Handle float/double for RVA[cns] optimization in fgValueNumberConstLoad

[EgorBo]

Follow up for #78783 to add support for double/float.

Example:

double Test()
{
    ReadOnlySpan<double> data = new double[] { 1.0, -2.0, 3.0, 4.0 };
    return data[1];
}

this now is folded into just return -2.0;

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Issue Details

---

Example:

double Test()
{
    ReadOnlySpan<double> data = new double[] { 1.0, -2.0, 3.0, 4.0 };
    return data[1];
}

this now is folded into just return -2.0;

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

[tannergooding]

Can we recognize similar for Vector.Create(span) and convert to a VEC_CNS?

[EgorBo]

Can we recognize similar for Vector.Create(span) and convert to a VEC_CNS?

Do you mean static readonly Vector = Vector.Create ? Yeah I have a local branch with it 🙂

[EgorBo]

PTAL @dotnet/jit-contrib - simple change