Re: [PATCH] small update for strlen, strnlen, use less cpu instructions

[Alexey Dobriyan]

> Now strlen() increments a variable for each character it faces,
> hence it will consume more cycles.

It doesn't matter if there is a dependency in a loop:

Before:
 520:   48 83 c0 01             add    $0x1,%rax
 524:   80 38 00                cmpb   $0x0,(%rax)
 527:   75 f7                   jne    520

After:
 500:   48 83 c0 01             add    $0x1,%rax
 504:   80 3c 07 00             cmpb   $0x0,(%rdi,%rax,1)
 508:   75 f6                   jne    500
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