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  1. JDK
  2. JDK-8200238

Reduce number of exceptions created when calling MemberName$Factory::resolveOrNull

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    • Icon: Enhancement Enhancement
    • Resolution: Fixed
    • Icon: P4 P4
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    • core-libs

      MethodHandleNatives::resolve are used by both MemberName$Factory::resolveOrFail and ::resolveOrNull, the latter allowing speculative lookup of methods.

      While the linkResolver code in the VM will create and throw exceptions for all cases where a method or field is missing, these are caught by MethodHandles::resolve_MemberName and an empty handle is returned instead. However, the outer method, MHN_resolve_Mem will always create a new exception and throw it.

      In case of resolveOrNull, we'll then ignore whatever exception is thrown in the java code, so in effect we're creating and ignoring two exceptions on a failed lookup.

      We can cut this in half by passing a boolean to MethodHandleNatives::resolve to indicate whether we're doing a speculative lookup (resolveOrNull) or not (resolveOrFail).

      This is related to JDK-8161588, which entertained the idea that we could make the expected cases of a speculative lookup not throw any exceptions at all.

            redestad Claes Redestad
            redestad Claes Redestad
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