• fpizlo@apple.com's avatar
    DFG::SpeculativeJIT::isKnownXYZ methods should use CFA rather than other things · ba5ebb20
    fpizlo@apple.com authored
    Reviewed by Geoffrey Garen.
    These methods were previously using GenerationInfo and other things to try to
    gain information that the CFA could give away for free, if you asked kindly
    Also fixed CallLinkStatus's dump() method since it was making an invalid
    assertion: we most certainly can have a status where the structure is non-null
    and the executable is null, like if we're dealing with an InternalFunction.
    Also removed calls to isKnownNotXYZ from fillSpeculateABC methods in 32_64. I
    don't know why that was there. But it was causing asserts if the value was
    empty - i.e. we had already exited unconditionally but we didn't know it. I
    could have fixed this by introducing another form of isKnownNotXYZ which was
    tolerant of empty values, but I didn't feel like fixing code that I knew to be
    unnecessary. (More deeply, isKnownNotCell, for example, really asks: "do you
    know that this value can never be a cell?" while some of the previous uses
    wanted to ask: "do you know that this is a value that is not a cell?". The
    former is "true" if the value is a contradiction [i.e. BOTTOM], while the
    latter is "false" for contradictions, since contradictions are not values.)
    * bytecode/CallLinkStatus.cpp:
    * bytecode/CallLinkStatus.h:
    * dfg/DFGSpeculativeJIT.cpp:
    * dfg/DFGSpeculativeJIT.h:
    * dfg/DFGSpeculativeJIT32_64.cpp:
    * dfg/DFGStructureAbstractValue.h:
    git-svn-id: http://svn.webkit.org/repository/webkit/trunk@143242 268f45cc-cd09-0410-ab3c-d52691b4dbfc