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[ASAN] Initial support memory checks on scalable vector typed allocas
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Authored by reames on Mar 3 2023, 11:07 AM.

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Summary

This patch adjusts the memory instrumentation to account for scalable vector types in allocas. Note that we don't allow scalable vector globals, so we don't need to update that codepath.

A couple points.

First, this simply disables the optimization for scalable allocas. We can revisit this in the future, but it requires a bit of plumbing to get scalable object sizes through the visitor to be useful.

Second, I am simply disabling stack poisoning for scalable vector allocas. This is mostly for staging the change as I can't write a working test for memory instrumentation without doing so. I don't think it's unreasonable to do on it's own basis as without the bailout, we crash the compiler.

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reames created this revision.Mar 3 2023, 11:07 AM
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reames requested review of this revision.Mar 3 2023, 11:07 AM
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LGTM, I think don't crash the compiler is higher priority.

llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
3561

I guess we can at least assume Offset is safe when Offset >= 0 && Offset < VF, but anyway we have leave a TODO here.

This revision was not accepted when it landed; it landed in state Needs Review.Mar 15 2023, 7:59 AM
This revision was landed with ongoing or failed builds.
This revision was automatically updated to reflect the committed changes.