With the Verilog vs. VHDL war now over with the merging of Open Verilog International and VHDL International into Accellera, EDA companies were jockeying for position ahead of a possible C/C++ rivalry between the Open SystemC Initiative and Accellera. But they could still move back from the brink if talks between the major EDA vendors lead to a merger of the initiatives.

Cadence Design Systems Inc. (San Jose, Calif.) claimed it was neutral on language matters but announced it was satisfied with changes in the organization of the Open SystemC Initiative and so is joining a newly expanded steering group. But according to Serge Leef, general manager of the system-chip verification business unit at Mentor Graphics Corp. (Wilsonville, Ore.), Mentor has told Synopsys Inc. (Mountain View, Calif.) that it wants six other organizational changes before it will put its weight behind the initiative.

Meanwhile, other players such as CynApps Inc. (Santa Clara, Calif.) are working on a rival C/C++-class library initiative coming out of Accellera that is tied to its Semantic Reference Manual (SRM) initiative.

SystemC is a C++-class library system, available without charge under an open community license, designed to help make C suitable for hardware design from a system level. So far it has been built around key contributions from Synopsys, CoWare Inc. (San Jose) and Frontier Design NV (Leuven, Belgium).

Big-shot backers

SystemC is backed by a number of major system and semiconductor houses — EDA tools users including ARM, Ericsson, Fujitsu, Infineon, Lucent, Sony, STMicroelectronics and Texas Instruments. They have now been joined by Cadence, Motorola and NEC.

Even as Cadence was announcing support for SystemC, Accellera announced that it too would standardize a C/C++ language for high-level design. Accellera said it had decided to create a task force to define an example C++-class library and had called for technical contributions from interested parties. The task force is being created as a subcommittee of the Accellera Architectural Language Committee (ALC); the library would serve as an example implementation within its SRM.

"The concept of C/C++-based design methodologies is starting to gain acceptance among leading systems companies," said Dennis Brophy, co-chairman of the Accellera unification committee and director of strategic business development at Model Technology Inc. "The need for an open and inclusive standard in this area has been growing for some time. We are going to capitalize on contributions from the industry to jump-start this activity."

John Sanguinetti, president of CynApps, which has a proprietary C++-class library that it provides free, said he would offer his technology to Accellera. He added that he also expected C Level Design Inc., Co-Design Automation Inc., Mentor and others to get involved with the standards effort.

The Accellera ALC group is setting up a June 27 meeting to review initial technology contributions. The group said it believes that no single vendor has all the technology necessary to support next-generation system design, and by working together the group can develop it at an unprecedented pace.

While C Level Design offers tools to help design from a C-language starting point, Co-Design has developed a language called Superlog that combines language constructs of Verilog and C. It is to be put into the public domain later this year.

Simon Davidmann, president and chief executive officer of Co-Design (San Jose), said his company would cooperate with Accellera but that it was also cooperating with Open SystemC. "We have a little bit of C++ technology in our SystemSim simulator so, yes, we will participate in Accellera," he said. "But C/C++ is going to be an exemplar as an appendix to the SRM. There's also going to be Java, C/C++ and Superlog references."

Speaking at a SystemC Users Forum at DAC, Stan Krolikoski, vice president of marketing at Cadence's systems-level design group, said, "There's always been a lack of cooperation [in the EDA industry] and it culminated in the HDL wars. We don't want to see that happen again."

Krolikoski said that while the SystemC language was not yet complete, "a true system language will help everybody. I do believe Open SystemC is becoming an open dynamic group that can do the standard."

One language

However, Cadence is also a participant within Accellera. "I will be suggesting that SystemC could be an exemplar of the SRM," Krolikoski said. "I will work toward there being one C/C++ language."

Elsewhere within the Open SystemC organization there seemed to be less enthusiasm for Accellera's initiative. Kevin Kranen, director of strategic programs for Synopsys and co-chairman of the Open SystemC Initiative, said the group needed to examine what Accellera is trying to do.

If Accellera is prepared to rubber-stamp SystemC-class library versions as they came out of Open SystemC then maybe the two could work together. "It all depends on whether they are trying to create convergence or divergence," Kranen said.

Mentor's support

Meanwhile, Mentor backs the Accellera initiative. "We believe in open-source standards and we think that Accellera is a good vehicle for developing [them]," said Mentor's Leef.

Leef said Synopsys did make an offer to Mentor and Cadence to modify the Open SystemC organization's by-laws to allow both to review the relevant technical documentation. He said Brian Bailey and Michael Bohm, Mentor's two chief scientific officers, reviewed the SystemC technology and concluded it was technically deficient.

"We looked at the by-laws to see if the organization allowed the technical deficiencies to be addressed. But we found the by-laws were deficient as well," said Leef. He said he has asked for changes in the by-laws.

Certain of the proposed changes are in the details of voting procedures that Mentor feels give Synopsys veto power. But the most controversial objection concerns patent rights.

"We want Synopsys to indemnify users and extenders of SystemC with respect to all C language synthesis patents held by Synopsys, CoWare and Frontier," said Leef.