Add a dedicated Ascii.IsValid path

[MihaZupan]

Similar idea as IndexOf vs Contains.
IsValid only cares about the yes/no, so it can employ tricks like reading and or-ing together multiple vectors per iteration.

Method	Toolchain	Length	Mean	Error	Ratio
AsciiIsValid_Byte	main	1	3.235 ns	0.0070 ns	1.00
AsciiIsValid_Byte	pr-original	1	2.433 ns	0.0066 ns	0.75
AsciiIsValid_Byte	pr	1	2.221 ns	0.0072 ns	0.69
AsciiIsValid_Byte	main	7	3.152 ns	0.0062 ns	1.00
AsciiIsValid_Byte	pr-original	7	1.899 ns	0.0057 ns	0.60
AsciiIsValid_Byte	pr	7	1.754 ns	0.0061 ns	0.56
AsciiIsValid_Byte	main	8	3.168 ns	0.0064 ns	1.00
AsciiIsValid_Byte	pr-original	8	1.899 ns	0.0055 ns	0.60
AsciiIsValid_Byte	pr	8	1.862 ns	0.0012 ns	0.59
AsciiIsValid_Byte	main	16	2.470 ns	0.0041 ns	1.00
AsciiIsValid_Byte	pr-original	16	1.750 ns	0.0014 ns	0.71
AsciiIsValid_Byte	pr	16	1.851 ns	0.0011 ns	0.75
AsciiIsValid_Byte	main	32	2.947 ns	0.0059 ns	1.00
AsciiIsValid_Byte	pr-original	32	1.748 ns	0.0013 ns	0.59
AsciiIsValid_Byte	pr	32	1.851 ns	0.0012 ns	0.63
AsciiIsValid_Byte	main	64	4.340 ns	0.0067 ns	1.00
AsciiIsValid_Byte	pr-original	64	1.892 ns	0.0043 ns	0.44
AsciiIsValid_Byte	pr	64	2.179 ns	0.0013 ns	0.50
AsciiIsValid_Byte	main	128	5.044 ns	0.0398 ns	1.00
AsciiIsValid_Byte	pr-original	128	2.469 ns	0.0072 ns	0.49
AsciiIsValid_Byte	pr	128	2.444 ns	0.0065 ns	0.49
AsciiIsValid_Byte	main	256	7.108 ns	0.0190 ns	1.00
AsciiIsValid_Byte	pr-original	256	3.104 ns	0.0495 ns	0.44
AsciiIsValid_Byte	pr	256	3.315 ns	0.0526 ns	0.47
AsciiIsValid_Byte	main	1000	25.653 ns	0.0449 ns	1.00
AsciiIsValid_Byte	pr-original	1000	6.195 ns	0.0042 ns	0.24
AsciiIsValid_Byte	pr	1000	6.519 ns	0.0056 ns	0.25
AsciiIsValid_Byte	main	10000	167.230 ns	0.0811 ns	1.00
AsciiIsValid_Byte	pr-original	10000	53.478 ns	0.0281 ns	0.32
AsciiIsValid_Byte	pr	10000	54.200 ns	0.0334 ns	0.32

Method	Toolchain	Length	Mean	Error	Ratio
AsciiIsValid_Char	main	1	3.578 ns	0.0085 ns	1.00
AsciiIsValid_Char	pr-original	1	2.024 ns	0.0078 ns	0.57
AsciiIsValid_Char	pr	1	1.749 ns	0.0083 ns	0.49
AsciiIsValid_Char	main	7	3.668 ns	0.0109 ns	1.00
AsciiIsValid_Char	pr-original	7	1.659 ns	0.0052 ns	0.45
AsciiIsValid_Char	pr	7	1.962 ns	0.0077 ns	0.54
AsciiIsValid_Char	main	8	2.793 ns	0.0064 ns	1.00
AsciiIsValid_Char	pr-original	8	1.810 ns	0.0022 ns	0.65
AsciiIsValid_Char	pr	8	1.913 ns	0.0032 ns	0.68
AsciiIsValid_Char	main	16	3.418 ns	0.0023 ns	1.00
AsciiIsValid_Char	pr-original	16	1.807 ns	0.0012 ns	0.53
AsciiIsValid_Char	pr	16	1.881 ns	0.0014 ns	0.55
AsciiIsValid_Char	main	32	4.015 ns	0.0068 ns	1.00
AsciiIsValid_Char	pr-original	32	2.074 ns	0.0013 ns	0.52
AsciiIsValid_Char	pr	32	1.900 ns	0.0014 ns	0.47
AsciiIsValid_Char	main	64	4.970 ns	0.0299 ns	1.00
AsciiIsValid_Char	pr-original	64	2.344 ns	0.0033 ns	0.47
AsciiIsValid_Char	pr	64	2.400 ns	0.0110 ns	0.49
AsciiIsValid_Char	main	128	6.941 ns	0.0275 ns	1.00
AsciiIsValid_Char	pr-original	128	4.338 ns	0.0106 ns	0.63
AsciiIsValid_Char	pr	128	3.542 ns	0.0118 ns	0.51
AsciiIsValid_Char	main	256	10.511 ns	0.0302 ns	1.00
AsciiIsValid_Char	pr-original	256	5.020 ns	0.0183 ns	0.48
AsciiIsValid_Char	pr	256	5.043 ns	0.0134 ns	0.48
AsciiIsValid_Char	main	1000	36.325 ns	0.1159 ns	1.00
AsciiIsValid_Char	pr-original	1000	11.441 ns	0.0083 ns	0.32
AsciiIsValid_Char	pr	1000	12.329 ns	0.0174 ns	0.34
AsciiIsValid_Char	main	10000	279.953 ns	0.1557 ns	1.00
AsciiIsValid_Char	pr-original	10000	101.407 ns	0.0657 ns	0.36
AsciiIsValid_Char	pr	10000	100.405 ns	0.0688 ns	0.36

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Issue Details

---

Similar idea as IndexOf vs Contains.
IsValid only cares about the yes/no, so it can employ tricks like reading and or-ing together multiple vectors per iteration.

Method	Toolchain	Length	Mean	Error	Ratio
IsValid_Byte	main	1	3.234 ns	0.0271 ns	1.00
IsValid_Byte	pr	1	2.429 ns	0.0223 ns	0.75
IsValid_Byte	main	7	3.167 ns	0.0328 ns	1.00
IsValid_Byte	pr	7	1.925 ns	0.0216 ns	0.61
IsValid_Byte	main	8	3.188 ns	0.0239 ns	1.00
IsValid_Byte	pr	8	1.954 ns	0.0258 ns	0.61
IsValid_Byte	main	16	2.562 ns	0.0307 ns	1.00
IsValid_Byte	pr	16	1.811 ns	0.0205 ns	0.71
IsValid_Byte	main	32	3.405 ns	0.0329 ns	1.00
IsValid_Byte	pr	32	1.815 ns	0.0193 ns	0.53
IsValid_Byte	main	64	3.832 ns	0.0471 ns	1.00
IsValid_Byte	pr	64	1.991 ns	0.0306 ns	0.52
IsValid_Byte	main	128	4.615 ns	0.0393 ns	1.00
IsValid_Byte	pr	128	2.467 ns	0.0259 ns	0.53
IsValid_Byte	main	1000	18.710 ns	0.1963 ns	1.00
IsValid_Byte	pr	1000	6.352 ns	0.0846 ns	0.34
IsValid_Byte	main	10000	172.507 ns	1.3804 ns	1.00
IsValid_Byte	pr	10000	55.183 ns	0.4532 ns	0.32

Method	Toolchain	Length	Mean	Error	Ratio
IsValid_Char	main	1	3.617 ns	0.0286 ns	1.00
IsValid_Char	pr	1	2.052 ns	0.0243 ns	0.57
IsValid_Char	main	7	3.651 ns	0.0355 ns	1.00
IsValid_Char	pr	7	1.714 ns	0.0209 ns	0.47
IsValid_Char	main	8	2.807 ns	0.0185 ns	1.00
IsValid_Char	pr	8	1.878 ns	0.0328 ns	0.67
IsValid_Char	main	16	3.574 ns	0.0701 ns	1.00
IsValid_Char	pr	16	1.873 ns	0.0258 ns	0.52
IsValid_Char	main	32	4.090 ns	0.0333 ns	1.00
IsValid_Char	pr	32	2.152 ns	0.0288 ns	0.53
IsValid_Char	main	64	5.034 ns	0.0670 ns	1.00
IsValid_Char	pr	64	2.427 ns	0.0256 ns	0.48
IsValid_Char	main	128	6.918 ns	0.1141 ns	1.00
IsValid_Char	pr	128	4.358 ns	0.0414 ns	0.63
IsValid_Char	main	1000	36.692 ns	0.3522 ns	1.00
IsValid_Char	pr	1000	11.824 ns	0.1359 ns	0.32
IsValid_Char	main	10000	287.754 ns	2.5790 ns	1.00
IsValid_Char	pr	10000	104.102 ns	0.9829 ns	0.36

Author:	MihaZupan
Assignees:	MihaZupan
Labels:	area-System.Buffers
Milestone:	8.0.0