The MSRV is now 1.54.0, because reddsa 0.2.0 included a fix to its
nightly CI that inadvertently bumped its MSRV.
The `halo2` crate is now the `halo2_proofs` crate, but we're avoiding
the cross-repo crate rename until after `halo2_gadgets` is extracted.
This also brings in the 20% prover performance improvement from
zcash/halo2#447.
We change `CellValue` into a typedef of `AssignedCell` to simplify the
migration in this commit.
The migration from `CellValue` to `AssignedCell` requires several other
changes:
- `<CellValue as Var>::value()` returned `Option<F>`, whereas
`AssignedCell::<F, F>::value()` returns `Option<&F>`. This means we
need to dereference, use `Option::cloned`, or alter functions to take
`&F` arguments.
- `StateWord` in the Poseidon chip has been changed to a newtype around
`AssignedCell` (the chip was written before `CellValue` existed).
Previously, l_plus_1 was a non-binary fixed column, used to
1. provide the value of l + 1; and
2. toggle the decomposition gate.
Now, the value is copied in from the global constants column, and
the toggle is handled by a binary q_decompose selector.
- `halo2::plonk::{create_proof, verify_proof}` now take instance columns
as slices of values.
- `halo2::plonk::Permutation` has been replaced by a global permutation,
to which columns can be added with `ConstraintSystem::enable_equality`.
- The introduction of blinding rows means that various tests now require
larger circuit parameters.
Simplify the canonicity check for variable-base scalar multiplication,
by range-checking the low 130 bits rather than the low 127 bits.
Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Co-authored-by: ying tong <yingtong@z.cash>
While these two are in flux, it's hard to keep these revisions consistent
(e.g. https://github.com/zcash/zcash/pull/5217 currently depends on two
different versions of zcash_note_encryption). Using patches allows the
downstream users (i.e. zcashd) to define its own set of patches, and keep
everything in sync. This works fine now because we aren't actively making
changes to the public APIs, only additions.