IEqualityComparer<T> is not devirtualized with PGO #116055
Description
The following code snippet is expected to devirtualize the Equals call with the help of PGO, but it currently does not.
using System.Collections.Generic;
using System.Runtime.CompilerServices;
using System.Threading;
for (int i = 0; i < 300; i++)
{
Wrapper(EqualityComparer<string>.Default, "11", "12");
Thread.Sleep(15);
}
[MethodImpl(MethodImplOptions.NoInlining)]
static bool Wrapper<T>(IEqualityComparer<T> comparer, T t1, T t2)
=> comparer.Equals(t1, t2);We don't even instrument it, as it's indirect:
------------ BB01 [0000] [000..009) (return), preds={} succs={}
***** BB01 [0000]
STMT00000 ( 0x000[E-] ... 0x008 )
[000006] DAC-G------ * STORE_LCL_VAR long V05 tmp1
[000005] --C-G------ \--* CALL help long CORINFO_HELP_RUNTIMEHANDLE_METHOD
[000003] !---------- arg0 +--* LCL_VAR long V00 TypeCtx
[000004] H------N--- arg1 \--* CNS_INT(h) long 0x7ff9a2addd28 global ptr
***** BB01 [0000]
STMT00001 ( ??? ... ??? )
[000008] DA--------- * STORE_LCL_VAR long V06 tmp2
[000007] ----------- \--* LCL_VAR long V05 tmp1
***** BB01 [0000]
STMT00002 ( ??? ... ??? )
[000011] --CXG------ * RETURN int
[000010] --CXG------ \--* CALL ind stub int
[000000] ----------- this +--* LCL_VAR ref V01 arg0
[000001] ----------- arg1 +--* LCL_VAR ref V02 arg1
[000002] ----------- arg2 +--* LCL_VAR ref V03 arg2
[000009] ----------- calli tgt \--* LCL_VAR long V06 tmp2