The golden example is String.length() over static final Strings:

    static final String TEST_STRING = "Foo";

    @Benchmark
    public int string_length() {
        return TEST_STRING.length();
    }

C2 folds the underlying (byte[].length >> coder) fine, because it both trusts the final String.value/coder, and folds arraylength.
C1 trusts String.value/coder after JDK-8149813, but does not fold arraylength yet.

Sample benchmark + generated code:
 http://cr.openjdk.java.net/~shade/8150102/FoldArrayLength.java

Proof-of-concept webrev:
 http://cr.openjdk.java.net/~shade/8150102/webrev.00