Updated terminology:

• IR0 relation .rel -> IR0+ circuit
• IR0 instance .ins -> IR0+ public_input
• IR0 short witness .wit -> IR0+ private_input

Since we're not using any of the looping constructs or plugins yet, we're able to transform the Tiny86 NOP IR0 .rel into an IR0+-conformant circuit with string substitution. sed commands that accomplish this are below. NB: our NOP circuit does not use initial register file state, so we didn't need to substitute instance with public():

sed -i 's/short_witness/private()/g' ~/tiny86.rel
sed -i 's/@and/@mul/g' ~/tiny86.rel
sed -i 's/@xor/@add/g' ~/tiny86.rel
sed -i 's/@not(\(\$[0-9]\+\))/@addc(\1, <1>)/g' ~/tiny86.rel

Other changes:

• For the first line of all the files, change version-1.0.0 to version-2.0.0-beta
• The second line of the file is the resource type (circuit, public_input, private_input) followed by ;
• Fields used by the circuit (zero-indexed) start in the third line of the file. For our purposes, IR0 field characteristic 2 degree 1 -> IR0+ @type field 2.
  • Right now, we only emit field-switching gates when targeting the reverie backend, so we can omit indices from private([field_index]) and public([field_index]), but if we were to transform circuits including multiple fields, we'd need to calculate {characteristic}^{degree} to perform the substitution correctly.

For targets that require a fully inlined circuit, yosys itself can perform complete inlining. See: https://yosyshq.readthedocs.io/projects/yosys/en/latest/cmd/flatten.html

For targets with function calls (like the primary IR0+), a non-flattened circuit with @functions at module boundaries could yield more efficient circuits at verification time.

See #32 failing build: we're (as of writing) 2 major versions out of sync and as a result are calling some seemingly deprecated APIs.

rust nightly versions newer than approx. 2022-11-01 fail to compile;

error[E0310]: the parameter type `T` may not live long enough
   --> src/generic/circuit.rs:795:21
    |
795 |     type IntoIter = impl Iterator<Item = Operation<T>>;
    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `mcircuit::Operation<T>` will meet its required lifetime bounds
    |
help: consider adding an explicit lifetime bound...
    |
790 | impl<'a, T: 'a + WireValue + 'static> IntoIterator for &'a GenericCircuit<T>
    |                            +++++++++

For more information about this error, try `rustc --explain E0310`.
error: could not compile `sv_circuit` due to 3 previous errors

for now pinning rust compiler to a known good nightly in default.nix and using nix-shell --pure --run "cargo build". however, this annoying and likely to confuse anyone reasonably using 'bare' cargo build.