A few fails while parsing ivtest in the sv-tests environment

[caryr]

I noticed sv-parser does an excellent job of parsing most of the code in the sv-tests test bench (https://github.com/SymbiFlow/sv-tests). While working to get ivtest clean I noticed there are a few of our test that sv-parser is failing. One actually looks like a crash. If you were not aware of this TB I wanted to let you know. As one of the developers on Icarus Verilog I am interested in getting it and our regressions as clean as possible. This includes finding things we may have done incorrectly in our regressions so when I see a tool that is parsing most thing I want to know if it is something at our end our a miss on your end. Unfortunately the output they are showing does not indicate why the parse is failing so it's hard for me to know what the issue is.

[dalance]

Thank you for your information!
I checked the failed cases.

• br_gh330.v
  This is caused by huge nested expression.
  I'll consider the way to fix it.

• escaped_macro_name.v, pr1758122.v
  They are bugs of parser, and have been fixed.

• sv_queue_real.v, sv_queue_string.v, sv_queue_vec.v
  This is caused by '{}.
  In my understanding, empty '{} is not allowed according to LRM:

pattern ::=
. variable_identifier
| .*
| constant_expression
| tagged member_identifier [ pattern ]
| '{ pattern { , pattern } }
| '{ member_identifier : pattern { , member_identifier : pattern } }
assignment_pattern ::=
'{ expression { , expression } }
| '{ structure_pattern_key : expression { , structure_pattern_key : expression } }
| '{ array_pattern_key : expression { , array_pattern_key : expression } }
| '{ constant_expression { expression { , expression } } }
assignment_pattern_net_lvalue ::=
'{ net_lvalue {, net_lvalue } }
assignment_pattern_variable_lvalue ::=
'{ variable_lvalue {, variable_lvalue } }

• wiresl2.v
  This is caused by non-ASCII comment ( it is seems to be iso-8859-1? ):

out=01Àëÿ¿a^[[?1;2c$

sv-parser can parse UTF-8 only. I think this is a reasonable restriction because comment should be ASCII in LRM:

comment_text ::= { Any_ASCII_character }

[caryr]

Thank you for looking into this.

We have recently become aware of '{} being invalid and are trying to understand how to rewrite tests etc. to remove it along with fixes to the Icarus parser. I can add those to the sv-tests exclusion list for now.

Yes, I assumed it was the non-ASCII text. Thanks for verifying. Not sure what to do about that. I think many of our users appreciate this functionality. I will exclude this for now as well.

[caryr]

FYI '{} is supported by commercial tools (e.g. VCS). I opened an item to discuss how to handle these de facto standard items in sv-tests the other day.

[caryr]

Adding br_gh435.v as another unexpected fail which we recently added to ivtest. It has an embedded single line comment in a macro. I think there is some ambiguity in the standard around this though it is supported by commercial tools.

Cary

[dalance]

I fixed the embedded single line comment issue.