Reserve fast dictionary slots for Tier1 code

[jkotas]

Disable use of fast dictionary slots for R2R images when tiered JITing is enabled.

Fixes #22400

[jkotas]

cc @kouvel @AndyAyersMS @fadimounir

[stephentoub]

Thanks, Jan.

Fixes #22400

There were several outcomes there from Andy's investigation. Do we have issues for the remaining ones, e.g. making the number of dictionary slots for generic methods dynamic?

[jkotas]

making the number of dictionary slots for generic methods dynamic?

Opened https://github.com/dotnet/coreclr/issues/22624

[jkotas]

System.Net.NetworkInformation.Tests.PingTest.SendPingAsyncWithIPAddress(addressFamily: InterNetwork) [FAIL]
  System.Net.NetworkInformation.PingException : An exception occurred during a Ping request.
  ---- System.ComponentModel.Win32Exception : The operation completed successfully.
  Stack Trace:
     D:\j\workspace\windows-TGrou---74aa877a\src\System.Net.Ping\tests\FunctionalTests\PingTest.cs(749,0): at System.Net.NetworkInformation.Tests.PingTest.SendPingAsync(Func`2 sendPing, Action`1 pingResultValidator)
     D:\j\workspace\windows-TGrou---74aa877a\src\System.Net.Ping\tests\FunctionalTests\PingTest.cs(131,0): at System.Net.NetworkInformation.Tests.PingTest.SendPingAsyncWithIPAddress(AddressFamily addressFamily)
     --- End of stack trace from previous location where exception was thrown ---
     ----- Inner Stack Trace -----
     F:\vsagent\13\s\src\System.Net.Ping\src\System\Net\NetworkInformation\Ping.Windows.cs(96,0): at System.Net.NetworkInformation.Ping.DoSendPingCore(IPAddress address, Byte[] buffer, Int32 timeout, PingOptions options, Boolean isAsync)
     F:\vsagent\13\s\src\System.Net.Ping\src\System\Net\NetworkInformation\Ping.Windows.cs(42,0): at System.Net.NetworkInformation.Ping.SendPingAsyncCore(IPAddress address, Byte[] buffer, Int32 timeout, PingOptions options)
     F:\vsagent\13\s\src\System.Net.Ping\src\System\Net\NetworkInformation\Ping.cs(331,0): at System.Net.NetworkInformation.Ping.SendPingAsync(IPAddress address, Int32 timeout, Byte[] buffer, PingOptions options)

[jkotas]

Opened https://github.com/dotnet/corefx/issues/35351 on the CoreFX failure

[AndyAyersMS]

Test case over in #22400 now shows:

Prejitted ?	Tiered ?	Time (ms)	Notes
No	No	1034
No	Yes	1091	small bit of tiering overhead
Yes	No	2032	large bit of R2R overhead
Yes	Yes	1543 1106	R2R no longer using fast slots

[sergiy-k]

@AndyAyersMS, the first three rows show exactly the same Time as you shown in https://github.com/dotnet/coreclr/issues/22400. Is it because this change had no effect on those configurations or you just did not re-ran them? I'm in particular interested in row 3.

[AndyAyersMS]

Jan's change only impacted the last row.

Row 3 is slower than the others because the R2R jit-generated code doesn't check for the fast slot case inline -- it always calls the helper.

[sergiy-k]

Thank you!