Use CommonPrefixLength for SetOf sort validation

[vcsjones]

Since CommonPrefixLength is optimized and vectorized, this gives a small perf bump when validating ASN.1 SetOf sorting for "large" (greater than 16 elements). For small inputs the perf change is negligible.

Note in the table below for SetOf_CorrectSort, it shows as being 1ns slower, but other runs it ends up coming out faster, but all within a ns of each other.

Method	Job	Toolchain	Mean	Error	StdDev	Ratio	Gen 0	Gen 1	Gen 2	Allocated
SetOf_Empty	Job-GLTSSG	branch	11.96 ns	0.016 ns	0.013 ns	1.00	-	-	-	-
SetOf_Empty	Job-AXNJXB	main	11.95 ns	0.003 ns	0.002 ns	1.00	-	-	-	-
SetOf_IncorrectSort	Job-GLTSSG	branch	13,903.47 ns	9.506 ns	8.427 ns	1.00	0.0458	-	-	320 B
SetOf_IncorrectSort	Job-AXNJXB	main	13,928.41 ns	10.076 ns	8.414 ns	1.00	0.0458	-	-	320 B
SetOf_LargeIncorrectSort	Job-GLTSSG	branch	13,762.73 ns	12.703 ns	11.261 ns	0.99	0.0458	-	-	320 B
SetOf_LargeIncorrectSort	Job-AXNJXB	main	13,892.17 ns	11.766 ns	10.430 ns	1.00	0.0458	-	-	320 B
SetOf_CorrectSort	Job-GLTSSG	branch	35.48 ns	0.033 ns	0.027 ns	1.12	-	-	-	-
SetOf_CorrectSort	Job-AXNJXB	main	34.48 ns	0.040 ns	0.038 ns	1.00	-	-	-	-
SetOf_LargeCorrectSort	Job-GLTSSG	branch	43.50 ns	0.137 ns	0.128 ns	0.82	-	-	-	-
SetOf_LargeCorrectSort	Job-AXNJXB	main	53.04 ns	0.046 ns	0.043 ns	1.00	-	-	-	-

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Issue Details

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Since CommonPrefixLength is optimized and vectorized, this gives a small perf bump when validating ASN.1 SetOf sorting for "large" (greater than 16 elements). For small inputs the perf change is negligible.

Note in the table below for SetOf_CorrectSort, it shows as being 1ns slower, but other runs it ends up coming out faster, but all within a ns of each other.

Method	Job	Toolchain	Mean	Error	StdDev	Ratio	Gen 0	Gen 1	Gen 2	Allocated
SetOf_Empty	Job-GLTSSG	branch	11.96 ns	0.016 ns	0.013 ns	1.00	-	-	-	-
SetOf_Empty	Job-AXNJXB	main	11.95 ns	0.003 ns	0.002 ns	1.00	-	-	-	-
SetOf_IncorrectSort	Job-GLTSSG	branch	13,903.47 ns	9.506 ns	8.427 ns	1.00	0.0458	-	-	320 B
SetOf_IncorrectSort	Job-AXNJXB	main	13,928.41 ns	10.076 ns	8.414 ns	1.00	0.0458	-	-	320 B
SetOf_LargeIncorrectSort	Job-GLTSSG	branch	13,762.73 ns	12.703 ns	11.261 ns	0.99	0.0458	-	-	320 B
SetOf_LargeIncorrectSort	Job-AXNJXB	main	13,892.17 ns	11.766 ns	10.430 ns	1.00	0.0458	-	-	320 B
SetOf_CorrectSort	Job-GLTSSG	branch	35.48 ns	0.033 ns	0.027 ns	1.12	-	-	-	-
SetOf_CorrectSort	Job-AXNJXB	main	34.48 ns	0.040 ns	0.038 ns	1.00	-	-	-	-
SetOf_LargeCorrectSort	Job-GLTSSG	branch	43.50 ns	0.137 ns	0.128 ns	0.82	-	-	-	-
SetOf_LargeCorrectSort	Job-AXNJXB	main	53.04 ns	0.046 ns	0.043 ns	1.00	-	-	-	-

Author:	vcsjones
Assignees:	-
Labels:	area-System.Formats.Asn1
Milestone:	-