[PATCH] D103867: [CHR] Don't run ControlHeightReduction if any BB has address taken

[Xun Li via Phabricator via llvm-commits]

lxfind added a comment.

> Poking around it looks like this should be handled for inlining, not sure why the previous case we ran into wasn't covered by that code below from `CallAnalyzer::analyze()`
>
>   // Disallow inlining a blockaddress with uses other than strictly callbr.
>   // A blockaddress only has defined behavior for an indirect branch in the
>   // same function, and we do not currently support inlining indirect
>   // branches.  But, the inliner may not see an indirect branch that ends up
>   // being dead code at a particular call site. If the blockaddress escapes
>   // the function, e.g., via a global variable, inlining may lead to an
>   // invalid cross-function reference.
>   // FIXME: pr/39560: continue relaxing this overt restriction.
>   if (BB->hasAddressTaken())
>     for (User *U : BlockAddress::get(&*BB)->users())
>       if (!isa<CallBrInst>(*U))
>         return InlineResult::failure("blockaddress used outside of callbr");
>
>> LGTM, thanks for the fix.

I think because that code is only checking for CallBrInst users. But in a computed goto pattern, the addresses are usually just stored in a global variable.


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  https://reviews.llvm.org/D103867/new/

https://reviews.llvm.org/D103867