elliptic-curve: add vartime BatchInvert/BatchNormalize methods#2468
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Adds the following: - `BatchInvert::batch_invert_in_place_vartime` - `BatchNormalize::batch_normalize_vartime` Both are provided methods that currently call the constant-time path, but in the future we can potentially provide default implementations that are variable-time and optimized. Since the new methods are provided, this isn't a breaking change.
tarcieri
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Adds support for variable-time batch inversions, a method for which was added in RustCrypto/traits#2468 Benchmarks showing it's ~20% faster than the constant-time version, and ammortized ~2X faster than the single element inversion when inverting two elements field element operations/invert time: [2.5369 µs 2.5453 µs 2.5557 µs] field element operations/invert_vartime time: [2.0041 µs 2.0076 µs 2.0111 µs] field element operations/batch_invert_in_place (2p) time: [2.6878 µs 2.6929 µs 2.6980 µs] field element operations/batch_invert_in_place_vartime (2p) time: [2.1331 µs 2.1379 µs 2.1426 µs]
tarcieri
added a commit
to RustCrypto/elliptic-curves
that referenced
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Jun 25, 2026
Adds support for variable-time batch inversions, a method for which was added in RustCrypto/traits#2468 Benchmarks showing it's ~20% faster than the constant-time version, and ammortized ~2X faster than the single element inversion when inverting two elements field element operations/invert time: [2.5369 µs 2.5453 µs 2.5557 µs] field element operations/invert_vartime time: [2.0041 µs 2.0076 µs 2.0111 µs] field element operations/batch_invert_in_place (2p) time: [2.6878 µs 2.6929 µs 2.6980 µs] field element operations/batch_invert_in_place_vartime (2p) time: [2.1331 µs 2.1379 µs 2.1426 µs]
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Adds the following:
BatchInvert::batch_invert_in_place_vartimeBatchNormalize::batch_normalize_vartimeBoth are provided methods that currently call the constant-time path, but in the future we can potentially provide default implementations that are variable-time and optimized.
Since the new methods are provided, this isn't a breaking change.