EgorBot for EgorBo in #109036

[EgorBot]

Processing https://github.com/dotnet/runtime/pull/109036#issuecomment-2423353753 command:

Command

-arm64 --envvars DOTNET_JitDisasm:Bestcase ```cs using BenchmarkDotNet.Attributes; using BenchmarkDotNet.Running; public class Bench { string s = "https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet10/"; [Benchmark] public bool Bestcase() => s.StartsWith("https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet10", StringComparison.Ordinal); [Benchmark] public bool Bestcase_IgnoreCase() => s.StartsWith("https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet10", StringComparison.OrdinalIgnoreCase); // Worst case: differs at 1st char: [Benchmark] public bool Worstcase() => s.StartsWith("xttps://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet10", StringComparison.Ordinal); [Benchmark] public bool Worstcase_IgnoreCase() => s.StartsWith("xttps://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet10", StringComparison.OrdinalIgnoreCase); } ```

(EgorBot will reply in this issue)

[EgorBot]

Benchmark results on Arm64

BenchmarkDotNet v0.14.0, Ubuntu 24.04 LTS (Noble Numbat)
Arm64
  Job-NOPWKW : .NET 10.0.0 (42.42.42.42424), Arm64 RyuJIT AdvSIMD
  Job-CAQCQB : .NET 10.0.0 (42.42.42.42424), Arm64 RyuJIT AdvSIMD
EnvironmentVariables=DOTNET_JitDisasm=Bestcase

Method	Toolchain	Mean	Error	Ratio
Bestcase	Main	4.6838 ns	0.0037 ns	1.00
Bestcase	PR	0.8703 ns	0.0018 ns	0.19
Bestcase_IgnoreCase	Main	8.6444 ns	0.0931 ns	1.00
Bestcase_IgnoreCase	PR	2.1261 ns	0.0008 ns	0.25
Worstcase	Main	0.6058 ns	0.0004 ns	1.00
Worstcase	PR	0.7916 ns	0.0012 ns	1.31
Worstcase_IgnoreCase	Main	2.5311 ns	0.0011 ns	1.00
Worstcase_IgnoreCase	PR	2.2280 ns	0.0015 ns	0.88

BDN_Artifacts.zip

[EgorBot]

cc @EgorBo (logs)