Missing implementation for HLOpcodeGroup::NotHL in TranslateCBAddressUserLegacy

Repro:

Compile the following, (I used as_6_5, /Zi -enable-16bit-types /Qembed_debug )

struct LinearSHSampleData
{
       float4 linearTerms[3];
       float4 hdrColorAO;
       float4 visibilitySH;
} g_lhSampleData;

struct smallPayload
{
    LinearSHSampleData lhSampleData;
};


[numthreads(1, 1, 1)]
void main()
{
    smallPayload p;
    p.lhSampleData = g_lhSampleData;
    DispatchMesh(1, 1, 1, p);
}

I hit this line in TranslateCBAddressUserLegacy, HLOperationLower.cpp:6207:

  DXASSERT(0, "not implemented yet");

The call instruction at issue is:
CI->dump()
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %4, i8* %5, i64 80, i32 1, i1 false), !dbg !44

This assert is firing because the called function has group == HLOpcodeGroup::NotHL

Start in HLOperationLower.cpp at TranslateCBAddressUserLegacy, around line 6207, and inspect how the llvm.memcpy call is classified before the assertion. Use the provided DispatchMesh repro and its dumped call instruction as the regression case. Done means the repro no longer triggers the not-implemented assertion and the memcpy call is handled correctly.