robtaylor / iroha

Intermediate Representation Of Hardware Abstraction (LLVM-ish for HLS)

Iroha: Intermediate Representation Of Hardware Abstraction

Author: Yusuke TABATA ([e-mail]) and the team (TBD)

TL;DR: Aiming to be LLVM for HLS

What's this?

Iroha is a text representation of a network of state machines and tools to process it. The representation uses S-expression to describe a network of state machines. It looks like as follows:

(MODULE ...
  (TABLE
    (REGISTERS (REGISTER ...) (REGISTER ...) ...)
    (RESOURCES (RESOURCE ...) (RESOURCE ...) ...)
    (STATE (INSN ...) (INSN ...) ...))
  (TABLE ...))

A TABLE denotes a state machine. It can have its behavior including calculation , communication to other TABLEs and so on.

Build and use

(0) First of all, build the binary.

Requirements:
C++11 capable compiler: g++ or clang++.
Build tools: make and gyp.

> $ ./configure ; make

(1) Try to read Iroha IR in S-expression and just dump it.

> $ ./iroha tests/min.iroha
(or
> $ ./iroha -v tests/min.iroha
to get verilog output)

(2) Example to generate Verilog from Python examples.

> $ cd examples
> $ python loop.py | ../iroha - -v -o loop.v
> (or other .py files)

(3) Example to use optimizers

> $ ./examples/xorshift | ./iroha - -opt wire_insn,clean_empty_state,clean_unreachable_state | ./iroha - -v -o /tmp/xorshift.v

Please read src/iroha/iroha.h, src/iroha/iroha_main.cpp examples/ for more details.

Source tree

• src/
  • Libraries and commands.
• src/builder
  • Code to build Iroha data structures.
• src/design
  • Code to manipulate design IR.
• src/iroha
  • Public header files of libraries manipulate on Iroha data structures.
  • Basic API layer code.
• src/opt
  • Optimizers
• src/writer
  • Code to write design IR as a file.
• tests/
  • Test input.

TODOs

• P1: Connect FIFO to a dataflow table.
• P2: FPGA style coding style (e.g. register initialization)
• P2: I/O for embedded verilog module
• P2: Simplify wait cycle if there's 1 multi cycle insn in a state
• P2: Set reset polarity to embedded module.
• P2: Allow multiple embedded module instances.
• Usability: Document
• Usability: More debug output from optimizers.
• Usability: Export optimizer API so that users can add own pass
• Dev: Migrate from unmaintained gyp build.
• Q: Do we need instance/module separation?
• AXI: Allow or fail to attach both master/slave to an array.
• AXI: Ability to merge channels.

Authors and friends

• Takefumi Miyoshi (miyo)
• Shinya Takamaeda-Yamazaki (shtaxxx)
• Ichiro Kawazome (ikwzm) and
• Yusuke Tabata (yt76)

-- format this document

$ markdown README.md > README.html