Thanks for the pointer on running the tests. I noticed two big issues:

1. Some of the tests use shell functions like "read" that jsc doesn't provide. This is easy enough to address.

2. I was mistaken about the quality of the typed array support in JavaScriptCore. While the interpreter has knowledge of typed arrays, the actual implementation that's used when running in-browser lives in WebCore rather than in JavaScriptCore. When running in the shell only a bare minimum typed array implementation, primarily intended for JSC-only regression tests, is available. This trips up some tests since the implementation is much less complete than the one in WebCore.