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********************* IBIS GOLDEN PARSER BUG REPORT FORM *********************
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INSTRUCTIONS
 
To report a bug in the IBIS golden parser.  Please fill out the top part
of the following form and send the complete form to info@ibis.org.
 
A list of reported bugs is maintained at http://ibis.org/bugs/ibischk/ .
 
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PARSER VERSION NUMBER: 7.0.2
 
PLATFORM (SPARC, HP700, PC, etc.): PC
 
OS AND VERSION: Microsoft Windows 10
 
REPORTED BY: Michael Mirmak, Intel Corp.
 
DATE: April 15, 2021
 
DESCRIPTION OF BUG:
 
The IBIS 7.0 specification states, for Type UI, that "UI parameter values are 
in units of UI (bit time). The parameter may take on either floating point or 
integer values."
 
In addition, for Format List, the specification states that "the first 
value shall be assumed to be the default, if the optional selection Default
is not present. If the optional selection Default is used with List, the
argument to Default must be an explicit member of the List and will override
the use of the first List value as default (for example, (List 0 1 2 3 4)
implies that the default value for the List is 0, while (List 0 1 2 3 4)
Default 2) means that the default value for the List is 2, not 0)."

However, the definition of s floating point number includes a number with or
without a sign and a decimal point. A number such 1.0 and 1 are considered
equivalent.
 
What is not stated is whether the parser and EDA tools should evaluate any 
equivalence between integer and floating-point values for the purposes of 
checking that a List’s Default value is indeed provided as part of the List.  

Another way of stating this: should all the values of a given parameter, 
including Value and Default, use only floating-point values or only integers,
as opposed to mixing them?
 
In the example provided below, a parameter of Format List and Type UI shows 
combinations that mix integer and floting poiont values of 1 or 1.0  The
parser evaluates “1” and “1.0” as equivalent, without reporting a Note,
Warning, or Error.  This might be a problem in some tools where number types
are rigidly enforced.
 
The parser’s behavior is correct so long as the specification does not intend
to enforce a common format (integer or floating point) within any given 
parameter.

 
INSERT IBIS FILE DEMONSTRATING THE BUG:
 
(bug216

| Testing (Type UI) with (List *** ) with Float and Integer Numbers)

   (Reserved_Parameters
      (AMI_Version (Usage Info) (Type String) (Value "7.0"))   
      (Init_Returns_Impulse (Usage Info) (Type Boolean) (Default False))
      (GetWave_Exists (Usage Info) (Type Boolean) (Default True))
      (Rx_Clock_Recovery_Mean (Usage Info) (Type UI)
        (List -2 -1 0 1 2 3) (Default 1.0)
        (Description "Integers in List, Float in Default"))
      (Rx_Clock_Recovery_DCD (Usage Info) (Type UI)
        (List -2.0 -1.0 -0.0 1.0 2.0) (Default 1)
        (Description "Float in List, Integer in Default"))
      (Rx_Clock_Recovery_Dj (Usage Info) (Type UI)
        (List -5 -3 -1.5 -1.0 0 1 2 3.0 5) (Default 1.0)
        (Description "Mixing Floats and Integers in List, Float is Default"))
    ) 
)

 
The parser output (with the -ami and -caution flags) is shown below:
 
IBISCHK7 V7.0.2
 
... Checking bug216.ami for AMI Version 7.0 Compatibility...
 
Errors  : 0
 
File Passed
 
 
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******************** BELOW FOR ADMINISTRATION AND TRACKING *******************
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BUG NUMBER:  216
 
SEVERITY: [FATAL, SEVERE, MODERATE, ANNOYING, ENHANCEMENT]  ANNOYING
 
PRIORITY: [HIGH, MEDIUM, LOW]                               LOW
 
STATUS: [OPEN, CLOSED, WILL NOT FIX, NOT A BUG]             NOT A BUG
 
FIXED VERSION:
 
FIXED DATE: April 23, 2021
 
NOTES ON BUG FIX:
Classified on April 23, 2021 at the IBIS Open Forum Meeting
Resolved as NOT A BUG.  The mixed types are explicitly permitted.
However, we may insert a brief recommendation that for Float or UI, any
intergers be entered as floating point numbers to avoid any future issues
 
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