name                              old speed      new speed      delta
Encoder_EncodeAllSimple/best-8    12.2MB/s ± 1%  13.5MB/s ± 3%  +10.55%  (p=0.000 n=20+19)
Encoder_EncodeAllSimple4K/best-8  10.5MB/s ± 1%  11.9MB/s ± 1%  +13.52%  (p=0.000 n=20+19)

name                              old alloc/op   new alloc/op   delta
Encoder_EncodeAllSimple/best-8       18.0B ± 0%     16.0B ± 0%  -11.11%  (p=0.000 n=18+17)
Encoder_EncodeAllSimple4K/best-8     1.00B ± 0%     1.00B ± 0%     ~     (all equal)

As long as matchAt does not return a pointer, escape analysis determines
that the matches can stay on the stack. This works in Go 1.17, too.

name                              old speed      new speed      delta
Encoder_EncodeAllSimple/best-8    13.5MB/s ± 3%  15.3MB/s ± 2%  +13.35%  (p=0.000 n=19+19)
Encoder_EncodeAllSimple4K/best-8  11.9MB/s ± 1%  12.9MB/s ± 0%   +8.38%  (p=0.000 n=19+17)

name                              old alloc/op   new alloc/op   delta
Encoder_EncodeAllSimple/best-8       16.0B ± 0%     14.0B ± 0%  -12.50%  (p=0.000 n=17+20)
Encoder_EncodeAllSimple4K/best-8     1.00B ± 0%     1.00B ± 0%     ~     (all equal)