Vector Task Group minutes for 2021/02/05 meeting

Krste Asanovic

Date: 2021/02/05
Task Group: Vector Extension
Chair: Krste Asanovic
Vice-Chair: Roger Espasa
Number of Attendees: ~16
Current issues on github:

# Next Meeting

It was decided to meet again in two weeks (Feb 19) to allow time for
everyone to digest and comment on the v0.10 release version. Please
send PRs for any small typos and clarifications, and use mailing list
for larger issues.

Issues discussed

# Assembly synatx

There was a desire to move away from allowing vsetvl to imply
"undisturbed" behavior by default, to ensure maximum use of "agnostic"
by software. The assembler can issue errors instead of warnings when
the ta/tu/ma/mu fields are not explicitly given, with perhaps an
option to allow with a warning to allow older code to be compiled.

# Spec formatting

There was some discussion on use of Wavedrom formatting tools. New
tools to give diagrams for the register layout will be added. There
was also a promise of somewhat faster build times for the doc. There
apparently is a central flow for running document generation on
commits at, and we need to sync up with that process.

# Extend agnostic behavior of mask logical operations

There was a request to extend tail-agnostic behavior of mask logical
instructions to allow the tail to be overwritten with values
corresponding to the logical operation (as opposed to agnostic values
that currently can only be all 1s or the previous destination value).
This is a relaxation of requireements, so would not affect
compatibility of existing implementations. To be discussed.