chore: universal handling for coord constancy in cycle_group#18253
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ledwards2225 merged 3 commits intomerge-train/barretenbergfrom Nov 7, 2025
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chore: universal handling for coord constancy in cycle_group#18253ledwards2225 merged 3 commits intomerge-train/barretenbergfrom
ledwards2225 merged 3 commits intomerge-train/barretenbergfrom
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ledwards2225
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Nov 6, 2025
| _is_standard_res = predicate.get_value() ? lhs._is_standard : rhs._is_standard; | ||
| } | ||
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| // AUDITTODO: Talk to Sasha. Comment seems to be unrelated and its not clear why the logic is needed. |
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This AUDITTODO was outdated - this is exactly handling the case in question that is now solved by the constructor updates
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Nov 7, 2025
| // For the simplicity of methods in this class, we ensure that the coordinates of a point always have the same | ||
| // constancy. If they don't, we convert the non-constant coordinate to a fixed witness. | ||
| if (_x.is_constant() != _y.is_constant()) { | ||
| info("Warning: cycle_group constructed with inconsistent coordinate constancy - converting to fixed witness"); |
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I think we should remove this warning. If cycle_group does not handle mixed 'constancy', then it's his problem and it should not warn about it because it has a workaround.
This makes the blackbox interface in Noir cleaner and removes complexity by not having to take care of constant/witness inputs to the blackbox. Furthermore, 'DSL' can introduce this inconsistency by itself and getting such warning depending on the inputs looks strange.
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Removed warning message for inconsistent coordinate constancy in cycle_group.
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BEGIN_COMMIT_OVERRIDE chore: remove more pg references and leftovers (#18260) refactor: Migrate --update_inputs flag to --vk_policy option (#18237) chore: stdlib byte_array and bool external audit fixes (#17838) chore: update naming in bb_proof_verification lib (#18269) chore: cycle group 13 (#18200) chore: universal handling for coord constancy in cycle_group (#18253) END_COMMIT_OVERRIDE
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Its been noted in a few locations that use of field_t::conditional_assign with a non-constant predicate on the individual coordinates of a cycle_group element prior to construction can result in mixed constancy. E.g. if trying to conditionally assign between two points whose coordinates are constant but agree in only one or the other coordinate. In this case the coordinate that agrees will produce a constant, while the two that disagree will produce a witness. To avoid the need to handle this in disparate locations, we opt to handle it once and for all at the single interface for cycle_group. In particular, if we encounter mixed constancy, we convert the constant coordinate to a fixed witness. Closes #17514
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Its been noted in a few locations that use of field_t::conditional_assign with a non-constant predicate on the individual coordinates of a cycle_group element prior to construction can result in mixed constancy. E.g. if trying to conditionally assign between two points whose coordinates are constant but agree in only one or the other coordinate. In this case the coordinate that agrees will produce a constant, while the two that disagree will produce a witness. To avoid the need to handle this in disparate locations, we opt to handle it once and for all at the single interface for cycle_group. In particular, if we encounter mixed constancy, we convert the constant coordinate to a fixed witness.
Closes #17514