commit 170b2bfca6e6b56c3de20f939798b56635e600bf
author Damien Neil <dneil@google.com> Fri Jan 24 16:42:42 2020 -0800
committer Damien Neil <dneil@google.com> Sun Jan 26 22:23:18 2020 +0000
tree 670ce04363918959ce3d66f5c05447f730518464
parent ce8f7f63536c227ee1f914c3d51a49d26f096985

internal/impl: precompute required bit in validator

Required field validation populates a bitmask of observed required
fields. Store a uint64 containing the bit to set in the validationInfo
rather than the index of the bit. Provides a noticeable speed increase
in validation.

name                             old time/op  new time/op  delta
EmptyMessage/Wire/Unmarshal      40.2ns ± 1%  40.2ns ± 2%    ~     (p=0.860 n=35+37)
EmptyMessage/Wire/Unmarshal-12   7.13ns ± 5%  7.12ns ± 1%    ~     (p=0.112 n=37+37)
RepeatedInt32/Wire/Unmarshal     6.57µs ± 1%  6.46µs ± 1%  -1.56%  (p=0.000 n=39+35)
RepeatedInt32/Wire/Unmarshal-12  1.05µs ± 2%  1.05µs ± 2%    ~     (p=0.659 n=37+33)
Required/Wire/Unmarshal           258ns ± 1%   251ns ± 1%  -2.87%  (p=0.000 n=32+38)
Required/Wire/Unmarshal-12       44.3ns ± 2%  42.4ns ± 1%  -4.36%  (p=0.000 n=36+37)

Change-Id: Ib1cb74d3e348355a6a2f66aecf8fdc4b58cd84d4
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/216420
Reviewed-by: Joe Tsai <joetsai@google.com>