Commits on Oct 14, 2024

1. xts: avoid redundant bounds checks …

   Small changes to improve performance of xts by about 6%.
   
   This removes all bounds checks, which can be verified by running:
   
     go build -gcflags="-d=ssa/check_bce/debug=1" .
   
   Before this would show mutiple Found IsInBounds/IsSliceInBounds in the
   inner loops of Encrypt and Decrypt.
   
   Tweaked the benchmark to use a larger buffer to make the improvement
   more visible. XTS is often used with disk sector sizes, so larger values
   are appropriate.
   
     goos: linux
     goarch: amd64
     pkg: golang.org/x/crypto/xts
     cpu: Intel(R) Xeon(R) W-2135 CPU @ 3.70GHz
            │ before.txt  │             after.txt              │
            │   sec/op    │   sec/op     vs base               │
     XTS-12   1.720µ ± 2%   1.619µ ± 2%  -5.87% (p=0.000 n=10)
   
            │  before.txt  │              after.txt              │
            │     B/s      │     B/s       vs base               │
     XTS-12   177.4Mi ± 2%   188.5Mi ± 2%  +6.24% (p=0.000 n=10)
   
            │ before.txt │           after.txt            │
            │    B/op    │    B/op     vs base            │
     XTS-12   0.000 ± 0%   0.000 ± 0%  ~ (p=1.000 n=10) ¹
     ¹ all samples are equal
   
            │ before.txt │           after.txt            │
            │ allocs/op  │ allocs/op   vs base            │
     XTS-12   0.000 ± 0%   0.000 ± 0%  ~ (p=1.000 n=10) ¹
     ¹ all samples are equal

   

   ncruces committed Oct 14, 2024
   Configuration menu

   • View commit details
   • Copy full SHA for 6318dab
   • Browse repository at this point

   Copy the full SHA

   6318dab View commit details

   Browse the repository at this point in the history