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<b><a class="bz_bug_link
bz_status_NEW "
title="NEW - DFG should not insert Phantoms in bytecode parsing or as part of transformations"
href="https://bugs.webkit.org/show_bug.cgi?id=143736#c2">Comment # 2</a>
on <a class="bz_bug_link
bz_status_NEW "
title="NEW - DFG should not insert Phantoms in bytecode parsing or as part of transformations"
href="https://bugs.webkit.org/show_bug.cgi?id=143736">bug 143736</a>
from <span class="vcard"><a class="email" href="mailto:fpizlo@apple.com" title="Filip Pizlo <fpizlo@apple.com>"> <span class="fn">Filip Pizlo</span></a>
</span></b>
<pre>I think that we need to just embrace the fact that the DFG IR prior to FixupPhase *does* currently accurately represent all bytecode uses. This may be hard to maintain, but it *is* useful.
The part that we believe to be unsound is maintaining that same information in DFG IR *after* we have completed FixupPhase and are doing other transformations.
If we embrace this, then we would be able to also bring back DCE. This time it would be a pre-FixupPhase DCE.</pre>
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