Request for reviews (S): 7041100: The load in String.equals intrinsic executed before null check (original) (raw)

Vladimir Kozlov vladimir.kozlov at oracle.com
Mon May 2 10:24:28 PDT 2011

http://cr.openjdk.java.net/~kvn/7041100/webrev

Fixed 7041100: The load in String.equals intrinsic executed before null check

String.equals intrinsic has (rec == arg) check followed by NULL check generated by gen_instanceof() when there was no NULL check before. If compiled method also has (rec == arg) check followed by explicit NULL check of argument then a load from argument could be scheduled before NULL check because of 6831314 bug.

Generate explicit check (uncast(argument) == null) in String.equals intrinsic until 6831314 is fixed. We have to uncast not-nullness otherwise the check will fold immediately and it is needed until after CCP phase.

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