DevMeeting - 2021-07-12/13

[jackkoenig]

Outreach

• [jiuyang] CCC Shanghai
  • Editing video.
• [jiuyang] None resolved Q&A
• [jiuyang] Send calendar invites on the mailing list?

Updates

Pinned Items

• Priority PRs:
  • [jiuyang] Espresso Espresso Decoder #1964
    • Depends on refactor github action #2003 to pass CI.
    • Finished, ask for merging.
  • [jiuyang] Refactor CI and Tests, these PRs have dependencies.
    • Refactor tests #2004
      • Ask for help from in sbt.
        • This PR moves BasicTest etc infrastructure to chiselTest.
          • Chisel should not depends on Treadle
        • Thus no-plugin-test should depends on chisel3 / test
        • After adding 7687c1d
        • sbt will add the compiler plugin automatically from chisel project???
        • Tuned this for the whole weekend, and gave up.
    • Speed up tester with treadle. #2036
      • Really a speed up: from 30mins+ -> 8 mins
      • Blocked by Refactor tests #2004
  • Problematic naming bug with Cat Fix Cat rename signal #2010 #2011
    • Need response from .
  • Module with multiple memories have no readmem statements firrtl#2168: Annoying issue where Dedup breaks some Verilog customization annotations
    • Jared is working on this: Fix memory annotation deduplication firrtl#2286
  • [jiuyang] Multi-dimension IO connection bug.
    • Reported in 多维数组会导致IO的方向推断错误，这是不是一个bug?(Is it a bug that multidimensional arrays lead to incorrect inference of the direction of IO?) #2038

Discussion 1

• [chick] 2.13 odds and ends
  • Projects missing 2.13
    • github.com/sequencer/chipsalliance-playground
    • https://github.com/freechipsproject/chisel-testers
    • https://github.com/ucb-bar/dsptools
    • https://github.com/freechipsproject/diagrammer
      • Also needs to drop 2.11
    • Tip for anyone looking at this is to look at treadle PR for 2.13: Add support for Scala 2.13 treadle#290
• [jack] 3.4.4/1.4.4
  • Fix custom memory emission: Fix memory annotation deduplication firrtl#2286
• [jiuyang] prefer to using using system protoc and antlr4 in mill firrtl#2276
  • using system protobuf and antlr4 in the mill build system.
• [jiuyang] remove DefRegInit, change DefReg API with option definition. #1944: Unify Chisel internal IR of registers
  • Done
    • update for chipsalliance/chisel3#1944 freechipsproject/chisel-testers#318
    • update for chipsalliance/chisel3#1944 ucb-bar/chiseltest#332
• [jiuyang] Implement NoCommonSubexpressionElimination firrtl#2291
  • Resolve Can DeadCodeElimination, CommonSubexpressionElimination, ConstantPropagation, etc. be turned off ? #2006
• [jack] 3.5 Outstanding
  • Deprecate @chiselName
  • Should we deprecate not using the plugin?
    • Need to resolve
      • Enabling Chisel plugin side-effects & questions #1890
        • Plugin doesn’t do prefixing for non-Data subtypes but chiselName does
        • [jack] If resolution is “Won’t Fix”, then I think we should add “prefix” macro
          • val foo = prefix(“foo”) { … }
          • Could do ValName to have: val foo = prefix { … }
        • Another option is to add a “Prefixable” trait that user-defined types can implement
          • In @chiselName we had “DoNotPrefix”
          • Note that this means you can’t prefix Scala stdlib types (Tuple, List, etc.)
            • Could do a typeclass?
      • Autoclonetype 2 crashes on Bundles with higher-kinded type parameters #1893
      • Autoclonetype 2 supports bound hardware as fields of Bundles #1894
  • Deprecate firrtl-interpreter
  • DataView
  • InstanceAPI
  • Deprecate mutable methods in RenameMap (adding MutableRenameMap)
    • Annotation.update shouldn’t see a mutable type
    • Transforms can use MutableRenameMap, but annotations themselves are restricted to the lookup functions and should not be able to mutate the RenameMap
  • Delete deprecated stuff (can we get rid of Form?)
    • Last step of Dependency API migration
• [Adam] Instance API overview/feedback

Discussion 2

• [Adam] Instance API overview/feedback
  • Long discussion
  • @interface + @public annotations can generate extension methods for Instance[T], but unclear how this works if you want a common interface for instances of two different modules
• [jiuyang] CI goes faster Speed up CI #2043 :
  • Treadle is faster than Verilator in small cases:
    • ~30 mins -> ~8 mins
    • Still exists some Verilator cases.
  • GraalVM is faster than OpenJDK:
    • 7’21 -> 7’44
    • 9’26 -> 10’03
  • Mac failed with
    • Intel macOS Big Sur 11.4 make test fails: "ld: file too small (length=8) file 'Vt_a1_first_cc__ALL.a' for architecture x86_64" verilator/verilator#3031
    • Success in my M1
  • Result:
    • Switch to Treadle + GraalVM
    • But still use Verilator on push
  • Question:
    • Should we keep using OpenJDK as CI environment?