Scalar implementation of strchrnul() in RISC-V assembly and changes to the
corresponding manpage.
Performance was benchmarked on a HiFive Unmatched (SiFive HF105-001) board
using: https://github.com/clausecker/strperf
os: FreeBSD
arch: riscv
│ strchrnul_baseline │ strchrnul_scalar │
│ sec/op │ sec/op vs base │
Short 680.2µ ± 5% 435.3µ ± 0% -36.01% (p=0.000 n=20)
Mid 314.7µ ± 3% 221.4µ ± 0% -29.63% (p=0.000 n=20)
Long 152.3µ ± 0% 138.5µ ± 0% -9.08% (p=0.000 n=20)
geomean 319.5µ 237.2µ -25.75%
│ strchrnul_baseline │ strchrnul_scalar │
│ MiB/s │ MiB/s vs base │
Short 183.8 ± 5% 287.2 ± 0% +56.27% (p=0.000 n=20)
Mid 397.3 ± 3% 564.6 ± 0% +42.12% (p=0.000 n=20)
Long 820.5 ± 0% 902.5 ± 0% +9.99% (p=0.000 n=20)
geomean 391.3 527.0 +34.68%