================================================================
-- Logical Operators
--===========================================================================
-- Id: L.1
function "not" (L: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Termwise inversion
-- Id: L.2
function "and" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Vector AND operation
-- Id: L.3
function "or" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Vector OR operation
-- Id: L.4
function "nand" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Vector NAND operation
-- Id: L.5
function "nor" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Vector NOR operation
-- Id: L.6
function "xor" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Vector XOR operation
-----------------------------------------------------------------------------
-- Note : Function L.7 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: L.7
function "xnor" (L, R: UNSIGNED) return UNSIGNED;
-- Result subtype: UNSIGNED(L'LENGTH-1 downto 0)
-- Result: Vector XNOR operation
-- Id: L.8
function "not" (L: SIGNED) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Termwise inversion
-- Id: L.9
function "and" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Vector AND operation
-- Id: L.10
function "or" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Vector OR operation
-- Id: L.11
function "nand" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Vector NAND operation
-- Id: L.12
function "nor" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Vector NOR operation
-- Id: L.13
function "xor" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Vector XOR operation
-----------------------------------------------------------------------------
-- Note : Function L.14 is not compatible with VHDL 1076-1987. Comment
-- out the function (declaration and body) for VHDL 1076-1987 compatibility.
-----------------------------------------------------------------------------
-- Id: L.14
function "xnor" (L, R: SIGNED) return SIGNED;
-- Result subtype: SIGNED(L'LENGTH-1 downto 0)
-- Result: Vector XNOR operation
--===========================================================================
-- Edge Detection Functions
--===========================================================================
-- Id: E.1
function RISING_EDGE (signal S: BIT) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Returns TRUE if an event is detected on signal S and the
-- value changed from a '0' to a '1'.
-- Id: E.2
function FALLING_EDGE (signal S: BIT) return BOOLEAN;
-- Result subtype: BOOLEAN
-- Result: Returns TRUE if an event is detected on signal S and the
-- value changed from a '1' to a '0'.
end NUMERIC_BIT;
Reference in New Issue View Git Blame Copy Permalink