[Bug target/99953] In AVX, SIMD support environment, strlen performance without optimization is 3 times faster than optimized strlen function.

[novemberizing at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99953

--- Comment #7 from Hyun Sik Park <novemberizing at gmail dot com> ---
Thank you.

I was tested and the result is below.

$ ./a.out
no optimize => 0.000009640
o1 optimize => 0.000009126
o2 optimize => 0.000009422
o3 optimize => 0.000009081

experiment_optimize_3
    17d5: 48 01 c7 add %rax,%rdi
    17d8: e8 c3 f8 ff ff callq 10a0 strlen@plt
    17dd: 48 8b 74 24 08 mov 0x8(%rsp),%rsi

experiment_optimize_2
    168d: 48 01 c7 add %rax,%rdi
    1690: e8 0b fa ff ff callq 10a0 strlen@plt
    1695: 48 8b 74 24 10 mov 0x10(%rsp),%rsi

experiment_optimize_1
    154c: e8 4f fb ff ff callq 10a0 strlen@plt
    1551: 48 89 04 24 mov %rax,(%rsp)

experiment_optimize_0
    1375: 48 89 c7 mov %rax,%rdi
    1378: e8 23 fd ff ff callq 10a0 strlen@plt
    137d: 48 89 45 a8 mov %rax,-0x58(%rbp)

Thank you.