= strlen =

== Variants ==

||= '''Name''' =||= '''Description''' =||
|| stock || MI C version ||
|| SSE2 || {{{pcmpeqb}}} and {{{pmovmskb}}} ||
|| SSE4.2 || {{{pcmpestri}}} and {{{pcpmestrm}}} ||
|| AVX || 128-bit {{{vpcmpeqb}}} and {{{vpmovmskb}}} ||
|| ERMS || {{{repne scasb}}} for machines with ERMS ||

'''Note:''' clang was too smart and optimized plain {{{strlen}}} calls away, so I had to create a copy of the C version called {{{strlen_mi()}}} to fool it.

== Machines Tested ==

||= '''CPU''' =||= '''Speed (GHz)''' =||= '''Notes''' ||
|| Xeon X5365 || 3.00 || 2 x 4 Supermicro X7DBU ||
|| Xeon X5482 || 3.20 || 2 x 4 Supermicro X7DWN+ ||
|| Xeon X5675 || 3.07 || Westmere 2 x 6 Supermicro X8DTU ||
|| Core i5-2520M || 2.50 || Sandy Bridge 1 x 4 Thinkpad X220 (4286) ||
|| Xeon E5-2680 || 2.70 || Romley 2 x 8 Supermicro X9DRW ||
|| Xeon E5-2667 v2 || 3.30 || Romley V2 2 x 8 Supermicro X9DRW ||

== Test Cases ==

||= '''Name''' =||= '''Description''' =||
|| page || aligned string one page - 1 long ||
|| short || aligned string 14 characters long ||
|| short2 || aligned string 32 characters long ||
|| short3 || aligned string 48 characters long ||
|| offset || 4 byte offset string 126 characters long ||
|| offset2 || 7 byte offset string 95 characters long ||

== Results ==

The numbers are the min value in the distribution where the values are a TSC delta across a single invocation of the test.

{{{#!th rowspan=3
'''CPU'''
}}}
{{{#!th colspan=30
'''Test / Variant'''
}}}
|--
{{{#!th colspan=5
'''page'''
}}}
{{{#!th colspan=5
'''short'''
}}}
{{{#!th colspan=5
'''short2'''
}}}
{{{#!th colspan=5
'''short3'''
}}}
{{{#!th colspan=5
'''offset'''
}}}
{{{#!th colspan=5
'''offset2'''
}}}
|--
|| '''stock''' || '''SSE2''' || '''SSSE4.2''' || '''AVX''' || '''ERMS''' || \
|| '''stock''' || '''SSE2''' || '''SSSE4.2''' || '''AVX''' || '''ERMS''' || \
|| '''stock''' || '''SSE2''' || '''SSSE4.2''' || '''AVX''' || '''ERMS''' || \
|| '''stock''' || '''SSE2''' || '''SSSE4.2''' || '''AVX''' || '''ERMS''' || \
|| '''stock''' || '''SSE2''' || '''SSSE4.2''' || '''AVX''' || '''ERMS''' || \
|| '''stock''' || '''SSE2''' || '''SSSE4.2''' || '''AVX''' || '''ERMS''' ||
|| Xeon X5365 || \
|| 1386|| '''[[span(864, style=color: green)]]'''|| -- || -- || [[span(16506, style=color:red)]]|| \
|| 81|| '''[[span(72, style=color: green)]]'''|| -- || -- || [[span(180, style=color:red)]]|| \
|| 90|| '''[[span(72, style=color: green)]]'''|| -- || -- || [[span(252, style=color:red)]]|| \
|| 90|| '''[[span(81, style=color: green)]]'''|| -- || -- || [[span(315, style=color:red)]]|| \
|| 144|| '''[[span(108, style=color: green)]]'''|| -- || -- || [[span(630, style=color:red)]]|| \
|| 135|| '''[[span(108, style=color: green)]]'''|| -- || -- || [[span(504, style=color:red)]]||
|| Xeon X5482 || \
|| 1608|| '''[[span(808, style=color: green)]]'''|| -- || -- || [[span(16464, style=color:red)]]|| \
|| 48|| '''[[span(40, style=color: green)]]'''|| -- || -- || [[span(136, style=color:red)]]|| \
|| 48|| '''[[span(40, style=color: green)]]'''|| -- || -- || [[span(140, style=color:red)]]|| \
|| 56|| '''[[span(40, style=color: green)]]'''|| -- || -- || [[span(264, style=color:red)]]|| \
|| '''80'''|| '''80'''|| -- || -- || [[span(592, style=color:red)]]|| \
|| '''72'''|| '''72'''|| -- || -- || [[span(464, style=color:red)]]||
|| Xeon X5675 || \
|| 1592|| [[span(848, style=color: green)]]|| [[span(2100, style=color:red)]]|| -- || [[span(8252, style=color:red)]]|| \
|| 60|| [[span(24, style=color: green)]]|| [[span(24, style=color: green)]]|| -- || [[span(92, style=color:red)]]|| \
|| 32|| [[span(46, style=color:red)]]|| 32|| -- || [[span(124, style=color:red)]]|| \
|| 78|| [[span(46, style=color: green)]]|| [[span(83, style=color:red)]]|| -- || [[span(156, style=color:red)]]|| \
|| 76|| [[span(64, style=color: green)]]|| [[span(104, style=color:red)]]|| -- || [[span(316, style=color:red)]]|| \
|| 64|| [[span(56, style=color: green)]]|| [[span(88, style=color:red)]]|| -- || [[span(256, style=color:red)]]||
|| Core i5-2520M || \
|| 3525|| 1950|| 6463|| 536|| 25812|| \
|| 100|| 75|| 75|| 18|| 300|| \
|| 112|| 75|| 87|| 18|| 412|| \
|| 112|| 75|| 112|| 21|| 512|| \
|| 212|| 100|| 262|| 21|| 1012|| \
|| 175|| 100|| 212|| 24|| 825 ||
|| Xeon E5-2680 || \
|| 1496|| 632|| 2048|| 644|| 8260|| \
|| 36|| 24|| 24|| 28|| 96|| \
|| 40|| 24|| 28|| 24|| 132|| \
|| 52|| 24|| 32|| 24|| 164|| \
|| 80|| 40|| 84|| 24|| 324|| \
|| 68|| 36|| 64|| 24|| 264||
|| Xeon E5-2667 v2 || \
|| 1296|| 632|| 2076|| 648|| 8260|| \
|| 24|| 24|| 24|| 24|| 100|| \
|| 36|| 24|| 28|| 24|| 132|| \
|| 48|| 24|| 28|| 28|| 164|| \
|| 80|| 44|| 84|| 24|| 324|| \
|| 64|| 28|| 64|| 24|| 264||