[llvm-dev] The bit pattern after stripPointerCasts() (original) (raw)

Finkel, Hal J. via llvm-dev llvm-dev at lists.llvm.org
Thu Dec 13 19:44:12 PST 2018

On 12/13/18 9:40 PM, Matt Arsenault wrote:

On Dec 14, 2018, at 2:21 PM, Finkel, Hal J. via llvm-dev <llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.llvm.org>> wrote:

On 12/11/18 6:51 PM, Doerfert, Johannes Rudolf via llvm-dev wrote:

Hi,

in a recent review [0], Florian Hahn helped me to realize something that was rather surprising to me:

The widely popular and very useful function llvm::Value::stripPointerCasts() can return a value with a different bit pattern than the input.

Now, I think this should not be the case but I want the hear other opinions. Before I go on, please not that there is at least one location in the code base [1] that makes a wrong assumption about the bit pattern preservation.

If there's really only one place that gets this wrong (or only a few), I'm inclined to suggest option (1) below and fix this one place.

Matt, any thoughts on this?

-Hal

Yes, I’ve wanted a version which strips addrspacecast and which doesn’t before, so +1

Do you have an opinion on which should be the default?

-Hal

-Matt

-- Hal Finkel Lead, Compiler Technology and Programming Languages Leadership Computing Facility Argonne National Laboratory -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20181214/5df8aba9/attachment-0001.html>

More information about the llvm-dev mailing list