SV-BC Meeting Date: Monday, April 11, 2011 Time: 9:00am-11:00am PDT Toll Free Dial In Number in North America: 1-888-813-5316 Caller Paid Dial In Number: 1-650-584-6338 Meeting ID: 45961 1211310202213101 Day 1844176285730629 0000001111000000 Month 4332112110998887 1111111111111111 Year 1111110000000000 aa-aa-a-a-aaaaa- Steven Sharp - Cadence aaaa-aaaaa-aaaaa Francoise Martinolle - Cadence -a-aaaaaaaaa--aa Kaiming Ho - Fraunhofer Institute aaaaaaaaaaaaaa-a Matt Maidment - Intel aaa-aaaaaaaaaa-a Tom Alsop - Intel aaaa-aaaaaaaaaaa Shalom Bresticker - Intel aaaaaaaaaaaaa-aa Dave Rich - Mentor Graphics aaaaaaa-aaaaaaaa Gordon Vreugdenhil - Mentor Graphics aa-aa-aaaaa-aa-a Alex Gran - Mentor Graphics aaaaaaaa-aaaaaaa Arnab Saha - Mentor Graphics a-a-aaa-aa-aa-aa Eric Coffin - Mentor Graphics aaaaaaaaaaaa-aaa Brad Pierce - Synopsys aaaaaaaaaaaaaaaa Mark Hartoog - Synopsys -----a--------a- Greg Jaxon - Synopsys ---------------- Scott Little - Freescale ---------------- John Havlicek - Freescale ---aa------aaaaa Cliff Cummings - Sunburst Design ---aa-aaa--a--aa Heath Chambers - Consultant/Trainer ---aaaa-aa---aaa Don Mills - LCDM Engineering ---a-a---a-aa-aa Daniel Schostak - ARM ---aa-a--------- David Gates - AMD ---aaaa-a-aaa--a Peter Flake - Elda Technology ----aa-aaaaa---- Linc Jepson - 74ze ---------------- Rishiyur Nikhil - BlueSpec -----------a---a Jonathan Bromley - Verilab Agenda + Review IEEE patent policy http://standards.ieee.org/board/pat/pat-slideset.ppt Gord moves to consider it reviewed. Mark seconds. No opposed. No abstain. Motion passes. + Review previous meeting minutes http://www.eda.org/sv-bc/minutes/sv-bc_11_03_28.txt Tom moves to accept. Gord seconds. No opposed. Abstain: Eric (did not attend) Motion passes. + Mantis 1067 http://www.eda.org/svdb/view.php?id=1067 Postponed for a new proposal from Jonathan. + Mantis 2856 http://www.eda.org/svdb/view.php?id=2856 This discussion considered both 2856 and limiting hierarchical references for parameters in module instantiations Can we differentiate usage for design construction (e.g. parameter assignments, generate) and non-construction contexts? Can we define what works, what does not work, and what leads to an undefined result. Gord proposed: A hierarchical reference to a parameter is considered to be a constant expression if: a) the reference resolves in upwards manner and/or b) no downwards component of the name crosses a generate construct or arrayed instance. Concern that users will have difficulty understanding this rule. Building consensus that this is implementable and gives users some flexibility. Francoise introduced the concepts of procedural constant expressions ( invariant by the start of simulation) and structural constant expressions Mark noted that determining the type of the constant expression is a property of the design and cannot be computed locally. Steven responded that rules can be crafted to enable local determination. Believe this is significant work to get right. Bind may introduce some complexities. Mark suggests inverting defparam rule to cover hierarchical references in for constant expressions: Q: Should this cover data type and value parameters? A: Permit only hierarchical references to value parameters under restrictions Q: Should this cover hierarchical references to constant functions? A: Would like to forbid this. Q: Should this cover hierarchical references to enum literals? A: Yes. Consider these like value localparams. Q: Interface port "dot" parameter value A: Yes. Q: Interface port "dot" data type parameter A: No except in circumstance already permissible in LRM. Q: Do we want to address bind instances more fully (include them with other LRM references to limitations that apply to generate and arrayed instances). A: Yes. Q: Are virtual interface references to be lumped in with these? A: Should exclude these for now. Brad asked if we can remove the restrictions from constant variable assignments? General consensus is "yes". Gord agress to work on provide text to address restrictions on hierarchical referenecs (Mantis 2388). Remainder of items should be easy to add-on. + Mantis 210 Matt asked why not allow more or less ports based on parameterization? extern modules allow one to address binding and linking issues. interface ports of modules must be connected interfaces and generic interface allow one to sort of have this. Adding scope names to generate clarified how to handle/limit this. Would like something similar for this problem. Implementers concerned with this long-standing assumption in the language. If port is conditionally declared, can result in expressions that result in implicit net declaration that wants to be resolved at parse time. 11:00AM Steven moves to adjourn. -- Defer following to Email Vote -- + Mantis 2595 http://www.eda.org/svdb/view.php?id=2595 + Mantis 2976 http://www.eda.org/svdb/view.php?id=2976 + Mantis 2977 http://www.eda.org/svdb/view.php?id=2977 + Mantis 2982 http://www.eda.org/svdb/view.php?id=2982 + Mantis 3026 http://www.eda.org/svdb/view.php?id=3026 + Mantis 3062 http://www.eda.org/svdb/view.php?id=3062 + Mantis 3274 http://www.eda.org/svdb/view.php?id=3274 + Mantis 3362 http://www.eda.org/svdb/view.php?id=3362 Top 25 Mantis Items 696 - Complete 2310(1084, 1201) - Participants: Eric, Tom, Shalom, Steven, Wilson Snyder 3053 - Participants: Francoise, Mark, Alex, Kaiming 3055 - Participants: Gord, Mark 2991 - Champion: Tom, Participants: Steven 1566 - For future discussion 2114 - Similar to 3053. Have same group look at it. 210 - Participants: Shalom, Matt 3056 - Champion: Shalom, Participants: Steven, Francoise 1084 - Logical Expressions in Macros 2115 - X-Optimism/X-Pessimism resolution 3073 - Collected $bits issues 1697 - Macro Loops 1202 - Define Standard Preprocessor 1251 - X/Z behavior in various contexts 2289 - parameters inside comp unit & gen block are local 1504 - parameterized structs and unions 1144 - Out-of-bound array address 2081 - always_comb statements 1553 - nested module clarifications 2684 - variable part-selects 1861 - major modport enhancements 1523 - behavior of ?: on complex types 3074 - Connectivity Enhancements 2124 - `default_nettype var-type directive Action Items 03/28/11 Matt for April 11, 2011 meeting add 2856 and follow-up on Gord's proposal to limit hierarchical references for parameters in module instantiations. Outstanding 05/10/10 Matt create Master Issue for WG-approved SV-BC Top-25 07/19/10 Matt follow-up about voting rules for technical sub-committee. Is there a limit on the number of reps from 1 entity? 07/19/10 Dave to post request to reflectors for clarification of 2108 07/19/10 Jonathan post some items for discussion related to 2114 to reflector. 08/02/10 Brad give SV-BC feedback on Mantis 2992 to Mehdi 08/02/10 Eric start reflector thread on Mantis 2310 08/02/10 Gord meet F2F with Mark when in Bay Area 08/16/10 Matt to rethink 210 in terms of configuration and alias. 08/16/20 All send Shalom feedback about prioritizing the issues raised in port declaration issue summary: http://www.eda.org/sv-bc/hm/10498.html 09/13/10 Jonathan show simple examples of virtual interfaces, sub-interfaces and base classes in modules to demonstrate different methods for connecting design and testbenches. 09/27/10 Review Shalom's list of interface issues and suggest issues to tackle now. 05/10/10 Matt create Master Issue for WG-approved SV-BC Top-25 07/19/10 Matt follow-up about voting rules for technical sub-committee. Is there a limit on the number of reps from 1 entity? 07/19/10 Dave to post request to reflectors for clarification of 2108 07/19/10 Jonathan post some items for discussion related to 2114 to reflector. 08/02/10 Brad give SV-BC feedback on Mantis 2992 to Mehdi 08/02/10 Eric start reflector thread on Mantis 2310 08/16/20 All send Shalom feedback about prioritizing the issues raised in port declaration issue summary: http://www.eda.org/sv-bc/hm/10498.html 09/13/10 Jonathan show simple examples of virtual interfaces, sub-interfaces and base classes in modules to demonstrate different methods for connecting design and testbenches. 09/27/10 Review Shalom's list of interface issues and suggest issues to tackle now. 11/22/10 Brad to file Mantis item for upward passing of interfaces. 12/06/10 Matt open new Mantis item covering determination of port kind for .named_port connection (23.2.2.3). 01/31/11 All check with users regarding viability of rule that virtual interface declarations require that the referenced interface be previously parsed. 02/14/11 Users consider proposed restrictions and use-cases for varargs and provide feedback. 03/14/11 Matt talk to Karen about Accellera plans for participation. Questions about how to get user input, especially for bugs. 03/14/11 Matt check back with Gord and Mark in April about feedback regarding interface issues. 03/14/11 All drill down on 3055 and identify issues that would be straightforward to clarify regarding constant expressions, type operations and what is a hierarchical name. 03/14/11 Matt code examples for 210 and make proposal to resolve.