The ECC test chip performs various checks that assume the chip will only
be synthesized with witnesses. This assumption is broken by the chip
printer test, so we fix the assumption here.
In order to make the changeover easier to review, we redefined
`CellValue<F>` to be `AssignedCell<F, F>`. Now we remove that type and
rename throughout the codebase.
As the underlying `Region` methods now return `AssignedCell` instead of
`Cell`, we can simplify all the places where we then constructed a
`CellValue` struct.
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).
This is only used in chip::mul::Config. In a subsequent commit,
this will be configured from mul::Config instead of from
ecc::chip::Config.
This commit does not result in circuit changes.
This is only used in chip::mul::Config. In a subsequent commit,
this will be configured from mul::Config instead of from
ecc::chip::Config.
This commit does not result in circuit changes.
This is only used in chip::mul::Config. In a subsequent commit,
this will be configured from mul::Config instead of from
ecc::chip::Config.
This commit does not result in circuit changes.
We are about to extract the sub-configs from mul::Config and refactor
them. Doing so would have moved their gate definitions past the one gate
that isn't created in a sub-config. Reordering the definitions here will
make the subsequent refactor diffs simpler to review.
We only need is_identity() in tests and can implement it on the
concrete EccPoint type. This method is flagged off by #[cfg(test)].
Co-authored-by: Daira Hopwood <daira@jacaranda.org>
Previously, these two helpers were returning different outputs.
They have now been standardised to return only the full running
sum.
Note the z_0 is the original element being decomposed by the
helper.
- Placing the Poseidon `state` columns after the `partial_sbox` column
instead of before it causes them to line up with vast stretch of free
space, enabling the pad-and-add region to be layed out there.
- Using the `Region::assign_advice_from_constant` API to initialise the
Poseidon state removes fixed-column contention between that region and
fixed-base scalar multiplication, enabling it to also be layed out
within the free space.
- If https://github.com/zcash/halo2/issues/334 were implemented then
this region would disappear.
- The overflow check in variable-base scalar mul is also moved into the
columns with free space.
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.
Jack Grigg
therealyingtong
Daira Hopwood