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Language Change Specification for Updated reference IEEE Standards

LCS Number:	LCS-2016-IEEEStdUpdates
Version:	2
Date:	30-Mar-2017
Status:	Approved
Author:	Patrick Lehmann
Summary:	Updating the IEEE Std references.

Language Change Specification for Updated reference IEEE Standards

Voting Results:

Yes:

Steve Grout - 2017-03-27 - ver 1
Martin Thompson - 2017-03-27 - ver 1 (see comment about typo)
Patrick Lehmann - 2017-03-30 - ver 2
Jim Lewis - 2017-03-30 - ver 2
Rob Gaddi - 2017-03-30 - ver 2
Lieven Lemiengre - 2017-03-30 - ver 2

No:

Abstain:

Style Notes

Changes are shown in red font.
Deletions are ~~crossed out~~.
Restructuring is shown in crossed out ~~gray font~~ somewhere else in gray font.
Editing or reviewing notes in green font.

Revisions

Version 2: 30-Mar-2017

Deleted "Annex E" entirely

Version 1: 27-Mar-2017

Fixed IEEE Std 754-1985 -> 754-2008
Fixed IEEE Std 854-1987 -> deleted, subsumed by 754-2008
Fixed IEEE Std 1076.6 -> deleted, withdrawn

Details of Language Change

2. Normative references

IEEE Std 754^TM-2008 ~~1985 (Reaff 1990)~~, IEEE Standard for ~~Binary~~ Floating-Point Arithmetic.^{3, 4}

~~IEEE Std 854^TM -1987 (Reaff 1994), IEEE Standard for Radix-Independent Floating-Point Arithmetic~~

5.2.5.1 General (Floating-point types)

An implementation shall choose a representation for all floating-point types except for universal_real that conforms ~~either~~ to IEEE Std 754-2008~~1985 or to IEEE Std 854-1987~~; ~~in either case,~~ a minimum representation size of 64 bits is required for this chosen representation.

6.5.2 Interface object declarations

NOTE 3 - Ports of mode linkage are used in the Boundary Scan Description Language (see IEEE Std 1149.1TM-2013 ~~2001~~ [B15]).

16.8.1.1 Scope (Standard synthesis packages)

~~Further related standard practices for synthesis of register-transfer level digital circuits are specified in IEEE Std 1076.6-2004 [B14].~~

Changes from IEEE Std 1076-2002 (Annex E)

This section is deleted in its entirety.

G.5.2 Use model

The package includes a number of functions recommended by IEEE Std 754-2008 ~~1985 and IEEE Std 854-1987~~. They are described in G.5.4.4.

G.5.4.2 Functions

sqrt	Square root. Inputs: arg: float; round_style: round_type; guard: NATURAL; check_error: BOOLEAN; denormalize: BOOLEAN. Returns the square root of arg, as defined by IEEE Std 754-2008 ~~1985~~.

G.5.4.3 Conversion functions

classfp	Find the classification of a floating-point number. Inputs: arg (float). Returns a value of the type valid_fpstate. Note that IEEE Std 754-2008 ~~1985 and IEEE Std 854-1987~~ recommendss the name ?class? for this function. However, the floating-point package calls the function ?classfp? to avoid conflict with ?class? as a reserved word in a future extension of VHDL.

classfp

Find the classification of a floating-point number. Inputs: arg (float). Returns a value of the type valid_fpstate. Note that IEEE Std 754-2008 ~~1985 and IEEE Std 854-1987~~ recommendss the name ?class? for this function. However, the floating-point package calls the function ?classfp? to avoid conflict with ?class? as a reserved word in a future extension of VHDL.

Glossary (Annex I)

chosen implementation: An implementation of floating-point types that conforms to ~~either~~ IEEE Std 754-2008 ~~1985 or to IEEE Std 854-1987~~ and with a minimum representation size of 64 bits. (5.2.5.1)

[...]

floating-point types: A scalar type whose values approximate real numbers. The representation of a floating-point type conforms ~~either~~ IEEE Std 754-2008 ~~1985 or to IEEE Std 854-1987~~ and has a minimum size of 64 bits. (5.2.1, 5.2.5)

Bibliography (Annex J)

~~[B14] IEEE Std 1076.6TM-2004, IEEE Standard for VHDL Register-Transfer Level (RTL) Synthesis.~~

[B15] IEEE Std 1149.1TM-2013 ~~2001~~, IEEE Standard Test Access Port and Boundary Scan Architecture.

Comments

Version 1

It seems that G5.4.3 has an extra red "s" in "recommends"

-- Martin Thompson - 2017-03-28

In "Changes from IEEE Std 1076-2008 2002 (Annex E)" the first line: "This annex lists those clauses that have been changed from IEEE Std 1076-2002, during its revision." should be: "This annex lists those clauses that have been changed from IEEE Std 1076-2008, during its revision."

-- Pablo2 Blecua - 2017-03-28

Oh, and copying from PDF introduced some ? signs ...

-- Patrick Lehmann - 2017-03-28

Topic revision: r8 - 2017-04-02 - 16:28:19 - PatrickLehmann

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