fix a bug in the ReleaseDevirtualizer pass #42026
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The release-devirtualizer must not run on the same alloc_ref twice. This is a very rare case, but if it happens it's a very bad thing, because it results in a double-free crash. The fix is to detect that a dealloc_ref instruction (although it isn't "releasing"), does a memory deallocation. Found by doing some unrelated experiments.
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The release-devirtualizer must not run on the same alloc_ref twice.
This is a very rare case, but if it happens it's a very bad thing, because it results in a double-free crash.
The fix is to detect that a dealloc_ref instruction (although it isn't "releasing"), does a memory deallocation.
Found by doing some unrelated experiments.