JIT doesn't see real type of field in a shared generic type with exact context

[EgorBo]

Filed for #96773

JIT doesn't see real type of the arr field and doesn't fold the condition.

public class MyList<T>
{
    public T[] arr;
}

bool Test(MyList<string> list) => list.arr.GetType() == typeof(string[]);

Current codegen for Test:

; Method Program:Foo(MyList`1[System.String]):ubyte:this (FullOpts)
G_M55733_IG01:
G_M55733_IG02:
       mov      rax, gword ptr [rdx+0x08]
       mov      rcx, 0xD1FFAB1E      ; System.String[]
       cmp      qword ptr [rax], rcx
       sete     al
       movzx    rax, al
G_M55733_IG03:
       ret      
; Total bytes of code: 24

Expected codegen:

nullchecks
return true;

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Issue Details

---

Filed for #96773

JIT doesn't see real type of the arr field and doesn't fold the condition.

public class MyList<T>
{
    public T[] arr;
}

bool Test(MyList<string> list) => list.arr.GetType() == typeof(string[]);

Current codegen for Test:

; Method Program:Foo(MyList`1[System.String]):ubyte:this (FullOpts)
G_M55733_IG01:
G_M55733_IG02:
       mov      rax, gword ptr [rdx+0x08]
       mov      rcx, 0xD1FFAB1E      ; System.String[]
       cmp      qword ptr [rax], rcx
       sete     al
       movzx    rax, al
G_M55733_IG03:
       ret      
; Total bytes of code: 24

Expected codegen:

nullchecks
return true;

Author:	EgorBo
Assignees:	-
Labels:	area-CodeGen-coreclr, untriaged
Milestone:	-