Help with intrinsic testing for String.indexOf()

[Gibbons, Scott]

Hi.  I wrote a stub for implementing the indexOf method and am looking for a way to thoroughly test it.  I have good tests for both positive and negative functionality that I'm pretty confident in.  What I'm looking for is a good way to write a testcase to validate that I am not accessing memory outside the range of the strings passed to the stub.

What I'd like​ to do is to allocate an isolated page of memory such that accesses outside the page would cause a SIGSEGV.  I would like to allocate the string within the page such that the last character of the string is at the end of the page, and also allocate a string at the beginning of the page.  That way I could get clear indications of reading either past the end of the string or before the beginning (I know there's a header, so the header would be allocated at the beginning).

Is there any method at all I can use within a Java testcase to effect such behavior?  I've carefully performed code inspection and am relatively confident that I'm staying within the bounds of the strings but would like HW verification that I haven't missed anything.

Ideas?


Thanks,

--Scott Gibbons

Software Development Engineer, Runtime Engineering

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