diff --git a/src/coreclr/tests/issues.targets b/src/coreclr/tests/issues.targets
index 4339bda33499168da7bcbab4a7f24aafba28e458..c877455a18b7e20ca96b19b5502a76817202b13e 100644
--- a/src/coreclr/tests/issues.targets
+++ b/src/coreclr/tests/issues.targets
@@ -294,6 +294,9 @@
WindowsXamlManager and DesktopWindowXamlSource are supported for apps targeting Windows version 10.0.18226.0 and later.
+
+ 26311
+
diff --git a/src/coreclr/tests/src/JIT/Regression/JitBlue/GitHub_26311/GitHub_26311.il b/src/coreclr/tests/src/JIT/Regression/JitBlue/GitHub_26311/GitHub_26311.il
new file mode 100644
index 0000000000000000000000000000000000000000..30f20103b049e8e812805800b0edc8c5c654f522
--- /dev/null
+++ b/src/coreclr/tests/src/JIT/Regression/JitBlue/GitHub_26311/GitHub_26311.il
@@ -0,0 +1,292 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+//
+
+// The test reproduces an issue with tail call via slow helper to VSD stub over generic interface.
+
+.assembly extern System.Runtime {}
+.assembly extern System.Diagnostics.Debug {}
+.assembly extern System.Console {}
+.assembly GitHub_26311 {}
+
+
+
+.class interface private abstract auto ansi GitHub_26311.Interface`1
+{
+ .method public hidebysig newslot abstract virtual
+ instance int32 TailCallWithManyArgs(!TKey[] keys,
+ int32 index,
+ int32 length,
+ !TKey 'value',
+ object comparer) cil managed noinlining
+ {
+ } // end of method Interface`1::TailCallWithManyArgs
+
+} // end of class GitHub_26311.Interface`1
+
+.class private auto ansi beforefieldinit GitHub_26311.GenericClassOverInterface`1
+ extends [System.Runtime]System.Object
+ implements class GitHub_26311.Interface`1
+{
+ .field private static initonly class GitHub_26311.Interface`1 s_default
+ .method public hidebysig newslot virtual final
+ instance int32 TailCallWithManyArgs(!T[] 'array',
+ int32 index,
+ int32 length,
+ !T 'value',
+ object comparer) cil managed noinlining
+ {
+ // Code size 149 (0x95)
+ .maxstack 4
+ IL_0000: ldarg.1
+ IL_0001: ldnull
+ IL_0002: cgt.un
+ IL_0004: ldstr "Check the arguments in the caller to BinarySearch:"
+ + " array!"
+ IL_0009: call void [System.Diagnostics.Debug]System.Diagnostics.Debug::Assert(bool,
+ string)
+ IL_000e: ldarg.2
+ IL_000f: ldc.i4.0
+ IL_0010: clt
+ IL_0012: ldc.i4.0
+ IL_0013: ceq
+ IL_0015: ldstr "Check the arguments in the caller BinarySearch: in"
+ + "dex!"
+ IL_001a: call void [System.Diagnostics.Debug]System.Diagnostics.Debug::Assert(bool,
+ string)
+ IL_001f: ldarg.3
+ IL_0020: ldc.i4.0
+ IL_0021: clt
+ IL_0023: ldc.i4.0
+ IL_0024: ceq
+ IL_0026: ldstr "Check the arguments in the caller BinarySearch: le"
+ + "ngth!"
+ IL_002b: call void [System.Diagnostics.Debug]System.Diagnostics.Debug::Assert(bool,
+ string)
+ IL_0030: ldarg.1
+ IL_0031: ldlen
+ IL_0032: conv.i4
+ IL_0033: ldarg.2
+ IL_0034: sub
+ IL_0035: ldarg.3
+ IL_0036: bge.s IL_007d
+
+ IL_0038: ldc.i4.6
+ IL_0039: newarr [System.Runtime]System.Object
+ IL_003e: dup
+ IL_003f: ldc.i4.0
+ IL_0040: ldstr "index: "
+ IL_0045: stelem.ref
+ IL_0046: dup
+ IL_0047: ldc.i4.1
+ IL_0048: ldarg.2
+ IL_0049: box [System.Runtime]System.Int32
+ IL_004e: stelem.ref
+ IL_004f: dup
+ IL_0050: ldc.i4.2
+ IL_0051: ldstr ", length: "
+ IL_0056: stelem.ref
+ IL_0057: dup
+ IL_0058: ldc.i4.3
+ IL_0059: ldarg.3
+ IL_005a: box [System.Runtime]System.Int32
+ IL_005f: stelem.ref
+ IL_0060: dup
+ IL_0061: ldc.i4.4
+ IL_0062: ldstr ", array length: "
+ IL_0067: stelem.ref
+ IL_0068: dup
+ IL_0069: ldc.i4.5
+ IL_006a: ldarg.1
+ IL_006b: ldlen
+ IL_006c: conv.i4
+ IL_006d: box [System.Runtime]System.Int32
+ IL_0072: stelem.ref
+ IL_0073: call string [System.Runtime]System.String::Concat(object[])
+ IL_0078: call void [System.Console]System.Console::WriteLine(string)
+ IL_007d: ldarg.1
+ IL_007e: ldlen
+ IL_007f: conv.i4
+ IL_0080: ldarg.2
+ IL_0081: sub
+ IL_0082: ldarg.3
+ IL_0083: clt
+ IL_0085: ldc.i4.0
+ IL_0086: ceq
+ IL_0088: ldstr "Check the arguments in the caller BinarySearch for"
+ + " array.Length - index >= length!"
+ IL_008d: call void [System.Diagnostics.Debug]System.Diagnostics.Debug::Assert(bool,
+ string)
+ IL_0092: ldc.i4.s 100
+ IL_0094: ret
+ } // end of method GenericClassOverInterface`1::TailCallWithManyArgs
+
+ .method public hidebysig specialname static
+ class GitHub_26311.Interface`1
+ get_Default() cil managed
+ {
+ // Code size 6 (0x6)
+ .maxstack 8
+ IL_0000: ldsfld class GitHub_26311.Interface`1 class GitHub_26311.GenericClassOverInterface`1::s_default
+ IL_0005: ret
+ } // end of method GenericClassOverInterface`1::get_Default
+
+ .method private hidebysig static class GitHub_26311.Interface`1
+ CreateGenericClassOverInterface() cil managed noinlining
+ {
+ // Code size 6 (0x6)
+ .maxstack 8
+ IL_0000: newobj instance void class GitHub_26311.GenericClassOverInterface`1::.ctor()
+ IL_0005: ret
+ } // end of method GenericClassOverInterface`1::CreateGenericClassOverInterface
+
+ .method public hidebysig specialname rtspecialname
+ instance void .ctor() cil managed
+ {
+ // Code size 7 (0x7)
+ .maxstack 8
+ IL_0000: ldarg.0
+ IL_0001: call instance void [System.Runtime]System.Object::.ctor()
+ IL_0006: ret
+ } // end of method GenericClassOverInterface`1::.ctor
+
+ .method private hidebysig specialname rtspecialname static
+ void .cctor() cil managed
+ {
+ // Code size 11 (0xb)
+ .maxstack 8
+ IL_0000: call class GitHub_26311.Interface`1 class GitHub_26311.GenericClassOverInterface`1::CreateGenericClassOverInterface()
+ IL_0005: stsfld class GitHub_26311.Interface`1 class GitHub_26311.GenericClassOverInterface`1::s_default
+ IL_000a: ret
+ } // end of method GenericClassOverInterface`1::.cctor
+
+ .property class GitHub_26311.Interface`1
+ Default()
+ {
+ .get class GitHub_26311.Interface`1 GitHub_26311.GenericClassOverInterface`1::get_Default()
+ } // end of property GenericClassOverInterface`1::Default
+} // end of class GitHub_26311.GenericClassOverInterface`1
+
+.class private auto ansi beforefieldinit GitHub_26311.Program
+ extends [System.Runtime]System.Object
+{
+ .method public hidebysig static int32 Test() cil managed noinlining
+ {
+ // Code size 104 (0x68)
+ .maxstack 6
+ .locals init (int32[] V_0,
+ int32 V_1,
+ int32 V_2,
+ int32 V_3)
+ IL_0000: ldc.i4.6
+ IL_0001: newarr [System.Runtime]System.Int32
+ IL_0006: dup
+ IL_0007: ldtoken field valuetype ''/'__StaticArrayInitTypeSize=24' ''::DB17E883A647963A26D973378923EF4649801319
+ IL_000c: call void [System.Runtime]System.Runtime.CompilerServices.RuntimeHelpers::InitializeArray(class [System.Runtime]System.Array,
+ valuetype [System.Runtime]System.RuntimeFieldHandle)
+ IL_0011: stloc.0
+ IL_0012: ldc.i4.s 9
+ IL_0014: stloc.1
+ IL_0015: ldc.i4.0
+ IL_0016: stloc.2
+ IL_0017: ldc.i4.5
+ IL_0018: stloc.3
+ IL_0019: ldloc.0
+ IL_001a: brtrue.s IL_0027
+
+ IL_001c: ldstr "array == null"
+ IL_0021: newobj instance void [System.Runtime]System.Exception::.ctor(string)
+ IL_0026: throw
+
+ IL_0027: ldloc.2
+ IL_0028: ldc.i4.0
+ IL_0029: bge.s IL_0036
+
+ IL_002b: ldstr "index < 0"
+ IL_0030: newobj instance void [System.Runtime]System.Exception::.ctor(string)
+ IL_0035: throw
+
+ IL_0036: ldloc.3
+ IL_0037: ldc.i4.0
+ IL_0038: bge.s IL_0045
+
+ IL_003a: ldstr "length < 0"
+ IL_003f: newobj instance void [System.Runtime]System.Exception::.ctor(string)
+ IL_0044: throw
+
+ IL_0045: ldloc.0
+ IL_0046: ldlen
+ IL_0047: conv.i4
+ IL_0048: ldloc.2
+ IL_0049: sub
+ IL_004a: ldloc.3
+ IL_004b: bge.s IL_0058
+
+ IL_004d: ldstr "array.Length - index < length"
+ IL_0052: newobj instance void [System.Runtime]System.Exception::.ctor(string)
+ IL_0057: throw
+
+ IL_0058: call class GitHub_26311.Interface`1 class GitHub_26311.GenericClassOverInterface`1::get_Default()
+ IL_005d: ldloc.0
+ IL_005e: ldloc.2
+ IL_005f: ldloc.3
+ IL_0060: ldloc.1
+ IL_0061: ldnull
+ IL_0062: tail. // tail call to interface method over generic with many arguments.
+ IL_0063: callvirt instance int32 class GitHub_26311.Interface`1::TailCallWithManyArgs(!0[],
+ int32,
+ int32,
+ !0,
+ object)
+ IL_0067: ret
+ } // end of method Program::Test
+
+ .method private hidebysig static int32
+ Main(string[] args) cil managed
+ {
+ .entrypoint
+ // Code size 26 (0x1a)
+ .maxstack 8
+ IL_0000: call int32 GitHub_26311.Program::Test()
+ IL_0005: dup
+ IL_0006: ldc.i4.s 100
+ IL_0008: ceq
+ IL_000a: call void [System.Diagnostics.Debug]System.Diagnostics.Debug::Assert(bool)
+ IL_000f: ldstr "Passed"
+ IL_0014: call void [System.Console]System.Console::WriteLine(string)
+ IL_0019: ret
+ } // end of method Program::Main
+
+ .method public hidebysig specialname rtspecialname
+ instance void .ctor() cil managed
+ {
+ // Code size 7 (0x7)
+ .maxstack 8
+ IL_0000: ldarg.0
+ IL_0001: call instance void [System.Runtime]System.Object::.ctor()
+ IL_0006: ret
+ } // end of method Program::.ctor
+
+} // end of class GitHub_26311.Program
+
+.class private auto ansi sealed ''
+ extends [System.Runtime]System.Object
+{
+ .custom instance void [System.Runtime]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = ( 01 00 00 00 )
+ .class explicit ansi sealed nested private '__StaticArrayInitTypeSize=24'
+ extends [System.Runtime]System.ValueType
+ {
+ .pack 1
+ .size 24
+ } // end of class '__StaticArrayInitTypeSize=24'
+
+ .field static assembly initonly valuetype ''/'__StaticArrayInitTypeSize=24' DB17E883A647963A26D973378923EF4649801319 at I_00002B7C
+} // end of class ''
+
+
+// =============================================================
+
+.data cil I_00002B7C = bytearray (
+ 00 00 00 00 01 00 00 00 02 00 00 00 03 00 00 00
+ 04 00 00 00 05 00 00 00)
diff --git a/src/coreclr/tests/src/JIT/Regression/JitBlue/GitHub_26311/GitHub_26311.ilproj b/src/coreclr/tests/src/JIT/Regression/JitBlue/GitHub_26311/GitHub_26311.ilproj
new file mode 100644
index 0000000000000000000000000000000000000000..e7c67cc80e853321b1e91299296d675bddd642bf
--- /dev/null
+++ b/src/coreclr/tests/src/JIT/Regression/JitBlue/GitHub_26311/GitHub_26311.ilproj
@@ -0,0 +1,12 @@
+
+
+ Exe
+
+
+ None
+ True
+
+
+
+
+